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Sample records for activating factor baff

  1. Molecular cloning, expression and bioactivity of B cell activating factor (BAFF) in African ostrich.

    PubMed

    Yang, Keli; Xiao, Ke; Huang, Haibo; Lu, Shun; Zhong, Juming; Ansari, Abdur Rahman; Khaliq, Haseeb; Song, Hui; Liu, Huazhen; Peng, Kemei

    2015-09-01

    B cell activating factor (BAFF), which belongs to the tumor necrosis factor (TNF) family, is testified to play a critical role in B cell survival, proliferation, maturation and immunoglobulin secretion. In the present study, the cDNA of open reading frame (ORF) in African ostrich (Struthio camelus) BAFF (designated OsBAFF) was cloned by reverse transcription-PCR (RT-PCR). The OsBAFF gene encodes a 288-amino acid protein containing a predicted transmembrane domain and a putative furin protease cleavage site like BAFFs from chicken (cBAFF), quail (qBAFF), duck (dBAFF), goose (gBAFF) and dove (doBAFF). RT-PCR analysis showed that the OsBAFF gene is strongly expressed in the bursa of Fabricius, thymus, spleen, and bone marrow. The soluble OsBAFF had been cloned into pET28a. SDS-PAGE and Western blotting analysis confirmed that the soluble fusion protein His-OsBAFF was efficiently expressed in Escherichia coli Rosset (DE3). In vitro, purified OsBAFF was not only able to promote the survival of African ostrich bursal lymphocytes, but also able to co-stimulate proliferation of mouse splenic B cells. The expression of OsBAFF in lymphocyte cells was higher than the control after LPS stimulation. These findings indicated that OsBAFF plays an important role in survival and proliferation of African ostrich bursal lymphocytes, which may provide valuable information for research into the immune system of African ostrich and OsBAFF may serve as a potential immunologic factor for enhancing immunological efficacy in African ostrich and any other birds.

  2. Characterisation and expression analysis of B-cell activating factor (BAFF) in spiny dogfish (Squalus acanthias): cartilaginous fish BAFF has a unique extra exon that may impact receptor binding.

    PubMed

    Li, Ronggai; Dooley, Helen; Wang, Tiehui; Secombes, Christopher J; Bird, Steve

    2012-04-01

    B-cell activating factor (BAFF), also known as tumour necrosis factor (TNF) ligand superfamily member 13B, is an important immune regulator with critical roles in B-cell survival, proliferation, differentiation and immunoglobulin secretion. A BAFF gene has been cloned from spiny dogfish (Squalus acanthias) and its expression studied. The dogfish BAFF encodes for an anchored type-II transmembrane protein of 288 aa with a putative furin protease cleavage site and TNF family signature as seen in BAFFs from other species. The identity of dogfish BAFF has also been confirmed by conserved cysteine residues, and phylogenetic tree analysis. The dogfish BAFF gene has an extra exon not seen in teleost fish, birds and mammals that encodes for 29 aa and may impact on receptor binding. The dogfish BAFF is highly expressed in immune tissues, such as spleen, and is up-regulated by PWM in peripheral blood leucocytes, suggesting a potentially important role in the immune system.

  3. CsBAFF, a Teleost B Cell Activating Factor, Promotes Pathogen-Induced Innate Immunity and Vaccine-Induced Adaptive Immunity

    PubMed Central

    Sun, Yun; Sun, Li

    2015-01-01

    B cell activating factor (BAFF) is a member of the tumor necrosis factor family that is known to play an important role in B cell activation, proliferation, and differentiation in mammals. However, studies of BAFF in teleosts are very limited and its function, in particular that under in vivo conditions, is essentially unknown. In this study, we conducted in vivo as well as in vitro functional analyses of a BAFF homologue (CsBAFF) from the teleost fish tongue sole (Cynoglossus semilaevis). CsBAFF is composed of 261 residues and shares moderate sequence identities with known BAFFs of other teleosts. CsBAFF expression was most abundant in immune organs and was upregulated during bacterial infection. Purified recombinant CsBAFF (rCsBAFF) bound to tongue sole lymphocytes and promoted cellular proliferation and survival. The results of an in vivo study showed that CsBAFF overexpression in tongue sole significantly enhanced macrophage activation and reduced bacterial infection in fish tissues, whereas knockdown of CsBAFF expression resulted in increased bacterial dissemination and colonization in fish tissues. Furthermore, vaccination studies showed that CsBAFF enhanced the immunoprotection of a DNA vaccine and augmented the production of specific serum antibodies. Taken together, these results provide the first in vivo evidence to indicate that teleost BAFF is an immunostimulator that significantly contributes to the innate antibacterial immune response and vaccine-induced adaptive immune response. PMID:26295165

  4. B cell activating factor (BAFF) selects IL-10(-)B cells over IL-10(+)B cells during inflammatory responses.

    PubMed

    Ma, Ning; Zhang, Yu; Liu, Qilin; Wang, Zhiding; Liu, Xiaoling; Zhu, Gaizhi; Yu, Dandan; Han, Gencheng; Chen, Guojiang; Hou, Chunmei; Wang, Tianxiao; Ma, Yuanfang; Shen, Beifen; Li, Yan; Xiao, He; Wang, Renxi

    2017-05-01

    B cell activating factor (BAFF) regulates B cell maturation, survival, function, and plays a critical pathogenic role in autoimmune diseases. It remains unclear how BAFF affects IL-10(-)B cells versus regulatory B cells (Bregs) in inflammatory responses. In this study, we found that IL-10-expressing Bregs decreased in lupus-prone MRL/lpr mice and experimental allergic encephalomyelitis (EAE) mice. On blockade of the effects of BAFF with TACI-IgG, IL-10(+) Bregs were upregulated in MRL/lpr and EAE mice. In addition, BAFF expanded IL-10(+)B cells over IL-10(-)B cells under noninflammatory conditions in vitro, whereas it expanded IL-10(-)B cells over IL-10(+)B cells during inflammatory responses, such as stimulation with autoantigen and LPS. Finally, the selection of IL-10(-)B cells over IL-10(+)B cells by BAFF was dependent on BAFF receptors (BAFFR, TACI, and BCMA) that were upregulated by inflammatory responses. This study suggests that BAFF selects IL-10(-)B cells over IL-10(+) regulatory B cells via BAFF receptors in inflammatory responses.

  5. Changes in Blood B Cell-Activating Factor (BAFF) Levels in Multiple Sclerosis: A Sign of Treatment Outcome

    PubMed Central

    Kannel, Karin; Alnek, Kristi; Vahter, Liina; Gross-Paju, Katrin; Uibo, Raivo; Kisand, Kalle V.

    2015-01-01

    Multiple sclerosis (MS) is mediated primarily by autoreactive T cells. However, evidence suggesting the involvement of humoral immunity in brain diseases has increased interest in the role of B cells and their products during MS pathogenesis. The major survival factor for B cells, BAFF has been shown to play a role in several autoimmune conditions. Elevated BAFF levels have been reported in MS animal model and during MS relapse in patients. Moreover, disease-modifying treatments (DMT) reportedly influence blood BAFF levels in MS patients, but the significance of these changes remains unclear. The present study addresses how blood BAFF levels are associated with the clinical course of relapsing-remitting MS and the effectiveness of DMT and short-term steroid treatment. During a prospective longitudinal follow-up of 2.3 years, BAFF was measured in the blood of 170 MS patients in the stable phase and within 186 relapses. BAFF levels were significantly higher in MS patients compared to healthy controls. However, stable MS patients without relapses exhibited significantly higher BAFF levels than relapsing patients. Treatment with interferon-β and immunosuppressants raised BAFF blood levels. Interestingly, a similar effect was not seen in patients treated with glatiramer acetate. Short-term treatment with high doses of intravenous methylprednisolone did not significantly alter plasma BAFF levels in 65% of relapsing-remitting MS patients. BAFF were correlated weakly but significantly with monocyte and basophil counts, but not with other blood cell types (neutrophils, lymphocytes, or eosinophils) or inflammatory biomarkers. To our knowledge, this is the first report demonstrating that higher blood BAFF levels may reflect a more stable and effective MS treatment outcome. These results challenge hypotheses suggesting that elevated blood BAFF levels are associated with more severe disease presentation and could explain the recent failure of pharmaceutical trials targeting

  6. Elevated B-cell activating factor BAFF, but not APRIL, correlates with CSF cerebellar autoantibodies in pediatric opsoclonus-myoclonus syndrome.

    PubMed

    Fühlhuber, V; Bick, S; Kirsten, A; Hahn, A; Gerriets, T; Tschernatsch, M; Kaps, M; Preissner, K T; Blaes, F; Altenkämper, S

    2009-05-29

    Childhood opsoclonus-myoclonus syndrome (OMS) occurs idiopathic or, in association with a neuroblastoma, as a paraneoplastic syndrome. Since autoantibodies were identified in some patients, an autoimmune pathogenesis has been suspected. While the newly discovered B-cell activating factors BAFF and APRIL are involved in systemic autoimmune diseases, their association with neuroimmunological diseases is hardly understood. We here investigated the BAFF and APRIL levels in serum and cerebrospinal fluid (CSF) of OMS patients and their correlation with surface-binding autoantibodies. BAFF and APRIL were both determined by ELISA, and autoantibodies to cerebellar granular neurons (CGN) have been investigated by flow cytometry in 17 OMS patients, 16 neuroblastoma (NB) patients, 13 controls and 11 children with inflammatory neurological diseases (IND). BAFF, but no APRIL, was elevated in the CSF of OMS children and IND children. However, in contrast to IND patients, OMS patients did not have a blood-brain-barrier disturbance, indicating that BAFF was produced intrathecally in OMS patients, but not in IND patients. CSF BAFF levels showed a correlation with CSF CGN autoantibodies (r(2)=0.58, p<0.05). These data indicate that an activated B-cell system in the cerebrospinal fluid is involved in the pathogenesis of OMS, and BAFF may be a candidate parameter for the activation of B-cell immune system.

  7. Chicoric acid suppresses BAFF expression in B lymphocytes by inhibiting NF-κB activity.

    PubMed

    Chen, Lingxi; Huang, Gang; Gao, Min; Shen, Xiaodong; Gong, Wei; Xu, Zhizhen; Zeng, Yijun; He, Fengtian

    2017-03-01

    B cell activating factor belonging to the TNF family (BAFF) plays a critical role in the pathogenesis of autoimmune diseases. The inhibition of BAFF expression is an emerging therapeutic approach for these disorders. Chicoric acid (CA), a bioactive phytochemical found in several widely used traditional medicinal plants, has significant anti-inflammatory activity and anti-arthritic effects. However, the role of CA in modulation of BAFF expression remains unknown. In this study, we demonstrated that CA reduced BAFF expression in human B lymphocyte cell lines and decreased the DNA-binding activity of nuclear factor-κB (NF-κB) in the BAFF promoter region. Furthermore, CA inhibited both the nuclear translocation of p65 (the subunit of NF-κB) and the phosphorylation of IκBα (inhibitor of NF-κB). These results suggest that CA suppresses BAFF expression by inhibiting NF-κB activity, and CA may serve as a novel therapeutic agent to down-regulate excessive BAFF expression in autoimmune diseases.

  8. Serum 25-Hydroxyvitamin D3 and BAFF Levels Are Associated with Disease Activity in Primary Sjogren's Syndrome

    PubMed Central

    Lee, Sang Jin; Oh, Hye Jin; Choi, Byoong Yong; Jang, Yu Jin; Lee, Joo Youn; Park, Jin Kyun

    2016-01-01

    The study investigated the association between disease activity and serum 25-hydroxyvitamin D3 (25(OH)-D3), B cell activation of the tumor necrosis factor family (BAFF), or β2 microglobulin in patients with primary Sjogren's syndrome (SS). Sixty-nine primary SS patients and 22 sicca control patients were included in the study. Disease activity was measured with EULAR Sjogren's syndrome disease activity index (ESSDAI). Serum levels of 25(OH)-D3 and β2 microglobulin were measured by radioimmunoassay and BAFF was measured by an enzyme-linked immunosorbent assay. Serum levels of 25(OH)-D3 were significantly lower in SS patients compared to the sicca controls (p = 0.036). Serum levels of BAFF tended to be higher (p = 0.225) and those of β2 microglobulin were significantly higher in patients with SS than in sicca controls (p = 0.023). In univariate regression analyses, ESSDAI was significantly associated with serum levels of 25(OH)-D3, BAFF, and β2 microglobulin. After stepwise backward multivariate linear regression analyses including age and acute phase reactants, ESSDAI was associated with 25(OH)-D3 (β = −0.042, p = 0.015) and BAFF (β = 0.001, p = 0.015) in SS patients. In SS patients, ESSDAI is negatively associated with serum levels of 25(OH)-D3 and positively associated with BAFF. PMID:28074193

  9. Molecular and functional characterization of BAFF from the Yangtze alligator (Alligator sinensis, Alligatoridae).

    PubMed

    Zhang, Jia-Xin; Song, Ren; Sang, Ming; Sun, Si-Qing; Ma, Lei; Zhang, Jie; Zhang, Shuang-Quan

    2015-10-01

    B-cell activating factor (BAFF) from the TNF family is critical for B-cell survival and maturation. In this study, we identified a Yangtze alligator (Alligator sinensis, Alligatoridae) BAFF cDNA, designated as asBAFF, using reverse transcription polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE). The open reading frame of this cDNA encodes a 287-amino acid protein containing a predicted transmembrane domain and a furin protease cleavage site, similar to mammalian and avian BAFF. The amino acid identity between biologically soluble asBAFF (assBAFF) and csBAFF, hsBAFF, and msBAFF is 94, 76, and 71%, respectively. Real-time quantitative PCR analysis showed that the asBAFF gene is strongly expressed in the spleen. Since BAFF is always expressed as inclusion bodies in bacteria, it is difficult to purify. To enhance the soluble expression of assBAFF in Escherichia coli, we fused the extracellular region of the asBAFF gene to a small ubiquitin-related modifier gene (SUMO). Purified assBAFF was able to promote the survival of splenic lymphocytes and co-stimulate the proliferation of mouse B cells with anti-mouse IgM. These findings suggest that asBAFF plays an important role in the survival and proliferation of Yangtze alligator B cells, and because it is evolutionarily highly conserved, functional cross-reactivity exists between mammalian and Yangtze alligator BAFF.

  10. IVIG regulates BAFF expression in patients with chronic inflammatory demyelinating polyneuropathy (CIDP).

    PubMed

    Ritter, Christian; Förster, Dominik; Albrecht, Philipp; Hartung, Hans-Peter; Kieseier, Bernd C; Lehmann, Helmar C

    2014-09-15

    Recent studies indicate that the cytokine B-cell activating factor (BAFF) is involved in the pathogenesis of chronic inflammatory demyelinating polyneuropathy (CIDP). Intravenous immunoglobulin (IVIg) is standard treatment for CIDP and is known to rapidly modulate increased serum levels of pro-inflammatory cytokines. We evaluated the expression profile of BAFF and its corresponding BAFF-receptor in samples from CIDP patients, focusing on rapid changes before and after IVIg treatment. In CIDP patients BAFF serum concentrations were elevated compared to controls. Treatment with high-dose IVIg restored those elevated BAFF serum levels. Whereas treatment with IVIg did not affect BAFF production in monocytes, antibodies against BAFF could be detected in IVIg preparations, which may explain the short-term decrease of BAFF levels after IVIg treatment. Our data suggest that BAFF plays an important role in the pathogenesis of CIDP and may serve as marker for IVIg treatment response.

  11. BAFF: a local and systemic target in autoimmune diseases

    PubMed Central

    Moisini, I; Davidson, A

    2009-01-01

    BAFF (B lymphocyte activating factor of the tumour necrosis factor family) is a vital homeostatic cytokine for B cells that helps regulate both innate and adaptive immune responses. Increased serum levels of BAFF are found in a number of different autoimmune diseases, and BAFF is found in inflammatory sites in which there is lymphoid neogenesis. BAFF antagonism has been used in several autoimmune disease models, resulting in B cell depletion, decreased activation of T cells and dendritic cells (DC) and a reduction in the overall inflammatory burden. BAFF, through its interaction with BAFF-R, is required for survival of late transitional, marginal zone and mature naive B cells, all of which are depleted by BAFF blockade. Through their interactions with TACI (transmembrane activator and calcium modulator and cyclophilin ligand interactor) and BCMA (B cell maturation protein), BAFF and its homologue APRIL (a proliferation-inducing ligand), support the survival of at least some subsets of plasma cells; blockade of both cytokines results in a decrease in serum levels of immunoglobulin (Ig)G. In contrast, neither BAFF nor APRIL is required for the survival or reactivation of memory B cells or B1 cells. BAFF also helps DC maturation and interleukin (IL)-6 release and is required for proper formation of a follicular dendritic cell (FDC) network within germinal centres, although not for B cell affinity maturation. The clinical efficacy of BAFF blockade in animal models of autoimmunity may be caused both by the decline in the number of inflammatory cells and by the inhibition of DC maturation within target organs. Blockade of BAFF and its homologue APRIL are being explored for human use; several Phase I and II clinical trials of BAFF inhibitors for autoimmunity have been completed and Phase III trials are in progress. PMID:19737141

  12. Generation and characterization of tabalumab, a human monoclonal antibody that neutralizes both soluble and membrane-bound B-cell activating factor

    PubMed Central

    Manetta, Joseph; Bina, Holly; Ryan, Paul; Fox, Niles; Witcher, Derrick R; Kikly, Kristine

    2014-01-01

    B-cell activating factor (BAFF) is a B-cell survival factor with a key role in B-cell homeostasis and tolerance. Dysregulated BAFF expression may contribute to autoimmune diseases or B-cell malignancies via effects on abnormal B-lymphocyte activation, proliferation, survival, and immunoglobulin secretion. Monoclonal antibodies were generated against human BAFF, characterized for species specificity and affinity, and screened for the ability to neutralize both membrane-bound and soluble BAFF. In addition, studies were undertaken to determine the relative potency of membrane-bound and soluble BAFF. Tabalumab has a high affinity for human, cynomolgus monkey, and rabbit BAFF. No binding to mouse BAFF was detected. Tabalumab was able to neutralize soluble human, cynomolgus monkey, or rabbit BAFF with equal potency. Our data demonstrate that membrane-bound BAFF can be a more potent stimulus for B-cells than soluble BAFF, and tabalumab also neutralized membrane-bound BAFF. Tabalumab prevented BAFF from binding to BAFF receptors and demonstrated pharmacodynamic effects in human BAFF transgenic mice. Tabalumab is a high-affinity human antibody with neutralizing activity against membrane-bound and soluble BAFF. Given our findings that membrane-bound BAFF can have greater in vitro potency than soluble BAFF, neutralization of both forms of BAFF is likely to be important for optimal therapeutic effect. PMID:25258549

  13. The role of B cell-activating factor in autoimmune myasthenia gravis.

    PubMed

    Lisak, Robert P; Ragheb, Samia

    2012-12-01

    B cell-activating factor (BAFF) is important in the development and maturation of B cells and their progeny-plasma blasts and plasma cells. There is increasing evidence that BAFF is involved in the pathogenesis of several autoimmune diseases including myasthenia gravis. Increased expression of BAFF and receptors for BAFF have been demonstrated in thymus of patients with myasthenia gravis, and an increase in serum levels of BAFF have been reported in patients with myasthenia gravis. While the exact role of BAFF in the pathogenesis of myasthenia gravis is not clear, BAFF and its receptors may provide potential targets for therapy in patients with myasthenia gravis.

  14. A BAFF-R mutation associated with non-Hodgkin lymphoma alters TRAF recruitment and reveals new insights into BAFF-R signaling.

    PubMed

    Hildebrand, Joanne M; Luo, Zhenghua; Manske, Michelle K; Price-Troska, Tammy; Ziesmer, Steven C; Lin, Wai; Hostager, Bruce S; Slager, Susan L; Witzig, Thomas E; Ansell, Stephen M; Cerhan, James R; Bishop, Gail A; Novak, Anne J

    2010-11-22

    The cytokine B cell activating factor (BAFF) and its receptor, BAFF receptor (BAFF-R), modulate signaling cascades critical for B cell development and survival. We identified a novel mutation in TNFRSF13C, the gene encoding human BAFF-R, that is present in both tumor and germline tissue from a subset of patients with non-Hodgkin lymphoma. This mutation encodes a His159Tyr substitution in the cytoplasmic tail of BAFF-R adjacent to the TRAF3 binding motif. Signaling through this mutant BAFF-R results in increased NF-κB1 and NF-κB2 activity and increased immunoglobulin production compared with the wild-type (WT) BAFF-R. This correlates with increased TRAF2, TRAF3, and TRAF6 recruitment to His159Tyr BAFF-R. In addition, we document a requirement for TRAF6 in WT BAFF-R signaling. Together, these data identify a novel lymphoma-associated mutation in human BAFF-R that results in NF-κB activation and reveals TRAF6 as a necessary component of normal BAFF-R signaling.

  15. Prevalence of interferon type I signature in CD14 monocytes of patients with Sjögren's syndrome and association with disease activity and BAFF gene expression

    PubMed Central

    Brkic, Zana; Maria, Naomi I; van Helden-Meeuwsen, Cornelia G; van de Merwe, Joop P; van Daele, Paul L; Dalm, Virgil A; Wildenberg, Manon E; Beumer, Wouter; Drexhage, Hemmo A; Versnel, Marjan A

    2013-01-01

    Objective To determine the prevalence of upregulation of interferon (IFN) type I inducible genes, the so called ‘IFN type I signature’, in CD14 monocytes in 69 patients with primary Sjögren's syndrome (pSS) and 44 healthy controls (HC) and correlate it with disease manifestations and expression of B cell activating factor (BAFF). Methods Expression of IFI44L, IFI44, IFIT3, LY6E and MX1 was measured using real time quantitative PCR in monocytes. Expression values were used to calculate IFN type I scores for each subject. pSS patients positive for the IFN type I signature (IFN score≥10) and patients negative for the signature (IFN score<10) were then compared for clinical disease manifestations and BAFF expression. A bioassay using a monocytic cell line was performed to study whether BAFF mRNA expression was inducible by IFN type I activity in serum of patients with pSS. Results An IFN type I signature was present in 55% of patients with pSS compared with 4.5% of HC. Patients with the IFN type I signature showed: (a) higher EULAR Sjögren's Syndrome Disease Activity Index scores; higher anti-Ro52, anti-Ro60 and anti-La autoantibodies; higher rheumatoid factor; higher serum IgG; lower C3, lower absolute lymphocyte and neutrophil counts; (b)higher BAFF gene expression in monocytes. In addition, serum of signature-positive patients induced BAFF gene expression in monocytes. Conclusions The monocyte IFN type I signature identifies a subgroup of patients with pSS with a higher clinical disease activity together with higher BAFF mRNA expression. Such patients might benefit from treatment blocking IFN type I production or activity. PMID:22736090

  16. Therapeutic Effects of PADRE-BAFF Autovaccine on Rat Adjuvant Arthritis

    PubMed Central

    Feng, Guo-dong; Xue, Xiao-chang; Gao, Mei-li; Wang, Xian-feng; Shu, Zhen; Mu, Nan; Gao, Yuan; Wang, Zeng-lu; Hao, Qiang; Li, Wei-na; Li, Meng; Zhang, Cun; Zhang, Wei; Zhang, Ying-qi

    2014-01-01

    B cell activating factor (BAFF) is a cytokine of tumor necrosis factor family mainly produced by monocytes and dendritic cells. BAFF can regulate the proliferation, differentiation, and survival of B lymphocytes by binding with BAFF-R on B cell membrane. Accumulating evidences showed that BAFF played crucial roles and was overexpressed in various autoimmune diseases such as systemic lupus erythematous (SLE) and rheumatoid arthritis (RA). This suggests that BAFF may be a therapeutic target for these diseases. In the present study, we developed a BAFF therapeutic vaccine by coupling a T helper cell epitope AKFVAAWTLKAA (PADRE) to the N terminus of BAFF extracellular domains (PADRE-BAFF) and expressed this fusion protein in Escherichia coli. The purified vaccine can induce high titer of neutralizing BAFF antibodies and ameliorate the syndrome of complete Freund's adjuvant (CFA) induced rheumatoid arthritis in rats. Our data indicated that the BAFF autovaccine may be a useful candidate for the treatment of some autoimmune diseases associated with high level of BAFF. PMID:24791002

  17. The first BAFF gene cloned from the cartilaginous fish.

    PubMed

    Ren, Wenhua; Pang, Shuying; You, Fengtao; Zhou, Lidan; Zhang, Shuangquan

    2011-12-01

    B-cell activating factor (BAFF), a member of the TNF family, is critical to the survival, proliferation, maturation, and differentiation of B-cells. In the present study, a CpBAFF was amplified from the white-spotted catshark (Chiloscyllium plagiosum) using RT-PCR and RACE (rapid amplification of cDNA end) techniques. To our knowledge, this is the first report of any BAFF gene being cloned from a cartilaginous fish. The open reading frame (ORF) of CpBAFF cDNA consists of 819 bases encoding a protein of 272 amino acids. This protein was found to contain a predicted transmembrane domain, a putative furin protease cleavage site, and a typical TNF homology domain corresponding to other identified BAFF homologues. Sequence alignment showed that CpBAFF shares 37-57% identity with BAFF amino acid sequences reported in other vertebrates. Three-dimensional structure modeling analysis revealed a soluble mature portion of CpBAFF (CpsBAFF) with a long D-E loop specific to the BAFF gene, which has not been found in other reported TNF proteins. Phylogenetic reconstruction showed that CpBAFF is most closely related to other fish BAFFs and clusters with BAFF genes from higher vertebrates (reptiles, birds, and mammals). Real-time quantitative RT-PCR demonstrated that CpBAFF mRNA expression was high in the spleen but moderate in the kidney and branchia. Recombinant CpsBAFF fused to NusA-His(6)-tag was efficiently expressed in Escherichia coli BL21 (DE3), and a molecular weight of approximately 83 kDa was determined using SDS-PAGE and Western blotting. In vitro MTT assay indicated that the purified pET43.1a (+)-CpsBAFF protein can co-stimulate the proliferation of mammalian B-cells with anti-IgM in a dose-dependent manner. The present findings not only present novel information that may be relevant to shark immunity but also provide some new insights into the origins and evolution of immunity in all vertebrates.

  18. IgG4-related epididymo-orchitis associated with bladder cancer: possible involvement of BAFF/BAFF-R interaction in IgG4-related urogenital disease.

    PubMed

    Migita, Kiyoshi; Miyashita, Taiichiro; Mizuno, Aya; Jiuchi, Yuka; Ito, Masahiro; Matsuo, Manabu; Izumi, Yasumori; Takeoka, Atsushi; Nishino, Ayako; Hayashi, Mikio

    2014-01-01

    We describe herein a patient who presented with immunoglobulin G4-related disease (IgG4-RD) involving the testis and prostate as well as the submandibular glands. Massive infiltration of IgG4-expressing plasma cells was observed in testis and prostate tissues. Serum concentrations of B cell activating factor belonging to the tumor necrosis factor family (BAFF) were elevated in parallel with serum IgG4 concentrations, and infiltration of BAFF-receptor (BAFF-R)-expressing B cells and BAFF-expressing lymphoid cells was observed around the ectopic lymphoid foci in the affected urogenital tissues. To date, testicular involvement in a patient diagnosed with IgG4-RD had not been reported, making this the first reported case of IgG4-related epididymo-orchitis. These findings suggest that the immune mechanism underlying ectopic lymphoneogenesis in IgG4-RD may involve enhanced BAFF/BAFF-R interactions among lymphoid cells.

  19. Efficient generation of antigen-specific CTLs by the BAFF-activated human B Lymphocytes as APCs: a novel approach for immunotherapy

    PubMed Central

    Yingshi, Chen; Lishi, Su; Baohong, Luo; Chao, Liu; Linghua, Li; Ting, Pan; Hui, Zhang

    2016-01-01

    Efficient antigen presentation is indispensable for cytotoxic T lymphocyte (CTL)-mediated immunotherapy. B-lymphocytes propagated with CD40L have been developed as antigen-presenting cells (APCs), but this capacity needs further optimization. Here, we aimed to expand human B-lymphocytes on a large scale while maintaining their antigen-presenting ability by using both CD40L and B-cell activating factor (BAFF). The addition of BAFF enhanced the expansion efficiency and prolonged the culture time without causing apoptosis of the expanded B-cells. This method thus provided an almost unlimited source of cellular adjuvant to achieve sufficient expansion of CTLs in cases where several rounds of stimulation are required. We also showed that the addition of BAFF significantly enhanced the expression of major costimulatory molecules, CD80 and CD86. Subsequently, the antigen-presenting ability of the B-lymphocytes also increased. Consequently, these B-lymphocytes showed robust CTL responses to inhibit tumor growth after tumor-specific peptide pulses. A similar method induced potent antigen-specific CTL responses, which effectively eradicated human immunodeficiency virus type 1 (HIV-1) latency in CD4 T-lymphocytes isolated from patients receiving suppressive anti-retroviral therapy (ART). Together, our findings indicate that potent antigen-specific CTLs can be generated using BAFF-activated B-lymphocytes as APCs ex vivo. This approach can be applied for CTL-mediated immunotherapy in patients with cancers or chronic viral infections. PMID:27780916

  20. Clinical Significance of Pre- and Post-Transplant BAFF Levels in Kidney Transplant Recipients

    PubMed Central

    Min, Ji Won; Kim, Kyoung Woon; Kim, Bo-Mi; Doh, Kyoung Chan; Choi, Min Seok; Choi, Bum Soon; Park, Cheol Whee; Yang, Chul Woo; Kim, Yong-Soo

    2016-01-01

    It is well known that pre-transplant B cell activating factor (BAFF) levels are associated with the development of de novo anti-HLA antibodies and antibody mediated rejection post-transplant. However, the clinical significance of BAFF values at allograft rejection has not been determined. In this study, we investigated the clinical significance of pre-transplant BAFF level as well as post-transplant BAFF levels measured when indication biopsy was done. We checked for anti-HLA antibodies in 115 kidney transplant recipients who required allograft biopsy due to an increase in serum creatinine. With the same serum specimen, we measured BAFF levels, and in 78 of these patients, pre-transplant BAFF and anti-HLA antibody levels were detected as well. Patients in each group were divided into tertiles according to BAFF levels. We investigated the relationship between BAFF levels and the occurrence of anti-HLA antibodies. Pre-transplant BAFF levels showed significant association with pre-transplant sensitization, and also with early rejection (Tertile 3, 26.9% vs. Tertile 1, 11.5%; P<0.05). Post-transplant BAFF levels showed significant association with pre-transplant sensitization, but did not show association with anti-HLA antibodies and positive donor-specific antibodies at the time of biopsy. We did not find any association between post-transplant BAFF levels and allograft biopsy results, Banff scores and microvascular inflammation scores. In conclusion, pre-transplant BAFF levels are associated with pre-transplant sensitization and are useful in predicting allograft rejection. But post-transplant BAFF levels measured at the time of indication biopsy are not associated with the appearance of de novo HLA-DSA, allograft rejection, biopsy findings and other allograft outcomes. PMID:27631619

  1. Stromal endothelial cells establish a bidirectional crosstalk with chronic lymphocytic leukemia cells through the TNF-related factors BAFF, APRIL and CD40L

    PubMed Central

    Cols, Montserrat; Barra, Carolina M.; He, Bing; Puga, Irene; Xu, Weifeng; Chiu, April; Tam, Wayne; Knowles, Daniel M.; Dillon, Stacey R.; Leonard, John P.; Furman, Richard R.; Chen, Kang; Cerutti, Andrea

    2012-01-01

    Chronic lymphocytic leukemia (CLL) is a clonal B cell disorder of unknown origin. Accessory signals from the microenvironment are critical for the survival, expansion and progression of malignant B cells. We found that the CLL stroma included microvascular endothelial cells (MVECs) expressing BAFF and APRIL, two TNF family members related to the T cell-associated B cell-stimulating molecule CD40 ligand (CD40L). Constitutive release of soluble BAFF and APRIL increased upon engagement of CD40 on MVECs by CD40L aberrantly expressed on CLL cells. In addition to enhancing MVEC expression of the CD40 receptor, leukemic CD40L induced cleavases that elicited intracellular processing of pro-BAFF and pro-APRIL proteins in MVECs. The resulting soluble BAFF and APRIL proteins delivered survival, proliferation, Ig gene-remodeling and differentiation signals by activating CLL cells through TACI, BAFF-R and BCMA receptors. BAFF and APRIL further amplified CLL cell survival by up-regulating the expression of leukemic CD40L. Inhibition of TACI, BCMA and BAFF-R expression on CLL cells, abrogation of CD40 expression in MVECs, or suppression of BAFF and APRIL cleavases in MVECs reduced the survival and diversification of malignant B cells. These data indicate that BAFF, APRIL and CD40L form a CLL-enhancing bidirectional signaling network linking neoplastic B cells with the microvascular stroma. PMID:22593611

  2. A pathway switch directs BAFF signaling to distinct NFκB transcription factors in maturing and proliferating B cells.

    PubMed

    Almaden, Jonathan V; Tsui, Rachel; Liu, Yi C; Birnbaum, Harry; Shokhirev, Maxim N; Ngo, Kim A; Davis-Turak, Jeremy C; Otero, Dennis; Basak, Soumen; Rickert, Robert C; Hoffmann, Alexander

    2014-12-24

    BAFF, an activator of the noncanonical NFκB pathway, provides critical survival signals during B cell maturation and contributes to B cell proliferation. We found that the NFκB family member RelB is required ex vivo for B cell maturation, but cRel is required for proliferation. Combined molecular network modeling and experimentation revealed Nfkb2 p100 as a pathway switch; at moderate p100 synthesis rates in maturing B cells, BAFF fully utilizes p100 to generate the RelB:p52 dimer, whereas at high synthesis rates, p100 assembles into multimeric IκBsome complexes, which BAFF neutralizes in order to potentiate cRel activity and B cell expansion. Indeed, moderation of p100 expression or disruption of IκBsome assembly circumvented the BAFF requirement for full B cell expansion. Our studies emphasize the importance of p100 in determining distinct NFκB network states during B cell biology, which causes BAFF to have context-dependent functional consequences.

  3. Intravenous immunoglobulin inhibits BAFF production in chronic inflammatory demyelinating polyneuropathy - a new mechanism of action?

    PubMed

    Bick, Sandra; Tschernatsch, Marlene; Karg, Anne; Fuehlhuber, Verena; Trenczek, Tina E; Faltermeier, Kathrin; Hackstein, Holger; Kaps, Manfred; Blaes, Franz

    2013-03-15

    Chronic-inflammatory demyelinating polyneuropathy (CIDP) is an immune-mediated disease treated with intravenous immunoglobulin (IVIg). The underlying mechanism of action remains incompletely understood. The B-cell activating factor BAFF contributes to B-cell homeostasis and (auto-)antibody production. BAFF was recently identified as one key molecule in the development of autoimmune diseases. Herein, we demonstrate that BAFF serum levels are elevated in CIDP patients. IVIg treatment resulted in a significant decrease of BAFF serum level. In vitro, IVIg inhibited BAFF in monocytes. Consequently, we identified BAFF as a new target for IVIg in CIDP treatment and provide a new, Fcγ-receptor independent, mechanism of action for IVIg.

  4. Identify the key amino acid of BAFF binding with TACI.

    PubMed

    Wang, Renxi; Wang, Ru; Ma, Ning; Guo, Yueling; Xiao, He; Chen, Guojiang; Han, Gencheng; Hou, Chunmei; Shen, Beifen; Feng, Jiannan; Li, Yan

    2013-01-01

    B-cell activating factor (BAFF) has been used as a therapeutic target. To develop BAFF-specific small molecular inhibitors, it is necessary to know the key amino acid in the BAFF binding with its receptor. The key binding amino acid of BAFF interacting with its receptor TACI (trans-membrane activator and calcium modulator and cyclophilin ligand interactor) was analyzed based on the computer-guided molecular modeling method. According to theoretical prediction, a series of key amino acid mutants of BAFF, including M204 (Lys(204) to Ala), M208 (Met(208) to Ala), M209 (Gly(209) to Ala), M210 (His(210) to Ala), M234 (Gln(234) to Ala), M236 (Met(236) to Ala), and M237 (Pro(237) to Ala) were designed and evaluated with biological experiments. The results show that M208, M209, M236, and M237 of BAFF were the key amino acids and in accord with the theoretical results. The results highlight clues for the further development of BAFF-specific small molecular inhibitors.

  5. Signals from activation of B-cell receptor with anti-IgD can override the stimulatory effects of excess BAFF on mature B cells in vivo.

    PubMed

    Nguyen, Tue G; Morris, Jonathan M

    2014-09-01

    The selection and maturation of B-cell clones are critically determined by tonic signals from activated B cell receptors (BCR) and survival signals from BAFF cytokine. These finely tuned and coordinated signals provide a net positive signal that can promote the selection, maturation, proliferation and differentiation of a developing B cell. Stimulation with an anti-IgD antibody can also activate BCR but can lead to depletion and an arrest of mature B-cell development in vivo. It is not known whether survival signals from excess BAFF can override the suppressive effects of treatment with anti-IgD on mature B cells in vivo. Herein, we examined the effects of co-treatment of BAFF and anti-IgD on the mature B-cell compartment and antibody production in vivo by treating mice with either 1mg/kg BAFF or anti-IgD alone or in combination for 3 consecutive days. We found that co-treatment with anti-IgD significantly abrogated these stimulatory effects of BAFF treatment on splenic CD19+ B cells as well as mature CD19+IgD(hi)IgM+ B cells in vivo. Anti-IgD down-regulated the expression of the BCR complex (mIgM, mIgD and CD19) and the BAFF receptor TACI without regard to the presence of BAFF. Anti-IgD treatment also significantly negated BAFF-induced IgM production in vivo. Both BAFF and anti-IgD could individually stimulate IL-10 synthesis in B cells but did not affect one another. Taken together, our data suggest that activation of BCR with an anti-IgD antibody can override the stimulatory effects from excess BAFF on B cell proliferation and antibody production by down-regulating the expression of BCR complex and BAFF receptors.

  6. Expression profile of BAFF in peripheral blood from patients of IgA nephropathy: Correlation with clinical features and Streptococcus pyogenes infection.

    PubMed

    Zheng, Nuoyan; Fan, Jinjin; Wang, Bing; Wang, Dongxian; Feng, Pinning; Yang, Qiongqiong; Yu, Xueqing

    2017-04-01

    B cells are critically important for the pathogenesis of IgA nephropathy (IgAN). The present study aimed to investigate the abundance of B cell activating factor (BAFF), which belongs to the tumor necrosis factor superfamily, in the peripheral blood of patients with IgAN. The different forms of BAFF in peripheral blood and its association with clinical features and immunological factors were analyzed. mRNA levels of BAFF and other associated genes in the peripheral blood mononuclear cells (PBMCs) of patients with IgAN and controls were analyzed by quantitative polymerase chain reaction. Cellular BAFF proteins in PBMCs and plasma soluble BAFF proteins were measured by western blot analysis and ELISA, respectively. PBMCs from patients were stimulated with Streptococcus pyogenes (S. pyogenes) ex vivo for the BAFF secretion assay. The data demonstrated that, although mRNA levels of BAFF in PBMC were not significantly increased in patients with IgAN, they were positively associated with those of a proliferation inducing ligand (APRIL), Toll‑like receptor (TLR)2, TLR4 and TLR7. The cellular BAFF protein in PBMCs was not upregulated. Plasma BAFF protein levels in patients with IgAN (n=76) were significantly decreased compared with controls. However, plasma BAFF levels were positively associated with serum creatinine, proteinuria, uric acid and group A Streptococcus infection index in patients with IgAN. In patients with IgAN, plasma BAFF concentrations were markedly higher in those with more severe renal tubular atrophy/interstitial fibrosis and global glomerulosclerosis. Furthermore, BAFF production in PBMCs of patients with IgAN was increased following S. pyogenes stimulation ex vivo. In conclusion, plasma BAFF levels in patients with IgAN were associated with renal function and disease activity. S. pyogenes infection was closely associated with BAFF production in patients with IgAN.

  7. IFN type I and II induce BAFF secretion from human decidual stromal cells.

    PubMed

    Lundell, Anna-Carin; Nordström, Inger; Andersson, Kerstin; Lundqvist, Christina; Telemo, Esbjörn; Nava, Silvia; Kaipe, Helen; Rudin, Anna

    2017-01-06

    B cell activating factor (BAFF) is a critical cytokine for maturation of immature B cells. In murine lymph nodes, BAFF is mainly produced by podoplanin-expressing stromal cells. We have previously shown that circulating BAFF levels are maximal at birth, and that farmers' children exhibit higher BAFF levels in cord blood than non-farmers' children. Here, we sought to investigate whether maternal-derived decidual stromal cells from placenta secrete BAFF and examine what factors could stimulate this production. We found that podoplanin is expressed in decidua basalis and in the underlying villous tissue as well as on isolated maternal-derived decidual stromal cells. Decidual stromal cells produced BAFF when stimulated with IFN-γ and IFN-α, and NK cells and NK-T-like cells competent of IFN-γ production were isolated from the decidua. Finally, B cells at different maturational stages are present in decidua and all expressed BAFF-R, while stromal cells did not. These findings suggest that decidual stromal cells are a cellular source of BAFF for B cells present in decidua during pregnancy.

  8. IFN type I and II induce BAFF secretion from human decidual stromal cells

    PubMed Central

    Lundell, Anna-Carin; Nordström, Inger; Andersson, Kerstin; Lundqvist, Christina; Telemo, Esbjörn; Nava, Silvia; Kaipe, Helen; Rudin, Anna

    2017-01-01

    B cell activating factor (BAFF) is a critical cytokine for maturation of immature B cells. In murine lymph nodes, BAFF is mainly produced by podoplanin-expressing stromal cells. We have previously shown that circulating BAFF levels are maximal at birth, and that farmers’ children exhibit higher BAFF levels in cord blood than non-farmers’ children. Here, we sought to investigate whether maternal-derived decidual stromal cells from placenta secrete BAFF and examine what factors could stimulate this production. We found that podoplanin is expressed in decidua basalis and in the underlying villous tissue as well as on isolated maternal-derived decidual stromal cells. Decidual stromal cells produced BAFF when stimulated with IFN-γ and IFN-α, and NK cells and NK-T-like cells competent of IFN-γ production were isolated from the decidua. Finally, B cells at different maturational stages are present in decidua and all expressed BAFF-R, while stromal cells did not. These findings suggest that decidual stromal cells are a cellular source of BAFF for B cells present in decidua during pregnancy. PMID:28057926

  9. Soluble BAFF Cytokine Levels and Antibody-Mediated Rejection of the Kidney Allograft.

    PubMed

    Slavcev, Antonij; Brozova, Jitka; Slatinska, Janka; Sekerkova, Zuzana; Honsova, Eva; Skibova, Jelena; Striz, Ilja; Viklicky, Ondrej

    2016-12-01

    The B-cell activating factor (BAFF) cytokine has important functions for the survival and maturation of B lymphocytes, which implies that this cytokine might play a role in the development of antibody-mediated rejection (AMR) after kidney transplantation. In our study, we compared the concentrations of the soluble BAFF cytokine in kidney graft recipients with AMR and patients without rejection with the goal of testing the hypothesis whether BAFF level measurement might be useful as a diagnostic marker of AMR. The study included a cohort of 19 high-risk patients with diagnosed AMR and 17 control patients free of rejection. BAFF was measured in all patients before transplantation, during the rejection episodes, and three months after transplantation in patients free of rejection using the Luminex technique. Before transplantation, the serum concentrations of BAFF in patients with AMR and kidney recipients without rejection did not significantly differ. After transplantation, however, BAFF levels were significantly lower in patients with AMR and also in patients with concurrent humoral and cellular rejection compared with patients without rejection (p < 0.05 and p < 0.01, respectively). No correlation was found between BAFF and the production of donor-specific antibodies (DSA) before and after transplantation. Patients experiencing AMR and simultaneous cellular and AMR had significantly lower concentrations of BAFF in comparison with patients free of rejection.

  10. Serum BAFF levels, Methypredsinolone therapy, Epstein-Barr Virus and Mycobacterium avium subsp. paratuberculosis infection in Multiple Sclerosis patients.

    PubMed

    Mameli, Giuseppe; Cocco, Eleonora; Frau, Jessica; Arru, Giannina; Caggiu, Elisa; Marrosu, Maria Giovanna; Sechi, Leonardo A

    2016-07-07

    Elevated B lymphocyte activating factor BAFF levels have been reported in multiple sclerosis (MS) patients; moreover, disease-modifying treatments (DMT) have shown to influence blood BAFF levels in MS patients, although the significance of these changes is still controversial. In addition, BAFF levels were reported increased during infectious diseases. In our study, we wanted to investigate on the serum BAFF concentrations correlated to the antibody response against Mycobacterium avium subspecies paratuberculosis (MAP), Epstein-Barr virus (EBV) and their human homologous epitopes in MS and in patients affected with other neurological diseases (OND), divided in Inflammatory Neurological Diseases (IND), Non Inflammatory Neurological Diseases (NIND) and Undetermined Neurological Diseases (UND), in comparison to healthy controls (HCs). Our results confirmed a statistically significant high BAFF levels in MS and IND patients in comparison to HCs but not NIND and UND patients. Interestingly, BAFF levels were inversely proportional to antibodies level against EBV and MAP peptides and the BAFF levels significantly decreased in MS patients after methylprednisolone therapy. These results implicate that lower circulating BAFF concentrations were present in MS patients with humoral response against MAP and EBV. In conclusion MS patients with no IgGs against EBV and MAP may support the hypothesis that elevated blood BAFF levels could be associated with a more stable disease.

  11. Serum BAFF levels, Methypredsinolone therapy, Epstein-Barr Virus and Mycobacterium avium subsp. paratuberculosis infection in Multiple Sclerosis patients

    PubMed Central

    Mameli, Giuseppe; Cocco, Eleonora; Frau, Jessica; Arru, Giannina; Caggiu, Elisa; Marrosu, Maria Giovanna; Sechi, Leonardo A.

    2016-01-01

    Elevated B lymphocyte activating factor BAFF levels have been reported in multiple sclerosis (MS) patients; moreover, disease-modifying treatments (DMT) have shown to influence blood BAFF levels in MS patients, although the significance of these changes is still controversial. In addition, BAFF levels were reported increased during infectious diseases. In our study, we wanted to investigate on the serum BAFF concentrations correlated to the antibody response against Mycobacterium avium subspecies paratuberculosis (MAP), Epstein-Barr virus (EBV) and their human homologous epitopes in MS and in patients affected with other neurological diseases (OND), divided in Inflammatory Neurological Diseases (IND), Non Inflammatory Neurological Diseases (NIND) and Undetermined Neurological Diseases (UND), in comparison to healthy controls (HCs). Our results confirmed a statistically significant high BAFF levels in MS and IND patients in comparison to HCs but not NIND and UND patients. Interestingly, BAFF levels were inversely proportional to antibodies level against EBV and MAP peptides and the BAFF levels significantly decreased in MS patients after methylprednisolone therapy. These results implicate that lower circulating BAFF concentrations were present in MS patients with humoral response against MAP and EBV. In conclusion MS patients with no IgGs against EBV and MAP may support the hypothesis that elevated blood BAFF levels could be associated with a more stable disease. PMID:27383531

  12. B cell activating factor is central to bleomycin- and IL-17-mediated experimental pulmonary fibrosis.

    PubMed

    François, Antoine; Gombault, Aurélie; Villeret, Bérengère; Alsaleh, Ghada; Fanny, Manoussa; Gasse, Paméla; Adam, Sylvain Marchand; Crestani, Bruno; Sibilia, Jean; Schneider, Pascal; Bahram, Seiamak; Quesniaux, Valérie; Ryffel, Bernhard; Wachsmann, Dominique; Gottenberg, Jacques-Eric; Couillin, Isabelle

    2015-01-01

    Idiopathic pulmonary fibrosis (IPF) is a progressive devastating, yet untreatable fibrotic disease of unknown origin. We investigated the contribution of the B-cell activating factor (BAFF), a TNF family member recently implicated in the regulation of pathogenic IL-17-producing cells in autoimmune diseases. The contribution of BAFF was assessed in a murine model of lung fibrosis induced by airway administered bleomycin. We show that murine BAFF levels were strongly increased in the bronchoalveolar space and lungs after bleomycin exposure. We identified Gr1(+) neutrophils as an important source of BAFF upon BLM-induced lung inflammation and fibrosis. Genetic ablation of BAFF or BAFF neutralization by a soluble receptor significantly attenuated pulmonary fibrosis and IL-1β levels. We further demonstrate that bleomycin-induced BAFF expression and lung fibrosis were IL-1β and IL-17A dependent. BAFF was required for rIL-17A-induced lung fibrosis and augmented IL-17A production by CD3(+) T cells from murine fibrotic lungs ex vivo. Finally we report elevated levels of BAFF in bronchoalveolar lavages from IPF patients. Our data therefore support a role for BAFF in the establishment of pulmonary fibrosis and a crosstalk between IL-1β, BAFF and IL-17A.

  13. Serum BAFF and APRIL levels in patients with autoimmune hemolytic anemia and their clinical significance.

    PubMed

    Xu, Zi-Zhen; Zhao, Bing-Bing; Xiong, Hong; Wei, Bei-Wen; Wang, Ye-Fei

    2015-10-01

    B cell-activating factor of the tumor necrosis factor family (BAFF) and a proliferation-inducing ligand (APRIL) play crucial roles in B cell development, survival, and antibody production. Autoimmune hemolytic anemia (AIHA) is an acquired autoimmune disease that occurs when antibodies target autologous red blood cells. Here, we analyzed the serum levels of BAFF and APRIL and their respective clinical associations in patients with AIHA. Serum BAFF and APRIL levels in patients with AIHA were significantly higher (P < 0.01) than in healthy individuals. Serum BAFF and APRIL levels were significantly augmented in patients with lower hemoglobin levels (hemoglobin was <8 g/dL) and higher LDH activity (LDH > 480 IU/mL). Glucocorticoid treatment dramatically reduced serum levels of BAFF and APRIL. Thus, serum BAFF and APRIL levels may reflect the clinical activity of this disease. Our results indicate that analysis of serum concentrations of BAFF and APRIL potentially represents a useful tool for the assessment of AIHA disease activity and progression.

  14. Myeloid cells, BAFF, and IFN-γ establish an inflammatory loop that exacerbates autoimmunity in Lyn-deficient mice

    PubMed Central

    Scapini, Patrizia; Hu, Yongmei; Chu, Ching-Liang; Migone, Thi-Sau; DeFranco, Anthony L.; Cassatella, Marco A.

    2010-01-01

    Autoimmunity is traditionally attributed to altered lymphoid cell selection and/or tolerance, whereas the contribution of innate immune cells is less well understood. Autoimmunity is also associated with increased levels of B cell–activating factor of the TNF family (BAFF; also known as B lymphocyte stimulator), a cytokine that promotes survival of self-reactive B cell clones. We describe an important role for myeloid cells in autoimmune disease progression. Using Lyn-deficient mice, we show that overproduction of BAFF by hyperactive myeloid cells contributes to inflammation and autoimmunity in part by acting directly on T cells to induce the release of IFN-γ. Genetic deletion of IFN-γ or reduction of BAFF activity, achieved by either reducing myeloid cell hyperproduction or by treating with an anti-BAFF monoclonal antibody, reduced disease development in lyn−/− mice. The increased production of IFN-γ in lyn−/− mice feeds back on the myeloid cells to further stimulate BAFF release. Expression of BAFF receptor on T cells was required for their full activation and IFN-γ release. Overall, our data suggest that the reciprocal production of BAFF and IFN-γ establishes an inflammatory loop between myeloid cells and T cells that exacerbates autoimmunity in this model. Our findings uncover an important pathological role of BAFF in autoimmune disorders. PMID:20624892

  15. B-lymphocyte activating factor levels are increased in patients with Wegener's granulomatosis and inversely correlated with ANCA titer.

    PubMed

    Bader, Lucius; Koldingsnes, Wenche; Nossent, Johannes

    2010-09-01

    Circulating autoantibodies against neutrophils (ANCA) are a distinctive finding in patients with Wegener's granulomatosis (WG). B-lymphocyte activating factor (BAFF) promotes autoantibody production by increasing B cell survival and proliferation. We investigated serum BAFF levels (s-BAFF) in a WG patient cohort in relation to ANCA titers and disease activity. Baseline data were obtained in twenty-two WG patients (55% female, age 44 years, disease duration 1 year). S-BAFF was determined by capture ELISA and associations between s-BAFF, clinical (Birmingham Vasculitis Activity Score (BVAS), Vasculitis Damage Index (VDI) and Disease Extent Index (DEI)) and biochemical (C-reactive protein (CRP), IgG and ANCA) disease measures were analysed in a cross sectional as well as longitudinal analysis. S-BAFF was increased in WG patients compared to healthy controls (1.8 vs. 0.55 ng/ml, p < 0.01). S-BAFF was higher in ANCA negative than ANCA-positive WG sera (2.16 vs. 1.29 ng/ml, p < 0.01), correlated independently and inversely with ANCA levels (Rs -0.48, p < 0.01) but did not correlate with CRP, BVAS, DEI or VDI scores. Individual s-BAFF profiles were stable over time in 68% of patients. The finding of a negative correlation between ANCA levels and s-BAFF that is independent of steroid treatment indicates that BAFF does not directly drive ANCA production in WG.

  16. Increased serum concentration of BAFF/APRIL and IgA2 subclass in patients with mixed connective tissue disease complicated by interstitial lung disease.

    PubMed

    Kaneko, Toshiyuki; Amano, Hirofumi; Kawano, Shinya; Minowa, Kentaro; Ando, Seiichiro; Watanabe, Takashi; Nakano, Soichiro; Suzuki, Jun; Morimoto, Shinji; Tokano, Yoshiaki; Takasaki, Yoshinari

    2014-03-01

    B cell activating factor (BAFF) and a proliferation-inducing ligand (APRIL) are known to be crucial for B cell maturation and survival, and increased expression of these factors in various autoimmune diseases has been reported. Human B cells produce two IgA subclasses: IgA1 and IgA2, the latter being abundant in the distal intestine, saliva, colostrum and bronchial fluid. We investigated these parameters in patients with mixed connective tissue disease (MCTD) complicated by interstitial lung disease (ILD+), and compared them with those in MCTD patients without ILD (ILD-). Sixty-three MCTD patients were divided into two groups: 21 ILD+ patients and 42 ILD- patients. In each patient group we analyzed soluble BAFF/APRIL using ELISA, and IgA1 and IgA2 using double immunodiffusion. Furthermore, we analyzed BAFF-APRIL receptors, BCMA, BAFF-R and TACI, using flow cytometry. The ILD+ patients had significantly higher levels of BAFF/APRIL than the ILD- patients. There were significant correlations between BAFF/APRIL, BAFF/KL-6 and APRIL/KL-6. Although there was no significant inter-group difference in the serum IgA1 level, ILD+ patients had a significantly elevated IgA2 level in comparison with ILD- patients. Moreover, although there were no significant inter-group differences in the expression of BCMA, BAFF-R and TACI on B cells, the expression of BAFF-R was significantly decreased in the ILD+ patients. In recent years, relationships between BAFF/APRIL and IgA subclass have been reported. Our results suggest that an elevated level of BAFF/APRIL drives the maturation of B cells, subsequently leading to IgA2 class switching, and possibly to the development of ILD in patients with MCTD.

  17. Differential requirement of MALT1 for BAFF-induced outcomes in B cell subsets.

    PubMed

    Tusche, Michael W; Ward, Lesley A; Vu, Frances; McCarthy, Doug; Quintela-Fandino, Miguel; Ruland, Jurgen; Gommerman, Jennifer L; Mak, Tak W

    2009-11-23

    B cell activation factor of the TNF family (BAFF) activates noncanonical nuclear factor kappaB (NF-kappaB) heterodimers that promote B cell survival. We show that although MALT1 is largely dispensable for canonical NF-kappaB signaling downstream of the B cell receptor, the absence of MALT1 results in impaired BAFF-induced phosphorylation of NF-kappaB2 (p100), p100 degradation, and RelB nuclear translocation in B220(+) B cells. This corresponds with impaired survival of MALT1(-/-) marginal zone (MZ) but not follicular B cells in response to BAFF stimulation in vitro. MALT1(-/-) MZ B cells also express higher amounts of TRAF3, a known negative regulator of BAFF receptor-mediated signaling, and TRAF3 was found to interact with MALT1. Furthermore, phenotypes associated with overexpression of BAFF, including increased MZ B cell numbers, elevated serum immunoglobulin titers, and spontaneous germinal center formation, were found to be dependent on B cell-intrinsic MALT1 expression. Our results demonstrate a novel role for MALT1 in biological outcomes induced by BAFF-mediated signal transduction.

  18. VNAR single-domain antibodies specific for BAFF inhibit B cell development by molecular mimicry.

    PubMed

    Häsler, Julien; Flajnik, Martin F; Williams, Gareth; Walsh, Frank S; Rutkowski, J Lynn

    2016-07-01

    B cell-activating factor (BAFF) plays a dominant role in the B cell homeostasis. However, excessive BAFF promotes the development of autoreactive B-cells and several antibodies have been developed to block its activity. Bispecific antibodies with added functionality represent the next wave of biologics that may be more effective in the treatment of complex autoimmune disease. The single variable domain from the immunoglobulin new antigen receptor (VNAR) is one of the smallest antibody recognition units that could be combined with monospecific antibodies to develop bispecific agents. We isolated a panel of BAFF-binding VNARs with low nM potency from a semi-synthetic phage display library and examined their functional activity. The anti-BAFF VNARs blocked the binding of BAFF to all three of its receptors (BR3, TACI and BCMA) and the presence of the conserved DXL receptor motif found in the CDR3 regions suggests molecular mimicry as the mechanism of antagonism. One clone was formatted as an Fc fusion for functional testing and it was found to inhibit both mouse and human BAFF with equal potency ex vivo in a splenocyte proliferation assay. In mice, subchronic administration reduced the number of immature and transitional intermediates B cells and mature B cell subsets. These results indicate that VNAR single domain antibodies function as selective B-cell inhibitors and offer an alternative molecular format for targeting B-cell disorders.

  19. Gender-Specific Mechanisms Underlying the Amelioration of High-Fat Diet-Induced Glucose Intolerance in B-Cell-Activating Factor Deficient Mice

    PubMed Central

    Kim, Bobae; Hyun, Chang-Kee

    2016-01-01

    It has recently been found that B cell activating factor (BAFF) plays an important role in the regulation of energy homeostasis. We also have previously reported that BAFF deficiency reverses high-fat (HF) diet-induced glucose intolerance by potentiating adipose tissue function. In the present study, we found that BAFF deficient (BAFF-/-) mice exhibit gender-specific differences in protection against diet-induced glucose intolerance, and aimed to characterize the gender-dependent molecular alterations in energy metabolism. Under HF feeding conditions, serum BAFF level of female wild-type (WT) mice was considerably higher than that of male mice. Despite increased body weight gain, both male and female BAFF-/- mice showed significantly improved glucose tolerance compared to their WT counterparts. Expressions of genes involved in glucose transport, thermogenesis and lipid oxidation were up-regulated in brown adipose tissues of both male and female BAFF-/- mice. Interestingly, the expression of thermogenic genes in subcutaneous adipose tissue was significantly enhanced in female BAFF-/- compared to WT mice, but the difference was not observed between male BAFF-/- and WT mice. The enhanced thermogenic program was confirmed by higher protein levels of UCP1 and irisin in female BAFF-/- than in WT mice. Additionally, adiponectin production in white adipose tissues and AMPK phosphorylation in subcutaneous adipose tissue were also significantly elevated in female BAFF-/- compared to WT mice, but not in male BAFF-/- mice. Our findings define a comprehensive scenario for the enhancing effect of BAFF depletion on glucose tolerance wherein the underlying mechanism is, at least in part, gender-specific, and suggest that gender difference should be considered as an important factor in the use of BAFF blockade as a therapeutic approach for the prevention and treatment of type 2 diabetes. PMID:27814392

  20. Viral Double-Stranded RNA Triggers Ig Class Switching by Activating Upper Respiratory Mucosa B Cells through an Innate TLR3 Pathway Involving BAFF1

    PubMed Central

    Xu, Weifeng; Santini, Paul A.; Matthews, Allysia J.; Chiu, April; Plebani, Alessandro; He, Bing; Chen, Kang; Cerutti, Andrea

    2011-01-01

    Class switch DNA recombination (CSR) from IgM to IgG and IgA is crucial for antiviral immunity. Follicular B cells undergo CSR upon engagement of CD40 by CD40 ligand on CD4+ T cells. This T cell-dependent pathway requires 5–7 days, which is too much of a delay to block quickly replicating pathogens. To compensate for this limitation, extrafollicular B cells rapidly undergo CSR through a T cell-independent pathway that involves innate Ag receptors of the TLR family. We found that a subset of upper respiratory mucosa B cells expressed TLR3 and responded to viral dsRNA, a cognate TLR3 ligand. In the presence of dsRNA, mucosal B cells activated NF-κB, a transcription factor critical for CSR. Activation of NF-κB required TRIF (Toll/IL-1R domain-containing protein inducing IFN-β), a canonical TLR3 adapter protein, and caused germline transcription of downstream CH genes as well as expression of AID (activation-induced cytidine deaminase), a DNA-editing enzyme essential for CSR. Subsequent IgG and IgA production was enhanced by BAFF (B cell-activating factor of the TNF family), an innate mediator released by TLR3-expressing mucosal dendritic cells. Indeed, these innate immune cells triggered IgG and IgA responses upon exposure to dsRNA. By showing active TLR3 signaling and ongoing CSR in upper respiratory mucosa B cells from patients with CD40 signaling defects, our findings indicate that viral dsRNA may initiate frontline IgG and IgA responses through an innate TLR3-dependent pathway involving BAFF. PMID:18566393

  1. IL-7 modulates B cells survival and activation by inducing BAFF and CD70 expression in T cells.

    PubMed

    Sammicheli, Stefano; Ruffin, Nicolas; Lantto, Rebecka; Vivar, Nancy; Chiodi, Francesca; Rethi, Bence

    2012-06-01

    Interleukin-7 (IL-7) promotes the maintenance and activation of peripheral T cells, whereas it does not act directly on mature B cells due to the lack of IL-7Rα expression on these. We report here that, in spite of the insensitivity of B cells to IL-7, high concentration of IL-7 can lead to increased B cell survival and antibody production in the presence of T cells, without the use of any further B cell stimulatory signal. IL-7 promoted B cell activation through inducing CD70 expression on resting T cells, particularly on CD4+ memory cells. The interaction of CD70 molecules with the B cell costimulatory receptor CD27 led to B cell proliferation, the accumulation of CD38 + CD20- plasmablasts and antibody production. In addition, IL-7 treatment induced BAFF secretion from resting peripheral T cells thereby promoting B cell survival. IL-7 levels can increase in lymphopenic conditions, in autoimmune diseases or in patients receiving T cell regenerative IL-7 therapy. Based on our findings high IL-7 levels can lead to increased B cell activation by inducing the B cell regulatory proteins CD70 and BAFF in resting T cells. Such activity might be beneficial in short term immune-stimulatory IL-7 therapies; permanently increased IL-7 levels, on the other hand, can contribute to impaired B cell tolerance.

  2. BAFF overexpression increases lymphocytic infiltration in Sjögren's target tissue, but only inefficiently promotes ectopic B-cell differentiation.

    PubMed

    Ding, Jian; Zhang, Wei; Haskett, Scott; Pellerin, Alex; Xu, Shanqin; Petersen, Britta; Jandreski, Luke; Hamann, Stefan; Reynolds, Taylor L; Zheng, Timothy S; Mingueneau, Michael

    2016-08-01

    B-cell activating factor (BAFF) levels are increased in rheumatoid arthritis, lupus and primary Sjögren's syndrome (pSS). However, BAFF contribution to pathogenesis is not completely understood. In pSS, immune infiltration of the salivary and lacrimal glands leads to xerostomia and xerophtalmia. Glandular B cell hyperactivation, differentiation into germinal center (GC)-like structures and plasma cell accumulation are histopathological hallmarks that were attributed to increased BAFF. Here, we experimentally tested this hypothesis by overexpressing BAFF in a mouse model of pSS. BAFF overexpression enhanced lymphocytic infiltration and MHCII expression on B cells. Increased BAFF also induced B cell differentiation into GC B cells within the autoimmune target tissue. However, even in these conditions, GC B cells only accounted for <1% of glandular B cells, demonstrating that BAFF is not efficiently promoting ectopic GC formation in pSS and warranting further investigation of therapeutics targeting both BAFF and the related TNF-family member APRIL.

  3. Investigations of a rabbit (Oryctolagus cuniculus) model of systemic lupus erythematosus (SLE), BAFF and its receptors.

    PubMed

    Yang, Jiahui; Pospisil, Richard; Ray, Satyajit; Milton, Jacqueline; Mage, Rose G

    2009-12-30

    B-cell activation factor belonging to the tumor necrosis factor family (BAFF) is a major contributor to survival of B lymphocytes during development and maturation. A relationship between circulating BAFF levels and disease activity has been reported in patients with the autoimmune disease Systemic Lupus Erythematosus (SLE). Clinical trials targeting BAFF or its receptors are currently in progress. In order to further characterize a rabbit (Oryctolagus cuniculus) model of SLE, we investigated the expression of BAFF and its receptors in non-inbred, pedigreed rabbits derived from breeding and selection based on autoantibody responses. We immunized rabbits related to previous groups that developed autoantibodies and inflammatory responses after immunizations with peptides synthesized on multiple antigen-branched polylysine backbones. Blood and sera collected before immunization and after boosts were used for health monitoring, analyses of serum autoantibody responses by ELISA and immunofluorescence. Peripheral blood mononuclear cells (PBMC) were studied by flow cytometry and were the source of mRNA for quantitative PCR analyses. We hypothesized that BAFF mRNA expression and serum BAFF levels measured indirectly through BAFF receptor binding might increase in autoantibody-producing rabbits. Immunized rabbits developed elevated levels of leucocyte populations, anti-nuclear, anti-dsDNA and other autoantibodies. BR3 mRNA levels in total PBMC decreased and BAFF levels remained low and unchanged in most immunized rabbits. By flow cytometry, percentages of BAFF positive cells decreased. Percentages of transmembrane activator and CAML interactor (TACI) decreased in most rabbits from all the immunized groups. The rabbit is an important model for human autoimmune and infectious diseases, and a high quality draft rabbit genome assembly was recently completed. Human disease models developed in non-inbred pedigreed animals are better able to reflect the complexities of diseases

  4. Soluble BAFF Level Is Not Correlated to Mycobacterium avium Subspecies Paratuberculosis Antibodies and Increases After Interferon-β Therapy in Multiple Sclerosis Patients.

    PubMed

    Mameli, Giuseppe; Cossu, Davide; Caggiu, Elisa; Arru, Giannina; Niegowska, Magdalena; Cocco, Eleonora; Frau, Jessica; Marrosu, Maria Giovanna; Sechi, Leonardo A

    2016-09-01

    B cells are being recognized as one of the major players in the pathogenesis of multiple sclerosis (MS). The B cell activating factor (BAFF) system plays an essential role in B cell homeostasis and function in the periphery. Mycobacterium avium subspecies paratuberculosis (MAP) has been previously associated to MS in Sardinia. Antibodies against a MAP surface protein, MAP_2694, have been found significantly associated to MS patients, and this response was modified by interferon-β therapy. Increased BAFF levels following IFN-β therapy have been also described in MS patients. In this study, we evaluated whether soluble BAFF levels are comparable in men and women affected by MS and performed a correlation of the reported BAFF increase in MS patients under IFN-β therapy with changes of humoral response against MAP_2694. For these reasons, we investigated 44 MS patients before and after IFN-β therapy. A significant difference of BAFF levels was found between men and women with MS; moreover, we confirmed that IFN-β therapy strongly induces BAFF serum levels, but this was not related to the modification of immunological response against MAP_2694. In conclusion, our study highlights that IFN-β therapy induces the potent B cell survival factor BAFF without alterations of the humoral immune response against MAP.

  5. High Expression Levels of BLyS/BAFF by Blood Dendritic Cells and Granulocytes Are Associated with B-cell dysregulation in SIV-Infected Rhesus Macaques

    PubMed Central

    Chagnon-Choquet, Josiane; Burdo, Tricia; Autissier, Patrick; Oskar, Kathryn; Williams, Kenneth C.; Roger, Michel

    2015-01-01

    Dendritic cells (DCs) modulate B-cell survival and differentiation, mainly through production of growth factors such as B lymphocyte stimulator (BLyS/BAFF). In recent longitudinal studies involving HIV-1-infected individuals with different rates of disease progression, we have shown that DCs were altered in number and phenotype in the context of HIV-1 disease progression and B-cell dysregulations were associated with increased BLyS/BAFF expression in plasma and by blood myeloid DCs (mDCs) in rapid and classic progressors but not in HIV-1-elite controllers (EC). Suggesting that the extent to which HIV-1 disease progression is controlled may be linked to BLyS/BAFF expression status and the capacity to orchestrate B-cell responses. Herein, longitudinal analyses of simian immunodeficiency virus (SIV)-infected rhesus macaques also revealed increased expression of BLyS/BAFF by blood mDCs as soon as day 8 and throughout infection. Strikingly, granulocytes presented the highest BLyS/BAFF expression profile in the blood of SIV-infected macaques. BLyS/BAFF levels were also increased in plasma and correlated with viral loads. Consequently, these SIV-infected animals had plasma hyperglobulinemia and reduced blood B-cell numbers with altered population frequencies. These data underscore that BLyS/BAFF is associated with immune dysregulation in SIV-infected rhesus macaques and suggest that BLyS/BAFF is a key regulator of immune activation that is highly conserved among primates. These findings emphasize the potential importance of this SIV-infected primate model to test whether blocking excess BLyS/BAFF has an effect on the overall inflammatory burden and immune restoration. PMID:26107380

  6. Rapamycin Attenuates BAFF-extended Proliferation and Survival via Disruption of mTORC1/2 Signaling in Normal and Neoplastic B-lymphoid Cells.

    PubMed

    Zeng, Qingyu; Qin, Shanshan; Zhang, Hai; Liu, Beibei; Qin, Jiamin; Wang, Xiaoxue; Zhang, Ruijie; Liu, Chunxiao; Dong, Xiaoqing; Zhang, Shuangquan; Huang, Shile; Chen, Long

    2017-03-16

    B cell activating factor from the TNF family (BAFF) stimulates B-cell proliferation and survival, but excessive BAFF promotes the development of aggressive B cells leading to malignant and autoimmune diseases. Recently, we have reported that rapamycin, a macrocyclic lactone, attenuates human soluble BAFF (hsBAFF)-stimulated B-cell proliferation/survival by suppressing mTOR-mediated PP2A-Erk1/2 signaling pathway. Here, we show that the inhibitory effect of rapamycin on hsBAFF-promoted B cell proliferation/survival is also related to blocking hsBAFF-stimulated phosphorylation of Akt, S6K1 and 4E-BP1, as well as expression of survivin in normal and B-lymphoid (Raji and Daudi) cells. It appeared that both mTORC1 and mTORC2 were involved in the inhibitory activity of rapamycin, as silencing raptor or rictor enhanced rapamycin's suppression of hsBAFF-induced survivin expression and proliferation/viability in B cells. Also, PP242, an mTORC1/2 kinase inhibitor, repressed survivin expression and cell proliferation/viability more potently than rapamycin (mTORC1 inhibitor) in B cells in response to hsBAFF. Of interest, ectopic expression of constitutively active Akt (myr-Akt) or constitutively active S6K1 (S6K1-ca), or downregulation of 4E-BP1 conferred resistance to rapamycin's attenuation of hsBAFF-induced survivin expression and B-cell proliferation/viability, whereas overexpression of dominant negative Akt (dn-Akt) or constitutively hypophosphorylated 4E-BP1 (4EBP1-5A), or downregulation of S6K1, or co-treatment with Akt inhibitor potentiated the inhibitory effects of rapamycin. The findings indicate that rapamycin attenuates excessive hsBAFF-induced cell proliferation/survival via blocking mTORC1/2 signaling in normal and neoplastic B-lymphoid cells. Our data underscore that rapamycin may be a potential agent for preventing excessive BAFF-evoked aggressive B-cell malignancies and autoimmune diseases. This article is protected by copyright. All rights reserved.

  7. The Effects of Jieduquyuzishen Prescription-Treated Rat Serum on the BAFF/BAFF-R Signal Pathway

    PubMed Central

    Wen, Cheng-ping; Xie, Guan-qun; Ji, Jin-jun; Pan, Jie-li; Jiao, Yi-feng; Fan, Yong-sheng

    2015-01-01

    Systemic lupus erythematosus (SLE) is a chronic inflammatory disease mainly characterized by B cell hyperactivity. Glucocorticoid (GC) is widely used in SLE for its potent anti-inflammatory and immunosuppressive effects. Despite its important clinical efficacy, high-dose or long-term use of GC can cause severe side effects, such as osteoporosis, osteonecrosis, cataracts, hyperglycemia, coronary heart disease and cognitive impairment. Our early clinical studies have shown that Jieduquyuzishen prescription (JP) can effectively reduce the adverse effects and improve the curative effect of GC in the treatment of SLE. The BAFF/BAFF-R signaling pathway plays an important role in the development of SLE and has been regarded as a potential target for the therapy of SLE. In this study, we attempt to investigate the effect of JP on the BAFF/BAFF-R signaling pathway to explore the mechanism of JP in reducing the toxicity and enhancing the efficacy of GC. YAC-1 cells, isolated rat peripheral blood lymphocytes, polymorphonuclear neutrophils and spleen lymphocytes were treated with drug-containing serum. The results of RT-PCR, Western blot and dual-luciferase reporter gene assays indicate that either JP or GC can inhibit the mBAFF-induced up-regulation of BAFF, BAFF-R, Bcl-2, IL-10 and NF-κB in YAC-1 cells and WEHI-231 cells. Furthermore, MTS, flow cytometry and CFSE results reveal that the proliferation and survival of lymphocytes activated by mBAFF are suppressed by JP, GC and their combination. Contrary to GC, JP can reduce the apoptosis and raise the survival of polymorphonuclear neutrophils and can’t increase the apoptosis of the peripheral blood lymphocytes and spleen lymphocytes. Therefore, it is possible that JP can down-regulate the BAFF/BAFF-R signaling pathway as effectively as GC, which may result in the dosage reduction of GC, thus decreasing the toxicity and improving the efficacy of GC-based treatment of SLE. PMID:25689512

  8. Effector-mediated eradication of precursor B acute lymphoblastic leukemia with a novel Fc engineered monoclonal antibody targeting the BAFF-R

    PubMed Central

    Parameswaran, Reshmi; Lim, Min; Fei, Fei; Abdel-Azim, Hisham; Arutyunyan, Anna; Schiffer, Isabelle; McLaughlin, Margaret E.; Gram, Hermann; Huet, Heather; Groffen, John; Heisterkamp, Nora

    2014-01-01

    B-cell activating factor receptor (BAFF-R) is expressed on precursor B acute lymphoblastic leukemia ALL (pre-B ALL) cells but not on their pre-B normal counterparts. Thus, selective killing of ALL cells is possible by targeting this receptor. Here we have further examined therapeutic targeting of pre-B ALL based on the presence of the BAFF-R. Mouse pre-B ALL cells lacking BAFF-R function had comparable viability and proliferation to wild type cells but were more sensitive to drug treatment. Viability of human pre-B ALL cells was further reduced when antibodies to the BAFF-R were combined with other drugs, even in the presence of stromal protection. This indicates that inhibition of BAFF-R function reduces fitness of stressed pre-B ALL cells. We tested a novel humanized anti-BAFF-R monoclonal antibody optimalized for FcRγIII mediated, antibody-dependent cell killing by effector cells. Antibody binding to human ALL cells was inhibitable, in a dose-dependent manner, by recombinant human BAFF. There was no evidence for internalization of the antibodies. The antibodies significantly stimulated NK cell-mediated killing of different human patient-derived ALL cells. Moreover, incubation of such ALL cells with these antibodies stimulated phagocytosis by macrophages. When this was tested in an immunodeficient transplant model, mice that were treated with the antibody had a significantly decreased leukemia burden in bone marrow and spleen. In view of the restricted expression of the BAFF-R on normal cells and the multiple anti-pre-B ALL activities stimulated by this antibody, a further examination of its use for treatment of pre-B ALL is warranted. PMID:24825858

  9. Raised cerebrospinal fluid BAFF and APRIL levels in anti-N-methyl-d-aspartate receptor encephalitis: Correlation with clinical outcome.

    PubMed

    Deng, Bo; Liu, Xiao-Ni; Li, Xiang; Zhang, Xiang; Quan, Chao; Chen, Xiang-Jun

    2017-04-15

    In this study, we aimed to assess the levels of B cell activating factor from the tumor necrosis factor family (BAFF) and a proliferation-inducing ligand (APRIL) in cerebrospinal fluid (CSF) of patients with anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis and determine their correlation with clinical outcome. BAFF and APRIL concentrations in CSF and serum from 40 patients with anti-NMDAR encephalitis and 20 controls were measured by enzyme-linked immunosorbent assay (ELISA). Compared with controls, the levels of both BAFF and APRIL in CSF were significantly increased in patients with anti-NMDAR encephalitis (p<0.001 and p<0.001). Patients with unfavorable outcome had higher levels of BAFF and APRIL in CSF than those who had favorable outcome (p<0.05 and p<0.05). BAFF and APRIL levels in CSF were elevated and associated with clinical outcome in patients with anti-NMDAR encephalitis, indicating that they may be valuable biomarkers to this disease.

  10. Synovial cell death is regulated by TNF-α-induced expression of B-cell activating factor through an ERK-dependent increase in hypoxia-inducible factor-1α.

    PubMed

    Lee, Jae-Wook; Lee, Jiyoung; Um, Sung Hee; Moon, Eun-Yi

    2017-04-06

    B-cell activating factor (BAFF) has a role in the maturation and maintenance of B cells and is associated with rheumatoid arthritis (RA). Here, we investigated whether tumor necrosis factor (TNF)-α-induced BAFF expression controls the survival of fibroblast-like synoviocytes (FLS) and whether their survival can be regulated by TNF-α-mediated upregulation of hypoxia-inducible factor (HIF)-1α using MH7A synovial cells transfected with the SV40 T antigen. More TNF-α-treated cells died compared with the control. Survival was increased by incubation with Z-VAD but inhibited after transfection with BAFF-siRNA. Both BAFF and HIF-1α expression were enhanced when MH7A cells were treated with TNF-α. TNF-α-induced BAFF expression decreased in response to HIF-1α-siRNA, whereas it increased under hypoxia or by overexpressing HIF-1α. The HIF-1α binding site on the BAFF promoter (-693 to -688 bp) was confirmed by chromatin immunoprecipitation assay to detect the -750 to -501 bp and -800 to -601 bp regions. The BAFF promoter increased in response to TNF-α treatment or overexpression of HIF-1α. However, TNF-α-induced BAFF expression and promoter activity decreased after treatment with the ERK inhibitor PD98059. Cell death was enhanced by PD98059 but was inhibited by overexpression of HIF-1α. Taken together, our results demonstrate that BAFF expression to control synovial cell survival was regulated by HIF-1α binding to the BAFF promoter, and suggest for the first time that HIF-1α might be involved in the production of inflammatory cytokines to regulate the physiological function of rheumatic FLS.

  11. Elevated serum levels of APRIL, but not BAFF, in patients with atopic dermatitis.

    PubMed

    Matsushita, Takashi; Fujimoto, Manabu; Echigo, Takeshi; Matsushita, Yukiyo; Shimada, Yuka; Hasegawa, Minoru; Takehara, Kazuhiko; Sato, Shinichi

    2008-03-01

    Elevated serum levels of B-cell-activating factor belonging to the tumor necrosis factor family (BAFF) and/or a proliferation-inducing ligand (APRIL) are shown in autoimmune diseases. We determined serum levels of BAFF and APRIL, and clinical association in patients with atopic dermatitis (AD). Serum levels of BAFF and APRIL from 35 patients with AD, 25 patients with psoriasis vulgaris, 25 patients with systemic lupus erythematosus and 25 normal healthy subjects were examined by enzyme-linked immunosorbent assay. Serum levels of APRIL, but not BAFF, were significantly elevated in patients with AD than in healthy controls or patients with psoriasis vulgaris. Patients with severe AD exhibited significantly increased APRIL levels compared to patients with moderate AD and mild AD, and serum APRIL levels were significantly decreased after treatment compared with those before treatment. In addition, increased APRIL levels were significantly associated with serum immunoglobulin E levels and blood eosinophil numbers. These results suggest that elevated serum levels of APRIL are associated with disease severity and activity in AD, and APRIL may have an important role in the pathogenesis of AD.

  12. Increased Interleukin-17 and decreased BAFF serum levels in drug-free acute schizophrenia.

    PubMed

    El Kissi, Yousri; Samoud, Samar; Mtiraoui, Ahlem; Letaief, Leila; Hannachi, Neila; Ayachi, Mouna; Ali, Bechir Ben Hadj; Boukadida, Jalel

    2015-01-30

    Hypotheses regarding an immune-cytokine basis of schizophrenia have been postulated with controversial findings and a lack of data related to many cytokines. The aim of this study was to assess serum levels of Interferon-γ (IFN-γ), Interleukin-4 (IL-4), Transforming Growth Factor-β (TGF-β), Interleukin-17 (IL-17) and B-cell Activating Factor (BAFF) in schizophrenic patients and to determine correlations between cytokine levels and clinical parameters. Serum cytokine levels were measured with ELISA techniques in 60 neuroleptic-free patients on acute phase of the disease (BPRS≥40) and 28 healthy controls matched for age and sex. Current symptoms were assessed with Brief Psychiatric Rating Scale (BPRS), Positive and Negative Syndrome Scale (PANSS), Scale for the Assessment of Positive Symptoms (SAPS) and Scale for the Assessment of Negative Symptoms (SANS). No significant difference was found between patients and controls regarding IFN-γ serum levels. IL-4 was not detected in both groups. Patients exhibited significantly higher IL-17 and lower BAFF serum levels. IL-17 and BAFF levels were negatively correlated in schizophrenic patients. SANS global score was negatively correlated with IL-17 and positively correlated with IFN-γ serum levels. These results argue against the involvement of Th1 or Th2 population cells in schizophrenia. IL-17 and BAFF could be valuable markers for schizophrenia.

  13. Adipocytes as immune cells: differential expression of TWEAK, BAFF, and APRIL and their receptors (Fn14, BAFF-R, TACI, and BCMA) at different stages of normal and pathological adipose tissue development.

    PubMed

    Alexaki, Vassilia-Ismini; Notas, George; Pelekanou, Vassiliki; Kampa, Marilena; Valkanou, Maria; Theodoropoulos, Panayiotis; Stathopoulos, Efstathios N; Tsapis, Andreas; Castanas, Elias

    2009-11-01

    Adipose tissue represents a rich source of multipotent stem cells. Mesenchymal cells, isolated from this source, can differentiate to other cell types in vitro and therefore can be used for a number of regenerative therapies. Our view of adipose tissue has recently changed, establishing adipocytes as new members of the immune system, as they produce a number of proinflammatory cytokines (such as IL-6 and TNFalpha and chemokines, in addition to adipokines (leptin, adiponectin, resistin) and molecules associated with the innate immune system. In this paper, we report the differential expression of TNF-superfamily members B cell activating factor of the TNF Family (BAFF), a proliferation inducing ligand (APRIL), and TNF-like weak inducer of apoptosis (TWEAK) in immature-appearing and mature adipocytes and in benign and malignant adipose tissue-derived tumors. These ligands act through their cognitive receptors, BAFF receptor, transmembrane activator and calcium signal-modulating cyclophilic ligand (TACI), B cell maturation Ag (BCMA), and fibroblast growth factor-inducible 14 (Fn14), which are also expressed in these cells. We further report the existence of functional BCMA, TACI, and Fn14 receptors and their ligands BAFF, APRIL, and TWEAK on adipose tissue-derived mesenchymal cells, their interaction modifying the rate of adipogenesis. Our data integrate BAFF, APRIL, and TWEAK and their receptors BCMA, TACI, and Fn14 as novel potential mediators of adipogenesis, in addition to their specific role in immunity, and define immature and mature adipocytes as source of immune mediators.

  14. Characterization of BAFF and APRIL subfamily receptors in rainbow trout (Oncorhynchus mykiss). Potential role of the BAFF / APRIL axis in the pathogenesis of proliferative kidney disease

    PubMed Central

    Granja, Aitor G.; Holland, Jason W.; Pignatelli, Jaime; Secombes, Christopher J.; Tafalla, Carolina

    2017-01-01

    Proliferative kidney disease (PKD) is a parasitic infection of salmonid fish characterized by hyper-secretion of immunoglobulins in response to the presence of the myxozoan parasite, Tetracapsuloides bryosalmonae. In this context, we hypothesized that the BAFF/APRIL axis, known to play a major role in B cell differentiation and survival in mammals, could be affected by the parasite and consequently be involved in the apparent shift in normal B cell activity. To regulate B cell activity, BAFF and APRIL bind to transmembrane activator and calcium modulator and cyclophilin ligand interactor (TACI) and B cell maturation antigen (BCMA), whereas BAFF also binds to BAFF receptor (BAFF-R). In teleost fish, although some BAFF and APRIL sequences have been reported, their receptors have not been identified. Thus, as a first step in the current work, we have identified homologues to mammalian TACI, BCMA and BAFF-R in rainbow trout (Oncorhynchus mykiss), that constitute the first report of BAFF and APRIL receptor sequences in fish. Subsequently we studied the transcriptional modulation of BAFF, APRIL, and the fish-specific related cytokine, BALM and their putative receptors in fish naturally exposed to T. bryosalmonae. Finally, to gain further insights on the functional role that these cytokines play during the course of PKD, we have studied their effect on the survival of kidney IgM+ B cells and on immunoglobulin transcription. Our results support the premise that the BAFF / APRIL axis could play an important role during PKD, which may open the possibility of new therapeutic treatments against the disease. PMID:28323891

  15. Rapamycin inhibits BAFF-stimulated cell proliferation and survival by suppressing mTOR-mediated PP2A-Erk1/2 signaling pathway in normal and neoplastic B-lymphoid cells.

    PubMed

    Zeng, Qingyu; Zhang, Hai; Qin, Jiamin; Xu, Zhigang; Gui, Lin; Liu, Beibei; Liu, Chunxiao; Xu, Chong; Liu, Wen; Zhang, Shuangquan; Huang, Shile; Chen, Long

    2015-12-01

    B-cell activating factor (BAFF) is involved in not only physiology of normal B cells, but also pathophysiology of aggressive B cells related to malignant and autoimmune diseases. Rapamycin, a lipophilic macrolide antibiotic, has recently shown to be effective in the treatment of human lupus erythematosus. However, how rapamycin inhibits BAFF-stimulated B-cell proliferation and survival has not been fully elucidated. Here, we show that rapamycin inhibited human soluble BAFF (hsBAFF)-induced cell proliferation and survival in normal and B-lymphoid (Raji and Daudi) cells by activation of PP2A and inactivation of Erk1/2. Pretreatment with PD98059, down-regulation of Erk1/2, expression of dominant negative MKK1, or overexpression of wild-type PP2A potentiated rapamycin's suppression of hsBAFF-activated Erk1/2 and B-cell proliferation/viability, whereas expression of constitutively active MKK1, inhibition of PP2A by okadaic acid, or expression of dominant negative PP2A attenuated the inhibitory effects of rapamycin. Furthermore, expression of a rapamycin-resistant and kinase-active mTOR (mTOR-T), but not a rapamycin-resistant and kinase-dead mTOR-T (mTOR-TE), conferred resistance to rapamycin's effects on PP2A, Erk1/2 and B-cell proliferation/viability, implying mTOR-dependent mechanism involved. The findings indicate that rapamycin inhibits BAFF-stimulated cell proliferation/survival by targeting mTOR-mediated PP2A-Erk1/2 signaling pathway in normal and neoplastic B-lymphoid cells. Our data highlight that rapamycin may be exploited for preventing excessive BAFF-induced aggressive B-cell malignancies and autoimmune diseases.

  16. Neutralization of (NK-cell-derived) B-cell activating factor by Belimumab restores sensitivity of chronic lymphoid leukemia cells to direct and Rituximab-induced NK lysis.

    PubMed

    Wild, J; Schmiedel, B J; Maurer, A; Raab, S; Prokop, L; Stevanović, S; Dörfel, D; Schneider, P; Salih, H R

    2015-08-01

    Natural killer (NK) cells are cytotoxic lymphocytes that substantially contribute to the therapeutic benefit of antitumor antibodies like Rituximab, a crucial component in the treatment of B-cell malignancies. In chronic lymphocytic leukemia (CLL), the ability of NK cells to lyse the malignant cells and to mediate antibody-dependent cellular cytotoxicity upon Fc receptor stimulation is compromised, but the underlying mechanisms are largely unclear. We report here that NK-cells activation-dependently produce the tumor necrosis factor family member 'B-cell activating factor' (BAFF) in soluble form with no detectable surface expression, also in response to Fc receptor triggering by therapeutic CD20-antibodies. BAFF in turn enhanced the metabolic activity of primary CLL cells and impaired direct and Rituximab-induced lysis of CLL cells without affecting NK reactivity per se. The neutralizing BAFF antibody Belimumab, which is approved for treatment of systemic lupus erythematosus, prevented the effects of BAFF on the metabolism of CLL cells and restored their susceptibility to direct and Rituximab-induced NK-cell killing in allogeneic and autologous experimental systems. Our findings unravel the involvement of BAFF in the resistance of CLL cells to NK-cell antitumor immunity and Rituximab treatment and point to a benefit of combinatory approaches employing BAFF-neutralizing drugs in B-cell malignancies.

  17. B Cell-Activating Factor Regulates Different Aspects of B Cell Functionality and Is Produced by a Subset of Splenic B Cells in Teleost Fish

    PubMed Central

    Tafalla, Carolina; González, Lucia; Castro, Rosario; Granja, Aitor G.

    2017-01-01

    In mammals, B cell functionality is greatly influenced by cytokines released by innate cells, such as macrophages or dendritic cells, upon the early recognition of common pathogen patterns through invariant receptors. B cell-activating factor (BAFF) is one of these innate B cell-helper signals and plays a key role in the survival and differentiation of B cells. Although, evolutionarily, teleost fish constitute the first animal group in which adaptive immunity based on Ig receptors is present, fish still rely greatly on innate responses. In this context, we hypothesized that BAFF would play a key role in the control of B cell responses in fish. Supporting this, our results show that teleost BAFF recapitulates mammalian BAFF stimulating actions on B cells, upregulating the expression of membrane MHC II, improving the survival of fish naïve B cells and antibody-secreting cells, and increasing the secretion of IgM. Surprisingly, we also demonstrate that BAFF is not only produced in fish by myeloid cells but is also produced by a subset of splenic B cells. Thus, if this B cell-produced BAFF proves to be actively regulating this same B cell subset, our findings point to an ancient mechanism to control B cell differentiation and survival in lower vertebrates, which has been silenced in mammals in physiological conditions, but reemerges under pathological conditions, such as B cell lymphomas and autoimmune diseases. PMID:28360916

  18. Crosstalk between signals initiated from TLR4 and cell surface BAFF results in synergistic induction of proinflammatory mediators in THP-1 cells

    PubMed Central

    Lim, Su-Geun; Kim, Jae-Kwan; Suk, Kyoungho; Lee, Won-Ha

    2017-01-01

    Cellular response to stimulation is mediated by meshwork of signaling pathways that may share common signaling adaptors. Here, we present data demonstrating that signaling pathways initiated from the membrane-bound form of B-cell activating factor (BAFF) can crosstalk with lipopolysaccharide (LPS)-induced signaling for synergistic expression of proinflammatory mediators in the human macrophage-like cell line THP-1. Co-treatment of the cells with BAFF-specific monoclonal antibody and LPS resulted in enhanced mitogen-activated protein kinase (MAPK)/mitogen- and stress-activated protein kinase (MSK)-mediated phosphorylation of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) p65 subunit (Ser276), which then interacts with CREB binding protein (CBP) for subsequent acetylation. Simultaneously, the phosphorylation of cyclic AMP-response element binding protein (CREB) was enhanced through the combined action of phosphatidylinositol-3-kinase (PI3K)/AKT and MAPK/MSK pathways, and the resulting phospho-CREB interacted with the NF-κB/CBP complex. Transfection of CREB-specific siRNA inhibited the BAFF-mediated enhancing effect indicating that the formation of the CREB/NF-κB/CBP complex is required for the synergistic induction of the proinflammatory genes. These findings indicate that BAFF-mediated reverse signaling can modulate LPS-induced inflammatory activation through regulation of NF-κB and CREB activity and point out the necessity to re-evaluate the role of BAFF in diseases where its expression is high in macrophages. PMID:28374824

  19. Porcine B-cell activating factor promotes anti-FMDV antibodies in vitro but not in vivo after DNA vaccination of pigs.

    PubMed

    Bergamin, Fabio; Saurer, Leslie; Neuhaus, Viviane; McCullough, Kenneth C; Summerfield, Artur

    2007-12-15

    'B-cell activating factor belonging to the TNF family' (BAFF) represents a cytokine produced by antigen presenting cells promoting B-cell maturation, activation and immunoglobulin class switching. In the present study, we demonstrate expression of BAFF on cultured monocyte-derived dendritic cells, which is further enhanced by interferon-alpha or interferon-gamma treatment. From these cells, porcine BAFF was cloned and the recombinant protein was expressed in mammalian cells with and without a FLAG tag at the carboxyl terminus. Only the protein without the FLAG tag was bioactive in vitro, and promoted B-cell survival and the differentiation of foot-and-mouth disease virus (FMDV)-specific memory B cells into antibody producing cells. Based on this result it was tested whether BAFF can enhance FMDV antibody responses in the context of a DNA vaccination. To this end, pigs were immunised with the anti-FMDV DNA vaccine plasmid pcDNA3.1/P1-2A3C3D and a pCI plasmid expressing porcine BAFF. Using a needle-free transdermal application method, also referred to as 'jet injection', pigs were vaccinated three times and their humoral response quantified by ELISA and a virus neutralisation test. After the third vaccination, three out of six animals vaccinated with the pcDNA3.1/P1-2A3C3D alone but none of the animals that also received the BAFF expressing plasmid had seroconverted. These data suggest that BAFF is not appropriate as a genetic adjuvant when applied as a simple co-injection with the antigen-encoding plasmid.

  20. The Expression of BAFF, APRIL and TWEAK Is Altered in Eczema Skin but Not in the Circulation of Atopic and Seborrheic Eczema Patients

    PubMed Central

    Chen, Yunying; Lind Enoksson, Sara; Johansson, Catharina; Karlsson, Maria A.; Lundeberg, Lena; Nilsson, Gunnar

    2011-01-01

    The TNF family cytokines BAFF (B-cell activating factor of the TNF family) and APRIL (a proliferation-inducing ligand) are crucial survival factors for B-cell development and activation. B-cell directed treatments have been shown to improve atopic eczema (AE), suggesting the involvement of these cytokines in the pathogenesis of AE. We therefore analyzed the expression of these TNF cytokines in AE, seborrheic eczema (SE) and healthy controls (HC). The serum/plasma concentration of BAFF, APRIL and a close TNF member TWEAK (TNF-like weak inducer of apoptosis) was measured by ELISA. The expression of these cytokines and their receptors in skin was analyzed by quantitative RT-PCR and immunofluorescence. Unlike other inflammatory diseases including autoimmune diseases and asthma, the circulating levels of BAFF, APRIL and TWEAK were not elevated in AE or SE patients compared with HCs and did not correlate with the disease severity or systemic IgE levels in AE patients. Interestingly, we found that the expression of these cytokines and their receptors was altered in positive atopy patch test reactions in AE patients (APT-AE) and in lesional skin of AE and SE patients. The expression of APRIL was decreased and the expression of BAFF was increased in eczema skin of AE and SE, which could contribute to a reduced negative regulatory input on B-cells. This was found to be more pronounced in APT-AE, the initiating acute stage of AE, which may result in dysregulation of over-activated B-cells. Furthermore, the expression levels of TWEAK and its receptor positively correlated to each other in SE lesions, but inversely correlated in AE lesions. These results shed light on potential pathogenic roles of these TNF factors in AE and SE, and pinpoint a potential of tailored treatments towards these factors in AE and SE. PMID:21765951

  1. NIK overexpression amplifies, whereas ablation of its TRAF3-binding domain replaces BAFF:BAFF-R-mediated survival signals in B cells.

    PubMed

    Sasaki, Yoshiteru; Calado, Dinis P; Derudder, Emmanuel; Zhang, Baochun; Shimizu, Yuri; Mackay, Fabienne; Nishikawa, Shin-ichi; Rajewsky, Klaus; Schmidt-Supprian, Marc

    2008-08-05

    BAFF-R-dependent activation of the alternative NF-kappaB pathway plays an essential role in mature B cell survival. Mutations leading to overexpression of NIK and deletion of the TRAF3 gene are implicated in human multiple myeloma. We show that overexpression of NIK in mouse B lymphocytes amplifies alternative NF-kappaB activation and peripheral B cell numbers in a BAFF-R-dependent manner, whereas uncoupling NIK from TRAF3-mediated control causes maximal p100 processing and dramatic hyperplasia of BAFF-R-independent B cells. NIK controls alternative NF-kappaB signaling by increasing the protein levels of its negative regulator TRAF3 in a dose-dependent fashion. This mechanism keeps NIK protein levels below detection even when they cause B cell hyperplasia, so that contributions of NIK to B cell pathologies can easily be overlooked.

  2. IgG-Immune Complexes Promote B Cell Memory by Inducing BAFF.

    PubMed

    Kang, SunAh; Keener, Amanda B; Jones, Shannon Z; Benschop, Robert J; Caro-Maldonado, Alfredo; Rathmell, Jeffrey C; Clarke, Stephen H; Matsushima, Glenn K; Whitmire, Jason K; Vilen, Barbara J

    2016-01-01

    Memory B cell responses are vital for protection against infections but must also be regulated to prevent autoimmunity. Cognate T cell help, somatic hypermutation, and affinity maturation within germinal centers (GCs) are required for high-affinity memory B cell formation; however, the signals that commit GC B cells to the memory pool remain unclear. In this study, we identify a role for IgG-immune complexes (ICs), FcγRs, and BAFF during the formation of memory B cells in mice. We found that early secretion of IgG in response to immunization with a T-dependent Ag leads to IC-FcγR interactions that induce dendritic cells to secrete BAFF, which acts at or upstream of Bcl-6 in activated B cells. Loss of CD16, hematopoietic cell-derived BAFF, or blocking IC:FcγR regions in vivo diminished the expression of Bcl-6, the frequency of GC and memory B cells, and secondary Ab responses. BAFF also contributed to the maintenance and/or expansion of the follicular helper T cell population, although it was dispensable for their formation. Thus, early Ab responses contribute to the optimal formation of B cell memory through IgG-ICs and BAFF. Our work defines a new role for FcγRs in GC and memory B cell responses.

  3. Vibration Induces BAFF Overexpression and Aberrant O-Glycosylation of IgA1 in Cultured Human Tonsillar Mononuclear Cells in IgA Nephropathy

    PubMed Central

    Ye, Muyao; Liu, Chan; Yan, Wenzhe; Peng, Xiaofei; He, Liyu; Liu, Hong; Liu, Fuyou

    2016-01-01

    Objective. To investigate the influence of in vitro vibratory stimulation of human tonsillar mononuclear cells (TMCs). Methods. Fourteen IgA nephropathy (IgAN) patients with chronic tonsillitis (CT) and 12 CT patients with no renal pathology were enrolled. Group A TMCs were collected after 24 hours of culture and used to determine baseline levels. TMCs in groups B, C, D, E, and F were exposed to vibratory stimulation (60 Hz) for 0 (as the control group), 1, 3, 5, and 10 minutes, respectively. Results. Baseline concentrations of B-cell-activation factor (BAFF) and IgA1, BAFF mRNA expression, and aberrant O-glycosylation IgA1 level were higher in the IgAN group as compared to that in the CT group, and all increased after vibratory stimulation. Baseline mRNA expressions of core β1,3-galactosyltransferase (C1GALT1) and core β1,3GalT-specific molecular chaperone (Cosmc) were lower in the IgAN group; the levels decreased further after vibratory stimulation. Conclusion. In patients with IgAN, vibratory stimulation of TMCs appears to induce IgA1 secretion through activation of BAFF release and to aberrant O-glycosylation IgA1 by suppressing C1GALT1 and Cosmc expression. In vitro vibratory stimulation of human TMCs mimics the vibratory simulation of palatine tonsils produced by vocal cords during phonation. PMID:27672662

  4. MiR-30a-3p Negatively Regulates BAFF Synthesis in Systemic Sclerosis and Rheumatoid Arthritis Fibroblasts

    PubMed Central

    Philippe, Lucas; Gong, Ya-Zhuo; Bahram, Seiamak; Cetin, Semih; Pfeffer, Sébastien; Gottenberg, Jacques-Eric; Wachsmann, Dominique; Georgel, Philippe; Sibilia, Jean

    2014-01-01

    We evaluated micro (mi) RNA-mediated regulation of BAFF expression in fibroblasts using two concomitant models: (i) synovial fibroblasts (FLS) isolated from healthy controls (N) or Rheumatoid Arthritis (RA) patients; (ii) human dermal fibroblasts (HDF) isolated from healthy controls (N) or Systemic Sclerosis (SSc) patients. Using RT-qPCR and ELISA, we first showed that SScHDF synthesized and released BAFF in response to Poly(I:C) or IFN-γ treatment, as previously observed in RAFLS, whereas NHDF released BAFF preferentially in response to IFN-γ. Next, we demonstrated that miR-30a-3p expression was down regulated in RAFLS and SScHDF stimulated with Poly(I:C) or IFN-γ. Moreover, we demonstrated that transfecting miR-30a-3p mimic in Poly(I:C)- and IFN-γ-activated RAFLS and SScHDF showed a strong decrease on BAFF synthesis and release and thus B cells survival in our model. Interestingly, FLS and HDF isolated from healthy subjects express higher levels of miR-30a-3p and lower levels of BAFF than RAFLS and SScHDF. Transfection of miR-30a-3p antisense in Poly(I:C)- and IFN-γ-activated NFLS and NHDF upregulated BAFF secretion, confirming that this microRNA is a basal repressors of BAFF expression in cells from healthy donors. Our data suggest a critical role of miR-30a-3p in the regulation of BAFF expression, which could have a major impact in the regulation of the autoimmune responses occurring in RA and SSc. PMID:25360821

  5. Characterisation of the TNF superfamily members CD40L and BAFF in the small-spotted catshark (Scyliorhinus canicula).

    PubMed

    Li, Ronggai; Redmond, Anthony K; Wang, Tiehui; Bird, Steve; Dooley, Helen; Secombes, Chris J

    2015-11-01

    The tumour necrosis factor superfamily (TNFSF) members CD40L and BAFF play critical roles in mammalian B cell survival, proliferation and maturation, however little is known about these key cytokines in the oldest jawed vertebrates, the cartilaginous fishes. Here we report the cloning of CD40L and BAFF orthologues (designated ScCD40L and ScBAFF) in the small-spotted catshark (Scyliorhinus canicula). As predicted both proteins are type II membrane-bound proteins with a TNF homology domain in their extracellular region and both are highly expressed in shark immune tissues. ScCD40L transcript levels correlate with those of TCRα and transcription of both genes is modulated in peripheral blood leukocytes following in vitro stimulation. Although a putative CD40L orthologue was identified in the elephant shark genome the work herein is the first molecular characterisation and transcriptional analysis of CD40L in a cartilaginous fish. ScBAFF was also cloned and its transcription characterised in an attempt to resolve the discrepancies observed between spiny dogfish BAFF and bamboo shark BAFF in previously published studies.

  6. Prognostic significance of ligands belonging to tumour necrosis factor superfamily in acute lymphoblastic leukaemia.

    PubMed

    Bolkun, L; Lemancewicz, D; Jablonska, E; Szumowska, A; Bolkun-Skornicka, U; Moniuszko, M; Dzieciol, J; Kloczko, J

    2015-03-01

    Altered activities of ligands belonging to tumour necrosis factor (TNF) superfamily, namely B-cell activating factor (BAFF), a proliferation-inducing ligand (APRIL) and apoptosis inducing ligand (TRAIL) were demonstrated in several haematological diseases including acute lymphoblastic leukaemia (ALL). BAFF, APRIL and TRAIL provide crucial survival signals to immature, naive and activated B cells. These ligands are capable of activating a broad spectrum of intracellular signalling cascades that can either induce apoptosis or protect from programmed cell death. BAFF and APRIL, which can directly activate the NF-κB pathway, have been identified as crucial survival factors for ALL cells. Here, we have analyzed serum BAFF, APRIL and TRAIL concentrations in 48 patients with newly diagnosed ALL and 44 healthy volunteers. The levels of APRIL and BAFF were significantly higher in ALL patients as compared to healthy volunteers. In contrast, concentrations of TRAIL were significantly lower in ALL patients. Moreover, following induction, the levels of APRIL, but not BAFF or TRAIL, were significantly lower in a group of patients with complete remission (CR) as compared to non-respondent (NR) ALL patients. Furthermore, we demonstrated statistically significant differences in concentrations of APRIL between CR MRD-negative and CR, MRD-positive ALL patients. Notably detection of higher concentrations of APRIL was associated with shorter leukaemia-free survival and overall survival. Altogether, our data indicate that APRIL can play an important role in the pathogenesis of ALL and the measurement of APRIL levels can improve prognostication in ALL patients.

  7. Antigen-affinity controls pre-germinal centser B cell selection by promoting Mcl-1 induction through BAFF receptor signaling

    PubMed Central

    Wensveen, Felix M.; Slinger, Erik; van Attekum, Martijn HA; Brink, Robert; Eldering, Eric

    2016-01-01

    Upon antigen encounter, the responsive B cell pool undergoes stringent selection which eliminates cells with low B cell receptor (BCR) affinity. Already before formation of the germinal center, activated B cells of low-affinity are negatively selected in a process that is molecularly not well understood. In this study, we investigated the mechanism behind pre-GC affinity-mediated B cell selection. We applied affinity mutants of HEL antigen and found that rapidly after activation B cells become highly dependent on the cytokine BAFF. Moreover, expression of BAFF receptor CD268 is regulated in a BCR-affinity dependent fashion. High affinity responses via BAFF correlated with PI3K activation, which controlled expression of the pro-survival protein Mcl-1, and thereby increased survival. In the presence of excess BAFF, or in absence of the Mcl-1 antagonist Noxa, more low-affinity B cells survived the first two days after antigen encounter. This resulted in increased numbers of antigen-specific B cells of low affinity upon immunization and reduced the overall affinity of cells that contributed to the germinal center reaction. Our findings elucidate a crucial molecular pathway of B cell selection in the earliest phases of activation by identifying a novel link between BCR affinity and BAFF-R signaling towards Mcl-1. PMID:27762293

  8. The B-cell-activating factor signalling pathway is associated with Helicobacter pylori independence in gastric mucosa-associated lymphoid tissue lymphoma without t(11;18)(q21;q21).

    PubMed

    Kuo, Sung-Hsin; Tsai, Hui-Jen; Lin, Chung-Wu; Yeh, Kun-Huei; Lee, Hsiao-Wei; Wei, Ming-Feng; Shun, Chia-Tung; Wu, Ming-Shiang; Hsu, Ping-Ning; Chen, Li-Tzong; Cheng, Ann-Lii

    2017-02-01

    We previously reported that activation of the B-cell-activating factor (BAFF) pathway upregulates nuclear factor-κB (NF-κB) and induces BCL3 and BCL10 nuclear translocation in Helicobacter pylori (HP)-independent gastric diffuse large B-cell lymphoma (DLBCL) tumours with evidence of mucosa-associated lymphoid tissue (MALT). However, the significance of BAFF expression in HP independence of gastric low-grade MALT lymphomas without t(11;18)(q21;q21) remains unexplored. Sixty-four patients who underwent successful HP eradication for localized HP-positive gastric MALT lymphomas without t(11;18)(q21;q21) were studied. BAFF expression was significantly higher in the HP-independent group than in the HP-dependent group [22/26 (84.6%) versus 8/38 (21.1%); p < 0.001]. Similarly, BAFF receptor (BAFF-R) expression (p = 0.004) and nuclear BCL3 (p = 0.004), BCL10 (p < 0.001), NF-κB (p65) (p = 0.001) and NF-κB (p52) (p = 0.005) expression were closely correlated with the HP independence of these tumours. Moreover, BAFF overexpression was significantly associated with BAFF-R expression and nuclear BCL3, BCL10, NF-κB (p65) and NF-κB (p52) expression. These findings were further validated in an independent cohort, including 40 HP-dependent cases and 18 HP-independent cases of gastric MALT lymphoma without t(11;18)(q21;q21). The biological significance of BAFF signalling in t(11;18)(q21;q21)-negative lymphoma cells was further studied in two types of lymphoma B cell: OCI-Ly3 [non-germinal centre B-cell origin DLBCL without t(11;18)(q21;q21) cell line] and MA-1 [t(14;18)(q32;q21)/IGH-MALT1-positive DLBCL cell line]. In both cell lines, we found that BAFF activated the canonical NF-κB and AKT pathways, and induced the formation of BCL10-BCL3 complexes, which translocated to the nucleus. BCL10 and BCL3 nuclear translocation and NF-κB (p65) transactivation were inhibited by either LY294002 or by silencing BCL3 or BCL10 with small interfering RNA. BAFF also

  9. B-cell survival factors in autoimmune rheumatic disorders

    PubMed Central

    Morais, Sandra A.; Vilas-Boas, Andreia

    2015-01-01

    Autoimmune rheumatic disorders have complex etiopathogenetic mechanisms in which B cells play a central role. The importance of factors stimulating B cells, notably the B-cell activating factor (BAFF) and A proliferation inducing ligand (APRIL) axis is now recognized. BAFF and APRIL are cytokines essential for B-cell proliferation and survival from the immature stages to the development of plasma cells. Their levels are increased in some subsets of patients with autoimmune disorders. Several recent biologic drugs have been developed to block this axis, namely belimumab [already licensed for systemic lupus erythematosus (SLE) treatment], tabalumab, atacicept and blisibimod. Many clinical trials to evaluate the safety and efficacy of these drugs in several autoimmune disorders are ongoing, or have been completed recently. This review updates the information on the use of biologic agents blocking BAFF/APRIL for patients with SLE, rheumatoid arthritis, Sjögren’s syndrome and myositis. PMID:26288664

  10. Ectopic germinal centers, BAFF and anti-B-cell therapy in myasthenia gravis.

    PubMed

    Berrih-Aknin, Sonia; Ragheb, Samia; Le Panse, Rozen; Lisak, Robert P

    2013-07-01

    Myasthenia gravis (MG) is an autoimmune disease mediated by antibodies directed to molecules of the endplate of the neuromuscular junction. B cells play a major role in MG disease since they produce the pathogenic antibodies and therapies targeting B cells are effective. The aim of this article was to review the role of B cells in myasthenia gravis. We will first describe what we know about B cells in this disease and examine the involvement of the B cells in the thymus of MG patients. We will detail the role of factors associated with B-cell function such as BAFF. Finally, we will discuss the effects of therapy targeting B cells.

  11. Role of BAFF in Opsoclonus-Myoclonus syndrome, a bridge between cancer and autoimmunity.

    PubMed

    Raffaghello, Lizzia; Fuhlhuber, Verena; Bianchi, Giovanna; Conte, Massimo; Blaes, Franz; Gambini, Claudio; Pistoia, Vito

    2013-07-01

    OMS is a rare paraneoplastic disorder that affects adults and children. Pediatric OMS is often associated with NB, a common, solid tumor of childhood, derived from the sympathetic nervous system. The detection of autoantibodies and lymphocytic infiltration in NB patients led to advance an autoimmune hypothesis for the pathogenesis of OMS-related NB. BAFF is a potent modulator of B cell growth and survival upon interaction with its receptors BAFF-R and BCMA. The aim of this study was to investigate mechanism(s) involved in ectopic lymphoid neogenesis in OMS-associated NB. We investigated BAFF, BAFF-R, and BCMA expression in NB tumors associated or not with OMS. Furthermore, we evaluated BAFF expression and secretion in NB cell lines, treated or untreated with differentiating agents. Immunohistochemically, lymphocytes infiltrating NB tumors from patients, with or without OMS, expressed BAFF, BAFF-R, and BCMA, whereas neuroblasts expressed BAFF and BCMA but not BAFF-R. By flow cytometry, BAFF was found to be consistently expressed in NB cell lines. Similarly to the results obtained in tissue lesions, BCMA but not BAFF-R was detected on the surface of all NB cell lines under basal conditions. De novo synthesis of BAFF-R and up-regulation of BCMA were observed in NB cell lines upon treatment with IFN-γ or 13-cis retinoic acid. This study provides new insights in the mechanisms driving the neogenesis of lymphoid follicles and in the functional interactions between tumor and immune cells in OMS-associated NB.

  12. Serum BAFF and APRIL Levels, T-Lymphocyte Subsets, and Immunoglobulins after B-Cell Depletion Using the Monoclonal Anti-CD20 Antibody Rituximab in Myalgic Encephalopathy/Chronic Fatigue Syndrome

    PubMed Central

    Lunde, Sigrid; Kristoffersen, Einar K.; Sapkota, Dipak; Risa, Kristin; Dahl, Olav; Bruland, Ove; Mella, Olav; Fluge, Øystein

    2016-01-01

    Myalgic Encephalopathy/Chronic Fatigue Syndrome (ME/CFS) is a disease of unknown etiology. We have previously suggested clinical benefit from B-cell depletion using the monoclonal anti-CD20 antibody rituximab in a randomized and placebo-controlled study. Prolonged responses were then demonstrated in an open-label phase-II study with maintenance rituximab treatment. Using blood samples from patients in the previous two clinical trials, we investigated quantitative changes in T-lymphocyte subsets, in immunoglobulins, and in serum levels of two B-cell regulating cytokines during follow-up. B-lymphocyte activating factor of the tumor necrosis family (BAFF) in baseline serum samples was elevated in 70 ME/CFS patients as compared to 56 healthy controls (p = 0.011). There were no significant differences in baseline serum BAFF levels between patients with mild, moderate, or severe ME/CFS, or between responders and non-responders to rituximab. A proliferation-inducing ligand (APRIL) serum levels were not significantly different in ME/CFS patients compared to healthy controls at baseline, and no changes in serum levels were seen during follow-up. Immunophenotyping of peripheral blood T-lymphocyte subsets and T-cell activation markers at multiple time points during follow-up showed no significant differences over time, between rituximab and placebo groups, or between responders and non-responders to rituximab. Baseline serum IgG levels were significantly lower in patients with subsequent response after rituximab therapy compared to non-responders (p = 0.03). In the maintenance study, slight but significant reductions in mean serum immunoglobulin levels were observed at 24 months compared to baseline; IgG 10.6–9.5 g/L, IgA 1.8–1.5 g/L, and IgM 0.97–0.70 g/L. Although no functional assays were performed, the lack of significant associations of T- and NK-cell subset numbers with B-cell depletion, as well as the lack of associations to clinical responses, suggest that B

  13. The protein tyrosine phosphatase PTP1B is a negative regulator of CD40 and BAFF-R signaling and controls B cell autoimmunity

    PubMed Central

    Hobeika, Elias; Biesen, Robert; Kollert, Florian; Taddeo, Adriano; Voll, Reinhard E.; Hiepe, Falk

    2014-01-01

    Tyrosine phosphorylation of signaling molecules that mediate B cell activation in response to various stimuli is tightly regulated by protein tyrosine phosphatases (PTPs). PTP1B is a ubiquitously expressed tyrosine phosphatase with well-characterized functions in metabolic signaling pathways. We show here that PTP1B negatively regulates CD40, B cell activating factor receptor (BAFF-R), and TLR4 signaling in B cells. Specifically, PTP1B counteracts p38 mitogen-activated protein kinase (MAPK) activation by directly dephosphorylating Tyr182 of this kinase. Mice with a B cell–specific PTP1B deficiency show increased T cell–dependent immune responses and elevated total serum IgG. Furthermore, aged animals develop systemic autoimmunity with elevated serum anti-dsDNA, spontaneous germinal centers in the spleen, and deposition of IgG immune complexes and C3 in the kidney. In a clinical setting, we observed that B cells of rheumatoid arthritis patients have significantly reduced PTP1B expression. Our data suggest that PTP1B plays an important role in the control of B cell activation and the maintenance of immunological tolerance. PMID:24590766

  14. In vivo amelioration of endogenous antitumor autoantibodies via low-dose P4N through the LTA4H/activin A/BAFF pathway

    PubMed Central

    Lin, Yu-Ling; Tsai, Nu-Man; Hsieh, Cheng-Hao; Ho, Shu-Yi; Chang, Jung; Wu, Hsin-Yi; Hsu, Ming-Hua; Chang, Chia-Ching; Liao, Kuang-Wen; Jackson, Tiffany L. B.; Mold, David E.; Huang, Ru Chih C.

    2016-01-01

    Cancer progression is associated with the development of antitumor autoantibodies in patients’ sera. Although passive treatment with antitumor antibodies has exhibited remarkable therapeutic efficacy, inhibitory effects on tumor progression by endogenous antitumor autoantibodies (EAAs) have been limited. In this study, we show that P4N, a derivative of the plant lignan nordihydroguaiaretic acid (NDGA), enhanced the production of EAAs and inhibited tumor growth at low noncytotoxic concentrations via its immunoregulatory activity. Intratumoral injection of P4N improved the quantity and quality of EAAs, and passive transfer of P4N-induced EAAs dramatically suppressed lung metastasis formation and prolonged the survival of mice inoculated with metastatic CT26 tumor cells. P4N-induced EAAs specifically recognized two surface antigens, 78-kDa glucose-regulated protein (GRP78) and F1F0 ATP synthase, on the plasma membrane of cancer cells. Additionally, P4N treatment led to B-cell proliferation, differentiation to plasma cells, and high titers of autoantibody production. By serial induction of autocrine and paracrine signals in monocytes, P4N increased B-cell proliferation and antibody production via the leukotriene A4 hydrolase (LTA4H)/activin A/B-cell activating factor (BAFF) pathway. This mechanism provides a useful platform for studying and seeking a novel immunomodulator that can be applied in targeting therapy by improving the quantity and quality of the EAAs. PMID:27856749

  15. In vivo amelioration of endogenous antitumor autoantibodies via low-dose P4N through the LTA4H/activin A/BAFF pathway.

    PubMed

    Lin, Yu-Ling; Tsai, Nu-Man; Hsieh, Cheng-Hao; Ho, Shu-Yi; Chang, Jung; Wu, Hsin-Yi; Hsu, Ming-Hua; Chang, Chia-Ching; Liao, Kuang-Wen; Jackson, Tiffany L B; Mold, David E; Huang, Ru Chih C

    2016-11-29

    Cancer progression is associated with the development of antitumor autoantibodies in patients' sera. Although passive treatment with antitumor antibodies has exhibited remarkable therapeutic efficacy, inhibitory effects on tumor progression by endogenous antitumor autoantibodies (EAAs) have been limited. In this study, we show that P4N, a derivative of the plant lignan nordihydroguaiaretic acid (NDGA), enhanced the production of EAAs and inhibited tumor growth at low noncytotoxic concentrations via its immunoregulatory activity. Intratumoral injection of P4N improved the quantity and quality of EAAs, and passive transfer of P4N-induced EAAs dramatically suppressed lung metastasis formation and prolonged the survival of mice inoculated with metastatic CT26 tumor cells. P4N-induced EAAs specifically recognized two surface antigens, 78-kDa glucose-regulated protein (GRP78) and F1F0 ATP synthase, on the plasma membrane of cancer cells. Additionally, P4N treatment led to B-cell proliferation, differentiation to plasma cells, and high titers of autoantibody production. By serial induction of autocrine and paracrine signals in monocytes, P4N increased B-cell proliferation and antibody production via the leukotriene A4 hydrolase (LTA4H)/activin A/B-cell activating factor (BAFF) pathway. This mechanism provides a useful platform for studying and seeking a novel immunomodulator that can be applied in targeting therapy by improving the quantity and quality of the EAAs.

  16. Factor XII Contact Activation.

    PubMed

    Naudin, Clément; Burillo, Elena; Blankenberg, Stefan; Butler, Lynn; Renné, Thomas

    2017-03-27

    Contact activation is the surface-induced conversion of factor XII (FXII) zymogen to the serine protease FXIIa. Blood-circulating FXII binds to negatively charged surfaces and this contact to surfaces triggers a conformational change in the zymogen inducing autoactivation. Several surfaces that have the capacity for initiating FXII contact activation have been identified, including misfolded protein aggregates, collagen, nucleic acids, and platelet and microbial polyphosphate. Activated FXII initiates the proinflammatory kallikrein-kinin system and the intrinsic coagulation pathway, leading to formation of bradykinin and thrombin, respectively. FXII contact activation is well characterized in vitro and provides the mechanistic basis for the diagnostic clotting assay, activated partial thromboplastin time. However, only in the past decade has the critical role of FXII contact activation in pathological thrombosis been appreciated. While defective FXII contact activation provides thromboprotection, excess activation underlies the swelling disorder hereditary angioedema type III. This review provides an overview of the molecular basis of FXII contact activation and FXII contact activation-associated disease states.

  17. Signaling by the tumor necrosis factor receptor superfamily in B-cell biology and disease.

    PubMed

    Rickert, Robert C; Jellusova, Julia; Miletic, Ana V

    2011-11-01

    Members of the tumor necrosis factor receptor superfamily (TNFRSF) participate prominently in B-cell maturation and function. In particular, B-cell activating factor belonging to the TNF family receptor (BAFF-R), B-cell maturation antigen (BCMA), and transmembrane activator and calcium modulator and cyclophilin ligand interactor (TACI) play critical roles in promoting B-cell survival at distinct stages of development by engaging a proliferation-inducing ligand (APRIL) and/or BAFF. CD40 is also essential for directing the humoral response to T-cell-dependent antigens. Signaling by the TNFRSF is mediated primarily, albeit not exclusively, via the TNFR-associated factor (TRAF) proteins and activation of the canonical and/or non-canonical nuclear factor-κB (NF-κB) pathways. Dysregulated signaling by TNFRSF members can promote B-cell survival and proliferation, causing autoimmunity and neoplasia. In this review, we present a current understanding of the functions of and distinctions between APRIL/BAFF signaling by their respective receptors expressed on particular B-cell subsets. These findings are compared and contrasted with CD40 signaling, which employs similar signaling conduits to achieve distinct cellular outcomes in the context of the germinal center response. We also underscore how new findings and conceptual insights into TNFRSF signaling are facilitating the understanding of B-cell malignancies and autoimmune diseases.

  18. Factors regulating microglia activation

    PubMed Central

    Kierdorf, Katrin; Prinz, Marco

    2013-01-01

    Microglia are resident macrophages of the central nervous system (CNS) that display high functional similarities to other tissue macrophages. However, it is especially important to create and maintain an intact tissue homeostasis to support the neuronal cells, which are very sensitive even to minor changes in their environment. The transition from the “resting” but surveying microglial phenotype to an activated stage is tightly regulated by several intrinsic (e.g., Runx-1, Irf8, and Pu.1) and extrinsic factors (e.g., CD200, CX3CR1, and TREM2). Under physiological conditions, minor changes of those factors are sufficient to cause fatal dysregulation of microglial cell homeostasis and result in severe CNS pathologies. In this review, we discuss recent achievements that gave new insights into mechanisms that ensure microglia quiescence. PMID:23630462

  19. Early BAFF receptor blockade mitigates murine Sjögren's syndrome: Concomitant targeting of CXCL13 and the BAFF receptor prevents salivary hypofunction

    PubMed Central

    Klimatcheva, Ekaterina; Howell, Alan; Fereidouni, Farzad; Levenson, Richard; Rothstein, Thomas L.; Kramer, Jill M.

    2016-01-01

    Sjögren's Syndrome (SS) is a debilitating autoimmune disease. Patients with SS may develop xerostomia. This process is progressive, and there are no therapeutics that target disease etiology. We hypothesized BAFF receptor (BAFFR) blockade would mitigate SS disease development, and neutralization of CXCL13 and BAFF signaling would be more efficacious than BAFFR blockade alone. We treated NOD/ShiLtJ SS mice with soluble BAFF receptor (BAFFR-Fc) or anti-CXCL13/BAFFR-Fc in combination, prior to the development of clinical disease. Our results show treatment with BAFFR-Fc reduced peripheral B cells numbers and decreased sialadenitis. In addition, this treatment reduced total serum immunoglobulin as well as IgG and IgM specific anti-nuclear autoantibodies. NOD/ShiLtJ mice treated with BAFFR-Fc and anti-CXCL13 antibody were protected from salivary deficits. Results from this study suggest blockade of CXCL13 and BAFFR together may be an effective therapeutic strategy in preventing salivary hypofunction and reducing autoantibody titers and sialadenitis in patients with SS. PMID:26826598

  20. Early BAFF receptor blockade mitigates murine Sjögren's syndrome: Concomitant targeting of CXCL13 and the BAFF receptor prevents salivary hypofunction.

    PubMed

    Sharma, Arjun; Kiripolsky, Jeremy; Klimatcheva, Ekaterina; Howell, Alan; Fereidouni, Farzad; Levenson, Richard; Rothstein, Thomas L; Kramer, Jill M

    2016-03-01

    Sjögren's syndrome (SS) is a debilitating autoimmune disease. Patients with SS may develop xerostomia. This process is progressive, and there are no therapeutics that target disease etiology. We hypothesized BAFF receptor (BAFFR) blockade would mitigate SS disease development, and neutralization of CXCL13 and BAFF signaling would be more efficacious than BAFFR blockade alone. We treated NOD/ShiLtJ SS mice with soluble BAFF receptor (BAFFR-Fc) or anti-CXCL13/BAFFR-Fc in combination, prior to the development of clinical disease. Our results show treatment with BAFFR-Fc reduced peripheral B cell numbers and decreased sialadenitis. In addition, this treatment reduced total serum immunoglobulin as well as IgG and IgM specific anti-nuclear autoantibodies. NOD/ShiLtJ mice treated with BAFFR-Fc and anti-CXCL13 antibody were protected from salivary deficits. Results from this study suggest blockade of CXCL13 and BAFFR together may be an effective therapeutic strategy in preventing salivary hypofunction and reducing autoantibody titers and sialadenitis in patients with SS.

  1. Activation of human factor IX (Christmas factor).

    PubMed Central

    Di Scipio, R G; Kurachi, K; Davie, E W

    1978-01-01

    Human Factor IX (Christmas factor) is a single-chain plasma glycoprotein (mol wt 57,000) that participates in the middle phase of the intrinsic pathway of blood coagulation. It is present in plasma as a zymogen and is converted to a serine protease, Factor IXabeta, by Factor XIa (activated plasma thromboplastin antecedent) in the presence of calcium ions. In the activation reaction, two internal peptide bonds are hydrolyzed in Factor IX. These cleavages occur at a specific arginyl-alanine peptide bond and a specific arginyl-valine peptide bond. This results in the release of an activation peptide (mol wt approximately equal to 11,000) from the internal region of the precursor molecule and the generation of Factor IXabeta (mol wt approximately equal to 46,000). Factor IXabeta is composed of a light chain (mol wt approximately equal to 18,000) and a heavy chain (mol wt approximately equal to 28,000), and these chains are held together by a disulfide bond(s). The light chain originates from the amino terminal portion of the precursor molecule and has an amino terminal sequence of Tyr-Asn-Ser-Gly-Lys. The heavy chain originates from the carboxyl terminal region of the precursor molecule and contains an amino terminal sequence of Val-Val-Gly-Gly-Glu. The heavy chain of Factor IXabeta also contains the active site sequence of Phe-Cys-Ala-Gly-Phe-His-Glu-Gly-Arg-Asp-Ser-Cys-Gln-Gly-Asp-SER-Gly-Gly-Pro. The active site serine residue is shown in capital letters. Factor IX is also converted to Factor IXaalpha by a protease from Russell's viper venom. This activation reaction, however, occurs in a single step and involves only the cleavage of the internal arginyl-valine peptide bond. Human Factor IXabeta was inhibited by human antithrombin III by the formation of a one-to-one complex of enzyme and inhibitor. In this reaction, the inhibitor was tightly bound to the heavy chain of the enzyme. These data indicate that the mechanism of activation of human Factor IX and its

  2. Correction of transposition of the great vessels with previous Baffes procedure.

    PubMed

    Deboer, A; Miller, R; Otto, R

    1975-12-01

    Twenty-four patients with transposition of the great vessels who underwent a Baffes procedure in infancy were totally corrected by a modified Mustard procedure. There were three postoperative deaths and one major complication. All survivors have been followed from 2 to 8 yr and have done well except for one patient who required a tricuspid valve replacement because of tricuspid insufficiency. It is our conclusion that this group of patients can be corrected with a relatively low mortality and a favorable outcome.

  3. Development of systemic lupus erythematosus in NZM 2328 mice in the absence of any single BAFF receptor

    PubMed Central

    Jacob, Chaim O.; Yu, Ning; Guo, Shunhua; Jacob, Noam; Quinn, William J.; Sindhava, Vishal; Cancro, Michael P.; Goilav, Beatrice; Putterman, Chaim; Migone, Thi-Sau; Stohl, William

    2013-01-01

    Objective To determine the necessity for any individual BAFF receptor in the development of SLE. Methods Bcma, Taci, and Br3 null mutations were introgressed into NZM 2328 mice. NZM.Bcma−/−, NZM.Taci−/−, and NZM.Br3−/− mice were evaluated for lymphocyte phenotype and BAFF receptor expression by flow cytometry, B cell responsiveness to BAFF by in vitro culture, serum BAFF and total IgG and IgG anti-dsDNA levels by ELISA, renal immunopathology by immunofluorescence and histopathology, and clinical disease. Results NZM.Bcma−/−, NZM.Taci−/−, and NZM.Br3−/− mice failed to surface-express BCMA, TACI, and BR3, respectively. Transitional and follicular B cells from NZM.Br3−/− mice were much less responsive to BAFF than the corresponding cells from wild-type (WT), NZM.Bcma−/−, or NZM.Taci−/− mice. In comparison to WT mice, NZM.Bcma−/− and NZM.Taci−/− mice harbored increased spleen B cells, T cells, and plasma cells (PC), whereas serum total IgG and IgG anti-dsDNA levels were similar. Despite their paucity of B cells, NZM.Br3−/− mice harbored increased T cells and WT-like numbers of PC and levels of IgG anti-dsDNA. Serum BAFF levels were increased in NZM.Taci−/− and NZM.Br3−/− mice but were decreased in NZM.Bcma−/− mice. Despite their phenotypic differences, renal immunopathology and clinical disease in NZM.Bcma−/−, NZM.Taci−/−, and NZM.Br3−/− mice were at least as severe as in WT mice. Conclusions Any single BAFF receptor, including BR3, is dispensable to development of SLE in NZM mice. Development of disease in NZM.Br3−/− mice demonstrates that BAFF/BCMA and/or BAFF/TACI interactions contribute to SLE and that profound, life-long reduction in B cells does not guarantee protection from SLE. PMID:23334904

  4. B-cell activation in cats with feline infectious peritonitis (FIP) by FIP-virus-induced B-cell differentiation/survival factors.

    PubMed

    Takano, Tomomi; Azuma, Natsuko; Hashida, Yoshikiyo; Satoh, Ryoichi; Hohdatsu, Tsutomu

    2009-01-01

    It has been suggested that antibody overproduction plays a role in the pathogenesis of feline infectious peritonitis (FIP). However, only a few studies on the B-cell activation mechanism after FIP virus (FIPV) infection have been reported. The present study shows that: (1) the ratio of peripheral blood sIg(+) CD21(-) B-cells was higher in cats with FIP than in SPF cats, (2) the albumin-to-globulin ratio has negative correlation with the ratio of peripheral blood sIg(+) CD21(-) B-cell, (3) cells strongly expressing mRNA of the plasma cell master gene, B-lymphocyte-induced maturation protein 1 (Blimp-1), were increased in peripheral blood in cats with FIP, (4) mRNA expression of B-cell differentiation/survival factors, IL-6, CD40 ligand, and B-cell-activating factor belonging to the tumor necrosis factor family (BAFF), was enhanced in macrophages in cats with FIP, and (5) mRNAs of these B-cell differentiation/survival factors were overexpressed in antibody-dependent enhancement (ADE)-induced macrophages. These data suggest that virus-infected macrophages overproduce B-cell differentiation/survival factors, and these factors act on B-cells and promote B-cell differentiation into plasma cells in FIPV-infected cats.

  5. Inhibition of Hageman factor activation

    PubMed Central

    Nossel, H. L.; Rubin, H.; Drillings, M.; Hsieh, R.

    1968-01-01

    A method for studying inhibitors of the contact stages of blood coagulation is described. A number of positively charged substances were shown to inhibit the contact stages. The inhibitory substances include spermine, cytochrome c, ribonuclease, and lysozyme. The inhibitory effect of these substances was neutralized by the addition of an activated plasma thromboplastin antecedent, factor XI, (PTA) fraction. Other positively charged substances including protamine, hexadimethrine, polylysine, polyornithine, methylene blue, and ortho-toluidine blue also inhibited the contact stages of coagulation, but the inhibitory effect on coagulation was not neutralized by the activated PTA fraction. Negatively charged substances such as heparin and insulin did not inhibit the contact stages of coagulation. Cytochrome c inhibited Celite adsorption of a partially purified Hageman factor fraction, and cytochrome, ribonuclease, spermine, and lysozome inhibited the adsorption of Hageman factor from PTA-deficient plasma. Very much smaller quantities of Celite completely adsorbed Hageman factor from the fraction rather than from whole plasma, which suggested the possibility that plasma contains an inhibitor or inhibitors of Hageman factor adsorption. Furthermore cytochrome c, spermine, ribonuclease, and lysozyme inhibited the coagulant activity of the following activators of the Hageman and PTA factors: Celite, kaolin, sodium stearate, ellagic acid, and skin. It is suggested that negatively charged sites on these activators are critical for adsorption and activation and that inhibition results from neutralization of the negatively charged sites by the adsorbed inhibtor. Tests with polylysine polymers indicate that inhibitory activity is directly related to molecular size over the molecular weight range of 4000 to 100,000. PMID:5645860

  6. Psychosocial factors underlying physical activity

    PubMed Central

    Zhang, Juan; Middlestadt, Susan E; Ji, Cheng-Ye

    2007-01-01

    academic achievement and other factors beyond physical health; barriers of not having enough time and having too many assignments perceived to hinder frequent physical activity; and parental approval. More rigorous research on psychosocial determinants with close-ended items developed from these open-ended data and with larger sample sizes of students is necessary. Research with parents and school staff will be needed to understand the perceptions of these stakeholder groups key to creating the students' social environment. PMID:17880688

  7. Current status on tissue factor activation of factor VIIa.

    PubMed

    Persson, Egon; Olsen, Ole H

    2010-04-01

    Free factor VIIa displays a zymogen-like behavior with low intrinsic activity. Formation of a complex between factor VIIa and tissue factor is necessary to enhance the procoagulant activity of factor VIIa, not only by providing membrane localization, substrate exosites and positioning the active site at an appropriate distance above the surface but also by allosteric enhancement of the enzymatic activity, and this event signals initiation of blood coagulation. The interaction is of high affinity and all the domains are engaged at the interface. The crosstalk between the protease domain of factor VIIa, in particular residue Met-306, and the N-terminal domain of tissue factor provides the starting point for the allosteric activation of factor VIIa. The pathway(s) of conformational transitions in factor VIIa ensuing tissue factor binding has not been entirely mapped. The present paper is a brief compilation of our current knowledge of the allosteric mechanism by which tissue factor induces and stabilizes the active conformation of factor VIIa.

  8. Chemokine/cytokine profiling after rituximab: reciprocal expression of BCA-1/CXCL13 and BAFF in childhood OMS.

    PubMed

    Pranzatelli, Michael R; Tate, Elizabeth D; Travelstead, Anna L; Verhulst, Steven J

    2011-03-01

    The aim of the study was to test the hypothesis that B-cell repopulation following rituximab (anti-CD20) therapy is orchestrated by chemokines and non-chemokine cytokines. Twenty-five children with opsoclonus-myoclonus syndrome (OMS) received rituximab with or without conventional agents. A comprehensive panel of 40 chemokines and other cytokines were measured in serum by ELISA and multiplexed fluorescent bead-based immunoassay. Serum BAFF concentration changed dramatically (even after first infusion) and inversely with B-cell depletion/repopulation and CXCL13 concentration at 1, 3, and 6 months. Negative correlations were found for BAFF concentration vs blood B cell percentage and serum CXCL13 concentration; positive correlations with serum rituximab concentrations. Six months after initiation of therapy, no significant difference in the levels of APRIL, CXCL10, IL-6, or 17 other cytokines/chemokines were detected. These data reveal a major role for BAFF in peripheral B cell repopulation following rituximab-induced B-cell depletion, and novel changes in CXCL13. ClinicalTrials.gov NCT0024436.

  9. Activation of hageman factor by collagen

    PubMed Central

    Wilner, G. D.; Nossel, H. L.; LeRoy, E. C.

    1968-01-01

    Purified acid-soluble and insoluble human collagen accelerated the clotting of plateletpoor plasma in silicone-treated tubes. The clot-promoting effect did not appear to be due to thromboplastic activity since the collagen preparations did not activate factor X in the presence of factor VII and calcium. Instead, collagen appeared to accelerate clotting by activating Hageman factor (factor XII) on the basis of the following findings: collagen increased the clot-promoting activity of partially purified Hageman factor but exerted no further effect in the presence of kaolin, a known activator of Hageman factor; clot-promoting eluates were obtained from collagen exposed to normal, hemophilic, or PTC-deficient plasma but not from collagen exposed to Hageman or PTA-deficient plasma. The collagen molecule itself appeared to be required for the clot-promoting activity since digestion with collagenase or thermal denaturation at pH 2.5 (about 35°C) resulted in very marked reduction in clot-promoting activity. Since thermal denaturation is associated with transformation of collagen structure from triple helical to random coil form, it is suggested that the native form of collagen is essential for the ability to activate Hageman factor. Blockage of the free amino groups by treatment with nitrous acid or dinitrofluorobenzene only slightly reduced the clot-promoting activity of collagen. In contrast, since addition of cationic proteins to collagen markedly reduced pro-coagulant activity it is suggested that negatively charged sites on the collagen molecule are critical for Hageman factor activation. This suggestion is supported by the finding that pepsin treatment of collagen, which removes the predominantly negatively charged telopeptides, results in significant decrease in coagulant activity. Esterification of collagen, which neutralizes 80-90% of the free carboxyl groups, reduced coagulant activity by over 90% and it is suggested that the free carboxyl groups of glutamic and

  10. Cellular competition independent of BAFF/BLyS results in low frequency of an autoreactive clonotype in mature polyclonal B cell compartments1

    PubMed Central

    Nikbakht, Neda; Migone, Thi-Sau; Ward, Chris P.; Manser, Tim

    2011-01-01

    The peripheral B cell pro-survival cytokine BAFF/BLyS has been proposed to participate in the regulation of immunological tolerance. Selective elimination or reconstitution of B cells expressing transgene-encoded, autoreactive BCRs upon systemic BLyS depletion or supplementation, respectively, was observed in two separate studies. Such findings led to a model positing a higher dependency of autoreactive B cells on BLyS. We tested this model by exploiting two targeted Ig heavy chain transgenic mice (HKI) that produce large numbers of follicular (FO) B cells that are either weakly or strongly autoreactive with nuclear autoantigens. Even though HKI B cells do not exhibit classical features of anergy, we found that mature, naïve, autoreactive HKI B cells are out-competed for representation in the periphery by a polyclonal B cell population. However, this is not due to a higher dependency of HKI B cells on BLyS for survival. In addition, excess BLyS does not rescue HKI B cells from selective elimination. These findings suggest that some autoreactive FO B cells can fully develop while in competition with non-autoreactive cells for BLyS, but remain at a competitive disadvantage for other trophic factors that regulate peripheral stability. As such, our data indicate the existence of peripheral tolerance mechanisms that regulate the frequency of autoreactive FO B cells independent of the BLyS pathway. PMID:21632709

  11. Tissue factor activity under flow.

    PubMed

    Diamond, Scott L

    2010-04-01

    Coagulation processes under flow conditions are fundamentally different when compared to whole blood clotting in a tube. Due to red blood cell migration toward the center of the vessel, platelet concentrations are elevated several-fold in the plasma layer near the wall or thrombus. Evaluation of platelet function, coagulation proteases, and pharmacological agents can utilize closed systems of constant volume that lack flow (eg. intracellular calcium measurement, automated calibrated thrombography) or include flow (eg. aggregometry or cone-and-plate viscometry). However, these laboratory approaches fail to recreate the fact that intravascular thrombosis is an open system where blood is continually flowing over a thrombotic site. In open systems, the rapid accumulation of platelets at a surface leads to platelet concentrations greatly exceeding those found in whole blood and the delivery/removal of species by convection may impact the efficacy of pharmacological agents. During a clotting event under flow, platelets can accumulate via adhesion receptors to concentrations that are 10 to 50-fold higher than that of platelet-rich plasma. Using controlled in vitro perfusions of whole blood, it is possible to determine the critical level of surface tissue factor needed to trigger full scale coagulation on collagen. Such in vitro perfusion systems also allow a determination of the potency of anti-platelet agents as a function of wall shear rate.

  12. Activation of factor X by rat hepatocytes

    SciTech Connect

    Willingham, A.K.; Matschiner, J.T.

    1986-05-01

    Synthesis and secretion of blood coagulation factor X was studied in hepatocytes prepared by perfusion of rat livers with collagenase. Hepatocytes were incubated in the presence of vitamin K and /sup 3/H-leucine for up to 4h at 37/sup 0/C. Factor X was isolated from the incubation medium by immunochemical techniques and analyzed by SDS-PAGE. The recovered /sup 3/H-labeled proteins migrated, after reduction of disulfides, as two polypeptide chains with apparent molecular weights (M/sub r/) of approximately 42,000 and 22,000 representing the heavy and light chains of factor X respectively. The apparent M/sub r/ of the heavy chain was about 10,000 daltons lighter than seen with the heavy chain of factor X isolated from rat plasma and was more characteristic of the heavy chain of factor Xa. When the levels of factor X secreted by hepatocytes were determined by clotting assays, activity was present as factor Xa. Also, when purified plasma factor X was added to incubations of hepatocytes (>95% parenchymal cells) the added factor X was rapidly converted to factor Xa. Plasma membranes prepared from isolated hepatocytes or from liver homogenates contained an enzyme that converted factor X to factor Xa in a calcium dependent reaction. The physiological significance of a factor X activating enzyme on hepatocyte plasma membranes is not clear.

  13. Inhibition of the activation of Hageman factor (factor XII) by platelet factor 4.

    PubMed

    Dumenco, L L; Everson, B; Culp, L A; Ratnoff, O D

    1988-09-01

    Platelet factor 4 is a polypeptide constituent of platelet alpha granules that is released during platelet aggregation and inhibits heparin-mediated reactions. Hageman factor (factor XII) is a plasma proenzyme that, when activated by certain negatively charged agents, initiates clotting via the intrinsic pathway of thrombin formation. In earlier studies using crude systems, platelet factor 4 inhibited activation of Hageman factor by dextran sulfate or cerebrosides, but not activation of Hageman factor by kaolin or ellagic acid. In the present study we examined the mechanisms of inhibition by platelet factor 4, using purified reagents. Platelet factor 4 inhibited activation of Hageman factor by ellagic acid, as measured by amidolysis of a synthetic substrate of activated Hageman factor, an effect inhibited by heparin or by an anti-platelet factor 4 antiserum. Coating glass tubes with platelet factor 4 before addition of normal plasma significantly lengthened the partial thromboplastin time of normal plasma. In addition, the clot-promoting properties of kaolin were inhibited by its prior exposure to platelet factor 4. Thus, the inhibitory properties of platelet factor 4 directed against the activation of Hageman factor were confirmed in a purified system. In this purified system, in contrast to earlier studies using crude systems, platelet factor 4 inhibited activation of Hageman factor by glass, ellagic acid, or kaolin.

  14. Activation of factor XII by tobacco glycoprotein.

    PubMed

    Becker, C G; Dubin, T

    1977-08-01

    A glycoprotein of mol wt ca. 18,000 daltons isolated from cured tobacco leaves (TGP-L) and from cigarette smoke condensate (TGP-CSC) activated factor XII in normal human plasma in vitro as measured by (a) shortening of the partial thromboplastin time, (b) shortening of the lysis time of euglobulin clots, and (c) generation of kinin activity. These effects were not demonstrable in plasma deficient in factor XII. The capacity of TGP-L and TGP-CSC to activate factor XII was shown to depend on the presence of rutin, a substance chemically similar to quercetin and ellagic acid, which are known activators of factor XII. Rutin and rutin coupled to bovine serum albumin, but not bovine serum albumin alone, were also demonstrated to activate factor XII. The presence in cigarette smoke of material that is both allergenic and capable of activating factor XII of the intrinsic pathway of coagulatin may be important to the pathogenesis of cardiovascular and pulmonary disease associated with cigarette smoking.

  15. Activation of factor XII by tobacco glycoprotein

    PubMed Central

    1977-01-01

    A glycoprotein of mol wt ca. 18,000 daltons isolated from cured tobacco leaves (TGP-L) and from cigarette smoke condensate (TGP-CSC) activated factor XII in normal human plasma in vitro as measured by (a) shortening of the partial thromboplastin time, (b) shortening of the lysis time of euglobulin clots, and (c) generation of kinin activity. These effects were not demonstrable in plasma deficient in factor XII. The capacity of TGP-L and TGP-CSC to activate factor XII was shown to depend on the presence of rutin, a substance chemically similar to quercetin and ellagic acid, which are known activators of factor XII. Rutin and rutin coupled to bovine serum albumin, but not bovine serum albumin alone, were also demonstrated to activate factor XII. The presence in cigarette smoke of material that is both allergenic and capable of activating factor XII of the intrinsic pathway of coagulatin may be important to the pathogenesis of cardiovascular and pulmonary disease associated with cigarette smoking. PMID:874423

  16. BAFF, APRIL, TWEAK, BCMA, TACI and Fn14 proteins are related to human glioma tumor grade: immunohistochemistry and public microarray data meta-analysis.

    PubMed

    Pelekanou, Vassiliki; Notas, George; Kampa, Marilena; Tsentelierou, Eleftheria; Stathopoulos, Efstathios N; Tsapis, Andreas; Castanas, Elias

    2013-01-01

    Gliomas are common and lethal tumors of the central nervous system (CNS). Genetic alterations, inflammatory and angiogenic processes have been identified throughout tumor progression; however, treatment still remains palliative for most cases. Biological research on parameters influencing cell survival, invasion and tumor heterogeneity identified several cytokines interfering in CNS inflammation, oxidative stress and malignant transformation, including TNF-superfamily (TNFSF) members. In this report we performed a meta-analysis of public gene-array data on the expression of a group of TNFSF ligands (BAFF, APRIL, TWEAK) and their receptors (BAFF-R, TACI, BCMA, Fn14) in gliomas. In addition, we investigated by immunohistochemistry (IHC) the tumor cells' expression of these ligands and receptors in a series of 56 gliomas of different grade. We show that in IHC, BAFF and APRIL as well as their cognate receptors (BCMA, TACI) and Fn14 expression correlate with tumor grade. This result was not evidenced in micro-arrays meta-analysis. Finally, we detected for the first time Fn14, BAFF, BCMA and TACI in glioma-related vascular endothelium. Our data, combined with our previous report in glioma cell lines, suggest a role for these receptors and ligands in glioma biology and advance these molecules as potential markers for the classification of these tumors to the proliferative, angiogenic or stem-like molecular subtype.

  17. [B lymphocyte stimulator (BLyS/BAFF) level in sera of patients with lupus].

    PubMed

    Mercado, Ulises; Díaz-Molina, Raúl

    2016-01-01

    Introducción: el estimulador de linfocitos B (BLyS/BAFF) es una proteína endógena fundamental en la diferenciación y la maduración de linfocitos B. En el lupus se han encontrado niveles altos de BLyS. Métodos: se analizaron muestras séricas de 92 pacientes con lupus (94 % mujeres, con una mediana de edad de 35.5) y 106 controles (50 donadores de sangre, 38 pacientes con artritis reumatoide y 18 pacientes con esclerodermia). El punto de corte de BLyS ˃ 1.98 ng/mL corresponde al percentil 95 de los 50 donadores de sangre. También se evaluaron anticuerpos contra ADN nativo y actividad de enfermedad. Durante el seguimiento, los niveles de BLyS en 32 pacientes mostraron heterogeneidad. Resultados: la mediana de BLyS en 92 pacientes con lupus fue de 1.9 ng/mL (rango 0.4-5.3), comparada con 1.30, 1.35, y 1.35 ng/mL en donadores de sangre, pacientes con artritis reumatoide y pacientes con esclerodermia, respectivamente. Treinta y nueve pacientes con lupus tuvieron niveles elevados de BLyS (mediana 2.8 ng/mL), comparados con el grupo control. Hubo una moderada correlación entre títulos de anti-ADN (r = 0.34) y actividad de enfermedad (0.45). El seguimiento de 32 pacientes mostró un nivel de BLyS persistentemente elevado, normal o con variaciones intermitentes. Conclusión: el nivel de BLyS resultó elevado en algunos pacientes con lupus. Hubo una moderada correlación con títulos de anti-ADN y actividad de enfermedad. El seguimiento de 32 pacientes mostró fluctuaciones en los niveles de BLyS.

  18. Factors Associated with Evaluating Public Relations Activities.

    ERIC Educational Resources Information Center

    McElreath, Mark P.

    More than 150 public relations practitioners responded to a survey designed to identify and clarify factors associated with evaluative research in public relations. Responses indicated that (1) no more than half the practitioners formally evaluate their public relations activities on a regular basis; (2) the majority of evaluation is done…

  19. HIV-1 adenoviral vector vaccines expressing multi-trimeric BAFF and 4-1BBL enhance T cell mediated anti-viral immunity.

    PubMed

    Kanagavelu, Saravana; Termini, James M; Gupta, Sachin; Raffa, Francesca N; Fuller, Katherine A; Rivas, Yaelis; Philip, Sakhi; Kornbluth, Richard S; Stone, Geoffrey W

    2014-01-01

    Adenoviral vectored vaccines have shown considerable promise but could be improved by molecular adjuvants. Ligands in the TNF superfamily (TNFSF) are potential adjuvants for adenoviral vector (Ad5) vaccines based on their central role in adaptive immunity. Many TNFSF ligands require aggregation beyond the trimeric state (multi-trimerization) for optimal biological function. Here we describe Ad5 vaccines for HIV-1 Gag antigen (Ad5-Gag) adjuvanted with the TNFSF ligands 4-1BBL, BAFF, GITRL and CD27L constructed as soluble multi-trimeric proteins via fusion to Surfactant Protein D (SP-D) as a multimerization scaffold. Mice were vaccinated with Ad5-Gag combined with Ad5 expressing one of the SP-D-TNFSF constructs or single-chain IL-12p70 as adjuvant. To evaluate vaccine-induced protection, mice were challenged with vaccinia virus expressing Gag (vaccinia-Gag) which is known to target the female genital tract, a major route of sexually acquired HIV-1 infection. In this system, SP-D-4-1BBL or SP-D-BAFF led to significantly reduced vaccinia-Gag replication when compared to Ad5-Gag alone. In contrast, IL-12p70, SP-D-CD27L and SP-D-GITRL were not protective. Histological examination following vaccinia-Gag challenge showed a dramatic lymphocytic infiltration into the uterus and ovaries of SP-D-4-1BBL and SP-D-BAFF-treated animals. By day 5 post challenge, proinflammatory cytokines in the tissue were reduced, consistent with the enhanced control over viral replication. Splenocytes had no specific immune markers that correlated with protection induced by SP-D-4-1BBL and SP-D-BAFF versus other groups. IL-12p70, despite lack of anti-viral efficacy, increased the total numbers of splenic dextramer positive CD8+ T cells, effector memory T cells, and effector Gag-specific CD8+ T cells, suggesting that these markers are poor predictors of anti-viral immunity in this model. In conclusion, soluble multi-trimeric 4-1BBL and BAFF adjuvants led to strong protection from vaccinia

  20. Platelet activating factor activity in the phospholipids of bovine spermatozoa

    SciTech Connect

    Parks, J.E.; Hough, S.; Elrod, C. )

    1990-11-01

    Platelet activating factor (PAF) has been detected in sperm from several mammalian species and can affect sperm motility and fertilization. Because bovine sperm contain a high percentage of ether-linked phospholipid precursors required for PAF synthesis, a study was undertaken to determine the PAF activity of bovine sperm phospholipids. Total lipids of washed, ejaculated bull sperm were extracted, and phospholipids were fractionated by thin-layer chromatography. Individual phospholipid fractions were assayed for PAF activity on the basis of (3H)serotonin release from equine platelets. PAF activity was detected in the PAF fraction (1.84 pmol/mumol total phospholipid) and in serine/inositol (PS/PI), choline (CP), and ethanolamine phosphoglyceride (EP) and cardiolipin (CA) fractions. Activity was highest in the CP fraction (8.05 pmol/mumol total phospholipid). Incomplete resolution of PAF and neutral lipids may have contributed to the activity in the PS/PI and CA fractions, respectively. Phospholipids from nonsperm sources did not stimulate serotonin release. Platelet activation by purified PAF and by sperm phospholipid fractions was inhibited by the receptor antagonist SRI 63-675. These results indicate that bovine sperm contain PAF and that other sperm phospholipids, especially CP and EP, which are high in glycerylether components, are capable of receptor-mediated platelet activation.

  1. Proteolytic Processing Regulates Placental Growth Factor Activities*

    PubMed Central

    Hoffmann, Daniel C.; Willenborg, Sebastian; Koch, Manuel; Zwolanek, Daniela; Müller, Stefan; Becker, Ann-Kathrin A.; Metzger, Stephanie; Ehrbar, Martin; Kurschat, Peter; Hellmich, Martin; Hubbell, Jeffrey A.; Eming, Sabine A.

    2013-01-01

    Placental growth factor (PlGF) is a critical mediator of blood vessel formation, yet mechanisms of its action and regulation are incompletely understood. Here we demonstrate that proteolytic processing regulates the biological activity of PlGF. Specifically, we show that plasmin processing of PlGF-2 yields a protease-resistant core fragment comprising the vascular endothelial growth factor receptor-1 binding site but lacking the carboxyl-terminal domain encoding the heparin-binding domain and an 8-amino acid peptide encoded by exon 7. We have identified plasmin cleavage sites, generated a truncated PlGF118 isoform mimicking plasmin-processed PlGF, and explored its biological function in comparison with that of PlGF-1 and -2. The angiogenic responses induced by the diverse PlGF forms were distinct. Whereas PlGF-2 increased endothelial cell chemotaxis, vascular sprouting, and granulation tissue formation upon skin injury, these activities were abrogated following plasmin digestion. Investigation of PlGF/Neuropilin-1 binding and function suggests a critical role for heparin-binding domain/Neuropilin-1 interaction and its regulation by plasmin processing. Collectively, here we provide new mechanistic insights into the regulation of PlGF-2/Neuropilin-1-mediated tissue vascularization and growth. PMID:23645683

  2. Platelet Activating Factor: A Growth Factor for Breast Cancer

    DTIC Science & Technology

    2006-09-01

    Factor for Breast Cancer PRINCIPAL INVESTIGATOR: Larry W. Daniel, Ph.D. CONTRACTING ORGANIZATION: Wake Forest University...A Growth Factor for Breast Cancer 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-04-1-0682 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Larry W...Relevance: If PAF is found to be a growth and angiogenic factor for breast cancer cells, these studies can be followed up by in vivo studies in nude

  3. Cleavage and activation of human factor IX by serine proteases

    SciTech Connect

    Enfield, D.L.; Thompson, A.R.

    1984-10-01

    Human factor IX circulates as a single-chain glycoprotein. Upon activation in vitro, it is cleaved into disulfide-linked light and heavy chains and an activation peptide. After reduction of activated /sup 125/I-factor IX, the heavy and light chains are readily identified by gel electrophoresis. A direct, immunoradiometric assay for factor IXa was developed to assess activation of factor IX for proteases that cleaved it. The assay utilized radiolabeled antithrombin III with heparin to identify the active site and antibodies to distinguish factor IX. After cleavage of factor IX by factor XIa, factor VIIa-tissue thromboplastin complex, or the factor X-activating enzyme from Russell's viper venom, antithrombin III bound readily to factor IXa. Cleavage of /sup 125/I-factor IX by trypsin, chymotrypsin, and granulocyte elastase in the presence of calcium yielded major polypeptide fragments of the sizes of the factor XIa-generated light and heavy chains. When the immunoradiometric assay was used to assess trypsin-cleaved factor IX, the product bound antithrombin III, but not maximally. After digesting with insolubilized trypsin, clotting activity confirmed activation. In evaluating activation of factor IX, physical evidence of activation cleavages does not necessarily correlate with generation of an active site.

  4. Very low activated factor VII and reduced factor VII antigen in familial abetalipoproteinaemia.

    PubMed

    Miller, G J; Mitropoulos, K A; Nanjee, M N; Howarth, D J; Martin, J C; Esnouf, M P; Reeves, B E; Miller, N E; Cooper, J A

    1998-08-01

    Abetalipoproteinaemia is a rare disorder of apolipoprotein B metabolism associated with extremely low plasma concentrations of triglyceride. To discover whether the general positive association between factor VII and triglyceride levels extends to this condition, 5 patients were compared with 18 controls. All patients had a triglyceride below 100 micromol/l. Plasma unesterified fatty acid concentration was normal. Although factor IX activity was only slightly reduced (mean 88% standard) and factor IX antigen was normal, mean activated factor VII in patients was strikingly reduced to 34% of that in controls, a level similar to that found in haemophilia B. The patients' mean factor VII activity and factor VII antigen were also significantly reduced to 54% and 63% of those in controls, respectively. Mean factor XI activity and tissue factor pathway inhibitor activity were reduced in patients to 70% and 75% of control values respectively, while factor XII, factor XI antigen, factor X, prothrombin and protein C were normal.

  5. Characterization of the clotting activities of structurally different forms of activated factor IX. Enzymatic properties of normal human factor IXa alpha, factor IXa beta, and activated factor IX Chapel Hill.

    PubMed Central

    Griffith, M J; Breitkreutz, L; Trapp, H; Briet, E; Noyes, C M; Lundblad, R L; Roberts, H R

    1985-01-01

    Two structurally different forms of activated human Factor IX (Factor IXa alpha and IXa beta) have been previously reported to have essentially identical clotting activity in vitro. Although it has been shown that activated Factor IX Chapel Hill, an abnormal Factor IX isolated from the plasma of a patient with mild hemophilia B, and normal Factor IXa alpha are structurally very similar, the clotting activity of activated Factor IX Chapel Hill is much lower (approximately fivefold) than that of normal Factor IXa beta. In the present study we have prepared activated Factor IX by incubating human Factor IX with calcium and Russell's viper venom covalently bound to agarose. Fractionation of the activated Factor IX by high-performance liquid chromatography demonstrated the presence of both Factors IXa alpha and IXa beta. On the basis of active site concentration, determined by titration with antithrombin III, the clotting activities of activated Factor IX Chapel Hill and IXa alpha were similar, but both activities were less than 20% of the clotting activity of Factor IXa beta. Activated Factor IX activity was also measured in the absence of calcium, phospholipid, and Factor VIII, by determination of the rate of Factor X activation in the presence of polylysine. In the presence of polylysine, the rates of Factor X activation by activated Factor IX Chapel Hill, Factor IXa alpha, and Factor IXa beta were essentially identical. We conclude that the clotting activity of activated Factor IX Chapel Hill is reduced when compared with that of Factor IXa beta but essentially normal when compared with that of Factor IXa alpha. PMID:3871202

  6. ACTIVATION OF HAGEMAN FACTOR IN SOLID AND FLUID PHASES

    PubMed Central

    Cochrane, C. G.; Revak, S. D.; Wuepper, K. D.

    1973-01-01

    The activation of Hageman factor in solid and fluid phase has been analyzed. Activation of highly purified Hageman factor occurred after it interacted with and became bound to a negatively charged surface. Activation was observed in the absence of enzymes that are inhibitable with diisopropylfluorophosphate, phenyl methyl sulfonyl fluoride and ε-amino-n-caproic acid. The binding of [125I]Hageman factor to the negatively charged surface was markedly inhibited by plasma or purified plasma proteins. Activation of Hageman factor in solution (fluid phase) was obtained with kallikrein, plasmin, and Factor XI (plasma thromboplastin antecedent). Kallikrein was greater than 10 times more active in its ability to activate Hageman factor than plasmin and Factor XI. The data offer a plausible explanation for the finding that highly purified kallikrein promotes clotting of normal plasma. In addition, the combined results of this and previously reported data from this laboratory indicate that the reciprocal activation of Hageman factor by kallikrein in fluid phase is essential for normal rate of activation of the intrinsic-clotting, kinin-forming, and fibrinolytic systems. Activation of Hageman factor was associated with three different structural changes in the molecule: (a) Purified Hageman factor, activated on negatively charged surfaces retained its native mol wt of 80–90,000. Presumably a conformational change accompanied activation. (b) In fluid phase, activation with kallikrein and plasmin did not result in cleavage of large fragments of rabbit Hageman factor, although the activation required hydrolytic capacity of the enzymes. (c) Activation of human Hageman factor with kallikrein or plasmin was associated with cleavage of the molecule to 52,000, 40,000, and 28,000 mol wt fragments. Activation of rabbit Hageman factor with trypsin resulted in cleavage of the molecule into three fragments, each of 30,000 mol wt as noted previously. This major cleavage occurred

  7. Factors Influencing Cypriot Children's Physical Activity Levels

    ERIC Educational Resources Information Center

    Loucaides, Constantinos A.; Chedzoy, Sue M.

    2005-01-01

    The purpose of this paper is to present selected findings from a larger study, which set out to examine the physical activity levels of Cypriot primary school children and determinants of their activity. Twenty parents of children who obtained high and low activity scores based on pedometer counts and self-reports scores were interviewed. By…

  8. Co-factor activated recombinant adenovirus proteinases

    DOEpatents

    Anderson, C.W.; Mangel, W.F.

    1996-08-06

    This application describes methods and expression constructs for producing activatable recombinant adenovirus proteinases. Purified activatable recombinant adenovirus proteinases and methods of purification are described. Activated adenovirus proteinases and methods for obtaining activated adenovirus proteinases are further included. Isolated peptide cofactors of adenovirus proteinase activity, methods of purifying and identifying the peptide cofactors are also described. Antibodies immunoreactive with adenovirus proteinases, immunospecific antibodies, and methods for preparing them are also described. Other related methods and materials are also described. 29 figs.

  9. Co-factor activated recombinant adenovirus proteinases

    DOEpatents

    Anderson, Carl W.; Mangel, Walter F.

    1996-08-06

    This application describes methods and expression constructs for producing activatable recombinant adenovirus proteinases. Purified activatable recombinant adenovirus proteinases and methods of purification are described. Activated adenovirus proteinases and methods for obtaining activated adenovirus proteinases are further included. Isolated peptide cofactors of adenovirus proteinase activity, methods of purifying and identifying said peptide cofactors are also described. Antibodies immunoreactive with adenovirus proteinases, immunospecific antibodies, and methods for preparing them are also described. Other related methods and materials are also described.

  10. Virulence Factor-activity Relationships: Workshop Summary

    EPA Science Inventory

    The concept or notion of virulence factor–activity relationships (VFAR) is an approach for identifying an analogous process to the use of qualitative structure–activity relationships (QSAR) for identifying new microbial contaminants. In QSAR, it is hypothesized that, for new chem...

  11. Kinetics of the Factor XIa catalyzed activation of human blood coagulation Factor IX

    SciTech Connect

    Walsh, P.N.; Bradford, H.; Sinha, D.; Piperno, J.R.; Tuszynski, G.P.

    1984-05-01

    The kinetics of activation of human Factor IX by human Factor XIa was studied by measuring the release of a trichloroacetic acid-soluble tritium-labeled activation peptide from Factor IX. Initial rates of trichloroacetic acid-soluble /sup 3/H-release were linear over 10-30 min of incubation of Factor IX (88 nM) with CaCl/sub 2/ (5 mM) and with pure (greater than 98%) Factor XIa (0.06-1.3 nM), which was prepared by incubating human Factor XI with bovine Factor XIIa. Release of /sup 3/H preceded the appearance of Factor IXa activity, and the percentage of /sup 3/H released remained constant when the mole fraction of /sup 3/H-labeled and unlabeled Factor IX was varied and the total Factor IX concentration remained constant. A linear correlation (r greater than 0.98, P less than 0.001) was observed between initial rates of /sup 3/H-release and the concentration of Factor XIa, measured by chromogenic assay and by radioimmunoassay and added at a Factor IX:Factor XIa molar ratio of 70-5,600. Kinetic parameters, determined by Lineweaver-Burk analysis, include K/sub m/ (0.49 microM) of about five- to sixfold higher than the plasma Factor IX concentration, which could therefore regulate the reaction. The catalytic constant (k/sub cat/) (7.7/s) is approximately 20-50 times higher than that reported by Zur and Nemerson for Factor IX activation by Factor VIIa plus tissue factor. Therefore, depending on the relative amounts of Factor XIa and Factor VIIa generated in vivo and other factors which may influence reaction rates, these kinetic parameters provide part of the information required for assessing the relative contributions of the intrinsic and extrinsic pathways to Factor IX activation, and suggest that the Factor XIa catalyzed reaction is physiologically significant.

  12. TACI deficiency leads to alternatively activated macrophage phenotype and susceptibility to Leishmania infection

    PubMed Central

    Allman, Windy R.; Dey, Ranadhir; Liu, Lunhua; Siddiqui, Shafiuddin; Coleman, Adam S.; Bhattacharya, Parna; Yano, Masahide; Uslu, Kadriye; Takeda, Kazuyo; Nakhasi, Hira L.; Akkoyunlu, Mustafa

    2015-01-01

    The TNF family member, transmembrane activator and calcium-modulator and cyclophilin ligand interactor (TACI), is a key molecule for plasma cell maintenance and is required in infections where protection depends on antibody response. Here, we report that compared with WT mouse, TACI KO Μϕs expressed lower levels of Toll-like receptors (TLRs), CD14, myeloid differentiation primary response protein 88, and adaptor protein Toll/IL-1 receptor domain-containing adapter-inducing IFN-β and responded poorly to TLR agonists. Analysis of Μϕ phenotype revealed that, in the absence of TACI, Μϕs adapt the alternatively activated (M2) phenotype. Steady-state expression levels for M2 markers IL-4Rα, CD206, CCL22, IL-10, Arg1, IL1RN, and FIZZ1 were significantly higher in TACI KO Μϕ than in WT cells. Confirming their M2 phenotype, TACI-KO Mϕs were unable to control Leishmania major infection in vitro, and intradermal inoculation of Leishmania resulted in a more severe manifestation of disease than in the resistant C57BL/6 strain. Transfer of WT Μϕs to TACI KO mice was sufficient to significantly reduce disease severity. TACI is likely to influence Mϕ phenotype by mediating B cell-activating factor belonging to the TNF family (BAFF) and a proliferation inducing ligand (APRIL) signals because both these ligands down-regulated M2 markers in WT but not in TACI-deficient Μϕs. Moreover, treatment of Μϕs with BAFF or APRIL enhanced the clearance of Leishmania from cells only when TACI is expressed. These findings may have implications for understanding the shortcomings of host response in newborns where TACI expression is reduced and in combined variable immunodeficiency patients where TACI signaling is ablated. PMID:26170307

  13. The immunoregulator soluble TACI is released by ADAM10 and reflects B-cell activation in autoimmunity

    PubMed Central

    Hoffmann, Franziska S.; Kuhn, Peer-Hendrik; Laurent, Sarah A.; Hauck, Stefanie M.; Berer, Kerstin; Wendlinger, Simone A.; Krumbholz, Markus; Khademi, Mohsen; Olsson, Tomas; Dreyling, Martin; Pfister, Hans-Walter; Alexander, Tobias; Hiepe, Falk; Kümpfel, Tania; Crawford, Howard C.; Wekerle, Hartmut; Hohlfeld, Reinhard; Lichtenthaler, Stefan F.; Meinl, Edgar

    2014-01-01

    BAFF and APRIL, which control B-cell homeostasis, are therapeutic targets in autoimmune diseases. TACI-Fc (atacicept), a soluble fusion protein containing the extracellular domain of the BAFF-APRIL-receptor TACI, was applied in clinical trials. However disease activity in multiple sclerosis (MS) unexpectedly increased, whereas in systemic lupus erythematosus (SLE) atacicept was beneficial. Here, we show that an endogenous soluble form of TACI exists in vivo. TACI proteolysis involved shedding by ADAM10 releasing sTACI from activated B cells. The membrane-bound stub was subsequently cleaved by γ-secretase reducing ligand-independent signaling of the remaining C-terminal fragment. The shed ectodomain assembled ligand-independently in a homotypic way. It functioned as a decoy receptor inhibiting BAFF- and APRIL-mediated B-cell survival and NFκB-activation. We determined sTACI levels in autoimmune diseases with established hyper-activation of the BAFF-APRIL system. sTACI levels were elevated both in the cerebrospinal fluid (CSF) of the brain-restricted autoimmune disease MS correlating with intrathecal IgG production, as well as in the serum of the systemic autoimmune disease SLE correlating with disease activity. Together, we show that TACI is sequentially processed by ADAM10 and γ-secretase. The released sTACI is an immunoregulator that shares decoy functions with atacicept. Itreflectssystemic and compartmentalized B-cell accumulation and activation. PMID:25505277

  14. Influencing Factors of Thermogenic Adipose Tissue Activity

    PubMed Central

    Zhang, Guoqing; Sun, Qinghua; Liu, Cuiqing

    2016-01-01

    Obesity is an escalating public health challenge and contributes tremendously to the disease burden globally. New therapeutic strategies are required to alleviate the health impact of obesity-related metabolic dysfunction. Brown adipose tissue (BAT) is specialized for dissipating chemical energy for thermogenesis as a defense against cold environment. Intriguingly, the brown-fat like adipocytes that dispersed throughout white adipose tissue (WAT) in rodents and humans, called “brite” or “beige” adipocytes, share similar thermogenic characteristics to brown adipocytes. Recently, researchers have focused on cognition of these thermogenic adipose tissues. Some factors have been identified to regulate the development and function of thermogenic adipose tissues. Cold exposure, pharmacological conditions, and lifestyle can enhance non-shivering thermogenesis and metabolism via some mechanisms. However, environmental pollutants, such as ambient fine particulates and ozone, may impair the function of these thermogenic adipose tissues and thereby induce metabolic dysfunction. In this review, the origin, function and influencing factors of thermogenic adipose tissues were summarized and it will provide insights into identifying new therapeutic strategies for the treatment of obesity and obesity-related diseases. PMID:26903879

  15. Inhibition of the activation of Hageman factor (factor XII) by peripheral blood cells.

    PubMed Central

    Ratnoff, O D; Emanuelson, M M; Ziats, N P

    1987-01-01

    Suspensions of peripheral blood mononuclear cells (PBMC), monocytes, T or B lymphocytes, platelets or granulocytes, and cell-depleted supernatant fluids of these suspensions inhibited activation of Hageman factor (HF, Factor XII) by ellagic acid, a property not shared by erythrocytes. PBMC also inhibited HF activation by glass or sulfatides. Contaminating platelets may have contributed to inhibition by PBMC. Elaboration of agents inhibiting HF activation required metabolically active cells. The inhibitor(s) in PBMC supernates were not identified with known agents, but had properties of a nonenzymatic protein. PBMC supernates did not contain fibrinogen, nor alter the thrombin, prothrombin, or partial thromboplastin times of normal plasma, amidolysis by activated plasma thromboplastin antecedent (Factor XIa) or activated Stuart factor (Factor Xa) or esterolysis by C1 (C1 esterase); they inhibited plasmin minimally. These experiments suggest that peripheral blood cells may impede intravascular coagulation. Whether this property helps maintain the fluidity of blood is unclear. PMID:3498741

  16. Factor XI and Contact Activation as Targets for Antithrombotic Therapy

    PubMed Central

    Gailani, David; Bane, Charles E.; Gruber, Andras

    2015-01-01

    Summary The most commonly used anticoagulants produce therapeutic antithrombotic effects either by inhibiting thrombin or factor Xa, or by lowering the plasma levels of the precursors of these key enzymes, prothrombin and factor X. These drugs do not distinguish between thrombin generation contributing to thrombosis from thrombin generation required for hemostasis. Thus, anticoagulants increase bleeding risk, and many patients who would benefit from therapy go untreated because of comorbidities that place them at unacceptable risk for hemorrhage. Studies in animals demonstrate that components of the plasma contact activation system contribute to experimentally-induced thrombosis, despite playing little or no role in hemostasis. Attention has focused on factor XII, the zymogen of a protease (factor XIIa) that initiates contact activation when blood is exposed to foreign surfaces; and factor XI, the zymogen of the protease factor XIa, which links contact activation to the thrombin generation mechanism. In the case of factor XI, epidemiologic data indicate this protein contributes to stroke and venous thromboembolism, and perhaps myocardial infarction, in humans. A phase 2 trial showing that reduction of factor XI may be more effective than low-molecular-weight heparin at preventing venous thrombosis during knee replacement surgery provides proof of concept for the premise that an antithrombotic effect can be uncoupled from an anticoagulant effect in humans by targeting components of contact activation. Here we review data on the role of factor XI and factor XII in thrombosis, and results of pre-clinical and human trials for therapies targeting these proteins. PMID:25976012

  17. Socioeconomic Factors Influence Physical Activity and Sport in Quebec Schools

    ERIC Educational Resources Information Center

    Morin, Pascale; Lebel, Alexandre; Robitaille, Éric; Bisset, Sherri

    2016-01-01

    Background: School environments providing a wide selection of physical activities and sufficient facilities are both essential and formative to ensure young people adopt active lifestyles. We describe the association between school opportunities for physical activity and socioeconomic factors measured by low-income cutoff index, school size…

  18. Drosophila factor 2, an RNA polymerase II transcript release factor, has DNA-dependent ATPase activity.

    PubMed

    Xie, Z; Price, D

    1997-12-12

    Drosophila factor 2 has been identified as a component of negative transcription elongation factor (N-TEF) that causes the release of RNA polymerase II transcripts in an ATP-dependent manner (Xie, Z. and Price D. H. (1996) J. Biol. Chem. 271, 11043-11046). We show here that the transcript release activity of factor 2 requires ATP or dATP and that adenosine 5'-O-(thiotriphosphate) (ATPgammaS), adenosine 5'-(beta,gamma-imino)triphosphate (AMP-PNP), or other NTPs do not support the activity. Factor 2 demonstrated a strong DNA-dependent ATPase activity that correlated with its transcript release activity. At 20 microg/ml DNA, the ATPase activity of factor 2 had an apparent Km(ATP) of 28 microM and an estimated Kcat of 140 min-1. Factor 2 caused the release of nascent transcripts associated with elongation complexes generated by RNA polymerase II on a dC-tailed template. Therefore, no other protein cofactors are required for the transcript release activity of factor 2. Using the dC-tailed template assay, it was found that renaturation of the template was required for factor 2 function.

  19. Expression of protooncogenes during lymphocyte activation by growth factors.

    PubMed

    Bulanova, E G; Budagyan, V M; Yarilin, A A; Mazurenko, N N

    1997-09-01

    Effects of growth factors of non-immune origin including somatotropin (ST) and platelet-derived growth factor (PDGF) on the expression of the proteins encoded by c-fos, c-myc, c-fun, and c-ets family protooncogenes were studied for the first time. The dynamics of the oncoprotein expression in activated CD(3+)-lymphocytes was investigated by immunoblotting. The accumulation of the Fos and Myc proteins was enhanced in T-lymphocytes treated with ST, PDGF, or phytohemagglutinin; the accumulation was maximum at 30-60 min and decreased in 2 h; the data indicate that the oncoproteins participate in the early lymphocyte activation by various growth factors. The Jun protein appears only in 3 h after the onset of lymphocyte activation; this suggests independent participation of Fos in the early stages of lymphocyte activation prior to the appearance of Jun, preceding the joint action of Fos and Jun within the AP-1 transcription complex. The products of the c-ets family are differentially activated by the studied growth factors. Resting lymphocytes actively accumulate the Ets-1 protein; ST and PDGF activation decreases Ets-1 expression in 2 h. The Ets-2 protein is not detected in resting cells and PDGF-activated lymphocytes, whereas lymphocyte activation by ST is associated with accumulation of Ets-2. The data suggest that the product of the c-ets-1 gene is more important in the regulation of resting cells and the product of the c-ets-2 gene is important during activation of lymphocytes by ST. The results indicate that activation of lymphocytes with growth factors of non-immune origin is mediated by several signal transduction pathways.

  20. Differential proteolytic activation of factor VIII-von Willebrand factor complex by thrombin

    SciTech Connect

    Hill-Eubanks, D.C.; Parker, C.G.; Lollar, P. )

    1989-09-01

    Blood coagulation factor VIII (fVIII) is a plasma protein that is decreased or absent in hemophilia A. It is isolated as a mixture of heterodimers that contain a variably sized heavy chain and a common light chain. Thrombin catalyzes the activation of fVIII in a reaction that is associated with cleavages in both types of chain. The authors isolated a serine protease from Bothrops jararacussu snake venom that catalyzes thrombin-like heavy-chain cleavage but not light-chain cleavage in porcine fVIII as judged by NaDodSO{sub 4}/PAGE and N-terminal sequence analysis. Using a plasma-free assay of the ability of activated {sup 125}I-fVIII to function as a cofactor in the activation of factor X by factor IXa, they found that fVIII is activated by the venom enzyme. The venom enzyme-activated fVIII was isolated in stable form by cation-exchange HPLC. von Willebrand factor inhibited venom enzyme-activated fVIII but not thrombin-activated fVIII. These results suggest that the binding of fVIII to von Willebrand factor depends on the presence of an intact light chain and that activated fVIII must dissociate from von Willebrand factor to exert its cofactor effect. Thus, proteolytic activation of fVIII-von Willebrand factor complex appears to be differentially regulated by light-chain cleavage to dissociate the complex and heavy-chain cleavage to activate the cofactor function.

  1. Carp thrombocyte phagocytosis requires activation factors secreted from other leukocytes.

    PubMed

    Nagasawa, Takahiro; Somamoto, Tomonori; Nakao, Miki

    2015-10-01

    Thrombocytes are nucleated blood cells in non-mammalian vertebrates, which were recently focused on not only as hemostatic cells but also as immune cells with potent phagocytic activities. We have analyzed the phagocytic activation mechanisms in common carp (Cyprinus carpio) thrombocytes. MACS-sorted mAb(+) thrombocytes showed no phagocytic activity even in the presence of several stimulants. However, remixing these thrombocytes with other anti-thrombocyte mAb(-) leukocyte populations restored their phagocytic activities, indicating that carp thrombocyte phagocytosis requires an appropriate exogenous stimulation. Culture supernatant from anti-thrombocyte mAb(-) leukocytes harvested after PMA or LPS stimulation, but not culture supernatant from unstimulated leukocytes, could activate thrombocyte phagocytosis. This proposed mechanism of thrombocyte phagocytosis activation involving soluble factors produced by activated leukocytes suggests that thrombocyte activation is restricted to areas proximal to injured tissues, ensuring suppression of excessive thrombocyte activation and a balance between inflammation and tissue repair.

  2. Comparison of kaolin and tissue factor activated thromboelastography in haemophilia.

    PubMed

    Young, G; Zhang, R; Miller, R; Yassin, D; Nugent, D J

    2010-05-01

    A limitation of bypassing agent therapy for haemophilia patients with inhibitors is the absence of a laboratory assay, which predicts the clinical response to treatment. Recent investigations have demonstrated the potential for thromboelastography to assess the effects of bypassing agent therapy in this patient population. While tissue factor activation has been used in several prior studies, a recent multicentre study failed to demonstrate an expected concentration-response effect of rFVIIa and called into question the tissue factor activation methods that have been employed. A comparison of kaolin to two concentrations of tissue factor as the activation method for thromboelastography was investigated in patients with haemophilia. We performed kaolin and tissue factor activated thromboelastography on blood from inhibitor and non-inhibitor patients with and without addition of rFVIIa and rFVIII. The results demonstrate that kaolin leads to a longer R, K and angle than the higher dilution of tissue factor (1:17 000) at baseline (no factor) and after addition of rFVIIa for both the inhibitor and non-inhibitor patients. Kaolin led to a longer R and K in comparison to a low dilution of tissue factor (1:42 000) following the addition of rFVIIa in the inhibitor patients. The longer R and K allows for better discrimination of the effects of rFVIIa thus making kaolin the most sensitive activation method in this setting. Thus kaolin activated thromboelastography should be considered an effective, perhaps the most effective, activator when utilizing thromboelastography to assess the effects of rFVIIa in haemophilia patients with inhibitors.

  3. Growth factor control of epidermal growth factor receptor kinase activity via an intramolecular mechanism.

    PubMed

    Koland, J G; Cerione, R A

    1988-02-15

    The mechanism by which the protein kinase activity of the epidermal growth factor (EGF) receptor is activated by binding of growth factor was investigated. Detergent-solubilized receptor in monomeric form was isolated by sucrose density gradient centrifugation and both its kinase and autophosphorylation activities monitored. In a low ionic strength medium and with MnCl2 as an activator, the activity of the monomeric receptor was EGF-independent. However, with 0.25 M ammonium sulfate present, the MnCl2-stimulated kinase activity was strikingly EGF-dependent. In contrast, the kinase activity expressed in the presence of MgCl2 showed growth factor control in the absence of added salt. Under the conditions of these experiments there was apparently little tendency for growth factor to induce aggregation of the receptor, indicating that the allosteric activation of the receptor kinase by EGF occurred via an intramolecular mechanism. Whereas detergent-solubilized receptor was the subject of these studies, the kinase activity of cell surface receptors might also be controlled by an intramolecular mechanism. These results indicate that an individual receptor molecule has the potential to function as a transmembrane signal transducer.

  4. Active site amino acid sequence of human factor D.

    PubMed

    Davis, A E

    1980-08-01

    Factor D was isolated from human plasma by chromatography on CM-Sephadex C50, Sephadex G-75, and hydroxylapatite. Digestion of reduced, S-carboxymethylated factor D with cyanogen bromide resulted in three peptides which were isolated by chromatography on Sephadex G-75 (superfine) equilibrated in 20% formic acid. NH2-Terminal sequences were determined by automated Edman degradation with a Beckman 890C sequencer using a 0.1 M Quadrol program. The smallest peptide (CNBr III) consisted of the NH2-terminal 14 amino acids. The other two peptides had molecular weights of 17,000 (CNBr I) and 7000 (CNBr II). Overlap of the NH2-terminal sequence of factor D with the NH2-terminal sequence of CNBr I established the order of the peptides. The NH2-terminal 53 residues of factor D are somewhat more homologous with the group-specific protease of rat intestine than with other serine proteases. The NH2-terminal sequence of CNBr II revealed the active site serine of factor D. The typical serine protease active site sequence (Gly-Asp-Ser-Gly-Gly-Pro was found at residues 12-17. The region surrounding the active site serine does not appear to be more highly homologous with any one of the other serine proteases. The structural data obtained point out the similarities between factor D and the other proteases. However, complete definition of the degree of relationship between factor D and other proteases will require determination of the remainder of the primary structure.

  5. Protein kinase C-associated kinase regulates NF-κB activation through inducing IKK activation.

    PubMed

    Kim, Sang-Woo; Schifano, Matthew; Oleksyn, David; Jordan, Craig T; Ryan, Daniel; Insel, Richard; Zhao, Jiyong; Chen, Luojing

    2014-10-01

    Activation of the transcription factor NF-κB induced by extracellular stimuli requires IKKα and IKKβ kinase activity. How IKKα and IKKβ are activated by various upstream signaling molecules is not fully understood. We previously showed that protein kinase C-associated kinase (PKK, also known as DIK/RIP4), which belongs to the receptor-interacting protein (RIP) kinase family, mediates the B cell activating factor of the TNF family (BAFF)-induced NF-κB activation in diffuse large B cell lymphoma (DLBCL) cell lines. Here we have investigated the mechanism underlying NF-κB activation regulated by PKK. Our results suggest that PKK can activate both the classical and the alternative NF-κB activation pathways. PKK associates with IKKα and IKKβ in mammalian cells and induces activation of both IKKα and IKKβ via phosphorylation of their serine residues 176/180 and 177/181, respectively. Unlike other members of the RIP family that activate NF-κB through a kinase-independent pathway, PKK appears to activate IKK and NF-κB mainly in a kinase-dependent manner. Suppression of PKK expression by RNA interference inhibits phosphorylation of IKKα and IKKβ as well as activation of NF-κB in human cancer cell lines. Thus, PKK regulates NF-κB activation by modulating activation of IKKα and IKKβ in mammalian cells. We propose that PKK may provide a critical link between IKK activation and various upstream signaling cascades, and may represent a potential target for inhibiting abnormal NF-κB activation in human cancers.

  6. Regulation of tissue factor coagulant activity on cell surfaces

    PubMed Central

    RAO, L.V.M.; PENDURTHI, U.R.

    2012-01-01

    Summary Tissue factor (TF) is a transmembrane glycoprotein and an essential component of factor VIIa-TF enzymatic complex that triggers activation of the coagulation cascade. Formation of TF-FVIIa complexes on cell surfaces not only trigger the coagulation cascade but also transduce cell signaling via activation of protease-activated receptors. Tissue factor is expressed constitutively on cell surfaces of a variety of extravascular cell types, including fibroblasts and pericytes in and surrounding blood vessel walls and epithelial cells but generally absent on cells that come in contact with blood directly. However, TF expression could be induced in some blood cells, such as monocytes and endothelial cells, following an injury or pathological stimuli. Tissue factor is essential for hemostasis, but aberrant expression of TF leads to thrombosis. Therefore, a proper regulation of TF activity is critical for the maintenance of hemostatic balance and health in general. TF-FVIIa coagulant activity at the cell surface is influenced not only by TF protein expression levels but also independently by a variety of mechanisms, including alterations in membrane phospholipid composition and cholesterol content, thiol-dependent modifications of TF allosteric disulfide bond, and other post-translational modifications of TF. In this article, we critically review key literature on mechanisms by which TF coagulant activity is regulated at the cell surface in the absence of changes in TF protein levels with specific emphasis on recently published data and provide the authors’ perspective on the subject. PMID:23006890

  7. Formation of tissue factor activity following incubation of recombinant human tissue factor apoprotein with plasma lipoproteins

    SciTech Connect

    Sakai, T.; Kisiel, W. )

    1990-11-01

    Incubation of recombinant human tissue factor apoprotein (Apo-TF) with human plasma decreased the recalcified clotting time of this plasma in a time-and dose-dependent manner suggesting relipidation of the Apo-TF by plasma lipoproteins. Incubation of Apo-TF with purified preparations of human very low density, low density and high density lipoproteins resulted in tissue factor activity in a clotting assay. The order of effectiveness was VLDL greater than LDL much greater than HDL. Tissue factor activity generated by incubation of a fixed amount of Apo-TF with plasma lipoproteins was lipoprotein concentration-dependent and saturable. The association of Apo-TF with lipoprotein particles was supported by gel filtration studies in which {sup 125}I-Apo-TF coeluted with the plasma lipoprotein in the void volume of a Superose 6 column in the presence and absence of calcium ions. In addition, void-volume Apo-TF-lipoprotein fractions exhibited tissue factor activity. These results suggest that the factor VIII-bypassing activity of bovine Apo-TF observed in a canine hemophilic model may be due, in part, to its association with plasma lipoproteins and expression of functional tissue factor activity.

  8. Activated factor XI increases the procoagulant activity of the extrinsic pathway by inactivating tissue factor pathway inhibitor

    PubMed Central

    Tucker, Erik I.; Matafonov, Anton; Cheng, Qiufang; Zientek, Keith D.; Gailani, Dave; Gruber, András; McCarty, Owen J. T.

    2015-01-01

    Activation of coagulation factor XI (FXI) may play a role in hemostasis. The primary substrate of activated FXI (FXIa) is FIX, leading to FX activation (FXa) and thrombin generation. However, recent studies suggest the hemostatic role of FXI may not be restricted to the activation of FIX. We explored whether FXI could interact with and inhibit the activity of tissue factor pathway inhibitor (TFPI). TFPI is an essential reversible inhibitor of activated factor X (FXa) and also inhibits the FVIIa-TF complex. We found that FXIa neutralized both endothelium- and platelet-derived TFPI by cleaving the protein between the Kunitz (K) 1 and K2 domains (Lys86/Thr87) and at the active sites of the K2 (Arg107/Gly108) and K3 (Arg199/Ala200) domains. Addition of FXIa to plasma was able to reverse the ability of TFPI to prolong TF-initiated clotting times in FXI- or FIX-deficient plasma, as well as FXa-initiated clotting times in FX-deficient plasma. Treatment of cultured endothelial cells with FXIa increased the generation of FXa and promoted TF-dependent fibrin formation in recalcified plasma. Together, these results suggest that the hemostatic role of FXIa may be attributed not only to activation of FIX but also to promoting the extrinsic pathway of thrombin generation through inactivation of TFPI. PMID:25587039

  9. Factors limiting microbial activity in volcanic tuff at Yucca Mountain

    SciTech Connect

    Kieft, T.L.; Kovacik, W.P.; Taylor, J.

    1996-09-01

    Samples of tuff aseptically collected from 10 locations in the Exploratory Shaft Facility at the site of the proposed high-level nuclear waste repository at Yucca Mountain, Nevada Test Site were analyzed for microbiological populations, activities, and factors limiting microbial activity. Radiotracer assays ({sup 14}C-labeled organic substrate mineralization), direct microscopic counts, and plate counts were used. Radiolabeled substrates were glucose, acetate, and glutamate. Radiotracer experiments were carried out with and without moisture and inorganic nutrient amendments to determine factors limiting to microbial activities. Nearly all samples showed the presence of microorganisms with the potential to mineralize organic substrates. Addition of inorganic nutrients stimulated activities in a small number of samples. The presence of viable microbial communities within the tuff has implications for transport of contaminants.

  10. The effect of B-cell depletion therapy on serological evidence of B-cell and plasmablast activation in patients with rheumatoid arthritis over multiple cycles of rituximab treatment.

    PubMed

    Cambridge, G; Perry, H C; Nogueira, L; Serre, G; Parsons, H M; De La Torre, I; Dickson, M C; Leandro, M J; Edwards, J C W

    2014-05-01

    B-cell depletion therapy (BCDT) based on rituximab (RTX) induces clinical remission in a majority of seropositive patients with Rheumatoid arthritis (RA). However, all patients eventually relapse. The aim of this study was to determine whether dynamic changes in combinations of serological measures of B-cell activation were associated over up to three cycles of BCDT. We included only RA patients who gave an adequate clinical response, as measured by DAS28. Twenty three patients were studied over 1 cycle, 21 over 2, and 15 over 3 cycles of BCDT. Serum analytes including isotypes of Rheumatoid factors (RhF) and anti-citrullinated protein/peptide antibodies (ACPA), B-cell activating factor (BAFF), serum free light chains (SFLC), soluble CD23 (sCD23), antibodies to tetanus toxoid (TT) and to pneumococcal capsular polysaccharide (PCP) were measured by ELISA at 4 key points in each cycle, namely: Baseline (pre-RTX in each cycle); when B-cell depleted (CD19+B-cells < 5/μl); at B-cell return (CD19+B-cells ≥ 5/μl); and at clinical relapse (ΔDAS28 > 1.2). SFLC were used as a measure of plasmablast activity. As sCD23 is cleaved from naïve B-cells coincident with attaining CD27 expression, levels were used as a novel measure of maturation of B-cells to CD27+. The most consistent changes between baseline and B-cell depletion within all 3 cycles were in SFLC, sCD23 and IgM-RhF which fell and in BAFF levels which rose. After 3 complete cycles of BCDT, both IgM autoantibodies and IgG-CCP had decreased, BAFF levels were higher (all p < 0.05); other analytes remained unchanged compared with baseline. Dynamic changes in λSFLC, sCD23, IgM-RhF and BAFF were also consistently associated with relapse in patients with longer clinical responses after B-cell return. Incremental rises in sCD23 levels in cycles 2 and 3 were correlated with time to relapse. Repopulation of the periphery after BCDT is initiated by naïve B-cells and precedes relapse. Our study showed that

  11. Control of transforming growth factor-beta activity: latency vs. activation.

    PubMed

    Harpel, J G; Metz, C N; Kojima, S; Rifkin, D B

    1992-01-01

    Transforming growth factor-beta is a pluripotent regulator of cell growth and differentiation. The growth factor is expressed as a latent complex that must be converted to an active form before interacting with its ubiquitous high affinity receptors. This conversion involves the release of the mature growth factor through disruption of the non-covalent interactions with its pro-peptide or latency associated peptide. The mechanisms for this release in vivo have not been fully characterized but appear to be cell specific and might involve processes such as acidification or proteolysis. Although several factors including transcriptional regulation, receptor modulation and scavenging of the active growth factor have been implicated, the critical step controlling the biological effects of transforming growth factor-beta may be the activation of the latent molecule.

  12. Factors Influencing Teachers' Engagement in Informal Learning Activities

    ERIC Educational Resources Information Center

    Lohman, Margaret C.

    2006-01-01

    Purpose: The purpose of this study is to examine factors influencing the engagement of public school teachers in informal learning activities. Design/methodology/approach: This study used a survey research design. Findings: Analysis of the data found that teachers rely to a greater degree on interactive than on independent informal learning…

  13. The Relevant Factors in Promoting Reading Activities in Elementary Schools

    ERIC Educational Resources Information Center

    Huang, Han-Chen; Tsai, Yao-Hsu; Huang, Shih-Hsiang

    2015-01-01

    In order to help students absorb knowledge, schools often conduct reading activities. Thorough planning and strategies, however, are needed to insure the effect of reading promotions, and make them a deeply-rooted part of life. This study adopted the analytic hierarchy process (AHP) to discuss the relevant factors in promoting reading activities…

  14. Factors Influencing Active Learning in Small Enterprises. Working Paper.

    ERIC Educational Resources Information Center

    Hawke, Geof

    The factors influencing active learning in small enterprises were examined. Data from earlier Australian studies were examined in an attempt to provide a framework that might inform the relationship between educational systems and small enterprises. Special attention was paid to a 1988 study of systematic differences between small businesses that…

  15. Heat shock factor 2 is activated during mouse heart development.

    PubMed

    Eriksson, M; Jokinen, E; Sistonen, L; Leppä, S

    2000-08-01

    Two members of the heat shock transcription factor family, HSF1 and HSF2, have been identified as activators of mammalian heat shock gene expression. HSF1 acts as a classical stress-responsive factor, whereas HSF2 might play a role in embryogenesis, since it is active during pre- and post-implantation periods up to 15.5 days of mouse embryonic development. In this study, we analyzed HSF1 and HSF2 expression and activation during mouse heart formation. Our results show an abundant expression of HSF1 throughout heart development. In contrast, expression of the alternatively spliced HSF2-alpha and HSF2-beta, and an additional higher molecular weight isoform is strongly upregulated in the developing mouse heart at E11.5-12.5, a stage after which tubular heart has looped and chambers formed, and the myocardial walls are maturating and the valves differentiating. At the same developmental stage, HSF2 DNA-binding activity is transiently induced, whereas the weak HSE-binding activity, which is detected throughout heart development, consists primarily of HSF1. Interestingly, heat shock gene expression shows no temporal or spatial correlation with HSF2 expression and activation. Taken together, our results indicate that HSF2 activation is associated with specific stages of heart formation but is not involved in the regulation of inducible heat shock gene expression.

  16. Psychosocial Factors and Theory in Physical Activity Studies in Minorities

    PubMed Central

    Mama, Scherezade K.; McNeill, Lorna H.; McCurdy, Sheryl A.; Evans, Alexandra E.; Diamond, Pamela M.; Adamus-Leach, Heather J.; Lee, Rebecca E.

    2015-01-01

    Objectives To summarize the effectiveness of interventions targeting psychosocial factors to increase physical activity (PA) among ethnic minority adults and explore theory use in PA interventions. Methods Studies (N = 11) were identified through a systematic review and targeted African American/Hispanic adults, specific psychosocial factors, and PA. Data were extracted using a standard code sheet and the Theory Coding Scheme. Results Social support was the most common psychosocial factor reported, followed by motivational readiness, and self-efficacy, as being associated with increased PA. Only 7 studies explicitly reported using a theoretical framework. Conclusions Future efforts should explore theory use in PA interventions and how integration of theoretical constructs, including psychosocial factors, increases PA. PMID:25290599

  17. Mediation of mouse natural cytotoxic activity by tumour necrosis factor

    NASA Astrophysics Data System (ADS)

    Ortaldo, John R.; Mason, Llewellyn H.; Mathieson, Bonnie J.; Liang, Shu-Mei; Flick, David A.; Herberman, Ronald B.

    1986-06-01

    Natural cell-mediated cytotoxic activity in the mouse has been associated with two types of effector cells, the natural killer (NK) cell and the natural cytotoxic (NC) cell, which seem to differ with regard to their patterns of target selectivity, cell surface characteristics and susceptibility to regulatory factors1. During studies on the mechanism of action of cytotoxic molecules, it became evident that WEHI-164, the prototype NC target cell, was highly susceptible to direct lysis by both human and mouse recombinant tumour necrosis factor (TNF). Here we show that NC, but not NK activity mediated by normal splenocytes, is abrogated by rabbit antibodies to recombinant and natural TNF, respectively. Thus, the cell-mediated activity defined as NC is due to release of TNF by normal spleen cells and does not represent a unique natural effector mechanism.

  18. Relationship between short activated partial thromboplastin times, thrombin generation, procoagulant factors and procoagulant phospholipid activity.

    PubMed

    Mina, Ashraf; Favaloro, Emmanuel J; Koutts, Jerry

    2012-04-01

    Short activated partial thromboplastin times (APTTs) are associated with thrombosis. However, what short APTTs actually represent in terms of possible mechanistic pathways is not well characterized. We have assessed thrombin generation as compared with levels of procoagulant factor (fibrinogen, V, VIII, IX, XI and XII) activities, von Willebrand factor level and activity using collagen binding, as well as procoagulant phospholipid activity, in 113 consecutive samples exhibiting a short APTT compared with an equal number of age-matched and sex-matched samples yielding a normal APTT. We found a significant difference in peak thrombin generation, velocity index and area under the curve between the two groups, and that thrombin generation markers correlated with the APTT, procoagulant phospholipid activity and several procoagulant clotting factors. We conclude that short APTTs represent a procoagulant milieu, as represented by heightened thrombin generation and several other heightened procoagulant activities, which may help explain the association with thrombosis.

  19. LPS-inducible factor(s) from activated macrophages mediates cytolysis of Naegleria fowleri amoebae

    SciTech Connect

    Cleary, S.F.; Marciano-Cabral, F.

    1986-03-01

    Soluble cytolytic factors of macrophage origin have previously been described with respect to their tumoricidal activity. The purpose of this study was to investigate the mechanism and possible factor(s) responsible for cytolysis of the amoeba Naegleria fowleri by activated peritoneal macrophages from B6C3F1 mice. Macrophages or conditioned medium (CM) from macrophage cultures were incubated with /sup 3/H-Uridine labeled amoebae. Percent specific release of label served as an index of cytolysis. Bacille Calmette-Guerin (BCG) and Corynebacterium parvum macrophages demonstrated significant cytolysis of amoebae at 24 h with an effector to target ratio of 10:1. Treatment of macrophages with inhibitors of RNA or protein synthesis blocked amoebicidal activity. Interposition of a 1 ..mu..m pore membrane between macrophages and amoebae inhibited killing. Inhibition in the presence of the membrane was overcome by stimulating the macrophages with LPS. CM from SPS-stimulated, but not unstimulated, cultures of activated macrophages was cytotoxic for amoebae. The activity was heat sensitive and was recovered from ammonium sulfate precipitation of the CM. Results indicate that amoebicidal activity is mediated by a protein(s) of macrophage origin induced by target cell contact or stimulation with LPS.

  20. Hepatocyte tissue factor activates the coagulation cascade in mice

    PubMed Central

    Sullivan, Bradley P.; Kopec, Anna K.; Joshi, Nikita; Cline, Holly; Brown, Juliette A.; Bishop, Stephanie C.; Kassel, Karen M.; Rockwell, Cheryl; Mackman, Nigel

    2013-01-01

    In this study, we characterized tissue factor (TF) expression in mouse hepatocytes (HPCs) and evaluated its role in mouse models of HPC transplantation and acetaminophen (APAP) overdose. TF expression was significantly reduced in isolated HPCs and liver homogenates from TFflox/flox/albumin-Cre mice (HPCΔTF mice) compared with TFflox/flox mice (control mice). Isolated mouse HPCs expressed low levels of TF that clotted factor VII-deficient human plasma. In addition, HPC TF initiated factor Xa generation without exogenous factor VIIa, and TF activity was increased dramatically after cell lysis. Treatment of HPCs with an inhibitory TF antibody or a cell-impermeable lysine-conjugating reagent prior to lysis substantially reduced TF activity, suggesting that TF was mainly present on the cell surface. Thrombin generation was dramatically reduced in APAP-treated HPCΔTF mice compared with APAP-treated control mice. In addition, thrombin generation was dependent on donor HPC TF expression in a model of HPC transplantation. These results suggest that mouse HPCs constitutively express cell surface TF that mediates activation of coagulation during hepatocellular injury. PMID:23305736

  1. Spotlight on blisibimod and its potential in the treatment of systemic lupus erythematosus: evidence to date

    PubMed Central

    Lenert, Aleksander; Niewold, Timothy B; Lenert, Petar

    2017-01-01

    B cells in general and BAFF (B cell activating factor of the tumor necrosis factor [TNF] family) in particular have been primary targets of recent clinical trials in systemic lupus erythematosus (SLE). In 2011, belimumab, a monoclonal antibody against BAFF, became the first biologic agent approved for the treatment of SLE. Follow-up studies have shown excellent long-term safety and tolerability of belimumab. In this review, we critically analyze blisibimod, a novel BAFF-neutralizing agent. In contrast to belimumab that only blocks soluble BAFF trimer but not soluble 60-mer or membrane BAFF, blisibimod blocks with high affinity all three forms of BAFF. Furthermore, blisibimod has a unique structure built on four high-affinity BAFF-binding peptides fused to the IgG1-Fc carrier. It was tested in phase I and II trials in SLE where it showed safety and tolerability. While it failed to reach the primary endpoint in a recent phase II trial, post hoc analysis demonstrated its efficacy in SLE patients with higher disease activity. Based on these results, blisibimod is currently undergoing phase III trials targeting this responder subpopulation of SLE patients. The advantage of blisibimod, compared to its competitors, lies in its higher avidity for BAFF, but a possible drawback may come from its immunogenic potential and the anticipated loss of efficacy over time. PMID:28331294

  2. Factors related to physical activity: a study of adolescents.

    PubMed

    Vilhjalmsson, R; Thorlindsson, T

    1998-09-01

    Although the consequences of physical activity have been carefully documented, less is known about its correlates, particularly among children and youth. Based on a representative national survey of 1131 Icelandic adolescents, the study examined various physical, psychological, social and demographic factors related to physical activity. Male sex, significant others' involvement in physical activity (father, friend and older brother), sociability, perceived importance of sport and of health improvement and satisfaction with mandatory gym classes in school, were all related to more involvement, whereas hours of paid work and TV-viewing were related to less. Furthermore, the data suggested that the influence of friend's participation in physical activity depends on his or her emotional significance. Influential others appeared to affect males and females in the same way. The meaning of the results and their implications for future research are discussed.

  3. Role of the kidney in the expression of low molecular weight factors with growth factor activity.

    PubMed

    Jacob, C; Maachi, F; el Farricha, O; Dousset, B; Kessler, M; Belleville, F; Nabet, P

    1993-06-01

    Small molecules of peptidic nature, called low molecular weight growth factors (LMW-GF < 1000 Da) are present in normal human serum ultrafiltrate. They enhance the somatomedin activity as measured by the incorporation of 35SO4 into chick embryo cartilages. On the basis of this in vitro test, LMW-GF activities were measured in serum ultrafiltrates of hemodialyzed patients and renal transplant recipients during the post-transplantation follow-up. LMW-GF activity was always zero in patients with chronic renal failure. It was checked that these results were not due to the presence of low molecular weight somatomedin inhibitors or to the increased sulfate concentration. After successful renal transplantation, the LMW-GF activity of patients ultrafiltrates returned to normal at the same time or before the improvement of renal function. In case of post-transplant complications, a decrease in LMW-GF activity accompanied or even occurred prior to impairment of renal function. In functioning graft, LMW-GF activity reappears rapidly, whereas its normalization is delayed in case of tubular nephropathy or episode of acute rejection. It was suggested that the kidney is involved in LMW-GF molecules production or processing. It could be speculated that LMW-GF activity might be a prognostic factor in renal transplantation.

  4. Macrophage Migration Inhibitory Factor Activates Hypoxia-Inducible Factor in a p53-Dependent Manner

    PubMed Central

    Oda, Seiko; Oda, Tomoyuki; Nishi, Kenichiro; Takabuchi, Satoshi; Wakamatsu, Takuhiko; Tanaka, Tomoharu; Adachi, Takehiko; Fukuda, Kazuhiko; Semenza, Gregg L.; Hirota, Kiichi

    2008-01-01

    Background Macrophage migration inhibitory factor (MIF) is not only a cytokine which has a critical role in several inflammatory conditions but also has endocrine and enzymatic functions. MIF is identified as an intracellular signaling molecule and is implicated in the process of tumor progression, and also strongly enhances neovascularization. Overexpression of MIF has been observed in tumors from various organs. MIF is one of the genes induced by hypoxia in an hypoxia-inducible factor 1 (HIF-1)-dependent manner. Methods/Principal Findings The effect of MIF on HIF-1 activity was investigated in human breast cancer MCF-7 and MDA-MB-231 cells, and osteosarcoma Saos-2 cells. We demonstrate that intracellular overexpression or extracellular administration of MIF enhances activation of HIF-1 under hypoxic conditions in MCF-7 cells. Mutagenesis analysis of MIF and knockdown of 53 demonstrates that the activation is not dependent on redox activity of MIF but on wild-type p53. We also indicate that the MIF receptor CD74 is involved in HIF-1 activation by MIF at least when MIF is administrated extracellularly. Conclusion/Significance MIF regulates HIF-1 activity in a p53-dependent manner. In addition to MIF's potent effects on the immune system, MIF is linked to fundamental processes conferring cell proliferation, cell survival, angiogenesis, and tumor invasiveness. This functional interdependence between MIF and HIF-1α protein stabilization and transactivation activity provide a molecular mechanism for promotion of tumorigenesis by MIF. PMID:18493321

  5. Reliable and Affordable Control Systems Active Combustor Pattern Factor Control

    NASA Technical Reports Server (NTRS)

    McCarty, Bob; Tomondi, Chris; McGinley, Ray

    2004-01-01

    Active, closed-loop control of combustor pattern factor is a cooperative effort between Honeywell (formerly AlliedSignal) Engines and Systems and the NASA Glenn Research Center to reduce emissions and turbine-stator vane temperature variations, thereby enhancing engine performance and life, and reducing direct operating costs. Total fuel flow supplied to the engine is established by the speed/power control, but the distribution to individual atomizers will be controlled by the Active Combustor Pattern Factor Control (ACPFC). This system consist of three major components: multiple, thin-film sensors located on the turbine-stator vanes; fuel-flow modulators for individual atomizers; and control logic and algorithms within the electronic control.

  6. Factors affecting farm noise during common agricultural activities.

    PubMed

    Franklin, R C; Depczynski, J; Challinor, K; Williams, W; Fragar, L J

    2006-05-01

    Hearing injury due to exposure to excessive noise during common farming activities is a significant problem for farmers. The aim of this study was to investigate factors that affect the level of risk to hearing caused by common farming activities. Noise levels on farms were measured across a range of activities and producer groups, and situational factors that effect noise levels were also investigated. Older tractors were found to be 6 dB louder than newer tractors. Cabs reduced noise to the operator by 16 dB, which was halved to 8 dB if a door was open. Radios added between 3 and 5 dB to the noise in the cab. These variables significantly affect the noise level at the ear of operators and others in the workplace, and affect the subsequent exposure limits that are considered safe. Situational factors need to be considered in assessing the level of risk to farmers' hearing and in choosing noise management strategies on the farm. This information has been incorporated into material about hearing and discussions with farmers who participated in field day hearing screening programs in Australia.

  7. Stellar Activity and CMEs: Important Factors of Planetary Evolution

    NASA Astrophysics Data System (ADS)

    Khodachenko, Maxim L.

    CME activity of the Sun is known to be an important impacting factor for the magnetospheres, atmospheres, and surfaces of solar system planets. Following an idea of a solar-stellar analogy, CME phenomena are expected on other stars as well. The main planetary impact factors of the stellar CMEs include the associated interplanetary shocks, plasma density and velocity disturbances, energetic particles accelerated in the shock regions, as well as distortions of the magnetic field direction and modulus. All these factors should be properly taken into account during the study of evolutionary processes on exoplanets and their atmospheric and plasma environments. The planetary impact of the stellar CME activity may vary depending on stellar age, stellar spectral type and the orbital distance of a planet. Because of the relatively short range of propagation of the majority of CMEs, they affect most strongly the magnetospheres and atmospheres of close-orbit ( < 0.1 AU) exoplanets. In this chapter we discuss an issue of the stellar CME activity in the context of several actual problems of modern exoplanetology, including planetary atmosphere mass loss, planet survival at close orbits, and definition of a criterion for habitability.

  8. Activating transcription factor 6 derepression mediates neuroprotection in Huntington disease.

    PubMed

    Naranjo, José R; Zhang, Hongyu; Villar, Diego; González, Paz; Dopazo, Xose M; Morón-Oset, Javier; Higueras, Elena; Oliveros, Juan C; Arrabal, María D; Prieto, Angela; Cercós, Pilar; González, Teresa; De la Cruz, Alicia; Casado-Vela, Juan; Rábano, Alberto; Valenzuela, Carmen; Gutierrez-Rodriguez, Marta; Li, Jia-Yi; Mellström, Britt

    2016-02-01

    Deregulated protein and Ca2+ homeostasis underlie synaptic dysfunction and neurodegeneration in Huntington disease (HD); however, the factors that disrupt homeostasis are not fully understood. Here, we determined that expression of downstream regulatory element antagonist modulator (DREAM), a multifunctional Ca2+-binding protein, is reduced in murine in vivo and in vitro HD models and in HD patients. DREAM downregulation was observed early after birth and was associated with endogenous neuroprotection. In the R6/2 mouse HD model, induced DREAM haplodeficiency or blockade of DREAM activity by chronic administration of the drug repaglinide delayed onset of motor dysfunction, reduced striatal atrophy, and prolonged life span. DREAM-related neuroprotection was linked to an interaction between DREAM and the unfolded protein response (UPR) sensor activating transcription factor 6 (ATF6). Repaglinide blocked this interaction and enhanced ATF6 processing and nuclear accumulation of transcriptionally active ATF6, improving prosurvival UPR function in striatal neurons. Together, our results identify a role for DREAM silencing in the activation of ATF6 signaling, which promotes early neuroprotection in HD.

  9. Activating transcription factor 6 derepression mediates neuroprotection in Huntington disease

    PubMed Central

    Naranjo, José R.; Zhang, Hongyu; Villar, Diego; González, Paz; Dopazo, Xose M.; Morón-Oset, Javier; Higueras, Elena; Oliveros, Juan C.; Arrabal, María D.; Prieto, Angela; Cercós, Pilar; González, Teresa; De la Cruz, Alicia; Casado-Vela, Juan; Rábano, Alberto; Valenzuela, Carmen; Gutierrez-Rodriguez, Marta; Li, Jia-Yi; Mellström, Britt

    2016-01-01

    Deregulated protein and Ca2+ homeostasis underlie synaptic dysfunction and neurodegeneration in Huntington disease (HD); however, the factors that disrupt homeostasis are not fully understood. Here, we determined that expression of downstream regulatory element antagonist modulator (DREAM), a multifunctional Ca2+-binding protein, is reduced in murine in vivo and in vitro HD models and in HD patients. DREAM downregulation was observed early after birth and was associated with endogenous neuroprotection. In the R6/2 mouse HD model, induced DREAM haplodeficiency or blockade of DREAM activity by chronic administration of the drug repaglinide delayed onset of motor dysfunction, reduced striatal atrophy, and prolonged life span. DREAM-related neuroprotection was linked to an interaction between DREAM and the unfolded protein response (UPR) sensor activating transcription factor 6 (ATF6). Repaglinide blocked this interaction and enhanced ATF6 processing and nuclear accumulation of transcriptionally active ATF6, improving prosurvival UPR function in striatal neurons. Together, our results identify a role for DREAM silencing in the activation of ATF6 signaling, which promotes early neuroprotection in HD. PMID:26752648

  10. Macrophage migration inhibitory factor (MIF) enzymatic activity and lung cancer.

    PubMed

    Mawhinney, Leona; Armstrong, Michelle E; O' Reilly, Ciaran; Bucala, Richard; Leng, Lin; Fingerle-Rowson, Gunter; Fayne, Darren; Keane, Michael P; Tynan, Aisling; Maher, Lewena; Cooke, Gordon; Lloyd, David; Conroy, Helen; Donnelly, Seamas C

    2015-04-16

    The cytokine macrophage migration inhibitory factor (MIF) possesses unique tautomerase enzymatic activity, which contributes to the biological functional activity of MIF. In this study, we investigated the effects of blocking the hydrophobic active site of the tautomerase activity of MIF in the pathogenesis of lung cancer. To address this, we initially established a Lewis lung carcinoma (LLC) murine model in Mif-KO and wild-type (WT) mice and compared tumor growth in a knock-in mouse model expressing a mutant MIF lacking enzymatic activity (Mif (P1G)). Primary tumor growth was significantly attenuated in both Mif-KO and Mif (P1G) mice compared with WT mice. We subsequently undertook a structure-based, virtual screen to identify putative small molecular weight inhibitors specific for the tautomerase enzymatic active site of MIF. From primary and secondary screens, the inhibitor SCD-19 was identified, which significantly attenuated the tautomerase enzymatic activity of MIF in vitro and in biological functional screens. In the LLC murine model, SCD-19, given intraperitoneally at the time of tumor inoculation, was found to significantly reduce primary tumor volume by 90% (p < 0.001) compared with the control treatment. To better replicate the human disease scenario, SCD-19 was given when the tumor was palpable (at d 7 after tumor inoculation) and, again, treatment was found to significantly reduce tumor volume by 81% (p < 0.001) compared with the control treatment. In this report, we identify a novel inhibitor that blocks the hydrophobic pocket of MIF, which houses its specific tautomerase enzymatic activity, and demonstrate that targeting this unique active site significantly attenuates lung cancer growth in in vitro and in vivo systems.

  11. Laterality of Brain Activation for Risk Factors of Addiction

    PubMed Central

    Gordon, Harold W.

    2015-01-01

    Background Laterality of brain activation is reported for tests of risk factors of addiction—impulsivity and craving—but authors rarely address the potential significance of those asymmetries. Objective The purpose of this study is to demonstrate this laterality and discuss its relevance to cognitive and neurophysiological asymmetries associated with drug abuse vulnerability in order to provide new insights for future research in drug abuse. Method From published reports, brain areas of activation for two tests of response inhibition or craving for drugs of abuse were compiled from fMRI activation peaks were tabulated for eight sections (octants) in each hemisphere. Percent asymmetries were calculated (R−L/R+L) across studies for each area. Results For impulsivity, most activation peaks favored the right hemisphere. Overall, the percent difference was 32% (Χ2 = 16.026; p < .0001) with the greater asymmetry for anterior peaks (46.8%; Χ2 = 17.329; p < .0001). The asymmetries for cue-induced craving were opposite, favoring the left hemisphere by 6.7% (Χ2 = 4.028; p < .05). The consistency of left asymmetry was found for almost all drugs. For nicotine, studies where subjects were not allowed to smoke (deprived) prior to measurement had the same left hemisphere activation but those who smoked (satiated) before the fMRI measure showed right asymmetry. Conclusions Brain activation studies demonstrate different left/right hemispheric contributions for impulsivity versus craving—factors related to addiction. Failure to take laterality into consideration is a missed opportunity in designing studies and gaining insight into the etiology of drug abuse and pathways for treatment. PMID:26674074

  12. Time-activity relationships to VOC personal exposure factors

    NASA Astrophysics Data System (ADS)

    Edwards, Rufus D.; Schweizer, Christian; Llacqua, Vito; Lai, Hak Kan; Jantunen, Matti; Bayer-Oglesby, Lucy; Künzli, Nino

    Social and demographic factors have been found to play a significant role in differences between time-activity patterns of population subgroups. Since time-activity patterns largely influence personal exposure to compounds as individuals move across microenvironments, exposure subgroups within the population may be defined by factors that influence daily activity patterns. Socio-demographic and environmental factors that define time-activity subgroups also define quantifiable differences in VOC personal exposures to different sources and individual compounds in the Expolis study. Significant differences in exposures to traffic-related compounds ethylbenzene, m- and p-xylene and o-xylene were observed in relation to gender, number of children and living alone. Categorization of exposures further indicated time exposed to traffic at work and time in a car as important determinants. Increased exposures to decane, nonane and undecane were observed for males, housewives and self-employed. Categorization of exposures indicated exposure subgroups related to workshop use and living downtown. Higher exposures to 3-carene and α-pinene commonly found in household cleaning products and fragrances were associated with more children, while exposures to traffic compounds ethylbenzene, m- and p-xylene and o-xylene were reduced with more children. Considerable unexplained variation remained in categorization of exposures associated with home product use and fragrances, due to individual behavior and product choice. More targeted data collection methods in VOC exposure studies for these sources should be used. Living alone was associated with decreased exposures to 2-methyl-1-propanol and 1-butanol, and traffic-related compounds. Identification of these subgroups may help to reduce the large amount of unexplained variation in VOC exposure studies. Further they may help in assessing impacts of urban planning that result in changes in behavior of individuals, resulting in shifts in

  13. Angiotensin II activates the proinflammatory transcription factor nuclear factor-kappaB in human monocytes.

    PubMed

    Kranzhöfer, R; Browatzki, M; Schmidt, J; Kübler, W

    1999-04-21

    The renin-angiotensin system may contribute to the pathogenesis of atherosclerosis. A common feature of all stages of atherosclerosis is inflammation of the vessel wall. The transcription factor nuclear factor-kappaB (NF-kappaB) participates in most signaling pathways involved in inflammation. This study therefore examined the effect of angiotensin (ANG) II on NF-kappaB activation in monocytic cells, a major cellular component of human atheroma, by electrophoretic mobility shift assay. ANG II, like TNFalpha, caused rapid activation of NF-kappaB in human mononuclear cells isolated from peripheral blood by Ficoll density gradient. This ANG II effect was blocked by the angiotensin AT1 receptor antagonist losartan. Specificity of ANG II-induced NF-kappaB activation was ascertained by supershift and competition experiments. Moreover, ANG II stimulated NF-kappaB activation in human monocytes, but not in lymphocytes from the same preparation. Together, the data demonstrate the ability of the vasoactive peptide ANG II to activate inflammatory pathways in human monocytes.

  14. Inhibition of the activation of Hageman factor (factor XII) by complement subcomponent C1q.

    PubMed

    Rehmus, E H; Greene, B M; Everson, B A; Ratnoff, O D

    1987-08-01

    Hageman factor (HF, Factor XII) is activated by glass, collagen, and ellagic acid, and initiates blood coagulation via the intrinsic pathway. C1q inhibits collagen-induced platelet aggregation and adherence of platelets to glass, effects attributable to the collagen-like region of C1q. We examined the actions of C1q on HF activation. Incubation of C1q with HF before addition of HF-deficient plasma extended the activated partial thromboplastin time. Similarly, when glass tubes were coated with C1q before testing, the partial thromboplastin time of normal plasma was increased. C1q reduced the activation of HF by ellagic acid, as measured by the release of p-nitroaniline from the synthetic substrate H-D-prolyl-L-phenylalanyl-L-arginine-p-nitroanilide dihydrochloride, an effect inhibited by monoclonal anti-human C1q murine IgG and by digestion of C1q by collagenase. Thus, C1q inhibits activation of HF in vitro in clot-promoting and amidolytic assays and suggests a regulatory mechanism for the inhibition of coagulation.

  15. Inhibition of the activation of Hageman factor (factor XII) by complement subcomponent C1q.

    PubMed Central

    Rehmus, E H; Greene, B M; Everson, B A; Ratnoff, O D

    1987-01-01

    Hageman factor (HF, Factor XII) is activated by glass, collagen, and ellagic acid, and initiates blood coagulation via the intrinsic pathway. C1q inhibits collagen-induced platelet aggregation and adherence of platelets to glass, effects attributable to the collagen-like region of C1q. We examined the actions of C1q on HF activation. Incubation of C1q with HF before addition of HF-deficient plasma extended the activated partial thromboplastin time. Similarly, when glass tubes were coated with C1q before testing, the partial thromboplastin time of normal plasma was increased. C1q reduced the activation of HF by ellagic acid, as measured by the release of p-nitroaniline from the synthetic substrate H-D-prolyl-L-phenylalanyl-L-arginine-p-nitroanilide dihydrochloride, an effect inhibited by monoclonal anti-human C1q murine IgG and by digestion of C1q by collagenase. Thus, C1q inhibits activation of HF in vitro in clot-promoting and amidolytic assays and suggests a regulatory mechanism for the inhibition of coagulation. PMID:3038961

  16. Significantly different coagulation factor activities underlying the variability of 'normal' activated partial thromboplastin time.

    PubMed

    Park, Kyoung-Jin; Kwon, Eui-Hoon; Ma, Youngeun; Park, In-Ae; Kim, Seon-Woo; Kim, Sun-Hee; Kim, Hee-Jin

    2012-01-01

    The activated partial thromboplastin time (aPTT) is a widely used coagulation screening test in routine laboratories. The aPTT level in the control population varies and is reflected by the reference interval. However, there have been no studies to investigate the coagulation status determining the variability of the aPTT. The aim of this study was to investigate the coagulation factor activities underlying the variability of aPTT in the population. The study participants were reference individuals with prothrombin time and aPTT within reference intervals. The aPTT was determined using STA-PTT Automate (Diagnostica Stago, Asnieres, France; local reference interval, 29.1-41.9 s). Those with aPTT within the marginal ranges of reference interval were selected for factor assays. We defined the lower marginal group as the lowest 10 percentile of reference interval (29.1-30.9 s) and the upper marginal group as the highest 10 percentile (38.0-41.9 s). Activities of factor II, V, VIII, IX, X, XI, and XII were determined in both groups. The lower marginal and upper marginal groups consisted of 220 and 209 individuals, respectively. All coagulation factors were significantly higher in the lower marginal than in the upper marginal group (P = 0.0127 for factor II and P < 0.0001 for the others). Multiple logistic regression analyses revealed factor XII and VIII were two strongest contributors determining the aPTT level, whereas factor XI was not significantly different between the groups (P = 0.095). This study firstly demonstrated significantly different coagulation factor activities underlying the variability of aPTT in reference individuals. The results suggested the possibility of disease association or phenotypic contribution of variable coagulation activities in the population.

  17. Absence of in vitro Procoagulant Activity in Immunoglobulin Preparations due to Activated Coagulation Factors

    PubMed Central

    Oviedo, Adriana E.; Bernardi, María E.; Guglielmone, Hugo A.; Vitali, María S.

    2015-01-01

    Summary Background Immunoglobulin (IG) products, including intravenous (IVIG) or subcutaneous (SCIG) immunoglobulins are considered safe and effective for medical therapy; however, a sudden and unexpected increase in thromboembolic events (TE) after administration of certain batches of IVIG products has been attributed to the presence of activated coagulation factors, mainly factor XIa. Our aims were to examine the presence of enduring procoagulant activity during the manufacturing process of IGs, with special focus on monitoring factor XIa, and to evaluate the presence of in vitro procoagulant activity attributed to coagulation factors in different lots of IVIG and SCIG. Methods Samples of different steps of IG purification, 19 lots of IVIG and 9 of SCIG were analyzed and compared with 1 commercial preparation of IVIG and 2 of SCIG, respectively. Factors II, VII, IX, XI and XIa and non-activated partial thromboplastin time (NAPTT) were assayed. Results The levels of factors II, VII, IX, X and XI were non-quantifiable once fraction II had been re-dissolved and in all analyzed lots of IVIG and SCIG. The level of factor XIa at that point was under the detection limits of the assay, and NAPTT yielded values greater than the control during the purification process. In SCIG, we detected higher concentrations of factor XIa in the commercial products, which reached values up to 5 times higher than the average amounts found in the 9 batches produced by UNC-Hemoderivados. Factor XIa in commercial IVIG reached levels slightly higher than those of the 19 batches produced by UNC-Hemoderivados. Conclusion IVIG and SCIG manufactured by UNC-Hemoderivados showed a lack of thrombogenic potential, as demonstrated not only by the laboratory data obtained in this study but also by the absence of any reports of TE registered by the post marketing pharmacovigilance department. PMID:26733772

  18. Nuclear Factor of Activated T Cells Transcription Factor Nfatp Controls Superantigen-Induced Lethal Shock

    PubMed Central

    Tsytsykova, Alla V.; Goldfeld, Anne E.

    2000-01-01

    Tumor necrosis factor α (TNF-α) is the key mediator of superantigen-induced T cell lethal shock. Here, we show that nuclear factor of activated T cells transcription factor, NFATp, controls susceptibility to superantigen-induced lethal shock in mice through its activation of TNF-α gene transcription. In NFATp-deficient mice, T cell stimulation leads to delayed induction and attenuation of TNF-α mRNA levels, decreased TNF-α serum levels, and resistance to superantigen-induced lethal shock. By contrast, after lipopolysaccharide (LPS) challenge, serum levels of TNF-α and susceptibility to shock are unaffected. These results demonstrate that NFATp is an essential activator of immediate early TNF-α gene expression in T cells and they present in vivo evidence of the inducer- and cell type–specific regulation of TNF-α gene expression. Furthermore, they suggest NFATp as a potential selective target in the treatment of superantigen-induced lethal shock. PMID:10952728

  19. Transcription Factor Arabidopsis Activating Factor1 Integrates Carbon Starvation Responses with Trehalose Metabolism.

    PubMed

    Garapati, Prashanth; Feil, Regina; Lunn, John Edward; Van Dijck, Patrick; Balazadeh, Salma; Mueller-Roeber, Bernd

    2015-09-01

    Plants respond to low carbon supply by massive reprogramming of the transcriptome and metabolome. We show here that the carbon starvation-induced NAC (for NO APICAL MERISTEM/ARABIDOPSIS TRANSCRIPTION ACTIVATION FACTOR/CUP-SHAPED COTYLEDON) transcription factor Arabidopsis (Arabidopsis thaliana) Transcription Activation Factor1 (ATAF1) plays an important role in this physiological process. We identified TREHALASE1, the only trehalase-encoding gene in Arabidopsis, as a direct downstream target of ATAF1. Overexpression of ATAF1 activates TREHALASE1 expression and leads to reduced trehalose-6-phosphate levels and a sugar starvation metabolome. In accordance with changes in expression of starch biosynthesis- and breakdown-related genes, starch levels are generally reduced in ATAF1 overexpressors but elevated in ataf1 knockout plants. At the global transcriptome level, genes affected by ATAF1 are broadly associated with energy and carbon starvation responses. Furthermore, transcriptional responses triggered by ATAF1 largely overlap with expression patterns observed in plants starved for carbon or energy supply. Collectively, our data highlight the existence of a positively acting feedforward loop between ATAF1 expression, which is induced by carbon starvation, and the depletion of cellular carbon/energy pools that is triggered by the transcriptional regulation of downstream gene regulatory networks by ATAF1.

  20. Activated Complement Factors as Disease Markers for Sepsis

    PubMed Central

    Charchaflieh, Jean; Rushbrook, Julie; Worah, Samrat; Zhang, Ming

    2015-01-01

    Sepsis is a leading cause of death in the United States and worldwide. Early recognition and effective management are essential for improved outcome. However, early recognition is impeded by lack of clinically utilized biomarkers. Complement factors play important roles in the mechanisms leading to sepsis and can potentially serve as early markers of sepsis and of sepsis severity and outcome. This review provides a synopsis of recent animal and clinical studies of the role of complement factors in sepsis development, together with their potential as disease markers. In addition, new results from our laboratory are presented regarding the involvement of the complement factor, mannose-binding lectin, in septic shock patients. Future clinical studies are needed to obtain the complete profiles of complement factors/their activated products during the course of sepsis development. We anticipate that the results of these studies will lead to a multipanel set of sepsis biomarkers which, along with currently used laboratory tests, will facilitate earlier diagnosis, timely treatment, and improved outcome. PMID:26420913

  1. Activation of the neutrophil bactericidal activity for nontypable Haemophilus influenzae by tumor necrosis factor and lymphotoxin.

    PubMed

    Tan, A M; Ferrante, A; Goh, D H; Roberton, D M; Cripps, A W

    1995-02-01

    Previous studies have suggested that, in vivo, activated T lymphocytes and neutrophils are important in immunity to nontypable Haemophilus influenzae. We now extend this work by showing that neutrophils pretreated with products of activated T lymphocytes or activated macrophages show significantly enhanced killing of nontypable H. influenzae. Lymphotoxin, a product of activated T lymphocytes, significantly enhanced the neutrophil-mediated killing of nontypable H. influenzae, and tumor necrosis factor, produced by activated T lymphocytes as well as macrophages stimulated by activated T lymphocytes, also significantly increased the bactericidal activity of neutrophils. These cytokine-induced effects were seen with short pretreatment times of neutrophils and were maximal by 30 min. The killing of H. influenzae by neutrophils required the presence of heat-labile opsonins. In the absence of these opsonins, both tumor necrosis factor and lymphotoxin were unable to promote the killing of the bacteria by neutrophils. Furthermore, the results showed that tumor necrosis factor-primed neutrophils displayed significantly increased expression of CR3 and CR4 that was associated with increased phagocytosis of complement-opsonized nontypable H. influenzae. These cytokines may play an important role in immunity toward nontypable H. influenzae by stimulating neutrophil bactericidal activity.

  2. 75 FR 62634 - Proposed Information Collection (Obligation to Report Factors Affecting Entitlement) Activity...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-12

    ... AFFAIRS Proposed Information Collection (Obligation to Report Factors Affecting Entitlement) Activity... techniques or the use of other forms of information technology. Title: Obligation to Report Factors Affecting... entitlement factors. Individual factors such as income, marital status, and the beneficiary's number...

  3. 78 FR 46418 - Proposed Information Collection (Obligation To Report Factors Affecting Entitlement) Activity...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-31

    ... AFFAIRS Proposed Information Collection (Obligation To Report Factors Affecting Entitlement) Activity... techniques or the use of other forms of information technology. Title: Obligation to Report Factors Affecting... entitlement factors. Individual factors such as income, marital status, and the beneficiary's number...

  4. Rural children active trachoma risk factors and their interactions

    PubMed Central

    Muluneh, Essey Kebede; Zewotir, Temesgen; Bekele, Zerihun

    2016-01-01

    Introduction Trachoma is a serious public health problem in rural Ethiopia. The aim of this investigation was to provide in-depth statistical analysis of the risk factors associated with active trachoma among children of age 1-9 years of Kedida Gamela district, in Ethiopia. Methods A community based cross-sectional survey of trachoma was conducted in six selected rural kebeles of Kedida Gamela district, in Ethiopia from June 10-25, 2014. A total of 377 children (ages 1-9 years) were included in the study using two stage cluster sampling. All children were examined for trachoma by nurse data collectors supervised by ophthalmic supervisors using the WHO simplified clinical grading system. Ordinal survey logistic regression model was used to identify risk factors. Data analysis was done using SAS version 9.3. Results The best fit proportional odds model was identified to be the main effects and two-way and three-way interactios. Keeping cattle in the house was found to have a protective effect (OR=0.138, p-value=0.0003). The household wealth will have a more protective effect if the child attends school. Washing face with soap and water once a day has equivalent protective effect as washing face three-or-more times a day with water only. Conclusion The 2-way and 3-way significant interactions effects unfolded some of the controversies derived from similar studies on trachoma risk factors. The findings would suggest integrated effort to address two or three factors simultaneously is more fruitful than any novel intervention targeted to address a single risk factor. PMID:27642466

  5. Polyphosphate colocalizes with factor XII on platelet-bound fibrin and augments its plasminogen activator activity

    PubMed Central

    Lionikiene, Ausra S.; Georgiev, Georgi; Klemmer, Anja; Brain, Chelsea; Kim, Paul Y.

    2016-01-01

    Activated factor XII (FXIIa) has plasminogen activator capacity but its relative contribution to fibrinolysis is considered marginal compared with urokinase and tissue plasminogen activator. Polyphosphate (polyP) is released from activated platelets and mediates FXII activation. Here, we investigate the contribution of polyP to the plasminogen activator function of αFXIIa. We show that both polyP70, of the chain length found in platelets (60-100 mer), and platelet-derived polyP significantly augment the plasminogen activation capacity of αFXIIa. PolyP70 stimulated the autoactivation of FXII and subsequent plasminogen activation, indicating that once activated, αFXIIa remains bound to polyP70. Indeed, complex formation between polyP70 and αFXIIa provides protection against autodegradation. Plasminogen activation by βFXIIa was minimal and not enhanced by polyP70, highlighting the importance of the anion binding site. PolyP70 did not modulate plasmin activity but stimulated activation of Glu and Lys forms of plasminogen by αFXIIa. Accordingly, polyP70 was found to bind to FXII, αFXIIa, and plasminogen, but not βFXIIa. Fibrin and polyP70 acted synergistically to enhance αFXIIa-mediated plasminogen activation. The plasminogen activator activity of the αFXIIa-polyP70 complex was modulated by C1 inhibitor and histidine-rich glycoprotein, but not plasminogen activator inhibitors 1 and 2. Platelet polyP and FXII were found to colocalize on the activated platelet membrane in a fibrin-dependent manner and decorated fibrin strands extending from platelet aggregates. We show that in the presence of platelet polyP and the downstream substrate fibrin, αFXIIa is a highly efficient and favorable plasminogen activator. Our data are the first to document a profibrinolytic function of platelet polyP. PMID:27694320

  6. Nuclear factor Y regulates ancient budgerigar hepadnavirus core promoter activity.

    PubMed

    Shen, Zhongliang; Liu, Yanfeng; Luo, Mengjun; Wang, Wei; Liu, Jing; Liu, Wei; Pan, Shaokun; Xie, Youhua

    2016-09-16

    Endogenous viral elements (EVE) in animal genomes are the fossil records of ancient viruses and provide invaluable information on the origin and evolution of extant viruses. Extant hepadnaviruses include avihepadnaviruses of birds and orthohepadnaviruses of mammals. The core promoter (Cp) of hepadnaviruses is vital for viral gene expression and replication. We previously identified in the budgerigar genome two EVEs that contain the full-length genome of an ancient budgerigar hepadnavirus (eBHBV1 and eBHBV2). Here, we found eBHBV1 Cp and eBHBV2 Cp were active in several human and chicken cell lines. A region from nt -85 to -11 in eBHBV1 Cp was critical for the promoter activity. Bioinformatic analysis revealed a putative binding site of nuclear factor Y (NF-Y), a ubiquitous transcription factor, at nt -64 to -50 in eBHBV1 Cp. The NF-Y core binding site (ATTGG, nt -58 to -54) was essential for eBHBV1 Cp activity. The same results were obtained with eBHBV2 Cp and duck hepatitis B virus Cp. The subunit A of NF-Y (NF-YA) was recruited via the NF-Y core binding site to eBHBV1 Cp and upregulated the promoter activity. Finally, the NF-Y core binding site is conserved in the Cps of all the extant avihepadnaviruses but not of orthohepadnaviruses. Interestingly, a putative and functionally important NF-Y core binding site is located at nt -21 to -17 in the Cp of human hepatitis B virus. In conclusion, our findings have pinpointed an evolutionary conserved and functionally critical NF-Y binding element in the Cps of avihepadnaviruses.

  7. Endothelial cell activation induced by tumor necrosis factor and lymphotoxin.

    PubMed Central

    Cavender, D. E.; Edelbaum, D.; Ziff, M.

    1989-01-01

    Alterations in the morphology and histochemistry of vascular endothelial cells (EC) have been repeatedly observed at sites of chronic inflammation and immune reactions. These changes, which are most prominent in the EC postcapillary venules present in areas with large lymphocytic infiltrates, include the acquisition of a columnar or cuboidal morphology, the development of ribonuclease-sensitive metachromasia, and an increase in intracellular organelles. Thus, EC at sites of inflammation appear to be activated and to demonstrate increased metabolic activity. This study reports that both tumor necrosis factor-alpha (TNF) and lymphotoxin (LT) can activate cultured human umbilical vein EC, as measured by: 1) increased adhesiveness for lymphocytes, 2) increased cell metabolism, as measured by RNA and protein synthesis, and 3) increased cell volume. Although gamma interferon (IFN-gamma) and interleukin-1 (IL-1) have been shown previously to stimulate EC adhesiveness for lymphocytes, these two cytokines had only marginal effects on EC RNA and protein synthesis, and both caused a decrease in EC volume. These findings suggest that TNF and LT play a role in the type of activation of EC in vivo that leads to the development of tall endothelium and increased lymphocyte emigration. PMID:2466402

  8. Factors influencing dust exposure: finishing activities in drywall construction.

    PubMed

    Simmons, Catherine E; Jones, Rachael M; Boelter, Fred W

    2011-05-01

    Sanding drywall joint compound is a dusty construction activity. We studied potential factors influencing exposure to respirable and total dust for sanders and bystanders in the area of drywall joint compound finishing in 17 test events within a room-scale isolation chamber. We found the air change rate to be negatively correlated with dust C(twa) both in the sander's personal breathing zone and surrounding area. We could not conclude that sanding tool type systematically influences dust C(twa), but the use of 80-grit abrasive was associated with the highest dust C(twa). We found respirable dusts were uniformly dispersed 1-8.2 m from sanding activities at a fixed location. As anticipated, both respirable and total dust C(twa) in the sander's personal breathing zone are higher than in the surrounding area. The respirable fraction of the total dust mass C(twa) was greater in the surrounding area than in the sander's personal breathing zone. Respirable dust concentrations measured in real time increased over the duration of sanding, exhibiting a temporal trend that is similar to that predicted by the well-mixed box model with contaminant removal by mechanical ventilation only, and continuous emission. Dust concentrations returned to pre-activity (background) levels 2-4 hr after cessation of the sanding activity.

  9. Factor XI and contact activation as targets for antithrombotic therapy.

    PubMed

    Gailani, D; Bane, C E; Gruber, A

    2015-08-01

    The most commonly used anticoagulants produce therapeutic antithrombotic effects either by inhibiting thrombin or factor Xa (FXa) or by lowering the plasma levels of the precursors of these key enzymes, prothrombin and FX. These drugs do not distinguish between thrombin generation contributing to thrombosis from thrombin generation required for hemostasis. Thus, anticoagulants increase bleeding risk, and many patients who would benefit from therapy go untreated because of comorbidities that place them at unacceptable risk for hemorrhage. Studies in animals demonstrate that components of the plasma contact activation system contribute to experimentally induced thrombosis, despite playing little or no role in hemostasis. Attention has focused on FXII, the zymogen of a protease (FXIIa) that initiates contact activation when blood is exposed to foreign surfaces, and FXI, the zymogen of the protease FXIa, which links contact activation to the thrombin generation mechanism. In the case of FXI, epidemiologic data indicate this protein contributes to stroke and venous thromboembolism, and perhaps myocardial infarction, in humans. A phase 2 trial showing that reduction of FXI may be more effective than low molecular weight heparin at preventing venous thrombosis during knee replacement surgery provides proof of concept for the premise that an antithrombotic effect can be uncoupled from an anticoagulant effect in humans by targeting components of contact activation. Here, we review data on the role of FXI and FXII in thrombosis and results of preclinical and human trials for therapies targeting these proteins.

  10. [Regulation of myostatin promoter activity by myocyte enhancer factor 2].

    PubMed

    Li, Jia; Deng, Jie; Zhang, Junlin; Cheng, De; Wang, Huayan

    2012-08-01

    Myostatin (Mstn) is a member of the transforming growth factor-beta superfamily that functions as a negative regulator of skeletal muscle growth and differentiation in mammals. The transcriptional regulation of Mstn is controlled by multiple genes including MEF2, which raise the importance of identifying the binding sites of MEF2 on myostatin promoter region and mechanisms underlying. In this study, we investigated the transcriptional regulation of MEF2 on porcine Mstn promoter activity in C2C12 cells. Sequence analysis of the 1 969 bp porcine Mstn promoter region revealed that it contained three potential MEF2 motifs. Using a serial deletion strategy, we tested the activity of several promoter fragments by luciferase assay. Overexpression of MEF2C, but not MEF2A increased Mstn promoter activity in all the promoter fragments with MEF2 motifs by two to six folds, in both C2C12 myoblasts and myotubes. When we transfected exogenous MEF2C, Mstn mRNA level was also upregulated in C2C12 cells, but the protein level was only significantly increased in myotubes. Thus, we propose that MEF2C could modulate and restrain myogenesis by Mstn activation and Mstn-dependent gene processing in porcine. Our research also provided potential targets and an effective molecule to regulate Mstn expression and gave a new way to explore the functional performance of Mstn.

  11. Epidermal Platelet-activating Factor Receptor Activation and Ultraviolet B Radiation Result in Synergistic Tumor Necrosis Factor-alpha Production

    PubMed Central

    Wolverton, Jay E.; Al-Hassani, Mohammed; Yao, Yongxue; Zhang, Qiwei; Travers, Jeffrey B.

    2010-01-01

    Ultraviolet B radiation (UVB) is a potent stimulator of epidermal cytokine production which has been implicated in photoaggravated dermatoses. In addition to cytokines such as tumor necrosis factor-α (TNF-α), UVB generates bioactive lipids including platelet-activating factor (PAF). Our previous studies have demonstrated that UVB-mediated production of keratinocyte TNF-α is in part due to PAF. The current studies use a human PAF-receptor (PAF-R) negative epithelial cell line transduced with PAF-Rs and PAF–R-deficient mice to demonstrate that activation of the epidermal PAF-R along with UVB irradiation results in a synergistic production of TNF-α. It should be noted that PAF-R effects are mimicked by the protein kinase C (PKC) agonist phorbol myristic acetate, and are inhibited by pharmacological antagonists of the PKC gamma isoenzyme. These studies suggest that concomitant PAF-R activation and UVB irradiation results in a synergistic production of the cytokine TNF-α which is mediated in part via PKC. These studies provide a novel potential mechanism for photosensitivity responses. PMID:19769579

  12. The Transcription Factor p53 Influences Microglial Activation Phenotype

    PubMed Central

    Jayadev, Suman; Nesser, Nicole K.; Hopkins, Stephanie; Myers, Scott J.; Case, Amanda; Lee, Rona J.; Seaburg, Luke A.; Uo, Takuma; Murphy, Sean P.; Morrison, Richard S.; Garden, Gwenn A.

    2011-01-01

    Several neurodegenerative diseases are influenced by the innate immune response in the central nervous system (CNS). Microglia, have pro-inflammatory and subsequently neurotoxic actions as well as anti-inflammatory functions that promote recovery and repair. Very little is known about the transcriptional control of these specific microglial behaviors. We have previously shown that in HIV associated neurocognitive disorders (HAND), the transcription factor p53 accumulates in microglia and that microglial p53 expression is required for the in vitro neurotoxicity of the HIV coat glycoprotein gp120. These findings suggested a novel function for p53 in regulating microglial activation. Here we report that in the absence of p53, microglia demonstrate a blunted response to interferon-γ, failing to increase expression of genes associated with classical macrophage activation or secrete pro-inflammatory cytokines. Microarray analysis of global gene expression profiles revealed increased expression of genes associated with anti-inflammatory functions, phagocytosis and tissue repair in p53 knockout (p53−/−) microglia compared with those cultured from strain matched p53 expressing (p53+/+) mice. We further observed that p53−/− microglia demonstrate increased phagocytic activity in vitro and expression of markers for alternative macrophage activation both in vitro and in vivo. In HAND brain tissue, the alternative activation marker CD163 was expressed in a separate subset of microglia than those demonstrating p53 accumulation. These data suggest that p53 influences microglial behavior, supporting the adoption of a pro-inflammatory phenotype, while p53 deficiency promotes phagocytosis and gene expression associated with alternative activation and anti-inflammatory functions. PMID:21598312

  13. Molecular Basis of Enhanced Activity in Factor VIIa-Trypsin Variants Conveys Insights into Tissue Factor-mediated Allosteric Regulation of Factor VIIa Activity*

    PubMed Central

    Sorensen, Anders B.; Madsen, Jesper J.; Svensson, L. Anders; Pedersen, Anette A.; Østergaard, Henrik; Overgaard, Michael T.; Olsen, Ole H.; Gandhi, Prafull S.

    2016-01-01

    The complex of coagulation factor VIIa (FVIIa), a trypsin-like serine protease, and membrane-bound tissue factor (TF) initiates blood coagulation upon vascular injury. Binding of TF to FVIIa promotes allosteric conformational changes in the FVIIa protease domain and improves its catalytic properties. Extensive studies have revealed two putative pathways for this allosteric communication. Here we provide further details of this allosteric communication by investigating FVIIa loop swap variants containing the 170 loop of trypsin that display TF-independent enhanced activity. Using x-ray crystallography, we show that the introduced 170 loop from trypsin directly interacts with the FVIIa active site, stabilizing segment 215–217 and activation loop 3, leading to enhanced activity. Molecular dynamics simulations and novel fluorescence quenching studies support that segment 215–217 conformation is pivotal to the enhanced activity of the FVIIa variants. We speculate that the allosteric regulation of FVIIa activity by TF binding follows a similar path in conjunction with protease domain N terminus insertion, suggesting a more complete molecular basis of TF-mediated allosteric enhancement of FVIIa activity. PMID:26694616

  14. Influence of abiotic factors on the antimicrobial activity of chitosan.

    PubMed

    Tavaria, Freni K; Costa, Eduardo M; Gens, Eduardo J; Malcata, Francisco Xavier; Pintado, Manuela E

    2013-12-01

    In an effort to bypass the adverse secondary effects attributed to the traditional therapeutic approaches used to treat skin disorders (such as atopic dermatitis), alternative antimicrobials have recently been suggested. One such antimicrobial is chitosan, owing to the already proved biological properties associated with its use. However, the influence of abiotic factors on such activities warrants evaluation. This research effort assessed the antimicrobial activity of chitosan upon skin microorganisms (Staphylococcus aureus, Staphylococcus epidermidis and Escherichia coli) in vitro when subject to a combination of different abiotic factors such as pH, ionic strength, organic acids and free fatty acids. Free fatty acids, ionic strength and pH significantly affected chitosan's capability of reducing the viable numbers of S. aureus. This antimicrobial action was potentiated in the presence of palmitic acid and a lower ionic strength (0.2% NaCl), while a higher ionic strength (0.4% NaCl) favored chitosan's action upon the reduction of viable numbers of S. epidermidis and E. coli. Although further studies are needed, these preliminary results advocate that chitosan can in the future be potentially considered as an antimicrobial of choice when handling symptoms associated with atopic dermatitis.

  15. Loop Dynamics of the Extracellular Domain of Human Tissue Factor and Activation of Factor VIIa

    PubMed Central

    Minazzo, Agnese S.; Darlington, Reuben C.; Ross, J.B. Alexander

    2009-01-01

    Abstract In the crystal structure of the complex between the soluble extracellular domain of tissue factor (sTF) and active-site-inhibited VIIa, residues 91 and 92 in the Pro79-Pro92 loop of sTF interact with the catalytic domain of VIIa. It is not known, however, whether this loop has a role in allosteric activation of VIIa. Time-resolved fluorescence anisotropy measurements of probes covalently bound to sTF mutants E84C and T121C show that binding uninhibited Factor VIIa affects segmental motions in sTF. Glu84 resides in the Pro79-Pro92 loop, and Thr121 resides in the turn between the first and second antiparallel β-strands of the sTF subdomain that interacts with the Gla and EGF1 domains of VIIa; neither Glu84 nor Thr121 makes direct contact with VIIa. Probes bound to T121C report limited segmental flexibility in free sTF, which is lost after VIIa binding. Probes bound to E84C report substantial segmental flexibility in the Pro79-Pro92 loop in free sTF, which is greatly reduced after VIIa binding. Thus, VIIa binding reduces dynamic motions in sTF. In particular, the decrease in the Pro79-Pro92 loop motions indicates that loop entropy has a role in the thermodynamics of the protein-protein interactions involved in allosteric control of VIIa activation. PMID:19167313

  16. Arenavirus Nucleoproteins Prevent Activation of Nuclear Factor Kappa B

    PubMed Central

    Rodrigo, W. W. Shanaka I.; Ortiz-Riaño, Emilio; Pythoud, Christelle; Kunz, Stefan

    2012-01-01

    Arenaviruses include several causative agents of hemorrhagic fever (HF) disease in humans that are associated with high morbidity and significant mortality. Morbidity and lethality associated with HF arenaviruses are believed to involve the dysregulation of the host innate immune and inflammatory responses that leads to impaired development of protective and efficient immunity. The molecular mechanisms underlying this dysregulation are not completely understood, but it is suggested that viral infection leads to disruption of early host defenses and contributes to arenavirus pathogenesis in humans. We demonstrate in the accompanying paper that the prototype member in the family, lymphocytic choriomeningitis virus (LCMV), disables the host innate defense by interfering with type I interferon (IFN-I) production through inhibition of the interferon regulatory factor 3 (IRF3) activation pathway and that the viral nucleoprotein (NP) alone is responsible for this inhibitory effect (C. Pythoud, W. W. Rodrigo, G. Pasqual, S. Rothenberger, L. Martínez-Sobrido, J. C. de la Torre, and S. Kunz, J. Virol. 86:7728–7738, 2012). In this report, we show that LCMV-NP, as well as NPs encoded by representative members of both Old World (OW) and New World (NW) arenaviruses, also inhibits the nuclear translocation and transcriptional activity of the nuclear factor kappa B (NF-κB). Similar to the situation previously reported for IRF3, Tacaribe virus NP (TCRV-NP) does not inhibit NF-κB nuclear translocation and transcriptional activity to levels comparable to those seen with other members in the family. Altogether, our findings demonstrate that arenavirus infection inhibits NF-κB-dependent innate immune and inflammatory responses, possibly playing a key role in the pathogenesis and virulence of arenavirus. PMID:22623788

  17. Arenavirus nucleoproteins prevent activation of nuclear factor kappa B.

    PubMed

    Rodrigo, W W Shanaka I; Ortiz-Riaño, Emilio; Pythoud, Christelle; Kunz, Stefan; de la Torre, Juan C; Martínez-Sobrido, Luis

    2012-08-01

    Arenaviruses include several causative agents of hemorrhagic fever (HF) disease in humans that are associated with high morbidity and significant mortality. Morbidity and lethality associated with HF arenaviruses are believed to involve the dysregulation of the host innate immune and inflammatory responses that leads to impaired development of protective and efficient immunity. The molecular mechanisms underlying this dysregulation are not completely understood, but it is suggested that viral infection leads to disruption of early host defenses and contributes to arenavirus pathogenesis in humans. We demonstrate in the accompanying paper that the prototype member in the family, lymphocytic choriomeningitis virus (LCMV), disables the host innate defense by interfering with type I interferon (IFN-I) production through inhibition of the interferon regulatory factor 3 (IRF3) activation pathway and that the viral nucleoprotein (NP) alone is responsible for this inhibitory effect (C. Pythoud, W. W. Rodrigo, G. Pasqual, S. Rothenberger, L. Martínez-Sobrido, J. C. de la Torre, and S. Kunz, J. Virol. 86:7728-7738, 2012). In this report, we show that LCMV-NP, as well as NPs encoded by representative members of both Old World (OW) and New World (NW) arenaviruses, also inhibits the nuclear translocation and transcriptional activity of the nuclear factor kappa B (NF-κB). Similar to the situation previously reported for IRF3, Tacaribe virus NP (TCRV-NP) does not inhibit NF-κB nuclear translocation and transcriptional activity to levels comparable to those seen with other members in the family. Altogether, our findings demonstrate that arenavirus infection inhibits NF-κB-dependent innate immune and inflammatory responses, possibly playing a key role in the pathogenesis and virulence of arenavirus.

  18. Virulence factor activity relationships (VFARs): a bioinformatics perspective.

    PubMed

    Waseem, Hassan; Williams, Maggie R; Stedtfeld, Tiffany; Chai, Benli; Stedtfeld, Robert D; Cole, James R; Tiedje, James M; Hashsham, Syed A

    2017-03-06

    Virulence factor activity relationships (VFARs) - a concept loosely based on quantitative structure-activity relationships (QSARs) for chemicals was proposed as a predictive tool for ranking risks due to microorganisms relevant to water safety. A rapid increase in sequencing capabilities and bioinformatics tools has significantly increased the potential for VFAR-based analyses. This review summarizes more than 20 bioinformatics databases and tools, developed over the last decade, along with their virulence and antimicrobial resistance prediction capabilities. With the number of bacterial whole genome sequences exceeding 241 000 and metagenomic analysis projects exceeding 13 000 and the ability to add additional genome sequences for few hundred dollars, it is evident that further development of VFARs is not limited by the availability of information at least at the genomic level. However, additional information related to co-occurrence, treatment response, modulation of virulence due to environmental and other factors, and economic impact must be gathered and incorporated in a manner that also addresses the associated uncertainties. Of the bioinformatics tools, a majority are either designed exclusively for virulence/resistance determination or equipped with a dedicated module. The remaining have the potential to be employed for evaluating virulence. This review focusing broadly on omics technologies and tools supports the notion that these tools are now sufficiently developed to allow the application of VFAR approaches combined with additional engineering and economic analyses to rank and prioritize organisms important to a given niche. Knowledge gaps do exist but can be filled with focused experimental and theoretical analyses that were unimaginable a decade ago. Further developments should consider the integration of the measurement of activity, risk, and uncertainty to improve the current capabilities.

  19. Coagulation factor V mediates inhibition of tissue factor signaling by activated protein C in mice

    PubMed Central

    Liang, Hai Po H.; Kerschen, Edward J.; Basu, Sreemanti; Hernandez, Irene; Zogg, Mark; Jia, Shuang; Hessner, Martin J.; Toso, Raffaella; Rezaie, Alireza R.; Fernández, José A.; Camire, Rodney M.; Ruf, Wolfram; Griffin, John H.

    2015-01-01

    The key effector molecule of the natural protein C pathway, activated protein C (aPC), exerts pleiotropic effects on coagulation, fibrinolysis, and inflammation. Coagulation-independent cell signaling by aPC appears to be the predominant mechanism underlying its highly reproducible therapeutic efficacy in most animal models of injury and infection. In this study, using a mouse model of Staphylococcus aureus sepsis, we demonstrate marked disease stage–specific effects of the anticoagulant and cell signaling functions of aPC. aPC resistance of factor (f)V due to the R506Q Leiden mutation protected against detrimental anticoagulant effects of aPC therapy but also abrogated the anti-inflammatory and mortality-reducing effects of the signaling-selective 5A-aPC variant that has minimal anticoagulant function. We found that procofactor V (cleaved by aPC at R506) and protein S were necessary cofactors for the aPC-mediated inhibition of inflammatory tissue-factor signaling. The anti-inflammatory cofactor function of fV involved the same structural features that govern its cofactor function for the anticoagulant effects of aPC, yet its anti-inflammatory activities did not involve proteolysis of activated coagulation factors Va and VIIIa. These findings reveal a novel biological function and mechanism of the protein C pathway in which protein S and the aPC-cleaved form of fV are cofactors for anti-inflammatory cell signaling by aPC in the context of endotoxemia and infection. PMID:26341257

  20. Crystal Structure of Human Plasma Platelet-Activating Factor Acetylhydrolase

    SciTech Connect

    Samanta, U.; Bahnson, B

    2008-01-01

    Human plasma platelet-activating factor (PAF) acetylhydrolase functions by reducing PAF levels as a general anti-inflammatory scavenger and is linked to anaphylactic shock, asthma, and allergic reactions. The enzyme has also been implicated in hydrolytic activities of other pro-inflammatory agents, such as sn-2 oxidatively fragmented phospholipids. This plasma enzyme is tightly bound to low and high density lipoprotein particles and is also referred to as lipoprotein-associated phospholipase A{sub 2}. The crystal structure of this enzyme has been solved from x-ray diffraction data collected to a resolution of 1.5{angstrom}. It has a classic lipase {alpha}/{beta}-hydrolase fold, and it contains a catalytic triad of Ser{sup 273}, His{sup 351}, and Asp{sup 296}. Two clusters of hydrophobic residues define the probable interface-binding region, and a prediction is given of how the enzyme is bound to lipoproteins. Additionally, an acidic patch of 10 carboxylate residues and a neighboring basic patch of three residues are suggested to play a role in high density lipoprotein/low density lipoprotein partitioning. A crystal structure is also presented of PAF acetylhydrolase reacted with the organophosphate compound paraoxon via its active site Ser{sup 273}. The resulting diethyl phosphoryl complex was used to model the tetrahedral intermediate of the substrate PAF to the active site. The model of interface binding begins to explain the known specificity of lipoprotein-bound substrates and how the active site can be both close to the hydrophobic-hydrophilic interface and at the same time be accessible to the aqueous phase.

  1. Associations between Socio-Motivational Factors, Physical Education Activity Levels and Physical Activity Behavior among Youth

    ERIC Educational Resources Information Center

    Ning, Weihong; Gao, Zan; Lodewyk, Ken

    2012-01-01

    This study examined the relationships between established socio-motivational factors and children's physical activity levels daily and during physical education classes. A total of 307 middle school students (149 boys, 158 girls) from a suburban public school in the Southern United States participated in this study. Participants completed…

  2. Blood B Lymphocyte Stimulator (BLyS)/BAFF levels may reflect natural immunity to HIV in highly exposed uninfected Beninese Commercial Sex Workers

    PubMed Central

    Sabourin-Poirier, Catherine; Fourcade, Lyvia; Chagnon-Choquet, Josiane; Labbé, Annie-Claude; Alary, Michel; Guédou, Fernand; Poudrier, Johanne; Roger, Michel

    2016-01-01

    We have previously shown that excess B lymphocyte Stimulator (BLyS)/BAFF in plasma and on surface of blood dendritic cells (DC) of HIV-infected progressors coincides with B-cell dysregulations and increased frequencies of “precursor” innate marginal zone (MZ)-like B-cells. In contrast, both blood BLyS levels and frequencies of this population remained unaltered in HIV elite-controllers. Based on these observations, we hypothesized that control of BLyS and innate B-cell status could be associated with natural immunity against HIV infection. Therefore, we assessed blood BLyS levels and B-cell status in HIV highly-exposed commercial sex workers (CSWs) from Benin. We found blood BLyS levels of HIV-uninfected CSWs were lower than those observed in both HIV-infected CSW and HIV-uninfected non-CSW groups. Furthermore, levels of BLyS expression on blood T-cells and monocytes were lower in HIV-uninfected CSWs when compared to HIV-infected CSWs, but higher than those observed for HIV-uninfected non-CSWs. Concomitantly, HIV-infected CSWs presented a dysregulated blood B-cell compartment, characterized by increased total IgG1, increased frequencies of populations presenting immature and/or innate profiles and a higher ratio of IgG+/IgA+ plasmablasts. In contrast, relatively low levels of BLyS in the blood of HIV-uninfected CSWs coincided with a rather preserved B-cell compartment. PMID:27561453

  3. Atrial natriuretic factor-like activity in rat posterior pituitary

    SciTech Connect

    Gutkowska, J.; Debinski, W.; Racz, K.; Thibault, G.; Garcia, R.; Kuchel, O.; Genest, J.; Cantin, M.

    1986-03-05

    The presence of a biologically active peptide: Atrial Natriuretic Factor (ANF) has been demonstrated in rat and human circulation and ANF is considered now as a new hormone. ANF may be involved in body fluid regulation. A very sensitive radioimmunoassay for rat ANF allowed the authors to search for immunoreactive ANF (IR-ANF) in rat posterior pituitary. Serial dilutions of homogenates of rat posterior pituitary showed a good parallelism with a reference curve in a radioimmunoassay system. The IR-ANF was extracted from rat posterior pituitary homogenates by activated Vycor glass beads. The lyophilized extract was purified by HPLC on C/sub 18/ ..mu.. Bondapak column. The HPLC yielded two IR-ANF peaks. Both isolated ANF-like material showed biological activity. The IR-ANF eluted with 33% acetonitrile, inhibited ACTH-stimulated aldosterone secretion with a similar potency as synthetic (Arg 101 - Tyr 126) ANF (0.7 x 10/sup -10/M). A much less potent ANF-like material was found in the second peak eluted with 36% acetonitrile. They conclude that ANF-like material is present in rat posterior pituitary and this suggest a possible role in ANF on AVP secretion directly in situ.

  4. Deficiency of platelet-activating factor acetylhydrolase is a severity factor for asthma

    PubMed Central

    Stafforini, Diana M.; Numao, Toshio; Tsodikov, Alexander; Vaitkus, Darius; Fukuda, Takeshi; Watanabe, Naoto; Fueki, Naoto; McIntyre, Thomas M.; Zimmerman, Guy A.; Makino, Sohei; Prescott, Stephen M.

    1999-01-01

    Asthma, a family of airway disorders characterized by airway inflammation, has an increasing incidence worldwide. Platelet-activating factor (PAF) may play a role in the pathophysiology of asthma. Its proinflammatory actions are antagonized by PAF acetylhydrolase. A missense mutation (V279F) in the PAF acetylhydrolase gene results in the complete loss of activity, which occurs in 4% of the Japanese population. We asked if PAF acetylhydrolase deficiency correlates with the incidence and severity of asthma in Japan. We found that the prevalence of PAF acetylhydrolase deficiency is higher in Japanese asthmatics than healthy subjects and that the severity of this syndrome is highest in homozygous-deficient subjects. We conclude that the PAF acetylhydrolase gene is a modulating locus for the severity of asthma. PMID:10194471

  5. Modeling of human factor Va inactivation by activated protein C

    PubMed Central

    2012-01-01

    Background Because understanding of the inventory, connectivity and dynamics of the components characterizing the process of coagulation is relatively mature, it has become an attractive target for physiochemical modeling. Such models can potentially improve the design of therapeutics. The prothrombinase complex (composed of the protease factor (F)Xa and its cofactor FVa) plays a central role in this network as the main producer of thrombin, which catalyses both the activation of platelets and the conversion of fibrinogen to fibrin, the main substances of a clot. A key negative feedback loop that prevents clot propagation beyond the site of injury is the thrombin-dependent generation of activated protein C (APC), an enzyme that inactivates FVa, thus neutralizing the prothrombinase complex. APC inactivation of FVa is complex, involving the production of partially active intermediates and “protection” of FVa from APC by both FXa and prothrombin. An empirically validated mathematical model of this process would be useful in advancing the predictive capacity of comprehensive models of coagulation. Results A model of human APC inactivation of prothrombinase was constructed in a stepwise fashion by analyzing time courses of FVa inactivation in empirical reaction systems with increasing number of interacting components and generating corresponding model constructs of each reaction system. Reaction mechanisms, rate constants and equilibrium constants informing these model constructs were initially derived from various research groups reporting on APC inactivation of FVa in isolation, or in the presence of FXa or prothrombin. Model predictions were assessed against empirical data measuring the appearance and disappearance of multiple FVa degradation intermediates as well as prothrombinase activity changes, with plasma proteins derived from multiple preparations. Our work integrates previously published findings and through the cooperative analysis of in vitro

  6. Phylogenomics of caspase-activated DNA fragmentation factor

    SciTech Connect

    Eckhart, Leopold . E-mail: leopold.eckhart@meduniwien.ac.at; Fischer, Heinz; Tschachler, Erwin

    2007-04-27

    The degradation of nuclear DNA by DNA fragmentation factor (DFF) is a key step in apoptosis of mammalian cells. Using comparative genomics, we have here determined the evolutionary history of the genes encoding the two DFF subunits, DFFA (also known as ICAD) and DFFB (CAD). Orthologs of DFFA and DFFB were identified in Nematostella vectensis, a representative of the primitive metazoan clade cnidarians, and in various vertebrates and insects, but not in representatives of urochordates, echinoderms, and nematodes. The domains mediating the interaction of DFFA and DFFB, a caspase cleavage site in DFFA, and the amino acid residues critical for endonuclease activity of DFFB were conserved in Nematostella. These findings suggest that DFF has been a part of the primordial apoptosis system of the eumetazoan common ancestor and that the ancient cell death machinery has degenerated in several evolutionary lineages, including the one leading to the prototypical apoptosis model, Caenorhabditis elegans.

  7. Human factors in remote control engineering development activities

    SciTech Connect

    Clarke, M.M.; Hamel, W.R.; Draper, J.V.

    1983-01-01

    Human factors engineering, which is an integral part of the advanced remote control development activities at the Oak Ridge National Laboratory, is described. First, work at the Remote Systems Development Facility (RSDF) has shown that operators can perform a wide variety of tasks, some of which were not specifically designed for remote systems, with a dextrous electronic force-reflecting servomanipulator and good television remote viewing capabilities. Second, the data collected during mock-up remote maintenance experiments at the RSDF have been analyzed to provide guidelines for the design of human interfaces with an integrated advanced remote maintenance system currently under development. Guidelines have been provided for task allocation between operators, remote viewing systems, and operator controls. 6 references, 5 figures, 2 tables.

  8. Activating transcription factor 3 regulates immune and metabolic homeostasis.

    PubMed

    Rynes, Jan; Donohoe, Colin D; Frommolt, Peter; Brodesser, Susanne; Jindra, Marek; Uhlirova, Mirka

    2012-10-01

    Integration of metabolic and immune responses during animal development ensures energy balance, permitting both growth and defense. Disturbed homeostasis causes organ failure, growth retardation, and metabolic disorders. Here, we show that the Drosophila melanogaster activating transcription factor 3 (Atf3) safeguards metabolic and immune system homeostasis. Loss of Atf3 results in chronic inflammation and starvation responses mounted primarily by the larval gut epithelium, while the fat body suffers lipid overload, causing energy imbalance and death. Hyperactive proinflammatory and stress signaling through NF-κB/Relish, Jun N-terminal kinase, and FOXO in atf3 mutants deregulates genes important for immune defense, digestion, and lipid metabolism. Reducing the dose of either FOXO or Relish normalizes both lipid metabolism and gene expression in atf3 mutants. The function of Atf3 is conserved, as human ATF3 averts some of the Drosophila mutant phenotypes, improving their survival. The single Drosophila Atf3 may incorporate the diversified roles of two related mammalian proteins.

  9. Control of mechanically activated polymersome fusion: Factors affecting fusion

    DOE PAGES

    Henderson, Ian M.; Paxton, Walter F.

    2014-12-15

    Previously we have studied the mechanically-activated fusion of extruded (200 nm) polymer vesicles into giant polymersomes using agitation in the presence of salt. In this study we have investigated several factors contributing to this phenomenon, including the effects of (i) polymer vesicle concentration, (ii) agitation speed and duration, and iii) variation of the salt and its concentration. It was found that increasing the concentration of the polymer dramatically increases the production of giant vesicles through the increased collisions of polymersomes. Our investigations also found that increasing the frequency of agitation increased the efficiency of fusion, though ultimately limited the sizemore » of vesicle which could be produced due to the high shear involved. Finally it was determined that salt-mediation of the fusion process was not limited to NaCl, but is instead a general effect facilitated by the presence of solvated ionic compounds, albeit with different salts initiating fusion at different concentration.« less

  10. Control of mechanically activated polymersome fusion: Factors affecting fusion

    SciTech Connect

    Henderson, Ian M.; Paxton, Walter F.

    2014-12-15

    Previously we have studied the mechanically-activated fusion of extruded (200 nm) polymer vesicles into giant polymersomes using agitation in the presence of salt. In this study we have investigated several factors contributing to this phenomenon, including the effects of (i) polymer vesicle concentration, (ii) agitation speed and duration, and iii) variation of the salt and its concentration. It was found that increasing the concentration of the polymer dramatically increases the production of giant vesicles through the increased collisions of polymersomes. Our investigations also found that increasing the frequency of agitation increased the efficiency of fusion, though ultimately limited the size of vesicle which could be produced due to the high shear involved. Finally it was determined that salt-mediation of the fusion process was not limited to NaCl, but is instead a general effect facilitated by the presence of solvated ionic compounds, albeit with different salts initiating fusion at different concentration.

  11. Arenavirus nucleoprotein targets interferon regulatory factor-activating kinase IKKε.

    PubMed

    Pythoud, Christelle; Rodrigo, W W Shanaka I; Pasqual, Giulia; Rothenberger, Sylvia; Martínez-Sobrido, Luis; de la Torre, Juan Carlos; Kunz, Stefan

    2012-08-01

    Arenaviruses perturb innate antiviral defense by blocking induction of type I interferon (IFN) production. Accordingly, the arenavirus nucleoprotein (NP) was shown to block activation and nuclear translocation of interferon regulatory factor 3 (IRF3) in response to virus infection. Here, we sought to identify cellular factors involved in innate antiviral signaling targeted by arenavirus NP. Consistent with previous studies, infection with the prototypic arenavirus lymphocytic choriomeningitis virus (LCMV) prevented phosphorylation of IRF3 in response to infection with Sendai virus, a strong inducer of the retinoic acid-inducible gene I (RIG-I)/mitochondrial antiviral signaling (MAVS) pathway of innate antiviral signaling. Using a combination of coimmunoprecipitation and confocal microscopy, we found that LCMV NP associates with the IκB kinase (IKK)-related kinase IKKε but that, rather unexpectedly, LCMV NP did not bind to the closely related TANK-binding kinase 1 (TBK-1). The NP-IKKε interaction was highly conserved among arenaviruses from different clades. In LCMV-infected cells, IKKε colocalized with NP but not with MAVS located on the outer membrane of mitochondria. LCMV NP bound the kinase domain (KD) of IKKε (IKBKE) and blocked its autocatalytic activity and its ability to phosphorylate IRF3, without undergoing phosphorylation. Together, our data identify IKKε as a novel target of arenavirus NP. Engagement of NP seems to sequester IKKε in an inactive complex. Considering the important functions of IKKε in innate antiviral immunity and other cellular processes, the NP-IKKε interaction likely plays a crucial role in arenavirus-host interaction.

  12. Allosteric activation of ADAMTS13 by von Willebrand factor.

    PubMed

    Muia, Joshua; Zhu, Jian; Gupta, Garima; Haberichter, Sandra L; Friedman, Kenneth D; Feys, Hendrik B; Deforche, Louis; Vanhoorelbeke, Karen; Westfield, Lisa A; Roth, Robyn; Tolia, Niraj Harish; Heuser, John E; Sadler, J Evan

    2014-12-30

    The metalloprotease ADAMTS13 cleaves von Willebrand factor (VWF) within endovascular platelet aggregates, and ADAMTS13 deficiency causes fatal microvascular thrombosis. The proximal metalloprotease (M), disintegrin-like (D), thrombospondin-1 (T), Cys-rich (C), and spacer (S) domains of ADAMTS13 recognize a cryptic site in VWF that is exposed by tensile force. Another seven T and two complement C1r/C1s, sea urchin epidermal growth factor, and bone morphogenetic protein (CUB) domains of uncertain function are C-terminal to the MDTCS domains. We find that the distal T8-CUB2 domains markedly inhibit substrate cleavage, and binding of VWF or monoclonal antibodies to distal ADAMTS13 domains relieves this autoinhibition. Small angle X-ray scattering data indicate that distal T-CUB domains interact with proximal MDTCS domains. Thus, ADAMTS13 is regulated by substrate-induced allosteric activation, which may optimize VWF cleavage under fluid shear stress in vivo. Distal domains of other ADAMTS proteases may have similar allosteric properties.

  13. Essential role of platelet activation via protease activated receptor 4 in tissue factor-initiated inflammation

    PubMed Central

    Busso, Nathalie; Chobaz-Péclat, Veronique; Hamilton, Justin; Spee, Pieter; Wagtmann, Nicolai; So, Alexander

    2008-01-01

    Introduction Tissue factor (TF) activation of the coagulation proteases enhances inflammation in animal models of arthritis and endotoxemia, but the mechanism of this effect is not yet fully understood – in particular, whether this is primarily due to fibrin formation or through activation of protease activated receptors (PARs). Methods We induced extravascular inflammation by injection of recombinant soluble murine TF (sTF1–219) in the hind paw. The effects of thrombin inhibition, fibrinogen and platelet depletion were evaluated, as well as the effects of PAR deficiency using knockout mice deficient for each of the PARs. Results Injection of soluble TF provoked a rapid onset of paw swelling. Inflammation was confirmed histologically and by increased serum IL-6 levels. Inflammation was significantly reduced by depletion of fibrinogen (P < 0.05) or platelets (P = 0.015), and by treatment with hirudin (P = 0.04) or an inhibitor of activated factor VII (P < 0.001) compared with controls. PAR-4-deficient mice exhibited significantly reduced paw swelling (P = 0.003). In contrast, a deficiency in either PAR-1, PAR-2 or PAR-3 did not affect the inflammatory response to soluble TF injection. Conclusion Our results show that soluble TF induces acute inflammation through a thrombin-dependent pathway and both fibrin deposition and platelet activation are essential steps in this process. The activation of PAR-4 on platelets is crucial and the other PARs do not play a major role in soluble TF-induced inflammation. PMID:18412955

  14. Immunoglobulin D enhances immune surveillance by activating antimicrobial, proinflammatory and B cell-stimulating programs in basophils.

    PubMed

    Chen, Kang; Xu, Weifeng; Wilson, Melanie; He, Bing; Miller, Norman W; Bengtén, Eva; Edholm, Eva-Stina; Santini, Paul A; Rath, Poonam; Chiu, April; Cattalini, Marco; Litzman, Jiri; B Bussel, James; Huang, Bihui; Meini, Antonella; Riesbeck, Kristian; Cunningham-Rundles, Charlotte; Plebani, Alessandro; Cerutti, Andrea

    2009-08-01

    Immunoglobulin D (IgD) is an enigmatic antibody isotype that mature B cells express together with IgM through alternative RNA splicing. Here we report active T cell-dependent and T cell-independent IgM-to-IgD class switching in B cells of the human upper respiratory mucosa. This process required activation-induced cytidine deaminase (AID) and generated local and circulating IgD-producing plasmablasts reactive to respiratory bacteria. Circulating IgD bound to basophils through a calcium-mobilizing receptor that induced antimicrobial, opsonizing, inflammatory and B cell-stimulating factors, including cathelicidin, interleukin 1 (IL-1), IL-4 and B cell-activating factor (BAFF), after IgD crosslinking. By showing dysregulation of IgD class-switched B cells and 'IgD-armed' basophils in autoinflammatory syndromes with periodic fever, our data indicate that IgD orchestrates an ancestral surveillance system at the interface between immunity and inflammation.

  15. Hemophilia as a defect of the tissue factor pathway of blood coagulation: Effect of factors VIII and IX on factor X activation in a continuous-flow reactor

    SciTech Connect

    Repke, D.; Gemmell, C.H.; Guha, A.; Turitto, V.T.; Nemerson, Y. ); Broze, G.J. Jr. )

    1990-10-01

    The effect of factors VIII and IX on the ability of the tissue factor-factor VIIa complex to activate factor X was studied in a continuous-flow tubular enzyme reactor. Tissue factor immobilized in a phospholipid bilayer on the inner surface of the tube was exposed to a perfusate containing factors VIIa, VIII, IX, and X flowing at a wall shear rate of 57, 300, or 1130 sec{sup {minus}1}. The addition of factors VIII and IX at their respective plasma concentrations resulted in a further 2{endash}-to 3{endash}fold increase. The direct activation of factor X by tissue factor-factor VIIa could be virtually eliminated by the lipoprotein-associated coagulation inhibitor. These results suggest that the tissue factor pathway, mediated through factors VIII and IX, produces significant levels of factor Xa even in the presence of an inhibitor of the tissue factor-factor VIIa complex; moreover, the activation is dependent on local shear conditions. These findings are consistent both with a model of blood coagulation in which initiation of the system results from tissue factor and with the bleeding observed in hemophilia.

  16. Platelet-activating factor: receptors and signal transduction.

    PubMed

    Chao, W; Olson, M S

    1993-06-15

    During the past two decades, studies describing the chemistry and biology of PAF have been extensive. This potent phosphoacylglycerol exhibits a wide variety of physiological and pathophysiological effects in various cells and tissues. PAF acts, through specific receptors and a variety of signal transduction systems, to elicit diverse biochemical responses. Several important future directions can be enumerated for the characterization of PAF receptors and their attendant signalling mechanisms. The recent cloning and sequence analysis of the gene for the PAF receptor will allow a number of important experimental approaches for characterizing the structure and analysing the function of the various domains of the receptor. Using molecular genetic and immunological technologies, questions relating to whether there is receptor heterogeneity, the precise mechanism(s) for the regulation of the PAF receptor, and the molecular details of the signalling mechanisms in which the PAF receptor is involved can be explored. Another area of major significance is the examination of the relationship between the signalling response(s) evoked by PAF binding to its receptor and signalling mechanisms activated by a myriad of other mediators, cytokines and growth factors. A very exciting recent development in which PAF receptors undoubtedly play a role is in the regulation of the function of various cellular adhesion molecules. Finally, there remain many incompletely characterized physiological and pathophysiological situations in which PAF and its receptor play a crucial signalling role. Our laboratory has been active in the elucidation of several tissue responses in which PAF exhibits major autocoid signalling responses, e.g. hepatic injury and inflammation, acute and chronic pancreatitis, and cerebral stimulation and/or trauma. As new experimental strategies are developed for characterizing the fine structure of the molecular mechanisms involved in tissue injury and inflammation, the

  17. Complement factor B activation in patients with preeclampsia.

    PubMed

    Velickovic, Ivan; Dalloul, Mudar; Wong, Karen A; Bakare, Olufunke; Schweis, Franz; Garala, Maya; Alam, Amit; Medranda, Giorgio; Lekovic, Jovana; Shuaib, Waqas; Tedjasukmana, Andreas; Little, Perry; Hanono, Daniel; Wijetilaka, Ruvini; Weedon, Jeremy; Lin, Jun; Toledano, Roulhac d'Arby; Zhang, Ming

    2015-06-01

    Preeclampsia is a leading cause of maternal and fetal morbidity and mortality. Bb, the active fragment of complement factor B (fB), has been reported to be a predictor of preeclampsia. However, conflicting results have been found by some investigators. We hypothesized that the disagreement in findings may be due to the racial/ethnic differences among various study groups, and that fB activation is significant in women of an ethnic minority with preeclampsia. We investigated the maternal and fetal levels of Bb (the activated fB fragment) in pregnant women of an ethnic minority with or without preeclampsia. We enrolled 291 pregnant women (96% of an ethnic minority, including 78% African-American). Thirteen percent of these were diagnosed with preeclampsia. Maternal venous blood was collected from all participants together with fetal umbilical cord blood samples from 154 deliveries in the 291 women. The results were analyzed using the Mann-Whitney U test and multivariate analyses. Maternal Bb levels were significantly higher in the preeclamptic group than in the nonpreeclamptic group. Levels of Bb in fetal cord blood were similar in both groups. Subgroup analyses of African-American patients' results confirmed the study hypothesis that there would be a significant increase in Bb in the maternal blood of the preeclamptic group and no increase in Bb in the fetal cord blood of this group. These results suggest that a maternal immune response through complement fB might play a role in the development of preeclampsia, particularly in African-American patients.

  18. Prediction of Pathway Activation by Xenobiotic-Responsive Transcription Factors in the Mouse Liver

    EPA Science Inventory

    Many drugs and environmentally-relevant chemicals activate xenobioticresponsive transcription factors (TF). Identification of target genes of these factors would be useful in predicting pathway activation in in vitro chemical screening. Starting with a large compendium of Affymet...

  19. Activation and function of human Hageman factor. The role of high molecular weight kininogen and prekallikrein.

    PubMed Central

    Meier, H L; Pierce, J V; Colman, R W; Kaplan, A P

    1977-01-01

    The activation and function of surface-bound Hageman factor in human plasma are dependent upon both high molecular weight (HMW) kininogen and prekallikrein. HMW kininogen does not affect the binding of Hageman factor to surfaces, but it enhances the function of surface-bound Hageman factor as assessed by its ability to activate prekallikrein and Factor XI. The initial conversion of prekallikrein to kallikrein by the surface-bound Hageman factor in the presence of HMW kininogen is followed by a rapid enzymatic activation of Hageman factor by kallikrein. The latter interaction is also facilitated by HMW kininogen. Kallikrein therefore functions as an activator of Hageman factor by a positive feedback mechanism and generates most of the activated Hageman factor during brief exposure of plasma to activating surfaces. HMW kininogen is a cofactor in the enzymatic activation of Hageman factor by kallikrein and it also augments the function of the activated Hageman factor generated. The stoichiometry of the Hagman factor interaction with HMW kininogen suggests that it enhances the activity of the active site of Hageman factor. Since HMW kininogen and prekallikrein circulate as a complex, HMW kininogen may also place the prekallikrein in an optimal position for its reciprocal interaction with Hageman factor to proceed. The surface appears to play a passive role upon which bound Hageman factor and the prekallikrein-HMW kininogen complex can interact. PMID:874082

  20. Water Activity Limits the Hygroscopic Growth Factor of Organic Aerosols

    NASA Astrophysics Data System (ADS)

    Rodriguez, L. I.; Cabrera, J. A.; Golden, D.; Tabazadeh, A.

    2007-12-01

    In this work we study the hygroscopic behavior of organic aerosols, which has important implications for Earth's climate. The hygroscopic growth factor (HGF) is defined as the ratio of the diameter of a spherical particle when it is exposed to dry conditions to that at humid conditions. We present a new formulation to express the HGF of an aerosol particle as a function of water activity (aw) in the aqueous phase. This new formulation matches reported HGFs for common inorganic salts and water-miscible organic particles that are known to deliquesce into aqueous drops at high relative humidities (RH). Many studies use tandem differential mobility analyzers (TDMA) to determine the HGF of organic aerosols. For example, Brooks et al. used a TDMA to measure a HGF of 1.2 for 2 μm phthalic acid (PA) particles at 90% RH (aw= 0.9). However, water activity limits the growth of a particle that can be attributed to water uptake. We have assembled a vapor pressure apparatus to measure aw of aqueous solutions at room temperature. Measured water activities for PA, used in our growth formulation, yield a HGF of ~ 1.0005 for 2 μm PA particles at 90% RH. Comparing our results against Brooks et al. suggests that TDMA experiments may grossly overestimate the HGF of PA particles since water activity limits this growth to below 1.0005. Alternatively, we suggest that the adsorption of a negligible mass of water by a highly porous PA particle can lead to an apparent growth in particle size by changing its morphology. Other studies also use TDMAs to measure HGFs of secondary organic aerosols (SOAs). HGFs reported for SOAs are very similar to PA, suggesting that the observed growth may be due to morphological changes in particle size rather than water uptake as commonly assumed. We built a smog chamber where an organic precursor, such as d-limonene, reacts with nitrogen oxides under UV radiation to produce SOAs. We compare the HGFs for SOAs obtained with our method to those obtained with

  1. Rifampicin Attenuated Global Cerebral Ischemia Injury via Activating the Nuclear Factor Erythroid 2-Related Factor Pathway

    PubMed Central

    Chen, Beibei; Cao, Huimin; Chen, Lili; Yang, Xuemei; Tian, Xiaoyan; Li, Rong; Cheng, Oumei

    2016-01-01

    Background: Recent studies have found that rifampicin has neuroprotective properties in neurodegenerative diseases. However, the exact mechanisms of action remain unclear. The nuclear factor erythroid 2-related factor 2 (Nrf2) has been considered a potential target for neuroprotection. In this study, we examined whether rifampicin exhibits beneficial effects mediated by the Nrf2 pathway after global cerebral ischemia (GCI). Methods: Rats were randomly assigned to four groups that included a sham group and three treatment groups with global ischemia-reperfusion [control, rifampicin, and rifampicin plus brusatol (an inhibitor of Nrf2)]. Rats were subjected to transient GCI induced by bilateral common carotid artery occlusion for 20 min with systemic hypotension by blood withdrawal. The Morris water maze test was performed for neurobehavioral testing, whereas the pathological changes were investigated using HE and TUNEL staining. The protein expression of Nrf2, hemeoxygenase-1 (HO-1) and cyclooxygenase-2 (COX-2) in the hippocampus were analyzed by Western blotting. The immunofluorescence staining was used to determine the distribution of Nrf2. Results: Rifampicin treatment significantly improved spatial learning ability compared with the control group, which was consistent with the pathological changes. In addition, rifampicin significantly elevated the nuclear expression of Nrf2, Nrf2 downstream anti-oxidant protein, HO-1 compared with the control group, and it simultaneously downregulated the expression of COX-2 in the hippocampus on day 3 after ischemia-reperfusion. Interestingly, the forenamed effects of rifampicin were abolished by pretreatment with brusatol, a specific inhibitor of Nrf2 activation. Conclusions: Rifampicin exerts neuroprotective effects against global cerebral ischemia, which may be attributed to activation of the Nrf2 pathway. PMID:27965540

  2. Tumor necrosis factor alpha-induced angiogenesis depends on in situ platelet-activating factor biosynthesis

    PubMed Central

    1994-01-01

    Tumor necrosis factor (TNF) alpha, a potent inhibitor of endothelial cell growth in vitro, is angiogenic in vivo. Therefore, it was suggested that the angiogenic properties of this agent might be consequent to the production of secondary mediators. Since TNF-alpha stimulates the synthesis of platelet-activating factor (PAF) by monocytes and endothelial cells, we investigated the possible involvement of PAF in the angiogenic effect of TNF-alpha. Angiogenesis was studied in a murine model in which Matrigel was used as a vehicle for the delivery of mediators. In this model the angiogenesis induced by TNF-alpha was shown to be inhibited by WEB 2170, a specific PAF receptor antagonist. Moreover, in mice injected with TNF-alpha, PAF was detected within the Matrigel, 6 and 24 h after TNF-alpha injection. The synthesis of PAF within the Matrigel was concomitant with the early migration of endothelial cells and infiltration of monocytes. No infiltration of lymphocytes or polymorphonuclear leukocytes was observed. Synthetic PAF as well as PAF extracted and purified from mice challenged with TNF-alpha induced a rapid angiogenic response, inhibited by WEB 2170. These results suggest that the angiogenic effect of TNF-alpha is, at least in part, mediated by PAF synthesized from monocytes and/or endothelial cells infiltrating the Matrigel plug. PMID:7516414

  3. Selective Activation of Human Dendritic Cells by OM-85 through a NF-kB and MAPK Dependent Pathway

    PubMed Central

    Scutera, Sara; Somma, Paolo; Salvi, Valentina; Musso, Tiziana; Tabbia, Giuseppe; Bardessono, Marco; Pasquali, Christian; Mantovani, Alberto; Sozzani, Silvano; Bosisio, Daniela

    2013-01-01

    OM-85 (Broncho-Vaxom®, Broncho-Munal®, Ommunal®, Paxoral®, Vaxoral®), a product made of the water soluble fractions of 21 inactivated bacterial strain patterns responsible for respiratory tract infections, is used for the prevention of recurrent upper respiratory tract infections and acute exacerbations in chronic obstructive pulmonary disease patients. OM-85 is able to potentiate both innate and adaptive immune responses. However, the molecular mechanisms responsible for OM-85 activation are still largely unknown. Purpose of this study was to investigate the impact of OM-85 stimulation on human dendritic cell functions. We show that OM-85 selectively induced NF-kB and MAPK activation in human DC with no detectable action on the interferon regulatory factor (IRF) pathway. As a consequence, chemokines (i.e. CXCL8, CXCL6, CCL3, CCL20, CCL22) and B-cell activating cytokines (i.e. IL-6, BAFF and IL-10) were strongly upregulated. OM-85 also synergized with the action of classical pro-inflammatory stimuli used at suboptimal concentrations. Peripheral blood mononuclear cells from patients with COPD, a pathological condition often associated with altered PRR expression pattern, fully retained the capability to respond to OM-85. These results provide new insights on the molecular mechanisms of OM-85 activation of the immune response and strengthen the rational for its use in clinical settings. PMID:24386121

  4. Activating Transcription Factor 3 Regulates Immune and Metabolic Homeostasis

    PubMed Central

    Rynes, Jan; Donohoe, Colin D.; Frommolt, Peter; Brodesser, Susanne; Jindra, Marek

    2012-01-01

    Integration of metabolic and immune responses during animal development ensures energy balance, permitting both growth and defense. Disturbed homeostasis causes organ failure, growth retardation, and metabolic disorders. Here, we show that the Drosophila melanogaster activating transcription factor 3 (Atf3) safeguards metabolic and immune system homeostasis. Loss of Atf3 results in chronic inflammation and starvation responses mounted primarily by the larval gut epithelium, while the fat body suffers lipid overload, causing energy imbalance and death. Hyperactive proinflammatory and stress signaling through NF-κB/Relish, Jun N-terminal kinase, and FOXO in atf3 mutants deregulates genes important for immune defense, digestion, and lipid metabolism. Reducing the dose of either FOXO or Relish normalizes both lipid metabolism and gene expression in atf3 mutants. The function of Atf3 is conserved, as human ATF3 averts some of the Drosophila mutant phenotypes, improving their survival. The single Drosophila Atf3 may incorporate the diversified roles of two related mammalian proteins. PMID:22851689

  5. Platelet-activating factor-induced increases in glucose kinetics

    SciTech Connect

    Lang, C.H.; Dobrescu, C.; Hargrove, D.M.; Bagby, G.J.; Spitzer, J.J. )

    1988-02-01

    Platelet-activating factor (PAF) is a postulated mediator of many of the early hemodynamic effects of endotoxin. The aim of the present study was to determine whether in vivo administration of PAF could produce alterations in whole-body glucose metabolism that would mimic those seen during endotoxemia. Glucose kinetics were assessed in chronically catheterized conscious rats by the constant infusion of (6-{sup 3}H)- and (U-{sup 14}C)glucose before and for 4 h after either a bolus injection or a constant infusion of PAF. The bolus injection of PAF elevated the rate of glucose appearance (R{sub a}; 44%) for 1.5 h. The lower PAF infusion rate decreased blood pressure 11% to 104 mmHg, whereas the higher infusion rate decreased pressure 34% to 77 mmHg. Both PAF infusion rates produced elevations in plasma glucose and glucose R{sub a} throughout the 4-h infusion period in a dose-related manner. The PAF infusions also induced dose-related increases in plasma glucagon and catecholamine levels throughout the infusion period. Because the constant infusion of PAF did stimulate many of the hemodynamic and metabolic alterations produced by endotoxin, this study provides additional support for the potential importance of PAF as a mediator of the early hemodynamic and metabolic sequela of endotoxin shock. Furthermore, the PAF-induced changes in glucose metabolism appear to be mediated by the resultant elevation in plasma catecholamines.

  6. Influence of Environmental Factors on Feammox Activity in Soil Environments

    NASA Astrophysics Data System (ADS)

    Huang, S.; Jaffe, P. R.

    2015-12-01

    The oxidation of ammonium (NH4+) under iron reducing conditions, referred to as Feammox, has been described in recent years by several investigators. The environmental characteristics in which the Feammox process occurs need to be understood in order to determine its contribution to the nitrogen cycle. In this study, a total of 66 locations were selected covering 4 different types of soils/sediments: wetland soils (W), river sediments (R), forest soils (F), and paddy soils (P) from several locations in central New Jersey, at Tims Branch at Savannah River in South Carolina, both in the Unities States, and at several locations in the Guangdong province in China. Though soil chemical analyses, serial culturing experiments, analysis of microbial communities, and using a canonical correspondence analysis, the occurrence of the Feammox reaction and the presence of Acidimicrobiaceae bacterium A6, which plays a key role in the Feammox process(1), were found in 17 samples. Analyses showed that the soil pH, as well as its Fe(III) and NH4+ content were the most important factors controlling the distribution of these Feammox microorganisms. Based on the results, soils in the subtropical forests and soils that are near agricultural areas could be Feammox hotspot. Under the conditions that favor the presence and activity of Feammox microorganisms and their oxidation of NH4+, denitrification bacteria were also active. However, the presence of nitrous oxide (N2O) reducers was limited under these conditions, implying that at locations where the Feammox process is active, conditions are favoring a higher ratio of N2O: N2 as the nitrogen (N) end products. Incubations of soils where the presence of Acidimicrobiaceae bacterium A6 was detected, were conducted for 120 days under two different DO levels (DO < 0.02 mg/L and DO = 0.8~1.0 mg/L) showing comparable amounts of NH4+ oxidation. In the incubations with DO < 0.02 mg/L, the proportion of Acidimicrobiaceae bacteria increased and

  7. Oxidatively fragmented phosphatidylcholines activate human neutrophils through the receptor for platelet-activating factor.

    PubMed

    Smiley, P L; Stremler, K E; Prescott, S M; Zimmerman, G A; McIntyre, T M

    1991-06-15

    Platelet-activating factor (PAF, 1-O-alkyl-2-acetyl-sn-glycero-3-phosphocholine) activates neutrophils (polymorphonuclear leukocytes, PMN) through a receptor that specifically recognizes short sn-2 residues. We oxidized synthetic [2-arachidonoyl]phosphatidylcholine to fragment and shorten the sn-2 residue, and then examined the phospholipid products for the ability to stimulate PMN. 1-Palmitoyl-2-arachidonoyl-sn-glycero-3-phosphocholine was fragmented by ozonolysis to 1-palmitoyl-2-(5-oxovaleroyl)-sn-glycero-3-phosphocholine. This phospholipid activated human neutrophils at submicromolar concentrations, and is effects were inhibited by specific PAF receptor antagonists WEB2086, L659,989, and CV3988. 1-Palmitoyl-2-arachidonoyl-sn-glycero-3-phosphocholine next was fragmented by an uncontrolled free radical-catalyzed reaction: it was treated with soybean lipoxygenase to form its sn-2 15-hydroperoxy derivative (which did not activate neutrophils) and then allowed to oxidize under air. The secondary oxidation resulted in the formation of numerous fragmented phospholipids (Stremler, K. E., Stafforini, D. M., Prescott, S. M., and McIntyre, T. M. (1991) J. Biol. Chem. 266, 11095-11103), some of which activated PMN. Hydrolysis of sn-2 residues with phospholipase A2 destroyed biologic activity, as did hydrolysis with PAF acetylhydrolase. PAF acetylhydrolase is specific for short or intermediate length sn-2 residues and does not hydrolyze the starting material (Stremler, K. E., Stafforini, D. M., Prescott, S. M., and McIntyre, T. M. (1991) J. Biol. Chem. 266, 11095-11103). Neutrophil activation was completely blocked by L659,989, a specific PAF receptor antagonist. We conclude that diacylphosphatidylcholines containing an sn-2 polyunsaturated fatty acyl residue can be oxidatively fragmented to species with sn-2 residues short enough to activate the PAF receptor of neutrophils. This suggests a new mechanism for the appearance of biologically active phospholipids, and shows

  8. Intestinal alkaline sphingomyelinase hydrolyses and inactivates platelet-activating factor by a phospholipase C activity

    PubMed Central

    Wu, Jun; Nilsson, Åke; Jönsson, Bo A. G.; Stenstad, Hanna; Agace, William; Cheng, Yajun; Duan, Rui-Dong

    2005-01-01

    Alkaline sphingomyelinase (alk-SMase) is a new member of the NPP (nucleotide pyrophosphatase/phosphodiesterase) family that hydrolyses SM (sphingomyelin) to generate ceramide in the intestinal tract. The enzyme may protect the intestinal mucosa from inflammation and tumorigenesis. PAF (platelet-activating factor) is a pro-inflammatory phospholipid involved in pathogenesis of inflammatory bowel diseases. We examined whether alk-SMase can hydrolyse and inactivate PAF. [3H]Octadecyl-labelled PAF was incubated with purified rat intestinal alk-SMase or recombinant human alk-SMase expressed in COS-7 cells. The hydrolytic products were assayed with TLC and MS. We found that alkSMase cleaved the phosphocholine head group from PAF and generated 1-O-alkyl-2-acetyl-sn-glycerol. Differing from the activity against SM, the activity against PAF was optimal at pH 7.5, inhibited by EDTA and stimulated by 0.1–0.25 mM Zn2+. The activity was abolished by site mutation of the predicted metal-binding sites that are conserved in all NPP members. Similar to the activity against SM, the activity against PAF was dependent on bile salt, particularly taurocholate and taurochenodeoxycholate. The Vmax for PAF hydrolysis was 374 μmol·h−1·(mg of protein)−1. The hydrolysis of PAF and SM could be inhibited by the presence of SM and PAF respectively, the inhibition of PAF hydrolysis by SM being stronger. The PAF-induced MAPK (mitogen-activated protein kinase) activation and IL-8 (interleukin 8) release in HT-29 cells, and chemotaxis in leucocytes were abolished by alk-SMase treatment. In conclusion, alk-SMase hydrolyses and inactivates PAF by a phospholipase C activity. The finding reveals a novel function, by which alk-SMase may counteract the development of intestinal inflammation and colon cancer. PMID:16255717

  9. Stimulation of Leishmania tropica protein kinase CK2 activities by platelet-activating factor (PAF).

    PubMed

    Dutra, Patricia M L; Vieira, Danielle P; Meyer-Fernandes, Jose R; Silva-Neto, Mario A C; Lopes, Angela H

    2009-09-01

    Leishmania tropica is one of the causative agents of cutaneous leishmaniasis. Platelet-activating factor (PAF) is a phospholipid mediator in diverse biological and pathophysiological processes. Here we show that PAF promoted a three-fold increase on ecto-protein kinase and a three-fold increase on the secreted kinase activity of L. tropica live promastigotes. When casein was added to the reaction medium, along with PAF, there was a four-fold increase on the ecto-kinase activity. When live L. tropica promastigotes were pre-incubated for 30 min in the presence of PAF-plus casein, a six-fold increase on the secreted kinase activity was observed. Also, a protein released from L. tropica promastigotes reacted with polyclonal antibodies for the mammalian CK2 alpha catalytic subunit. Furthermore, in vitro mouse macrophage infection by L. tropica was doubled when promastigotes were pre-treated for 2 h with PAF. Similar results were obtained when the interaction was performed in the presence of purified CK2 or casein. TBB and DRB, CK2 inhibitors, reversed PAF enhancement of macrophage infection by L. tropica. WEB 2086, a competitive PAF antagonist, reversed all PAF effects here described. This study shows for the first time that PAF promotes the activation of two isoforms of CK2, secreted and membrane-bound, correlating these activities to infection of mouse macrophages.

  10. Loss of factor VIII activity during storage in PVC containers due to adsorption.

    PubMed

    McLeod, A G; Walker, I R; Zheng, S; Hayward, C P

    2000-03-01

    Recombinant factor VIII concentrates are stable when administered in a reconstituted form according to the manufacturer's specifications, and undiluted via infusion with syringe mini-pumps. However many Haemophilia centres administer recombinant factor VIII further diluted in intravenous fluids for greater ease of administration. To investigate the stability of recombinant factor VIII during administration as a diluted infusion, reconstituted factor VIII was stored in polyvinylchloride (PVC) mini-bags undiluted (146 IU mL-1) and at factor VIII concentrations of 10 IU mL-1 and 2 IU mL-1. After 48 h of storage at room temperature in PVC mini-bags, the recoveries of factor VIII activity were 41.9% of the initial activity for the undiluted (146 IU mL-1) product and 43.7% of the initial activity for factor VIII diluted to 10 IU mL-1. For factor VIII diluted to 2 IU mL-1, the amount of factor VIII activity remaining at 48 h was only 1.8% of the initial activity. In contrast, 100% of factor VIII activity was recovered after 48 h when undiluted reconstituted product (146 IU mL-1) was stored in a syringe. To investigate the mechanism of factor VIII activity loss during storage, factor VIII samples collected after 0, 3 and 48 h of storage were analysed by immunoblotting with factor VIII antibodies. No evidence of factor VIII proteolytic degradation during storage was found, however, large amounts of factor VIII antigen were recovered from the empty PVC mini-bags following elution with denaturing detergent. We conclude that clinically significant losses of factor VIII activity occur during storage in PVC mini-bags and that the loss of activity is most likely due to protein adsorption onto the plastic surface. This loss of factor VIII activity during storage in PVC containers may substantially affect the safety and potential cost savings of administering recombinant factor VIII by continuous infusion.

  11. Shedding of tumor necrosis factor receptors by activated human neutrophils

    PubMed Central

    1990-01-01

    The capacity of human neutrophils (PMN) to bind tumor necrosis factor (TNF) was rapidly lost when the cells were incubated in suspension with agents that can stimulate their migratory and secretory responses. Both physiological (poly)peptides (FMLP, C5a, CSF-GM) and pharmacologic agonists (PMN, calcium ionophore A23187) induced the loss of TNF receptors (TNF-R) from the cell surface. Half-maximal loss in TNF-R ensued after only approximately 2 min with 10(-7) M FMLP at 37 degrees C, and required only 10(-9) M FMLP during a 30-min exposure. However, there were no such changes even with prolonged exposure of PMN to FMLP at 4 degrees or 16 degrees C. Scatchard analysis revealed loss of TNF- binding sites without change in their affinity (Kd approximately 0.4 nM) as measured at incompletely modulating concentrations of FMLP, C5a, PMA, or A23187. The binding of anti-TNF-R mAbs to PMN decreased in parallel, providing independent evidence for the loss of TNF-R from the cell surface. At the same time, soluble TNF-R appeared in the medium of stimulated PMN. This inference was based on the PMN- and FMLP-dependent generation of a nonsedimentable activity that could inhibit the binding of TNF to fresh human PMN or to mouse macrophages, and the ability of mAbs specific for human TNF-R to abolish inhibition by PMN-conditioned medium of binding of TNF to mouse macrophages. Soluble TNF-R activity was associated with a protein of Mr approximately 28,000 by ligand blot analysis of cell-free supernatants of FMLP-treated PMN. Thus, some portion of the FMLP-induced loss of TNF-R from human PMN is due to shedding of TNF-R. Shedding was unaffected by inhibitors of serine and thiol proteases and could not be induced with phosphatidylinositol- specific phospholipase C. Loss of TNF-R from PMN first stimulated by other agents may decrease their responsiveness to TNF. TNF-R shed by PMN may be one source of the TNF-binding proteins found in body fluids, and may blunt the actions of the

  12. Platelet activating factor raises intracellular calcium ion concentration in macrophages

    PubMed Central

    1986-01-01

    Peritoneal cells from thioglycollate-stimulated mice were allowed to adhere to coverglasses for 2 h to give a dense monolayer of adherent cells greater than 95% of which were macrophages. After incubation with the tetra-acetoxymethyl ester of quin2, coverglasses were rinsed with Ca2+-free saline, oriented at a 45 degree angle in square cuvettes containing a magnetically driven stir bar, and analyzed for changes in quin2 fluorescence in a spectrofluorimeter. Such fluorescence, taken as an indication of intracellular calcium ion concentration ([Ca2+]i), increased as exogenous calcium ion concentration ([Ca2+]o) was raised to 1 mM. At [Ca2+]o approximately equal to 10 microM, [Ca2+]i = 72 +/- 14 nM (n = 26); at [Ca2+]o = 1 mM, [Ca2+]i = 140-220 nM, levels not increased by N, N, N', N'-tetrakis (2-pyridylmethyl) ethylenediamine, a membrane-permeant chelator of heavy metals than can quench quin2. Addition of mouse alpha + beta fibroblast interferon, lipopolysaccharide, thrombin, collagen, vasopressin, ADP, compound 48/80, or U46619 did not change [Ca2+]i. However, addition of platelet activating factor (PAF) (2-20 ng/ml) raised [Ca2+]i by 480 nM within 1 min if [Ca2+]o = 1 mM. In the presence of 5 mM EGTA, PAF raised [Ca2+]i by 25 nM. This suggests that PAF causes influx of exogenous Ca2+, as well as releasing some Ca2+ from intracellular stores. Consistent with these results, when PAF was added to 1 mM Ca2+ in the presence of 100 microM Cd2+ or Mn2+ to block Ca2+ influx, [Ca2+]i increased by only intermediate amounts; at the times of such dampened peak response, [Ca2+]i could be raised within 1 min to normal PAF-stimulated levels by chelation of the exogenous heavy metals with diethylenetriaminepentaacetic acid. Normal PAF responses were observed in the presence of indomethacin. The lowest dose of PAF observed to raise [Ca2+]i was 0.1 ng/ml. Response of [Ca2+]i to 2-20 ng/ml PAF was transient, and second applications had no effect. The PAF response also was seen in

  13. Activation of G Proteins by Guanine Nucleotide Exchange Factors Relies on GTPase Activity

    PubMed Central

    Stanley, Rob J.; Thomas, Geraint M. H.

    2016-01-01

    G proteins are an important family of signalling molecules controlled by guanine nucleotide exchange and GTPase activity in what is commonly called an ‘activation/inactivation cycle’. The molecular mechanism by which guanine nucleotide exchange factors (GEFs) catalyse the activation of monomeric G proteins is well-established, however the complete reversibility of this mechanism is often overlooked. Here, we use a theoretical approach to prove that GEFs are unable to positively control G protein systems at steady-state in the absence of GTPase activity. Instead, positive regulation of G proteins must be seen as a product of the competition between guanine nucleotide exchange and GTPase activity—emphasising a central role for GTPase activity beyond merely signal termination. We conclude that a more accurate description of the regulation of G proteins via these processes is as a ‘balance/imbalance’ mechanism. This result has implications for the understanding of intracellular signalling processes, and for experimental strategies that rely on modulating G protein systems. PMID:26986850

  14. Lethal Factor Active-Site Mutations Affect Catalytic Activity In Vitro

    PubMed Central

    Hammond, S. E.; Hanna, P. C.

    1998-01-01

    The lethal factor (LF) protein of Bacillus anthracis lethal toxin contains the thermolysin-like active-site and zinc-binding consensus motif HEXXH (K. R. Klimpel, N. Arora, and S. H. Leppla, Mol. Microbiol. 13:1093–1100, 1994). LF is hypothesized to act as a Zn2+ metalloprotease in the cytoplasm of macrophages, but no proteolytic activities have been previously shown on any target substrate. Here, synthetic peptides are hydrolyzed by LF in vitro. Mass spectroscopy and peptide sequencing of isolated cleavage products separated by reverse-phase high-pressure liquid chromatography indicate that LF seems to prefer proline-containing substrates. Substitution mutations within the consensus active-site residues completely abolish all in vitro catalytic functions, as does addition of 1,10-phenanthroline, EDTA, and certain amino acid hydroxamates, including the novel zinc metalloprotease inhibitor ZINCOV. In contrast, the protease inhibitors bestatin and lysine CMK, previously shown to block LF activity on macrophages, did not block LF activity in vitro. These data provide the first direct evidence that LF may act as an endopeptidase. PMID:9573135

  15. Tumor necrosis factor-inducing activities of Cryptococcus neoformans components.

    PubMed Central

    Delfino, D; Cianci, L; Migliardo, M; Mancuso, G; Cusumano, V; Corradini, C; Teti, G

    1996-01-01

    Cryptococcus neoformans-induced tumor necrosis factor alpha (TNF-alpha) production may lead to increased human immunodeficiency virus replication in patients with AIDS. In order to identify cryptococcal components that are predominantly responsible for stimulating TNF production, various concentrations of glucuronoxylomannan (GXM), galactoxylomannan (GalXM), mannoproteins (MP), and alpha(1-3) [corrected] glucan were added to whole-blood cultures. All of the cryptococcal components tested, as well as whole heat-killed cryptococci, were capable of inducing TNF-alpha release in a dose-dependent manner. MP were significantly more potent than any of the other cryptococcal components tested or heat-killed cryptococci in stimulating TNF-alpha production (P < 0.05). GXM, in contrast, was significantly less potent in this activity than either GalXM or MP (P < 0.05). As little as 0.5 microg of MP per ml was sufficient to produce moderate but significant elevations of TNF-alpha release. Maximal MP-induced TNF-alpha levels were similar to those induced by Salmonella enteritidis lipopolysaccharide, our positive control. Further experiments using isolated leukocytes suggested that monocytes were the cell population mainly responsible for TNF-alpha production, although the participation of other cell types could not be excluded. The presence of complement-sufficient plasma was a necessary requirement for TNF-alpha induction by GXM, GalXM, and low doses of MP. High MP concentrations (100 microg/ml) were also capable of stimulating TNF-alpha production in the absence of plasma. These data indicate that soluble products released by C. neoformans are capable of inducing TNF-alpha secretion in human leukocytes. This may be clinically relevant, since high concentrations of such products are frequently found in the body fluids of AIDS patients infected with C. neoformans. PMID:8945566

  16. Mobilization of hepatic calcium pools by platelet activating factor

    SciTech Connect

    Lapointe, D.S.; Hanahan, D.J.; Olson, M.S.

    1987-03-24

    In the perfused rat liver, platelet activating factor, 1-O-hexadecyl-2-acetyl-sn-glycero-3-phosphocholine (AGEPC), infusion produces an extensive but transient glycogenolytic response which at low AGEPC concentrations is markedly dependent upon the perfusate calcium levels. The role of calcium in the glycogenolytic response of the liver to AGEPC was investigated by assessing the effect of AGEPC on various calcium pools in the intact liver. Livers from fed rats were equilibrated with /sup 45/Ca/sup 2 +/, and the kinetics of /sup 45/Ca/sup 2 +/ efflux were determined in control, AGEPC-stimulated, and phenylephrine-stimulated livers during steady-state washout of /sup 45/Ca/sup 2 +/. AGEPC treatment had only a slight if any effect on the pattern of steady-state calcium efflux from the liver, as opposed to major perturbations in the pattern of calcium efflux effected by the ..cap alpha..-adrenergic agonist phenylephrine. Infusion of short pulses of AGEPC during the washout of /sup 45/Ca/sup 2 +/ from labeled livers caused a transient release of /sup 45/Ca/sup 2 +/ which was not abolished at low calcium concentrations in the perfusate. Infusion of latex beads, which are removed by the reticuloendothelial cells, caused the release of hepatic /sup 45/Ca/sup 2 +/ in a fashion similar to the case with AGEPC. The findings indicate that AGEPC does not perturb a major pool of calcium within the liver as occurs upon ..cap alpha..-adrenergic stimulation; it is likely that AGEPC mobilizes calcium from a smaller yet very important pool, very possibly from nonparenchymal cells in the liver.

  17. Local anesthetics inhibit tissue factor expression in activated monocytes via inhibition of tissue factor mRNA synthesis.

    PubMed

    Kim, Ji-Eun; Kim, Ki Jun; Ahn, Wonsik; Han, Kyou-Sup; Kim, Hyun Kyung

    2011-01-01

    Local anesthetics have been reported to have anticoagulant properties, but the mechanisms responsible for this action are poorly understood. Here, we evaluated the in vitro effects of 3 local anesthetics--lidocaine, ropivacaine, and bupivacaine--on the tissue factor expression by monocytes. Monocytes from peripheral blood were stimulated with lipopolysaccharide (LPS) in the presence or absence of local anesthetics. All 3 local anesthetics inhibited the expression of tissue factor antigen and tissue factor activity in LPS-stimulated monocytes in a dose- and time-dependent manner and reduced tissue factor messenger RNA (mRNA) expression in endothelial cells and a monocytic cell line. None of the 3 drugs induced apoptosis or affected the viability of monocytes. Our findings that local anesthetics inhibited the tissue factor induction in activated monocytes by inhibiting tissue factor mRNA level may demonstrate the feasibility of using local anesthetics in hypercoagulable and inflammatory conditions.

  18. The essential activities of the bacterial sigma factor.

    PubMed

    Davis, Maria C; Kesthely, Christopher A; Franklin, Emily A; MacLellan, Shawn R

    2017-02-01

    Transcription is the first and most heavily regulated step in gene expression. Sigma (σ) factors are general transcription factors that reversibly bind RNA polymerase (RNAP) and mediate transcription of all genes in bacteria. σ Factors play 3 major roles in the RNA synthesis initiation process: they (i) target RNAP holoenzyme to specific promoters, (ii) melt a region of double-stranded promoter DNA and stabilize it as a single-stranded open complex, and (iii) interact with other DNA-binding transcription factors to contribute complexity to gene expression regulation schemes. Recent structural studies have demonstrated that when σ factors bind promoter DNA, they capture 1 or more nucleotides that are flipped out of the helical DNA stack and this stabilizes the promoter open-complex intermediate that is required for the initiation of RNA synthesis. This review describes the structure and function of the σ(70) family of σ proteins and the essential roles they play in the transcription process.

  19. Plasma ADAMTS13 activity and von Willebrand Factor Antigen and Activity In Patients with Subarachnoid Hemorrhage

    PubMed Central

    Kumar, Monisha; Cao, Wenjing; McDaniel, Jenny K.; Pham, Huy P.; Raju, Dheeraj; Nawalinski, Kelsey; Frangos, Suzanne; Kung, David; Zager, Eric E.; Kasner, Scott E.; Levine, Joshua M.; Zheng, X. Long

    2017-01-01

    Summary Background Increased von Willebrand factor (VWF) and reduced ADAMTS13 activity are associated with arterial thrombosis. This may also be the culprit mechanism implicated in delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage (SAH). Objective To determine plasma VWF and ADAMTS13 in patients with SAH and healthy subjects; and to explore the levels of those markers and outcome after SAH. Methods 40 consecutive patients were enrolled between September 2007 and April 2014 in a pilot study. Plasma samples were collected from SAH patients on post-bleed day (PBD) 0, 1, 3, 5, 7 and 10 and healthy controls. VWF antigen (VWFAg) and VWF activity (VWFAc) were determined by enzyme-linked immunoassay and collagen binding assay, respectively. ADAMTS13 activity was determined by the cleavage of a fluorescent substrate. Univariate descriptive statistics and cluster analyses were performed based on outcomes in the group with SAH only. Results Mean age of SAH patients was 52.4 years (26–84 years) and 30 (75%) were women. 12/40 (30%) had a high Hunt and Hess grade (IV–V) and 25 (62.5%) were treated with coil embolization. Plasma VWFAg and VWFAc were significantly higher in SAH patients than those in healthy subjects on each PBD (p<0.0001). Concurrently, plasma ADAMTS13 activity in SAH patients was significantly lower than that in healthy subjects (p<0.0001). Among those with SAH, cluster analysis demonstrated that patients with higher VWFAg and VWFAc and/or lower ADAMTS13 activity might be at risk of increased mortality. Conclusions The relative deficiency of plasma ADAMTS13 activity in SAH patients may associate with worse outcome. PMID:28102428

  20. Plasma ADAMTS13 activity and von Willebrand factor antigen and activity in patients with subarachnoid haemorrhage.

    PubMed

    Kumar, Monisha; Cao, Wenjing; McDaniel, Jenny K; Pham, Huy P; Raju, Dheeraj; Nawalinski, Kelsey; Frangos, Suzanne; Kung, David; Zager, Eric; Kasner, Scott E; Levine, Joshua M; Zheng, X Long

    2017-01-19

    Increased von Willebrand factor (VWF) and reduced ADAMTS13 activity are associated with arterial thrombosis. This may also be the culprit mechanism implicated in delayed cerebral ischaemia after aneurysmal subarachnoid haemorrhage (SAH). It was our objective to determine plasma VWF and ADAMTS13 in patients with SAH and healthy subjects; and to explore the levels of those markers and outcome after SAH. Forty consecutive patients were enrolled between September 2007 and April 2014 in a pilot study. Plasma samples were collected from SAH patients on post-bleed day (PBD) 0, 1, 3, 5, 7 and 10 and healthy controls. VWF antigen (VWFAg) and VWF activity (VWFAc) were determined by enzyme-linked immunoassay and collagen binding assay, respectively. ADAMTS13 activity was determined by the cleavage of a fluorescent substrate. Univariate descriptive statistics and cluster analyses were performed based on outcomes in the group with SAH only. Mean age of SAH patients was 52.4 years (26-84 years) and 30 (75 %) were women. 12/40 (30 %) had a high Hunt and Hess grade (IV-V) and 25 (62.5 %) were treated with coil embolisation. Plasma VWFAg and VWFAc were significantly higher in SAH patients than those in healthy subjects on each PBD (p<0.0001). Concurrently, plasma ADAMTS13 activity in SAH patients was significantly lower than that in healthy subjects (p<0.0001). Among those with SAH, cluster analysis demonstrated that patients with higher VWFAg and VWFAc and/or lower ADAMTS13 activity might be at risk of increased mortality. In conclusion, the relative deficiency of plasma ADAMTS13 activity in SAH patients may associate with worse outcome.

  1. The Role of TLR4 on B Cell Activation and Anti-β2GPI Antibody Production in the Antiphospholipid Syndrome

    PubMed Central

    2016-01-01

    High titer of anti-β2-glycoprotein I antibodies (anti-β2GPI Ab) plays a pathogenic role in antiphospholipid syndrome (APS). Numerous studies have focused on the pathological mechanism in APS; however, little attention is paid to the immune mechanism of production of anti-β2GPI antibodies in APS. Our previous study demonstrated that Toll-like receptor 4 (TLR4) plays a vital role in the maturation of bone marrow-derived dendritic cells (BMDCs) from the mice immunized with human β2-glycoprotein I (β2GPI). TLR4 is required for the activation of B cells and the production of autoantibody in mice treated with β2GPI. However, TLR4 provides a third signal for B cell activation and then promotes B cells better receiving signals from both B cell antigen receptor (BCR) and CD40, thus promoting B cell activation, surface molecules expression, anti-β2GPI Ab production, and cytokines secretion and making B cell functioning like an antigen presenting cell (APC). At the same time, TLR4 also promotes B cells producing antibodies by upregulating the expression of B-cell activating factor (BAFF). In this paper, we aim to review the functions of TLR4 in B cell immune response and antibody production in autoimmune disease APS and try to find a new way for the prevention and treatment of APS. PMID:27868072

  2. 75 FR 80114 - Agency Information Collection (Obligation To Report Factors Affecting Entitlement) Activity Under...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-21

    ... AFFAIRS Agency Information Collection (Obligation To Report Factors Affecting Entitlement) Activity Under... INFORMATION: Title: Obligation to Report Factors Affecting Entitlement (38 CFR 3.204(a)(1), 38 CFR 3.256(a... compensation benefits must report changes in their entitlement factors. Individual factors such as...

  3. Alternative pathways of thromboplastin-dependent activation of human factor X in plasma

    SciTech Connect

    Marlar, R.A.; Griffin, J.H.

    1981-01-01

    To determine the interrelationships of the major coagulation pathways, the activation of 3H-labeled factor X in normal and various deficient human plasmas was evaluated when clotting was triggered by dilute rabbit or human thromboplastin. Various dilutions of thromboplastin and calcium were added to plasma samples containing 3H-factor X, and the time course of factor X activation was determined. At a 1/250 dilution of rabbit brain thromboplastin, the rate of factor X activation in plasmas deficient in factor VIII or factor IX was 10% of the activation rate of normal plasma or of factor XI deficient plasma. Reconstitution of the deficient plasmas with factors VIII or IX, respectively, reconstituted normal factor X activation. Similar results were obtained when various dilutions of human thromboplastin replaced the rabbit thromboplastin. From these plasma experiments, it is inferred that the dilute thromboplastin-dependent activation of factor X requires factors VII, IX, and VIII. An alternative extrinsic pathway that involves factors IX and VIII may be the physiologic extrinsic pathway and hence help to explain the consistent clinical observations of bleeding diatheses in patients deficient in factors IX or VIII.

  4. Inhibition of the activation of Hageman factor (factor XII) and of platelet aggregation by extracts of Brugia malayi microfilariae.

    PubMed

    Foster, C B; Flanigan, T P; Kazura, J W; Dumenco, L L; Ratnoff, O D

    1991-05-01

    In human filariasis, large numbers of blood-borne microfilariae circulate unimpeded through the blood stream. How intravascular filarial parasites avoid precipitating thrombosis has not been studied in detail. We hypothesized that extracts of Brugia malayi microfilariae would contain factors that inhibit activation of hemostatic mechanisms. Initial studies demonstrated an inhibitor specific for the intrinsic coagulation cascade. The addition of microfilarial extracts to human plasma prolonged the activated partial thromboplastin time in a dose-dependent fashion but did not prolong the prothrombin, thrombin, or Russell's viper venom times. Microfilarial extracts (0.1 mg/ml) completely inhibited activation of Hageman factor (factor XII, at 0.05 U/ml) as measured in an amidolytic assay. Hageman factor previously activated by ellagic acid (factor XIIa) retained full enzymatic activity in the presence of microfilarial extract (0.1 mg/ml). The presence of inhibitory activity in the culture medium of live parasites raises the possibility that microfilariae secrete an inhibitory protein into their local environment. Microfilarial extracts at a final concentration of 0.1 mg/ml also inhibited collagen- and adenosine diphosphate-induced platelet aggregation. Arachidonic acid-induced platelet aggregation was inhibited by microfilarial extracts at a final concentration of 0.6 mg/ml. These results suggest that microfilariae of Brugia malayi, a human filarial parasite, may avoid initiating thrombosis through inhibition of the intrinsic coagulation pathway and platelet aggregation.

  5. Transforming growth factor-beta induces endothelin-1 expression through activation of the Smad signaling pathway.

    PubMed

    Rodríguez-Pascual, Fernando; Reimunde, Francisco Manuel; Redondo-Horcajo, Mariano; Lamas, Santiago

    2004-11-01

    Expression of the endothelin-1 gene is subject to complex regulation by different factors, among which transforming growth factor-beta is one of the most important. We have analyzed the mechanism by which transforming growth factor-beta increases endothelin-1 expression in vascular endothelial cells. Transcriptional activation of the endothelin-1 promoter accounted for the transforming growth factor-beta-induced increase in endothelin-1 mRNA levels. Two DNA elements within the promoter are responsible for this effect: a Smad binding element and a proximal activator protein-1 site. Mutation of both elements abolished transforming growth factor-beta responsiveness. Overexpression of the Smad3 isoform strongly potentiates transforming growth factor-beta- induced endothelin-1 promoter activity in a phosphorylation-dependent manner. These results demonstrate that transforming growth factor-beta induces endothelin-1 expression by a functional cooperation between Smads and activator protein-1 through activation of the Smad signaling pathway.

  6. Effect of boar seminal plasma immunosuppressive factor on NK cell activity and skin graft survival.

    PubMed

    Veselsky, L; Holan, V; Soucek, J; Stanek, R; Hoskova, M

    1992-01-01

    The B 10 strain of mice was used to test the effect of the boar seminal vesicle immunosuppressive factor on the female mouse response to the male-specific transplantation antigen. Influence of this factor on human natural killer (NK) cell activity was also studied. No inhibitory effect of the immunosuppressive factor on graft survival was apparent during a time of more than 200 days, nor did the factor suppress NK cell activity.

  7. Non-redundant and complementary functions of adaptor proteins TRAF2 and TRAF3 in a ubiquitination cascade that activates NIK-dependent alternative NF-κB signaling

    PubMed Central

    Vallabhapurapu, Sivakumar; Matsuzawa, Atsushi; Zhang, WeiZhou; Tseng, Ping-Hui; Keats, Jonathan J.; Wang, Haopeng; Vignali, Dario A. A.; Bergsagel, P. Leif; Karin, Michael

    2009-01-01

    The adaptor and signaling proteins TRAF2, TRAF3 and cIAP1 and cIAP2 were suggested to inhibit alternative nuclear factor kappa B (NF-κB) signaling in resting cells by targeting NF-κB inducing kinase (NIK) to ubiquitin-dependent degradation, thus preventing processing of the NF-κB2 precursor protein p100 to release p52. However, the respective functions of TRAF2 and TRAF3 in NIK degradation and activation of alternative NF-κB signaling has remained elusive. We now show that CD40 or BAFF receptor activation resulted in TRAF3 degradation in a cIAP1-cIAP2- and TRAF2- dependent way due to enhanced cIAP1, cIAP2 TRAF3-directed ubiquitin ligase activity. Receptor-induced activation of cIAP1 and cIAP2 correlated with their K63-linked ubiquitination by TRAF2. Degradation of TRAF3 prevented association of NIK with the cIAP1-cIAP2-TRAF2 ubiquitin ligase complex, which resulted in NIK stabilization and NF-κB2-p100 processing. Constitutive activation of this pathway causes perinatal lethality and lymphoid defects. PMID:18997792

  8. Social and Environmental Factors Associated with Preschoolers' Nonsedentary Physical Activity

    ERIC Educational Resources Information Center

    Brown, William H.; Pfeiffer, Karin A.; McIver, Kerry L.; Dowda, Marsha; Addy, Cheryl L.; Pate, Russell R.

    2009-01-01

    The twofold purposes of the investigation were (a) to describe with direct observation data the physical activity behaviors and the accompanying social and environmental events of those behaviors for children in preschools and (b) to determine which contextual conditions were predictors of moderate to vigorous physical activity (MVPA) and…

  9. Physical Activity among Older People and Related Factors

    ERIC Educational Resources Information Center

    Persson, Ann; While, Alison

    2012-01-01

    Objective: To investigate the duration, intensity and type of physical activity undertaken by people aged 60 years and over in relation to their reported levels of participation in social activities and their perceptions of their neighbourhood. Design: A cross-sectional questionnaire survey of older people attending two luncheon and eight social…

  10. Factors Shaping Students' Opportunities to Engage in Argumentative Activity

    ERIC Educational Resources Information Center

    Ayalon, Michal; Even, Ruhama

    2016-01-01

    This study examines how students' opportunities to engage in argumentative activity are shaped by the teacher, the class, and the mathematical topic. It compares the argumentative activity between two classes taught by the same teacher using the same textbook and across two beginning algebra topics--investigating algebraic expressions and…

  11. FBXO10 deficiency and BTK activation upregulate BCL2 expression in mantle cell lymphoma

    PubMed Central

    Li, Y; Bouchlaka, MN; Wolff, J; Grindle, KM; Lu, L; Qian, S; Zhong, X; Pflum, N; Jobin, P; Kahl, BS; Eickhoff, JC; Wuerzberger-Davis, SM; Miyamoto, S; Thomas, CJ; Yang, DT; Capitini, CM; Rui, L

    2016-01-01

    Targeting Bruton tyrosine kinase (BTK) by ibrutinib is an effective treatment for patients with relapsed/refractory mantle cell lymphoma (MCL). However, both primary and acquired resistance to ibrutinib have developed in a significant number of these patients. A combinatory strategy targeting multiple oncogenic pathways is critical to enhance the efficacy of ibrutinib. Here, we focus on the BCL2 anti-apoptotic pathway. In a tissue microarray of 62 MCL samples, BCL2 expression positively correlated with BTK expression. Increased levels of BCL2 were shown to be due to a defect in protein degradation because of no or little expression of the E3 ubiquitin ligase FBXO10, as well as transcriptional upregulation through BTK-mediated canonical nuclear factor-κB activation. RNA-seq analysis confirmed that a set of anti-apoptotic genes (for example, BCL2, BCL-XL and DAD1) was downregulated by BTK short hairpin RNA. The downregulated genes also included those that are critical for B-cell growth and proliferation, such as BCL6, MYC, PIK3CA and BAFF-R. Targeting BCL2 by the specific inhibitor ABT-199 synergized with ibrutinib in inhibiting growth of both ibrutinib-sensitive and -resistant cancer cells in vitro and in vivo. These results suggest co-targeting of BTK and BCL2 as a new therapeutic strategy in MCL, especially for patients with primary resistance to ibrutinib. PMID:27157620

  12. Building gene expression signatures indicative of transcription factor activation to predict AOP modulation

    EPA Science Inventory

    Building gene expression signatures indicative of transcription factor activation to predict AOP modulation Adverse outcome pathways (AOPs) are a framework for predicting quantitative relationships between molecular initiatin...

  13. Resveratrol Enhances Antitumor Activity of TRAIL in Prostate Cancer Xenografts through Activation of FOXO Transcription Factor

    PubMed Central

    Ganapathy, Suthakar; Chen, Qinghe; Singh, Karan P.; Shankar, Sharmila; Srivastava, Rakesh K.

    2010-01-01

    Background Resveratrol (3, 4′, 5 tri-hydroxystilbene), a naturally occurring polyphenol, exhibits anti-inflammatory, antioxidant, cardioprotective and antitumor activities. We have recently shown that resveratrol can enhance the apoptosis-inducing potential of TRAIL in prostate cancer cells through multiple mechanisms in vitro. Therefore, the present study was designed to validate whether resveratrol can enhance the apoptosis-inducing potential of TRAIL in a xenograft model of prostate cancer. Methodology/Principal Findings Resveratrol and TRAIL alone inhibited growth of PC-3 xenografts in nude mice by inhibiting tumor cell proliferation (PCNA and Ki67 staining) and inducing apoptosis (TUNEL staining). The combination of resveratrol and TRAIL was more effective in inhibiting tumor growth than single agent alone. In xenografted tumors, resveratrol upregulated the expressions of TRAIL-R1/DR4, TRAIL-R2/DR5, Bax and p27/K IP1, and inhibited the expression of Bcl-2 and cyclin D1. Treatment of mice with resveratrol and TRAIL alone inhibited angiogenesis (as demonstrated by reduced number of blood vessels, and VEGF and VEGFR2 positive cells) and markers of metastasis (MMP-2 and MMP-9). The combination of resveratrol with TRAIL further inhibited number of blood vessels in tumors, and circulating endothelial growth factor receptor 2-positive endothelial cells than single agent alone. Furthermore, resveratrol inhibited the cytoplasmic phosphorylation of FKHRL1 resulting in its enhanced activation as demonstrated by increased DNA binding activity. Conclusions/Significance These data suggest that resveratrol can enhance the apoptosis-inducing potential of TRAIL by activating FKHRL1 and its target genes. The ability of resveratrol to inhibit tumor growth, metastasis and angiogenesis, and enhance the therapeutic potential of TRAIL suggests that resveratrol alone or in combination with TRAIL can be used for the management of prostate cancer. PMID:21209944

  14. Coexpression of heparanase activity, cathepsin L, tissue factor, tissue factor pathway inhibitor, and MMP-9 in proliferative diabetic retinopathy

    PubMed Central

    Siddiquei, Mohammad Mairaj; Nawaz, Mohd Imtiaz; De Hertogh, Gert; Mohammad, Ghulam; Alam, Kaiser; Mousa, Ahmed; Opdenakker, Ghislain

    2016-01-01

    Purpose Heparanase cleaves heparan sulfate side chains of heparan sulfate proteoglycans, activity that is implicated in angiogenesis. Proteolytic cleavage of proheparanase by cathepsin L leads to the formation of catalytically active heparanase. We investigated the expression levels of heparanase enzymatic activity and correlated these with the levels of cathepsin L, the angiogenic factors tissue factor (TF) and matrix metalloproteinase-9 (MMP-9), and the angiostatic factor tissue factor pathway inhibitor (TFPI) in proliferative diabetic retinopathy (PDR). Methods Vitreous samples from 25 patients with PDR and 20 nondiabetic patients and epiretinal membranes from 12 patients with PDR were studied with enzyme-linked immunosorbent assay, western blot analysis, and immunohistochemistry. Results We observed a significant increase in the expression of heparanase activity in vitreous samples from patients with PDR compared to the nondiabetic controls (p=0.027). Significant positive correlations were found between the levels of heparanase activity and the levels of cathepsin L (r=0.51; p=0.001), TF (r=0.6; p<0.0001), and TFPI (r=0.49; p=0.001). The expression levels of cathepsin L (p=0.019), TF (p<0.0001), TFPI (p<0.0001), and MMP-9 (p=0.029) were significantly higher in the vitreous samples with detected heparanase activity compared to the vitreous samples with undetected heparanase activity. Western blot analysis demonstrated proteolytic cleavage of TFPI in the vitreous samples from patients with PDR. In the epiretinal membranes, cathepsin L, TF, and TFPI were expressed in vascular endothelial cells and CD45-expressing leukocytes. Significant positive correlations were detected between the number of blood vessels that expressed CD31 and the number of blood vessels that expressed TF (r=0.9; p<0.0001) and TFPI (r=0.81; p=0.001). Conclusions The coexpression of these angiogenesis regulatory factors suggests cross-talk between these factors and pathogenesis of PDR

  15. Impact of nonsynonymous mutations of factor X on the functions of factor X and anticoagulant activity of edoxaban.

    PubMed

    Noguchi, Kengo; Morishima, Yoshiyuki; Takahashi, Shinichi; Ishihara, Hiroaki; Shibano, Toshiro; Murata, Mitsuru

    2015-03-01

    Edoxaban is an oral direct factor Xa (FXa) inhibitor and its efficacy as an oral anticoagulant is less subject to drug-food and drug-drug interaction than existing vitamin K antagonists. Although this profile of edoxaban suggests it is well suited for clinical use, it is not clear whether genetic variations of factor X influence the activity of edoxaban. Our aim was to investigate a possible impact of single-nucleotide polymorphisms (SNPs) in the factor X gene on the functions of factor X and the activity of edoxaban. Two nonsynonymous SNPs within mature factor X, Ala152Thr and Gly192Arg, were selected as possible candidates that might affect the functions of FXa and the activity of edoxaban. We measured catalytic activities of wild type and mutant FXas in a chromogenic assay using S-2222 and coagulation times including prothrombin time (PT) and activated partial thrombin time (aPTT) of plasma-containing recombinant FXs in the presence and absence of edoxaban. Michaelis-Menten kinetic parameters of FXas, Km and Vmax values, PT and aPTT were not influenced by either mutation indicating these mutations do not affect the FXa catalytic and coagulation activities. The Ki values of edoxaban for the FXas and the concentrations of edoxaban required to double PT and aPTT were not different between wild type and mutated FXas indicating that both mutations have little impact on the activity of edoxaban. In conclusion, these data suggest that edoxaban has little interpatient variability stemming from SNPs in the factor X gene.

  16. Factors modifying the frequency of spontaneous activity in gastric muscle.

    PubMed

    Suzuki, H; Kito, Y; Hashitani, H; Nakamura, E

    2006-11-01

    The cellular mechanisms that determine the frequency of spontaneous activity were investigated in gastric smooth muscles isolated from the guinea-pig. Intact antral muscle generated slow waves periodically; the interval between slow waves was decreased exponentially by depolarization of the membrane to reach a steady interval value of about 7 s. Isolated circular muscle bundles produced slow potentials spontaneously or were evoked by depolarizing current stimuli. Evoked slow potentials appeared in an all-or-none fashion, with a refractory period of approximately 2-3 s. Low concentrations of chemicals that modify intracellular signalling revealed that the refractory period was causally related to the activity of protein kinase C (PKC). Activation of PKC increased and inhibition of PKC activity decreased the frequency of slow potentials. Chemicals that inhibit mitochondrial functions reduced the frequency of slow waves. Inhibition of internal Ca(2+)-store activity decreased the amplitude, but not the frequency of slow potentials, suggesting that the amplitude is causally related to Ca(2+) release from the internal store. The results suggest that changes in [Ca(2+)](i) caused by the activity of mitochondria may play a key role in determining the frequency of spontaneous activity in gastric pacemaker cells.

  17. FACTORS AFFECTING TIME-ACTIVITY BUDGETS OF BUFFLEHEAD WINTERING IN NARRAGANSETT, BAY, RI

    EPA Science Inventory

    Daily activities of wintering waterfowl can be influenced by the physical environment and by habitat factors such as prey abundance and availability. We examined variability in diurnal activity budgets of Bufflehead (Bucephala albeola) wintering at seven locations within Narragan...

  18. Tumor necrosis factor alpha-mediated inhibition of melanogenesis is dependent on nuclear factor kappa B activation.

    PubMed

    Englaro, W; Bahadoran, P; Bertolotto, C; Buscà, R; Dérijard, B; Livolsi, A; Peyron, J F; Ortonne, J P; Ballotti, R

    1999-02-25

    Melanogenesis is a physiological process resulting in the synthesis of melanin pigments which play a crucial protective role against skin photocarcinogenesis. In vivo, solar ultraviolet light triggers the secretion of numerous keratinocyte-derived factors that are implicated in the regulation of melanogenesis. Among these, tumor necrosis factor alpha (TNFalpha), a cytokine implicated in the pro-inflammatory response, down-regulates pigment synthesis in vitro. In this report, we aimed to determine the molecular mechanisms by which this cytokine inhibits melanogenesis in B16 melanoma cells. First, we show that TNFalpha inhibits the activity and protein expression of tyrosinase which is the key enzyme of melanogenesis. Further, we demonstrate that this effect is subsequent to a down-regulation of the tyrosinase promoter activity in both basal and cAMP-induced melanogenesis. Finally, we present evidence indicating that the inhibitory effect of TNFalpha on melanogenesis is dependent on nuclear factor kappa B (NFkappaB) activation. Indeed, overexpression of this transcription factor in B16 cells is sufficient to inhibit tyrosinase promoter activity. Furthermore, a mutant of inhibitory kappa B (IkappaB), that prevents NFkappaB activation, is able to revert the effect of TNFalpha on the tyrosinase promoter activity. Taken together, our results clarify the mechanisms by which TNFalpha inhibits pigmentation and point out the key role of NFkappaB in the regulation of melanogenesis.

  19. Situational and Personality Factors: Interactive Effects on Attitude - Active Consistency

    ERIC Educational Resources Information Center

    Albrecht, Stan L.; Warner, Lyle G.

    1975-01-01

    An examination of the combined effect of a situational factor, disclosure, and two personality variables, "need for approval" and "inner-other directedness" on attitude - action relationships with respect to marijuana related attitudes and behavior of college students. Subjects with different personality characteristics were found to respond…

  20. Factors Affecting Teachers' Participation in Professional Development Activities in Turkey

    ERIC Educational Resources Information Center

    Bayar, Adem

    2013-01-01

    The purpose of this study was to examine the relationship between factors (internal [personal] and external [environmental]) and teachers' participation in professional development (PD) programs in Turkey. The researcher employed a survey design, using a multiple-stage sampling method, selecting 30 out of 66 elementary schools in the Center…

  1. The Role of Platelet-Activating Factor in Chronic Inflammation, Immune Activation, and Comorbidities Associated with HIV Infection

    PubMed Central

    Kelesidis, Theodoros; Papakonstantinou, Vasiliki; Detopoulou, Paraskevi; Fragopoulou, Elizabeth; Chini, Maria; Lazanas, Marios C.; Antonopoulou, Smaragdi

    2016-01-01

    With the advent of highly effective antiretroviral therapy, cardiovascular disease has become an important cause of morbidity and mortality among people with treated HIV-1, but the pathogenesis is unclear. Platelet-activating factor is a potent lipid mediator of inflammation that has immunomodulatory effects and a pivotal role in the pathogenesis of inflammatory disorders and cardiovascular disease. Limited scientific evidence suggests that the platelet-activating factor pathway may be a mechanistic link between HIV-1 infection, systemic inflammation, and immune activation that contribute to pathogenesis of chronic HIV-related comorbidities, including cardiovascular disease and HIV-associated neurocognitive disorders. In this review, we examine the mechanisms by which the cross-talk between HIV-1, immune dysregulation, inflammation, and perturbations in the platelet-activating factor pathway may directly affect HIV-1 immunopathogenesis. Understanding the role of platelet-activating factor in HIV-1 infection may pave the way for further studies to explore therapeutic interventions, such as diet, that can modify platelet-activating factor activity and use of platelet-activating factor inhibitors that might improve the prognosis of HIV-1 infected patients. PMID:26616844

  2. In vitro squelching of activated transcription by serum response factor: evidence for a common coactivator used by multiple transcriptional activators.

    PubMed Central

    Prywes, R; Zhu, H

    1992-01-01

    Low amounts of serum response factor (SRF) activate transcription in vitro from a fos promoter construct containing an SRF binding site. Using this human HeLa cell-derived in vitro transcription system, we have found that high amounts of SRF inhibited, or 'squelched', transcription from this construct. Transcription from several other promoters activated by different gene-specific factors, including CREB and the acidic activator VP16, was also inhibited by high amounts of SRF. Basal transcription, from TATA-only promoters, however, was not inhibited. These results suggest that SRF binds to a common factor(s) (termed coactivator) required for activated transcription by a diverse group of transcriptional activators. Inhibition of transcription by SRF could be blocked by a double stranded oligonucleotide containing an SRF binding site. Mutations in SRF which abolished its DNA binding activity also reduced its ability to inhibit transcription. In addition, a C-terminal truncation of SRF which reduced its ability to activate transcription also reduced SRF's ability to inhibit transcription. These results suggest that activation and inhibition of transcription may be mediated by SRF binding to the same factor and that SRF can only bind to this factor when SRF is bound to plasmid DNA. Images PMID:1531519

  3. ANALYSIS OF DISCRIMINATING FACTORS IN HUMAN ACTIVITIES THAT AFFECT EXPOSURE

    EPA Science Inventory

    Accurately modeling exposure to particulate matter (PM) and other pollutants ultimately involves the utilization of human location-activity databases to assist in understanding the potential variability of microenvironmental exposures. This paper critically considers and stati...

  4. Factors affecting antibacterial activity of hop compounds and their derivatives.

    PubMed

    Simpson, W J; Smith, A R

    1992-04-01

    The antibacterial effect of weak acids derived from the hop plant (Humulus lupulus L.) increased with decreasing pH. Analysis of the minimum inhibitory concentration of such compounds against Lactobacillus brevis IFO 3960 over pH 4-7 suggests that undissociated molecules were mainly responsible for inhibition of bacterial growth. The antibacterial activity of trans-isohumulone was ca 20 times greater than that of humulone, 11 times greater than that of colupulone and nine times greater than that of trans-humulinic acid when the degree of ionization was taken into account. Monovalent cations (K+, Na+, NH4+, Rb+, Li+) stimulated antibacterial activity of trans-isohumulone but the effect was smaller than that observed with H+. The response to divalent cations varied: Ca2+ had little effect on antibacterial activity, whereas Mg2+ reduced activity. Lipid materials and beta-cyclodextrin also antagonized the antibacterial action of trans-isohumulone.

  5. Regulation of factor XIa activity by platelets and alpha 1-protease inhibitor.

    PubMed Central

    Walsh, P N; Sinha, D; Kueppers, F; Seaman, F S; Blankstein, K B

    1987-01-01

    We have studied the complex interrelationships between platelets, Factor XIa, alpha 1-protease inhibitor and Factor IX activation. Platelets were shown to secrete an inhibitor of Factor XIa, and to protect Factor XIa from inactivation in the presence of alpha 1-protease inhibitor and the secreted platelet inhibitor. This protection of Factor XIa did not arise from the binding of Factor XIa to platelets, the presence of high molecular weight kininogen, or the inactivation of alpha 1-protease inhibitor by platelets. The formation of a complex between alpha 1-protease inhibitor and the active-site-containing light chain of Factor XIa was inhibited by activated platelets and by platelet releasates, but not by high molecular weight kininogen. These results support the hypothesis that platelets can regulate Factor XIa-catalyzed Factor IX activation by secreting an inhibitor of Factor XIa that may act primarily outside the platelet microenvironment and by protecting Factor XIa from inhibition, thereby localizing Factor IX activation to the platelet plug. Images PMID:3500185

  6. Mechanism of activation of elongation factor Tu by ribosome: catalytic histidine activates GTP by protonation.

    PubMed

    Aleksandrov, Alexey; Field, Martin

    2013-09-01

    Elongation factor Tu (EF-Tu) is central to prokaryotic protein synthesis as it has the role of delivering amino-acylated tRNAs to the ribosome. Release of EF-Tu, after correct binding of the EF-Tu:aa-tRNA complex to the ribosome, is initiated by GTP hydrolysis. This reaction, whose mechanism is uncertain, is catalyzed by EF-Tu, but requires activation by the ribosome. There have been a number of mechanistic proposals, including those spurred by a recent X-ray crystallographic analysis of a ribosome:EF-Tu:aa-tRNA:GTP-analog complex. In this work, we have investigated these and alternative hypotheses, using high-level quantum chemical/molecular mechanical simulations for the wild-type protein and its His85Gln mutant. For both proteins, we find previously unsuggested mechanisms as being preferred, in which residue 85, either His or Gln, directly assists in the reaction. Analysis shows that the RNA has a minor catalytic effect in the wild-type reaction, but plays a significant role in the mutant by greatly stabilizing the reaction's transition state. Given the similarity between EF-Tu and other members of the translational G-protein family, it is likely that these mechanisms of ribosome-activated GTP hydrolysis are pertinent to all of these proteins.

  7. Differential procoagulant activity of microparticles derived from monocytes, granulocytes, platelets and endothelial cells: impact of active tissue factor.

    PubMed

    Shustova, Olga N; Antonova, Olga A; Golubeva, Nina V; Khaspekova, Svetlana G; Yakushkin, Vladimir V; Aksuk, Svetlana A; Alchinova, Irina B; Karganov, Mikhail Y; Mazurov, Alexey V

    2016-12-06

    Microparticles released by activated/apoptotic cells exhibit coagulation activity as they express phosphatidylserine and some of them - tissue factor. We compared procoagulant properties of microparticles from monocytes, granulocytes, platelets and endothelial cells and assessed the impact of tissue factor in observed differences. Microparticles were sedimented (20 000g, 30 min) from the supernatants of activated monocytes, monocytic THP-1 cells, granulocytes, platelets and endothelial cells. Coagulation activity of microparticles was examined using plasma recalcification assay. The size of microparticles was evaluated by dynamic light scattering. Tissue factor activity was measured by its ability to activate factor X. All microparticles significantly accelerated plasma coagulation with the shortest lag times for microparticles derived from monocytes, intermediate - for microparticles from THP-1 cells and endothelial cells, and the longest - for microparticles from granulocytes and platelets. Average diameters of microparticles ranged within 400-600 nm. The largest microparticles were produced by endothelial cells and granulocytes, smaller - by monocytes, and the smallest - by THP-1 cells and platelets. The highest tissue factor activity was detected in microparticles from monocytes, lower activity - in microparticles from endothelial cells and THP-1 cells, and no activity - in microparticles from platelets and granulocytes. Anti-tissue factor antibodies extended coagulation lag times for microparticles from monocytes, endothelial cells and THP-1 cells and equalized them with those for microparticles from platelets and granulocytes. Higher coagulation activity of microparticles from monocytes, THP-1 cells and endothelial cells in comparison with microparticles from platelets and granulocytes is determined mainly by the presence of active tissue factor.

  8. Structure activity relationship of phenolic diterpenes from Salvia officinalis as activators of the nuclear factor E2-related factor 2 pathway.

    PubMed

    Fischedick, Justin T; Standiford, Miranda; Johnson, Delinda A; Johnson, Jeffrey A

    2013-05-01

    Nuclear factor E2-related factor 2 (Nrf2) is a transcription factor known to activate cytoprotective genes which may be useful in the treatment of neurodegenerative disease. In order to better understand the structure activity relationship of phenolic diterpenes from Salvia officinalis L., we isolated carnosic acid, carnosol, epirosmanol, rosmanol, 12-methoxy-carnosic acid, sageone, and carnosaldehyde using polyamide column, centrifugal partition chromatography, and semi-preparative high performance liquid chromatography. Isolated compounds were screened in vitro for their ability to active the Nrf2 and general cellular toxicity using mouse primary cortical cultures. All compounds except 12-methoxy-carnosic acid were able to activate the antioxidant response element. Furthermore both carnosol and carnoasldehyde were able to induce Nrf2-dependent gene expression as well as protect mouse primary cortical neuronal cultures from H(2)O(2) induced cell death.

  9. Caffeic acid phenethyl ester inhibits T-cell activation by targeting both nuclear factor of activated T-cells and NF-kappaB transcription factors.

    PubMed

    Márquez, Nieves; Sancho, Rocío; Macho, Antonio; Calzado, Marco A; Fiebich, Bernd L; Muñoz, Eduardo

    2004-03-01

    Caffeic acid phenethyl ester (CAPE), which is derived from the propolis of honeybee hives, has been shown to reveal anti-inflammatory properties. Since T-cells play a key role in the onset of several inflammatory diseases, we have evaluated the immunosuppressive activity of CAPE in human T-cells, discovering that this phenolic compound is a potent inhibitor of early and late events in T-cell receptor-mediated T-cell activation. Moreover, we found that CAPE specifically inhibited both interleukin (IL)-2 gene transcription and IL-2 synthesis in stimulated T-cells. To further characterize the inhibitory mechanisms of CAPE at the transcriptional level, we examined the DNA binding and transcriptional activities of nuclear factor (NF)-kappaB, nuclear factor of activated cells (NFAT), and activator protein-1 (AP-1) transcription factors in Jurkat cells. We found that CAPE inhibited NF-kappaB-dependent transcriptional activity without affecting the degradation of the cytoplasmic NF-kappaB inhibitory protein, IkappaBalpha. However, both NF-kappaB binding to DNA and transcriptional activity of a Gal4-p65 hybrid protein were clearly prevented in CAPE-treated Jurkat cells. Moreover, CAPE inhibited both the DNA-binding and transcriptional activity of NFAT, a result that correlated with its ability to inhibit phorbol 12-myristate 13-acetate plus ionomycin-induced NFAT1 dephosphorylation. These findings provide new insights into the molecular mechanisms involved in the immunomodulatory and anti-inflammatory activities of this natural compound.

  10. Misfolded proteins activate Factor XII in humans, leading to kallikrein formation without initiating coagulation

    PubMed Central

    Maas, Coen; Govers-Riemslag, José W.P.; Bouma, Barend; Schiks, Bettina; Hazenberg, Bouke P.C.; Lokhorst, Henk M.; Hammarström, Per; ten Cate, Hugo; de Groot, Philip G.; Bouma, Bonno N.; Gebbink, Martijn F.B.G.

    2008-01-01

    When blood is exposed to negatively charged surface materials such as glass, an enzymatic cascade known as the contact system becomes activated. This cascade is initiated by autoactivation of Factor XII and leads to both coagulation (via Factor XI) and an inflammatory response (via the kallikrein-kinin system). However, while Factor XII is important for coagulation in vitro, it is not important for physiological hemostasis, so the physiological role of the contact system remains elusive. Using patient blood samples and isolated proteins, we identified a novel class of Factor XII activators. Factor XII was activated by misfolded protein aggregates that formed by denaturation or by surface adsorption, which specifically led to the activation of the kallikrein-kinin system without inducing coagulation. Consistent with this, we found that Factor XII, but not Factor XI, was activated and kallikrein was formed in blood from patients with systemic amyloidosis, a disease marked by the accumulation and deposition of misfolded plasma proteins. These results show that the kallikrein-kinin system can be activated by Factor XII, in a process separate from the coagulation cascade, and point to a protective role for Factor XII following activation by misfolded protein aggregates. PMID:18725990

  11. A transcription factor active on the epidermal growth factor receptor gene.

    PubMed Central

    Kageyama, R; Merlino, G T; Pastan, I

    1988-01-01

    We have developed an in vitro transcription system for the epidermal growth factor receptor (EGFR) oncogene by using nuclear extracts of A431 human epidermoid carcinoma cells, which overproduce EGFR. We found that a nuclear factor, termed EGFR-specific transcription factor (ETF), specifically stimulated EGFR transcription by 5- to 10-fold. In this report, ETF, purified by using sequence-specific oligonucleotide affinity chromatography, is shown by renaturing material eluted from a NaDodSO4/polyacrylamide gel to be a protein with a molecular mass of 120 kDa. ETF binds to the promoter region, as measured by DNase I "footprinting" and gel-mobility-shift assays, and specifically stimulates the transcription of the EGFR gene in a reconstituted in vitro transcription system. These results suggest that ETF could play a role in the overexpression of the cellular oncogene EGFR. Images PMID:3393529

  12. Factors Related to Exclusion of Students from School Activities.

    ERIC Educational Resources Information Center

    Weber, Larry J.; And Others

    A survey of 130 high school principals in 3 southern states revealed alcohol abuse, insubordination, and other misbehavior as the major causes for excluding students from participation in school activities. The study also indicated that students have to meet disproportionately higher standards to participate in athletics, cheerleading, and student…

  13. Factors Influencing Physical Activity among Postpartum Iranian Women

    ERIC Educational Resources Information Center

    Roozbahani, Nasrin; Ghofranipour, Fazlollah; Eftekhar Ardabili, Hassan; Hajizadeh, Ebrahim

    2014-01-01

    Background: Postpartum women are a population at risk for sedentary living. Physical activity (PA) prior to pregnancy may be effective in predicting similar behaviour in the postpartum period. Objective: To test a composite version of the extended transtheoretical model (TTM) by adding "past behaviour" in order to predict PA behaviour…

  14. Annexin A2 Enhances Complement Activation by Inhibiting Factor H1

    PubMed Central

    Renner, Brandon; Tong, Hua Hua; Laskowski, Jennifer; Jonscher, Karen; Goetz, Lindsey; Woolaver, Rachel; Hannan, Jonathan; Li, Yong Xing; Hourcade, Dennis; Pickering, Matthew C.; Holers, V. Michael; Thurman, Joshua M.

    2015-01-01

    Factor H is a circulating protein that regulates activation of the alternative pathway (AP) of complement. Mutations and genetic variations of factor H are associated with several AP-mediated diseases, highlighting the critical role of factor H in AP regulation. AP-mediated inflammation is typically triggered by illness or tissue injury, however, and tissue injury can trigger AP activation in individuals with fully functional factor H. This suggests that factor H function is affected by local conditions within tissues. We hypothesized that inducible proteins impair the ability of factor H to locally control the AP, thereby increasing AP activation. We used purified murine factor H to immunoprecipitate binding partners from mouse kidneys. Using immunoaffinity liquid chromatography-mass spectrometry we then identified annexin A2 as a factor H binding partner. Further experiments showed that annexin A2 reduces the binding of factor H to cell surfaces. Recombinant annexin A2 impaired complement regulation by factor H, and increased complement activation on renal cell surfaces in vitro and in vivo. In a murine model of acute pneumococcal otitis media the administration of annexin A2 increased AP-mediated bacterial opsonization and clearance. In conclusion, the local production of annexin A2 within tissues suppresses regulation of the AP by factor H. Annexin A2 can contribute to AP-mediated tissue inflammation by locally impairing factor H function, but annexin A2 can also improve complement-mediated bacterial clearance. PMID:26729803

  15. Nuclear factor E2-related factor-2 (Nrf2) is required for NLRP3 and AIM2 inflammasome activation.

    PubMed

    Zhao, Changcheng; Gillette, Devyn D; Li, Xinghui; Zhang, Zhibin; Wen, Haitao

    2014-06-13

    Despite the number of extensive studies on the immune function and signaling of inflammasomes in various diseases, the activating mechanism of inflammasome, especially the NLRP3 inflammasome, is not fully understood. Nuclear factor E2-related Factor-2 (Nrf2), a key transcription factor that regulates cellular redox homeostasis, has been reported to play both protective and pathogenic roles depending on the disease conditions through undefined mechanism. This study reveals an essential role of Nrf2 in inflammasome activation. LPS stimulation increased Nrf2 protein levels in a Myd88-dependent manner. When compared with wild-type controls, Nrf2-deficient (Nrf2(-/-)) macrophages showed decreased maturation and secretion of caspase-1 and IL-1β and reduced apoptosis-associated speck-like protein containing CARD (ASC) speck formation in response to various NLRP3 and AIM2 inflammasome stimuli. In contrast, NLRC4 inflammasome activation was not controlled by Nrf2. Biochemical analysis revealed that Nrf2 appeared in the ASC-enriched cytosolic compartment after NLRP3 inflammasome activation. Furthermore, mitochondrial reactive oxygen species-induced NLRP3 activation also required Nrf2. Nrf2(-/-) mice showed a dramatic decrease in immune cell recruitment and IL-1β generation in alum-induced peritonitis, which is a typical IL-1 signaling-dependent inflammation animal model. This work discovered a critical proinflammatory effect of Nrf2 by mediating inflammasome activation.

  16. Nuclear Factor E2-related Factor-2 (Nrf2) Is Required for NLRP3 and AIM2 Inflammasome Activation*

    PubMed Central

    Zhao, Changcheng; Gillette, Devyn D.; Li, Xinghui; Zhang, Zhibin; Wen, Haitao

    2014-01-01

    Despite the number of extensive studies on the immune function and signaling of inflammasomes in various diseases, the activating mechanism of inflammasome, especially the NLRP3 inflammasome, is not fully understood. Nuclear factor E2-related Factor-2 (Nrf2), a key transcription factor that regulates cellular redox homeostasis, has been reported to play both protective and pathogenic roles depending on the disease conditions through undefined mechanism. This study reveals an essential role of Nrf2 in inflammasome activation. LPS stimulation increased Nrf2 protein levels in a Myd88-dependent manner. When compared with wild-type controls, Nrf2-deficient (Nrf2−/−) macrophages showed decreased maturation and secretion of caspase-1 and IL-1β and reduced apoptosis-associated speck-like protein containing CARD (ASC) speck formation in response to various NLRP3 and AIM2 inflammasome stimuli. In contrast, NLRC4 inflammasome activation was not controlled by Nrf2. Biochemical analysis revealed that Nrf2 appeared in the ASC-enriched cytosolic compartment after NLRP3 inflammasome activation. Furthermore, mitochondrial reactive oxygen species-induced NLRP3 activation also required Nrf2. Nrf2−/− mice showed a dramatic decrease in immune cell recruitment and IL-1β generation in alum-induced peritonitis, which is a typical IL-1 signaling-dependent inflammation animal model. This work discovered a critical proinflammatory effect of Nrf2 by mediating inflammasome activation. PMID:24798340

  17. Symbiotic activity of pea (Pisum sativum) after application of Nod factors under field conditions.

    PubMed

    Siczek, Anna; Lipiec, Jerzy; Wielbo, Jerzy; Kidaj, Dominika; Szarlip, Paweł

    2014-04-29

    Growth and symbiotic activity of legumes are mediated by Nod factors (LCO, lipo-chitooligosaccharides). To assess the effects of application of Nod factors on symbiotic activity and yield of pea, a two-year field experiment was conducted on a Haplic Luvisol developed from loess. Nod factors were isolated from Rhizobium leguminosarum bv. viciae strain GR09. Pea seeds were treated with the Nod factors (10⁻¹¹ M) or water (control) before planting. Symbiotic activity was evaluated by measurements of nitrogenase activity (acetylene reduction assay), nodule number and mass, and top growth by shoot mass, leaf area, and seed and protein yield. Nod factors generally improved pea yield and nitrogenase activity in the relatively dry growing season 2012, but not in the wet growing season in 2013 due to different weather conditions.

  18. Symbiotic Activity of Pea (Pisum sativum) after Application of Nod Factors under Field Conditions

    PubMed Central

    Siczek, Anna; Lipiec, Jerzy; Wielbo, Jerzy; Kidaj, Dominika; Szarlip, Paweł

    2014-01-01

    Growth and symbiotic activity of legumes are mediated by Nod factors (LCO, lipo-chitooligosaccharides). To assess the effects of application of Nod factors on symbiotic activity and yield of pea, a two-year field experiment was conducted on a Haplic Luvisol developed from loess. Nod factors were isolated from Rhizobium leguminosarum bv. viciae strain GR09. Pea seeds were treated with the Nod factors (10−11 M) or water (control) before planting. Symbiotic activity was evaluated by measurements of nitrogenase activity (acetylene reduction assay), nodule number and mass, and top growth by shoot mass, leaf area, and seed and protein yield. Nod factors generally improved pea yield and nitrogenase activity in the relatively dry growing season 2012, but not in the wet growing season in 2013 due to different weather conditions. PMID:24786094

  19. Platelet-Derived Short-Chain Polyphosphates Enhance the Inactivation of Tissue Factor Pathway Inhibitor by Activated Coagulation Factor XI

    PubMed Central

    Puy, Cristina; Tucker, Erik I.; Ivanov, Ivan S.; Gailani, David; Smith, Stephanie A.; Morrissey, James H.; Gruber, András; McCarty, Owen J. T.

    2016-01-01

    Introduction Factor (F) XI supports both normal human hemostasis and pathological thrombosis. Activated FXI (FXIa) promotes thrombin generation by enzymatic activation of FXI, FIX, FX, and FV, and inactivation of alpha tissue factor pathway inhibitor (TFPIα), in vitro. Some of these reactions are now known to be enhanced by short-chain polyphosphates (SCP) derived from activated platelets. These SCPs act as a cofactor for the activation of FXI and FV by thrombin and FXIa, respectively. Since SCPs have been shown to inhibit the anticoagulant function of TFPIα, we herein investigated whether SCPs could serve as cofactors for the proteolytic inactivation of TFPIα by FXIa, further promoting the efficiency of the extrinsic pathway of coagulation to generate thrombin. Methods and Results Purified soluble SCP was prepared by size-fractionation of sodium polyphosphate. TFPIα proteolysis was analyzed by western blot. TFPIα activity was measured as inhibition of FX activation and activity in coagulation and chromogenic assays. SCPs significantly accelerated the rate of inactivation of TFPIα by FXIa in both purified systems and in recalcified plasma. Moreover, platelet-derived SCP accelerated the rate of inactivation of platelet-derived TFPIα by FXIa. TFPIα activity was not affected by SCP in recalcified FXI-depleted plasma. Conclusions Our data suggest that SCP is a cofactor for TFPIα inactivation by FXIa, thus, expanding the range of hemostatic FXIa substrates that may be affected by the cofactor functions of platelet-derived SCP. PMID:27764259

  20. Nervous factors influencing the membrane activity of intestinal smooth muscle

    PubMed Central

    Kuriyama, H.; Osa, T.; Toida, N.

    1967-01-01

    The effects of various chemical agents on the spontaneous membrane activities and those electrically elicited in the smooth muscles of small intestine were investigated. 1. The effects of various chemicals on the spontaneously active membrane might be summarized as follows. (a) Cholinergic agents; atropine slightly hyperpolarized the membrane and reduced the amplitude of slow potential changes even in aged preparations. Prostigmine depolarized the membrane, and enhanced the amplitude and prolonged the duration of the slow potential changes. Atropine prevented the actions of prostigmine on the membrane. (b) Ba2+ depolarized the membrane, and enhanced the amplitude and prolonged the duration of the slow potential changes. The spike frequency was initially increased, then reduced. Atropine and tetrodotoxin partially prevented the action of Ba2+ on the membrane activities. 2. Effects of chemical agents on the membrane activity elicited by electrical stimulation might be summarized as follows. (a) Short pulse stimulation (0·5-1 msec) generated the spike as a direct response of the muscle cell membrane, then it was followed by slow depolarization, delayed hyperpolarization, i.e. the `inhibitory potential', and post-inhibitory rebound successively. (b) The slow depolarization and the post-inhibitory rebound were reduced in amplitude by treatment with atropine, and enhanced by treatments with prostigmine and Ba2+. Tetrodotoxin blocked all activities except the spike. 3. When repetitive stimulation (20 c/s) was applied to the membrane, the membrane hyperpolarized; then, after 3-5 sec, it gradually depolarized even if the stimulation was continued, and triggered spikes. The hyperpolarization always preceded depolarization. The duration and the amplitude of the delayed depolarization was proportionally increased by the increased intensity and duration of stimulation. Atropine and tetrodotoxin blocked the generation of the post-inhibitory rebound. 4. Effects of repetitive

  1. Factors affecting the adsorption of chromium (VI) on activated carbon

    SciTech Connect

    Yavuz, R.; Orbak, I.; Karatepe, N.

    2006-09-15

    The aim of this investigation was to determine the adsorption behavior of chromium (VI) on two different activated carbon samples produced from Tuncbilek lignite. The effects of the initial chromium (VI) concentration (250-1000 mg/L), temperature (297-323 K) and pH (2.0-9.5) on adsorption were investigated systematically. The effectiveness of the parameters on chromium adsorption was found to be in the order of pH, the initial Cr(VI) concentration and the temperature. Increasing the pH from 2.0 to 9.5 caused a decrease in adsorption. However, the adsorption was increased by increasing the initial Cr(VI) concentration and temperature. The multilinear mathematical model was also developed to predict the Cr(VI) adsorption on activated carbon samples within the experimental conditions.

  2. Expression and Activation of STAT Transcription Factors in Breast Cancer

    DTIC Science & Technology

    1998-05-08

    several other studies suggest that estrogen given in low doses to relieve menopausal symptoms probably does not increase the incidence of breast cancer...breast cancer. ’It was recently demonstrated that, while .overall STAT DNA-bindinq activity is low in normal breast and benign lesions, it is...adjuvant anticancer treatment, particularly in chronic myelogenous leukemia, maliqnant melanoma, low · grade lymphoma, multiple myeloma, and midgut

  3. Factors affecting the adsorption of xenon on activated carbon

    SciTech Connect

    Underhill, D.W.; DiCello, D.C.; Scaglia, L.A.; Watson, J.A.

    1986-08-01

    The presence of water vapor was found to interfere strongly with the dynamic adsorption of /sup 133/Xe on coconut-base activated charcoal. The percent loss in the xenon adsorption coefficient was similar to values reported earlier for the adsorption of krypton on humidified charcoal. Attempts to increase the adsorption of xenon by (a) using a petroleum-based adsorbent with an extremely high surface area and (b) by impregnation of the adsorbent with iodine were not successful.

  4. Salivary Platelet Activating Factor Levels in Periodontal Disease

    DTIC Science & Technology

    1991-05-01

    multifarious and is activated through multiple mediators. The inflammatory process can be subdivided into acute and chronic inflammation. Stedman’s Medical...Just recently, inflammed human gingival tissues were analyzed and found to contain PAF (Noguchi, et al, 1989). Thus, multiple components of the...17.9% release of peroxidase, 20.6% release of P-glucuronidase, 22.4% release of alkaline phosphatase and 28.8% release of aryl sulfatase . At higher

  5. Factors influencing cellulosome activity in consolidated bioprocessing of cellulosic ethanol.

    PubMed

    Xu, Chenggang; Qin, Yong; Li, Yudong; Ji, Yuetong; Huang, Jianzhong; Song, Houhui; Xu, Jian

    2010-12-01

    The cellulosome, a multi-subunit protein complex catalyzing cellulose degradation in cellulolytic Clostridium thermocellum, plays a crucial role in Consolidated Bioprocessing (CBP) of lignocellulose into ethanol. Here, activity of cellulosome was tested under varying concentrations of chemical compounds derived from lignocellulose pretreatment and fermentation. We found that, firstly, the cellulolytic activity of cellulosome was actually promoted by formate, acetate and lactate; secondly, cellulosome was tolerant up to 5mM furfural, 50mM p-hydroxybenzoic acid and 1mM catechol. Furthermore, the cellulosome exhibited higher ethanol tolerance and thermostability than commercialized fungal (Trichoderma reesei) cellulase. To probe the implication of these unique enzyme-features, C. thermocellum JYT01 was cultured under conditions optimal for cellulosome activity. This CBP system yielded 491 mM ethanol, the highest level reported thus far for C. thermocellum monocultures. These findings demonstrate the potential advantages of bacterial cellulosome, and provide a novel strategy for design, selection and optimization of the cellulosome-ethanologen partnership.

  6. Platelet factor 4 stimulates thrombomodulin protein C-activating cofactor activity. A structure-function analysis.

    PubMed

    Slungaard, A; Key, N S

    1994-10-14

    Thrombomodulin (TM) is an anionic (pI approximately 4) protein cofactor that promotes thrombin (THR) cleavage of protein C to generate activated protein C (APC), a potent anticoagulant. We find that the cationic platelet alpha-granule protein platelet factor 4 (PF4) stimulates 4-25-fold the cofactor activity of rabbit TM and two differentially glycanated versions of an extracellular domain human TM polypeptide in which the glycosaminoglycan (GAG) is either present (GAG+ TM) or absent (GAG- TM) with an ED50 of 3.3-10 micrograms/ml. No such stimulation occurs in response to beta-thromboglobulin or thrombospondin, or when protein C lacking its gamma-carboxyglutamic acid (Gla) domain is the substrate. Heparin and chondroitin sulfates A and E reverse PF4 stimulation. PF4 minimally affects the Kd for THR but decreases 30-fold (from 8.3 to 0.3 microM) the Km for protein C of APC generation by GAG+ TM. PF4 also strikingly transforms the [Ca2+] dependence profile of rabbit and GAG+ TM to resemble that of GAG- TM. A potential explanation for this is that PF4, like Ca2+, induces heparin-reversible alterations in native (but not Gla-domainless) protein C conformation as assessed by autofluorescence emission analysis. We conclude that PF4 stimulates TM APC generation by interacting electrostatically with both the TM GAG and the protein C Gla domain to enhance markedly the affinity of the THR.TM complex for protein C. By this mechanism, PF4 may play a previously unsuspected role in the physiologic regulation of clotting.

  7. Differential roles of tissue factor and phosphatidylserine in activation of coagulation.

    PubMed

    Spronk, Henri M H; ten Cate, Hugo; van der Meijden, Paola E J

    2014-05-01

    It has been suggested that the main physiological trigger of coagulation, tissue factor, possesses limited procoagulant activity and occurs in an inactive or so-called encrypted state. For the conversion of encrypted into decrypted tissue factor with sufficient procoagulant activity, four distinct models have been proposed: 1; dimer formation, 2; lipid rafts, 3; disulfide bonds, and 4; phosphatidylserine exposure. Pro and cons can be given for each of these mechanisms of tissue factor encryption/decryption, however, it seems most likely that two or more mechanisms act together in activating the procoagulant activity. The exposure of phosphatidylserine in the outer layer of cell membranes supports coagulation through enhanced formation of the tenase (factors IXa, VIIIa and X) and prothrombinase (factors Xa, Va and prothrombin) complexes. The proposed role for phosphatidylserine in decryption of tissue factor could contribute to the correct orientation of the tissue factor - factor VII complex. Overall, the contribution of both tissue factor and phosphatidylserine to coagulation seems distinct with tissue factor being the physiological activator and phosphatidylserine the driving force of propagation of coagulation.

  8. Interaction of Leptospira elongation factor Tu with plasminogen and complement factor H: a metabolic leptospiral protein with moonlighting activities.

    PubMed

    Wolff, Danielly G; Castiblanco-Valencia, Mónica M; Abe, Cecília M; Monaris, Denize; Morais, Zenaide M; Souza, Gisele O; Vasconcellos, Sílvio A; Isaac, Lourdes; Abreu, Patrícia A E; Barbosa, Angela S

    2013-01-01

    The elongation factor Tu (EF-Tu), an abundant bacterial protein involved in protein synthesis, has been shown to display moonlighting activities. Known to perform more than one function at different times or in different places, it is found in several subcellular locations in a single organism, and may serve as a virulence factor in a range of important human pathogens. Here we demonstrate that Leptospira EF-Tu is surface-exposed and performs additional roles as a cell-surface receptor for host plasma proteins. It binds plasminogen in a dose-dependent manner, and lysine residues are critical for this interaction. Bound plasminogen is converted to active plasmin, which, in turn, is able to cleave the natural substrates C3b and fibrinogen. Leptospira EF-Tu also acquires the complement regulator Factor H (FH). FH bound to immobilized EF-Tu displays cofactor activity, mediating C3b degradation by Factor I (FI). In this manner, EF-Tu may contribute to leptospiral tissue invasion and complement inactivation. To our knowledge, this is the first description of a leptospiral protein exhibiting moonlighting activities.

  9. Activation of factor XII-dependent pathways in human plasma by hematin and protoporphyrin.

    PubMed Central

    Becker, C G; Wagner, M; Kaplan, A P; Silverberg, M; Grady, R W; Liem, H; Muller-Eberhard, U

    1985-01-01

    Intravenous administration of hematin is effective in the treatment of acute exacerbations of the inducible porphyrias. In the course of such treatment, coagulopathies have occurred that are characterized by prolongation of prothrombin time, partial thromboplastin time, and formation of fibrin split products. In experiments in vitro with normal human plasma, we observed that hematin and protoporphyrin activated Factor XII-dependent pathways of coagulation and fibrinolysis, and that they generated kallikrein activity. Incubation of protoporphyrin with purified Factor XII resulted in activation as measured by amidolysis of a chromogenic substrate. Neither coproporphyrin, uroporphyrin, delta-aminolevulinic acid, porphobilinogen, or bilirubin activated Factor XII-dependent pathways. Exposure of serum containing added uroporphyrin, coproporphyrin, and protoporphyrin, but not hematin, to ultraviolet light (405 nm) resulted in activation of the classical pathway of the complement system. On the other hand, exposure of plasma containing uroporphyrin or coproporphyrin to ultraviolet light did not result in activation of Factor XII-dependent pathways. PMID:4031058

  10. [Family factors influence active commuting to school in Spanish children].

    PubMed

    Rodríguez-López, Carlos; Villa-González, Emilio; Pérez-López, Isaac J; Delgado-Fernández, Manuel; Ruiz, Jonatan R; Chillón, Palma

    2013-01-01

    Introducción: El desplazamiento activo al colegio contribuye a aumentar los niveles de actividad física en niños. Los factores familiares pueden determinar dicho comportamiento. Objetivo: El objetivo fue analizar la asociación de la actividad laboral y el desplazamiento al trabajo de los padres con el modo de desplazamiento de sus hijos. Método: Participaron 721 familias de 4 colegios de la provincia de Granada. Las familias completaron un cuestionario sobre el modo de desplazamiento de sus hijos, la actividad laboral y el modo de desplazamiento de los padres, y la distancia y tiempo del trayecto al colegio de sus hijos. Las asociaciones entre la actividad laboral de las familias y modo de desplazamiento al trabajo con el desplazamiento activo al colegio de sus hijos se estudiaron con regresión logística binaria ajustando por distancia al colegio y edad de los hijos. Resultados: Los niños cuyos padres y madres no trabajaban eran más propensos a ir de forma activa al colegio que aquellos donde ambos trabajaban (p = 0,023; OR: 2,67; 95% IC: 1,14-6,23). Los niños cuyos padres y madres se desplazaban de forma activa al trabajo eran más propensos a ir de forma activa al colegio que aquellos donde ambos padres se desplazaban de forma pasiva al trabajo (p = 0,014; OR: 6,30; 95% IC: 1,45-27,26). Conclusión: Los factores familiares estaban relacionados con el modo de desplazamiento de los niños al colegio: en familias con desempleo y en familias con empleo donde los padres se desplazan al trabajo de forma activa, los hijos parecen ser más activos.

  11. An essential role for platelet-activating factor in activating mast cell migration following ultraviolet irradiation

    PubMed Central

    Chacón-Salinas, Rommel; Chen, Limo; Chávez-Blanco, Alma D.; Limón-Flores, Alberto Y.; Ma, Ying; Ullrich, Stephen E.

    2014-01-01

    The UVB (290–320 nm) radiation in sunlight is responsible for inducing skin cancer. Exposure to UV radiation is also immunosuppressive, and the systemic immune suppression induced by UV is a well-recognized risk factor for cancer induction. As UVB radiation is absorbed within the upper layers of the skin, indirect mechanisms must play a role in activating systemic immune suppression. One prominent example is mast cell migration, which from the skin to the draining LN is an essential step in the cascade of events leading to immune suppression. What triggers mast cell migration is not entirely clear. Here, we tested the hypothesis that PAF, a lipid mediator of inflammation produced by the skin in response to UV exposure, is involved. Mast cell-deficient mice (KitW-sh/W-sh) are resistant to the suppressive effect of UV radiation, and reconstituting mast cell-deficient mice with normal bone marrow-derived mast cells restores susceptibility to immunosuppression. However, when mast cells from PAFR−/− mice were used, the reconstituted mice were not susceptible to the suppressive effects of UV. Furthermore, PAFR−/− mice showed impaired UV-induced mast cell migration when compared with WT mice. Finally, injecting PAF into WT mice mimicked the effect of UV irradiation and induced mast cell migration but not in PAFR−/− mice. Our findings indicate that PAFR binding induces mast cells to migrate from the skin to the LNs, where they mediate immune suppression. PMID:24009177

  12. Platelet-aggregating activity of released factor(s) from Trypanosoma brucei brucei.

    PubMed

    Nwagwu, M; Inyang, A L; Molokwu, R I; Essien, E M

    1989-12-01

    The effect of factors derived from Trypanosoma brucei brucei on rat platelets was studied. T. brucei at a concentration of 4 X 10(9) trypanosomes/ml phosphate saline glucose (PSG) was stored at -20 degrees C for 18 h, thawed, and a supernatant fraction, trypanosome-derived supernatant (TDS) was obtained by spinning the sample at 3000 g for 10 min at 20 degrees C. Normal rat platelets, prepared as platelet-rich plasma (PRP), were then incubated with TDS in the absence or presence of ADP (0.05-0.1 microM). The results showed that approximately 83% platelet aggregation was induced by addition of TDS (50 microliters; 113 micrograms protein) to 100 microliters PRP with a platelet count of 10(6). simultaneous addition of ADP and TDS to PRP produced a synergistic effect. It was also shown that a supernatant fraction, obtained by incubating live T. brucei (4 X 10(9)/microliters PSG) at 0 degrees C 1 h and spinning down the trypanosomes (3000 g for 10 min), also induced platelet aggregation. The nature of the factor(s) derived from, or released by, T. brucei inducing platelet aggregation is being investigated but it has been shown not to be ADP.

  13. Factor Activity Assays for Monitoring Extended Half-Life FVIII and Factor IX Replacement Therapies.

    PubMed

    Kitchen, Steve; Tiefenbacher, Stefan; Gosselin, Robert

    2017-04-01

    The advent of modified factor VIII (FVIII) and factor IX (FIX) molecules with extended half-lives (EHLs) compared with native FVIII and FIX represents a major advance in the field of hemophilia care, with the potential to reduce the frequency of prophylactic injections and/or to increase the trough level prior to subsequent injections. Monitoring treatment through laboratory assays will be an important part of ensuring patient safety, including any tailoring of prophylaxis. Several approaches have been used to extend half-lives, including PEGylation, and fusion to albumin or immunoglobulin. Some of these modifications affect factor assays as routinely performed in hemophilia centers; so, laboratories will need to use FVIII and FIX assays which have been shown to be suitable on a product-by-product basis. For some products, there are marked differences between results obtained using one-stage or chromogenic assays and results obtained using different reagents in the one-stage assay. The laboratory should use an assay in which the recovery of the product closely aligns with the assay used by the pharmaceutical company to assign potency to the product, so that the units reported by the laboratory agree with those used to demonstrate efficacy of the product during clinical trials. Reported assay differences in relation to several of the EHL FVIII and FIX molecules will be reviewed in this article.

  14. Growth Factor Midkine Promotes T-Cell Activation through Nuclear Factor of Activated T Cells Signaling and Th1 Cell Differentiation in Lupus Nephritis.

    PubMed

    Masuda, Tomohiro; Maeda, Kayaho; Sato, Waichi; Kosugi, Tomoki; Sato, Yuka; Kojima, Hiroshi; Kato, Noritoshi; Ishimoto, Takuji; Tsuboi, Naotake; Uchimura, Kenji; Yuzawa, Yukio; Maruyama, Shoichi; Kadomatsu, Kenji

    2017-04-01

    Activated T cells play crucial roles in the pathogenesis of autoimmune diseases, including lupus nephritis (LN). The activation of calcineurin/nuclear factor of activated T cells (NFAT) and STAT4 signaling is essential for T cells to perform various effector functions. Here, we identified the growth factor midkine (MK; gene name, Mdk) as a novel regulator in the pathogenesis of 2,6,10,14-tetramethylpentadecane-induced LN via activation of NFAT and IL-12/STAT4 signaling. Wild-type (Mdk(+/+)) mice showed more severe glomerular injury than MK-deficient (Mdk(-/-)) mice, as demonstrated by mesangial hypercellularity and matrix expansion, and glomerular capillary loops with immune-complex deposition. Compared with Mdk(-/-) mice, the frequency of splenic CD69(+) T cells and T helper (Th) 1 cells, but not of regulatory T cells, was augmented in Mdk(+/+) mice in proportion to LN disease activity, and was accompanied by skewed cytokine production. MK expression was also enhanced in activated CD4(+) T cells in vivo and in vitro. MK induced activated CD4(+) T cells expressing CD69 through nuclear activation of NFAT transcription and selectively increased in vitro differentiation of naive CD4(+) T cells into Th1 cells by promoting IL-12/STAT4 signaling. These results suggest that MK serves an indispensable role in the NFAT-regulated activation of CD4(+) T cells and Th1 cell differentiation, eventually leading to the exacerbation of LN.

  15. Relation of physical activity to cardiovascular disease mortality and the influence of cardiometabolic risk factors.

    PubMed

    Reddigan, Jacinta I; Ardern, Chris I; Riddell, Michael C; Kuk, Jennifer L

    2011-11-15

    Physical activity can improve several metabolic risk factors associated with cardiovascular disease (CVD) and is associated with a lower risk of CVD mortality. We sought to evaluate the extent to which metabolic risk factors mediate the association between physical activity and CVD mortality and whether physical activity provides protective effects against CVD mortality in healthy adults and those with metabolic risk factors. A sample of 10,261 adults from the Third National Health and Nutrition Examination Survey with public-access mortality data linkage (follow-up 13.4 ± 3.9 years) was used. Physical activity was assessed by questionnaire and classified into inactive, light, and moderate/vigorous activity categories. Metabolic risk factors (dyslipidemia, type 2 diabetes mellitus, obesity, hypertension, inflammation, and insulin resistance) were categorized using clinical thresholds. After adjusting for basic confounders, engaging in light or moderate/vigorous physical activity was associated with a lower risk of CVD mortality (p < 0.05). Adjustment for each risk-factor set only slightly attenuated this relation. When all risk-factor sets were added to the model simultaneously, light (hazard ratio 0.72, 0.62 to 0.84) and moderate/vigorous (hazard ratio 0.72, 0.62 to 0.85) activity remained at lower risk of CVD mortality. In addition, physical activity provided protective effects for CVD mortality in healthy subjects and those with metabolic risk factors in isolation or in clusters. In conclusion, physical activity was associated with a lower risk of CVD mortality independent of traditional and inflammatory risk factors. Taken together these results suggest that physical activity may protect against CVD mortality regardless of the presence of metabolic risk factors.

  16. Real-World Affected Upper Limb Activity in Chronic Stroke: An Examination of Potential Modifying Factors

    PubMed Central

    Bailey, Ryan R.; Birkenmeier, Rebecca L.; Lang, Catherine E.

    2015-01-01

    BACKGROUND Despite improvement in motor function after intervention, adults with chronic stroke experience disability in everyday activity. Factors other than motor function may influence affected upper limb (UL) activity. OBJECTIVE To characterize affected UL activity and examine potential modifying factors of affected UL activity in community-dwelling adults with chronic stroke. METHODS Forty-six adults with chronic stroke wore accelerometers on both ULs for 25 hours and provided information about potential modifying factors (time spent in sedentary activity, cognitive impairment, depressive symptomatology, number of comorbidities, motor dysfunction of the affected UL, age, activities of daily living (ADL) status, and living arrangement). Accelerometry was used to quantify duration of affected and unaffected UL activity. The ratio of affected-to-unaffected UL activity was also calculated. Associations within and between accelerometry-derived variables and potential modifying factors were examined. RESULTS Mean hours of affected and unaffected UL activity were 5.0 ± 2.2 and 7.6 ± 2.1 hours, respectively. The ratio of affected-to-unaffected UL activity was 0.64 ± 0.19, and hours of affected and unaffected UL activity were strongly correlated (r=0.78). Increased severity of motor dysfunction and dependence in ADLs were associated with decreased affected UL activity. No other factors were associated with affected UL activity. CONCLUSIONS Severity of motor dysfunction and ADL status should be taken into consideration when setting goals for UL activity in people with chronic stroke. Given the strong, positive correlation between affected and unaffected UL activity, encouragement to increase activity of the unaffected UL may increase affected UL activity. PMID:25776118

  17. Evidence for a prevalent dimorphism in the activation peptide of human coagulation factor IX.

    PubMed Central

    McGraw, R A; Davis, L M; Noyes, C M; Lundblad, R L; Roberts, H R; Graham, J B; Stafford, D W

    1985-01-01

    We have independently isolated and characterized cDNA and genomic clones for the human coagulation factor IX. Sequence analysis in both cases indicates that threonine is encoded by the triplet ACT as the third residue of the activation peptide. This is in agreement with some earlier reports but in disagreement with others that show the alanine triplet GCT at this position. The discrepancy can thus be accounted for by natural variation of a single nucleotide in the normal population. Amino acid sequence analyses of activated factor IX from plasma samples of four individuals yielded two cases of alanine and two cases of threonine at the third position of the activation peptide. In factor IX from pooled plasma and in factor IX from a heterozygous individual, however, both alanine and threonine were found. Taken together, the findings show that a prevalent nondeleterious dimorphism exists in the activation peptide of human coagulation factor IX. PMID:3857619

  18. Prebiotic Factors Influencing the Activity of a Ligase Ribozyme.

    PubMed

    Anella, Fabrizio; Danelon, Christophe

    2017-04-06

    An RNA-lipid origin of life scenario provides a plausible route for compartmentalized replication of an informational polymer and subsequent division of the container. However, a full narrative to form such RNA protocells implies that catalytic RNA molecules, called ribozymes, can operate in the presence of self-assembled vesicles composed of prebiotically relevant constituents, such as fatty acids. Hereby, we subjected a newly engineered truncated variant of the L1 ligase ribozyme, named tL1, to various environmental conditions that may have prevailed on the early Earth with the objective to find a set of control parameters enabling both tL1-catalyzed ligation and formation of stable myristoleic acid (MA) vesicles. The separate and concurrent effects of temperature, concentrations of Mg(2+), MA, polyethylene glycol and various solutes were investigated. The most favorable condition tested consists of 100 mM NaCl, 1 mM Mg(2+), 5 mM MA, and 4 °C temperature, whereas the addition of Mg(2+)-chelating solutes, such as citrate, tRNAs, aspartic acid, and nucleoside triphosphates severely inhibits the reaction. These results further solidify the RNA-lipid world hypothesis and stress the importance of using a systems chemistry approach whereby a wide range of prebiotic factors interfacing with ribozymes are considered.

  19. Is the activated partial thromboplastin time suitable to screen for von Willebrand factor deficiencies?

    PubMed

    Lippi, Giuseppe; Franchini, Massimo; Poli, Giovanni; Salvagno, Gian Luca; Montagnana, Martina; Guidi, Gian Cesare

    2007-06-01

    The diagnostic approach to von Willebrand factor deficiencies is challenging and requires discretionary use of laboratory resources. Although extensive preoperative testing is not recommended, the activated partial thromboplastin time may be useful, especially in selected categories of patients. To establish the diagnostic sensitivity of this test to identify isolate von Willebrand factor deficiencies, 204 consecutive patients underwent a routine preoperative screening consisting of activated partial thromboplastin time, von Willebrand factor antigen, intrinsic pathway clotting factors activity, lupus anticoagulants and thrombin time. Thirty-seven patients were diagnosed with haemostasis disturbances other than von Willebrand factor deficiencies and were excluded from the evaluation. Isolated von Willebrand factor deficiency was diagnosed in 11 of the remaining 167 patients. A significant correlation was observed between von Willebrand factor antigen and activated partial thromboplastin time. Receiver operating characteristic curve analysis showed an area under the curve of 0.982 (95% confidence interval: 0.972-0.992; P < 0.001). At the 1.17 upper limit of the activated partial thromboplastin time, sensitivity and specificity were 100 and 85%, respectively, with negative and positive predictive values of 100 and 31%, respectively. These results demonstrate that activated partial thromboplastin time has an excellent diagnostic sensitivity and a satisfactory specificity for identifying isolated von Willebrand factor deficiencies.

  20. Some Effects of Calcium on the Activation of Human Factor VIII/Von Willebrand Factor Protein by Thrombin

    PubMed Central

    Switzer, Mary Ellen; McKee, Patrick A.

    1977-01-01

    When Factor VIII/von Willebrand factor (FVIII/vWF) protein is rechromatographed on 4% agarose in 0.25 M CaCl2, the protein and vWF activity appear in the void volume, but most of the FVIII procoagulant activity elutes later. Recent evidence suggests that the delayed FVIII procoagulant activity is a proteolytically modified form of FVIII/vWF protein that filters anomalously from agarose in 0.25 M CaCl2. To test whether or not thrombin is the protease involved, the effect of 0.25 M CaCl2 on FVIII/vWF and its reaction with thrombin was examined. About 30% of the FVIII procoagulant activity was lost immediately when solutions of FVIII/vWF protein were made 0.25 M in CaCl2. When FVIII in 0.15 M NaCl was activated with 0.04 U thrombin/ml and then made 0.25 M in CaCl2, the procoagulant activity of a broad range of FVIII/vWF protein concentrations remained activated for at least 6 h. But, in 0.25 M CaCl2, the increase in FVIII procoagulant activity in response to thrombin was much more gradual and once activated, the procoagulant activity was stabilized by 0.25 M CaCl2. When thrombin-activated FVIII/vWF protein was filtered on 4% agarose in 0.15 M NaCl, there was considerable inactivation of FVIII procoagulant activity; however, the procoagulant activity that did remain eluted in the void volume. In contrast, when thrombin-activated FVIII/vWF protein was filtered in 0.25 M CaCl2, the FVIII procoagulant activity eluted well after the void volume and remained activated for 6 h. The procoagulant peak isolated by filtering nonthrombin-activated FVIII/vWF protein on agarose in 0.25 M CaCl2 was compared to that isolated from thrombin-activated FVIII/vWF protein. Both procoagulant activity peak proteins had about the same specific vWF activity as the corresponding void volume protein. Before reduction, the sodium dodecyl sulfate gel patterns for the two procoagulant activity peak proteins were the same. After reduction, the gel pattern for the nonthrombin-activated procoagulant

  1. Hypoxic preconditioning decreases nuclear factor κB activity via Disrupted in Schizophrenia-1.

    PubMed

    Liu, Jia-Ren; Liu, Qian; Khoury, Joseph; Li, Yue-Jin; Han, Xiao-Hui; Li, Jing; Ibla, Juan C

    2016-01-01

    Nuclear factor κB is a key mediator of inflammation during conditions of hypoxia. Here, we used models of hypoxic pre-conditioning as mechanism to decrease nuclear factor κB activity induced by hypoxia. Our initial studies suggested that Disrupted in Schizophrenia-1 may be induced by hypoxic pre-conditioning and possibly involved in the regulation of nuclear factor κB. In this study we used Disrupted in Schizophrenia-1 exogenous over-expression and knock-down to determine its effect on ataxia telangiectasia mutated--nuclear factor κB activation cascade. Our results demonstrated that hypoxic pre-conditioning significantly increased the expression of Disrupted in Schizophrenia-1 at mRNA and protein levels both in vitro and in vivo. Over-expression of Disrupted in Schizophrenia-1 significantly attenuated the hypoxia-mediated ataxia telangiectasia mutated phosphorylation and prevented its cytoplasm translocation where it functions to activate nuclear factor κB. We further determined that Disrupted in Schizophrenia-1 activated the protein phosphatase 2A, preventing the phosphorylation of ataxia telangiectasia mutated serine-1981, the main regulatory site of ataxia telangiectasia mutated activity. Cellular levels of Disrupted in Schizophrenia-1 protein significantly decreased nuclear factor κB activation profiles and pro-inflammatory gene expression. Taken together, these results demonstrate that hypoxic pre-conditioning decreases the activation of nuclear factor κB through the transcriptional induction of Disrupted in Schizophrenia-1.

  2. Brain-derived neurotrophic factor and epidermal growth factor activate neuronal m-calpain via mitogen-activated protein kinase-dependent phosphorylation.

    PubMed

    Zadran, Sohila; Jourdi, Hussam; Rostamiani, Karoline; Qin, Qingyu; Bi, Xiaoning; Baudry, Michel

    2010-01-20

    Calpain is a calcium-dependent protease that plays a significant role in synaptic plasticity, cell motility, and neurodegeneration. Two major calpain isoforms are present in brain, with mu-calpain (calpain1) requiring micromolar calcium concentrations for activation and m-calpain (calpain2) needing millimolar concentrations. Recent studies in fibroblasts indicate that epidermal growth factor (EGF) can activate m-calpain independently of calcium via mitogen-activated protein kinase (MAPK)-mediated phosphorylation. In neurons, MAPK is activated by both brain-derived neurotrophic factor (BDNF) and EGF. We therefore examined whether these growth factors could activate m-calpain by MAPK-dependent phosphorylation using cultured primary neurons and HEK-TrkB cells, both of which express BDNF and EGF receptors. Calpain activation was monitored by quantitative analysis of spectrin degradation and by a fluorescence resonance energy transfer (FRET)-based assay, which assessed the truncation of a calpain-specific peptide flanked by the FRET fluorophore pair DABCYL and EDANS. In both cell types, BDNF and EGF rapidly elicited calpain activation, which was completely blocked by MAPK and calpain inhibitors. BDNF stimulated m-calpain but not mu-calpain serine phosphorylation, an effect also blocked by MAPK inhibitors. Remarkably, BDNF- and EGF-induced calpain activation was preferentially localized in dendrites and dendritic spines of hippocampal neurons and was associated with actin polymerization, which was prevented by calpain inhibition. Our results indicate that, in cultured neurons, both BDNF and EGF activate m-calpain by MAPK-mediated phosphorylation. These results strongly support a role for calpain in synaptic plasticity and may explain why m-calpain, although widely expressed in CNS, requires nonphysiological calcium levels for activation.

  3. Nuclear actin activates human transcription factor genes including the OCT4 gene.

    PubMed

    Yamazaki, Shota; Yamamoto, Koji; Tokunaga, Makio; Sakata-Sogawa, Kumiko; Harata, Masahiko

    2015-01-01

    RNA microarray analyses revealed that nuclear actin activated many human transcription factor genes including OCT4, which is required for gene reprogramming. Oct4 is known to be activated by nuclear actin in Xenopus oocytes. Our findings imply that this process of OCT4 activation is conserved in vertebrates and among cell types and could be used for gene reprogramming of human cells.

  4. Factors Predicting Behavioral Response to a Physical Activity Intervention among Adolescent Females

    ERIC Educational Resources Information Center

    Dunton, Genevieve Fridlund; Schneider, Margaret; Cooper, Dan M.

    2007-01-01

    Objective: To determine whether individual factors influenced rates of physical activity change in response to a school-based intervention. Methods: Sedentary adolescent females (N = 63) participated in a 9-month physical activity program. Weekly levels of leisure-time physical activity were reported using an interactive website. Results: Change…

  5. Exploring Contextual Factors and Patient Activation: Evidence from a Nationally Representative Sample of Patients with Depression

    ERIC Educational Resources Information Center

    Chen, Jie; Mortensen, Karoline; Bloodworth, Robin

    2014-01-01

    Patient activation has been considered as a "blockbuster drug of the century." Patients with mental disorders are less activated compared to patients with other chronic diseases. Low activation due to mental disorders can affect the efficiency of treatment of other comorbidities. Contextual factors are significantly associated with…

  6. Factors Associated with High Levels of Physical Activity among Adults with Intellectual Disability

    ERIC Educational Resources Information Center

    Temple, Viviene A.

    2009-01-01

    The aim was to identify factors associated with physical activity participation among active (i.e. more than or equal to 10 000 steps per day) individuals with intellectual disability. Staff at day program and supported employment organizations were asked to identify individuals they believed were physically active. To verify participants were…

  7. Predicting involvement in prison gang activity: street gang membership, social and psychological factors.

    PubMed

    Wood, Jane L; Alleyne, Emma; Mozova, Katarina; James, Mark

    2014-06-01

    The aim of this study was to examine whether street gang membership, psychological factors, and social factors such as preprison experiences could predict young offenders' involvement in prison gang activity. Data were collected via individual interviews with 188 young offenders held in a Young Offenders Institution in the United Kingdom. Results showed that psychological factors such as the value individuals attached to social status, a social dominance orientation, and antiauthority attitudes were important in predicting young offenders' involvement in prison gang activity. Further important predictors included preimprisonment events such as levels of threat, levels of individual delinquency, and levels of involvement in group crime. Longer current sentences also predicted involvement in prison gang activity. However, street gang membership was not an important predictor of involvement in prison gang activity. These findings have implications for identifying prisoners involved in prison gang activity and for considering the role of psychological factors and group processes in gang research.

  8. Gastric secretion of platelet activating factor and precursors in healthy humans: effect of pentagastrin.

    PubMed Central

    Sobhani, I; Denizot, Y; Hochlaf, S; Rigaud, D; Vatier, J; Benveniste, J; Lewin, M J; Mignon, M

    1993-01-01

    The release of platelet activating factor (PAF-ACETHER or PAF) and its precursors in the gastric lumen was assessed in 13 normal subjects in basal condition and after stimulation by gastrin. Acid, pepsin, and sialic acid outputs were determined under the same conditions. Gastric juice was collected using a nasogastric tube after overnight fast in basal condition for 60 minutes, then under pentagastrin infusion (6 micrograms/kg/hr for 60 minutes). Platelet activating factor was detected at low concentration in 4/13 subjects under basal condition (mean (SEM) 1.2 (0.6) pg/hr) while high concentrations of lyso platelet activating factor (6.1 (1.8) microgram/hr) and of alkyl-acyl-glycerophosphocholine (AAGPC) (11.5 (3) micrograms/hr) were found in 13 and 11 subjects, respectively. Platelet activating factor was not detected during pentagastrin infusion, while lyso platelet activating factor and alkyl-acyl-glycerophosphocholine were detected in 13 and in 12 subjects, respectively. Compared with the basal condition these platelet activating factor precursors increased significantly (p < 0.001) going up to fivefold baseline (31.8 (6.8) micrograms/hr and 53 (9.3) micrograms/hr respectively) in response to pentagastrin. There was a positive correlation between platelet activating factor precursors and acid or pepsin output but not between platelet activating factor precursors and sialic acid. As sialic acid may be considered an index of mucus glycoprotein degradation, it seems that gastrin stimulation of gastric epithelial cells results in a concomittant secretion of platelet activating factor precursors, acid, and pepsin irrespective of mucus glycoprotein degradation. PMID:8174952

  9. Functional Interplay between CBP and PCAF in Acetylation and Regulation of Transcription Factor KLF13 Activity

    PubMed Central

    Song, Chao-Zhong; Keller, Kimberly; Chen, Yangchao; Stamatoyannopoulos, George

    2010-01-01

    The transcriptional co-activators CBP/p300 and PCAF participate in transcriptional activation by many factors. We have shown that both CBP/p300 and PCAF stimulate the transcriptional activation by KLF13, a member of the KLF/Sp1 family, either individually or cooperatively. Here we further investigated how CBP and PCAF acetylation regulate KLF13 activity, and how these two co-activators functionally interplay in the regulation of KLF13 activity. We found that CBP and PCAF acetylated KLF13 at specific lysine residues in the zinc finger domain of KLF13. The acetylation by CBP, however, resulted in disruption of KLF13 DNA binding. Although the acetyltransferase activity of CBP is not required for stimulating the DNA binding activity of all of the transcription factors that we have examined, the disruption of factor DNA binding by CBP acetylation is factor-specific. We further showed that PCAF and CBP act synergistically and antagonistically to regulate KLF13 DNA binding depending on the status of acetylation. PCAF blocked CBP acetylation and disruption of KLF13 DNA binding. Conversely, acetylation of KLF13 by CBP prevented PCAF stimulation of KLF13 DNA binding. PCAF blocked CBP disruption of KLF13 DNA binding by preventing CBP acetylation of KLF13. These results demonstrate that acetylation by CBP has distinct effects on transcription factor DNA binding, and that CBP and PCAF regulate each other functionally in their regulation of transcription factor DNA binding. PMID:12758070

  10. A human factors evaluation of Extravehicular Activity gloves

    NASA Technical Reports Server (NTRS)

    O'Hara, John M.; Briganti, Michael; Cleland, John; Winfield, Dan

    1989-01-01

    One of the major problems faced in Extravehicular Activity (EVA) glove development has been the absence of concise and reliable methods to measure the effects of EVA gloves on human-hand capabilities. NASA has sponsored a program to develop a standardized set of tests designed to assess EVA-gloved hand capabilities in six performance domains: Range of Motion, Strength, Tactile Perception, Dexterity, Fatigue, and Comfort. Based upon an assessment of general human-hand functioning and EVA task requirements, several tests within each performance domain were developed to provide a comprehensive evaluation. All tests were designed to be conducted in a glove box with the bare hand, an EVA glove without pressure, an EVA glove at operation pressure. Thus, the differential effect on performance of the glove with and without pressure was tested. Bare hand performance was used to 'calibrate' the effects. Ten subjects participated in the test setup as a repeated-measures experimental design. The paper will report the results of the test program.

  11. Sexual activity and cardiac risk: is depression a contributing factor?

    PubMed

    Roose, S P; Seidman, S N

    2000-07-20

    There is a well-documented association between depression, ischemic heart disease, and cardiovascular mortality. This association has a number of dimensions including: (1) depressed patients have a higher than expected rate of sudden cardiovascular death; (2) over the course of a lifetime, patients with depression develop symptomatic and fatal ischemic heart disease at a higher rate compared with a nondepressed group; and (3) depression after myocardial infarction (MI) is associated with increased cardiac mortality. Depression is also associated with sexual dysfunction, particularly erectile dysfunction. If depression is the primary illness, then erectile dysfunction can be considered a symptom of the depressive illness. However, if the erectile dysfunction is primary, men may develop a depressive syndrome in reaction to the loss of sexual function. Regardless of whether erectile dysfunction is a symptom of depression or depression is a consequence of erectile dysfunction, these conditions are frequently comorbid. Thus, the patient with ischemic heart disease who is depressed is more likely to have erectile difficulties. An attempt by this patient to engage in sexual activity is therefore more likely to be unsuccessful and, given the increase in cardiac mortality associated with depression, it may result in a serious cardiac event.

  12. Neurotrophic factors [activity-dependent neurotrophic factor (ADNF) and basic fibroblast growth factor (bFGF)] interrupt excitotoxic neurodegenerative cascades promoted by a PS1 mutation

    PubMed Central

    Guo, Qing; Sebastian, Lois; Sopher, Bryce L.; Miller, Miles W.; Glazner, Gordon W.; Ware, Carol B.; Martin, George M.; Mattson, Mark P.

    1999-01-01

    Although an excitotoxic mechanism of neuronal injury has been proposed to play a role in chronic neurodegenerative disorders such as Alzheimer’s disease, and neurotrophic factors have been put forward as potential therapeutic agents, direct evidence is lacking. Taking advantage of the fact that mutations in the presenilin-1 (PS1) gene are causally linked to many cases of early-onset inherited Alzheimer’s disease, we generated PS1 mutant knock-in mice and directly tested the excitotoxic and neurotrophic hypotheses of Alzheimer’s disease. Primary hippocampal neurons from PS1 mutant knock-in mice exhibited increased production of amyloid β-peptide 42/43 and increased vulnerability to excitotoxicity, which occurred in a gene dosage-dependent manner. Neurons expressing mutant PS1 exhibited enhanced calcium responses to glutamate and increased oxyradical production and mitochondrial dysfunction. Pretreatment with either basic fibroblast growth factor or activity-dependent neurotrophic factor protected neurons expressing mutant PS1 against excitotoxicity. Both basic fibroblast growth factor and activity-dependent neurotrophic factor stabilized intracellular calcium levels and abrogated the increased oxyradical production and mitochondrial dysfunction otherwise caused by the PS1 mutation. Our data indicate that neurotrophic factors can interrupt excitotoxic neurodegenerative cascades promoted by PS1 mutations. PMID:10097174

  13. Altered activities of transcription factors and their related gene expression in cardiac tissues of diabetic rats.

    PubMed

    Nishio, Y; Kashiwagi, A; Taki, H; Shinozaki, K; Maeno, Y; Kojima, H; Maegawa, H; Haneda, M; Hidaka, H; Yasuda, H; Horiike, K; Kikkawa, R

    1998-08-01

    Gene regulation in the cardiovascular tissues of diabetic subjects has been reported to be altered. To examine abnormal activities in transcription factors as a possible cause of this altered gene regulation, we studied the activity of two redox-sensitive transcription factors--nuclear factor-kappaB (NF-kappaB) and activating protein-1 (AP-1)--and the change in the mRNA content of heme oxygenase-1, which is regulated by these transcription factors in the cardiac tissues of rats with streptozotocin-induced diabetes. Increased activity of NF-kappaB and AP-1 but not nuclear transcription-activating factor, as determined by an electrophoretic mobility shift assay, was found in the hearts of 4-week diabetic rats. Glycemic control by a subcutaneous injection of insulin prevented these diabetes-induced changes in transcription factor activity. In accordance with these changes, the mRNA content of heme oxygenase-1 was increased fourfold in 4-week diabetic rats and threefold in 24-week diabetic rats as compared with control rats (P < 0.01 and P < 0.05, respectively). Insulin treatment also consistently prevented changes in the mRNA content of heme oxygenase-1. The oral administration of an antioxidant, probucol, to these diabetic rats partially prevented the elevation of the activity of both NF-kappaB and AP-1, and normalized the mRNA content of heme oxygenase-1 without producing any change in the plasma glucose concentration. These results suggest that elevated oxidative stress is involved in the activation of the transcription factors NF-kappaB and AP-1 in the cardiac tissues of diabetic rats, and that these abnormal activities of transcription factors could be associated with the altered gene regulation observed in the cardiovascular tissues of diabetic rats.

  14. Production and functional activity of a recombinant von Willebrand factor-A domain from human complement factor B.

    PubMed Central

    Williams, S C; Hinshelwood, J; Perkins, S J; Sim, R B

    1999-01-01

    Factor B is a five-domain 90 kDa serine protease proenzyme which is part of the human serum complement system. It binds to other complement proteins C3b and properdin, and is activated by the protease factor D. The fourth domain of factor B is homologous to the type A domain of von Willebrand Factor (vWF-A). A full-length human factor B cDNA clone was used to amplify the region encoding the vWF-A domain (amino acids 229-444 of factor B). A fusion protein expression system was then used to generate it in high yield in Escherichia coli, where thrombin cleavage was used to separate the vWF-A domain from its fusion protein partner. A second vWF-A domain with improved stability and solubility was created using a Cys(267)-->Ser mutation and a four-residue C-terminal extension of the first vWF-A domain. The recombinant domains were investigated by analytical gel filtration, sucrose density centrifugation and analytical ultracentrifugation, in order to show that both domains were monomeric and possessed compact structures that were consistent with known vWF-A crystal structures. This expression system and its characterization permitted the first investigation of the function of the isolated vWF-A domain. It was able to inhibit substantially the binding of (125)I-labelled factor B to immobilized C3b. This demonstrated both the presence of a C3b binding site in this portion of factor B and a ligand-binding property of the vWF-A domain. The site at which factor D cleaves factor B is close to the N-terminus of both recombinant vWF-A domains. Factor D was shown to cleave the vWF-A domain in the presence or absence of C3b, whereas the cleavage of intact factor B under the same conditions occurs only in the presence of C3b. PMID:10477273

  15. Tcra enhancer activation by inducible transcription factors downstream of pre-TCR signaling.

    PubMed

    del Blanco, Beatriz; García-Mariscal, Alberto; Wiest, David L; Hernández-Munain, Cristina

    2012-04-01

    The Tcra enhancer (Eα) is essential for pre-TCR-mediated activation of germline transcription and V(D)J recombination. Eα is considered an archetypical enhanceosome that acts through the functional synergy and cooperative binding of multiple transcription factors. Based on dimethylsulfate genomic footprinting experiments, there has been a long-standing paradox regarding Eα activation in the absence of differences in enhancer occupancy. Our data provide the molecular mechanism of Eα activation and an explanation of this paradox. We found that germline transcriptional activation of Tcra is dependent on constant phospholipase Cγ, as well as calcineurin- and MAPK/ERK-mediated signaling, indicating that inducible transcription factors are crucially involved. NFAT, AP-1, and early growth response factor 1, together with CREB-binding protein/p300 coactivators, bind to Eα as part of an active enhanceosome assembled during pre-TCR signaling. We favor a scenario in which the binding of lymphoid-restricted and constitutive transcription factors to Eα prior to its activation forms a regulatory scaffold to recruit factors induced by pre-TCR signaling. Thus, the combinatorial assembly of tissue- and signal-specific transcription factors dictates the Eα function. This mechanism for enhancer activation may represent a general paradigm in tissue-restricted and stimulus-responsive gene regulation.

  16. Phosphoinositide 3-Kinases Upregulate System xc− via Eukaryotic Initiation Factor 2α and Activating Transcription Factor 4 – A Pathway Active in Glioblastomas and Epilepsy

    PubMed Central

    Baxter, Paul; Kassubek, Rebecca; Albrecht, Philipp; Van Liefferinge, Joeri; Westhoff, Mike-Andrew; Halatsch, Marc-Eric; Karpel-Massler, Georg; Meakin, Paul J.; Hayes, John D.; Aronica, Eleonora; Smolders, Ilse; Ludolph, Albert C.; Methner, Axel; Conrad, Marcus; Massie, Ann; Hardingham, Giles E.

    2014-01-01

    Abstract Aims: Phosphoinositide 3-kinases (PI3Ks) relay growth factor signaling and mediate cytoprotection and cell growth. The cystine/glutamate antiporter system xc− imports cystine while exporting glutamate, thereby promoting glutathione synthesis while increasing extracellular cerebral glutamate. The aim of this study was to analyze the pathway through which growth factor and PI3K signaling induce the cystine/glutamate antiporter system xc− and to demonstrate its biological significance for neuroprotection, cell growth, and epilepsy. Results: PI3Ks induce system xc− through glycogen synthase kinase 3β (GSK-3β) inhibition, general control non-derepressible-2-mediated eukaryotic initiation factor 2α phosphorylation, and the subsequent translational up-regulation of activating transcription factor 4. This pathway is essential for PI3Ks to modulate oxidative stress resistance of nerve cells and insulin-induced growth in fibroblasts. Moreover, the pathway is active in human glioblastoma cells. In addition, it is induced in primary cortical neurons in response to robust neuronal activity and in hippocampi from patients with temporal lobe epilepsy. Innovation: Our findings further extend the concepts of how growth factors and PI3Ks induce neuroprotection and cell growth by adding a new branch to the signaling network downstream of GSK-3β, which, ultimately, leads to the induction of the cystine/glutamate antiporter system xc−. Importantly, the induction of this pathway by neuronal activity and in epileptic hippocampi points to a potential role in epilepsy. Conclusion: PI3K-regulated system xc− activity is not only involved in the stress resistance of neuronal cells and in cell growth by increasing the cysteine supply and glutathione synthesis, but also plays a role in the pathophysiology of tumor- and non-tumor-associated epilepsy by up-regulating extracellular cerebral glutamate. Antioxid. Redox Signal. 20: 2907–2922. PMID:24219064

  17. Mammary tumorigenesis induced by fibroblast growth factor receptor 1 requires activation of the epidermal growth factor receptor.

    PubMed

    Bade, Lindsey K; Goldberg, Jodi E; Dehut, Hazel A; Hall, Majken K; Schwertfeger, Kathryn L

    2011-09-15

    Fibroblast growth factor receptor 1 (FGFR1) is an oncoprotein with known involvement in mammary tumorigenesis. To understand how FGFR1 signaling promotes mammary tumorigenesis, an inducible FGFR1 (iFGFR1) system was created previously. Previous studies have demonstrated that upon iFGFR1 activation in vivo, the epidermal growth factor (EGF) ligands amphiregulin (AREG) and epiregulin (EREG) are upregulated. Both AREG and EREG interact with the EGF receptor (EGFR). Here, we investigated whether the FGFR1-induced increase in AREG and EREG expression might coordinately increase EGFR signaling to promote mammary tumorigenesis. Treatment of mouse mammary epithelial cells with either AREG or EREG conferred a greater migratory potential, increased cellular proliferation and increased extracellular regulated kinase 1/2 (ERK1/2) activation. These effects could be blocked with the EGFR-specific inhibitor erlotinib, suggesting that they are EGFR-dependent. In transgenic mice with iFGFR1 under the control of the mouse mammary tumor virus (MMTV) promoter, iFGFR1 activation also led to increased mammary epithelial cell proliferation that was inhibited with erlotinib. Taken together, these data suggest that AREG and EREG mediate tumorigenic phenotypes by activating EGFR signaling, and that the oncogenic potential of FGFR1 requires EGFR activation to promote mammary tumorigenesis.

  18. The ETS Factor Myeloid Elf-1-Like Factor (MEF)/Elf4 Is Transcriptionally and Functionally Activated by Hypoxia.

    PubMed

    Suico, Mary Ann; Taura, Manabu; Kudo, Eriko; Gotoh, Kumiko; Shuto, Tsuyoshi; Okada, Seiji; Kai, Hirofumi

    2016-01-01

    Hypoxia-inducible factor (HIF)-1α is a transcription factor belonging to the HIF family that is activated in mammalian cells during conditions of low oxygen tension or hypoxia to induce an adaptive response and promote cell survival. Some of the genes targeted by HIF-1α are important for angiogenesis and proliferation. Here, we found that the E26 transformation-specific (ETS) transcription factor myeloid elf-1-like factor (MEF)/Elf4 is activated by HIF-1α. MEF induces genes such as human beta-defensin 2 (HβD2) and perforin (PRF1), and is known to affect the cell cycle. Treatment with hypoxia mimetic CoCl2 or low O2 incubation up-regulated MEF mRNA and protein levels in various cell lines. HIF-1α overexpression in HEK293 cells also increased MEF mRNA and protein levels. In contrast, HIF-1α knockdown by small interfering RNA (siRNA) suppressed the induction of MEF in response to hypoxia. HIF-1α binds to the hypoxia response element in the MEF promoter region (-200 bp) and activates MEF promoter under hypoxia condition. The induction of MEF by hypoxia/HIF-1α correlated with the increase of MEF target genes HβD2 and PRF1. Intriguingly, the hypoxia-induced expression of HIF-1α target gene vascular endothelial growth factor (VEGF) was enhanced by the exogenous addition of MEF. Overall, these data indicate that hypoxia or HIF-1α positively regulates MEF expression and function.

  19. Building predictive gene signatures through simultaneous assessment of transcription factor activation and gene expression.

    EPA Science Inventory

    Building predictive gene signatures through simultaneous assessment of transcription factor activation and gene expression Exposure to many drugs and environmentally-relevant chemicals can cause adverse outcomes. These adverse outcomes, such as cancer, have been linked to mol...

  20. The contribution of home, neighbourhood and school environmental factors in explaining physical activity among adolescents.

    PubMed

    Haerens, Leen; Craeynest, Mietje; Deforche, Benedicte; Maes, Lea; Cardon, Greet; De Bourdeaudhuij, Ilse

    2009-01-01

    The present study aimed at investigating the influence of home, neighbourhood and school environmental factors on adolescents' engagement in self-reported extracurricular physical activity and leisure time sports and on MVPA objectively measured by accelerometers. Environmental factors were assessed using questionnaires. Gender specific hierarchical regression analyses were conducted, with demographic variables entered in the first block, and environmental, psychosocial factors and interactions terms entered in the second block. Participation in extracurricular activities at school was positively related to the number of organized activities and the provision of supervision. Perceived accessibility of neighborhood facilities was not related to engagement in leisure time sports, whereas the availability of sedentary and physical activity equipment was. Findings were generally supportive of ecological theories stating that behaviors are influenced by personal and environmental factors that are constantly interacting.

  1. Factors associated with physical activity among young adults with a disability.

    PubMed

    Saebu, M; Sørensen, M

    2011-10-01

    The purpose of this study was to examine: (1) total physical activity and (2) the relative importance of functioning and disability, environmental and personal factors for total physical activity among young adults with a disability. The International Classification of Functioning, Disability and Health developed by the World Health Organization was used as a structural framework for a cross-sectional survey, based on a questionnaire. The population studied was 327 young adults (age 18-30) with a disability who were members of interest organizations for persons with disabilities. Using an adapted version of the self-administered short form of International Physical Activity Questionnaire (IPAQ), the sample reported some differences in physical activity related to the type and the onset of disability. Linear regression analyses revealed that personal factors demonstrated more power in explaining the variance in physical activity than both the environmental factors and factors related to functioning and disability. As for the able-bodied, intrinsic motivation and identity as an active person were the factors most strongly associated with physical activity behavior. This should have important consequences for how professionals try to motivate people with disabilities for physical activity, and how they plan and implement rehabilitation.

  2. Identification of platelet-activating factor acetylhydrolase II in human skin.

    PubMed

    Marques, Mariangela; Pei, Yong; Southall, Michael D; Johnston, John M; Arai, Hiroyuki; Aoki, Junken; Inoue, Takao; Seltmann, Holger; Zouboulis, Christos C; Travers, Jeffrey B

    2002-10-01

    Platelet-activating factor acetylhydrolases are a family of specialized phospholipase A2 enzymes. They serve an anti-inflammatory function by converting the proinflammatory autocoid, PAF, into biologically inactive lyso-PAF, by the removal of the sn-2 acetyl group of this glycerophospholipid. Similarly, platelet-activating factor acetylhydrolases can also degrade oxidatively modified sn-2 polyunsaturated-fatty-acid-containing phospholipids, which are toxic to cells. Platelet-activating factor acetylhydrolase II is a recently cloned member of this family of specialized phospholipases. Consistent with a potential role of this intracellular enzyme in protecting membrane phospholipids against oxidative stress, platelet-activating factor acetylhydrolase II has been shown to translocate from cytosol to membranes in response to pro-oxidative stressors, and overexpression of this enzyme decreases the cytotoxic effects of these agents. The objective of this study was to assess whether platelet-activating factor acetylhydrolase II is involved in protecting skin against oxidative stress. Platelet-activating factor acetylhydrolase II protein was demonstrated in human skin by immunohistochemistry, with the highest levels of the enzyme found in sebaceous glands and lesser amounts in epidermal keratinocytes. Treatment of epidermal cells with t-butylhydroperoxide or ultraviolet B radiation resulted in platelet-activating factor acetylhydrolase II translocation from cytosol to membranes. To assess the role of this enzyme in epidermal function, a recombinant retroviral strategy was used to overexpress platelet-activating factor acetylhydrolase II in the human keratinocyte-derived cell line HaCaT. Overexpression of platelet-activating factor acetylhydrolase II protected HaCaT cells against apop tosis induced by oxidative stressors t-butylhydroperoxide and ultraviolet B radiation. Similar levels of apoptosis, however, were seen in both control and platelet-activating-factor

  3. Hypoxia-Inducible Factor 1 Is an Inductor of Transcription Factor Activating Protein 2 Epsilon Expression during Chondrogenic Differentiation.

    PubMed

    Niebler, Stephan; Angele, Peter; Kujat, Richard; Bosserhoff, Anja K

    2015-01-01

    The transcription factor AP-2ε (activating enhancer-binding protein epsilon) is expressed in cartilage of humans and mice. However, knowledge about regulatory mechanisms influencing AP-2ε expression is limited. Using quantitative real time PCR, we detected a significant increase in AP-2ε mRNA expression comparing initial and late stages of chondrogenic differentiation processes in vitro and in vivo. Interestingly, in these samples the expression pattern of the prominent hypoxia marker gene angiopoietin-like 4 (Angptl4) strongly correlated with that of AP-2ε suggesting that hypoxia might represent an external regulator of AP-2ε expression in mammals. In order to show this, experiments directly targeting the activity of hypoxia-inducible factor-1 (HIF1), the complex mediating responses to oxygen deprivation, were performed. While the HIF1-activating compounds 2,2'-dipyridyl and desferrioxamine resulted in significantly enhanced mRNA concentration of AP-2ε, siRNA against HIF1α led to a significantly reduced expression rate of AP-2ε. Additionally, we detected a significant upregulation of the AP-2ε mRNA level after oxygen deprivation. In sum, these different experimental approaches revealed a novel role for the HIF1 complex in the regulation of the AP-2ε gene in cartilaginous cells and underlined the important role of hypoxia as an important external regulatory stimulus during chondrogenic differentiation modulating the expression of downstream transcription factors.

  4. Role of platelet activating factor in pathogenesis of acute pancreatitis in rats.

    PubMed Central

    Konturek, S J; Dembinski, A; Konturek, P J; Warzecha, Z; Jaworek, J; Gustaw, P; Tomaszewska, R; Stachura, J

    1992-01-01

    The importance of platelet activating factor in acute pancreatitis was examined by determining the tissue content of endogenous platelet activating factor and the protective effects of TCV-309, a highly selective platelet activating factor blocker, against caerulein induced pancreatitis in rats. Infusion of caerulein (10 micrograms/kg/h) for five hours resulted in about 70% increase in pancreatic weight, 22% rise in protein content, 50% reduction in tissue blood flow, nine fold increase in tissue level of platelet activating factor and 165% rise in plasma amylase as well as histological evidence of acute pancreatitis. Such infusion of caerulein in chronic pancreatic fistula rats caused a marked increase in protein output from basal secretion of 10 mg/30 minutes to 40 mg/30 minutes in the first hour of infusion followed by a decline in protein output to 15-20 mg/30 minutes in the following hours of the experiment. Exogenous platelet activating factor (50 micrograms/kg) injected ip produced similar alterations in weight, protein content, blood flow, and histology of the pancreas but the increment in serum amylase was significantly smaller and pancreatic secretion was reduced below the basal level. TCV-309 (50 micrograms/kg) given ip before caerulein or platelet activating factor administration significantly reduced the biochemical and morphological alterations caused by caerulein and abolished those induced by exogenous platelet activating factor. These results indicate that platelet activating factor plays an important role in the pathogenesis of acute pancreatitis probably by reducing the blood flow and increasing vascular permeability in the pancreas. PMID:1385272

  5. Role of platelet activating factor in pathogenesis of acute pancreatitis in rats.

    PubMed

    Konturek, S J; Dembinski, A; Konturek, P J; Warzecha, Z; Jaworek, J; Gustaw, P; Tomaszewska, R; Stachura, J

    1992-09-01

    The importance of platelet activating factor in acute pancreatitis was examined by determining the tissue content of endogenous platelet activating factor and the protective effects of TCV-309, a highly selective platelet activating factor blocker, against caerulein induced pancreatitis in rats. Infusion of caerulein (10 micrograms/kg/h) for five hours resulted in about 70% increase in pancreatic weight, 22% rise in protein content, 50% reduction in tissue blood flow, nine fold increase in tissue level of platelet activating factor and 165% rise in plasma amylase as well as histological evidence of acute pancreatitis. Such infusion of caerulein in chronic pancreatic fistula rats caused a marked increase in protein output from basal secretion of 10 mg/30 minutes to 40 mg/30 minutes in the first hour of infusion followed by a decline in protein output to 15-20 mg/30 minutes in the following hours of the experiment. Exogenous platelet activating factor (50 micrograms/kg) injected ip produced similar alterations in weight, protein content, blood flow, and histology of the pancreas but the increment in serum amylase was significantly smaller and pancreatic secretion was reduced below the basal level. TCV-309 (50 micrograms/kg) given ip before caerulein or platelet activating factor administration significantly reduced the biochemical and morphological alterations caused by caerulein and abolished those induced by exogenous platelet activating factor. These results indicate that platelet activating factor plays an important role in the pathogenesis of acute pancreatitis probably by reducing the blood flow and increasing vascular permeability in the pancreas.

  6. Rapid loss of factor XII and XI activity in ellagic acid-activated normal plasma: role of plasma inhibitors and implications for automated activated partial thromboplastin time recording.

    PubMed

    Joist, J H; Cowan, J F; Khan, M

    1977-12-01

    Rapid prolongation of the aPTT of normal plasma upon incubation with ellagic acid containing aPTT reagents was observed. The aPTT prolongation was not due to time-dependent changes in pH in the incubation mixture or loss of activity of the labile coagulation factors VIII and V but occurred as a result of rapid progressive inactivation of ellagic acid-activated factors XII and XI. Prolongation of the aPTT and loss of contact factor activities was not observed in plasma incubated with particulate activator reagents. This finding seemed to indicate that adsorption of factors XII and XI to larger particles during the activation process might protect these factors from inactivation by naturally occurring plasma inhibitors. Evidence is presented which supports previous findings that C1-INH, alpha1-AT, and antithrombin (in the presence of heparin) contribute to factor XIIa and XI a inactivation in ellagic acid-activated plasma and that plasma albumin may compete with factor XII for ellagic acid binding. The data indicate that ellagic acid-containing aPTT reagents have unfavorable properties which seriously limit their usefulness in the clinical laboratory, particularly in respect to recording of the aPTT with certain fully automated clot timers.

  7. Risk Factors for Clinically Significant Intimate Partner Violence among Active-Duty Members

    ERIC Educational Resources Information Center

    Smith Slep, Amy M.; Foran, Heather M.; Heyman, Richard E.; Snarr, Jeffery D.

    2011-01-01

    Hypothesized risk factors for men's and women's clinically significant intimate partner violence (CS-IPV) from four ecological levels (i.e., individual, family, workplace, community) were tested in a representative sample of active-duty U.S. Air Force members (N = 42,744). When considered together, we expected only individual and family factors to…

  8. Positive Feedback Loops for Factor V and Factor VII Activation Supply Sensitivity to Local Surface Tissue Factor Density During Blood Coagulation

    PubMed Central

    Balandina, A.N.; Shibeko, A.M.; Kireev, D.A.; Novikova, A.A.; Shmirev, I.I.; Panteleev, M.A.; Ataullakhanov, F.I.

    2011-01-01

    Blood coagulation is triggered not only by surface tissue factor (TF) density but also by surface TF distribution. We investigated recognition of surface TF distribution patterns during blood coagulation and identified the underlying molecular mechanisms. For these investigations, we employed 1), an in vitro reaction-diffusion experimental model of coagulation; and 2), numerical simulations using a mathematical model of coagulation in a three-dimensional space. When TF was uniformly immobilized over the activating surface, the clotting initiation time in normal plasma increased from 4 min to >120 min, with a decrease in TF density from 100 to 0.7 pmol/m2. In contrast, surface-immobilized fibroblasts initiated clotting within 3–7 min, independently of fibroblast quantity and despite a change in average surface TF density from 0.5 to 130 pmol/m2. Experiments using factor V-, VII-, and VIII-deficient plasma and computer simulations demonstrated that different responses to these two TF distributions are caused by two positive feedback loops in the blood coagulation network: activation of the TF–VII complex by factor Xa, and activation of factor V by thrombin. This finding suggests a new role for these reactions: to supply sensitivity to local TF density during blood coagulation. PMID:22004734

  9. Chromatin Remodeling Mediated by Drosophila GAGA Factor and ISWI Activates fushi tarazu Gene Transcription In Vitro

    PubMed Central

    Okada, Masahiro; Hirose, Susumu

    1998-01-01

    GAGA factor is known to remodel the chromatin structure in concert with nucleosome-remodeling factor NURF in a Drosophila embryonic S150 extract. The promoter region of the Drosophila fushi tarazu (ftz) gene carries several binding sites for GAGA factor. Both the GAGA factor-binding sites and GAGA factor per se are necessary for the proper expression of ftz in vivo. We observed transcriptional activation of the ftz gene when a preassembled chromatin template was incubated with GAGA factor and the S150 extract. The chromatin structure within the ftz promoter was specifically disrupted by incubation of the preassembled chromatin with GAGA factor and the S150 extract. Both transcriptional activation and chromatin disruption were blocked by an antiserum raised against ISWI or by base substitutions in the GAGA factor-binding sites in the ftz promoter region. These results demonstrate that GAGA factor- and ISWI-mediated disruption of the chromatin structure within the promoter region of ftz activates transcription on the chromatin template. PMID:9566866

  10. Factors Involved in Iranian Women Heads of Household's Health Promotion Activities: A Grounded Theory Study.

    PubMed

    Rafii, Forough; Seyedfatemi, Naima; Rezaei, Mahboubeh

    2013-01-01

    We aimed to explore and describe the factors involved in Iranian women heads of household's health promotion activities. Grounded theory was used as the method. Sixteen women heads of household were recruited. Data were generated by semi structured interviews. Our findings indicated that remainder of resources (money, time and energy) alongside perceived severity of health risk were two main factors whereas women's personal and socio-economic characteristics were two contextual factors involved in these women's health promotion activities. To help these women improve their health status, we recommended that the government, non-governmental organizations and health care professionals provide them with required resources and increase their knowledge by holding training sessions.

  11. Physical Activity Trajectories and Multi-Level Factors among Adolescent Girls

    PubMed Central

    Zook, Kathleen R.; Saksvig, Brit I.; Wu, Tong Tong

    2013-01-01

    Purpose Although the decline of physical activity in adolescent girls is well-documented, there are girls whose physical activity does not follow this pattern. This study examined the relationships between physical activity trajectories and personal, psychosocial and environmental factors among adolescent girls. Methods Participants were from the University of Maryland field site of the Trial of Activity for Adolescent Girls. Of 730 girls measured in 8th grade, 589 were re-measured in 11th grade. Moderate to vigorous physical activity was assessed by accelererometers; participants were categorized as active maintainers (n=31), inactive maintainers (n=410), adopters (n=64), or relapsers (n=56). Height and weight were measured, personal and psychosocial information was collected from surveys, and distance from home to school and parks was assessed from Geographical Information Systems. Multivariable logistic regression was used for data analysis. Results Variables at individual, social, and environmental levels predicted active maintainers and inactive maintainers, while only individual-level variables predicted adoption. None predicted relapse. Higher (favorable) scores for physical self-concept, perceived body fat, friend and family physical activity support, frequency of physical activity with friends, and shorter distance from home to a park predicted active maintainers. Overweight/obese status, earlier age at menses, and lower scores for physical self-concept, perceived body fat, friend physical activity support, and frequency of physical activity with friends, and further distance from home to school predicted inactive maintainers. High physical self-concept and not being overweight/obese predicted adopters. Conclusion Multi-level factors appear to predict behavior maintenance rather than actual change. Implications and Contribution Although physical activity declines among girls during adolescence, some maintain and others increase their physical activity. Our

  12. Two distinct forms of Factor VIII coagulant protein in human plasma. Cleavage by thrombin, and differences in coagulant activity and association with von Willebrand factor.

    PubMed Central

    Weinstein, M J; Chute, L E

    1984-01-01

    We have characterized Factor VIII coagulant protein, present in normal human plasma, that reacts with a specific human 125I-labeled anti-human VIII:C antigen Fab antibody fragment. Two major Factor VIII coagulant antigen populations were present. The first, approximately 85% of the total antigen, was bound to von Willebrand factor and when tested in a standard one-stage assay had Factor VIII coagulant activity. The second antigenic population, eluting near fibrinogen when plasma was gel filtered, was not bound to von Willebrand protein, did not have Factor VIII coagulant activity unless activated, but did block anti-VIII:C Fab neutralization of clotting activity. The two antigenic populations were separable by cryoprecipitation and agarose gel electrophoresis. Although the two antigenic populations differed in their Factor VIII coagulant activity and in their binding to von Willebrand factor, the principal member of both populations is of mol wt 2.4 X 10(5). Both antigens, when proteolyzed by thrombin, were quickly converted to a 1 X 10(5)-mol wt form in association with the appearance of VIII:C activity. The 1 X 10(5)-mol wt antigen was further slowly degraded to an 8 X 10(4)-mol wt form while Factor VIII coagulant activity declined. These results demonstrate the presence of an inactive Factor VIII coagulant protein in plasma, not associated with von Willebrand factor, that can react with thrombin to yield Factor VIII coagulant activity. Images PMID:6421875

  13. Blockade of T-cell activation by dithiocarbamates involves novel mechanisms of inhibition of nuclear factor of activated T cells.

    PubMed Central

    Martínez-Martínez, S; Gómez del Arco, P; Armesilla, A L; Aramburu, J; Luo, C; Rao, A; Redondo, J M

    1997-01-01

    Dithiocarbamates (DTCs) have recently been reported as powerful inhibitors of NF-kappaB activation in a number of cell types. Given the role of this transcription factor in the regulation of gene expression in the inflammatory response, NF-kappaB inhibitors have been suggested as potential therapeutic drugs for inflammatory diseases. We show here that DTCs inhibited both interleukin 2 (IL-2) synthesis and membrane expression of antigens which are induced during T-cell activation. This inhibition, which occurred with a parallel activation of c-Jun transactivating functions and expression, was reflected by transfection experiments at the IL-2 promoter level, and involved not only the inhibition of NF-kappaB-driven reporter activation but also that of nuclear factor of activated T cells (NFAT). Accordingly, electrophoretic mobility shift assays (EMSAs) indicated that pyrrolidine DTC (PDTC) prevented NF-kappaB, and NFAT DNA-binding activity in T cells stimulated with either phorbol myristate acetate plus ionophore or antibodies against the CD3-T-cell receptor complex and simultaneously activated the binding of AP-1. Furthermore, PDTC differentially targeted both NFATp and NFATc family members, inhibiting the transactivation functions of NFATp and mRNA induction of NFATc. Strikingly, Western blotting and immunocytochemical experiments indicated that PDTC promoted a transient and rapid shuttling of NFATp and NFATc, leading to their accelerated export from the nucleus of activated T cells. We propose that the activation of an NFAT kinase by PDTC could be responsible for the rapid shuttling of the NFAT, therefore transiently converting the sustained transactivation of this transcription factor that occurs during lymphocyte activation, and show that c-Jun NH2-terminal kinase (JNK) can act by directly phosphorylating NFATp. In addition, the combined inhibitory effects on NFAT and NF-KB support a potential use of DTCs as immunosuppressants. PMID:9343406

  14. ABC relaxation theory and the factor structure of relaxation states, recalled relaxation activities, dispositions, and motivations.

    PubMed

    Smith, J C; Wedell, A B; Kolotylo, C J; Lewis, J E; Byers, K Y; Segin, C M

    2000-06-01

    ABC Relaxation Theory proposes 15 psychological relaxation-related states (R-States): Sleepiness, Disengagement, Physical Relaxation, Mental Quiet, Rested/Refreshed, At Ease/At Peace, Energized, Aware, Joy, Thankfulness and Love, Prayerfulness, Childlike Innocence, Awe and Wonder, Mystery, and Timeless/Boundless/Infinite. The present study summarizes the results of 13 separate factor analyses of immediate relaxation-related states, states associated with recalled relaxation activities, relaxation dispositions, and relaxation motivations on a combined sample of 1,904 individuals (group average ages ranged from 28-40 yr.). Four exploratory factor analyses of Smith Relaxation Inventories yielded 15 items that most consistently and exclusively load (generally at least .70) on six replicated factors. These items included happy, joyful, energized, rested, at peace, warm, limp, silent, quiet, dozing, drowsy, prayerful, mystery, distant, and indifferent. Subsequent factor analyses restricted to these items and specifying six factors were performed on 13 different data sets. Each yielded the same six-factor solution: Factor 1: Centered Positive Affect, Factor 2: Sleepiness, Factor 3: Disengagement, Factor 4: Physical Relaxation, Factor 5: Mental Quiet, and Factor 6: Spiritual. Implications for ABC Relaxation Theory are discussed.

  15. Peripheral brain-derived neurotrophic factor is related to cardiovascular risk factors in active and inactive elderly men

    PubMed Central

    Zembron-Lacny, A.; Dziubek, W.; Rynkiewicz, M.; Morawin, B.; Woźniewski, M.

    2016-01-01

    Regular exercise plays an important preventive and therapeutic role in heart and vascular diseases, and beneficially affects brain function. In blood, the effects of exercise appear to be very complex and could include protection of vascular endothelial cells via neurotrophic factors and decreased oxidative stress. The purpose of this study was to identify the age-related changes in peripheral brain-derived neurotrophic factor (BDNF) and its relationship to oxidative damage and conventional cardiovascular disease (CVD) biomarkers, such as atherogenic index, C-reactive protein (hsCRP) and oxidized LDL (oxLDL), in active and inactive men. Seventeen elderly males (61-80 years) and 17 young males (20-24 years) participated in this study. According to the 6-min Åstrand-Rhyming bike test, the subjects were classified into active and inactive groups. The young and elderly active men had a significantly better lipoprotein profile and antioxidant status, as well as reduced oxidative damage and inflammatory state. The active young and elderly men had significantly higher plasma BDNF levels compared to their inactive peers. BDNF was correlated with VO2max (r=0.765, P<0.001). In addition, we observed a significant inverse correlation of BDNF with atherogenic index (TC/HDL), hsCRP and oxLDL. The findings demonstrate that a high level of cardiorespiratory fitness reflected in VO2max was associated with a higher level of circulating BDNF, which in turn was related to common CVD risk factors and oxidative damage markers in young and elderly men. PMID:27332774

  16. Comparing citrated native, kaolin-activated, and tissue factor-activated samples and determining intraindividual variability for feline thromboelastography.

    PubMed

    Banerjee, Amrita; Blois, Shauna L; Wood, R Darren

    2011-11-01

    Thromboelastography (TEG) is a point-of-care whole blood test of hemostasis. While TEG is becoming more widely used in veterinary medicine, few studies describe the use of TEG in cats. The objectives of the current study were to: 1) document the range of TEG variables produced in healthy cats using 3 sample types (citrated native, kaolin-activated, and tissue factor-activated), and 2) determine if there was a significant difference between 2 separate samples obtained from individual healthy cats on the same day. Jugular venipuncture was performed in 20 cats, and citrated blood collected for TEG. TEG analysis was performed on citrated native, kaolin-activated, and tissue factor-activated blood for each sample. Two hours later, the procedure was repeated from the opposite jugular vein, yielding a total of 120 analyses. Reaction time (R), alpha angle (α), kappa value (κ), and maximum amplitude (MA) were recorded from each tracing. No significant differences were found between TEG tracings from the first and second venipuncture samples. Significant differences were found between sample types for R, α, κ, and MA. Means for citrated native/kaolin-activated/tissue factor-activated methods were R = 4.1/3.7/0.6 min; κ = 2.5/1.8/2.2 min; α = 59.9/65.1/70.4 degrees; MA = 47.4/49.9/44.7 mm. A limitation of this study was the small number of cats used. Thromboelastography analysis may be a suitable method of evaluating hemostasis in cats.

  17. Exploring Socio-Ecological Factors Influencing Active and Inactive Spanish Students in Years 12 and 13

    ERIC Educational Resources Information Center

    Devís-Devís, José; Beltrán-Carrillo, Vicente J.; Peiró-Velert, Carmen

    2015-01-01

    This paper explores socio-ecological factors and their interplay that emerge from a qualitative study and influence adolescents' physical activity and sport participation. A total of 13 boys and 7 girls active and inactive adolescents, from years 12 and 13 and different types of school (state and private), participated in semi-structured…

  18. Testing the Youth Physical Activity Promotion Model: Fatness and Fitness as Enabling Factors

    ERIC Educational Resources Information Center

    Chen, Senlin; Welk, Gregory J.; Joens-Matre, Roxane R.

    2014-01-01

    As the prevalence of childhood obesity increases, it is important to examine possible differences in psychosocial correlates of physical activity between normal weight and overweight children. The study examined fatness (weight status) and (aerobic) fitness as Enabling factors related to youth physical activity within the Youth Physical Activity…

  19. Associations of Weight Status, Social Factors, and Active Travel among College Students

    ERIC Educational Resources Information Center

    Bopp, Melissa; Behrens, Timothy K.; Velecina, Rachel

    2014-01-01

    Background: Active travel (AT) is associated with various health benefits and may help prevent the decline in physical activity during college years. Purpose: The purpose of this study was to examine the relationship of several factors with AT to campus by weight status. Methods: Students at a large northeastern US campus completed an online…

  20. Factors Associated with Sexual Activity among High-School Students in Nairobi, Kenya

    ERIC Educational Resources Information Center

    Kabiru, Caroline W.; Orpinas, Pamela

    2009-01-01

    The high level of HIV infection in sub-Saharan Africa has led to an increased interest in understanding the determinants of sexual activity among young people, who are at high risk of sexually transmitted infections. The present study examined sociodemographic, behavioral, and psychosocial factors associated with heterosexual activity among a…

  1. Factors that Limit and Enable Preschool-Aged Children's Physical Activity on Child Care Centre Playgrounds

    ERIC Educational Resources Information Center

    Coleman, Bianca; Dyment, Janet E.

    2013-01-01

    The incidence of childhood obesity amongst preschool-aged children has increased dramatically in recent years and can be attributed, in part, to a lack of physical activity amongst children in this age group. This study explores the social factors that stand to limit and/or enable children's physical activity opportunities in outdoor settings in…

  2. Association between Social and Environmental Factors and Physical Activity Opportunities in Middle Schools

    ERIC Educational Resources Information Center

    Xu, Furong; Chepyator-Thomson, Jepkorir; Liu, Wenhao; Schmidlein, Robert

    2010-01-01

    School-based physical activity (PA) interventions impact children's PA involvement and thus opportunities and associated factors for the promotion of physical activity in children need to be examined. The purpose of this study was to examine physical education teachers' perceptions of PA opportunities available to students at the middle school…

  3. Interpersonal and Intrapersonal Factors Associated with Autonomous Motivation in Adolescents' After-School Activities

    ERIC Educational Resources Information Center

    Beiswenger, Krista L.; Grolnick, Wendy S.

    2010-01-01

    This study explored interpersonal and intrapersonal factors associated with the level of autonomous motivation adolescents experience for their after-school activities. A total of 142 seventh-grade adolescents completed measures of peer relatedness, autonomy within friendships, mother and father autonomy support, perceived activity competence,…

  4. Stress-Activated Cap’n’collar Transcription Factors in Aging and Human Disease

    PubMed Central

    Sykiotis, Gerasimos P.; Bohmann, Dirk

    2010-01-01

    Cap’n’collar (Cnc) transcription factors are conserved in metazoans and have important developmental and homeostatic functions. The vertebrate Nrf1, Nrf2, and Nrf3, the Caenorhabditis elegans SKN-1, and the Drosophila CncC comprise a subgroup of Cnc factors that mediate adaptive responses to cellular stress. The most studied stress-activated Cnc factor is Nrf2, which orchestrates the transcriptional response of cells to oxidative stressors and electrophilic xenobiotics. In rodent models, signaling by Nrf2 defends against oxidative stress and aging-associated disorders, such as neurodegeneration, respiratory diseases, and cancer. In humans, polymorphisms that decrease Nrf2 abundance have been associated with various pathologies of the skin, respiratory system, and digestive tract. In addition to preventing disease in rodents and humans, Cnc factors have lifespan-extending and anti-aging functions in invertebrates. However, despite the pro-longevity and antioxidant roles of stress-activated Cnc factors, their activity paradoxically declines in aging model organisms and in humans suffering from progressing respiratory disease or neurodegeneration. We review the roles and regulation of stress-activated Cnc factors across species, present all reported instances in which their activity is paradoxically decreased in aging and disease, and discuss the possibility that the pharmacological restoration of Nrf2 signaling may be useful in the prevention and treatment of age-related diseases. PMID:20215646

  5. Factors that influence physical activity for pregnant and postpartum women and implications for primary care.

    PubMed

    Doran, Frances; Davis, Kierrynn

    2011-01-01

    Many pregnant women and women of child-bearing age do not engage in the recommended levels of physical activity despite the well known benefits. Pregnancy and the postpartum period can be a time when inactivity actually increases. Women who experience gestational diabetes mellitus (GDM) during their pregnancy are often advised to become more active in order to ameliorate their increased risk of developing type 2 diabetes. Health professionals have an influential role in promoting physical activity, which would be enhanced with an understanding of the factors that positively and negatively influence women's participation in physical activity during pregnancy and in the postpartum period. This research sought to explore these factors with pregnant and postpartum women including those who had experienced GDM and the attention given to physical activity during pregnancy. A survey was developed after a critical review of factors identified from previous studies. Women were recruited from the antenatal clinic, community health centres and the local media. Results from 72 women are reported from a predominately well educated, Caucasian population. Overall, the results were confirmatory of factors previously identified. Lack of child care, time constraints, no time and feeling unwell during pregnancy hindered activity and factors that facilitated activity included family support, enjoyment of activity and to prevent later health problems. It was also found that non-GDM women are given minimal advice about exercise during pregnancy. A checklist has been developed for health professionals, in partnership with women, to direct attention to the factors that enable and hinder participation in physical activity during and after pregnancy.

  6. Overexpression and activation of hepatocyte growth factor/scatter factor in human non-small-cell lung carcinomas.

    PubMed Central

    Olivero, M.; Rizzo, M.; Madeddu, R.; Casadio, C.; Pennacchietti, S.; Nicotra, M. R.; Prat, M.; Maggi, G.; Arena, N.; Natali, P. G.; Comoglio, P. M.; Di Renzo, M. F.

    1996-01-01

    Hepatocyte growth factor/scatter factor (HGF/SF) stimulates the invasive growth of epithelial cells via the c-MET oncogene-encoded receptor. In normal lung, both the receptor and the ligand are detected, and the latter is known to be a mitogenic and a motogenic factor for both cultured bronchial epithelial cells and non-small-cell carcinoma lines. Here, ligand and receptor expression was examined in 42 samples of primary human non-small-cell lung carcinoma of different histotype. Each carcinoma sample was compared with adjacent normal lung tissue. The Met/HGF receptor was found to be 2 to 10-fold increased in 25% of carcinoma samples (P = 0.0113). The ligand, HGF/SF, was found to be 10 to 100-fold overexpressed in carcinoma samples (P < 0.0001). Notably, while HGF/SF was occasionally detectable and found exclusively as a single-chain inactive precursor in normal tissues, it was constantly in the biologically-active heterodimeric form in carcinomas. Immunohistochemical staining showed homogeneous expression of both the receptor and the ligand in carcinoma samples, whereas staining was barely detectable in their normal counterparts. These data show that HGF/SF is overexpressed and consistently activated in non-small-cell lung carcinomas and may contribute to the invasive growth of lung cancer. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 PMID:8980383

  7. Arabidopsis Sigma Factor Binding Proteins Are Activators of the WRKY33 Transcription Factor in Plant Defense[W

    PubMed Central

    Lai, Zhibing; Li, Ying; Wang, Fei; Cheng, Yuan; Fan, Baofang; Yu, Jing-Quan; Chen, Zhixiang

    2011-01-01

    Necrotrophic pathogens are important plant pathogens that cause many devastating plant diseases. Despite their impact, our understanding of the plant defense response to necrotrophic pathogens is limited. The WRKY33 transcription factor is important for plant resistance to necrotrophic pathogens; therefore, elucidation of its functions will enhance our understanding of plant immunity to necrotrophic pathogens. Here, we report the identification of two WRKY33-interacting proteins, nuclear-encoded SIGMA FACTOR BINDING PROTEIN1 (SIB1) and SIB2, which also interact with plastid-encoded plastid RNA polymerase SIGMA FACTOR1. Both SIB1 and SIB2 contain an N-terminal chloroplast targeting signal and a putative nuclear localization signal, suggesting that they are dual targeted. Bimolecular fluorescence complementation indicates that WRKY33 interacts with SIBs in the nucleus of plant cells. Both SIB1 and SIB2 contain a short VQ motif that is important for interaction with WRKY33. The two VQ motif–containing proteins recognize the C-terminal WRKY domain and stimulate the DNA binding activity of WRKY33. Like WRKY33, both SIB1 and SIB2 are rapidly and strongly induced by the necrotrophic pathogen Botrytis cinerea. Resistance to B. cinerea is compromised in the sib1 and sib2 mutants but enhanced in SIB1-overexpressing transgenic plants. These results suggest that dual-targeted SIB1 and SIB2 function as activators of WRKY33 in plant defense against necrotrophic pathogens. PMID:21990940

  8. Nitric oxide mediates angiogenesis induced in vivo by platelet-activating factor and tumor necrosis factor-alpha.

    PubMed Central

    Montrucchio, G.; Lupia, E.; de Martino, A.; Battaglia, E.; Arese, M.; Tizzani, A.; Bussolino, F.; Camussi, G.

    1997-01-01

    We evaluated the role of an endogenous production of nitric oxide (NO) in the in vitro migration of endothelial cells and in the in vivo angiogenic response elicited by platelet-activating factor (PAF), tumor necrosis factor-alpha (TNF), and basic fibroblast growth factor (bFGF). The NO synthase inhibitor, N omega-nitro-L-arginine-methyl ester (L-NAME), but not its enantiomer D-NAME, prevented chemotaxis of endothelial cells induced in vitro by PAF and by TNF. The motogenic activity of TNF was also inhibited by WEB 2170, a specific PAF-receptor antagonist. In contrast, chemotaxis induced by bFGF was not prevented by L-NAME or by WEB 2170. Angiogenesis was studied in vivo in a murine model in which Matrigel was used as a vehicle for the delivery of mediators. In this model, the angiogenesis induced by PAF and TNF was inhibited by WEB 2170 and L-NAME but not by D-NAME. In contrast, angiogenesis induced by bFGF was not affected by L-NAME or by WEB 2170. TNF, but not bFGF, induced PAF synthesis within Matrigel. These results suggest that NO mediates the angiogenesis induced by PAF as well as that induced by TNF, which is dependent on the production of PAF. In contrast, the angiogenic effect of bFGF appears to be both PAF and NO independent. Images Figure 3 Figure 4 PMID:9250168

  9. Tissue Factor Activity in Lymphocyte Cultures from Normal Individuals and Patients with Hemophilia A

    PubMed Central

    Rickles, Frederick R.; Hardin, John A.; Pitlick, Frances A.; Hoyer, Leon W.; Conrad, Marcel E.

    1973-01-01

    The procoagulant material of lymphocytes has been characterized as tissue factor. Lymphocytes stimulated with phytohemagglutinin or the purified protein derivative of the tubercle bacillus developed procoagulant activity with incubation in tissue culture. While this material corrected the prolonged clotting time of factor VIII (AHF) deficient plasma, we have shown, utilizing a sensitive radioimmunoassay, that no AHF antigen was present in the cell cultures. Further, we have demonstrated this material to be tissue factor by coagulation techniques and immunological cross-reactivity. The published data regarding factor VIII synthesis is reviewed in light of these observations and comments are made regarding the role of the lymphocyte procoagulant. PMID:4634046

  10. Thrombin generation by activated factor VII on platelet activated by different agonists. Extending the cell-based model of hemostasis

    PubMed Central

    Altman, Raul; Scazziota, Alejandra Silvia; Herrera, Maria de Lourdes; Gonzalez, Claudio

    2006-01-01

    Background Platelet activation is crucial in normal hemostasis. Using a clotting system free of external tissue factor, we investigated whether activated Factor VII in combination with platelet agonists increased thrombin generation (TG) in vitro. Methods and results TG was quantified by time parameters: lag time (LT) and time to peak (TTP), and by amount of TG: peak of TG (PTG) and area under thrombin formation curve after 35 minutes (AUC→35min) in plasma from 29 healthy volunteers using the calibrated automated thrombography (CAT) technique. TG parameters were measured at basal conditions and after platelet stimulation by sodium arachidonate (AA), ADP, and collagen (Col). In addition, the effects of recombinant activated FVII (rFVIIa) alone or combined with the other platelet agonists on TG parameters were investigated. We found that LT and TTP were significantly decreased (p < 0.05) and PTG and AUC→35min were significantly increased (p < 0.05) in platelet rich plasma activated with AA, ADP, Col, and rFVIIa compared to non-activated platelet rich plasma from normal subjects (p = 0.01). Furthermore platelet rich plasma activated by the combined effects of rFVIIa plus AA, ADP or Col had significantly reduced LT and TTP and increased AUC→35min (but not PTG) when compared to platelet rich plasma activated with agonists in the absence of rFVIIa. Conclusion Platelets activated by AA, ADP, Col or rFVIIa triggered TG. This effect was increased by combining rFVIIa with other agonists. Our intrinsic coagulation system produced a burst in TG independent of external tissue factor activity an apparent hemostatic effect with little thrombotic capacity. Thus we suggest a modification in the cell-based model of hemostasis. PMID:16630353

  11. Factor Xa stimulates fibroblast procollagen production, proliferation, and calcium signaling via PAR{sub 1} activation

    SciTech Connect

    Blanc-Brude, Olivier P. . E-mail: olivier.blanc-brude@larib.inserm.fr; Archer, Fabienne; Leoni, Patricia; Derian, Claudia; Bolsover, Steven; Laurent, Geoffrey J.; Chambers, Rachel C.

    2005-03-10

    Fibroblast proliferation and procollagen production are central features of tissue repair and fibrosis. In addition to its role in blood clotting, the coagulation cascade proteinase thrombin can contribute to tissue repair by stimulating fibroblasts via proteolytic activation of proteinase-activated receptor-1 (PAR{sub 1}). During hemostasis, the coagulation cascade proteinase factor X is converted into factor Xa. We have previously shown that factor Xa upregulates fibroblast proliferation via production of autocrine PDGF. In this study, we further examined the effects of factor Xa on fibroblast function and aimed to identify its signaling receptor. We showed that factor Xa stimulates procollagen promoter activity and protein production by human and mouse fibroblasts. This effect was independent of PDGF and thrombin production, but dependent on factor Xa proteolytic activity. We also showed that PAR{sub 1}-deficient mouse fibroblasts did not upregulate procollagen production, mobilize cytosolic calcium, or proliferate in response to factor Xa. Desensitization techniques and PAR{sub 1}-specific agonists and inhibitors were used to demonstrate that PAR{sub 1} mediates factor Xa signaling in human fibroblasts. This is the first report that factor Xa stimulates extracellular matrix production. In contrast with endothelial cells and vascular smooth muscle cells, fibroblasts appear to be the only cell type in which the effects of factor Xa are mediated mainly via PAR{sub 1} and not PAR{sub 2}. These findings are critical for our understanding of tissue repair and fibrotic mechanisms, and for the design of novel approaches to inhibit the profibrotic effects of the coagulation cascade without compromising blood hemostasis.

  12. Agreement between two cutoff points for physical activity and associated factors in young individuals☆

    PubMed Central

    Coledam, Diogo Henrique Constantino; Ferraiol, Philippe Fanelli; Pires, Raymundo; Ribeiro, Edinéia Aparecida Gomes; Ferreira, Marco Antonio Cabral; de Oliveira, Arli Ramos

    2014-01-01

    Objective: To analyze the agreement between two cutoff points for physical activity (300 and 420 minutes/week) and associated factors in youth. Methods: The study enrolled 738 adolescents of Londrina city, Paraná, Southern Brazil. The following variables were collected by a self report questionnaire: presence of moderate to vigorous physical activity, gender, age, father and mother education level, with whom the adolescent lives, number of siblings, physical activity perception, participation in Physical Education classes, facilities available to physical activity practice and sedentary behavior. Prevalence of physical activity between criterions were compared using McNemar test and the agreement was analysed by Kappa index. Multivariate analysis was performed using Poisson regression with robust variance adjustment was applied. Results: The prevalence for physical activity was significantly different: 22,3% for 300 minutes/week and 12,8% for 420 minutes/week (p<0,05), but the agreement was strong (k=0,82, p<0,001). The variables gender, father education, physical activity perception and sedentary behavior were associated to physical activity in both analyzed criteria. Participation in Physical Education class and facilities available to physical activity practice were associated to physical activity only with 300 minutes/week cutoff point. Conclusion: Caution is suggested regarding cutoffs use for physical activity in epidemiological studies, considering they can result in differences in prevalence of physical activity and its associated factors. PMID:25479852

  13. Physical activity level and related factors in adolescents with cerebral palsy.

    PubMed

    van Eck, Mirjam; Dallmeijer, Annet J; Beckerman, Heleen; van den Hoven, Petronella A M; Voorman, Jeanine M; Becher, Jules G

    2008-02-01

    The purpose of this study was to describe the physical activity level of adolescents with cerebral palsy (CP) and to investigate the associated factors. The physical activity level was measured by means of a questionnaire filled in by the parents of 72 adolescents with CP (12-16 years of age) and expressed in METs. Older age, female gender, and hip dysplasia were significantly associated with a lower level of physical activity. Eighty-nine percent were not physically active enough according to the Dutch norm. Physical activity needs to be promoted, especially among older adolescents with CP (age 14-16 years), girls, and adolescents with hip dysplasia.

  14. Reactive Oxygen Species and Nuclear Factor Erythroid 2-Related Factor 2 Activation in Diabetic Nephropathy: A Hidden Target

    PubMed Central

    Abdo, Shaaban; Zhang, Shao-Ling; Chan, John S.D.

    2015-01-01

    Hyperglycemia, oxidative stress and renin-angiotensin system (RAS) dysfunction have been implicated in diabetic nephropathy (DN) progression, but the underlying molecular mechanisms are far from being fully understood. In addition to the systemic RAS, the existence of a local intrarenal RAS in renal proximal tubular cells has been recognized. Angiotensinogen is the sole precursor of all angiotensins (Ang). Intrarenal reactive oxygen species (ROS) generation, Ang II level and RAS gene expression are up-regulated in diabetes, indicating that intrarenal ROS and RAS activation play an important role in DN. The nuclear factor erythroid 2-related factor 2 (Nrf2)-Kelch-like ECH-associated protein 1 (Keap1) pathway is one of the major protective processes that occurs in response to intracellular oxidative stress. Nrf2 stimulates an array of antioxidant enzymes that convert excessive ROS to less reactive or less damaging forms. Recent studies have, however, revealed that Nrf2 activation might have other undesirable effects in diabetic animals and in diabetic patients with chronic kidney disease. This mini-review summarizes current knowledge of the relationship between ROS, Nrf2 and intra renal RAS activation in DN progression as well as possible novel target(s) for DN treatment. PMID:26213634

  15. The secret struggle of the active girl: a qualitative synthesis of interpersonal factors that influence physical activity in adolescent girls.

    PubMed

    Standiford, Anne

    2013-10-01

    The author conducted a systematic review of 19 international, multidisciplinary, qualitative studies of interpersonal factors that influence physical activity in adolescent girls. Themes were deductively generated based on reported findings, and were organized according to frequency of occurrence. Themes were further organized according to a theoretical model to illustrate how interpersonal, perceptual, and situational influences affect physical activity in adolescent girls. The three most frequently discovered themes follow: (a) ability comparison and competition; (b) family, peer, and teacher influence; and (c) appearance concerns. It is important to consider the influence of gender role conflict on physical activity.

  16. The translation initiation factor 3f (eIF3f) exhibits a deubiquitinase activity regulating Notch activation.

    PubMed

    Moretti, Julien; Chastagner, Patricia; Gastaldello, Stefano; Heuss, Sara F; Dirac, Annette M; Bernards, René; Masucci, Maria G; Israël, Alain; Brou, Christel

    2010-11-23

    Activation of the mammalian Notch receptor after ligand binding relies on a succession of events including metalloprotease-cleavage, endocytosis, monoubiquitination, and eventually processing by the gamma-secretase, giving rise to a soluble, transcriptionally active molecule. The Notch1 receptor was proposed to be monoubiquitinated before its gamma-secretase cleavage; the targeted lysine has been localized to its submembrane domain. Investigating how this step might be regulated by a deubiquitinase (DUB) activity will provide new insight for understanding Notch receptor activation and downstream signaling. An immunofluorescence-based screening of an shRNA library allowed us to identify eIF3f, previously known as one of the subunits of the translation initiation factor eIF3, as a DUB targeting the activated Notch receptor. We show that eIF3f has an intrinsic DUB activity. Knocking down eIF3f leads to an accumulation of monoubiquitinated forms of activated Notch, an effect counteracted by murine WT eIF3f but not by a catalytically inactive mutant. We also show that eIF3f is recruited to activated Notch on endocytic vesicles by the putative E3 ubiquitin ligase Deltex1, which serves as a bridging factor. Finally, catalytically inactive forms of eIF3f as well as shRNAs targeting eIF3f repress Notch activation in a coculture assay, showing that eIF3f is a new positive regulator of the Notch pathway. Our results support two new and provocative conclusions: (1) The activated form of Notch needs to be deubiquitinated before being processed by the gamma-secretase activity and entering the nucleus, where it fulfills its transcriptional function. (2) The enzyme accounting for this deubiquitinase activity is eIF3f, known so far as a translation initiation factor. These data improve our knowledge of Notch signaling but also open new avenues of research on the Zomes family and the translation initiation factors.

  17. A comparison between recombinant activated factor VII (Aryoseven) and Novoseven in patients with congenital factor VII deficiency.

    PubMed

    Faranoush, M; Abolghasemi, Hassan; Toogeh, Gh; Karimi, M; Eshghi, P; Managhchi, M; Hoorfar, H; Dehdezi, B Keikhaei; Mehrvar, A; Khoeiny, B; Kamyar, K; Heshmat, R; Baghaeipour, M R; Mirbehbahani, N B; Fayazfar, R; Ahmadinejad, M; Naderi, M

    2015-11-01

    In order to establish the efficacy and biosimilar nature of AryoSeven to NovoSeven in the treatment of congenital factor VII (FVII) deficiency, patients received either agent at 30 μg/kg, intravenously per week for 4 weeks, in a randomized fashion. The primary aim was to compare FVII:coagulation activity (FVII:C), 20 minutes after recombinant activated FVII (rFVIIa) injection, in the 2 groups. A secondary measure was self-reported bleeding. The median interquartile baseline range of the plasma level of activated FVII (FVIIa) activity in the 2 groups was 1.6 (1.1-14.0) IU/dL and 5.0 (1.1-25.5) IU/dL. All patients achieved levels of FVIIa (FVII:C) >30 IU/dL, 20 minutes after the injection of rFVIIa. Bleeding was similar between the 2 groups, with a comparable decrease in severity and frequency compared to the last month prior to treatment. AryoSeven is similar to NovoSeven in increasing postinjection FVIIa activity as well as in clinical safety and efficacy.

  18. Gastrointestinal growth factors and hormones have divergent effects on Akt activation

    PubMed Central

    Berna, Marc J.; Tapia, Jose A.; Sancho, Veronica; Thill, Michelle; Pace, Andrea; Hoffmann, K. Martin; Gonzalez-Fernandez, Lauro; Jensen, Robert T.

    2009-01-01

    Akt is a central regulator of apoptosis, cell growth and survival. Growth factors and some G-protein-coupled receptors (GPCR) regulate Akt. Whereas growth-factor activation of Akt has been extensively studied, the regulation of Akt by GPCR's, especially gastrointestinal hormones/neurotransmitters, remains unclear. To address this area, in this study the effects of GI growth factors and hormones/neurotransmitters were investigate in rat pancreatic acinar cells which are high responsive to these agents. Pancreatic acini expressed Akt and 5 of 7 known pancreatic growth-factors stimulate Akt phosphorylation (T308, S473) and translocation. These effects are mediated by p85 phosphorylation and activation of PI3K. GI hormones increasing intracellular cAMP had similar effects. However, GI-hormones/neurotransmitters[CCK, bombesin,carbachol] activating phospholipase C (PLC) inhibited basal and growth-factor-stimulated Akt activation. Detailed studies with CCK, which has both physiological and pathophysiological effects on pancreatic acinar cells at different concentrations, demonstrated CCK has a biphasic effect: at low concentrations(pM) stimulating Akt by a Src-dependent mechanism and at higher concentrations(nM) inhibited basal and stimulated Akt translocation, phosphorylation and activation, by de-phosphorylating p85 resulting in decreasing PI3K activity. This effect required activation of both limbs of the PLC-pathway and a protein tyrosine phosphatase, but was not mediated by p44/42 MAPK, Src or activation of a serine phosphatase. Akt inhibition by CCK was also found in vivo and in Panc-1 cancer cells where it inhibited serum-mediated rescue from apoptosis. These results demonstrate that GI growth factors as well as gastrointestinal hormones/neurotransmitters with different cellular basis of action can all regulate Akt phosphorylation in pancreatic acinar cells. This regulation is complex with phospholipase C agents such as CCK, because both stimulatory and inhibitory

  19. Activation of the serum response factor by p65/NF-kappaB.

    PubMed Central

    Franzoso, G; Carlson, L; Brown, K; Daucher, M B; Bressler, P; Siebenlist, U

    1996-01-01

    This study demonstrates that the NF-kappaB subunit p65 can act like an accessory protein for the serum response factor (SRF) in transfection assays. p65 functionally synergizes with SRF to activate the transcription of a reporter construct dependent only on the serum response element (SRE). The synergy of the two factors requires neither a kappaB motif nor direct contact of p65 with DNA. Consistent with these results, a physical complex containing p65 and SRF is observed in vitro. Synergy of the factors is independent of the previously described activation domains present on p65, ruling out indirect effects of p65, but synergy is dependent on the activation domain of SRF. The complexing of p65 and SRF is mediated by a segment of the SRF DNA binding domain, a region of the protein which has also been reported to inhibit its own activation domain. We speculate that p65, upon direct or facilitated interaction with SRF, may relieve the inhibitory activity of this segment, thus enabling the activation domain of SRF to become fully functional. In contrast to p65, the p50 subunit of NF-kappaB does not interact significantly with SRF, either functionally or physically. The data suggest the intriguing possibility that NF-kappaB may participate in the regulation of SRE-dependent promoters, expanding the range of activities of this rapidly activatable transcription factor. Images PMID:8670842

  20. Female reproductive factors are associated with objectively measured physical activity in middle-aged women

    PubMed Central

    Kulmala, Janne; Aukee, Pauliina; Hakonen, Harto; Kujala, Urho M.; Lowe, Dawn A.; Kovanen, Vuokko; Tammelin, Tuija; Sipilä, Sarianna

    2017-01-01

    Physical activity improves health and may delay the onset of several chronic diseases. For women in particular, the rate of these diseases accelerates at middle age; therefore it is important to identify the determinants of health-enhancing physical activity during midlife in this population. In this study, we focused on determinants that are unique to the female sex, such as childbearing and menopause. The main objective was to characterize the level of physical activity and differences between active and inactive middle-aged Finnish women. In addition, we examined the association of physical activity with female reproductive factors at midlife. The study population consisted of 647 women aged 48 to 55 years who participated in our Estrogenic Regulation of Muscle Apoptosis (ERMA) study during the period from 2015 to 2016. Physical activity was measured objectively using hip-worn accelerometers for seven consecutive days. The outcome measures included the amounts of light intensity physical activity and moderate to vigorous intensity physical activity accumulated in bouts of at least 10 minutes (MVPA10). MVPA10 was used to determine whether women were placed in the active (≥150 min/week) or inactive (<150 min/week) group. Multiple linear regression models were performed with physical activity measures as dependent variables and cumulative reproductive history index, menopausal symptoms, and pelvic floor dysfunction as independent variables. We found that a large portion (61%) of Finnish middle-aged women did not meet the physical activity recommendations of 150 minutes of MVPA10 per week. In the studied cohort, 78% of women experienced menopausal symptoms, and 54% exhibited pelvic floor dysfunction. Perceived menopausal symptoms were associated with greater light physical activity. Perceived pelvic floor dysfunction was associated with lower MVPA10. According to the fully adjusted multiple linear regression models, reproductive factors explained 6.0% of the

  1. Activation of Rho GTPases by Cytotoxic Necrotizing Factor 1 Induces Macropinocytosis and Scavenging Activity in Epithelial Cells

    PubMed Central

    Fiorentini, Carla; Falzano, Loredana; Fabbri, Alessia; Stringaro, Annarita; Logozzi, Mariaantonia; Travaglione, Sara; Contamin, Stéphanette; Arancia, Giuseppe; Malorni, Walter; Fais, Stefano

    2001-01-01

    Macropinocytosis, a ruffling-driven process that allows the capture of large material, is an essential aspect of normal cell function. It can be either constitutive, as in professional phagocytes where it ends with the digestion of captured material, or induced, as in epithelial cells stimulated by growth factors. In this case, the internalized material recycles back to the cell surface. We herein show that activation of Rho GTPases by a bacterial protein toxin, the Escherichia coli cytotoxic necrotizing factor 1 (CNF1), allowed epithelial cells to engulf and digest apoptotic cells in a manner similar to that of professional phagocytes. In particular, we have demonstrated that 1) the activation of all Rho, Rac, and Cdc42 by CNF1 was essential for the capture and internalization of apoptotic cells; and 2) such activation allowed the discharge of macropinosomal content into Rab7 and lysosomal associated membrane protein-1 acidic lysosomal vesicles where the ingested particles underwent degradation. Taken together, these findings indicate that CNF1-induced “switching on” of Rho GTPases may induce in epithelial cells a scavenging activity, comparable to that exerted by professional phagocytes. The activation of such activity in epithelial cells may be relevant, in mucosal tissues, in supporting or integrating the scavenging activity of resident macrophages. PMID:11452003

  2. Using avian radar to examine relationships among avian activity, bird strikes, and meteorological factors

    USGS Publications Warehouse

    Coates, Peter S.; Casazza, Michael L.; Halstead, Brian J.; Fleskes, Joseph P.; Laughlin, James A.

    2011-01-01

    Radar systems designed to detect avian activity at airfields are useful in understanding factors that influence the risk of bird and aircraft collisions (bird strikes). We used an avian radar system to measure avian activity at Beale Air Force Base, California, USA, during 2008 and 2009. We conducted a 2-part analysis to examine relationships among avian activity, bird strikes, and meteorological and time-dependent factors. We found that avian activity around the airfield was greater at times when bird strikes occurred than on average using a permutation resampling technique. Second, we developed generalized linear mixed models of an avian activity index (AAI). Variation in AAI was first explained by seasons that were based on average migration dates of birds at the study area. We then modeled AAI by those seasons to further explain variation by meteorological factors and daily light levels within a 24-hour period. In general, avian activity increased with decreased temperature, wind, visibility, precipitation, and increased humidity and cloud cover. These effects differed by season. For example, during the spring bird migration period, most avian activity occurred before sunrise at twilight hours on clear days with low winds, whereas during fall migration, substantial activity occurred after sunrise, and birds generally were more active at lower temperatures. We report parameter estimates (i.e., constants and coefficients) averaged across models and a relatively simple calculation for safety officers and wildlife managers to predict AAI and the relative risk of bird strike based on time, date, and meteorological values. We validated model predictability and assessed model fit. These analyses will be useful for general inference of avian activity and risk assessment efforts. Further investigation and ongoing data collection will refine these inference models and improve our understanding of factors that influence avian activity, which is necessary to inform

  3. Transcription factor activation following exposure of an intact lung preparation to metallic particulate matter.

    PubMed Central

    Samet, James M; Silbajoris, Robert; Huang, Tony; Jaspers, Ilona

    2002-01-01

    Metallic constituents contained in ambient particulate matter have been associated with adverse effects in a number of epidemiologic, in vitro, and in vivo studies. Residual oil fly ash (ROFA) is a metallic by-product of the combustion of fossil fuel oil, which has been shown to induce a variety of proinflammatory responses in lung cells. We have examined signaling pathways activated in response to ROFA exposure and recently reported that ROFA treatment activates multiple mitogen-activated protein (MAP) kinases in the rat lung. In the present study we extended our investigations on the mechanism of toxicity of ROFA to include transcription factors whose activities are regulated by MAP kinases as well as possible effectors of transcriptional changes that mediate the effects of ROFA. We applied immunohistochemical methods to detect ROFA-induced activation of nuclear factor-kappa B (NF kappa B), activating transcription factor-2 (ATF-2), c-Jun, and cAMP response element binding protein (CREB) in intact lung tissue and confirmed and characterized their functional activation using DNA binding assays. We performed these studies using a perfused rabbit lung model that is devoid of blood elements in order to distinguish between intrinsic lung cell effects and effects that are secondary to inflammatory cell influx. We report here that exposure to ROFA results in a rapid activation of all of the transcription factors studied by exerting direct effects on lung cells. These findings validate the use of immunohistochemistry to detect transcription factor activation in vivo and demonstrate the utility of studying signaling changes in response to environmental exposures. PMID:12361922

  4. Effect of some factors used to the chicken meat preservation and processing on the protease activity.

    PubMed

    Przysiezna, E; Skrabka-Blotnicka, T

    1996-08-01

    The obtained results indicated that the cathepsin activity was higher by about 60% in the extract from thigh than from breast muscles. Freezing and defrosting (not stored) of chicken meat did not influence the breast muscle cathepsin activity while they caused a decrease of activity of about 20% in the case of thigh muscles. The increase in cathepsin activity was noticed in both kinds of muscles during storage at -20 degrees C up to 4 months (45.6% and 19.4% for thigh and breast muscles respectively). The activity of cathepsin in extract from 5 months stored meat reached 80% in case of breast muscles and 83% in case of thigh muscles in relation to control sample respectively. The cathepsin activity significantly increased during heating of breast muscles up to 60 degrees C, but in case of thigh muscles it was slightly higher than at 50 degrees C. The heating of cured chicken breast muscles up to 60 degrees C caused a non significant growth in cathepsin activity opposite to raw muscles. The cathepsin activity from all cured samples heated up to 70 degrees C were several times lower in relation to control samples. The cathepsin activity of both thigh and breast muscles were resistant to gamma radiation. The investigated factors caused changes in the activity of cathepsin but none of them caused its total inactivation. The changes of cathepsin activity depended on the kind of muscles and the kind and the value of acting factors.

  5. Muscle Atrophy Reversed by Growth Factor Activation of Satellite Cells in a Mouse Muscle Atrophy Model

    PubMed Central

    Hauerslev, Simon; Vissing, John; Krag, Thomas O.

    2014-01-01

    Muscular dystrophies comprise a large group of inherited disorders that lead to progressive muscle wasting. We wanted to investigate if targeting satellite cells can enhance muscle regeneration and thus increase muscle mass. We treated mice with hepatocyte growth factor and leukemia inhibitory factor under three conditions: normoxia, hypoxia and during myostatin deficiency. We found that hepatocyte growth factor treatment led to activation of the Akt/mTOR/p70S6K protein synthesis pathway, up-regulation of the myognic transcription factors MyoD and myogenin, and subsequently the negative growth control factor, myostatin and atrophy markers MAFbx and MuRF1. Hypoxia-induced atrophy was partially restored by hepatocyte growth factor combined with leukemia inhibitory factor treatment. Dividing satellite cells were three-fold increased in the treatment group compared to control. Finally, we demonstrated that myostatin regulates satellite cell activation and myogenesis in vivo following treatment, consistent with previous findings in vitro. Our results suggest, not only a novel in vivo pharmacological treatment directed specifically at activating the satellite cells, but also a myostatin dependent mechanism that may contribute to the progressive muscle wasting seen in severely affected patients with muscular dystrophy and significant on-going regeneration. This treatment could potentially be applied to many conditions that feature muscle wasting to increase muscle bulk and strength. PMID:24963862

  6. Muscle atrophy reversed by growth factor activation of satellite cells in a mouse muscle atrophy model.

    PubMed

    Hauerslev, Simon; Vissing, John; Krag, Thomas O

    2014-01-01

    Muscular dystrophies comprise a large group of inherited disorders that lead to progressive muscle wasting. We wanted to investigate if targeting satellite cells can enhance muscle regeneration and thus increase muscle mass. We treated mice with hepatocyte growth factor and leukemia inhibitory factor under three conditions: normoxia, hypoxia and during myostatin deficiency. We found that hepatocyte growth factor treatment led to activation of the Akt/mTOR/p70S6K protein synthesis pathway, up-regulation of the myognic transcription factors MyoD and myogenin, and subsequently the negative growth control factor, myostatin and atrophy markers MAFbx and MuRF1. Hypoxia-induced atrophy was partially restored by hepatocyte growth factor combined with leukemia inhibitory factor treatment. Dividing satellite cells were three-fold increased in the treatment group compared to control. Finally, we demonstrated that myostatin regulates satellite cell activation and myogenesis in vivo following treatment, consistent with previous findings in vitro. Our results suggest, not only a novel in vivo pharmacological treatment directed specifically at activating the satellite cells, but also a myostatin dependent mechanism that may contribute to the progressive muscle wasting seen in severely affected patients with muscular dystrophy and significant on-going regeneration. This treatment could potentially be applied to many conditions that feature muscle wasting to increase muscle bulk and strength.

  7. Sensitivity of three activated partial thromboplastin time reagents to coagulation factor deficiencies.

    PubMed

    Turi, D C; Peerschke, E I

    1986-01-01

    Three activated partial thromboplastin time (APTT) reagent test systems, General Diagnostics Automated APTT, American Dade Actin FS, and Pacific Hemostasis (Thromboscreen KAPTT) reagent, containing different activators for the APTT assay, were evaluated for their precision and sensitivity to factor deficiencies in the intrinsic coagulation system. The data suggest that micronized silica and ellagic acid reagent systems were similar in sensitivity to Factor VIII, X, and XII deficiencies, whereas, the micronized kaolin reagent was significantly less sensitive to these deficiencies. Factor XI deficiency was detected equally well with the use of all three reagent systems. The ellagic acid reagent was somewhat more sensitive to Factor IX deficiency than the micronized silica reagent, and the micronized kaolin reagent was again least sensitive. Both the micronized silica and ellagic acid based reagents were insensitive to all but severe deficiencies in prekallikrein, whereas the micronized kaolin reagent was unable to detect this deficiency. All three reagents were insensitive to all but severe deficiencies in high-molecular-weight kininogen. The authors conclude that the reagent systems tested, containing micronized silica or ellagic acid as activators, are similar in sensitivity when used in a routine activated partial thromboplastin time to screen for factor deficiencies, whereas the reagent system containing micronized kaolin as an activator is less sensitive.

  8. Calcium activation of Ras mediated by neuronal exchange factor Ras-GRF.

    PubMed

    Farnsworth, C L; Freshney, N W; Rosen, L B; Ghosh, A; Greenberg, M E; Feig, L A

    1995-08-10

    Tyrosine kinase receptors stimulate the Ras signalling pathway by enhancing the activity of the SOS nucleotide-exchange factor. This occurs, at least in part, by the recruitment of an SOS-GRB2 complex to Ras in the plasma membrane. Here we describe a different signalling pathway to Ras that involves activation of the Ras-GRF exchange factor in response to Ca2+ influx. In particular, we show that the ability of Ras-GRF to activate Ras in vivo is markedly enhanced by raised Ca2+ concentrations. Activation is mediated by calmodulin binding to an IQ motif in Ras-GRF, because substitutions in conserved amino acids in this motif prevent both calmodulin binding to Ras-GRF and Ras-GRF activation in vivo. So far, full-length Ras-GRF has been detected only in brain neurons. Our findings implicate Ras-GRF in the regulation of neuronal functions that are influenced by Ca2+ signals.

  9. Evolution of Osteocrin as an activity-regulated factor in the primate brain.

    PubMed

    Ataman, Bulent; Boulting, Gabriella L; Harmin, David A; Yang, Marty G; Baker-Salisbury, Mollie; Yap, Ee-Lynn; Malik, Athar N; Mei, Kevin; Rubin, Alex A; Spiegel, Ivo; Durresi, Ershela; Sharma, Nikhil; Hu, Linda S; Pletikos, Mihovil; Griffith, Eric C; Partlow, Jennifer N; Stevens, Christine R; Adli, Mazhar; Chahrour, Maria; Sestan, Nenad; Walsh, Christopher A; Berezovskii, Vladimir K; Livingstone, Margaret S; Greenberg, Michael E

    2016-11-10

    Sensory stimuli drive the maturation and function of the mammalian nervous system in part through the activation of gene expression networks that regulate synapse development and plasticity. These networks have primarily been studied in mice, and it is not known whether there are species- or clade-specific activity-regulated genes that control features of brain development and function. Here we use transcriptional profiling of human fetal brain cultures to identify an activity-dependent secreted factor, Osteocrin (OSTN), that is induced by membrane depolarization of human but not mouse neurons. We find that OSTN has been repurposed in primates through the evolutionary acquisition of DNA regulatory elements that bind the activity-regulated transcription factor MEF2. In addition, we demonstrate that OSTN is expressed in primate neocortex and restricts activity-dependent dendritic growth in human neurons. These findings suggest that, in response to sensory input, OSTN regulates features of neuronal structure and function that are unique to primates.

  10. A Transmissible Plant Shoot Factor Promotes Uptake Hydrogenase Activity in Rhizobium Symbionts 1

    PubMed Central

    Bedmar, Eulogio J.; Phillips, Donald A.

    1984-01-01

    Shoot/root grafting studies showed organ and host cultivar effects on net H2 evolution from Pisum sativum L. root nodules. Net H2 evolution from those nodules represents the sum of H2 formed by Rhizobium nitrogenase and H2 oxidized by any uptake hydrogenase present in the bacteria. Grafts between pea cultivars `JI1205' or `Alaska' and `Feltham First' in symbioses with R. leguminosarum 128C53 showed that shoots of both JI1205 and Alaska increased H2 uptake significantly (P ≤ 0.05) in Feltham First root nodules. The same plants also had less net H2 evolution at similar rates of C2H2 reduction than plants formed by grafting Feltham First shoots on Feltham First roots. Although JI1205 and Alaska shoots increased H2-uptake activity of Feltham First root nodules 28 days after the graft was made, intermediate to high levels of H2 uptake activity were still present in nodules on roots of both JI1205 and Alaska grafted to Feltham First shoots. These results indicate the presence of a transmissible shoot factor(s) which can increase uptake hydrogenase activity in a Rhizobium symbiont and show that root genotype also can influence that parameter. Parallel grafting experiments using the same pea cultivars in symbioses with R. leguminosarum strain 300, which lacks uptake hydrogenase activity, suggested that a transmissible shoot factor(s) altered H2 formation from nitrogenase by changing the electron allocation coefficient of that enzyme complex. The root and shoot factor(s) detected in this study had no permanent effect on strain 128C53. Bacterial cells isolated from Feltham First nodules with low H2 uptake activity formed root nodules on JI1205 and Alaska with high H2 uptake activity. Bacteroids isolated from nodules on intact JI1205, Alaska, or Feltham First plants with high, medium, or low H2 uptake activity, respectively, maintained those phenotypes during in vitro assays. PMID:16663677

  11. A transmissible plant shoot factor promotes uptake hydrogenase activity in Rhizobium symbionts.

    PubMed

    Bedmar, E J; Phillips, D A

    1984-07-01

    Shoot/root grafting studies showed organ and host cultivar effects on net H(2) evolution from Pisum sativum L. root nodules. Net H(2) evolution from those nodules represents the sum of H(2) formed by Rhizobium nitrogenase and H(2) oxidized by any uptake hydrogenase present in the bacteria. Grafts between pea cultivars ;JI1205' or ;Alaska' and ;Feltham First' in symbioses with R. leguminosarum 128C53 showed that shoots of both JI1205 and Alaska increased H(2) uptake significantly (P activity of Feltham First root nodules 28 days after the graft was made, intermediate to high levels of H(2) uptake activity were still present in nodules on roots of both JI1205 and Alaska grafted to Feltham First shoots. These results indicate the presence of a transmissible shoot factor(s) which can increase uptake hydrogenase activity in a Rhizobium symbiont and show that root genotype also can influence that parameter.Parallel grafting experiments using the same pea cultivars in symbioses with R. leguminosarum strain 300, which lacks uptake hydrogenase activity, suggested that a transmissible shoot factor(s) altered H(2) formation from nitrogenase by changing the electron allocation coefficient of that enzyme complex.The root and shoot factor(s) detected in this study had no permanent effect on strain 128C53. Bacterial cells isolated from Feltham First nodules with low H(2) uptake activity formed root nodules on JI1205 and Alaska with high H(2) uptake activity. Bacteroids isolated from nodules on intact JI1205, Alaska, or Feltham First plants with high, medium, or low H(2) uptake activity, respectively, maintained those phenotypes during in vitro assays.

  12. Active fault and water loading are important factors in triggering earthquake activity around Aswan Lake

    NASA Astrophysics Data System (ADS)

    Kebeasy, R. M.; Gharib, A. A.

    Aswan Lake started impounding in 1964 and reached the highest water level so far in 1978 with a capacity of 133.8 km 3, thus forming the second largest man-made lake in the world. An earthquake of magnitude 5.3 (Ms) took place on 14 November 1981 along the most active part of the E-W Kalabsha fault beneath the Kalabsha bay (the largest bay of the lake). This earthquake was followed by a tremendous number of smaller events that continue till now. A radio-telemetry network of 13 seismic short period stations and a piezometer network of six wells were established around the northern part of the lake. Epicenters were found to cluster around active faults near the lake. The space-time distribution and the relation of the seismicity with the lake water level fluctuations were studied. Six years after flooding the eastern segment of the Kalabsha fault, strong seismicity began following the main shock of 14 November 1981. It occurred four days after the reservoir had reached its seasonal max level. The effect of the North African drought (1982 to present) is clearly seen in the reservoir water level. As it decreased and left the most active fault segments uncovered, the activity (Gebel Marawa area) decreased sharply. Also, the shallow activity was found to be more sensitive to rapid discharging than to the filling. This study indicates that geology, topography, lineations in seismicity, offsets in the faults, changes in fault trends and focal mechanisms are closely related. No relation was found between earthquake activity and both-ground water table fluctuations and water temperatures measured in wells located around the Kalabsha area.

  13. Factors Influencing Entering Teacher Candidates' Preferences for Instructional Activities: A glimpse into their orientations towards teaching

    NASA Astrophysics Data System (ADS)

    Talanquer, Vicente; Novodvorsky, Ingrid; Tomanek, Debra

    2010-07-01

    The present study was designed to identify and characterize the major factors that influence entering science teacher candidates' preferences for different types of instructional activities, and to analyze what these factors suggest about teacher candidates' orientations towards science teaching. The study involved prospective teachers enrolled in the introductory science teaching course in an undergraduate science teacher preparation program. Our analysis was based on data collected using a teaching and learning beliefs questionnaire, together with structured interviews. Our results indicate that entering science teacher candidates have strong preferences for a few activity types. The most influential factors driving entering science teacher candidates' selections were the potential of the instructional activities to motivate students, be relevant to students' personal lives, result in transfer of skills to non-science situations, actively involve students in goal-directed learning, and implement curriculum that represents what students need to know. This set of influencing factors suggests that entering science teacher candidates' orientations towards teaching are likely driven by one or more of these three central teaching goals: (1) motivating students, (2) developing science process skills, and (3) engaging students in structured science activities. These goals, and the associated beliefs about students, teaching, and learning, can be expected to favor the development or enactment of three major orientations towards teaching in this population of future science teachers: "motivating students," "process," and "activity-driven."

  14. Association of tissue factor activity with the surface of cultured cells.

    PubMed Central

    Maynard, J R; Heckman, C A; Pitlick, F A; Nemerson, Y

    1975-01-01

    Tissue factor occurs in a dormant state on the surface of cultured normal human fibroblasts and WISH 1 amnion cells. The activity of undisturbed monolayers or cells lifted with brief trypsin treatment (0.125 per cent trypsin for 1 min) increases up to 60-fold upon prolonged digestion with dilute trypsin (0.0025 per cent trypsin for 30 min); activity appears subsequent to cell detachment. Up to 70 per cent of the total cellular tissue factor becomes active under these conditions and is released from the cells. The ruthenium red staining coat of the cells is lost during detachment, but cell viability (more than 90 per cent exclude trypan blue) and cell morphology do not change during the subsequent development of tissue factor activity. Furthermore, less than 10 percent of four intracellular enzymes and less than 20 per cent of two plasma membrane enzymes are released during this period of time. We therefore conclude that cells in culture do have tissue factor activity, that it exists in a latent form, and that total cell disruption is not necessary for this activity to initiate blood coagulation. Images PMID:47334

  15. Cooperative activation of Xenopus rhodopsin transcription by paired-like transcription factors

    PubMed Central

    2014-01-01

    Background In vertebrates, rod photoreceptor-specific gene expression is regulated by the large Maf and Pax-like transcription factors, Nrl/LNrl and Crx/Otx5. The ubiquitous occurrence of their target DNA binding sites throughout rod-specific gene promoters suggests that multiple transcription factor interactions within the promoter are functionally important. Cooperative action by these transcription factors activates rod-specific genes such as rhodopsin. However, a quantitative mechanistic explanation of transcriptional rate determinants is lacking. Results We investigated the contributions of various paired-like transcription factors and their cognate cis-elements to rhodopsin gene activation using cultured cells to quantify activity. The Xenopus rhodopsin promoter (XOP) has a bipartite structure, with ~200 bp proximal to the start site (RPP) coordinating cooperative activation by Nrl/LNrl-Crx/Otx5 and the adjacent 5300 bp upstream sequence increasing the overall expression level. The synergistic activation by Nrl/LNrl-Crx/Otx5 also occurred when XOP was stably integrated into the genome. We determined that Crx/Otx5 synergistically activated transcription independently and additively through the two Pax-like cis-elements, BAT1 and Ret4, but not through Ret1. Other Pax-like family members, Rax1 and Rax2, do not synergistically activate XOP transcription with Nrl/LNrl and/or Crx/Otx5; rather they act as co-activators via the Ret1 cis-element. Conclusions We have provided a quantitative model of cooperative transcriptional activation of the rhodopsin promoter through interaction of Crx/Otx5 with Nrl/LNrl at two paired-like cis-elements proximal to the NRE and TATA binding site. Further, we have shown that Rax genes act in cooperation with Crx/Otx5 with Nrl/LNrl as co-activators of rhodopsin transcription. PMID:24499263

  16. Prevalence of factors related to active reproductive health behavior: a cross-sectional study Indonesian adolescent

    PubMed Central

    Kimura, Rumiko; Tsuda, Akiko; Tabuchi, Noriko

    2016-01-01

    OBJECTIVES Complex and diverse factors are related to reproductive health (RH) behavior among adolescents according to the social and cultural context of each countries. This study examined the prevalence of active RH and factors related to active RH behavior among Indonesian adolescents. METHODS A cross-sectional study was conducted among 1,040 of students who were selected through a multi-stage random sampling technique. A self-administered questionnaire was developed, including the World Health Organization Illustrative Questionnaire for Interview-Surveys with Young People, pubertal development scale, and sexual activity scale, modified in accordance to the Indonesian context. The data were analyzed using descriptive and comparative statistics, as well as logistic regression analyses. RESULTS The prevalence of active RH behavior were more higher in boys (56.6%; 95% confidence interval [CI], 50.6% to 62.6%) than in girls (43.7%; 95% CI, 37.6% to 49.8%). Negative attitudes towards RH were a factor related to active RH behavior in both boys and girls. Smoking and kind relationship envisioned before marriage (pacaran [courtship] and nikah siri [non-registered marriage]) were factors related to active RH behavior in boys; whereas the absence of access to information on substance abuse was an additional factor in girls. Moreover, an interaction was found between access to information on development and smoking (boys) and attitudes on RH (girls) as independent variables associated with active RH behavior. CONCLUSIONS Sex education for adolescents in Indonesia, particularly in the context of a health promotion program, should be developed based on prevalent social, cultural, and religious values to prevent active RH behavior. Such programs should focus on the kind of relationship envisioned before marriage and smoking for boys and access to information on subtance abuse for girls. PMID:27866406

  17. Factors Associated with Physical Activity among Macedonian Adolescents in Albanian Ethnic Community

    PubMed Central

    GONTAREV, Seryozha; KALAC, Ruzdija; AMETI, Vullnet; REDJEPI, Agim

    2016-01-01

    Background: The purpose of this study was to determine the relationship of demographic, psychological, social and environmental factors with physical activity and to determine whether indicators of physical activity differ by gender among Macedonian adolescents from Albanian ethnic community from 11 to 14 yr (N = 886). Methods: Research were conducted in 2014 in several primary schools randomly selected from Tetovo and Gostivar region of the R. Macedonia. Students completed a questionnaire which examined their level of participation in physical activity and sedentary behavior along with a number of potential correlates. Hierarchical regression was used to explore the relationship between hypothesised factors and physical activity. Results: The boys unlike the girls showed significantly higher levels of physical activity (P=0.001). Respondents of both genders who perceive greater benefits from the physical activity (P=0.010). They have more confidence in their abilities (P=0.001), enjoy more in the physical activities (P=0.016), perceive greater social support from friends (P=0.008) and parents (P=0.001) and have higher levels of physical activity. Conclusions: The results indicate the importance of developing a national plan and program to promote physical activity in order to help young people to change unhealthy lifestyle habits and increase the physical activity, thus improving their health. PMID:27252917

  18. Factors Associated with Nursing Activities in Humanitarian Aid and Disaster Relief

    PubMed Central

    Noguchi, Norihito; Inoue, Satoshi; Shimanoe, Chisato; Shibayama, Kaoru; Shinchi, Koichi

    2016-01-01

    Background Although nurses play an important role in humanitarian aid and disaster relief (HA/DR), little is known about the nursing activities that are performed in HA/DR. We aimed to clarify the nursing activities performed by Japanese nurses in HA/DR and to examine the factors associated with the frequency of nursing activities. Methods A self-administered questionnaire survey was completed by 147 nurses with HA/DR experience. The survey extracted information on demographic characteristics, past experience (e.g., disaster medical training experience, HA/DR experience), circumstances surrounding their dispatched to HA/DR (e.g., team size, disaster type, post-disaster phase, mission term), and the frequency of nursing activities performed under HA/DR. The frequency of nursing activities was rated on a 5-point Likert scale. Evaluation of nursing activities was conducted based on the “nursing activity score”, which represents the frequency of each nursing activity. Factors related to the nursing activity score were evaluated by multiple logistic regression analysis. Results Nurses were involved in 27 nursing activities in HA/DR, 10 of which were performed frequently. On analysis, factors significantly associated with nursing activity score were nursing license as a registered nurse (OR 7.79, 95% CI 2.95–20.57), two or more experiences with disaster medical training (OR 2.90 95%, CI 1.12–7.49) and a post-disaster phase of three weeks or longer (OR 8.77, 95% CI 2.59–29.67). Conclusions These results will contribute to the design of evidence-based disaster medical training that improves the quality of nursing activities. PMID:26959351

  19. Evidence from intrinsic activity that asymmetry of the human brain is controlled by multiple factors

    PubMed Central

    Liu, Hesheng; Stufflebeam, Steven M.; Sepulcre, Jorge; Hedden, Trey; Buckner, Randy L.

    2009-01-01

    Cerebral lateralization is a fundamental property of the human brain and a marker of successful development. Here we provide evidence that multiple mechanisms control asymmetry for distinct brain systems. Using intrinsic activity to measure asymmetry in 300 adults, we mapped the most strongly lateralized brain regions. Both men and women showed strong asymmetries with a significant, but small, group difference. Factor analysis on the asymmetric regions revealed 4 separate factors that each accounted for significant variation across subjects. The factors were associated with brain systems involved in vision, internal thought (the default network), attention, and language. An independent sample of right- and left-handed individuals showed that hand dominance affects brain asymmetry but differentially across the 4 factors supporting their independence. These findings show the feasibility of measuring brain asymmetry using intrinsic activity fluctuations and suggest that multiple genetic or environmental mechanisms control cerebral lateralization. PMID:19918055

  20. Evidence from intrinsic activity that asymmetry of the human brain is controlled by multiple factors.

    PubMed

    Liu, Hesheng; Stufflebeam, Steven M; Sepulcre, Jorge; Hedden, Trey; Buckner, Randy L

    2009-12-01

    Cerebral lateralization is a fundamental property of the human brain and a marker of successful development. Here we provide evidence that multiple mechanisms control asymmetry for distinct brain systems. Using intrinsic activity to measure asymmetry in 300 adults, we mapped the most strongly lateralized brain regions. Both men and women showed strong asymmetries with a significant, but small, group difference. Factor analysis on the asymmetric regions revealed 4 separate factors that each accounted for significant variation across subjects. The factors were associated with brain systems involved in vision, internal thought (the default network), attention, and language. An independent sample of right- and left-handed individuals showed that hand dominance affects brain asymmetry but differentially across the 4 factors supporting their independence. These findings show the feasibility of measuring brain asymmetry using intrinsic activity fluctuations and suggest that multiple genetic or environmental mechanisms control cerebral lateralization.

  1. Factors Related to Meeting Physical Activity Guidelines in Active College Students: A Social Cognitive Perspective

    ERIC Educational Resources Information Center

    Farren, G. L.; Zhang, T.; Martin, S. B.; Thomas, K. T.

    2017-01-01

    Objective: To examine the relations of sex, exercise self-efficacy, outcome expectations, and social support with meeting physical activity guidelines (PAGs). Participants: Three hundred ninety-six college students participated in this study in the summer 2013. Methods: Students completed online questionnaires that assessed physical activity…

  2. Asynchronous combinatorial action of four regulatory factors activates Bcl11b for T cell commitment

    PubMed Central

    Kueh, Hao Yuan; Yui, Mary A.; Ng, Kenneth K.H.; Pease, Shirley S.; Zhang, Jingli A.; Damle, Sagar S.; Freedman, George; Siu, Sharmayne; Bernstein, Irwin D.; Elowitz, Michael B.; Rothenberg, Ellen V.

    2016-01-01

    During T cell development, multipotent progenitors relinquish competence for other fates and commit to the T cell lineage by turning on the transcription factor Bcl11b. To clarify lineage commitment mechanisms, we followed developing T cells at single-cell level using Bcl11b knock-in fluorescent reporter mice. Notch signaling and Notch-activated transcription factors collaborate to activate Bcl11b expression, irrespective of Notch-dependent proliferation. These inputs work via three distinct, asynchronous mechanisms: an early locus poising function dependent on TCF-1 and GATA-3; a stochastic permissivity function dependent on Notch signaling; and a separate amplitude-control function dependent on Runx1, a factor already present in multipotent progenitors. Despite all being necessary for Bcl11b activation, these inputs act in a stage specific manner, providing a multi-tiered mechanism for developmental gene regulation. PMID:27376470

  3. How glucocorticoid receptors modulate the activity of other transcription factors: a scope beyond tethering.

    PubMed

    Ratman, Dariusz; Vanden Berghe, Wim; Dejager, Lien; Libert, Claude; Tavernier, Jan; Beck, Ilse M; De Bosscher, Karolien

    2013-11-05

    The activity of the glucocorticoid receptor (GR), a nuclear receptor transcription factor belonging to subclass 3C of the steroid/thyroid hormone receptor superfamily, is typically triggered by glucocorticoid hormones. Apart from driving gene transcription via binding onto glucocorticoid response elements in regulatory regions of particular target genes, GR can also inhibit gene expression via transrepression, a mechanism largely based on protein:protein interactions. Hereby GR can influence the activity of other transcription factors, without contacting DNA itself. GR is known to inhibit the activity of a growing list of immune-regulating transcription factors. Hence, GCs still rule the clinic for treatments of inflammatory disorders, notwithstanding concomitant deleterious side effects. Although patience is a virtue when it comes to deciphering the many mechanisms GR uses to influence various signaling pathways, the current review is testimony of the fact that groundbreaking mechanistic work has been accumulating over the past years and steadily continues to grow.

  4. Human factors activities in teleoperator development at the Oak Ridge National Laboratory

    SciTech Connect

    Draper, J.V.; Herndon, J.N.

    1986-01-01

    The Consolidated Fuel Reprocessing Program (CFRP) at the Oak Ridge National Laboratory is developing advanced teleoperator systems for maintenance of future nuclear reprocessing facilities. Remote maintenance systems developed by the CFRP emphasize man-in-the-loop teleoperation. Consequently, human factors issues which affect teleoperator performance must be addressed. This papers surveys research and development activities carried out by the human factors group within the Remote Control Engineering Task of the CFRP.

  5. Group D prothrombin activators from snake venom are structural homologues of mammalian blood coagulation factor Xa.

    PubMed Central

    Rao, Veena S; Joseph, Jeremiah S; Kini, R Manjunatha

    2003-01-01

    Procoagulant venoms of several Australian elapids contain proteinases that specifically activate prothrombin; among these, Group D activators are functionally similar to coagulation factor Xa (FXa). Structural information on this class of prothrombin activators will contribute significantly towards understanding the mechanism of FXa-mediated prothrombin activation. Here we present the purification of Group D prothrombin activators from three Australian snake venoms (Hoplocephalus stephensi, Notechis scutatus scutatus and Notechis ater niger) using a single-step method, and their N-terminal sequences. The N-terminal sequence of the heavy chain of hopsarin D (H. stephensi) revealed that a fully conserved Cys-7 was substituted with a Ser residue. We therefore determined the complete amino acid sequence of hopsarin D. Hopsarin D shows approximately 70% similarity with FXa and approximately 98% similarity with trocarin D, a Group D prothrombin activator from Tropidechis carinatus. It possesses the characteristic Gla domain, two epidermal growth factor-like domains and a serine proteinase domain. All residues important for catalysis are conserved, as are most regions involved in interactions with factor Va and prothrombin. However, there are some structural differences. Unlike FXa, hopsarin D is glycosylated in both its chains: in light-chain residue 52 and heavy-chain residue 45. The glycosylation on the heavy chain is a large carbohydrate moiety adjacent to the active-site pocket. Overall, hopsarin D is structurally and functionally similar to mammalian coagulation FXa. PMID:12403650

  6. Assessments of fatigue and disease activity in patients with systemic lupus erythematosus enrolled in the Phase 2 clinical trial with blisibimod.

    PubMed

    Petri, M A; Martin, R S; Scheinberg, M A; Furie, R A

    2017-01-01

    This report evaluates the effects of blisibimod (A-623, AMG 623), a potent and selective inhibitor of B-cell activating factor (BAFF), on patient-reported fatigue and disease activity in the Phase 2b PEARL-SC clinical trial in patients with systemic lupus erythematosus (SLE). A total of 547 individuals who met the American College of Rheumatology (ACR) classification criteria for SLE, were positive for anti-double-stranded DNA or antinuclear antibodies, and had a Safety of Estrogens in Lupus Erythematosus National Assessment-Systemic Lupus Erythematosus Disease Activity Index (SELENA-SLEDAI) score ≥6 at baseline, were randomized to receive placebo or blisibimod for at least 24 weeks. Patient self-reported fatigue was evaluated using the Functional Assessment of Chronic Illness Therapy (FACIT)-Fatigue scale, and disease activity was evaluated using Physician's Global Assessment, SELENA-SLEDAI, and British Isles Lupus Assessment Group Score. Statistically significant improvements in FACIT-Fatigue score were observed among individuals randomized to blisibimod, especially in the 200 mg QW group where favorable effects on disease activity with blisibimod compared to placebo were observed as early as Week 8. The mean improvement from baseline of 6.9 points at Week 24, compared with 4.4 points with placebo, met the criteria for minimal clinically important improvement difference defined for patients with SLE. Despite concomitant improvements in FACIT-Fatigue, SLE Responder Index (SRI) and SLE biomarkers (reported previously), FACIT-Fatigue score correlated only weakly with disease activity. While poor correlation between fatigue and disease activity is not new, the observation that correlation remains poor despite concurrent population improvements in disease and fatigue brings a new facet to our understanding of SLE.

  7. Association of lifestyle and demographic factors with estrogenic and glucocorticogenic activity in Mexican American women.

    PubMed

    Fejerman, L; Sanchez, S S; Thomas, R; Tachachartvanich, P; Riby, J; Gomez, S L; John, E M; Smith, M T

    2016-09-01

    Breast cancer risk is higher in US-born than in foreign-born Hispanics/Latinas and also increases with greater length of US residency. It is only partially known what factors contribute to these patterns of risk. To gain new insights, we tested the association between lifestyle and demographic variables and breast cancer status, with measures of estrogenic (E) and glucocorticogenic (G) activity in Mexican American women. We used Chemical-Activated LUciferase gene eXpression assays to measure E and G activity in total plasma from 90 Mexican American women, without a history of breast cancer at the time of recruitment, from the San Francisco Bay Area Breast Cancer Study. We tested associations of nativity, lifestyle and sociodemographic factors with E and G activity using linear regression models. We did not find a statistically significant difference in E or G activity by nativity. However, in multivariable models, E activity was associated with Indigenous American ancestry (19% decrease in E activity per 10% increase in ancestry, P = 0.014) and with length of US residency (28% increase in E activity for every 10 years, P = 0.035). G activity was associated with breast cancer status (women who have developed breast cancer since recruitment into the study had 21% lower G activity than those who have not, P = 0.054) and alcohol intake (drinkers had 25% higher G activity than non-drinkers, P = 0.015). These associations suggest that previously reported breast cancer risk factors such as genetic ancestry and alcohol intake might in part be associated with breast cancer risk through mechanisms linked to the endocrine system.

  8. Habitual physical activity and cardiometabolic risk factors in adults with cerebral palsy.

    PubMed

    Ryan, Jennifer M; Crowley, Vivion E; Hensey, Owen; Broderick, Julie M; McGahey, Ailish; Gormley, John

    2014-09-01

    Adults with cerebral palsy (CP) are known to participate in reduced levels of total physical activity. There is no information available however, regarding levels of moderate-to-vigorous physical activity (MVPA) in this population. Reduced participation in MVPA is associated with several cardiometabolic risk factors. The purpose of this study was firstly to compare levels of sedentary, light, MVPA and total activity in adults with CP to adults without CP. Secondly, the objective was to investigate the association between physical activity components, sedentary behavior and cardiometabolic risk factors in adults with CP. Adults with CP (n=41) age 18-62 yr (mean ± SD=36.5 ± 12.5 yr), classified in Gross Motor Function Classification System level I (n=13), II (n=18) and III (n=10) participated in this study. Physical activity was measured by accelerometry in adults with CP and in age- and sex-matched adults without CP over 7 days. Anthropometric indicators of obesity, blood pressure and several biomarkers of cardiometabolic disease were also measured in adults with CP. Adults with CP spent less time in light, moderate, vigorous and total activity, and more time in sedentary activity than adults without CP (p<0.01 for all). Moderate physical activity was associated with waist-height ratio when adjusted for age and sex (β=-0.314, p<0.05). When further adjustment was made for total activity, moderate activity was associated with waist-height ratio (β=-0.538, p<0.05), waist circumference (β=-0.518, p<0.05), systolic blood pressure (β=-0.592, p<0.05) and diastolic blood pressure (β=-0.636, p<0.05). Sedentary activity was not associated with any risk factor. The findings provide evidence that relatively young adults with CP participate in reduced levels of MVPA and spend increased time in sedentary behavior, potentially increasing their risk of developing cardiometabolic disease.

  9. Inhibition of fatty acid oxidation activates transforming growth factor-beta in cerebrospinal fluid and decreases spontaneous motor activity.

    PubMed

    Fujikawa, Teppei; Fujita, Ryo; Iwaki, Yoko; Matsumura, Shigenobu; Fushiki, Tohru; Inoue, Kazuo

    2010-10-05

    We have previously reported that transforming growth factor (TGF)-beta in the cerebrospinal fluid (CSF) is involved in the mechanism underlying the regulation of spontaneous motor activity (SMA) by the central nervous system after exercise. However, it remained unclear what physiological condition triggers the activation of TGF-beta. We hypothesized that the shortage of energy derived from fatty acid (FA) oxidation observed in the early phase of exercise activated TGF-beta in the CSF. To test this hypothesis, we investigated whether mercaptoacetate (MA), an inhibitor of FA oxidation, could induce an activation of TGF-beta in the CSF and a decrease in SMA. Intraperitoneal (i.p.) administration of MA activated TGF-beta in CSF in rats and depressed SMA; 2-deoxyglucose, an inhibitor of carbohydrate oxidation, on the other hand, depressed SMA but failed to activate CSF TGF-beta. Intracisternal administration of anti-TGF-beta antibody abolished the depressive effect of MA on SMA. We also found that the depression of SMA and the activation of TGF-beta in the CSF by i.p. MA administration were eliminated by vagotomy. Our data suggest that TGF-beta in the CSF is activated by the inhibition of FA oxidation via the vagus nerve and that this subsequently induces depression of SMA.

  10. Cytokinin Response Factor 5 has transcriptional activity governed by its C-terminal domain.

    PubMed

    Striberny, Bernd; Melton, Anthony E; Schwacke, Rainer; Krause, Kirsten; Fischer, Karsten; Goertzen, Leslie R; Rashotte, Aaron M

    2017-02-01

    Cytokinin Response Factors (CRFs) are AP2/ERF transcription factors involved in cytokinin signal transduction. CRF proteins consist of a N-terminal dimerization domain (CRF domain), an AP2 DNA-binding domain, and a clade-specific C-terminal region of unknown function. Using a series of sequential deletions in yeast-2-hybrid assays, we provide evidence that the C-terminal region of Arabidopsis CRF5 can confer transactivation activity. Although comparative analyses identified evolutionarily conserved protein sequence within the C-terminal region, deletion experiments suggest that this transactivation domain has a partially redundant modular structure required for activation of target gene transcription.

  11. PLCζ or PAWP: revisiting the putative mammalian sperm factor that triggers egg activation and embryogenesis.

    PubMed

    Kashir, Junaid; Nomikos, Michail; Swann, Karl; Lai, F Anthony

    2015-05-01

    In mammals, egg activation is initiated by multiple cytosolic Ca(2+) transients (Ca(2+) oscillations) that are triggered following delivery of a putative sperm factor from the fertilizing sperm. The identity of this 'sperm factor' thus holds much significance, not only as a vital component in creating a new life, but also for its potential therapeutic and diagnostic value in human infertility. Recent data have emerged suggesting the sperm factor may be a post-acrosomal sheath WW domain-binding protein (PAWP). However, a significant body of research points to a testis-specific phospholipase C zeta (PLCζ) as the sperm factor. Herein, we examine the evidence presented in favour of PAWP in relation to PLCζ and the requisite physiological properties of the mammalian sperm factor.

  12. Choline Acetyltransferase Activity in Striatum of Neonatal Rats Increased by Nerve Growth Factor

    NASA Astrophysics Data System (ADS)

    Mobley, William C.; Rutkowski, J. Lynn; Tennekoon, Gihan I.; Buchanan, Karen; Johnston, Michael V.

    1985-07-01

    Some neurodegenerative disorders may be caused by abnormal synthesis or utilization of trophic molecules required to support neuronal survival. A test of this hypothesis requires that trophic agents specific for the affected neurons be identified. Cholinergic neurons in the corpus striatum of neonatal rats were found to respond to intracerebroventricular administration of nerve growth factor with prominent, dose-dependent, selective increases in choline acetyltransferase activity. Cholinergic neurons in the basal forebrain also respond to nerve growth factor in this way. These actions of nerve growth factor may indicate its involvement in the normal function of forebrain cholinergic neurons as well as in neurodegenerative disorders involving such cells.

  13. Activation of the exchange factor Ras-GRF by calcium requires an intact Dbl homology domain.

    PubMed

    Freshney, N W; Goonesekera, S D; Feig, L A

    1997-04-21

    Ras-GRF is a guanine nucleotide exchange factor that activates Ras proteins. Its activity on Ras in cells is enhanced upon calcium influx. Activation follows calcium-induced binding of calmodulin to an IQ motif near the N-terminus of Ras-GRF. Ras-GRF also contains a Dbl homology (DH) domain C-terminal to the IQ motif. In many proteins, DH domains act as exchange factors for Rho-GTPase family members. However, we failed to detect exchange activity of this domain on well characterized Rho family members. Instead, we found that mutations analogous to those that block exchange activity of Dbl prevented Ras-GRF activation by calcium/ calmodulin in vivo. All DH domains are followed immediately by a pleckstrin homology (PH) domain. We found that a mutation at a conserved site within the PH domain following the DH domain also prevented Ras-GRF activation by calcium in vivo. These results suggest that in addition to playing a role as activators of Rho proteins, DH domains can also contribute to the coupling of cellular signals to Ras activation.

  14. Combined influence of healthy diet and active lifestyle on cardiovascular disease risk factors in adolescents.

    PubMed

    Cuenca-García, M; Ortega, F B; Ruiz, J R; González-Gross, M; Labayen, I; Jago, R; Martínez-Gómez, D; Dallongeville, J; Bel-Serrat, S; Marcos, A; Manios, Y; Breidenassel, C; Widhalm, K; Gottrand, F; Ferrari, M; Kafatos, A; Molnár, D; Moreno, L A; De Henauw, S; Castillo, M J; Sjöström, M

    2014-06-01

    To investigate the combined influence of diet quality and physical activity on cardiovascular disease (CVD) risk factors in adolescents, adolescents (n = 1513; 12.5-17.5 years) participating in the Healthy Lifestyle in Europe by Nutrition in Adolescence study were studied. Dietary intake was registered using a 24-h recall and a diet quality index was calculated. Physical activity was assessed by accelerometry. Lifestyle groups were computed as: healthy diet and active, unhealthy diet but active, healthy diet but inactive, and unhealthy diet and inactive. CVD risk factor measurements included cardiorespiratory fitness, adiposity indicators, blood lipid profile, blood pressure, and insulin resistance. A CVD risk score was computed. The healthy diet and active group had a healthier cardiorespiratory profile, fat mass index (FMI), triglycerides, and high-density lipoprotein cholesterol (HDL-C) levels and total cholesterol (TC)/HDL-C ratio (all P ≤ 0.05). Overall, active adolescents showed higher cardiorespiratory fitness, lower FMI, TC/HDL-C ratio, and homeostasis model assessment index and healthier blood pressure than their inactive peers with either healthy or unhealthy diet (all P ≤ 0.05). Healthy diet and active group had healthier CVD risk score compared with the inactive groups (all P ≤ 0.02). Thus, a combination of healthy diet and active lifestyle is associated with decreased CVD risk in adolescents. Moreover, an active lifestyle may reduce the adverse consequences of an unhealthy diet.

  15. Nuclear factor of activated T-cells (NFAT) plays a role in SV40 infection

    SciTech Connect

    Manley, Kate; O'Hara, Bethany A.; Atwood, Walter J.

    2008-03-01

    Recent evidence highlighted a role for the transcription factor, nuclear factor of activated T-cells (NFAT), in the transcription of the human polyomavirus JCV. Here we show that NFAT is also important in the transcriptional control of the related polyomavirus, Simian Virus 40 (SV40). Inhibition of NFAT activity reduced SV40 infection of Vero, 293A, and HeLa cells, and this block occurred at the stage of viral transcription. Both NFAT3 and NFAT4 bound to the SV40 promoter through {kappa}B sites located within the 72 bp repeated enhancer region. In Vero cells, NFAT was involved in late transcription, but in HeLa and 293A cells both early and late viral transcription required NFAT activity. SV40 large T-Ag was found to increase NFAT activity and provided a positive feedback loop to transactivate the SV40 promoter.

  16. Specific induction of endogenous viral restriction factors using CRISPR/Cas-derived transcriptional activators.

    PubMed

    Bogerd, Hal P; Kornepati, Anand V R; Marshall, Joy B; Kennedy, Edward M; Cullen, Bryan R

    2015-12-29

    Whereas several mammalian proteins can restrict the replication of HIV-1 and other viruses, these are often not expressed in relevant target cells. A potential method to inhibit viral replication might therefore be to use synthetic transcription factors to induce restriction factor expression. In particular, mutants of the RNA-guided DNA binding protein Cas9 that have lost their DNA cleavage activity could be used to recruit transcription activation domains to specific promoters. However, initial experiments revealed only weak activation unless multiple promoter-specific single guide RNAs (sgRNAs) were used. Recently, the recruitment of multiple transcription activation domains by a single sgRNA, modified to contain MS2-derived stem loops that recruit fusion proteins consisting of the MS2 coat protein linked to transcription activation domains, was reported to induce otherwise silent cellular genes. Here, we demonstrate that such "synergistic activation mediators" can induce the expression of two restriction factors, APOBEC3G (A3G) and APOBEC3B (A3B), in human cells that normally lack these proteins. We observed modest activation of endogenous A3G or A3B expression using single sgRNAs but high expression when two sgRNAs were used. Whereas the induced A3G and A3B proteins both blocked infection by an HIV-1 variant lacking a functional vif gene by inducing extensive dC-to-dU editing, only the induced A3B protein inhibited wild-type HIV-1. These data demonstrate that Cas9-derived transcriptional activators have the potential to be used for screens for endogenous genes that affect virus replication and raise the possibility that synthetic transcription factors might prove clinically useful if efficient delivery mechanisms could be developed.

  17. Factors influencing physical activity level among secondary school adolescents in Petaling District, Selangor.

    PubMed

    Aniza, I; Fairuz, M R

    2009-09-01

    Physical activity is the first line approach and one of the main factors in preventing chronic diseases. Currently there is the increasing percentage of sedentary life style or lack of exercise among adolescents. The main objectives of the study were to determine the prevalence of inactivity and the factors influencing physical activity in adolescents. A cross sectional study was carried out among secondary school students aged 14 and 16 in Petaling District, Selangor, Malaysia. A total of 519 respondents participated in this study. Their physical activity level was measured using the International Physical Activity Questionnaire (IPAQ). The active group was classified as those having levels of equal or more than 600 met-min per week while less than 600 met-min per week was considered inactive. Response rate in this study was 95.4%. The prevalence of inactive in adolescents was 20.8%. Female adolescents, non-working mother, time constraint, exercise only when having ample time and stretching before exercise are predictor factors for being inactive among adolescents. Steps need to be taken to persistently ensure that the physical activity among adolescents be increased continuously.

  18. [Factors Affecting the Dynamics of Circadian Activity of Frit Flies Meromyza saltatrix (L) (Diptera: Chloropidae)].

    PubMed

    Safonkin, A F; Triselyova, T A; Yazchuk, A A; Akent'eva, N A

    2015-01-01

    The dynamics of circadian activity in adult frit flies of the Holarctic species Meromyza saltatrix (L) from Mongolian, Moscow, and Polish populations was studied. Synchronous peaks of activity were revealed with the periodicity multiple of three-four hours, which may depend on the level of light. The direct effect of temperature and humidity on the activity of flies outside the optimal values of these factors was found. It was detected that the peak of adult emergence falls on the beginning of a general increase in the abundance of flies, which indicates constant rejuvenation of the population. The sex ratio is close to 1, but the emergence of males and females is in antiphase. The synchronization of peaks of circadian activity in the populations from different regions confirms the presence of a circadian rhythm of activity. The rhythm synchronizing the reproductive activity of adults was found to be modified by the photoperiod under the optimum conditions of temperature and humidity.

  19. Novel monoclonal antibodies recognizing the active conformation of epidermal growth factor receptor.

    PubMed

    Ise, Nobuyuki; Omi, Kazuya; Miwa, Kyoko; Honda, Hideo; Higashiyama, Shigeki; Goishi, Katsutoshi

    2010-04-09

    The precise regulation of epidermal growth factor receptor (EGFR) is crucial for its function in cellular growth control. Although many antibodies against EGFR have been developed and used to analyze its regulation and function, it is not yet easy to analyze activated EGFR specifically. Activated EGFR has been mainly detected by its phosphorylation state using anti-phospho-EGFR and anti-phosphotyrosine antibodies. In the present study, we have established novel monoclonal antibodies which recognize the activated EGFR independently of its phosphorylation. Our antibodies detected active state of EGFR in immunoprecipitation and immunofluorescence, by recognizing the epitopes which are exposed through the conformational change induced by ligand-binding. Furthermore, we found that our antibodies preferentially detected the conformation of constitutively active EGFR mutants found in lung cancer cell lines. These results indicate that our antibodies may become novel research and diagnostic tools for detecting and analyzing the conformation of active EGFR in various cells and tissues.

  20. Synergistic activation of cells by Epstein-Barr virus and B-cell growth factor.

    PubMed Central

    Hutt-Fletcher, L M

    1987-01-01

    Infection with Epstein-Barr virus (EBV) is initiated by virus binding to the C3dg-C3d receptor CR2. Several workers have implicated this receptor in the control of B-cell activation by examining the effects of antibodies to CR2 and isolated C3d on B-cell proliferation and differentiation. We report here on the activating effects of irradiated EBV, which retains its capacity to bind to CR2 but loses its ability to function as a T-independent B-cell activator. EBV synergized with B-cell growth factor in the induction of uptake of tritiated thymidine by T cell-depleted leukocytes from seronegative donors but did not induce secretion of immunoglobulin. Synergism could be inhibited with an anti-viral antibody that inhibited binding of EBV to CR2. No similar synergism was found between EBV and recombinant interleukin 2, interleukin 1 alpha, or gamma interferon or with the lipid A fraction of bacterial lipopolysaccharide. EBV may thus initiate B-cell activation as it binds to CR2. Infectious virus may, under normal circumstances, induce the cell to make those growth factors necessary to support B-cell proliferation; the difficulty of transforming cells with transfected EBV DNA may in part reflect the absence of an activation event provided by intact virus as it attaches to CR2. The synergism of EBV and B-cell growth factor more clearly distinguishes the effects of B-cell growth factor from those of interleukin 1 and interleukin 2 in other models of B-cell activation. Thus, this may be a useful model for further delineation of unique effects of B-cell growth factor on B-cell function. PMID:3027404

  1. Arginase activity in mitochondria - An interfering factor in nitric oxide synthase activity assays

    SciTech Connect

    Venkatakrishnan, Priya; Nakayasu, Ernesto S.; Almeida, Igor C.; Miller, R.T.

    2010-04-09

    Previously, in tightly controlled studies, using three independent, yet complementary techniques, we refuted the claim that a mitochondrial nitric oxide synthase (mtNOS) isoform exists within pure, rat liver mitochondria (MT). Of those techniques, the NOS-catalyzed [{sup 14}C]-L-arginine to [{sup 14}C]-L-citrulline conversion assay (NOS assay) with MT samples indicated a weak, radioactive signal that was NOS-independent . Aliquots of samples from the NOS assays were then extracted with acetone, separated by high performance thin-layer chromatography (HPTLC) and exposed to autoradiography. Results obtained from these samples showed no radioactive band for L-citrulline. However, a fast-migrating, diffuse, radioactive band was observed in the TLC lanes loaded with MT samples. In this manuscript, we identify and confirm that this radioactive signal in MT samples is due to the arginase-catalyzed conversion of [{sup 14}C]-L-arginine to [{sup 14}C]-urea. The current results, in addition to reconfirming the absence of NOS activity in rat liver MT, also show the need to include arginase inhibitors in studies using MT samples in order to avoid confounding results when using NOS activity assays.

  2. Activation of hypoxia-inducible factor-1; definition of regulatory domains within the alpha subunit.

    PubMed

    Pugh, C W; O'Rourke, J F; Nagao, M; Gleadle, J M; Ratcliffe, P J

    1997-04-25

    Hypoxia-inducible factor-1 (HIF-1), a heterodimeric DNA binding complex composed of two basic-helix-loop-helix Per-AHR-ARNT-Sim proteins (HIF-1alpha and -1beta), is a key component of a widely operative transcriptional response activated by hypoxia, cobaltous ions, and iron chelation. To identify regions of HIF-1 subunits responsible for oxygen-regulated activity, we constructed chimeric genes in which portions of coding sequence from HIF-1 genes were either linked to a heterologous DNA binding domain or encoded between such a DNA binding domain and a constitutive activation domain. Sequences from HIF-1alpha but not HIF-1beta conferred oxygen-regulated activity. Two minimal domains within HIF-1alpha (amino acids 549-582 and amino acids 775-826) were defined by deletional analysis, each of which could act independently to convey inducible responses. Both these regions confer transcriptional activation, and in both cases adjacent sequences appeared functionally repressive in transactivation assays. The inducible operation of the first domain, but not the second, involved major changes in the level of the activator fusion protein in transfected cells, inclusion of this sequence being associated with a marked reduction of expressed protein level in normoxic cells, which was relieved by stimulation with hypoxia, cobaltous ions, or iron chelation. These results lead us to propose a dual mechanism of activation in which the operation of an inducible activation domain is amplified by regulation of transcription factor abundance, most likely occurring through changes in protein stability.

  3. Stem cell factor-mediated activation pathways promote murine eosinophil CCL6 production and survival.

    PubMed

    Dolgachev, Vladislav; Thomas, Molly; Berlin, Aaron; Lukacs, Nicholas W

    2007-04-01

    Eosinophil activation during allergic diseases has a detrimental role in the generation of pathophysiologic responses. Stem cell factor (SCF) has recently shown an inflammatory, gene-activating role on eosinophils and contributes to the generation of pathophysiologic changes in the airways during allergic responses. The data in the present study outline the signal transduction events that are induced by SCF in eosinophils and further demonstrate that MEK-mediated signaling pathways are crucial for SCF-induced CCL6 chemokine activation and eosinophil survival. SCF-mediated eosinophil activation was demonstrated to include PI-3K activation as well as MEK/MAPK phosphorylation pathways. Subsequent analysis of CCL6 gene activation and production induced by SCF in the presence or absence of rather specific inhibitors for certain pathways demonstrated that the MEK/MAPK pathway but not the PI-3K pathway was crucial for the SCF-induced CCL6 gene activation. These same signaling pathways were shown to initiate antiapoptotic events and promote eosinophil survival, including up-regulation of BCL2 and BCL3. Altogether, SCF appears to be a potent eosinophil activation and survival factor.

  4. Glycosylated human oxyhaemoglobin activates nuclear factor-κB and activator protein-1 in cultured human aortic smooth muscle

    PubMed Central

    Peiró, Concepción; Matesanz, Nuria; Nevado, Julián; Lafuente, Nuria; Cercas, Elena; Azcutia, Verónica; Vallejo, Susana; Rodríguez-Mañas, Leocadio; Sánchez-Ferrer, Carlos F

    2003-01-01

    Diabetic vessels undergo structural changes that are linked to a high incidence of cardiovascular diseases. Reactive oxygen species (ROS) mediate cell signalling in the vasculature, where they can promote cell growth and activate redox-regulated transcription factors, like activator protein-1 (AP-1) or nuclear factor-κB (NF-κB), which are involved in remodelling and inflammation processes. Amadori adducts, formed through nonenzymatic glycosylation, can contribute to ROS formation in diabetes. In this study, we analysed whether Amadori-modified human oxyhaemoglobin, glycosylated at either normal (N-Hb) or elevated (E-Hb) levels, can induce cell growth and activate AP-1 and NF-κB in cultured human aortic smooth muscle cells (HASMC). E-Hb (1 nM–1 μM), but not N-Hb, promoted a concentration-dependent increase in cell size from nanomolar concentrations, although it failed to stimulate HASMC proliferation. At 10 nM, E-Hb stimulated both AP-1 and NF-κB activity, as assessed by transient transfection, electromobility shift assays or immunofluorescence staining. The effects of E-Hb resembled those of the proinflammatory cytokine tumour necrosis factor-α (TNF-α). E-Hb enhanced intracellular superoxide anions content and its effects on HASMC were abolished by different ROS scavengers. In conclusion, E-Hb stimulates growth and activates AP-1 and NF-κB in human vascular smooth muscle by redox-sensitive pathways, thus suggesting a possible direct role for Amadori adducts in diabetic vasculopathy. PMID:14504138

  5. Immunocytochemical localization of latent transforming growth factor-beta1 activation by stimulated macrophages

    NASA Technical Reports Server (NTRS)

    Chong, H.; Vodovotz, Y.; Cox, G. W.; Barcellos-Hoff, M. H.; Chatterjee, A. (Principal Investigator)

    1999-01-01

    Transforming growth factor-beta1 (TGF-beta) is secreted in a latent form consisting of mature TGF-beta noncovalently associated with its amino-terminal propeptide, which is called latency associated peptide (LAP). Biological activity depends upon the release of TGF-beta from the latent complex following extracellular activation, which appears to be the key regulatory mechanism controlling TGF-beta action. We have identified two events associated with latent TGF-beta (LTGF-beta) activation in vivo: increased immunoreactivity of certain antibodies that specifically detect TGF-beta concomitant with decreased immunoreactivity of antibodies to LAP. Macrophages stimulated in vitro with interferon-gamma and lipopolysaccharide reportedly activate LTGF-beta via cell membrane-bound protease activity. We show through dual immunostaining of paraformaldehyde-fixed macrophages that such physiological TGF-beta activation is accompanied by a loss of LAP immunoreactivity with concomitant revelation of TGF-beta epitopes. The induction of TGF-beta immunoreactivity colocalized with immunoreactive betaglycan/RIII in activated macrophages, suggesting that LTGF-beta activation occurs on the cell surface. Confocal microscopy of metabolically active macrophages incubated with antibodies to TGF-beta and betaglycan/RIII prior to fixation supported the localization of activation to the cell surface. The ability to specifically detect and localize LTGF-beta activation provides an important tool for studies of its regulation.

  6. Physical activity and dark skin tone: protective factors against low bone mass in Mexican men.

    PubMed

    Vivanco-Muñoz, Nalleli; Jo, Talavera; Gerardo, Huitron-Bravo; Juan, Tamayo; Clark, Patricia

    2012-01-01

    A cross-sectional study was conducted on 268 Mexican men between the ages of 13 and 80 yr to evaluate the association of clinical factors related with bone mass. Men from high schools, universities, and retirement homes were invited to participate. Body mass index (BMI) was measured, and bone mineral density (BMD) was assessed using dual-energy X-ray absorptiometry for L1-L4 and total hip. Factors related to bone mass were assessed by questionnaire and analyzed using a logistic regression model. Demographic factors (age, education, and occupation), clinical data (BMI, skin tone, previous fracture, history of osteoporosis [OP], and history of fractures), and lifestyle variables (diet, physical activity, sun exposure, and smoking) were evaluated. Physical activity (≥ 60 min/5 times a week) reduced the risk for low BMD for age, osteopenia, and OP at the spine and total hip (odds ratio [OR]: 0.276; 95% confidence interval [CI]: 0.099-0.769; p=0.014; and OR: 0.184; 95% CI: 0.04-0.849; p=0.03, respectively). Dark skin tone was a protective factor, decreasing the risk by up to 70%. In this population of healthy Mexican men (aged 13-80 yr), dark skin and physical activity were protective factors against low bone mass.

  7. Targeting Vaccine-Induced Extrafollicular Pathway of B Cell Differentiation Improves Rabies Postexposure Prophylaxis.

    PubMed

    Haley, Shannon L; Tzvetkov, Evgeni P; Meuwissen, Samantha; Plummer, Joseph R; McGettigan, James P

    2017-04-15

    Vaccine-induced B cells differentiate along two pathways. The follicular pathway gives rise to germinal centers (GCs) that can take weeks to fully develop. The extrafollicular pathway gives rise to short-lived plasma cells (PCs) that can rapidly secrete protective antibodies within days of vaccination. Rabies virus (RABV) postexposure prophylaxis (PEP) requires rapid vaccine-induced humoral immunity for protection. Therefore, we hypothesized that targeting extrafollicular B cell responses for activation would improve the speed and magnitude of RABV PEP. To test this hypothesis, we constructed, recovered, and characterized a recombinant RABV-based vaccine expressing murine B cell activating factor (BAFF) (rRABV-mBAFF). BAFF is an ideal molecule to improve early pathways of B cell activation, as it links innate and adaptive immunity, promoting potent B cell responses. Indeed, rRABV-mBAFF induced a faster, higher antibody response in mice and enhanced survivorship in PEP settings compared to rRABV. Interestingly, rRABV-mBAFF and rRABV induced equivalent numbers of GC B cells, suggesting that rRABV-mBAFF augmented the extrafollicular B cell pathway. To confirm that rRABV-mBAFF modulated the extrafollicular pathway, we used a signaling lymphocytic activation molecule (SLAM)-associated protein (SAP)-deficient mouse model. In response to antigen, SAP-deficient mice form extrafollicular B cell responses but do not generate GCs. rRABV-mBAFF induced similar anti-RABV antibody responses in SAP-deficient and wild-type mice, demonstrating that BAFF modulated immunity through the extrafollicular and not the GC B cell pathway. Collectively, strategies that manipulate pathways of B cell activation may facilitate the development of a single-dose RABV vaccine that replaces current complicated and costly RABV PEP.IMPORTANCE Effective RABV PEP is currently resource- and cost-prohibitive in regions of the world where RABV is most prevalent. In order to diminish the requirements for

  8. Structured and Dynamic Disordered Domains Regulate the Activity of a Multifunctional Anti-σ Factor

    PubMed Central

    Herrou, Julien; Willett, Jonathan W.

    2015-01-01

    ABSTRACT The anti-σ factor NepR plays a central role in regulation of the general stress response (GSR) in alphaproteobacteria. This small protein has two known interaction partners: its cognate extracytoplasmic function (ECF) σ factor and the anti-anti-σ factor, PhyR. Stress-dependent phosphorylation of PhyR initiates a protein partner switch that promotes phospho-PhyR binding to NepR, which frees ECF σ to activate transcription of genes required for cell survival under adverse or fluctuating conditions. We have defined key functional roles for structured and intrinsically disordered domains of Caulobacter crescentus NepR in partner binding and activation of GSR transcription. We further demonstrate that NepR strongly stimulates the rate of PhyR phosphorylation in vitro and that this effect requires the structured and disordered domains of NepR. This result provides evidence for an additional layer of GSR regulation in which NepR directly influences activation of its binding partner, PhyR, as an anti-anti-σ factor. We conclude that structured and intrinsically disordered domains of NepR coordinately control multiple functions in the GSR signaling pathway, including core protein partner switch interactions and pathway activation by phosphorylation. PMID:26220965

  9. Adolescents Engaging in Risky Sexual Behavior: Sexual Activity and Associated Behavioral Risk Factors in Bolivian Adolescents

    ERIC Educational Resources Information Center

    Novilla, M. Lelinneth B.; Dearden, Kirk A.; Crookston, Benjamin T.; De La Cruz, Natalie; Hill, Susan; Torres, Scott B.

    2006-01-01

    This study describes the prevalence of risky sexual activities among Bolivian adolescents within the context of other behavioral factors that contribute to compromised health outcomes, unintended pregnancies, and sexually transmitted infections including HIV/AIDS. Data was collected from 576 adolescents, 13-18 years of age, from six schools in La…

  10. Factors Influencing Attitudes toward Sexual Activity among Early Adolescents in Japan

    ERIC Educational Resources Information Center

    Nagamatsu, Miyuki; Yamawaki, Niwako; Sato, Takeshi; Nakagawa, Aki; Saito, Hisako

    2013-01-01

    The purpose of this study was to examine factors influencing attitudes toward sexual activity among early adolescents in Japan. A total of 1,551 students aged 12 to 14 years at 4 junior high schools were divided into either a conservative or liberal group. Results of chi-square tests showed that the liberal group had higher percentages of students…

  11. Increasing Children's Physical Activity: Individual, Social, and Environmental Factors Associated with Walking to and from School

    ERIC Educational Resources Information Center

    Trapp, Georgina S. A.; Giles-Corti, Billie; Christian, Hayley E.; Bulsara, Max; Timperio, Anna F.; McCormack, Gavin R.; Villaneuva, Karen P.

    2012-01-01

    Background. Efforts to increase the prevalence of children's active school transport require evidence to inform the development of comprehensive interventions. This study used a multilevel ecological framework to investigate individual, social, and environmental factors associated with walking to and from school among elementary school-aged…

  12. Parent Perceptions of Factors Influencing After-School Physical Activity of Children with Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Obrusnikova, Iva; Miccinello, Dannielle L.

    2012-01-01

    The study assessed parental perceptions of the benefits of physical activity (PA) and the factors that influence participation of children with autism spectrum disorders in PA after school. Data were collected from 103 parents using an online open-ended questionnaire and focus-group interviews. Data were analyzed using a socioecological model.…

  13. A Comparison of Motivational Factors and Barriers to Physical Activity among Traditional versus Nontraditional College Students

    ERIC Educational Resources Information Center

    Kulavic, Kimberly; Hultquist, Cherilyn N.; McLester, John R.

    2013-01-01

    Objective: To investigate the motivational factors and the barriers to physical activity (PA) in traditional college students (TS) and nontraditional college students (NTS) and determine if differences exist between these 2 groups. Participants: A total of 746 college students; 628 were TS (19.1 [plus-minus] 1.2 years), and 118 were NTS (31.2…

  14. School Administrators' Perceptions of Factors that Influence Children's Active Travel to School

    ERIC Educational Resources Information Center

    Price, Anna E.; Pluto, Delores M.; Ogoussan, Olga; Banda, Jorge A.

    2011-01-01

    Background: Increasing children's active travel to school may be 1 strategy for addressing the growing prevalence of obesity among school age children. Using the School Travel Survey, we examined South Carolina school district leaders' perceptions of factors that influence elementary and middle school students walking to school. Methods: Frequency…

  15. Associations between Physical Activity and Health-Related Factors in a National Sample of College Students

    ERIC Educational Resources Information Center

    Dinger, Mary K.; Brittain, Danielle R.; Hutchinson, Susan R.

    2014-01-01

    Objective: To examine associations between meeting the current moderate to vigorous physical activity (MVPA) recommendation and health-related factors in a national sample of college students. Participants: Participants (N = 67,861) completed the National College Health Assessment II during the Fall 2008/Spring 2009 academic year. Methods:…

  16. Are There Gender-Specific Risk Factors for Suicidal Activity among Patients with Schizophrenia and Depression?

    ERIC Educational Resources Information Center

    Kaplan, Kalman J.; Harrow, Martin; Faull, Robert N.

    2012-01-01

    Are there gender-specific risk factors for suicidal activity among patients with schizophrenia and depression? A total of 74 schizophrenia patients (51 men, 23 women) and 77 unipolar nonpsychotic depressed patients (26 men, 51 women) from the Chicago Follow-up Study were studied prospectively at 2 years posthospitalization and again at 7.5 years.…

  17. The Association between Socio-Ecological Factors and Having an After-School Physical Activity Program

    ERIC Educational Resources Information Center

    Van Acker, Ragnar; De Bourdeaudhuij, Ilse; De Martelaer, Kristine; Seghers, Jan; De Cocker, Katrien; Cardon, Greet

    2012-01-01

    Background: After-school physical activity (PA) programs promote PA among youth. Few studies have used socio-ecological health models to identify barriers and facilitators of after-school PA programs. This study examined which socio-ecological factors are associated with having an after-school PA program. Methods: A questionnaire was administered…

  18. In vivo activity of a nonspecific T cell-replacing factor.

    PubMed

    Kindred, B; Bösing-Schneider, R; Corley, R B

    1979-01-01

    Nonspecific T cell-replacing factors prepared as supernatants from mixed lymphocyte cultures or concanavalin A-stimulated spleen cells are active in vivo iv injected into nude mice at least 3 days before antigen. The supernatants appear to act by enhancing the week IgM responses that occur in untreated nudes. Secondary responses and IgG antibody were not found.

  19. TRANSCRIPTION FACTOR ACTIVATION FOLLOWING EXPOSURE OF AN INTACT LUNG PREPARATION TO METALLIC PARTICULATE MATTER

    EPA Science Inventory

    TRANSCRIPTION FACTOR ACTIVATION FOLLOWING EXPOSURE OF AN INTACT LUNG PREPARATION TO METALLIC PARTICULATE MATTER

    James M. Samet1,2, Robert Silbajoris1, Tony Huang1 and Ilona Jaspers3

    1Human Studies Division, National Health and Environmental Effects Research Laborato...

  20. Safety update on the use of recombinant activated factor VII in approved indications.

    PubMed

    Neufeld, Ellis J; Négrier, Claude; Arkhammar, Per; Benchikh el Fegoun, Soraya; Simonsen, Mette Duelund; Rosholm, Anders; Seremetis, Stephanie

    2015-06-01

    This updated safety review summarises the large body of safety data available on the use of recombinant activated factor VII (rFVIIa) in approved indications: haemophilia with inhibitors, congenital factor VII (FVII) deficiency, acquired haemophilia and Glanzmann's thrombasthenia. Accumulated data up to 31 December 2013 from clinical trials as well as post-marketing data (registries, literature reports and spontaneous reports) were included. Overall, rFVIIa has shown a consistently favourable safety profile, with no unexpected safety concerns, in all approved indications. No confirmed cases of neutralising antibodies against rFVIIa have been reported in patients with congenital haemophilia, acquired haemophilia or Glanzmann's thrombasthenia. The favourable safety profile of rFVIIa can be attributed to the recombinant nature of rFVIIa and its localised mechanism of action at the site of vascular injury. Recombinant FVIIa activates factor X directly on the surface of activated platelets, which are present only at the site of injury, meaning that systemic activation of coagulation is avoided and the risk of thrombotic events (TEs) thus reduced. Nonetheless, close monitoring for signs and symptoms of TE is warranted in all patients treated with any pro-haemostatic agent, including rFVIIa, especially the elderly and any other patients with concomitant conditions and/or predisposing risk factors to thrombosis.

  1. Factors of Participants and Blogs That Predict Blogging Activeness during Teaching Practice and Induction Year

    ERIC Educational Resources Information Center

    Luik, Piret; Taimalu, Merle

    2016-01-01

    The blog as a type of social software has been used in education for several years, and its positive effect in the field has been asserted in many studies. This study presents the factors of participants and blogs that predict blogging activeness during teaching practice and induction year. During the teaching practice and induction year all…

  2. Inflammatory transcription factors as activation markers and functional readouts in immune-to-brain communication.

    PubMed

    Rummel, Christoph

    2016-05-01

    Immune-to-brain communication pathways involve humoral mediators, including cytokines, central modulation by neuronal afferents and immune cell trafficking to the brain. During systemic inflammation these pathways contribute to mediating brain-controlled sickness symptoms including fever. Experimentally, activation of these signaling pathways can be mimicked and studied when injecting animals with pathogen associated molecular patterns (PAMPS). One central component of the brain inflammatory response, which leads, for example, to fever induction, is transcriptional activation of brain cells via cytokines and PAMPS. We and others have studied the spatiotemporal activation and the physiological significance of transcription factors for the induction of inflammation within the brain and the manifestation of fever. Evidence has revealed a role of nuclear factor (NF)κB in the initiation, signal transducer and activator of transcription (STAT)3 in the maintenance and NF-interleukin (IL)6 in the maintenance or even termination of brain-inflammation and fever. Moreover, psychological stressors, such as exposure to a novel environment, leads to increased body core temperature and genomic NF-IL6-activation, suggesting a potential use of NF-IL6-immunohistochemistry as a multimodal brain cell activation marker and a role for NF-IL6 for differential brain activity. In addition, the nutritional status, as reflected by circulating levels of the cytokine-like hormone leptin, influence immune-to-brain communication and age-dependent changes in LPS-induced fever. Overall, transcription factors remain therapeutically important targets for the treatment of brain-inflammation and fever induction during infectious/non-infectious inflammatory and psychological stress. However, the exact physiological role and significance of these transcription factors requires to be further investigated.

  3. Identification and sequence of an accessory factor required for activation of the human interferon gamma receptor.

    PubMed

    Soh, J; Donnelly, R J; Kotenko, S; Mariano, T M; Cook, J R; Wang, N; Emanuel, S; Schwartz, B; Miki, T; Pestka, S

    1994-03-11

    Human chromosomes 6 and 21 are both necessary to confer sensitivity to human interferon gamma (Hu-IFN-gamma), as measured by induction of class I human leukocyte antigen (HLA) and protection against encephalomyocarditis virus (EMCV) infection. Whereas human chromosome 6 encodes the Hu-IFN-gamma receptor, human chromosome 21 encodes accessory factors for generating biological activity through the Hu-IFN-gamma receptor. Probes from a genomic clone were used to identity cDNA clones expressing a species-specific accessory factor. These cDNA clones are able to substitute for human chromosome 21 to reconstitute the Hu-IFN-gamma receptor-mediated induction of class I HLA antigens. However, the factor encoded by the cDNA does not confer full antiviral protection against EMCV, confirming that an additional factor encoded on human chromosome 21 is required for reconstitution of antiviral activity against EMCV. We conclude that this accessory factor belongs to a family of such accessory factors responsible for different actions of IFN-gamma.

  4. Influence of Environmental Factors on the Active Substance Production and Antioxidant Activity in Potentilla fruticosa L. and Its Quality Assessment

    PubMed Central

    Liu, Wei; Yin, Dongxue; Li, Na; Hou, Xiaogai; Wang, Dongmei; Li, Dengwu; Liu, Jianjun

    2016-01-01

    Environmental factors may influence types and contents of active substances. This study investigated the influence of environmental factors on the active substance contents and antioxidant activity of Potentilla fruticosa L. from different regions of China. Also, HPLC fingerprint similarity analysis (SA) coupled with hierarchical cluster analysis (HCA) and discriminant analysis (DA) were further introduced for the accurate classification and quality assessment of P. fruticosa. The results showed that altitude was significantly and negatively correlated to the content of tannin (P < 0.05). Annual sunshine duration and altitude were significantly and positively correlated to the flavonoids content, rutin content and antioxidant activity (P < 0.05). Annual mean temperature was significantly and negatively correlated to the content of total phenolics, while altitude was significantly and positively correlated to the content of total phenolics (P < 0.05). Eight samples were unambiguously separated into three groups. Two types of discriminant functions with a 100% discrimination ratio were constructed. All data consistently supported the conclusion that P. fruticosa produced from Kangding, Sichuan Province had high quality among all samples, therefore, Kangding in Sichuan Province with favorable environmental conditions is recommended as a preferable production location. PMID:27373366

  5. Platelet-activating factor acetylhydrolase deficiency. A missense mutation near the active site of an anti-inflammatory phospholipase.

    PubMed Central

    Stafforini, D M; Satoh, K; Atkinson, D L; Tjoelker, L W; Eberhardt, C; Yoshida, H; Imaizumi, T; Takamatsu, S; Zimmerman, G A; McIntyre, T M; Gray, P W; Prescott, S M

    1996-01-01

    Deficiency of plasma platelet-activating factor (PAF) acetylhydrolase is an autosomal recessive syndrome that has been associated with severe asthma in Japanese children. Acquired deficiency has been described in several human diseases usually associated with severe inflammation. PAF acetylhydrolase catalyzes the degradation of PAF and related phospholipids, which have proinflammatory, allergic, and prothrombotic properties. Thus, a deficiency in the degradation of these lipids should increase the susceptibility to inflammatory and allergic disorders. Miwa et al. reported that PAF acetylhydrolase activity is absent in 4% of the Japanese population, which suggests that it could be a common factor in such disorders, but the molecular basis of the defect is unknown. We show that inherited deficiency of PAF acetylhydrolase is the result of a point mutation in exon 9 and that this mutation completely abolishes enzymatic activity. This mutation is the cause of the lack of enzymatic activity as expression in E. coli of a construct harboring the mutation results in an inactive protein. This mutation as a heterozygous trait is present in 27% in the Japanese population. This finding will allow rapid identification of subjects predisposed to severe asthma and other PAF-mediated disorders. PMID:8675689

  6. Zinc inhibits nuclear factor-kappa B activation and sensitizes prostate cancer cells to cytotoxic agents.

    PubMed

    Uzzo, Robert G; Leavis, Paul; Hatch, William; Gabai, Vladimir L; Dulin, Nickolai; Zvartau, Nadezhda; Kolenko, Vladimir M

    2002-11-01

    Prostate carcinogenesis involves transformation of zinc-accumulating normal epithelial cells to malignant cells, which do not accumulate zinc. In this study, we demonstrate by immunoblotting and immunohistochemistry that physiological levels of zinc inhibit activation of nuclear factor (NF)-kappa B transcription factor in PC-3 and DU-145 human prostate cancer cells, reduce expression of NF-kappa B-controlled antiapoptotic protein c-IAP2, and activate c-Jun NH(2)-terminal kinases. Preincubation of PC-3 cells with physiological concentrations of zinc sensitized tumor cells to tumor necrosis factor (TNF)-alpha, and paclitaxel mediated cell death as defined by terminal deoxynucleotidyl transferase-mediated nick end labeling assay. These results suggest one possible mechanism for the inhibitory effect of zinc on the development and progression of prostate malignancy and might have important consequences for the prevention and treatment of prostate cancer.

  7. Proteolytic properties of single-chain factor XII: a mechanism for triggering contact activation.

    PubMed

    Ivanov, Ivan; Matafonov, Anton; Sun, Mao-Fu; Cheng, Qiufang; Dickeson, S Kent; Verhamme, Ingrid M; Emsley, Jonas; Gailani, David

    2017-03-16

    When blood is exposed to variety of artificial surfaces and biologic substances, the plasma proteins factor XII (FXII) and prekallikrein undergo reciprocal proteolytic conversion to the proteases αFXIIa and α-kallikrein by a process called contact activation. These enzymes contribute to host-defense responses including coagulation, inflammation, and fibrinolysis. The initiating event in contact activation is debated. To test the hypothesis that single-chain FXII expresses activity that could initiate contact activation, we prepared human FXII variants lacking the Arg353 cleavage site required for conversion to αFXIIa (FXII-R353A), or lacking the 3 known cleavage sites at Arg334, Arg343, and Arg353 (FXII-T, for "triple" mutant), and compared their properties to wild-type αFXIIa. In the absence of a surface, FXII-R353A and FXII-T activate prekallikrein and cleave the tripeptide S-2302, demonstrating proteolytic activity. The activity is several orders of magnitude weaker than that of αFXIIa. Polyphosphate, an inducer of contact activation, enhances PK activation by FXII-T, and facilitates FXII-T activation of FXII and FXI. In plasma, FXII-T and FXII-R353A, but not FXII lacking the active site serine residue (FXII-S544A), shortened the clotting time of FXII-deficient plasma and enhanced thrombin generation in a surface-dependent manner. The effect was not as strong as for wild-type FXII. Our results support a model for induction of contact activation in which activity intrinsic to single-chain FXII initiates αFXIIa and α-kallikrein formation on a surface. αFXIIa, with support from α-kallikrein, subsequently accelerates contact activation and is responsible for the full procoagulant activity of FXII.

  8. Hyperin inhibits nuclear factor kappa B and activates nuclear factor E2-related factor-2 signaling pathways in cisplatin-induced acute kidney injury in mice.

    PubMed

    Chao, Chia-Sheng; Tsai, Chien-Sung; Chang, Yee-Phoung; Chen, Jian-Ming; Chin, Hsien-Kuo; Yang, Shyh-Chyun

    2016-11-01

    Hyperin, a flavonoid compound found in Ericaceae, Guttiferae, and Celastraceae, has been reported to have anti-inflammatory effects. In the present study, we investigated the effects of hyperin on cisplatin-induced acute kidney injury (AKI) in mice. The renal tissue damage induced by cisplatin was detected by H&E staining. Blood urea nitrogen (BUN), creatinine, reactive oxygen species (ROS), and malondialdehyde (MDA) were also detected. Further, the effects of hyperin on cisplatin-induced TNF-α, IL-1β and IL-6 were detected by ELISA. In addition, the phosphorylation of nuclear factor kappa B (NF-κB) and the expression of nuclear factor E2-related factor-2 (Nrf2) and HO-1 were detected by western blot analysis. The results showed that hyperin attenuated histological changes of kidney induced by cisplatin. The levels of BUN, creatinine, ROS, MDA, TNF-α, IL-1β and IL-6 induced by cisplatin were also inhibited by hyperin. Cisplatin-induced NF-κB activation was inhibited by hyperin. Additionally, hyperin was found to up regulate the expression of Nrf2 and HO-1. In conclusion, the results suggest that hyperin protects against cisplatin-induced AKI by inhibiting inflammatory and oxidant response.

  9. Environmental factors: opportunities and barriers for physical activity, and healthy eating among children and adolescents.

    PubMed

    Huybrechts, I; De Bourdeaudhuij, I; De Henauw, S

    2010-01-01

    While genetic factors play a role in the development of obesity, the dramatic increase of its prevalence in the past years strongly suggests that environmental factors are largely responsible. The wealth and variety of food supply available 24h/day and throughout the year, the change in dietary habits due to time constraints and the change in physical activity due to technological advances all create a 'toxic' environment responsible for obesity and eating habit disorders. This manuscript describes and discusses the results of a systematic review of environmental opportunities & obstacles for physical activity and dietary intake influencing the obesity epidemic among children and adolescents. Although evidence clearly shows the impact of the environment on obesity related lifestyle factors, evidence for effective strategies combating this obesogenic environment is very scarce. Interventions aiming to change environmental factors in order to reduce obesity may include taxes/subsidies encouraging healthy eating or physical activity, extra provision of sporting facilities, efforts to improve safety and accessibility of walking, cycling or play areas or attempting to influence social meanings/values attached to weight, food or physical activity. It is clear that some level of institutionalization of systems that support the desired changes is required to sustain environmental and social changes in the long-term. At last, it is important to note that better-designed and -conducted research on the true importance of the interaction between environmental factors and psychosocial factors, including the micro- and the macro-level, for obesogenic behavioral change is needed to reassure the success of large-scale environmental change interventions.

  10. Elective surgery on factor VIII inhibitor patients using continuous infusion of recombinant activated factor VII: plasma factor VII activity of 10 IU/ml is associated with an increased incidence of bleeding.

    PubMed

    Smith, M P; Ludlam, C A; Collins, P W; Hay, C R; Wilde, J T; Grigeri, A; Melsen, T; Savidge, G F

    2001-10-01

    We examined recombinant activated factor VII (rVIIa) administered by continuous infusion to eight patients with inhibitors to factor VIII, undergoing elective surgery. rVIIa was infused at a fixed rate of 16.5 microg/kg/h for a median of 13.5 days (range 1-26). There was effective haemostasis at this infusion rate in only one of two minor procedures and two of six major operations. Three patients experienced excessive bleeding despite plasma factor VII activity around 10 IU/ml. Serious bleeding occurred in two other patients caused by procedural errors unrelated to rVIIa and required re-operation. The median rVIIa clearance on day 1 was 57 ml/h/kg (range 18-100) and on day 3 was 100 ml/h/kg (range 61-200). Clearance on the final infusion day was not significantly different from day 3. The infusion did not induce pathological activation of the coagulation mechanism. The only thrombotic adverse events were two episodes of superficial thrombophlebitis of the infused vein in one subject. In conclusion, the 16.5 microg/kg/h infusion rate reliably achieves plasma factor VII activity levels of 10 IU/ml, but this level does not provide reliable haemostasis.

  11. Development of scaling factors for the activated concrete of the KRR-2.

    PubMed

    Hong, Sang-Bum; Kang, Mun-Ja; Lee, Ki-Won; Chung, Un-Soo

    2009-01-01

    The biological shielding concrete of KRR-2 was activated by a thermal neutron reaction during the operation of the reactor, thus a variety of radionuclides were generated in the concrete. In order to verify the radioactivity for the final disposal of waste and to achieve a more efficient cutting of the concrete, the radioactivity inventories and distributions of the activated concrete were evaluated. The activity of gamma-emitting radionuclides was measured by using an HPGe detector. The beta-emitting radionuclides were measured by an oxidation/combustion method for (3)H and (14)C and a combined method of an extraction chromatography and a liquid scintillation for (55)Fe and (63)Ni. The dominant radioactive nuclides in the activated concrete were (3)H, (14)C, (55)Fe and (60)Co, and the maximum gamma activity was 105Bq/g at the surface around the thermal column. The specific activities of all the nuclides were found to decrease almost linearly on a logarithmic scale along the depth from the inner surface of the concrete. Equations for scaling factors were obtained by a linear regression of logarithms from the radioactivity data of (3)H/(60)Co, (14)C/(60)Co and (55)Fe/(60)Co nuclide pairs of the activated concrete. The scaling factors can be utilized for the estimation of beta radioactivity without the time consuming separation processes of the nuclides.

  12. Characterization of a platelet-activating factor acetylhydrolase secreted by the nematode parasite Nippostrongylus brasiliensis.

    PubMed Central

    Grigg, M E; Gounaris, K; Selkirk, M E

    1996-01-01

    Nippostrongylus brasiliensis, a small nematode parasite of the gastrointestinal tract of rodents, secretes an enzyme that cleaves the proinflammatory molecule platelet-activating factor to its inactive lyso-form. The enzyme activity of Ca(2+)-dependent and does not exhibit interfacial activation. It does not require the addition of reducing agents for maximal activity, and is not inhibited by thiol-active reagents. Sensitivity of inhibitors suggests the involvement of serine and histidine residues in the enzyme activity. As described for other platelet-activating factor acetylhydrolases, it cannot cleave, nor is it inhibited by, long-chain diacyl phospholipids that are typical substrates for phospholipases A2. The purified enzyme was resolved by SDS/PAGE as a heterodimer composed of two protein subunits with apparent molecular masses of 38 and 25 kDa. The properties of the nematode enzyme thus differ from those described for the mammalian enzymes, but are more closely related to those of an acetylhydrolase than a phospholipase. PMID:8713083

  13. The EDLL motif: a potent plant transcriptional activation domain from AP2/ERF transcription factors.

    PubMed

    Tiwari, Shiv B; Belachew, Alemu; Ma, Siu Fong; Young, Melinda; Ade, Jules; Shen, Yu; Marion, Colleen M; Holtan, Hans E; Bailey, Adina; Stone, Jeffrey K; Edwards, Leslie; Wallace, Andreah D; Canales, Roger D; Adam, Luc; Ratcliffe, Oliver J; Repetti, Peter P

    2012-06-01

    In plants, the ERF/EREBP family of transcriptional regulators plays a key role in adaptation to various biotic and abiotic stresses. These proteins contain a conserved AP2 DNA-binding domain and several uncharacterized motifs. Here, we describe a short motif, termed 'EDLL', that is present in AtERF98/TDR1 and other clade members from the same AP2 sub-family. We show that the EDLL motif, which has a unique arrangement of acidic amino acids and hydrophobic leucines, functions as a strong activation domain. The motif is transferable to other proteins, and is active at both proximal and distal positions of target promoters. As such, the EDLL motif is able to partly overcome the repression conferred by the AtHB2 transcription factor, which contains an ERF-associated amphiphilic repression (EAR) motif. We further examined the activation potential of EDLL by analysis of the regulation of flowering time by NF-Y (nuclear factor Y) proteins. Genetic evidence indicates that NF-Y protein complexes potentiate the action of CONSTANS in regulation of flowering in Arabidopsis; we show that the transcriptional activation function of CONSTANS can be substituted by direct fusion of the EDLL activation motif to NF-YB subunits. The EDLL motif represents a potent plant activation domain that can be used as a tool to confer transcriptional activation potential to heterologous DNA-binding proteins.

  14. MiT/TFE transcription factors are activated during mitophagy downstream of Parkin and Atg5

    PubMed Central

    Nezich, Catherine L.; Wang, Chunxin; Fogel, Adam I.

    2015-01-01

    The kinase PINK1 and ubiquitin ligase Parkin can regulate the selective elimination of damaged mitochondria through autophagy (mitophagy). Because of the demand on lysosomal function by mitophagy, we investigated a role for the transcription factor EB (TFEB), a master regulator of lysosomal biogenesis, in this process. We show that during mitophagy TFEB translocates to the nucleus and displays transcriptional activity in a PINK1- and Parkin-dependent manner. MITF and TFE3, homologues of TFEB belonging to the same microphthalmia/transcription factor E (MiT/TFE) family, are similarly regulated during mitophagy. Unlike TFEB translocation after starvation-induced mammalian target of rapamycin complex 1 inhibition, Parkin-mediated TFEB relocalization required Atg9A and Atg5 activity. However, constitutively active Rag guanosine triphosphatases prevented TFEB translocation during mitophagy, suggesting cross talk between these two MiT/TFE activation pathways. Analysis of clustered regularly interspaced short palindromic repeats–generated TFEB/MITF/TFE3/TFEC single, double, and triple knockout cell lines revealed that these proteins partly facilitate Parkin-mediated mitochondrial clearance. These results illuminate a pathway leading to MiT/TFE transcription factor activation, distinct from starvation-induced autophagy, which occurs during mitophagy. PMID:26240184

  15. The evidence of production or activation of a natriuretic factor in the liver.

    PubMed

    Ivanov, Y I

    1979-01-01

    The natriuretic activity was measured with the aid of bioassay in blood flowing out from the brain, kidney and liver before and after the expansion of extracellular space in dogs. In another experiments in rats the volume natriuresis and the natriuretic activity in blood were measured in controls and in animals with carbon tetrachloride liver dystrophy and pharmacological stimulation (dehydrocholic acid, Ca pantothenate, cyanocobalamin) of liver functions. In dogs, the level of natriuretic activity in blood flowing out of the liver before and after the expansion of extracellular fluid volume was significantly higher than that in arterial blood. In contrast, the natriuretic activity was not found in the blood flowing out of the brain and the kidney. In rats the experimental dystrophy of the liver decreased the content of a natriuretic factor in blood plasma and the expansion of extracellular space did not produce any natriuretic effect as compared to control rats. After pharmacological stimulation of the liver by dehydrocholic acid, Ca pantothenate and cyanocobalamine the volume expansion led to a significant increase of the excretion of sodium by the kidney and to the increase of the content of a natriuretic factor in blood plasma as compared to control rats. These facts are considered to support the view that a natriuretic factor is either synthesized or activated by the liver.

  16. Individual factors affecting preferences for feedback message tactics in the contexts of physical activity.

    PubMed

    Hirvonen, Noora; Enwald, Heidi; Bath, Peter A; Pyky, Riitta; Korpelainen, Raija; Huotari, Maija-Leena

    2015-01-01

    Tailored feedback on personal physical activity behavior has been used to inform individuals and promote physical activity among different populations. This study aimed to increase the understanding of factors associated with young men's preferences for feedback message tactics in the context of physical activity and exercise. How preferences vary was analyzed in terms of the self-reported physical activity, stage of exercise behavior change, exercise self-efficacy, objectively measured physical health status, and sociodemographic characteristics of young Finnish men. Population-based survey data, including physiological measurements (n = 525), were collected at the Finnish Defence Forces' call-ups in the city of Oulu, Finland, in September 2011. The results indicate that the stage of exercise behavior change, exercise self-efficacy, physical health status, and educational level are associated with a preference for normative and ipsative comparison. Multivariate logistic regression models show that an advanced stage of exercise behavior change and education in the academic track of an upper secondary school are independent predictors of preferring ipsative and normative physical activity feedback among young men. The study provides new insights into how the stage of behavior change influences health information behavior and is in line with studies emphasizing social factors--including education--as being important in shaping health-related behavior. These factors could form the basis for tailoring information when designing health promotion.

  17. Enhancement of RNA Polymerase Activity by a Factor Released by Auxin from Plasma Membrane*

    PubMed Central

    Hardin, James W.; Cherry, Joe H.; Morré, D. James; Lembi, Carole A.

    1972-01-01

    Using recently developed techniques for solubilization of RNA polymerase from soybean chromatin and isolation of plasma membrane fractions from plants we can show the presence of a transcriptional factor specifically released from the membranes by auxin, 2,4-dichlorophenoxyacetic acid. The nonauxin, 3,5-dichlorophenoxyacetic acid, does not release the factor, but subsequent exposure of the membranes to auxin results in its release. Factor activity could not be demonstrated in fractions devoid of plasma membranes. The presence of a regulatory factor for RNA polymerase associated with plant plasma membrane and specifically released by auxin provides a mechanism whereby both rapid growth responses and delayed nuclear changes could be derived from a common auxin receptor site associated with plasma membrane. Images PMID:4508307

  18. Passive-submissive and active-emotional trait dependency: evidence for a two-factor model.

    PubMed

    Morgan, Theresa A; Clark, Lee Anna

    2010-08-01

    Dependency plays an important role in both normal and abnormal personality, but the construct remains loosely defined, both in clinical practice and the research literature. Moreover, although a number of measures purport to measure trait dependency, little agreement exists as to the structure of dependency within or across these instruments. Furthermore, what constitutes the low end of trait dependency remains unclear. Five hundred nine undergraduates completed a battery of 14 dependency scales and subscales, a subset of whom (n=322) also completed a broad measure of personality pathology (SNAP-2). Exploratory factor analysis of the dependency measures yielded two correlated factors-Passive-Submissive and Active-Emotional dependency-as well as a third, unrelated factor, Detachment/Autonomy, all with differential correlates to the pathological personality traits of the SNAP-2. Taken together, these data suggest a clear, 2-factor model for trait dependency that is distinct from detachment/autonomy.

  19. Platelet-derived growth factor (PDGF) stimulates glycogen synthase activity in 3T3 cells

    SciTech Connect

    Chan, C.P.; Bowen-Pope, D.F.; Ross, R.; Krebs, E.G.

    1986-05-01

    Hormonal regulation of glycogen synthase, an enzyme that can be phosphorylated on multiple sites, is often associated with changes in its phosphorylation state. Enzyme activation is conventionally monitored by determining the synthase activity ratio ((activity in the absence of glucose 6-P)/(activity in the presence of glucose 6-P)). Insulin causes an activation of glycogen synthase with a concomitant decrease in its phosphate content. In a previous report, the authors showed that epidermal growth factor (EGF) increases the glycogen synthase activity ratio in Swiss 3T3 cells. The time and dose-dependency of this response was similar to that of insulin. Their recent results indicate that PDGF also stimulates glycogen synthase activity. Enzyme activation was maximal after 30 min. of incubation with PDGF; the time course observed was very similar to that with insulin and EGF. At 1 ng/ml (0.03nM), PDGF caused a maximal stimulation of 4-fold in synthase activity ratio. Half-maximal stimulation was observed at 0.2 ng/ml (6 pM). The time course of changes in enzyme activity ratio closely followed that of /sup 125/I-PDGF binding. The authors data suggest that PDGF, as well as EFG and insulin, may be important in regulating glycogen synthesis through phosphorylation/dephosphorylation mechanisms.

  20. Transgenic songbirds with suppressed or enhanced activity of CREB transcription factor

    PubMed Central

    Abe, Kentaro; Matsui, Sumiko; Watanabe, Dai

    2015-01-01

    Songbirds postnatally develop their skill to utter and to perceive a vocal signal for communication. How genetic and environmental influences act in concert to regulate the development of such skill is not fully understood. Here, we report the phenotype of transgenic songbirds with altered intrinsic activity of cAMP response element-binding protein (CREB) transcription factor. By viral vector-mediated modification of genomic DNA, we established germ line-transmitted lines of zebra finches, which exhibited enhanced or suppressed activity of CREB. Although intrinsically acquired vocalizations or their hearing ability were not affected, the transgenic birds showed reduced vocal learning quality of their own songs and impaired audio-memory formation against conspecific songs. These results thus demonstrate that appropriate activity of CREB is necessary for the postnatal acquisition of learned behavior in songbirds, and the CREB transgenic birds offer a unique opportunity to separately manipulate both genetic and environmental factors that impinge on the postnatal song learning. PMID:26048905

  1. Changes in nonnutritional factors and antioxidant activity during germination of nonconventional legumes.

    PubMed

    Aguilera, Yolanda; Díaz, María Felicia; Jiménez, Tania; Benítez, Vanesa; Herrera, Teresa; Cuadrado, Carmen; Martín-Pedrosa, Mercedes; Martín-Cabrejas, María A

    2013-08-28

    The present study describes the effects of germination on nonnutritional factors and antioxidant activity in the nonconventional legumes Vigna unguiculata (cowpea), Canavalia ensiformis (jack bean), Lablab purpureus (dolichos), and Stizolobium niveum (mucuna). Protease inhibitors and lectins were detected in raw legumes and were significantly decreased during the germination. Regarding total and individual inositol phosphates (IP5-IP3), important reductions of IP6 and high increases in the rest of inositol phosphates were also detected during this process. In addition, total phenols, catechins, and proanthocyanidins increased, accompanied by an overall rise of antioxidant activity (79.6 μmol of Trolox/g of DW in the case of mucuna). Germination has been shown to be a very effective process to reduce nonnutritional factors and increase bioactive phenolic compounds and antioxidant activities of these nonconventional legumes. For this reason, they could be used as ingredients to obtain high-value legume flours for food formulation.

  2. Gene deregulation and chronic activation in natural killer cells deficient in the transcription factor ETS1.

    PubMed

    Ramirez, Kevin; Chandler, Katherine J; Spaulding, Christina; Zandi, Sasan; Sigvardsson, Mikael; Graves, Barbara J; Kee, Barbara L

    2012-06-29

    Multiple transcription factors guide the development of mature functional natural killer (NK) cells, yet little is known about their function. We used global gene expression and genome-wide binding analyses combined with developmental and functional studies to unveil three roles for the ETS1 transcription factor in NK cells. ETS1 functions at the earliest stages of NK cell development to promote expression of critical transcriptional regulators including T-BET and ID2, NK cell receptors (NKRs) including NKp46, Ly49H, and Ly49D, and signaling molecules essential for NKR function. As a consequence, Ets1(-/-) NK cells fail to degranulate after stimulation through activating NKRs. Nonetheless, these cells are hyperresponsive to cytokines and have characteristics of chronic stimulation including increased expression of inhibitory NKRs and multiple activation-associated genes. Therefore, ETS1 regulates a broad gene expression program in NK cells that promotes target cell recognition while limiting cytokine-driven activation.

  3. C/EBP Transcription Factors Mediate Epicardial Activation During Heart Development and Injury

    PubMed Central

    Huang, Guo N.; Thatcher, Jeffrey E.; McAnally, John; Kong, Yongli; Qi, Xiaoxia; Tan, Wei; DiMaio, J. Michael; Amatruda, James F.; Gerard, Robert D.; Hill, Joseph A.; Bassel-Duby, Rhonda; Olson, Eric N.

    2013-01-01

    The epicardium encapsulates the heart and functions as a source of multipotent progenitor cells and paracrine factors essential for cardiac development and repair. Injury of the adult heart results in reactivation of a developmental gene program in the epicardium, but the transcriptional basis of epicardial gene expression has not been delineated. We established a mouse embryonic heart organ culture and gene expression system that facilitated the identification of epicardial enhancers activated during heart development and injury. Epicardial activation of these enhancers depends on a combinatorial transcriptional code centered on CCAAT/enhancer binding protein (C/EBP) transcription factors. Disruption of C/EBP signaling in the adult epicardium reduced injury-induced neutrophil infiltration and improved cardiac function. These findings reveal a transcriptional basis for epicardial activation and heart injury, providing a platform for enhancing cardiac regeneration. PMID:23160954

  4. Interferon and tumor necrosis factor as humoral mechanisms coupling hematopoietic activity to inflammation and injury.

    PubMed

    Askenasy, Nadir

    2015-01-01

    Enhanced hematopoiesis accompanies systemic responses to injury and infection. Tumor necrosis factor (TNF) produced by injured cells and interferons (IFNs) secreted by inflammatory cells is a co-product of the process of clearance of debris and removal of still viable but dysfunctional cells. Concomitantly, these cytokines induce hematopoietic stem and progenitor cell (HSPC) activity as an intrinsic component of the systemic response. The proposed scenario includes induction of HSPC activity by type I (IFNα/β) and II (IFNγ) receptors within the quiescent bone marrow niches rendering progenitors responsive to additional signals. TNFα converges as a non-selective stimulant of HSPC activity and both cytokines synergize with other growth factors in promoting differentiation. These physiological signaling pathways of stress hematopoiesis occur quite frequent and do not cause HSPC extinction. The proposed role of IFNs and TNFs in stress hematopoiesis commends revision of their alleged involvement in bone marrow failure syndromes.

  5. Changing Factors associated with Parent Activation after Pediatric Hematopoietic Stem Cell Transplant

    PubMed Central

    Pennarola, Brian W.; Rodday, Angie Mae; Bingen, Kristin; Schwartz, Lisa A.; Patel, Sunita K.; Syrjala, Karen L.; Mayer, Deborah K.; Ratichek, Sara J.; Guinan, Eva C.; Kupst, Mary Jo; Hibbard, Judith H.; Parsons, Susan K.

    2015-01-01

    Purpose To identify factors associated with parent activation in parents of children undergoing pediatric hematopoietic stem cell transplant (HSCT) in the 6 months following HSCT, and to address if their association with parent activation changes over time. Methods Measures for this analysis, including the Parent Patient Activation Measure (Parent-PAM), were completed by parents (N=198) prior to their child’s HSCT preparative regimen and again at 6 months post-HSCT. Clinical data were also collected. A repeated measures model was built to estimate the association between clinical and demographic factors and parent well-being on Parent-PAM scores. Interactions with time were considered to test for changing effects over time. Results Throughout the HSCT course, older parent age was associated with lower Parent-PAM scores (β=−0.29, p=0.02) and never being married was associated with higher scores (versus married, β=12.27, p=0.03). While higher parent emotional functioning scores were not associated with activation at baseline, they were important at 6 months (baseline: β=−0.002, p=0.96; interaction: β=0.14, p=0.03). At baseline longer duration of illness was associated with increased activation, but this effect diminished with time (baseline: β=3.29, p=0.0002; interaction: β=−2.40, p=0.02). Activation levels dropped for parents of children who went from private to public insurance (baseline: β=2.95, p=0.53; interaction: β=−13.82, p=0.004). Clinical events did not affect Parent-PAM scores. Conclusions Our findings reveal important changes in the factors associated with parent activation in the first 6 months after pediatric HSCT. These findings may reflect the emotional and financial toll of pediatric HSCT on parent activation. PMID:25519755

  6. Transcriptional Activation Domains of Human Heat Shock Factor 1 Recruit Human SWI/SNF

    PubMed Central

    Sullivan, E. Kelly; Weirich, Christine S.; Guyon, Jeffrey R.; Sif, Saïd; Kingston, Robert E.

    2001-01-01

    Chromatin remodeling complexes such as SWI/SNF use the energy of ATP hydrolysis to remodel nucleosomal DNA and increase transcription of nucleosomal templates. Human heat shock factor one (hHSF1) is a tightly regulated activator that stimulates transcriptional initiation and elongation using different portions of its activation domains. Here we demonstrate that hHSF1 associates with BRG1, the ATPase subunit of human SWI/SNF (hSWI/SNF) at endogenous protein concentrations. We also show that hHSF1 activation domains recruit hSWI/SNF to a chromatin template in a purified system. Mutation of hHSF1 residues responsible for activation of transcriptional elongation has the most severe effect on recruitment of SWI/SNF and association of hHSF1 with BRG1, suggesting that recruitment of chromatin remodeling activity might play a role in stimulation of elongation. PMID:11486022

  7. Factors That Moderate Activity Limitation and Participation Restriction in People With Multiple Sclerosis.

    PubMed

    Goverover, Yael; Strober, Lauren; Chiaravalloti, Nancy; DeLuca, John

    2015-01-01

    We examined the variables most associated with activity limitation (i.e., cooking) and participation restriction (i.e., employment) in 72 people with multiple sclerosis (MS). Participants underwent a comprehensive neuropsychological test battery assessing memory, executive functions, visual perception, and processing speed and completed questionnaires assessing activity, participation, fatigue, and affective symptoms. Results showed that processing speed was the only variable consistently significantly related to both activity and participation. When examining specific aspects of activity and participation in isolation, employment status was significantly associated with education level, visual memory, fatigue, and processing speed. Cooking ability was associated with performance on tasks of working memory, verbal memory, and processing speed. These findings suggest that processing speed is a primary cognitive factor in MS influencing quality of both activity and participation in everyday life.

  8. Factor C acts as a lipopolysaccharide-responsive C3 convertase in horseshoe crab complement activation.

    PubMed

    Ariki, Shigeru; Takahara, Shusaku; Shibata, Toshio; Fukuoka, Takaaki; Ozaki, Aya; Endo, Yuichi; Fujita, Teizo; Koshiba, Takumi; Kawabata, Shun-ichiro

    2008-12-01

    The complement system in vertebrates plays an important role in host defense against and clearance of invading microbes, in which complement component C3 plays an essential role in the opsonization of pathogens, whereas the molecular mechanism underlying C3 activation in invertebrates remains unknown. In an effort to understand the molecular activation mechanism of invertebrate C3, we isolated and characterized an ortholog of C3 (designated TtC3) from the horseshoe crab Tachypleus tridentatus. Flow cytometric analysis using an Ab against TtC3 revealed that the horseshoe crab complement system opsonizes both Gram-negative and Gram-positive bacteria. Evaluation of the ability of various pathogen-associated molecular patterns to promote the proteolytic conversion of TtC3 to TtC3b in hemocyanin-depleted plasma indicated that LPS, but not zymosan, peptidoglycan, or laminarin, strongly induces this conversion, highlighting the selective response of the complement system to LPS stimulation. Although originally characterized as an LPS-sensitive initiator of hemolymph coagulation stored within hemocytes, we identified factor C in hemolymph plasma. An anti-factor C Ab inhibited various LPS-induced phenomena, including plasma amidase activity, the proteolytic activation of TtC3, and the deposition of TtC3b on the surface of Gram-negative bacteria. Moreover, activated factor C present on the surface of Gram-negative bacteria directly catalyzed the proteolytic conversion of the purified TtC3, thereby promoting TtC3b deposition. We conclude that factor C acts as an LPS-responsive C3 convertase on the surface of invading Gram-negative bacteria in the initial phase of horseshoe crab complement activation.

  9. PGE2 is a UVR-inducible autocrine factor for human melanocytes that stimulates tyrosinase activation

    PubMed Central

    Starner, Renny J.; McClelland, Lindy; Abdel-Malek, Zalfa; Fricke, Alex; Scott, Glynis

    2013-01-01

    Melanocyte proliferation, dendrite formation, and pigmentation are controlled by paracrine factors, particularly following exposure to ultraviolet radiation (UVR). Little is known about autocrine factors for melanocytes. Prostaglandins activate signaling pathways involved in growth, differentiation and apoptosis. Prostaglandin E2 (PGE2) is the most abundant prostaglandin released by keratinocytes following UVR, and stimulates the formation of dendrites in melanocytes. Synthesis of PGE2 is controlled by cPLA2, which releases arachidonic acid from membranes, and COX-2 and prostaglandin E2 synthases (PGES), which convert arachidonic acid to PGH2 and PGH2 to PGE2, respectively. In this report we show that multiple irradiations of human melanocytes with UVR stimulates tyrosinase activity, independent of expression of a functional melanocortin 1 receptor, suggesting the presence of a non-melanocortin autocrine factor. Irradiation of melanocytes activated cPLA2, the rate-limiting step in eicosanoid synthesis, and stimulated PGE2 secretion. PGE2 increased cAMP production, tyrosinase activity and proliferation in melanocytes. PGE2 binds to four distinct G-protein coupled receptors (EP1–4). We show that EP4 receptor signaling stimulates cAMP production in melanocytes. Conversely, stimulation of the EP3 receptor lowered basal cAMP levels. These data suggest that relative levels or activity of these receptors controls effects of PGE2 on cAMP in melanocytes. The data are the first to identify PGE2 as an UVR-inducible autocrine factor for melanocytes that stimulates tyrosinase activity and proliferation, and to show that EP3 and EP4 receptor signaling have opposing effects on cAMP production, a critical signaling pathway that regulates proliferation and melanogenesis in melanocytes. PMID:20500768

  10. On involvement of transcription factors nuclear factor kappa-light-chain-enhancer of activated B cells, activator protein-1 and signal transducer and activator of transcription-3 in photodynamic therapy-induced death of crayfish neurons and satellite glial cells

    NASA Astrophysics Data System (ADS)

    Berezhnaya, Elena; Neginskaya, Marya; Kovaleva, Vera; Sharifulina, Svetlana; Ischenko, Irina; Komandirov, Maxim; Rudkovskii, Mikhail; Uzdensky, Anatoly B.

    2015-07-01

    Photodynamic therapy (PDT) is currently used in the treatment of brain tumors. However, not only malignant cells but also neighboring normal neurons and glial cells are damaged during PDT. In order to study the potential role of transcription factors-nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), activator protein (AP-1), and signal transducer and activator of transcription-3 (STAT-3)-in photodynamic injury of normal neurons and glia, we photosensitized the isolated crayfish mechanoreceptor consisting of a single sensory neuron enveloped by glial cells. Application of different inhibitors and activators showed that transcription factors NF-κB (inhibitors caffeic acid phenethyl ester and parthenolide, activator betulinic acid), AP-1 (inhibitor SR11302), and STAT-3 (inhibitors stattic and cucurbitacine) influenced PDT-induced death and survival of neurons and glial cells in different ways. These experiments indicated involvement of NF-κB in PDT-induced necrosis of neurons and apoptosis of glial cells. However, in glial cells, it played the antinecrotic role. AP-1 was not involved in PDT-induced necrosis of neurons and glia, but mediated glial apoptosis. STAT-3 was involved in PDT-induced apoptosis of glial cells and necrosis of neurons and glia. Therefore, signaling pathways that regulate cell death and survival in neurons and glial cells are different. Using various inhibitors or activators of transcription factors, one can differently influence the sensitivity and resistance of neurons and glial cells to PDT.

  11. Adherence to Physical Activity Recommendations and Its Associated Factors: An Interregional Population-Based Study

    PubMed Central

    Alkerwi, Ala’a; Schuh, Barbara; Sauvageot, Nicolas; Zannad, Faiez; Olivier, Arnaud; Guillaume, Michèle; Albert, Adelin; Larsson, Charlotte A.

    2015-01-01

    Background Though the influence of physical activity in preventing cardiovascular diseases is well documented, only a few comparative studies have determined the degree of adherence to physical activity recommendations among populations and identified the demographic, socioeco-nomic, behavioural and health-related factors associated with good compliance. Design and methods Cross-sectional interregional NESCaV survey of 3133 subjects compared three populations, Luxembourg, Lorraine (France) and Wallonia (Belgium), by using the International Physical Activity Questionnaire. Age and gender prevalence rates of physical activity were standardized to the European population. Results The likelihood to meet the recommendations was higher in Luxembourg, after adjustment for age, gender, education, employment, weight status, morbidity score, health perception and level of importance attributed to the practice of physical activity (P<0.0001). The odds for meeting the recommendations were significantly higher among those with secondary than tertiary education. Compared to good self-health perception, subjects with poor or fair self-perceived health were less likely to meet the recommendations; this also applied to those attributing little or enough importance to physical activity compared with great importance. Conclusions Region, education, self-perceived health and perception of importance of physical activity were emerged as independent determinants of meeting the recommendations. Awareness of the positive health effects of physical activity might thus be crucial for motivating the people to become more active. Further research is needed to explore potential region-specific factors which might explain the difference in population behaviours with respect to physical activity. Significance for public health This manuscript describes the prevalence of physical activity level of adult population from three European regions, Luxembourg, Wallonia and Lorraine, based on the

  12. Suppression of tumor necrosis factor-α-induced nuclear factor κB activation and aromatase activity by capsaicin and its analog capsazepine.

    PubMed

    Luqman, Suaib; Meena, Abha; Marler, Laura E; Kondratyuk, Tamara P; Pezzuto, John M

    2011-11-01

    Target-specific drugs, including natural products, offer promise for the amelioration of cancer and other human ailments. Capsaicin, the pungent ingredient present in chilies (Capsicum annuum L.), and capsazepine, a synthetic analog of capsaicin (collectively referred to as vanilloids), are known to possess a variety of pharmacological and physiological properties. In our continuous effort to discover and characterize cancer chemopreventive agents from natural products, we investigated the effect of vanilloids on nuclear factor κ-light-chain-enhancer of activated B cells (NFκB) activation using stably transfected 293/NFκB-Luc human embryonic kidney cells induced by treatment with tumor necrosis factor-α (TNFα) and on aromatase activity. Capsaicin and capsazepine blocked TNFα-induced NFκB activation in a dose-dependent manner with 50% inhibitory concentration (IC(50)) values of 0.68 and 4.2 μM, respectively. No significant cytotoxicity was observed at the highest concentrations tested (53.1 μM for capsazepine and 65.5 μM for capsaicin). In addition, these vanilloids inhibited aromatase activity with IC(50) values of 13.6 and 8.8 μM, respectively. Computer-aided molecular docking studies showed docking scores indicative of good binding affinity of vanilloids with aromatase and NFκB. The highly conserved residues for capsaicin and capsazepine binding with NFκB p50 were Ser299 and Ile278 (H-bond 2.81Å) and with NFκB p100 were Ser6, Arg82, Val86, Arg90 (H-bond 2.89Å), Gly4, and Ser2 (H-bond 2.81Å). The amino acids Trp224, Arg435, and Val373 (H-bond 2.80Å) were found to be important for the binding of capsaicin and capsazepine with aromatase. Based on these findings, aromatase and NFκB are suggested as valid targets for these compounds; additional investigation of chemopreventive or chemotherapeutic potential is required.

  13. Factors Influencing the Measurement of Lysosomal Enzymes Activity in Human Cerebrospinal Fluid

    PubMed Central

    Parnetti, Lucilla; Eusebi, Paolo; Paciotti, Silvia; De Carlo, Claudia; Codini, Michela; Tambasco, Nicola; Rossi, Aroldo; Agnaf, Omar M. El.; Calabresi, Paolo; Beccari, Tommaso

    2014-01-01

    Measurements of the activities of lysosomal enzymes in cerebrospinal fluid have recently been proposed as putative biomarkers for Parkinson's disease and other synucleinopathies. To define the operating procedures useful for ensuring the reliability of these measurements, we analyzed several pre-analytical factors that may influence the activity of β-glucocerebrosidase, α-mannosidase, β-mannosidase, β-galactosidase, α-fucosidase, β-hexosaminidase, cathepsin D and cathepsin E in cerebrospinal fluid. Lysosomal enzyme activities were measured by well-established fluorimetric assays in a consecutive series of patients (n = 28) with different neurological conditions, including Parkinson's disease. The precision, pre-storage and storage conditions, and freeze/thaw cycles were evaluated. All of the assays showed within- and between-run variabilities below 10%. At −20°C, only cathepsin D was stable up to 40 weeks. At −80°C, the cathepsin D, cathepsin E, and β-mannosidase activities did not change significantly up to 40 weeks, while β-glucocerebrosidase activity was stable up to 32 weeks. The β-galactosidase and α-fucosidase activities significantly increased (+54.9±38.08% after 4 weeks and +88.94±36.19% after 16 weeks, respectively). Up to four freeze/thaw cycles did not significantly affect the activities of cathepsins D and E. The β-glucocerebrosidase activity showed a slight decrease (−14.6%) after two freeze/thaw cycles. The measurement of lysosomal enzyme activities in cerebrospinal fluid is reliable and reproducible if pre-analytical factors are accurately taken into consideration. Therefore, the analytical recommendations that ensue from this study may contribute to the establishment of actual values for the activities of cerebrospinal fluid lysosomal enzymes as putative biomarkers for Parkinson's disease and other neurodegenerative disorders. PMID:24983953

  14. Brain-derived neurotrophic factor mediates the activity-dependent regulation of inhibition in neocortical cultures.

    PubMed

    Rutherford, L C; DeWan, A; Lauer, H M; Turrigiano, G G

    1997-06-15

    The excitability of cortical circuits is modulated by interneurons that release the inhibitory neurotransmitter GABA. In primate and rodent visual cortex, activity deprivation leads to a decrease in the expression of GABA. This suggests that activity is able to adjust the strength of cortical inhibition, but this has not been demonstrated directly. In addition, the nature of the signal linking activity to GABA expression has not been determined. Activity is known to regulate the expression of the neurotrophin brain-derived neurotrophic factor (BDNF), and BDNF has been shown to influence the phenotype of GABAergic interneurons. We use a culture system from postnatal rat visual cortex to test the hypothesis that activity is regulating the strength of cortical inhibition through the regulation of BDNF. Cultures were double-labeled against GABA and the neuronal marker MAP2, and the percentage of neurons that were GABA-positive was determined. Blocking spontaneous activity in these cultures reversibly decreased the number of GABA-positive neurons without affecting neuronal survival. Voltage-clamp analysis of inhibitory currents demonstrated that activity blockade also decreased GABA-mediated inhibition onto pyramidal neurons and raised pyramidal neuron firing rates. All of these effects were prevented by incubation with BDNF during activity blockade, but not by neurotrophin 3 or nerve growth factor. Additionally, blockade of neurotrophin signaling mimicked the effects of activity blockade on GABA expression. These data suggest that activity regulates cortical inhibition through a BDNF-dependent mechanism and that this neurotrophin plays an important role in the control of cortical excitability.

  15. Natural Product-Derived Small Molecule Activators of Hypoxia-Inducible Factor-1 (HIF-1)

    PubMed Central

    Nagle, Dale G.; Zhou, Yu-Dong

    2010-01-01

    Hypoxia-inducible factor-1 (HIF-1) is a key mediator of oxygen homeostasis that was first identified as a transcription factor that is induced and activated by decreased oxygen tension. Upon activation, HIF-1 upregulates the transcription of genes that promote adaptation and survival under hypoxic conditions. HIF-1 is a heterodimer composed of an oxygen-regulated subunit known as HIF-1α and a constitutively expressed HIF-1β subunit. In general, the availability and activity of the HIF-1α subunit determines the activity of HIF-1. Subsequent studies have revealed that HIF-1 is also activated by environmental and physiological stimuli that range from iron chelators to hormones. Preclinical studies suggest that HIF-1 activation may be a valuable therapeutic approach to treat tissue ischemia and other ischemia/hypoxia-related disorders. The focus of this review is natural product-derived small molecule HIF-1 activators. Natural products, relatively low molecular weight organic compounds produced by plants, animals, and microbes, have been and continue to be a major source of new drugs and molecular probes. The majority of known natural product-derived HIF-1 activators were discovered through pharmacological evaluation of specifically selected individual compounds. The combination of natural products chemistry with appropriate high-throughput screening bioassays could provide an alternative approach to discover novel natural product-derived HIF-1 activators. Potent natural product-derived HIF-1 activators that exhibit a low level of toxicity and side effects hold promise as new treatment options for diseases such as myocardial and peripheral ischemia, and as chemopreventative agents that could be used to reduce the level of ischemia/reperfusion injury following heart attack and stroke. PMID:16842166

  16. Drosophila pico and its mammalian ortholog lamellipodin activate serum response factor and promote cell proliferation.

    PubMed

    Lyulcheva, Ekaterina; Taylor, Eleanor; Michael, Magdalene; Vehlow, Anne; Tan, Shengjiang; Fletcher, Adam; Krause, Matthias; Bennett, Daimark

    2008-11-01

    MIG-10/RIAM/lamellipodin (MRL) proteins link activated Ras-GTPases with actin regulatory Ena/VASP proteins to induce local changes in cytoskeletal dynamics and cell motility. MRL proteins alter monomeric (G):filamentous (F) actin ratios, but the impact of these changes had not been fully appreciated. We report here that the Drosophila MRL ortholog, pico, is required for tissue and organismal growth. Reduction in pico levels resulted in reduced cell division rates, growth retardation, increased G:F actin ratios and lethality. Conversely, pico overexpression reduced G:F actin ratios and promoted tissue overgrowth in an epidermal growth factor (EGF) receptor (EGFR)-dependent manner. Consistently, in HeLa cells, lamellipodin was required for EGF-induced proliferation. We show that pico and lamellipodin share the ability to activate serum response factor (SRF), a transcription factor that responds to reduced G:F-actin ratios via its co-factor Mal. Genetics data indicate that mal/SRF levels are important for pico-mediated tissue growth. We propose that MRL proteins link EGFR activation to mitogenic SRF signaling via changes in actin dynamics.

  17. Neuroprotective effects of physical activity on the brain: a closer look at trophic factor signaling.

    PubMed

    Phillips, Cristy; Baktir, Mehmet Akif; Srivatsan, Malathi; Salehi, Ahmad

    2014-01-01

    While the relationship between increased physical activity and cognitive ability has been conjectured for centuries, only recently have the mechanisms underlying this relationship began to emerge. Convergent evidence suggests that physical activity offers an affordable and effective method to improve cognitive function in all ages, particularly the elderly who are most vulnerable to neurodegenerative disorders. In addition to improving cardiac and immune function, physical activity alters trophic factor signaling and, in turn, neuronal function and structure in areas critical for cognition. Sustained exercise plays a role in modulating anti-inflammatory effects and may play a role in preserving cognitive function in aging and neuropathological conditions. Moreover, recent evidence suggests that myokines released by exercising muscles affect the expression of brain-derived neurotrophic factor synthesis in the dentate gyrus of the hippocampus, a finding that could lead to the identification of new and therapeutically important mediating factors. Given the growing number of individuals with cognitive impairments worldwide, a better understanding of how these factors contribute to cognition is imperative, and constitutes an important first step toward developing non-pharmacological therapeutic strategies to improve cognition in vulnerable populations.

  18. Cbl competitively inhibits epidermal growth factor-induced activation of phospholipase C-gamma1.

    PubMed

    Choi, Jang Hyun; Bae, Sun Sik; Park, Jong Bae; Ha, Sang Hoon; Song, Hebok; Kim, Jae-Ho; Cocco, Lucio; Ryu, Sung Ho; Suh, Pann-Ghill

    2003-04-30

    Phospholipase C-gamma1 (PLC-gamma1) plays pivotal roles in cellular growth and proliferation through its two Src homology (SH) 2 domains and its single SH3 domain, which interact with signaling molecules in response to various growth factors and hormones. However, the role of the SH domains in the growth factor-induced regulation of PLC-gamma1 is unclear. By peptide-mass fingerprinting analysis we have identified Cbl as a binding protein for the SH3 domain of PLC-gamma1 from rat pheochromatocyte PC12 cells. Association of Cbl with PLC-gamma1 was induced by epidermal growth factor (EGF) but not by nerve growth factor (NGF). Upon EGF stimulation, both Cbl and PLC-gamma1 were recruited to the activated EGF receptor through their SH2 domains. Mutation of the SH2 domains of either Cbl or PLC-gamma1 abrogated the EGF-induced interaction of PLC-gamma1 with Cbl, indicating that SH2-mediated translocation is essential for the association of PLC-gamma1 and Cbl. Overexpression of Cbl attenuated EGF-induced tyrosine phosphorylation and the subsequent activation of PLC-gamma1 by interfering competitively with the interaction between PLC-gamma1 and EGFR. Taken together, these results provide the first indications that Cbl may be a negative regulator of intracellular signaling following EGF-induced PLC-gamma1 activation.

  19. Interactions of Aspergillus fumigatus with endothelial cells: internalization, injury, and stimulation of tissue factor activity.

    PubMed

    Lopes Bezerra, Leila M; Filler, Scott G

    2004-03-15

    Invasive aspergillosis causes significant mortality among patients with hematologic malignancies. This infection is characterized by vascular invasion and thrombosis. To study the pathogenesis of invasive aspergillosis, we investigated the interactions of Aspergillus fumigatus conidia and hyphae with endothelial cells in vitro. We found that both forms of the organism induced endothelial cell microfilament rearrangement and subsequent endocytosis. Conidia were endocytosed 2-fold more avidly than hyphae, and endocytosis was independent of fungal viability. Endocytosed conidia and hyphae caused progressive endothelial cell injury after 4 hours of infection. Live conidia induced more endothelial cell injury than did live hyphae. However, endothelial cell injury caused by conidia was dependent on fungal viability, whereas injury caused by hyphae was not, indicating that conidia and hyphae injure endothelial cells by different mechanisms. Neither live nor killed conidia increased tissue factor activity of endothelial cells. In contrast, both live and killed hyphae stimulated significant endothelial cell tissue factor activity, as well as the expression of tissue factor antigen on the endothelial cell surface. These results suggest that angioinvasion and thrombosis caused by A fumigatus hyphae in vivo may be due in part to endothelial cell invasion, induction of injury, and stimulation of tissue factor activity.

  20. A serum factor that activates the phosphatidylinositol phosphate signaling system in Xenopus oocytes.

    PubMed Central

    Tigyi, G; Dyer, D; Matute, C; Miledi, R

    1990-01-01

    Blood sera from many vertebrate species elicit large oscillatory chloride currents in oocytes from the frog Xenopus laevis. Rabbit serum was active at dilutions as great as one part in 10 million. Intracellularly applied serum was ineffective, and externally applied serum failed to trigger oscillatory currents when the intracellular level of ionized calcium was prevented from rising by loading the oocyte with EGTA. The serum also caused an increase of inositol 1,4,5-trisphosphate in the oocyte. We conclude that serum contains a factor which activates a membrane receptor that is coupled to the phosphatidylinositol second messenger system. The active factor is a protein with an apparent molecular mass of 60-70 kDa in gel permeation chromatography. Although the normal function of the serum factor is still unknown, it may have far-reaching implications, because it acts on the multifunctional phosphatidylinositol phosphate signaling system. Also, because of its great potency the serum factor and Xenopus oocytes are very useful for probing the operation of the phosphatidylinositol system. PMID:1689488

  1. [Physical activity during commuting by adults and elderly in Brazil: prevalence and associated factors].

    PubMed

    Madeira, Marina Cordeiro; Siqueira, Fernando Carlos Vinholes; Facchini, Luiz Augusto; Silveira, Denise Silva da; Tomasi, Elaine; Thumé, Elaine; Silva, Suele Manjourany; Dilélio, Alitéia; Piccini, Roberto Xavier

    2013-01-01

    Evidence in the literature shows that physical activity associated with commuting (routine coming and going) can have a positive impact on health. The current study describes physical activity during commuting and some associated factors. A cross-sectional population-based study was conducted with 12,402 adults and 6,624 elderly in 100 municipalities (counties) from 23 States of Brazil. The outcome was based on the commuting section from the long version of the International Physical Activity Questionnaire (IPAQ). Prevalence of insufficient physical activity during commuting (< 150 minutes per week) was 66.6% in adults and 73.9% in the elderly. Among the elderly, the very old showed 25 times higher odds of being insufficiently active as compared to younger elders. Individuals with self-reported "white" skin color were less active in commuting. The findings show that prevalence of physical activity in commuting in Brazil is low, and that encouraging physically active commuting can be an effective strategy for increasing levels of physical activity and improving health.

  2. Triggering neurotrophic factor actions through adenosine A2A receptor activation: implications for neuroprotection

    PubMed Central

    Sebastião, Ana M; Ribeiro, Joaquim A

    2009-01-01

    G protein coupled receptors and tropomyosin-related kinase (Trk) receptors have distinct structure and transducing mechanisms; therefore, cross-talk among them was unexpected. Evidence has, however, accumulated showing that tonic adenosine A2A receptor activity is a required step to allow synaptic actions of neurotrophic factors, namely upon synaptic transmission at both pre- and post-synaptic level as well as upon synaptic plasticity. An enhancement of A2A receptor tonus upon ageing may partially compensate the loss of TrkB receptors, rescuing to certain degree the facilitatory action of brain derived neurotrophic factor in aged animals, which might prove particularly relevant in the prevention of neurodegeneration upon ageing. A2A receptors also trigger synaptic actions of other neurotrophic factors, such as glial derived neurotrophic factor at dopaminergic striatal nerve endings. The growing evidence that tonic adenosine A2A receptor activity is a crucial step to allow actions of neurotrophic factors in neurones will be reviewed and discussed in the light of therapeutic strategies for neurodegenerative diseases. PMID:19508402

  3. Novel risk factors of cardiovascular disease and their associations between obesity, physical activity and physical fitness.

    PubMed

    Buchan, Duncan S; Thomas, Non E; Baker, Julien S

    2012-02-17

    The prevalence of cardiovascular disease (CVD) is increasing around the globe and is the leading cause of death around the world. Though once thought of as an adult problem, it is now recognised that the early manifestations of disease may occur during childhood. Numerous risk factors have been linked to CVD with much of the research focusing on understanding the prevalence and relationship of traditional risk factors such as dyslipidemia, smoking, diabetes mellitus, hypertension, obesity, psychosocial stress, poor diet, physical inactivity and alcohol consumption to the early etiology of disease. While this line of investigation has greatly enhanced our understanding of the relationship between these risk factors and disease, they do not fully explain all cardiovascular events. To enhance our understanding and help with the management of CVD, investigations that involve the measurement of traditional as well as novel risk factors may be necessary. Public health strategies that aim to reduce the prevalence of obesity and overweight encourage youth to increase their physical activity levels as a means of protecting against poor cardiometabolic profiles. Interventions that increase physical activity levels and improve cardiorespiratory fitness cause a reduction in certain CVD risk factors but the lack of agreement between findings makes it impossible to give precise recommendations that will ensure CVD risk reduction. Yet it is important that research continues in order to establish the most appropriate means of improving the health and well-being of those at most risk of future CVD.

  4. RhoA GTPase oxidation stimulates cell proliferation via nuclear factor-κB activation.

    PubMed

    Kim, Jae-Gyu; Kwon, Hyung-Joo; Wu, Guang; Park, Yohan; Lee, Jae-Yong; Kim, Jaebong; Kim, Sung-Chan; Choe, Myoen; Kang, Seung Goo; Seo, Goo-Young; Kim, Pyeung-Hyeun; Park, Jae-Bong

    2017-02-01

    Reactive oxygen species (ROS) produced by many kinds of stimuli are essential for cellular signaling including cell proliferation. The dysregulation of ROS, therefore, is related to a variety of diseases including cancer. However, it was not clearly elucidated how ROS regulate cell proliferation and tumorigenesis. In this study, we investigated a mechanism by which the oxidation of RhoA GTPase regulates nuclear factor-κB (NF-κB) and cell proliferation. Hydrogen peroxide activated NF-κB and RhoA GTPase, but did not activate RhoA C16/20A mutant, an oxidation-resistant form. Remarkably, the oxidation of RhoA reduced its affinity towards RhoGDI, leading to the dissociation of RhoA-RhoGDI complex. Si-Vav2, a guanine nucleotide exchange factor (GEF), inhibited RhoA activation upon hydrogen peroxide. The oxidized RhoA (oxRhoA)-GTP was readily bound to IκB kinase γ (IKKγ), whereas oxidized RhoGDI did not bind to IKKγ. The oxRhoA-GTP bound to IKKγ activated IKKβ, leading to IκB phosphorylation and degradation, consequently NF-κB activation. Hydrogen peroxide induced cell proliferation, but RhoA C16/20A mutant suppressed cell proliferation and tumorigenesis. Conclusively, RhoA oxidation at Cys16/20 is critically involved in cell proliferation and tumorigenesis through NF-κB activation in response to ROS.

  5. Platelet-Activating Factor Induces Epigenetic Modifications in Human Mast Cells.