Sample records for eif5a1 involves activation

  1. Esophageal cancer alters the expression of nuclear pore complex binding protein Hsc70 and eIF5A-1.

    PubMed

    Moghanibashi, Mehdi; Rastgar Jazii, Ferdous; Soheili, Zahra-Soheila; Zare, Maryam; Karkhane, Aliasghar; Parivar, Kazem; Mohamadynejad, Parisa

    2013-06-01

    Nuclear pore complex (NPC) is the only corridor for macromolecules exchange between nucleus and cytoplasm. NPC and its components, nucleoporins, play important role in the diverse physiological processes including macromolecule exchange, chromosome segregation, apoptosis and gene expression. Recent reports also suggest involvement of nucleoporins in carcinogenesis. Applying proteomics, we analyzed expression pattern of the NPC components in a newly established esophageal cancer cell line from Persia (Iran), the high-risk region for esophageal cancer. Our results indicate overexpression of Hsc70 and downregulation of subunit alpha type-3 of proteasome, calpain small subunit 1, and eIF5A-1. Among these proteins, Hsc70 and eIF5A-1 are in direct interaction with NPC and involved in the nucleocytoplasmic exchange. Hsc70 plays a critical role as a chaperone in the formation of a cargo-receptor complex in nucleocytoplasmic transport. On the other hand, it is an NPC-associated protein that binds to nucleoporins and contributes in recycling of the nucleocytoplasmic transport receptors in mammals and affects transport of proteins between nucleus and cytoplasm. The other nuclear pore interacting protein: eIF5A-1 binds to the several nucleoporins and participates in nucleocytoplasmic transport. Altered expression of Hsc70 and eIF5A-1 may cause defects in nucleocytoplasmic transport and play a role in esophageal carcinogenesis. PMID:23539416

  2. Essential role of eIF5A-1 and deoxyhypusine synthase in mouse embryonic development.

    PubMed

    Nishimura, Kazuhiro; Lee, Seung Bum; Park, Jong Hwan; Park, Myung Hee

    2012-02-01

    The eukaryotic initiation factor 5A (eIF5A) contains a polyamine-derived amino acid, hypusine [N(?)-(4-amino-2-hydroxybutyl)lysine]. Hypusine is formed post-translationally by the addition of the 4-aminobutyl moiety from the polyamine spermidine to a specific lysine residue, catalyzed by deoxyhypusine synthase (DHPS), and subsequent hydroxylation by deoxyhypusine hydroxylase (DOHH). The eIF5A precursor protein and both of its modifying enzymes are highly conserved, suggesting a vital cellular function for eIF5A and its hypusine modification. To address the functions of eIF5A and the first modification enzyme, DHPS, in mammalian development, we knocked out the Eif5a or the Dhps gene in mice. Eif5a heterozygous knockout mice and Dhps heterozygous knockout mice were viable and fertile. However, homozygous Eif5a1 (gt/gt) embryos and Dhps (gt/gt) embryos died early in embryonic development, between E3.5 and E7.5. Upon transfer to in vitro culture, homozygous Eif5a (gt/gt) or Dhps (gt/gt) blastocysts at E3.5 showed growth defects when compared to heterozygous or wild type blastocysts. Thus, the knockout of either the eIF5A-1 gene (Eif5a) or of the deoxyhypusine synthase gene (Dhps) caused early embryonic lethality in mice, indicating the essential nature of both eIF5A-1 and deoxyhypusine synthase in mammalian development. PMID:21850436

  3. Promoting Active Involvement in Classrooms

    ERIC Educational Resources Information Center

    Conderman, Greg; Bresnahan, Val; Hedin, Laura

    2012-01-01

    This article presents a rationale for using active involvement techniques, describes large- and small-group methods based on their documented effectiveness and applicability to K-12 classrooms, and illustrates their use. These approaches include ways of engaging students in large groups (e.g., unison responses, response cards, dry-erase boards,…

  4. Promoting Active Involvement in Today's Classrooms

    ERIC Educational Resources Information Center

    Conderman, Greg; Bresnahan, Val; Hedin, Laura

    2011-01-01

    In today's diverse classrooms and age of accountability, teachers need to use efficient, research-based instructional approaches that engage all students, promote interest and variety in learning and teaching, and provide immediate and continuous informal assessment data. This article presents a rationale for using active involvement techniques,…

  5. Motivating Teacher Involvement in Professional Growth Activities.

    ERIC Educational Resources Information Center

    Wright, Ruth

    1985-01-01

    The evidence from research using expectancy theory is synthesized to develop a contingency model of incentives for involving teachers in professional development. Research findings that focused on the administrative challenge of motivating teachers to engage in curriculum development tasks are used to test the model. (MLF)

  6. DESIGN CONSIDERATION INVOLVING ACTIVE SEDIMENT CAPS (PRESENTATION)

    EPA Science Inventory

    When contaminated sediments pose unacceptable risks to human health and the environment, management activities such as removal, treatment, or isolation of contaminated sediments may be required. Various capping designs are being considered for isolating contaminated sediment are...

  7. DESIGN CONSIDERATION INVOLVING ACTIVE SEDIMENT CAPS

    EPA Science Inventory

    When contaminated sediments pose unacceptable risks to human health and the environment, management activities such as removal, treatment, or isolation of contaminated sediments may be required. Various capping designs are being considered for isolating contaminated sediment are...

  8. The Director of Physical Activity and Staff Involvement

    ERIC Educational Resources Information Center

    Heidorn, Brent; Centeio, Erin

    2012-01-01

    Faculty and staff involvement in the Comprehensive School Physical Activity Program (CSPAP) begins with the Director of Physical Activity (DPA) motivating them to "buy in" to the need for a CSPAP. The DPA will need to train staff to develop and integrate physical activity throughout the school day, encourage them to be involved in the before- and…

  9. Involvement of Parents in School Related Activities

    Microsoft Academic Search

    Rajni Dhingra; Sarika Manhas; Neetu Sethi

    2007-01-01

    The present paper examined the participation of parents in school related activities. It further aimed to list various means of communication used by parents to get information about their child's school performance and to suggest intervention strategies for improvement of parent school relationship. The sample for the study comprised of 1000 parents of school going children (Classes I-V) selected by

  10. Victimisation Among Those Involved In Underage Commercial Sexual Activity

    Microsoft Academic Search

    Miriam Saphira; Averil Herbert; Ngati Maniapoto

    This study explores the incidence of violence and childhood sexual abuse among people who became involved in underage commercial sexual activity. Respondents who became prostitutes before the age of 18 years were asked about childhood sexual abuse and about sexual and physical assault since beginning commercial sexual activity. Rates of childhood sexual abuse were higher than those of a South

  11. Empirical Evidence or Intuition? An Activity Involving the Scientific Method

    ERIC Educational Resources Information Center

    Overway, Ken

    2007-01-01

    Students need to have basic understanding of scientific method during their introductory science classes and for this purpose an activity was devised which involved a game based on famous Monty Hall game problem. This particular activity allowed students to banish or confirm their intuition based on empirical evidence.

  12. Letter to the Editors Schizophrenia involves impairment in the activation

    E-print Network

    Park, Sohee

    Letter to the Editors Schizophrenia involves impairment in the activation of intentions by counterfactual thinking Schizophrenia has been associated with impairment of counterfactual thinking (Hooker et al., 2000), defined as cognitions about alternatives to past out- comes (i.e., what might have been

  13. Identifying Associations between Student Achievement and Parental Involvement Activities

    ERIC Educational Resources Information Center

    Waddle, Ann R.

    2011-01-01

    The revision and renewal of the Elementary and Secondary Education Act of 1965 will likely expand its parental involvement component to engage educators, parents, and community partners in supporting public education for children. This revisions call for best practices, but current literature fails to identify specific activities associated…

  14. Adolescent Involvement in Extracurricular Activities: Influences on Leadership Skills

    ERIC Educational Resources Information Center

    Hancock, Donna; Dyk, Patricia Hyjer; Jones, Kenneth

    2012-01-01

    Study examined adolescents' participation in sports, school, and community extracurricular activities to assess the influence of different involvement roles and adult support on leadership skills. The study found that males and females who perceived their adult support more positively had more positive perceptions of their leadership skills.…

  15. Patterns of Arm Muscle Activation Involved in Octopus Reaching Movements

    E-print Network

    Hochner, Binyamin

    Patterns of Arm Muscle Activation Involved in Octopus Reaching Movements Yoram Gutfreund,1 Tamar, Stazione Zoologica "A. Dohrn," Naples 80121, Italy The extreme flexibility of the octopus arm allows it to perform many different movements, yet octopuses reach toward a tar- get in a stereotyped manner using

  16. 16 CFR 1031.5 - Criteria for Commission involvement in voluntary standards activities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...for Commission involvement in voluntary standards activities. 1031.5 Section 1031...COMMISSION EMPLOYEE INVOLVEMENT IN VOLUNTARY STANDARDS ACTIVITIES General Policies § 1031...for Commission involvement in voluntary standards activities. The Commission...

  17. 16 CFR 1031.5 - Criteria for Commission involvement in voluntary standards activities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...for Commission involvement in voluntary standards activities. 1031.5 Section 1031...COMMISSION EMPLOYEE INVOLVEMENT IN VOLUNTARY STANDARDS ACTIVITIES General Policies § 1031...for Commission involvement in voluntary standards activities. The Commission...

  18. Involvement in 12-step activities and treatment outcomes.

    PubMed

    Zemore, Sarah E; Subbaraman, Meenakshi; Tonigan, J Scott

    2013-01-01

    This study addresses the relative importance of specific 12-step activities to recovery, and how treatment affects participation in those activities. Data were from a clinical trial testing a 12-step facilitation intervention called MAAEZ (Making AA [Alcohol Anonymous] Easier). Participants (N = 508) were recruited at treatment entry. Analyses examined 8 activities measured at baseline, 7 weeks, 6 months, and 12 months. In simultaneous equations, meeting attendance and having a sponsor were the only strong and consistent predictors of abstinence across time points, though other activities (i.e., use of a home group, befriending members, service work, and reading the literature) were significant in some analyses. Treatment involvement had mixed effects on activity participation over time. Contradicting research suggesting that meeting attendance contributes little beyond other 12-step activities, the current results highlight the importance of consistent meeting attendance and sponsorship in recovery. The results suggest a need for enhanced facilitation of key activities even in typical 12-step-oriented treatment. PMID:23327505

  19. A novel receptor involved in T-cell activation

    Microsoft Academic Search

    Benjamin G. Cocks; Chia-Chun J. Chang; Hans Yssel; Jan E. de Vries; Gregorio Aversa

    1995-01-01

    OPTIMAL T-cell activation and T-cell expansion require triggering by T-cell antigen receptors and co-stimulatory signals provided by accessory cells1á¤-3. A major co-stimulatory pathway involves crosslinking the CD28 molecule on T cells by its ligands CD80 or CD86 expressed on antigen-presenting cells4á¤-7. But recent studies8,9 on CD28-deficient mice have indicated that CD28 is not required for all T-cell responses and that

  20. Involvement of trigeminal astrocyte activation in masseter hyperalgesia under stress.

    PubMed

    Zhao, Ya-Juan; Liu, Yang; Li, Qiang; Zhao, Yin-Hua; Wang, Jian; Zhang, Min; Chen, Yong-Jin

    2015-04-01

    It is commonly accepted that psychological stress contributes to the development of temporomandibular joint disorders, in which chronic orofacial pain is the main symptom. However, the central mechanism underlying the development of these disorders has remained unclear. The current study was performed to determine the involvement of the glia in the trigeminal spinal subnucleus caudalis in stress-induced increases in masseter muscle hyperalgesia in rats. After being subjected to chronic restraint stress, the animals showed decreased body weight gain, behavioral changes and marked masseter allodynia. We also found that astrocytes, but not microglia, in the trigeminal subnucleus caudalis (Vc) were dramatically activated. A further analysis was undertaken to investigate the contribution of the glia; we intrathecally injected l-?-aminoadipate (astrocyte-specific inhibitor) and/or minocycline (microglia-specific inhibitor) into the stressed rats. Our results showed that l-?-aminoadipate (LAA), but not minocycline, could significantly attenuate the mechanical masseter allodynia and behavioral changes induced by restraint stress. In addition, the expression of interleukin-1? (IL-1?) and phosphorylated N-methyl-d-aspartic acid receptor 1 (p-NR1) in the Vc was significantly increased after chronic restraint stress, whereas LAA dramatically inhibited the overexpression of IL-1? and p-NR1. Taken together, these results suggest that activated astrocytes in the Vc may be one of the most important factors in the pathophysiology of masseter hyperalgesia induced by restraint stress and the following overexpression of IL-1? and excessive NMDAR phosphorylation may ultimately contribute to masseter hyperalgesia. Thus, inhibiting spinal astrocytic activation may represent a novel therapeutic strategy for the treatment of orofacial pain induced by stress. PMID:25660342

  1. Head Start Parent Involvement Activities: Measuring the Effect of School Based Parent Involvement Activities on Parent Efficacy in Early Childhood Learning

    ERIC Educational Resources Information Center

    Quadri, Khadijat O.

    2012-01-01

    Purpose: The purpose of this position paper was to examine the impact of school based parent involvement activities on parent efficacy. Methodology: The paper explores research studies into school based activities on long term parent efficacy. Conclusions: Most schools are involving parents in school-based activities in a variety of ways but the…

  2. Time window for cognitive activity involved in emotional processing

    PubMed Central

    2014-01-01

    Background From previous studies it is becoming evident that the processing of unpleasant stimuli occurs early (0 to 300 ms); however, it is not clear how cognitive processing related to pleasant/unpleasant emotions occurs at later time windows (?300 ms). On the other hand, as evident from the previous reports, BIS and BAS personality traits are strongly associated with unpleasant and pleasant responses, respectively. Therefore, in the present study, we aim to identify the time window involved in human pleasant/unpleasant emotional processing by investigating ERP components correlated with BIS/BAS personality traits. Methods Twenty-nine men took part in the study and recording ERP during presented sounds. BIS/BAS score was calculated using the Japanese edition of the BIS/BAS questionnaire. Results Significant correlation was not observed between BIS and BAS scores. A significant and positive correlation was observed between N100 amplitude and BIS score. A positive correlation was found between BAS fun seeking subscale score and LPP amplitude. Our findings did not contradict previous study results. Conclusions Our results suggest that the processing of unpleasant emotions takes place early on, since N100 response was larger in high BIS subjects who are known to be sensitive to unpleasant emotions. LPP was larger in high BAS subjects who are known to be sensitive to pleasant emotions. The LPP was considered to be augmented because the ACC activity level during pleasant emotions reflected on LPP. PMID:25056735

  3. 15 CFR 712.2 - Restrictions on activities involving Schedule 1 chemicals.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...on activities involving Schedule 1 chemicals. 712.2 Section 712.2 Commerce...SECURITY, DEPARTMENT OF COMMERCE CHEMICAL WEAPONS CONVENTION REGULATIONS ACTIVITIES INVOLVING SCHEDULE 1 CHEMICALS § 712.2 Restrictions on...

  4. 15 CFR 712.2 - Restrictions on activities involving Schedule 1 chemicals.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...on activities involving Schedule 1 chemicals. 712.2 Section 712.2 Commerce...SECURITY, DEPARTMENT OF COMMERCE CHEMICAL WEAPONS CONVENTION REGULATIONS ACTIVITIES INVOLVING SCHEDULE 1 CHEMICALS § 712.2 Restrictions on...

  5. Organized Activity Involvement among Rural Youth: Gender Differences in Associations between Activity Type and Developmental Outcomes

    ERIC Educational Resources Information Center

    Ferris, Kaitlyn A.; Oosterhoff, Benjamin; Metzger, Aaron

    2013-01-01

    The current study examined associations between organized activity involvement, academic achievement, and problem behavior in a sample of youth from a non-agricultural based rural community (M[subscript age] = 15.26, Age range = 11-19 years, N = 456). Analyses examined whether associations varied as a function of adolescent gender and age.…

  6. Antithrombin Regulates Matriptase Activity Involved in Plasmin Generation, Syndecan Shedding, and HGF Activation in Keratinocytes

    PubMed Central

    Chen, Ya-Wen; Xu, Zhenghong; Baksh, Adrienne N. H.; Wang, Jehng-Kang; Chen, Chiu-Yuan; Swanson, Richard; Olson, Steve T.; Kataoka, Hiroaki; Johnson, Michael D.; Lin, Chen-Yong

    2013-01-01

    Matriptase, a membrane-associated serine protease, plays an essential role in epidermal barrier function through activation of the glycosylphosphatidylinositol (GPI)-anchored serine protease prostasin. The matriptase-prostasin proteolytic cascade is tightly regulated by hepatocyte growth factor activator inhibitor (HAI)-1 such that matriptase autoactivation and prostasin activation occur simultaneously and are followed immediately by the inhibition of both enzymes by HAI-1. However, the mechanisms whereby matriptase acts on extracellular substrates remain elusive. Here we report that some active matriptase can escape HAI-1 inhibition by being rapidly shed from the cell surface. In the pericellular environment, shed active matriptase is able to activate hepatocyte growth factor (HGF), accelerate plasminogen activation, and shed syndecan 1. The amount of active matriptase shed is inversely correlated with the amount of antithrombin (AT) bound to the surface of the keratinocytes. Binding of AT to the surface of keratinocytes is dependent on a functional heparin binding site, Lys-125, and that the N-glycosylation site Asn-135 be unglycosylated. This suggests that ?-AT, and not ?-AT, is responsible for regulation of pericellular matriptase activity in keratinocytes. Keratinocytes appear to rely on AT to regulate the level of pericellular active matriptase much more than breast and prostate epithelial cells in which AT regulation of matriptase activity occurs at much lower levels than keratinocytes. These results suggest that keratinocytes employ two distinct serine protease inhibitors to control the activation and processing of two different sets of matriptase substrates leading to different biological events: 1) HAI-1 for prostasin activation/inhibition, and 2) AT for the pericellular proteolysis involved in HGF activation, accelerating plasminogen activation, and shedding of syndecans. PMID:23675430

  7. Comparison of involvement between traditional and technology-assisted (Wii) physical activities in early childhood education

    Microsoft Academic Search

    Gretchen H Geng; Leigh P Disney

    2010-01-01

    This study compared the differences of involvement scale between traditional and technology assisted physical activities. Seventeen (12 girls and 5 boys) 5-year-olds participated in both traditional running game (15 minutes) and Wii Fit jogging game (15 minutes). Observation was used to study the child's level of involvement. The study found that technology assisted physical activities involved participants higher than traditional

  8. The Effects of Adolescent Activities on Delinquency: A Differential Involvement Approach

    Microsoft Academic Search

    Siu Kwong Wong

    2005-01-01

    T. Hirschi’s (1969, Causes of Delinquency. University of California Press, Berkeley, CA) control theory proposes that involvement, as an element of the social bond, should reduce delinquency. But, research studies have found that the effect of involvement is rather weak. This study reformulates Hirschi’s involvement hypothesis by posing involvement as a social setting variable and a differential factor. Certain activities

  9. Extracurricular Activity Involvement and Adolescent Self-Esteem

    ERIC Educational Resources Information Center

    Kort-Butler, Lisa A.

    2012-01-01

    Structured extracurricular activity participation has been linked to self-esteem and other indicators of positive youth development. This article describes the theoretical basis for this relationship, centering on extracurricular activities as a location for identity development. A summary of the empirical evidence points to the importance of…

  10. Human tracking studies involving an actively powered, augmented exoskeleton

    Microsoft Academic Search

    D. W. Repperger; B. O. Hill; C. Hasser; M. Roark; C. A. Phillips

    1996-01-01

    An actively powered, augmented, exoskeleton system is studied within a speed-accuracy performance task framework with human subjects. This system has a dual use in military applications as well as for the rehabilitation of patients with neuromotor disorders

  11. Organized activity involvement, depressive symptoms, and social adjustment in adolescents: ethnicity and socioeconomic status as moderators.

    PubMed

    Randall, Edin T; Bohnert, Amy M

    2009-10-01

    The current cross-sectional study investigated the links between various dimensions of organized activity involvement and depressive symptoms, loneliness, and peer victimization in an ethnically and economically diverse sample of adolescents (N = 152; 58% female). Results indicate that adolescents who were involved in organized activities for more years also reported lower levels of loneliness. There was evidence of diminishing returns when adolescents were very highly involved in organized activities; those who were either under- or over-involved reported the highest levels of depressive symptoms. Conversely, findings indicate that adolescents who participated in a narrow or wide range of activity contexts reported the lowest levels of depressive symptoms. In addition, results suggested that the relation between organized activity involvement and adjustment differs among adolescents from diverse ethnic and socioeconomic backgrounds. Findings from the current study also underscore the importance of considering multiple indices of activity involvement when assessing its association with adjustment. PMID:19669899

  12. Artificial masculinization in tilapia involves androgen receptor activation.

    PubMed

    Golan, Matan; Levavi-Sivan, Berta

    2014-10-01

    Estrogens have a pivotal role in natural female sexual differentiation of tilapia while lack of steroids results in testicular development. Despite the fact that androgens do not participate in natural sex differentiation, synthetic androgens, mainly 17-?-methyltestosterone (MT) are effective in the production of all-male fish in aquaculture. The sex inversion potency of synthetic androgens may arise from their androgenic activity or else as inhibitors of aromatase activity. The current study is an attempt to differentiate between the two alleged activities in order to evaluate their contribution to the sex inversion process and aid the search for novel sex inversion agents. In the present study, MT inhibited aromatase activity, when applied in vitro as did the non-aromatizable androgen dihydrotestosterone (DHT). In comparison, exposure to fadrozole, a specific aromatase inhibitor, was considerably more effective. Androgenic activity of MT was evaluated by exposure of Sciaenochromis fryeri fry to the substance and testing for the appearance of blue color. Flutamide, an androgen antagonist, administered concomitantly with MT, reduced the appearance of the blue color and the sex inversion potency of MT in a dose-dependent manner. In tilapia, administration of MT, fadrozole or DHT resulted in efficient sex inversion while flutamide reduced the sex inversion potency of all three compounds. In the case of MT and DHT the decrease in sex inversion efficiency caused by flutamide is most likely due to the direct blocking of the androgen binding to its cognate receptor. The negative effect of flutamide on the efficiency of the fadrozole treatment may indicate that the masculinizing activity of fadrozole may be attributed to excess, un-aromatized, androgens accumulated in the differentiating gonad. The present study shows that when androgen receptors are blocked, there is a reduction in the efficiency of sex inversion treatments. Our results suggest that in contrast to natural sex differentiation, during sex inversion treatments, androgens, either endogenous or exogenous, participate in inducing testicular differentiation. PMID:24815887

  13. The Involvement of Children in Commercial Sexual Activity

    Microsoft Academic Search

    Miriam Saphira; Averil Herbert; Ngati Maniapoto

    This study explores the factors leading to the first i nvolvement of a young person in underage prostitution. The target group were sex workers who began commercial sexual activities before the age of 18. Questions focussed on the first time payment was received for sex. The respondents outlined the factors leading to this first i nvolvement. In a majority of

  14. BIOLOGICAL ACTIVITY AND POTENTIAL REMEDIATION INVOLVING GEOTEXTILE LANDFILL LEACHATE FILTERS

    EPA Science Inventory

    This paper presents the results of a biological growth study in geotextile filters used in landfill leachate collection systems. fter reviewing the first year's activity, a completely new experimental approach has been taken. sing 100 mm diameter columns for the experimental incu...

  15. Does the activity involves Research: a systematic investigation

    E-print Network

    Oliver, Douglas L.

    of these questions out of order can lead to incorrect conclusions. Review the next six flow diagrams to determine to a predefined plan for the data collection and analysis 3) the performance of data analysis to evaluate: Activity is not research. NO Determination of Human Subjects Research Chart Start here Does the research

  16. Mutator transposon activation after UV-B involves chromatin remodeling.

    PubMed

    Qüesta, Julia I; Walbot, Virginia; Casati, Paula

    2010-05-16

    Spontaneous silencing of MuDR/Mu transposons occurs in approximately 10-100% of the progeny of an active plant, and once silenced reactivation is very rare. To date, only radiation treatments have reactivated silenced Mu; for example UV-B radiation reactivated Mutator activities. Here we have investigated possible mechanisms by which UV-B could reactivate Mu transposons by monitoring transcript abundance, epigenetic DNA marks, and chromatin factors associated with these elements. We demonstrate that both mudrA and B transcripts are expressed at higher levels after an 8 h-UV-B treatment, in both active Mutator and silencing plants, and that different chromatin remodeling events occur in the promoter regions of MuDR than in non-autonomous Mu1 elements. Increased transcript abundance is accompanied by an increase in histone H3 acetylation and by decreased DNA and H3K9me2 methylation. No changes in siRNA levels were detected. In contrast, the decrease in H3K9me2 present at Mu elements after UV-B is significant in silencing plants, suggesting that early changes in H3 methylation in K9, chromatin remodeling, and transcription factor binding contribute directly to transposon reactivation by UV-B in maize. PMID:20421734

  17. Hemolysis-induced lethality involves inflammasome activation by heme

    PubMed Central

    Dutra, Fabianno F.; Alves, Letícia S.; Rodrigues, Danielle; Fernandez, Patricia L.; de Oliveira, Rosane B.; Golenbock, Douglas T.; Zamboni, Dario S.; Bozza, Marcelo T.

    2014-01-01

    The increase of extracellular heme is a hallmark of hemolysis or extensive cell damage. Heme has prooxidant, cytotoxic, and inflammatory effects, playing a central role in the pathogenesis of malaria, sepsis, and sickle cell disease. However, the mechanisms by which heme is sensed by innate immune cells contributing to these diseases are not fully characterized. We found that heme, but not porphyrins without iron, activated LPS-primed macrophages promoting the processing of IL-1? dependent on nucleotide-binding domain and leucine rich repeat containing family, pyrin domain containing 3 (NLRP3). The activation of NLRP3 by heme required spleen tyrosine kinase, NADPH oxidase-2, mitochondrial reactive oxygen species, and K+ efflux, whereas it was independent of heme internalization, lysosomal damage, ATP release, the purinergic receptor P2X7, and cell death. Importantly, our results indicated the participation of macrophages, NLRP3 inflammasome components, and IL-1R in the lethality caused by sterile hemolysis. Thus, understanding the molecular pathways affected by heme in innate immune cells might prove useful to identify new therapeutic targets for diseases that have heme release. PMID:25225402

  18. Hemolysis-induced lethality involves inflammasome activation by heme.

    PubMed

    Dutra, Fabianno F; Alves, Letícia S; Rodrigues, Danielle; Fernandez, Patricia L; de Oliveira, Rosane B; Golenbock, Douglas T; Zamboni, Dario S; Bozza, Marcelo T

    2014-09-30

    The increase of extracellular heme is a hallmark of hemolysis or extensive cell damage. Heme has prooxidant, cytotoxic, and inflammatory effects, playing a central role in the pathogenesis of malaria, sepsis, and sickle cell disease. However, the mechanisms by which heme is sensed by innate immune cells contributing to these diseases are not fully characterized. We found that heme, but not porphyrins without iron, activated LPS-primed macrophages promoting the processing of IL-1? dependent on nucleotide-binding domain and leucine rich repeat containing family, pyrin domain containing 3 (NLRP3). The activation of NLRP3 by heme required spleen tyrosine kinase, NADPH oxidase-2, mitochondrial reactive oxygen species, and K(+) efflux, whereas it was independent of heme internalization, lysosomal damage, ATP release, the purinergic receptor P2X7, and cell death. Importantly, our results indicated the participation of macrophages, NLRP3 inflammasome components, and IL-1R in the lethality caused by sterile hemolysis. Thus, understanding the molecular pathways affected by heme in innate immune cells might prove useful to identify new therapeutic targets for diseases that have heme release. PMID:25225402

  19. Laboratory activities involving transmissible spongiform encephalopathy causing agents

    PubMed Central

    Leunda, Amaya; Van Vaerenbergh, Bernadette; Baldo, Aline; Roels, Stefan; Herman, Philippe

    2013-01-01

    Since the appearance in 1986 of epidemic of bovine spongiform encephalopathy (BSE), a new form of neurological disease in cattle which also affected human beings, many diagnostic and research activities have been performed to develop detection and therapeutic tools. A lot of progress was made in better identifying, understanding and controlling the spread of the disease by appropriate monitoring and control programs in European countries. This paper reviews the recent knowledge on pathogenesis, transmission and persistence outside the host of prion, the causative agent of transmissible spongiform encephalopathies (TSE) in mammals with a particular focus on risk (re)assessment and management of biosafety measures to be implemented in diagnostic and research laboratories in Belgium. Also, in response to the need of an increasing number of European diagnostic laboratories stopping TSE diagnosis due to a decreasing number of TSE cases reported in the last years, decontamination procedures and a protocol for decommissioning TSE diagnostic laboratories is proposed. PMID:24055928

  20. Anticancer Activity of Metal Complexes: Involvement of Redox Processes

    PubMed Central

    Jungwirth, Ute; Kowol, Christian R.; Keppler, Bernhard K.; Hartinger, Christian G.; Berger, Walter; Heffeter, Petra

    2012-01-01

    Cells require tight regulation of the intracellular redox balance and consequently of reactive oxygen species for proper redox signaling and maintenance of metal (e.g., of iron and copper) homeostasis. In several diseases, including cancer, this balance is disturbed. Therefore, anticancer drugs targeting the redox systems, for example, glutathione and thioredoxin, have entered focus of interest. Anticancer metal complexes (platinum, gold, arsenic, ruthenium, rhodium, copper, vanadium, cobalt, manganese, gadolinium, and molybdenum) have been shown to strongly interact with or even disturb cellular redox homeostasis. In this context, especially the hypothesis of “activation by reduction” as well as the “hard and soft acids and bases” theory with respect to coordination of metal ions to cellular ligands represent important concepts to understand the molecular modes of action of anticancer metal drugs. The aim of this review is to highlight specific interactions of metal-based anticancer drugs with the cellular redox homeostasis and to explain this behavior by considering chemical properties of the respective anticancer metal complexes currently either in (pre)clinical development or in daily clinical routine in oncology. PMID:21275772

  1. 45 CFR 1177.4 - Claims involving criminal activity or misconduct.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...indebtedness involves criminal activity such as fraud, embezzlement, theft, or misuse of government funds or property is subject to punishment by fine or imprisonment as well as to a civil claim by the United States for compensation for the misappropriated...

  2. 5 CFR 1215.24 - Claims involving criminal activity or misconduct.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...indebtedness involves criminal activity such as fraud, embezzlement, theft, or misuse of government funds or property is subject to punishment by fine or imprisonment as well as to a civil claim by the United States for compensation for the misappropriated...

  3. 5 CFR 1215.24 - Claims involving criminal activity or misconduct.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...indebtedness involves criminal activity such as fraud, embezzlement, theft, or misuse of government funds or property is subject to punishment by fine or imprisonment as well as to a civil claim by the United States for compensation for the misappropriated...

  4. 76 FR 76935 - Impact of Implementing the Chemical Weapons Convention (CWC) on Commercial Activities Involving...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-09

    ...111130706-1686-01] Impact of Implementing the Chemical Weapons Convention (CWC) on Commercial...Activities Involving ``Schedule 1'' Chemicals Through Calendar Year 2011; Impact...Salts of CWC ``Schedule 1'' Chemicals to ``Schedule 1;''...

  5. 75 FR 69630 - Impact of Implementation of the Chemical Weapons Convention on Commercial Activities Involving...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-15

    ...101103543-0543-02] Impact of Implementation of the Chemical Weapons Convention on Commercial Activities Involving ``Schedule 1'' Chemicals, Including Production of Schedule 1 Chemicals as Intermediates, Through Calendar Year 2010...

  6. 24 CFR 1000.501 - Who is involved in monitoring activities under NAHASDA?

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...CONTINUED) OFFICE OF ASSISTANT SECRETARY FOR PUBLIC AND INDIAN HOUSING, DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT NATIVE AMERICAN HOUSING ACTIVITIES Recipient Monitoring, Oversight and Accountability § 1000.501 Who is involved in...

  7. Health benefits of serious involvement in leisure activities among older Korean adults

    PubMed Central

    Kim, Junhyoung; Yamada, Naoko; Heo, Jinmoo; Han, Areum

    2014-01-01

    The existing literature suggests that serious engagement in leisure activities leads to happiness, life satisfaction, and successful aging among older adults. This qualitative study was used to examine the benefits of serious involvement in leisure activities among older Korean adults who were members of a sports club. Using an analytic data analysis, we identified three main themes associated with the benefits of serious engagement in leisure activities: 1) the experience of psychological benefits, 2) the creation of social support, and 3) the enhancement of physical health. These themes indicate that, through serious involvement in certain physical activities, participants gain various health benefits, which may contribute to successful aging. PMID:25059979

  8. Molecular genetic analysis of activation-tagged transcription factors thought to be involved in photomorphogenesis

    SciTech Connect

    Neff, Michael M.

    2011-06-23

    This is a final report for Department of Energy Grant No. DE-FG02-08ER15927 entitled “Molecular Genetic Analysis of Activation-Tagged Transcription Factors Thought to be Involved in Photomorphogenesis”. Based on our preliminary photobiological and genetic analysis of the sob1-D mutant, we hypothesized that OBP3 is a transcription factor involved in both phytochrome and cryptochrome-mediated signal transduction. In addition, we hypothesized that OBP3 is involved in auxin signaling and root development. Based on our preliminary photobiological and genetic analysis of the sob2-D mutant, we also hypothesized that a related gene, LEP, is involved in hormone signaling and seedling development.

  9. Involvement of tissue plasminogen activator in stress responsivity during acute cocaine withdrawal in mice

    E-print Network

    Involvement of tissue plasminogen activator in stress responsivity during acute cocaine withdrawal to stress responsivity during cocaine withdrawal (WD). Recent studies suggest that tissue plasminogen activator (tPA) in the CeA is a downstream effector protein for CRF after acute "binge" cocaine

  10. Signaling Complexes and Protein-Protein Interactions Involved in the Activation of the Ras and Phosphatidylinositol

    E-print Network

    Ibáñez, Carlos

    on the oncogenic potential of the c-ret gene, leading to the develop- ment of several types of cancers, includingSignaling Complexes and Protein-Protein Interactions Involved in the Activation of the Ras activation of Ras by GDNF. Phosphorylation of Erk kinases was also greatly atten- uated but not eliminated

  11. 15 CFR 712.1 - Round to zero rule that applies to activities involving Schedule 1 chemicals.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...to activities involving Schedule 1 chemicals. 712.1 Section 712.1 Commerce...SECURITY, DEPARTMENT OF COMMERCE CHEMICAL WEAPONS CONVENTION REGULATIONS ACTIVITIES INVOLVING SCHEDULE 1 CHEMICALS § 712.1 Round to zero...

  12. 15 CFR 712.1 - Round to zero rule that applies to activities involving Schedule 1 chemicals.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...to activities involving Schedule 1 chemicals. 712.1 Section 712.1 Commerce...SECURITY, DEPARTMENT OF COMMERCE CHEMICAL WEAPONS CONVENTION REGULATIONS ACTIVITIES INVOLVING SCHEDULE 1 CHEMICALS § 712.1 Round to zero...

  13. 30 CFR 57.4660 - Work in shafts, raises, or winzes and other activities involving hazard areas.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...other activities involving hazard areas. 57.4660 Section 57...Welding/cutting/compressed Gases § 57.4660 Work in shafts...activities involving hazard areas. During performance of...taken: (1) Wet down the area before and after the...

  14. Addressing Three Common Issues in Research on Youth Activities: An Integrative Approach for Operationalizing and Analyzing Involvement

    ERIC Educational Resources Information Center

    Busseri, Michael A.; Rose-Krasnor, Linda

    2010-01-01

    Youth activity involvement has been operationalized and analyzed using a wide range of approaches. Researchers face the challenges of distinguishing between the effects of involvement versus noninvolvement and intensity of involvement in a particular activity, accounting simultaneously for cumulative effects of involvement, and addressing multiple…

  15. Platelet-activating factor (PAF) involvement in acetaminophen-induced liver toxicity and regeneration

    Microsoft Academic Search

    A. D. Grypioti; S. E. Theocharis; G. K. Papadimas; C. A. Demopoulos; Z. Papadopoulou-Daifoti; A. C. Basayiannis; M. G. Mykoniatis

    2005-01-01

    Acetaminophen-induced toxicity has been attributed to cytochrome P-450-generated metabolites, which covalently modify target proteins. However, the mechanism of liver injury pathogenesis needs to be further elucidated. Platelet-activating factor (PAF) is one of the mediators involved in inflammatory tissue alterations associated with acute liver failure. In this study, alterations in blood PAF levels and the serum activity of PAF-acetylhydrolase (PAF-AH) were

  16. Involvement of thrombin and mitogen-activated protein kinase pathways in hemorrhagic brain injury

    Microsoft Academic Search

    Masatoshi Ohnishi; Hiroshi Katsuki; Shinji Fujimoto; Mikako Takagi; Toshiaki Kume; Akinori Akaike

    2007-01-01

    Thrombin is thought to play an important role in brain damage associated with intracerebral hemorrhage (ICH). We previously showed that activation of mitogen-activated protein (MAP) kinases and recruitment of microglia are crucial for thrombin-induced shrinkage of the striatal tissue in vitro and thrombin-induced striatal damage in vivo. Here we investigated whether the same mechanisms are involved in ICH-induced brain injury.

  17. Carbohydrate in the mouth enhances activation of brain circuitry involved in motor performance and sensory perception.

    PubMed

    Turner, Clare E; Byblow, Winston D; Stinear, Cathy M; Gant, Nicholas

    2014-09-01

    The presence of carbohydrate in the human mouth has been associated with the facilitation of motor output and improvements in physical performance. Oral receptors have been identified as a potential mode of afferent transduction for this novel form of nutrient signalling that is distinct from taste. In the current study oral exposure to carbohydrate was combined with a motor task in a neuroimaging environment to identify areas of the brain involved in this phenomenon. A mouth-rinsing protocol was conducted whilst carbohydrate (CHO) and taste-matched placebo (PLA) solutions were delivered and recovered from the mouths of 10 healthy volunteers within a double-blind, counterbalanced design. This protocol eliminates post-oral factors and controls for the perceptual qualities of solutions. Functional magnetic resonance imaging of the brain was used to identify cortical areas responsive to oral carbohydrate during rest and activity phases of a hand-grip motor task. Mean blood-oxygen-level dependent signal change experienced in the contralateral primary sensorimotor cortex was larger for CHO compared with PLA during the motor task when contrasted with a control condition. Areas of activation associated with CHO exclusively were observed over the primary taste cortex and regions involved in visual perception. Regions in the limbic system associated with reward were also significantly more active with CHO. This is the first demonstration that oral carbohydrate signalling can increase activation within the primary sensorimotor cortex during physical activity and enhance activation of neural networks involved in sensory perception. PMID:24858834

  18. Involving Your Child or Teen with ASD in Integrated Community Activities

    ERIC Educational Resources Information Center

    McKee, Rebecca

    2011-01-01

    Participating in outside activities and community-based endeavors can be tricky for people with special needs, like Autism Spectrum Disorder (ASD). Families meet more than a few obstacles attempting to integrate their children or teens who have special needs like ASD. Most typical children are highly involved in sports, clubs and camps. If a…

  19. A Longitudinal Examination of Breadth and Intensity of Youth Activity Involvement and Successful Development

    ERIC Educational Resources Information Center

    Busseri, Michael A.; Rose-Krasnor, Linda; Willoughby, Teena; Chalmers, Heather

    2006-01-01

    Connections between youth activity involvement and indicators of successful development were examined in a longitudinal high school sample. Drawing on theories of expertise skill development (e.g., J. Cote, 1999); the selection, optimization, and compensation framework (P. B. Baltes, 1997); and theories of positive youth development (e.g., R. M.…

  20. Magnesium Ion-dependent Activation of the RecA Protein Involves the C Terminus*

    E-print Network

    Cox, Michael M.

    Magnesium Ion-dependent Activation of the RecA Protein Involves the C Terminus* Received with ATP. We provide evi- dence that the free magnesium ion is required to medi- ate a conformational at low magnesium ion concentrations. The RecA protein of Escherichia coli plays a central role

  1. Beyond the Classroom: Involving Students with Disabilities in Extracurricular Activities at Levy Middle School.

    ERIC Educational Resources Information Center

    Walker, Pam; And Others

    Six students in a special education classroom at Levy Middle School (Syracuse, New York) became involved in a variety of after-school activities with nondisabled students. The students participated in the school computer club, cross-country skiing, volleyball, stage crew, intramural basketball, the Spanish Club, and after-school programs at two…

  2. Increasing Parent Involvement in the Learning Activities of Intermediate (Grades 4-6) Students.

    ERIC Educational Resources Information Center

    Tomlinson, Ancelyn E.

    Conducted in a school serving mainly Hispanic children, this practicum implemented an intervention designed to increase parents' involvement in the learning activities of their children. Practicum goals were to: (1) increase parents' attendance at Parent Teacher Association (PTA) meetings; (2) increase parents' attendance at parent-teacher…

  3. Longitudinal Modeling of Adolescents' Activity Involvement, Problem Peer Associations, and Youth Smoking

    ERIC Educational Resources Information Center

    Metzger, Aaron; Dawes, Nickki; Mermelstein, Robin; Wakschlag, Lauren

    2011-01-01

    Longitudinal associations among different types of organized activity involvement, problem peer associations, and cigarette smoking were examined in a sample of 1040 adolescents (mean age = 15.62 at baseline, 16.89 at 15-month assessment, 17.59 at 24 months) enriched for smoking experimentation (83% had tried smoking). A structural equation model…

  4. Perceived community environment and physical activity involvement in a northern-rural Aboriginal community

    Microsoft Academic Search

    Allison M. Kirby; Lucie Lévesque; Virginia Wabano; Jennifer Robertson-Wilson

    2007-01-01

    BACKGROUND: Type 2 diabetes disproportionately affects Aboriginal peoples in Canada. Ample evidence shows that regular physical activity (PA) plays an important role in the prevention and treatment of type 2 diabetes. Evidence is beginning to emerge linking PA to the physical environment but little is known about the relationship between remote rural environments and PA involvement in Aboriginal peoples. This

  5. An Emergent Language Program Framework: Actively Involving Learners in Needs Analysis.

    ERIC Educational Resources Information Center

    Savage, William; Storer, Graeme

    1992-01-01

    Relates the experience of the staff of an aquaculture outreach program in Northeast Thailand in implementing an English for special purposes program. By actively involving learners in both the needs analysis and program design, teachers were able to adapt the program content to the requirements of the students. (15 references) (JL)

  6. Beyond Participation: The Association between School Extracurricular Activities and Involvement in Violence across Generations of Immigration

    ERIC Educational Resources Information Center

    Jiang, Xin; Peterson, Ruth D.

    2012-01-01

    Participation in extracurricular activities is purported to protect the broad spectrum of youth from a host of behavioral risks. Yet, empirical research on the extent to which this assumption holds for involvement in violence by immigrant youth is limited. Thus, using data for 13,236 (51.8% female) adolescents from the National Longitudinal Study…

  7. Involving Children in Health and Social Research: "Human Becomings" or "Active Beings"?

    ERIC Educational Resources Information Center

    Balen, Rachel; Blyth, Eric; Calabretto, Helen; Fraser, Claire; Horrocks, Christine; Manby, Martin

    2006-01-01

    This article draws on the authors' experiences of undertaking health and social research involving children in Australia and England and focuses on securing the informed consent of children to participate in such research. A clear trend within literature, service provision, legislation and international conventions recognizes children as "active

  8. Calanquinone A induces anti-glioblastoma activity through glutathione-involved DNA damage and AMPK activation

    PubMed Central

    Liu, Fan-Lun; Hsu, Jui-Ling; Lee, Yean-Jang; Dong, Yu-Shun; Kung, Fan-Lu; Chen, Ching-Shih; Guh, Jih-Hwa

    2014-01-01

    Glioblastoma, a highly malignant glioma, is resistant to both radiation and chemotherapy and is an intractable problem in clinical treatment. New therapeutic approaches are in urgent need. Calanquinone A, an herbal constituent, displayed anti-proliferative activity against glioblastoma cells, including A172, T98 and U87. Flow cytometric analysis showed an S phase arrest and a subsequent apoptosis to calanquinone A action. Further identification demonstrated a rapid increase of ?H2A.X formation at S phase. The data together with comet tail formation and Chk1 activation indicated DNA damage response. N-acetyl cysteine (an antioxidant and a glutathione precursor) and exogenously applied glutathione, but not trolox (an antioxidant), completely abolished calanquinone A-induced effects. Immunofluorescence assay revealed that calanquinone A decreased the intracellular glutathione levels in both A172 and T98 cells. However, calanquinone A, by itself, did not conjugate glutathione. The data suggested that the decrease of cellular glutathione predominantly contributed to the anticancer mechanism. Furthermore, calanquinone A induced the activation of AMP-activated protein kinase (AMPK) and the inhibition of p70S6K activity. Rhodamine efflux assay showed that calanquinone A did not block efflux activity, indicating that calanquinone A was not a P-glycoprotein substrate. In summary, the data suggest that calanquinone A displays anti-glioblastoma activity through a decrease of cellular glutathione levels that subsequently induces DNA damage stress and AMPK activation, leading to cell cycle arrest at S-phase and apoptotic cell death. Furthermore, calanquinone A does not serve as a P-glycoprotein substrate, suggesting a potential for further development in anti-glioblastoma therapy. PMID:24607408

  9. Parental involvement in school activities in South Africa to the mutual benefit of the school and the community

    Microsoft Academic Search

    Vusi Mncube

    2010-01-01

    This article reports on an investigation into parental involvement in school activities. The study employed the quantitative approach of data collection, using a questionnaire comprising a profile of respondents, which included their parental involvement in school activities, their satisfaction with the school, their knowledge of legal rights and responsibilities and their involvement with, and concern about, their children's education. The

  10. Properties of aminopeptidase activity involved in the conversion of vasopressin by rat brain membranes.

    PubMed

    Burbach, J P; De Bree, F M; Terwel, D; Tan, A; Maskova, H P; Van der Kleij, A A

    1993-01-01

    Previously it has been shown that vasopressin (VP) and oxytocin are converted by aminopeptidase activity in brain membranes into fragments with potent CNS activities. This report concerns the properties of this enzyme activity, addressed as VP-converting aminopeptidase (VP-AP) activity, in membranes of the rat brain. The VP-AP activity had a pH optimum at pH 7.0 and had a Km of 17 microM for its action on VP. Amastatin was the most potent aminopeptidase inhibitor. Enzyme activity was inhibited by relatively low concentrations of metal chelators. Treatment of brain membranes by EDTA resulted in loss of enzyme activity that was completely reversed by 10 microM Zn2+, indicating that VP-AP activity is a metallopeptidase. Several VP analogues and fragments, in particular VP(1-8), inhibited the action of enzyme activity on VP. Among peptides unrelated to VP, angiotension I, somatostatin, and porcine ACTH(1-39) markedly inhibited enzyme activity. Solubilization of VP-AP activity from brain membranes and gel filtration on Sephadex G200 showed two peaks of activity, one eluting with an apparent mass of about 140 kDa, the other in the void volume. Gel filtration fractions were able to convert [3H][Phe3]VP in a step-wise fashion. The VP-AP-like activity was found in many tissues outside the brain. Highest activity was present in lung, kidney, parts of the gastrointestinal tract, ovary, and uterus. The results indicate that VP-AP activity is a widely distributed enzyme with probably multiple functions, one of which involves the metabolism of vasopressin in the brain. PMID:7993391

  11. Mechanism of IL-1? Modulation of Intestinal Epithelial Barrier Involves p38 Kinase and Activating Transcription Factor-2 Activation

    PubMed Central

    Al-Sadi, Rana; Guo, Shuhong; Ye, Dongmei; Dokladny, Karol; Alhmoud, Tarik; Ereifej, Lisa; Said, Hamid M.

    2013-01-01

    The defective intestinal epithelial tight junction (TJ) barrier has been postulated to be an important pathogenic factor contributing to intestinal inflammation. It has been shown that the proinflammatory cytokine IL-1? causes an increase in intestinal permeability; however, the signaling pathways and the molecular mechanisms involved remain unclear. The major purpose of this study was to investigate the role of the p38 kinase pathway and the molecular processes involved. In these studies, the in vitro intestinal epithelial model system (Caco-2 monolayers) was used to delineate the cellular and molecular mechanisms, and a complementary in vivo mouse model system (intestinal perfusion) was used to assess the in vivo relevance of the in vitro findings. Our data indicated that the IL-1? increase in Caco-2 TJ permeability correlated with an activation of p38 kinase. The activation of p38 kinase caused phosphorylation and activation of p38 kinase substrate, activating transcription factor (ATF)-2. The activated ATF-2 translocated to the nucleus where it attached to its binding motif on the myosin L chain kinase (MLCK) promoter region, leading to the activation of MLCK promoter activity and gene transcription. Small interfering RNA induced silencing of ATF-2, or mutation of the ATF-2 binding motif prevented the activation of MLCK promoter and MLCK mRNA transcription. Additionally, in vivo intestinal perfusion studies also indicated that the IL-1? increase in mouse intestinal permeability required p38 kinase–dependent activation of ATF-2. In conclusion, these studies show that the IL-1?–induced increase in intestinal TJ permeability in vitro and in vivo was regulated by p38 kinase activation of ATF-2 and by ATF-2 regulation of MLCK gene activity. PMID:23656735

  12. Oclacitinib (APOQUEL®) is a novel Janus kinase inhibitor with activity against cytokines involved in allergy

    PubMed Central

    Gonzales, A J; Bowman, J W; Fici, G J; Zhang, M; Mann, D W; Mitton-Fry, M

    2014-01-01

    Janus kinase (JAK) enzymes are involved in cell signaling pathways activated by various cytokines dysregulated in allergy. The objective of this study was to determine whether the novel JAK inhibitor oclacitinib could reduce the activity of cytokines implicated in canine allergic skin disease. Using isolated enzyme systems and in vitro human or canine cell models, potency and selectivity of oclacitinib was determined against JAK family members and cytokines that trigger JAK activation in cells. Oclacitinib inhibited JAK family members by 50% at concentrations (IC50's) ranging from 10 to 99 nm and did not inhibit a panel of 38 non-JAK kinases (IC50's > 1000 nm). Oclacitinib was most potent at inhibiting JAK1 (IC50 = 10 nm). Oclacitinib also inhibited the function of JAK1-dependent cytokines involved in allergy and inflammation (IL-2, IL-4, IL-6, and IL-13) as well as pruritus (IL-31) at IC50's ranging from 36 to 249 nm. Oclacitinib had minimal effects on cytokines that did not activate the JAK1 enzyme in cells (erythropoietin, granulocyte/macrophage colony-stimulating factor, IL-12, IL-23; IC50's > 1000 nm). These results demonstrate that oclacitinib is a targeted therapy that selectively inhibits JAK1-dependent cytokines involved in allergy, inflammation, and pruritus and suggests these are the mechanisms by which oclacitinib effectively controls clinical signs associated with allergic skin disease in dogs. PMID:24495176

  13. Acoustic input and efferent activity regulate the expression of molecules involved in cochlear micromechanics.

    PubMed

    Lamas, Veronica; Arévalo, Juan C; Juiz, José M; Merchán, Miguel A

    2014-01-01

    Electromotile activity in auditory outer hair cells (OHCs) is essential for sound amplification. It relies on the highly specialized membrane motor protein prestin, and its interactions with the cytoskeleton. It is believed that the expression of prestin and related molecules involved in OHC electromotility may be dynamically regulated by signals from the acoustic environment. However little is known about the nature of such signals and how they affect the expression of molecules involved in electromotility in OHCs. We show evidence that prestin oligomerization is regulated, both at short and relatively long term, by acoustic input and descending efferent activity originating in the cortex, likely acting in concert. Unilateral removal of the middle ear ossicular chain reduces levels of trimeric prestin, particularly in the cochlea from the side of the lesion, whereas monomeric and dimeric forms are maintained or even increased in particular in the contralateral side, as shown in Western blots. Unilateral removal of the auditory cortex (AC), which likely causes an imbalance in descending efferent activity on the cochlea, also reduces levels of trimeric and tetrameric forms of prestin in the side ipsilateral to the lesion, whereas in the contralateral side prestin remains unaffected, or even increased in the case of trimeric and tetrameric forms. As far as efferent inputs are concerned, unilateral ablation of the AC up-regulates the expression of ?10 nicotinic Ach receptor (nAChR) transcripts in the cochlea, as shown by RT-Quantitative real-time PCR (qPCR). This suggests that homeostatic synaptic scaling mechanisms may be involved in dynamically regulating OHC electromotility by medial olivocochlear efferents. Limited, unbalanced efferent activity after unilateral AC removal, also affects prestin and ?-actin mRNA levels. These findings support that the concerted action of acoustic and efferent inputs to the cochlea is needed to regulate the expression of major molecules involved in OHC electromotility, both at the transcriptional and posttranscriptional levels. PMID:25653600

  14. Platelet-Activating Factor Involvement in Thioacetamide-Induced Experimental Liver Fibrosis and Cirrhosis

    Microsoft Academic Search

    Haralabos C. Karantonis; Georgios Gribilas; Ioannis Stamoulis; Constantinos Giaginis; Chara Spiliopoulou; Gregorios Kouraklis; Constantinos Demopoulos; Stamatios E. Theocharis

    2010-01-01

    Platelet-activating factor (PAF) is a potent lipid inflammatory mediator acting on cells through its specific receptor. Plasma\\u000a PAF-acetylhydrolase (PAF-AH) is the main enzyme that inactivates PAF in blood, participating in its homeostasis. The objective\\u000a of this study was to investigate the involvement of PAF in the liver fibrotic process using an experimental animal model.\\u000a Liver fibrosis was induced in adult

  15. Structural parts involved in activation and inactivation of the sodium channel

    Microsoft Academic Search

    Walter Stühmer; Franco Conti; Harukazu Suzuki; Xiaodong Wang; Masaharu Noda; Naoki Yahagi; Hideo Kubo; Shosaku Numa

    1989-01-01

    Structure-function relationships of the sodium channel expressed inXenopus oocytes have been investigated by the combined use of site-directed mutagenesis and patch-clamp recording. This study provides evidence that the positive charges in segment S4 are involved in the voltage-sensing mechanism for activation of the channel and that the region between repeats III and IV is important for its inactivation.

  16. Mechanisms involved in VPAC receptors activation and regulation: lessons from pharmacological and mutagenesis studies.

    PubMed

    Langer, Ingrid

    2012-01-01

    Vasoactive intestinal peptide (VIP) plays diverse and important role in human physiology and physiopathology and their receptors constitute potential targets for the treatment of several diseases such as neurodegenerative disorder, asthma, diabetes, and inflammatory diseases. This article reviews the current knowledge regarding the two VIP receptors, VPAC(1) and VPAC(2), with respect to mechanisms involved in receptor activation, G protein coupling, signaling, regulation, and oligomerization. PMID:23115557

  17. Acoustic input and efferent activity regulate the expression of molecules involved in cochlear micromechanics

    PubMed Central

    Lamas, Veronica; Arévalo, Juan C.; Juiz, José M.; Merchán, Miguel A.

    2015-01-01

    Electromotile activity in auditory outer hair cells (OHCs) is essential for sound amplification. It relies on the highly specialized membrane motor protein prestin, and its interactions with the cytoskeleton. It is believed that the expression of prestin and related molecules involved in OHC electromotility may be dynamically regulated by signals from the acoustic environment. However little is known about the nature of such signals and how they affect the expression of molecules involved in electromotility in OHCs. We show evidence that prestin oligomerization is regulated, both at short and relatively long term, by acoustic input and descending efferent activity originating in the cortex, likely acting in concert. Unilateral removal of the middle ear ossicular chain reduces levels of trimeric prestin, particularly in the cochlea from the side of the lesion, whereas monomeric and dimeric forms are maintained or even increased in particular in the contralateral side, as shown in Western blots. Unilateral removal of the auditory cortex (AC), which likely causes an imbalance in descending efferent activity on the cochlea, also reduces levels of trimeric and tetrameric forms of prestin in the side ipsilateral to the lesion, whereas in the contralateral side prestin remains unaffected, or even increased in the case of trimeric and tetrameric forms. As far as efferent inputs are concerned, unilateral ablation of the AC up-regulates the expression of ?10 nicotinic Ach receptor (nAChR) transcripts in the cochlea, as shown by RT-Quantitative real-time PCR (qPCR). This suggests that homeostatic synaptic scaling mechanisms may be involved in dynamically regulating OHC electromotility by medial olivocochlear efferents. Limited, unbalanced efferent activity after unilateral AC removal, also affects prestin and ?-actin mRNA levels. These findings support that the concerted action of acoustic and efferent inputs to the cochlea is needed to regulate the expression of major molecules involved in OHC electromotility, both at the transcriptional and posttranscriptional levels. PMID:25653600

  18. Involvement of NADPH oxidases in suppression of cyclooxygenase-2 promoter-dependent transcriptional activities by sesamol

    PubMed Central

    Shimizu, Satomi; Ishigamori, Rikako; Fujii, Gen; Takahashi, Mami; Onuma, Wakana; Terasaki, Masaru; Yano, Tomohiro; Mutoh, Michihiro

    2015-01-01

    Cyclooxygenase-2 (COX-2) has been shown to play an important role in colon carcinogenesis. Moreover, one of the components of reduced nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, NADPH oxidase 1 (NOX1), dominantly expressed in the colon, is implicated in the pathogenesis of colon cancer. We have reported that sesamol, one of the lignans in sesame seeds, suppressed COX-2 gene transcriptional activity in human colon cancer cells, and also suppressed intestinal polyp formation in Apc-mutant mice. In the present study, we investigated the involvement of NADPH oxidase in the inhibition of COX-2 transcriptional activity by sesamol. We found that several NADPH oxidase inhibitors, such as apocynin, showed suppressive effects on COX-2 transcriptional activity. Moreover, sesamol significantly suppressed NOX1 mRNA levels in a dose-dependent manner. In addition, we demonstrated that knockdown of NOX1 successfully suppressed COX-2 transcriptional activity. These results suggest that inhibition of NADPH oxidase, especially NOX1, may be involved in the mechanism of the suppression of COX-2 transcriptional activity by sesamol. PMID:25759517

  19. Involvement of NADPH oxidases in suppression of cyclooxygenase-2 promoter-dependent transcriptional activities by sesamol.

    PubMed

    Shimizu, Satomi; Ishigamori, Rikako; Fujii, Gen; Takahashi, Mami; Onuma, Wakana; Terasaki, Masaru; Yano, Tomohiro; Mutoh, Michihiro

    2015-03-01

    Cyclooxygenase-2 (COX-2) has been shown to play an important role in colon carcinogenesis. Moreover, one of the components of reduced nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, NADPH oxidase 1 (NOX1), dominantly expressed in the colon, is implicated in the pathogenesis of colon cancer. We have reported that sesamol, one of the lignans in sesame seeds, suppressed COX-2 gene transcriptional activity in human colon cancer cells, and also suppressed intestinal polyp formation in Apc-mutant mice. In the present study, we investigated the involvement of NADPH oxidase in the inhibition of COX-2 transcriptional activity by sesamol. We found that several NADPH oxidase inhibitors, such as apocynin, showed suppressive effects on COX-2 transcriptional activity. Moreover, sesamol significantly suppressed NOX1 mRNA levels in a dose-dependent manner. In addition, we demonstrated that knockdown of NOX1 successfully suppressed COX-2 transcriptional activity. These results suggest that inhibition of NADPH oxidase, especially NOX1, may be involved in the mechanism of the suppression of COX-2 transcriptional activity by sesamol. PMID:25759517

  20. Aluminum Hydroxide Adjuvant Differentially Activates the Three Complement Pathways with Major Involvement of the Alternative Pathway

    PubMed Central

    Güven, Esin; Duus, Karen; Laursen, Inga; Højrup, Peter; Houen, Gunnar

    2013-01-01

    Al(OH)3 is the most common adjuvant in human vaccines, but its mode of action remains poorly understood. Complement involvement in the adjuvant properties of Al(OH)3 has been suggested in several reports together with a depot effect. It is here confirmed that Al(OH)3 treatment of serum depletes complement components and activates the complement system. We show that complement activation by Al(OH)3 involves the three major pathways by monitoring complement components in Al(OH)3-treated serum and in Al(OH)3-containing precipitates. Al(OH)3 activation of complement results in deposition of C3 cleavage products and membrane attack complex (MAC) and in generation of the anaphylatoxins C3a and C5a. Complement activation was time dependent and inhibited by chelation with EDTA but not EGTA+Mg2+. We thus confirm that Al(OH)3 activates the complement system and show that the alternative pathway is of major importance. PMID:24040248

  1. Tocotrienols activity in MCF-7 breast cancer cells: involvement of ERbeta signal transduction.

    PubMed

    Comitato, Raffaella; Leoni, Guido; Canali, Raffaella; Ambra, Roberto; Nesaretnam, Kalanithi; Virgili, Fabio

    2010-05-01

    The term Vitamin E is utilized to describe eight molecules, subdivided into two groups, tocopherols and tocotrienols (TTs). It has been shown that specific TTs affect the growth of several lines of tumour cells, and that this activity is not shared by tocopherols. In agreement with these observations, a TTs-rich fraction from palm oil (PTRF) was reported to inhibit proliferation and induce apoptosis in several cancer cells. However, the molecular mechanism involved in TTs activity is still unclear. We have recently proposed that TTs pro-apoptotic activity involves estrogen receptor beta (ERbeta) signalling. In this study, we report that, in MCF-7 breast cancer cell, expressing both ERalpha and ERbeta, PTRF treatment increases ERbeta nuclear translocation, as demonstrated by immunofluorescence experiments and significantly inhibits ERalpha expression (-458.91-fold of change) and complete disappearing of the protein from the nucleus. Moreover, PTRF treatment induces ER-dependent genes expression (macrophage inhibitory cytokine-1, early growth response-1 and Cathepsin D) which is inhibited by the ER inhibitor, ICI 182.780, and induces DNA fragmentation. Finally, cDNA-array experiments suggest that the activation of specific pathways in cells treated with gamma-TT with respect to alpha-TT. Our data suggest a novel potential molecular mechanism for TTs activity. PMID:20306477

  2. HTLV-1 Tax-mediated TAK1 activation involves TAB2 adapter protein

    SciTech Connect

    Yu Qingsheng; Minoda, Yasumasa; Yoshida, Ryoko; Yoshida, Hideyuki [Division of Molecular and Cellular Immunology, Medical Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, Fukuoka 812-8582 (Japan); Iha, Hidekatsu [Department of Infectious Diseases, Faculty of Medicine, Oita University, Yufu, Oita 879-5593 (Japan); Kobayashi, Takashi; Yoshimura, Akihiko [Division of Molecular and Cellular Immunology, Medical Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, Fukuoka 812-8582 (Japan); Takaesu, Giichi [Division of Molecular and Cellular Immunology, Medical Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, Fukuoka 812-8582 (Japan)], E-mail: takaesug@bioreg.kyushu-u.ac.jp

    2008-01-04

    Human T cell leukemia virus type 1 (HTLV-1) Tax is an oncoprotein that plays a crucial role in the proliferation and transformation of HTLV-1-infected T lymphocytes. It has recently been reported that Tax activates a MAPKKK family, TAK1. However, the molecular mechanism of Tax-mediated TAK1 activation is not well understood. In this report, we investigated the role of TAK1-binding protein 2 (TAB2) in Tax-mediated TAK1 activation. We found that TAB2 physically interacts with Tax and augments Tax-induced NF-{kappa}B activity. Tax and TAB2 cooperatively activate TAK1 when they are coexpressed. Furthermore, TAK1 activation by Tax requires TAB2 binding as well as ubiquitination of Tax. We also found that the overexpression of TRAF2, 5, or 6 strongly induces Tax ubiquitination. These results suggest that TAB2 may be critically involved in Tax-mediated activation of TAK1 and that NF-{kappa}B-activating TRAF family proteins are potential cellular E3 ubiquitin ligases toward Tax.

  3. Enterobacter-Activated Mosquito Immune Responses to Plasmodium Involve Activation of SRPN6 in Anopheles stephensi

    PubMed Central

    Jacobs-Lorena, Marcelo

    2013-01-01

    Successful development of Plasmodium in the mosquito is essential for the transmission of malaria. A major bottleneck in parasite numbers occurs during midgut invasion, partly as a consequence of the complex interactions between the endogenous microbiota and the mosquito immune response. We previously identified SRPN6 as an immune component which restricts Plasmodium berghei development in the mosquito. Here we demonstrate that SRPN6 is differentially activated by bacteria in Anopheles stephensi, but only when bacteria exposure occurs on the lumenal surface of the midgut epithelium. Our data indicate that AsSRPN6 is strongly induced following exposure to Enterobacter cloacae, a common component of the mosquito midgut microbiota. We conclude that AsSRPN6 is a vital component of the E. cloacae-mediated immune response that restricts Plasmodium development in the mosquito An. stephensi. PMID:23658788

  4. Enterobacter-activated mosquito immune responses to Plasmodium involve activation of SRPN6 in Anopheles stephensi.

    PubMed

    Eappen, Abraham G; Smith, Ryan C; Jacobs-Lorena, Marcelo

    2013-01-01

    Successful development of Plasmodium in the mosquito is essential for the transmission of malaria. A major bottleneck in parasite numbers occurs during midgut invasion, partly as a consequence of the complex interactions between the endogenous microbiota and the mosquito immune response. We previously identified SRPN6 as an immune component which restricts Plasmodium berghei development in the mosquito. Here we demonstrate that SRPN6 is differentially activated by bacteria in Anopheles stephensi, but only when bacteria exposure occurs on the lumenal surface of the midgut epithelium. Our data indicate that AsSRPN6 is strongly induced following exposure to Enterobacter cloacae, a common component of the mosquito midgut microbiota. We conclude that AsSRPN6 is a vital component of the E. cloacae-mediated immune response that restricts Plasmodium development in the mosquito An. stephensi. PMID:23658788

  5. Extinction of tyrosine aminotransferase gene activity in somatic cell hybrids involves modification and loss of several essential transcriptional activators.

    PubMed

    Nitsch, D; Boshart, M; Schütz, G

    1993-02-01

    Extinction is defined as the loss of cell type-specific gene expression that occurs in somatic cell hybrids derived by fusion of cells with dissimilar phenotypes. To explore the basis of this dominant-negative regulation, we have studied the activities of the control elements of the liver-specific gene encoding tyrosine aminotransferase (TAT) in hepatoma/fibroblast hybrid crosses. We show that extinction in complete somatic cell hybrids is accompanied by the loss of activity of all known cell type-specific control elements of the TAT gene. This inactivity is the result of first, lack of expression of genes coding for the transcriptional activators HNF4 and HNF3 beta and HNF3 gamma, which bind to essential elements of the enhancers; and second, loss of in vivo binding and activity of ubiquitous factors to these enhancers, including CREB, which is the target for repression by the tissue-specific extinguisher locus TSE1. Complete extinction of TAT gene activity is therefore a multifactorial process affecting all three enhancers controlling liver-specific and hormone-inducible expression. It results from lack of activation, rather than active repression, and involves both post-translational modification and loss of essential transcriptional activators. PMID:8094701

  6. Forest soil metagenome gene cluster involved in antifungal activity expression in Escherichia coli.

    PubMed

    Chung, Eu Jin; Lim, He Kyoung; Kim, Jin-Cheol; Choi, Gyung Ja; Park, Eun Jin; Lee, Myung Hwan; Chung, Young Ryun; Lee, Seon-Woo

    2008-02-01

    Using two forest soils, we previously constructed two fosmid libraries containing 113,700 members in total. The libraries were screened to select active antifungal clones using Saccharomyces cerevisiae as a target fungus. One clone from the Yuseong pine tree rhizosphere soil library, pEAF66, showed S. cerevisiae growth inhibition. Despite an intensive effort, active chemicals were not isolated. DNA sequence analysis and transposon mutagenesis of pEAF66 revealed 39 open reading frames (ORFs) and indicated that eight ORFs, probably in one transcriptional unit, might be directly involved in the expression of antifungal activity in Escherichia coli. The deduced amino acid sequences of eight ORFs were similar to those of the core genes encoding type II family polyketide synthases, such as the acyl carrier protein (ACP), ACP synthases, aminotransferase, and ACP reductase. The gene cluster involved in antifungal activity was similar in organization to the putative antibiotic production locus of Pseudomonas putida KT2440, although we could not select a similar active clone from the KT2440 genomic DNA library in E. coli. ORFs encoding ATP binding cassette transporters and membrane proteins were located at both ends of the antifungal gene cluster. Upstream ORFs encoding an IclR family response regulator and a LysR family response regulator were involved in the positive regulation of antifungal gene expression. Our results suggested the metagenomic approach as an alternative to search for novel antifungal antibiotics from unculturable soil bacteria. This is the first report of an antifungal gene cluster obtained from a soil metagenome using S. cerevisiae as a target fungus. PMID:18065615

  7. Involvement of the SATB1/F-actin complex in chromatin reorganization during active cell death.

    PubMed

    Grzanka, Dariusz; Gagat, Maciej; Izdebska, Magdalena

    2014-06-01

    Over the past years, confirmations on the presence of actin and/or its polymerized form, F-actin, in the cell nucleus are progressively accumulating. Nevertheless, the function and localization of F-actin in the nucleus is still not fully characterized. Thus, the aim of the present study was to evaluate the association between F-actin and sequence-binding protein 1 (SATB1) and their involvement in chromatin remodeling associated with active cell death. Both SATB1 and F-actin were colocalized in the transcriptional active regions of the cell nucleus and a functional interaction was observed between SATB1 and higher-organized nuclear F-actin structures at the border between condensed and decondensed chromatin. These results extend the knowledge on the role of SATB1 and nuclear F-actin in three-dimensional chromatin organization and their functions during active cell death. Additionally, this study opens the discussion on the involvement of the SATB1/F-actin functional complex in active cell death; further studies are required to fully elucidate these issues. PMID:24676287

  8. Antinociceptive Activity of Methanol Extract of Muntingia calabura Leaves and the Mechanisms of Action Involved.

    PubMed

    Sani, M H Mohd; Zakaria, Z A; Balan, T; Teh, L K; Salleh, M Z

    2012-01-01

    Muntingia calabura L. (family Elaeocarpaceae) has been traditionally used to relieve various pain-related ailments. The present study aimed to determine the antinociceptive activity of methanol extract of M. calabura leaves (MEMC) and to elucidate the possible mechanism of antinociception involved. The in vivo chemicals (acetic acid-induced abdominal constriction and formalin-, capsaicin-, glutamate-, serotonin-induced paw licking test) and thermal (hot plate test) models of nociception were used to evaluate the extract antinociceptive activity. The extract (100, 250, and 500?mg/kg) was administered orally 60?min prior to subjection to the respective test. The results obtained demonstrated that MEMC produced significant (P < 0.05) antinociceptive response in all the chemical- and thermal-induced nociception models, which was reversed after pretreatment with 5?mg/kg naloxone, a non-selective opioid antagonist. Furthermore, pretreatment with L-arginine (a nitric oxide (NO) donor), N(G)-nitro-L-arginine methyl esters (L-NAME; an inhibitor of NO synthase (NOS)), methylene blue (MB; an inhibitor of cyclic-guanosine monophosphate (cGMP) pathway), or their combination also caused significant (P < 0.05) change in the intensity of the MEMC antinociception. In conclusion, the MEMC antinociceptive activity involves activation of the peripheral and central mechanisms, and modulation via, partly, the opioid receptors and NO/cGMP pathway. PMID:22611437

  9. Involvement of the SATB1/F-actin complex in chromatin reorganization during active cell death

    PubMed Central

    GRZANKA, DARIUSZ; GAGAT, MACIEJ; IZDEBSKA, MAGDALENA

    2014-01-01

    Over the past years, confirmations on the presence of actin and/or its polymerized form, F-actin, in the cell nucleus are progressively accumulating. Nevertheless, the function and localization of F-actin in the nucleus is still not fully characterized. Thus, the aim of the present study was to evaluate the association between F-actin and sequence-binding protein 1 (SATB1) and their involvement in chromatin remodeling associated with active cell death. Both SATB1 and F-actin were colocalized in the transcriptional active regions of the cell nucleus and a functional interaction was observed between SATB1 and higher-organized nuclear F-actin structures at the border between condensed and decondensed chromatin. These results extend the knowledge on the role of SATB1 and nuclear F-actin in three-dimensional chromatin organization and their functions during active cell death. Additionally, this study opens the discussion on the involvement of the SATB1/F-actin functional complex in active cell death; further studies are required to fully elucidate these issues. PMID:24676287

  10. Antinociceptive Activity of Methanol Extract of Muntingia calabura Leaves and the Mechanisms of Action Involved

    PubMed Central

    Sani, M. H. Mohd.; Zakaria, Z. A.; Balan, T.; Teh, L. K.; Salleh, M. Z.

    2012-01-01

    Muntingia calabura L. (family Elaeocarpaceae) has been traditionally used to relieve various pain-related ailments. The present study aimed to determine the antinociceptive activity of methanol extract of M. calabura leaves (MEMC) and to elucidate the possible mechanism of antinociception involved. The in vivo chemicals (acetic acid-induced abdominal constriction and formalin-, capsaicin-, glutamate-, serotonin-induced paw licking test) and thermal (hot plate test) models of nociception were used to evaluate the extract antinociceptive activity. The extract (100, 250, and 500?mg/kg) was administered orally 60?min prior to subjection to the respective test. The results obtained demonstrated that MEMC produced significant (P < 0.05) antinociceptive response in all the chemical- and thermal-induced nociception models, which was reversed after pretreatment with 5?mg/kg naloxone, a non-selective opioid antagonist. Furthermore, pretreatment with L-arginine (a nitric oxide (NO) donor), NG-nitro-L-arginine methyl esters (L-NAME; an inhibitor of NO synthase (NOS)), methylene blue (MB; an inhibitor of cyclic-guanosine monophosphate (cGMP) pathway), or their combination also caused significant (P < 0.05) change in the intensity of the MEMC antinociception. In conclusion, the MEMC antinociceptive activity involves activation of the peripheral and central mechanisms, and modulation via, partly, the opioid receptors and NO/cGMP pathway. PMID:22611437

  11. An Initial Investigation of Sexual Minority Youth Involvement in School-Based Extracurricular Activities

    PubMed Central

    Russell, Stephen T.

    2012-01-01

    Sexual minority youth are at risk for negative school-based experiences and poor academic outcomes. Yet, little is known about their experiences in positive school-based contexts. Using the National Longitudinal Study of Adolescent Health (1,214 sexual minority and 11,427 heterosexual participants), this study compared participation rates in, predictors of, and outcomes associated with three types of school-based extracurricular activities - sports, arts, and school clubs - by sexual orientation and gender. Findings revealed several significant sexual orientation and gender differences in participation rates in school-based sports, clubs, and arts activities. Further, findings suggested that the outcomes associated with extracurricular activity involvement do not differ by sexual orientation and gender; however, predictors of participation in these domains varied across groups. PMID:24187476

  12. An Initial Investigation of Sexual Minority Youth Involvement in School-Based Extracurricular Activities.

    PubMed

    Toomey, Russell B; Russell, Stephen T

    2013-06-01

    Sexual minority youth are at risk for negative school-based experiences and poor academic outcomes. Yet, little is known about their experiences in positive school-based contexts. Using the National Longitudinal Study of Adolescent Health (1,214 sexual minority and 11,427 heterosexual participants), this study compared participation rates in, predictors of, and outcomes associated with three types of school-based extracurricular activities - sports, arts, and school clubs - by sexual orientation and gender. Findings revealed several significant sexual orientation and gender differences in participation rates in school-based sports, clubs, and arts activities. Further, findings suggested that the outcomes associated with extracurricular activity involvement do not differ by sexual orientation and gender; however, predictors of participation in these domains varied across groups. PMID:24187476

  13. Involvement of loops 2 and 3 of ?-sarcin on its ribotoxic activity.

    PubMed

    Castaño-Rodríguez, Carlos; Olombrada, Miriam; Partida-Hanon, Angélica; Lacadena, Javier; Oñaderra, Mercedes; Gavilanes, José G; García-Ortega, Lucía; Martínez-Del-Pozo, Álvaro

    2015-03-01

    Ribotoxins are a family of fungal ribosome-inactivating proteins displaying highly specific ribonucleolytic activity against the sarcin/ricin loop (SRL) of the larger rRNA, with ?-sarcin as its best-characterized member. Their toxicity arises from the combination of this activity with their ability to cross cell membranes. The involvement of ?-sarcin's loops 2 and 3 in SRL and ribosomal proteins recognition, as well as in the ribotoxin-lipid interactions involving cell penetration, has been suggested some time ago. In the work presented now different mutants have been prepared in order to study the role of these loops in their ribonucleolytic and lipid-interacting properties. The results obtained confirm that loop 3 residues Lys 111, 112, and 114 are key actors of the specific recognition of the SRL. In addition, it is also shown that Lys 114 and Tyr 48 conform a network of interactions which is essential for the catalysis. Lipid-interaction studies show that this Lys-rich region is indeed involved in the phospholipids recognition needed to cross cell membranes. Loop 2 is shown to be responsible for the conformational change which exposes the region establishing hydrophobic interactions with the membrane inner leaflets and eases penetration of ribotoxins target cells. PMID:25598497

  14. The benefits of in-group contact through physical activity involvement for health and well-being among Korean immigrants

    PubMed Central

    Kim, Junhyoung; Heo, Jinmoo; Kim, Jun

    2014-01-01

    This qualitative study is designed to examine the benefits of physical activity involvement with members of the same ethnic group. For this study, Korean immigrants who were members of Korean physical activity clubs such as badminton and tennis were selected as participants. Using a constructive grounded theory methodology, three themes were identified as benefits of physical activity involvement: (1) the experience of psychological well-being, (2) the creation of a unique cultural world, and (3) the facilitation of physical activity involvement. The findings of this study suggest that Korean immigrant participants gained various social, cultural, and psychological benefits by engaging in activities with other Korean immigrants. PMID:24875239

  15. The benefits of in-group contact through physical activity involvement for health and well-being among Korean immigrants.

    PubMed

    Kim, Junhyoung; Heo, Jinmoo; Kim, Jun

    2014-01-01

    This qualitative study is designed to examine the benefits of physical activity involvement with members of the same ethnic group. For this study, Korean immigrants who were members of Korean physical activity clubs such as badminton and tennis were selected as participants. Using a constructive grounded theory methodology, three themes were identified as benefits of physical activity involvement: (1) the experience of psychological well-being, (2) the creation of a unique cultural world, and (3) the facilitation of physical activity involvement. The findings of this study suggest that Korean immigrant participants gained various social, cultural, and psychological benefits by engaging in activities with other Korean immigrants. PMID:24875239

  16. Alternative activation of human plasmacytoid DCs in vitro and in melanoma lesions: involvement of LAG-3.

    PubMed

    Camisaschi, Chiara; De Filippo, Annamaria; Beretta, Valeria; Vergani, Barbara; Villa, Antonello; Vergani, Elisabetta; Santinami, Mario; Cabras, Antonello Domenico; Arienti, Flavio; Triebel, Frédéric; Rodolfo, Monica; Rivoltini, Licia; Castelli, Chiara

    2014-07-01

    Plasmacytoid dendritic cells (pDCs) at tumor sites are often tolerogenic. Although pDCs initiate innate and adaptive immunity upon Toll-like receptor (TLR) triggering by pathogens, TLR-independent signals may be responsible for pDC activation and immune suppression in the tumor inflammatory environment. To identify molecules that are potentially involved in alternative pDC activation, we explored the expression and function of lymphocyte activation gene 3 (LAG-3) in human pDCs. In this report, we showed the expression of LAG-3 on the cell surface of a subset of circulating human pDCs. LAG-3+ pDCs exhibited a partially mature phenotype and were enriched at tumor sites in samples from melanoma patients. We found that LAG-3 interacted with major histocompatibility complex class II (MHC-II) to induce TLR-independent activation of pDCs with limited IFN? and enhanced IL-6 production. This in vitro cytokine profile of LAG-3-activated pDCs paralleled that of tumor-associated pDCs analyzed ex vivo. By confocal microscopy, LAG-3+ pDCs detected in melanoma-invaded lymph nodes (LNs) stained positive for IL-6 and preferentially localized near melanoma cells. These results suggest that LAG-3-mediated activation of pDCs takes place in vivo at tumor sites, and it is in part responsible for directing an immune-suppressive environment. PMID:24441096

  17. Structure and activity of regulatory elements involved in the activation of the Hoxd-11 gene during late gastrulation.

    PubMed Central

    Gérard, M; Duboule, D; Zákány, J

    1993-01-01

    We have used reporter gene constructs to study the cis regulation of the Hoxd-11 gene (previously Hox-4.6) in transgenic mice. We identified a 5 kb regulatory unit, which was able to reproduce important aspects of the initial activation of the gene along the major body axis. The comparison of the nucleotide sequence of this DNA fragment with the corresponding avian genomic region revealed the presence of seven highly homologous stretches of DNA outside the protein coding regions. In particular, the 3' flanking region contained two such domains that are required to mediate the embryonic activation. A chimeric construct containing the two short homologous regions from the chicken gene could replace the complete murine fragment thus demonstrating that the conserved domains carry the main regulatory elements involved in this activation. The first half of this bipartite regulatory region has enhancer activity when tested with a heterologous promoter, while the second half is required to restrict the enhancer activity to the proper expression domain. These results suggest that stage- and tissue-specific cooperation between regulatory elements is required to control properly the activity of the Hoxd-11 promoter. Images PMID:7902810

  18. INVOLVEMENT OF GLIAL ACTIVATION IN TRIGEMINAL GANGLION IN A RAT MODEL OF LOWER GINGIVAL CANCER PAIN

    PubMed Central

    HIRONAKA, KATSUNORI; OZAKI, NORIYUKI; HATTORI, HISASHI; NAGAMINE, KENJIRO; NAKASHIMA, HIDEYUKI; UEDA, MINORU; SUGIURA, YASUO

    2014-01-01

    ABSTRACT Glial cells were investigated to elucidate their involvement in mechanisms underlying oral cancer pain. Squamous cell carcinoma (SCC-158) was inoculated into the lower gingiva of male Fisher rats. Pharmacological and immunohistochemical studies were performed to examine the roles played by TRPV1 and TRPV2 expressed in neurons and satellite glia in trigeminal ganglia (TG), and microglia and astrocytes in trigeminal spinal nucleus caudalis. Inoculation of SCC-158 into the lower gingiva induced marked mechanical allodynia in the whisker-pad skin area on days 16 through 28, and in the submandibular skin area on days 10 through 20. Cutaneous allodynia was diminished by systemic morphine administration. The number of TRPV1 and TRPV2-positive neurons in trigeminal ganglia increased in the medium and large cell groups on day 14 after tumor inoculation. The number of satellite glial cells encircling the medium and large trigeminal ganglion neurons increased on day 28 after tumor inoculation. In this gingival cancer pain model, microglia and astrocytes in trigeminal spinal nucleus caudalis were not activated, although they were reported to be activated in neuropathic and inflammatory pain models. These results suggest that TRPV1 and TRPV2 upregulation in trigeminal ganglion neurons may play an important role in inducing the mechanical allodynia observed in experimental models of oral squamous cell carcinoma. In addition, activation of satellite cells seems to be involved in the maintenance of mechanical allodynia, which could be the potential therapeutic target for oral cancer pain. PMID:25741041

  19. Zebrafish reporter lines reveal in vivo signaling pathway activities involved in pancreatic cancer

    PubMed Central

    Schiavone, Marco; Rampazzo, Elena; Casari, Alessandro; Battilana, Giusy; Persano, Luca; Moro, Enrico; Liu, Shu; Leach, Steve D.; Tiso, Natascia; Argenton, Francesco

    2014-01-01

    Pancreatic adenocarcinoma, one of the worst malignancies of the exocrine pancreas, is a solid tumor with increasing incidence and mortality in industrialized countries. This condition is usually driven by oncogenic KRAS point mutations and evolves into a highly aggressive metastatic carcinoma due to secondary gene mutations and unbalanced expression of genes involved in the specific signaling pathways. To examine in vivo the effects of KRASG12D during pancreatic cancer progression and time correlation with cancer signaling pathway activities, we have generated a zebrafish model of pancreatic adenocarcinoma in which eGFP-KRASG12D expression was specifically driven to the pancreatic tissue by using the GAL4/UAS conditional expression system. Outcrossing the inducible oncogenic KRASG12D line with transgenic zebrafish reporters, harboring specific signaling responsive elements of transcriptional effectors, we were able to follow TGF?, Notch, Bmp and Shh activities during tumor development. Zebrafish transgenic lines expressing eGFP-KRASG12D showed normal exocrine pancreas development until 3 weeks post fertilization (wpf). From 4 to 24 wpf we observed several degrees of acinar lesions, characterized by an increase in mesenchymal cells and mixed acinar/ductal features, followed by progressive bowel and liver infiltrations and, finally, highly aggressive carcinoma. Moreover, live imaging analysis of the exocrine pancreatic tissue revealed an increasing number of KRAS-positive cells and progressive activation of TGF? and Notch pathways. Increase in TGF?, following KRASG12D activation, was confirmed in a concomitant model of medulloblastoma (MDB). Notch and Shh signaling activities during tumor onset were different between MDB and pancreatic adenocarcinoma, indicating a tissue-specific regulation of cell signaling pathways. Moreover, our results show that a living model of pancreatic adenocarcinoma joined with cell signaling reporters is a suitable tool for describing in vivo the signaling cascades and molecular mechanisms involved in tumor development and a potential platform to screen for novel oncostatic drugs. PMID:24878567

  20. Aesthetic activities and aesthetic attitudes: Influences of education, background and personality on interest and involvement in the arts

    Microsoft Academic Search

    I. C. McManus; A. Furnham

    2006-01-01

    There have been few studies of why some people are frequently involved in aesthetic activities such as going to the theatre, reading or playing musical instruments, whereas others are less involved. This study assesses the broad roles of education, personality and demographic factors such as social class, age and sex. More aesthetic activity was associated with music and art education,

  1. Longitudinal relationships between perceived stress, exercise self-regulation and exercise involvement among physically active adolescents.

    PubMed

    Gerber, Markus; Lindwall, Magnus; Brand, Serge; Lang, Christin; Elliot, Catherine; Pühse, Uwe

    2015-01-01

    Stress exposure may undermine exercisers' capability to self-regulate their exercise behaviour. This longitudinal study examined the interplay between perceived stress, exercise self-regulation (assessment of action and coping planning) and participation in vigorous exercise in vocational students. Moreover, this study examined whether high exercise self-regulation moderates the assumed negative relationship between stress and exercise. A sample of 580 physically active vocational students ([Formula: see text] ± s 17.8 ± 1.3 years, 33.8% girls) was assessed. All participants completed two identical validated questionnaires assessing stress, exercise self-regulation and exercise with a span of 10 months in between survey completion periods. The cross-sectional analyses show that high exercise self-regulation attenuated the assumed negative relationship between stress and exercise. In the longitudinal analyses, however, only a non-significant trend was found. Significant longitudinal relationships existed between exercise self-regulation and exercise involvement. Latent difference score models revealed that a drop in the exercise self-regulation was associated with a concurrent decrease in exercise participation. Cross-lagged panel analyses showed that high exercise self-regulation levels positively predicted exercise behaviour, but an inverse relationship was not supported. The findings suggested that higher exercise self-regulation levels were positively associated with future exercise involvement in currently active adolescents. While partial support was found that exercise self-regulation moderated the influence of stress on exercise, the findings demonstrated that higher exercise self-regulation levels had a positive impact on future exercise involvement in already active individuals. PMID:25098842

  2. Lipopolysaccharide-induced lung injury involves the nitration-mediated activation of RhoA.

    PubMed

    Rafikov, Ruslan; Dimitropoulou, Christiana; Aggarwal, Saurabh; Kangath, Archana; Gross, Christine; Pardo, Daniel; Sharma, Shruti; Jezierska-Drutel, Agnieszka; Patel, Vijay; Snead, Connie; Lucas, Rudolf; Verin, Alexander; Fulton, David; Catravas, John D; Black, Stephen M

    2014-02-21

    Acute lung injury (ALI) is characterized by increased endothelial hyperpermeability. Protein nitration is involved in the endothelial barrier dysfunction in LPS-exposed mice. However, the nitrated proteins involved in this process have not been identified. The activation of the small GTPase RhoA is a critical event in the barrier disruption associated with LPS. Thus, in this study we evaluated the possible role of RhoA nitration in this process. Mass spectroscopy identified a single nitration site, located at Tyr(34) in RhoA. Tyr(34) is located within the switch I region adjacent to the nucleotide-binding site. Utilizing this structure, we developed a peptide designated NipR1 (nitration inhibitory peptide for RhoA 1) to shield Tyr(34) against nitration. TAT-fused NipR1 attenuated RhoA nitration and barrier disruption in LPS-challenged human lung microvascular endothelial cells. Further, treatment of mice with NipR1 attenuated vessel leakage and inflammatory cell infiltration and preserved lung function in a mouse model of ALI. Molecular dynamics simulations suggested that the mechanism by which Tyr(34) nitration stimulates RhoA activity was through a decrease in GDP binding to the protein caused by a conformational change within a region of Switch I, mimicking the conformational shift observed when RhoA is bound to a guanine nucleotide exchange factor. Stopped flow kinetic analysis was used to confirm this prediction. Thus, we have identified a new mechanism of nitration-mediated RhoA activation involved in LPS-mediated endothelial barrier dysfunction and show the potential utility of "shielding" peptides to prevent RhoA nitration in the management of ALI. PMID:24398689

  3. Getting involved in international development activities: UK initiatives and hidden benefits.

    PubMed

    Cheeseborough, Jackie; Godbolt, Shane; Grant, Maria J

    2015-03-01

    Jackie Cheeseborough and Shane Godbolt describe the role that UK health information professionals have in global health and in supporting colleagues from developing countries to continue to develop as a provision. They give an overview of a range of organisations working to improve access to health information in developing countries and in particular Sub-Saharan Africa including Book Aid International, HIFA, INASP, ITOCA, Phi, TALC, THET and Research4Life. Even in a recession, many UK health librarians are choosing to get involved in international development activities in low-resource countries by volunteering, and discovering hidden benefits for their own organisations, and their own continuing professional development. PMID:25684025

  4. GSK3? signaling is involved in ultraviolet B-induced activation of autophagy in epidermal cells

    PubMed Central

    YANG, YANG; WANG, HAIPING; WANG, SIYING; XU, MEI; LIU, MEI; LIAO, MINGJUN; FRANK, JACQUELINE A.; ADHIKARI, SABAL; BOWER, KIMBERLY A.; SHI, XIANGLIN; MA, CUILING; LUO, JIA

    2012-01-01

    Ultraviolet B (UVB) exposure causes damage to skin and represents the primary etiological agent for skin cancer formation. UVB induces DNA damage and apoptosis in epidermal cells. In this study, we demonstrated that UVB activated autophagy in JB6 epidermal cells, which was evident by the formation of LC3 puncta, the induction of LC3 lipidation, the increase in beclin 1 expression, and the decrease in the levels of p62. Autophagy appeared to be a protective response to UVB-induced damage because inhibition of autophagy exacerbated UVB-induced cell death, and stimulation of autophagy offered protection. Furthermore, we demonstrated that glycogen synthase kinase 3? (GSK3?) was involved in UVB-induced autophagy. UVB inhibited GSK3? activation by simultaneously enhancing phosphorylation at Ser9 and suppressing Tyr216 phosphorylation. GSK3? negatively regulated autophagy; overexpression of wild-type or S9A (constitutive-active) GSK3? mutant inhibited UVB-mediated autophagy, while overexpression of a dominant-negative K85R mutant enhanced UVB-mediated autophagy. Inhibition of GSK3? also offered protection against UVB-mediated damage. UVB activated AMP-activated protein kinase (AMPK), an important regulator of autophagy through the inhibition of GSK3?. Taken together, our results suggest that UVB-stimulated autophagy is a protective response for epidermal cells and is mediated by the GSK3?/AMPK pathway. PMID:22961228

  5. GSK3? signaling is involved in ultraviolet B-induced activation of autophagy in epidermal cells.

    PubMed

    Yang, Yang; Wang, Haiping; Wang, Siying; Xu, Mei; Liu, Mei; Liao, Mingjun; Frank, Jacqueline A; Adhikari, Sabal; Bower, Kimberly A; Shi, Xianglin; Ma, Cuiling; Luo, Jia

    2012-11-01

    Ultraviolet B (UVB) exposure causes damage to skin and represents the primary etiological agent for skin cancer formation. UVB induces DNA damage and apoptosis in epidermal cells. In this study, we demonstrated that UVB activated autophagy in JB6 epidermal cells, which was evident by the formation of LC3 puncta, the induction of LC3 lipidation, the increase in beclin 1 expression, and the decrease in the levels of p62. Autophagy appeared to be a protective response to UVB-induced damage because inhibition of autophagy exacerbated UVB-induced cell death, and stimulation of autophagy offered protection. Furthermore, we demonstrated that glycogen synthase kinase 3? (GSK3?) was involved in UVB-induced autophagy. UVB inhibited GSK3? activation by simultaneously enhancing phosphorylation at Ser9 and suppressing Tyr216 phosphorylation. GSK3? negatively regulated autophagy; overexpression of wild?type or S9A (constitutive-active) GSK3? mutant inhibited UVB-mediated autophagy, while overexpression of a dominant-negative K85R mutant enhanced UVB-mediated autophagy. Inhibition of GSK3? also offered protection against UVB-mediated damage. UVB activated AMP-activated protein kinase (AMPK), an important regulator of autophagy through the inhibition of GSK3?. Taken together, our results suggest that UVB-stimulated autophagy is a protective response for epidermal cells and is mediated by the GSK3?/AMPK pathway. PMID:22961228

  6. Inhibition of Fast Axonal Transport by Pathogenic SOD1 Involves Activation of p38 MAP Kinase

    PubMed Central

    Morfini, Gerardo A.; Bosco, Daryl A.; Brown, Hannah; Gatto, Rodolfo; Kaminska, Agnieszka; Song, Yuyu; Molla, Linda; Baker, Lisa; Marangoni, M. Natalia; Berth, Sarah; Tavassoli, Ehsan; Bagnato, Carolina; Tiwari, Ashutosh; Hayward, Lawrence J.; Pigino, Gustavo F.; Watterson, D. Martin; Huang, Chun-Fang; Banker, Gary; Brown, Robert H.; Brady, Scott T.

    2013-01-01

    Dying-back degeneration of motor neuron axons represents an established feature of familial amyotrophic lateral sclerosis (FALS) associated with superoxide dismutase 1 (SOD1) mutations, but axon-autonomous effects of pathogenic SOD1 remained undefined. Characteristics of motor neurons affected in FALS include abnormal kinase activation, aberrant neurofilament phosphorylation, and fast axonal transport (FAT) deficits, but functional relationships among these pathogenic events were unclear. Experiments in isolated squid axoplasm reveal that FALS-related SOD1 mutant polypeptides inhibit FAT through a mechanism involving a p38 mitogen activated protein kinase pathway. Mutant SOD1 activated neuronal p38 in mouse spinal cord, neuroblastoma cells and squid axoplasm. Active p38 MAP kinase phosphorylated kinesin-1, and this phosphorylation event inhibited kinesin-1. Finally, vesicle motility assays revealed previously unrecognized, isoform-specific effects of p38 on FAT. Axon-autonomous activation of the p38 pathway represents a novel gain of toxic function for FALS-linked SOD1 proteins consistent with the dying-back pattern of neurodegeneration characteristic of ALS. PMID:23776455

  7. NRF2 activation is involved in ozonated human serum upregulation of HO-1 in endothelial cells

    SciTech Connect

    Pecorelli, Alessandra [Department of Molecular and Developmental Medicine, University of Siena (Italy); Child Neuropsychiatry Unit, University Hospital, AOUS, Siena (Italy); Bocci, Velio [Department of Physiology, University of Siena (Italy); Acquaviva, Alessandra [Department of Molecular and Developmental Medicine, University of Siena (Italy); Belmonte, Giuseppe [Department of Biomedical Sciences, University of Siena (Italy); Gardi, Concetta [Department of Molecular and Developmental Medicine, University of Siena (Italy); Virgili, Fabio [INRAN, Rome (Italy); Ciccoli, Lucia [Department of Molecular and Developmental Medicine, University of Siena (Italy); Valacchi, Giuseppe, E-mail: giuseppe.valacchi@unife.it [Department of Life Sciences and Biotechnology, University of Ferrara (Italy); Department of Food and Nutrition, Kyung Hee University, Seoul (Korea, Republic of)

    2013-02-15

    During the last decade, it has been shown that the activation of NRF2 and the binding to electrophile-responsive element (EpREs), stimulates the expression of a great number of genes responsible for the synthesis of phase I and phase II proteins, including antioxidants enzymes and heme oxygenase-1 (HO-1). This critical cell response occurs in cardiovascular, degenerative and chronic infective diseases aggravated by a chronic oxidative stress. In our previous reports we have shown that ozonated plasma is able to up-regulate HO-1 expression in endothelial cells. In the present work we investigated a candidate mechanism involved in this process. After treatment with increasing doses of ozonated serum (20, 40 and 80 ?g/mL O{sub 3} per mL of serum), a clear dose dependent activation of NRF2 and the subsequent induction of HO-1 and NAD(P)H quinone oxidoreductase 1(NQO1) was observed. This effect was also present when cells were treated with serum and hydrogen peroxide (H{sub 2}O{sub 2}) or serum and 4-hydroxynonenal (4HNE). Moreover, the treatment with ozonated serum was associated with a dose-dependent activation of extracellular-signal-regulated kinases (ERK1/2) and p38 MAP kinases (p38), not directly involved in NRF2 activation. These data, provide a new insight on the mechanism responsible for the induction of HO-1 expression by ozonated serum in the endothelium, and have a practical importance as an expedient approach to the treatment of patients with both effective orthodox drugs and ozonated autohemotherapy, targeted to the restoration of redox homeostasis. - Highlights: ? Endothelial HO1 is upregulated by ozonated plasma ? This activation is induced by NRF2 and it is ERK independent. ? 4HNE and H{sub 2}O{sub 2} are the main molecules involved in this process. ? Ozonated plasma induced a hormetic effect ? Combination of orthodox medicine and ozonated plasma can be a useful treatment.

  8. Antidepressant-like activity of dehydrozingerone: involvement of the serotonergic and noradrenergic systems.

    PubMed

    Martinez, Débora M; Barcellos, Angelita; Casaril, Angela M; Savegnago, Lucielli; Lernardão, Eder J

    2014-12-01

    Dehydrozingerone (DHZ) is a phenolic compound isolated from ginger rhizomes (Zingiber officinale). It is known for its diverse spectrum of biological activities as an antioxidant, anti-inflammatory and antitumor compound. The present study was designed to assess the antidepressant effect of DHZ and the involvement of the monoaminergic system and to evaluate its in vitro antioxidant activity in the hippocampus, cortex and cerebellum of mice. For this study, the tail suspension test (TST), forced swim test (FST) and yohimbine lethality test were performed. DHZ administered orally 30min prior to testing reduced the immobility time in the TST (1-40mg/kg) and the FST (10-40mg/kg), with no change in locomotor activity in the open field test. The antidepressant-like effect of DHZ (1mg/kg) was prevented by ketanserin (1mg/kg, i.p.; a 5-HT2A/2C receptor antagonist), ondansetron (1mg/kg, i.p.; a 5-HT3 receptor antagonist), prazosin (1mg/kg, i.p., an ?1-adrenoceptor antagonist) and yohimbine (1mg/kg, i.p., an ?2-adrenoceptor antagonist) pretreatments. Furthermore, DHZ administered at doses of 10 and 20mg/kg increased the lethality of yohimbine (35mg/kg, i.p.). DHZ had antioxidant activity on in vitro lipid peroxidation induced by sodium nitroprusside in all brain regions tested. The results revealed that DHZ has a potent antidepressant effect, which seems to involve the serotonergic and noradrenergic systems. PMID:25449795

  9. Trabecular bone remodelling under pathological conditions based on biochemical and mechanical processes involved in BMU activity.

    PubMed

    Liotier, P J; Rossi, J M; Wendling-Mansuy, S; Chabrand, P

    2013-01-01

    In adulthood, bone tissue is continuously renewed by processes governed by basic multicellular units composed of osteocytes, osteoclasts and osteoblasts, which are subjected to local mechanical loads. Osteocytes are known to be integrated mechanosensors that regulate the activation of the osteoclasts and osteoblasts involved in bone resorption and apposition processes, respectively. After collagen tissue apposition, a process of collagen mineralisation takes place, gradually increasing the effective stiffness of bone. This study presents a new model based on physicochemical parameters involved in spongy bone remodelling under pathological conditions. Our model simulates the transient evolution of both geometry and effective Young's modulus of the trabeculae, also taking turnover into account. Various loads were applied on a trabecula in order to determine the evolution of bone volume fraction under pathological conditions. A parametric study performed on the model showed that one key parameter here is the kinetic constant of hydroxyapatite crystallisation. We subsequently tested our model on a pathological case approaching osteoporosis, involving a decrease in the number of viable osteocytes present in bone. The model converges to a lower value (- 5%) for bone volume fraction than with a normal quantity of osteocytes. This useful tool offers new perspectives for predicting bone remodelling deficits on a local scale in patients with pathological conditions such as osteoporosis and in bedridden patients, as well as for astronauts subjected to weightlessness in space. PMID:22289038

  10. Involvement of a phospholipase C in the hemolytic activity of a clinical strain of Pseudomonas fluorescens

    PubMed Central

    Rossignol, Gaelle; Merieau, Annabelle; Guerillon, Josette; Veron, Wilfried; Lesouhaitier, Olivier; Feuilloley, Marc GJ; Orange, Nicole

    2008-01-01

    Background Pseudomonas fluorescens is a ubiquitous Gram-negative bacterium frequently encountered in hospitals as a contaminant of injectable material and surfaces. This psychrotrophic bacterium, commonly described as unable to grow at temperatures above 32°C, is now considered non pathogenic. We studied a recently identified clinical strain of P. fluorescens biovar I, MFN1032, which is considered to cause human lung infection and can grow at 37°C in laboratory conditions. Results We found that MFN1032 secreted extracellular factors with a lytic potential at least as high as that of MF37, a psychrotrophic strain of P. fluorescens or the mesophilic opportunistic pathogen, Pseudomonas aeruginosa PAO1. We demonstrated the direct, and indirect – through increases in biosurfactant release – involvement of a phospholipase C in the hemolytic activity of this bacterium. Sequence analysis assigned this phospholipase C to a new group of phospholipases C different from those produced by P. aeruginosa. We show that changes in PlcC production have pleiotropic effects and that plcC overexpression and plcC extinction increase MFN1032 toxicity and colonization, respectively. Conclusion This study provides the first demonstration that a PLC is involved in the secreted hemolytic activity of a clinical strain of Pseudomonas fluorescens. Moreover, this phospholipase C seems to belong to a complex biological network associated with the biosurfactant production. PMID:18973676

  11. Internalization of Clostridium perfringens ?-toxin leads to ERK activation and is involved on its cytotoxic effect.

    PubMed

    Monturiol-Gross, Laura; Flores-Díaz, Marietta; Campos-Rodríguez, Diana; Mora, Rodrigo; Rodríguez-Vega, Mariela; Marks, David L; Alape-Girón, Alberto

    2014-04-01

    Clostridium perfringens phospholipase C (CpPLC), also called ?-toxin, plays a key role in the pathogenesis of gas gangrene. CpPLC may lead to cell lysis at concentrations that cause extensive degradation of plasma membrane phospholipids. However, at sublytic concentrations it induces cytotoxicity without inducing evident membrane damage. The results of this work demonstrate that CpPLC becomes internalized in cells by a dynamin-dependent mechanism and in a time progressive process: first, CpPLC colocalizes with caveolin both at the plasma membrane and in vesicles, and later it colocalizes with early and late endosomes and lysosomes. Lysosomal damage in the target cells is evident 9?h after CpPLC exposure. Our previous work demonstrated that CpPLCinduces ERK1/2 activation, which is involved in its cytotoxic effect. In this work we found that cholesterol sequestration, dynamin inhibition, as well as inhibition of actin polymerization, prevent CpPLC internalization and ERK1/2 activation, involving endocytosis in the signalling events required for CpPLC cytotoxic effect at sublytic concentrations. These results provide new insights about the mode of action of this bacterial phospholipase C, previously considered to act only locally on cell membrane. PMID:24245664

  12. Who's who in the crew? Exploring participant involvement in the Active Living Coalition.

    PubMed

    Barnes, Priscilla A; Schaefer, Samantha; Middlestadt, Susan; Knoblock, Heidi

    2015-06-01

    Health coalitions serve as an important "vehicle" to strengthen horizontal and vertical ties between organizations, community groups, and individuals whose intent and purpose is to improve wellness. Having a strong and diverse group of participants is essential for highly effective coalitions to carry out their mission in an organized and participatory manner. However, the extent that individuals become involved in coalition operations and activities remains ambiguous. A grounded theory approach was used to explore expressions of participant involvement of a local health coalition known as the Active Living Coalition (ALC). Open, axial, as well as domain and taxonomic coding were used to analyze transcripts from four focus groups (n=37 participants) in order to develop a participant continuum that captured six network aggregates within the coalition. Findings suggest that participation, for the most part, was heterogeneous and ever-changing given the expectations of the level of partnership that best individuals' personal and professional interests. Differentiating the type of participants in health coalitions can help coalition leaders more successfully "manage" new and existing relationships. Findings imply that health coalitions can maximize coalition capacity by drawing upon the full range of potential human and material resources by further understanding the types of individuals that make up their network. PMID:25812479

  13. Developmental changes in brain activation involved in the production of novel speech sounds in children.

    PubMed

    Hashizume, Hiroshi; Taki, Yasuyuki; Sassa, Yuko; Thyreau, Benjamin; Asano, Michiko; Asano, Kohei; Takeuchi, Hikaru; Nouchi, Rui; Kotozaki, Yuka; Jeong, Hyeonjeong; Sugiura, Motoaki; Kawashima, Ryuta

    2014-08-01

    Older children are more successful at producing unfamiliar, non-native speech sounds than younger children during the initial stages of learning. To reveal the neuronal underpinning of the age-related increase in the accuracy of non-native speech production, we examined the developmental changes in activation involved in the production of novel speech sounds using functional magnetic resonance imaging. Healthy right-handed children (aged 6-18 years) were scanned while performing an overt repetition task and a perceptual task involving aurally presented non-native and native syllables. Productions of non-native speech sounds were recorded and evaluated by native speakers. The mouth regions in the bilateral primary sensorimotor areas were activated more significantly during the repetition task relative to the perceptual task. The hemodynamic response in the left inferior frontal gyrus pars opercularis (IFG pOp) specific to non-native speech sound production (defined by prior hypothesis) increased with age. Additionally, the accuracy of non-native speech sound production increased with age. These results provide the first evidence of developmental changes in the neural processes underlying the production of novel speech sounds. Our data further suggest that the recruitment of the left IFG pOp during the production of novel speech sounds was possibly enhanced due to the maturation of the neuronal circuits needed for speech motor planning. This, in turn, would lead to improvement in the ability to immediately imitate non-native speech. PMID:24585739

  14. Mitochondrial Dysfunction Is Involved in the Toxic Activity of Boric Acid against Saprolegnia

    PubMed Central

    Ali, Shimaa E.; Thoen, Even; Evensen, Øystein; Wiik-Nielsen, Jannicke; Gamil, Amr A. A.; Skaar, Ida

    2014-01-01

    There has been a significant increase in the incidence of Saprolegnia infections over the past decades, especially after the banning of malachite green. Very often these infections are associated with high economic losses in salmonid farms and hatcheries. The use of boric acid to control the disease has been investigated recently both under in vitro and in vivo conditions, however its possible mode of action against fish pathogenic Saprolegnia is not known. In this study, we have explored the transformation in Saprolegnia spores/hyphae after exposure to boric acid (1 g/L) over a period 4–24 h post treatment. Using transmission electron microscopy (TEM), early changes in Saprolegnia spores were detected. Mitochondrial degeneration was the most obvious sign observed following 4 h treatment in about 20% of randomly selected spores. We also investigated the effect of the treatment on nuclear division, mitochondrial activity and function using confocal laser scanning microscopy (CLSM). Fluorescence microscopy was also used to test the effect of treatment on mitochondrial membrane potential and formation of reactive oxygen species. Additionally, the viability and proliferation of treated spores that correlated to mitochondrial enzymatic activity were tested using an MTS assay. All obtained data pointed towards changes in the mitochondrial structure, membrane potential and enzymatic activity following treatment. We have found that boric acid has no effect on the integrity of membranes of Saprolegnia spores at concentrations tested. It is therefore likely that mitochondrial dysfunction is involved in the toxic activity of boric acid against Saprolegnia spp. PMID:25354209

  15. Effects of negative air ions on activity of neural substrates involved in autonomic regulation in rats

    NASA Astrophysics Data System (ADS)

    Suzuki, Satoko; Yanagita, Shinya; Amemiya, Seiichiro; Kato, Yumi; Kubota, Natsuko; Ryushi, Tomoo; Kita, Ichiro

    2008-07-01

    The neural mechanism by which negative air ions (NAI) mediate the regulation of autonomic nervous system activity is still unknown. We examined the effects of NAI on physiological responses, such as blood pressure (BP), heart rate (HR), and heart rate variability (HRV) as well as neuronal activity, in the paraventricular nucleus of the hypothalamus (PVN), locus coeruleus (LC), nucleus ambiguus (NA), and nucleus of the solitary tract (NTS) with c-Fos immunohistochemistry in anesthetized, spontaneously breathing rats. In addition, we performed cervical vagotomy to reveal the afferent pathway involved in mediating the effects of NAI on autonomic regulation. NAI significantly decreased BP and HR, and increased HF power of the HRV spectrum. Significant decreases in c-Fos positive nuclei in the PVN and LC, and enhancement of c-Fos expression in the NA and NTS were induced by NAI. After vagotomy, these physiological and neuronal responses to NAI were not observed. These findings suggest that NAI can modulate autonomic regulation through inhibition of neuronal activity in PVN and LC as well as activation of NA neurons, and that these effects of NAI might be mediated via the vagus nerves.

  16. Functional characterization of an antigen involved in an early step of T-cell activation.

    PubMed Central

    Cosulich, M E; Rubartelli, A; Risso, A; Cozzolino, F; Bargellesi, A

    1987-01-01

    An activation antigen, identified by the monoclonal antibody MLR3, is described that is present on activated T lymphocytes and thymocytes but not on resting T lymphocytes. Immunoprecipitation of radiolabeled membranes from an activated T-cell line showed that the MLR3-binding molecule has a molecular size of 28-34 kDa. Immunofluorescence analysis showed that the appearance of the MLR3 antigen is an early event and precedes that of the interleukin 2 receptor both in T lymphocytes and thymocytes. The proliferative response of resting T cells to OKT3-Sepharose and interleukin 1 or accessory cells, but not the interleukin 2-dependent proliferation, was inhibited by the addition of MLR3 monoclonal antibodies. Similar results wer also obtained in an interleukin 1-dependent human thymocyte proliferation assay. In addition when MLR3-positive cells were cultured with purified interleukin 1, MLR3 surface antigen expression was not observed. Thus MLR3 monoclonal antibody appears to recognize an antigen involved in an early step of T-cell activation related to interleukin 1-dependent functions and on both T lymphocytes and thymocytes. Images PMID:3295878

  17. Tryptase Clara, an activating protease for Sendai virus in rat lungs, is involved in pneumopathogenicity.

    PubMed Central

    Tashiro, M; Yokogoshi, Y; Tobita, K; Seto, J T; Rott, R; Kido, H

    1992-01-01

    Tryptase Clara is an arginine-specific serine protease localized exclusively in and secreted from Clara cells of the bronchial epithelium of rats (H. Kido, Y. Yokogoshi, K. Sakai, M. Tashiro, Y. Kishino, A. Fukutomi, and N. Katunuma, J. Biol. Chem. 267:13573-13579, 1992). The purified protease was shown in vitro to behave similarly to trypsin, cleaving the precursor glycoprotein F of Sendai virus at residue Arg-116 and activating viral infectivity in a dose-dependent manner. Anti-tryptase Clara antibody inhibited viral activation by the protease in vitro in lung block cultures and in vivo in infected rats. When the enzyme-specific antibody was administered intranasally to rats that were also infected intranasally with Sendai virus, activation of progeny virus in the lungs was significantly inhibited. Thus, multiple cycles of viral replication were suppressed, resulting in a reduction in lung lesions and in the mortality rate. These findings indicate that tryptase Clara is an activating protease for Sendai virus in rat lungs and is therefore involved in pulmonary pathogenicity of the virus in rats. Images PMID:1331518

  18. Study of Possible Mechanisms Involved in the Inhibitory Effects of Coumarin Derivatives on Neutrophil Activity

    PubMed Central

    Drábiková, Katarína; Pere?ko, Tomáš; Nosál', Radomír; Harmatha, Juraj; Šmidrkal, Jan; Jan?inová, Viera

    2013-01-01

    To specify the site of action of the synthetic coumarin derivatives 7-hydroxy-3-(4?-hydroxyphenyl) coumarin (HHC) and 7-hydroxy-3-(4?-hydroxyphenyl) dihydrocoumarin (HHDC), we evaluated their effects on extra- and intracellular reactive oxygen species (ROS) formation in phorbol-myristate-13-acetate (PMA) stimulated human neutrophils. We studied also the effects of HHC and HHDC on possible molecular mechanisms which participate in the activation of NADPH oxidase, that is, on PKC activity, on phosphorylation of some PKC isoforms (?, ?II, and ?), and on phosphorylation of the NADPH oxidase subunit p40phox. Without affecting cytotoxicity, both coumarines tested were effective inhibitors/scavengers of ROS produced by neutrophils on extracellular level. HHC markedly diminished oxidant production and also, intracellularly, decreased PKC activity and partly phosphorylation of PKC?, ?II. On the other hand, we did not observe any effect of coumarin derivatives on phosphorylation of PKC? and on phosphorylation of the NADPH oxidase subunit p40phox, which were suggested to be involved in the PMA-dependent intracellular activation process. In agreement with our previous findings, we assume that the different molecular structures of HHC and HHDC with their different physicochemical and free radical scavenging characteristics are responsible for their diverse effects on the parameters tested. PMID:24349608

  19. A? and NMDAR activation cause mitochondrial dysfunction involving ER calcium release.

    PubMed

    Ferreira, Ildete Luísa; Ferreiro, Elisabete; Schmidt, Jeannette; Cardoso, João M; Pereira, Cláudia M F; Carvalho, Ana Luísa; Oliveira, Catarina R; Rego, A Cristina

    2015-02-01

    Early cognitive deficits in Alzheimer's disease (AD) seem to be correlated to dysregulation of glutamate receptors evoked by amyloid-beta (A?) peptide. A? interference with the activity of N-methyl-d-aspartate receptors (NMDARs) may be a relevant factor for A?-induced mitochondrial toxicity and neuronal dysfunction. To evaluate the role of mitochondria in NMDARs activation mediated by A?, we followed in situ single-cell simultaneous measurement of cytosolic free Ca(2+)(Cai(2+)) and mitochondrial membrane potential in primary cortical neurons. Our results show that direct exposure to A? + NMDA largely increased Cai(2+) and induced immediate mitochondrial depolarization, compared with A? or NMDA alone. Mitochondrial depolarization induced by rotenone strongly inhibited the rise in Cai(2+) evoked by A? or NMDA, suggesting that mitochondria control Ca(2+) entry through NMDARs. However, incubation with rotenone did not preclude mitochondrial Ca(2+) (mitCa(2+)) retention in cells treated with A?. A?-induced Cai(2+) and mitCa(2+) rise were inhibited by ifenprodil, an antagonist of GluN2B-containing NMDARs. Exposure to A? + NMDA further evoked a higher mitCa(2+) retention, which was ameliorated in GluN2B(-/-) cortical neurons, largely implicating the involvement of this NMDAR subunit. Moreover, pharmacologic inhibition of endoplasmic reticulum (ER) inositol-1,4,5-triphosphate receptor (IP3R) and mitCa(2+) uniporter (MCU) evidenced that A? + NMDA-induced mitCa(2+) rise involves ER Ca(2+) release through IP3R and mitochondrial entry by the MCU. Altogether, data highlight mitCa(2+) dyshomeostasis and subsequent dysfunction as mechanisms relevant for early neuronal dysfunction in AD linked to A?-mediated GluN2B-composed NMDARs activation. PMID:25442114

  20. The Orosomucoid 1 protein is involved in the vitamin D – mediated macrophage de-activation process

    SciTech Connect

    Gemelli, Claudia, E-mail: claudia.gemelli@unimore.it [Department of Life Sciences, University of Modena and Reggio Emilia, Via Campi 287, 41125 Modena (Italy); Center for Regenerative Medicine, University of Modena and Reggio Emilia, Via Gottardi 100, 41125 Modena (Italy); Martello, Andrea; Montanari, Monica; Zanocco Marani, Tommaso; Salsi, Valentina; Zappavigna, Vincenzo; Parenti, Sandra; Vignudelli, Tatiana; Selmi, Tommaso; Ferrari, Sergio; Grande, Alexis [Department of Life Sciences, University of Modena and Reggio Emilia, Via Campi 287, 41125 Modena (Italy)

    2013-12-10

    Orosomucoid 1 (ORM1), also named Alpha 1 acid glycoprotein A (AGP-A), is an abundant plasma protein characterized by anti-inflammatory and immune-modulating properties. The present study was designed to identify a possible correlation between ORM1 and Vitamin D3 (1,25(OH)2D3), a hormone exerting a widespread effect on cell proliferation, differentiation and regulation of the immune system. In particular, the data described here indicated that ORM1 is a 1,25(OH)2D3 primary response gene, characterized by the presence of a VDRE element inside the 1 kb sequence of its proximal promoter region. This finding was demonstrated with gene expression studies, Chromatin Immunoprecipitation and luciferase transactivation experiments and confirmed by VDR full length and dominant negative over-expression. In addition, several experiments carried out in human normal monocytes demonstrated that the 1,25(OH)2D3 – VDR – ORM1 pathway plays a functional role inside the macrophage de-activation process and that ORM1 may be considered as a signaling molecule involved in the maintenance of tissue homeostasis and remodeling. - Highlights: • ORM1 is a Vitamin D primary response gene. • VD and its receptor VDR are involved in the de-activation process mediated by human resident macrophages. • The signaling pathway VD-VDR-ORM1 plays an important role in the control of macrophage de-activation process. • ORM1 may be defined as a signaling molecule implicated in the maintenance of tissue homeostasis and remodeling.

  1. Improving the active involvement of stakeholders and the public in flood risk management - tools of an involvement strategy and case study results from Austria, Germany and Italy

    NASA Astrophysics Data System (ADS)

    Fleischhauer, M.; Greiving, S.; Flex, F.; Scheibel, M.; Stickler, T.; Sereinig, N.; Koboltschnig, G.; Malvati, P.; Vitale, V.; Grifoni, P.; Firus, K.

    2012-09-01

    The EU Flood Risk Management Directive 2007/60/EC aims at an active involvement of interested parties in the setting up of flood risk management plans and thus calls for more governance-related decision-making. This requirement has two perspectives. On the one hand, there is (1) the question of how decision-makers can improve the quality of their governance process. On the other hand, there is (2) the question of how the public shall be appropriately informed and involved. These questions were the centre of the ERA-Net CRUE-funded project IMRA (integrative flood risk governance approach for improvement of risk awareness) that aimed at an optimisation of the flood risk management process by increasing procedural efficiency with an explicit involvement strategy. To reach this goal, the IMRA project partners developed two new approaches that were implemented in three case study areas for the first time in flood risk management: 1. risk governance assessment tool: An indicator-based benchmarking and monitoring tool was used to evaluate the performance of a flood risk management system in regard to ideal risk governance principles; 2. social milieu approach: The concept of social milieus was used to gain a picture of the people living in the case study regions to learn more about their lifestyles, attitudes and values and to use this knowledge to plan custom-made information and participation activities for the broad public. This paper presents basic elements and the application of two innovative approaches as a part of an "involvement strategy" that aims at the active involvement of all interested parties (stakeholders) for assessing, reviewing and updating flood risk management plans, as formulated in the EU Flood Risk Management Directive 2007/60/EC.

  2. atRA-induced apoptosis of mouse embryonic palate mesenchymal cells involves activation of MAPK pathway

    SciTech Connect

    Yu Zengli [Department of Nutrition and Food Hygiene, School of Public Health, Zhengzhou University, No. 40 Daxue Road, Zhengzhou 450052 (China)]. E-mail: yuzengli@263.net; Xing Ying [Stem Cell Research Center, Zhengzhou University, 40 Daxue Road, Zhengzhou 450052 (China)]. E-mail: xingy@zzu.edu.cn

    2006-08-15

    Our previous studies have shown that atRA treatment resulted in cell-cycle block and growth inhibition in mouse embryonic palatal mesenchymal (MEPM). In the current study, gestation day (GD) 13 MEPM cells were used to test the hypothesis that the growth inhibition by atRA is due to apoptosis. The effects of atRA on apoptosis were assessed by performing MTT assay, Cell Death Detection ELISA and flow cytometry, respectively. Data analysis confirmed that atRA treatment induced apoptosis-like cell death, as shown by decreased cell viability and increased fragmented DNA and sub-G1 fraction. atRA-induced apoptosis was associated with upregulation of bcl-2, translocation of bax protein to the mitochondria from the cytosol, activation of caspase-3 and cytochrome c release into cytosol. atRA-induced apoptosis was abrogated by z-DEVD-fmk, a caspase-3 specific inhibitor, and z-VAD-fmk, a general caspase inhibitor, suggesting that the atRA-induced cell death of MEPM cells occurs through the cytochrome c- and caspase-3-dependent pathways. In addition, atRA treatment caused a strong and sustained activation of c-Jun N-terminal kinase (JNK) and p38 kinase (p38), as well as an early but transient activation of extracellular signal-regulated kinase (ERK). Importantly, atRA-induced DNA fragmentation and capase-3 activation were prevented by pretreatment with the JNK inhibitor (SP600125) and the p38 MAPK inhibitor (SB202190), but not by pretreatment with MEK inhibitor (U0126). From these results, we suggest that mitogen-activated protein kinase-dependent pathways is involved in the atRA-induced apoptosis of MEPM cells.

  3. Activation of phospholipase A2 is involved in indomethacin-induced damage in Caco-2 cells.

    PubMed

    Sivalingam, Nageswaran; Basivireddy, Jayasree; Pulimood, Anna B; Balasubramanian, K A; Jacob, Molly

    2009-08-01

    Nonsteroidal anti-inflammatory drugs (NSAIDs), widely used in clinical practice, cause adverse effects in the gastrointestinal tract. These effects have been attributed to mechanisms such as drug-induced cyclooxygenase inhibition, oxidative stress, mitochondrial dysfunction and changes in cell membrane lipids. Our previous study showed that indomethacin (an NSAID commonly used in toxicity studies) caused activation of cytosolic phospholipase A(2) (cPLA(2)) in the rat small intestine. We hypothesized that activation of cPLA(2) is an important event in the pathogenesis of indomethacin-induced damage in enterocytes. To test this, we incubated enterocyte-like Caco-2 cells with indomethacin, with and without pretreatment with methyl arachidonyl fluorophosphonate (MAFP), an inhibitor of cPLA(2). Cells treated with indomethacin showed decreased viability and evidence of oxidative stress and morphological cell damage. Phospholipids were degraded in these cells, with increases in the levels of lysophospholipids and arachidonic acid. There was no evidence of apoptosis in the cells in response to the drug. Pretreatment of the cells with MAFP attenuated the drug-induced effects seen. This shows that activation of phospholipase A(2) appears to be an important event in the pathogenesis of indomethacin-induced damage in Caco-2 cells. To our knowledge, this is the first report that implicates the involvement of this enzyme in NSAID-induced enteropathy. PMID:19470405

  4. Transmembrane myosin chitin synthase involved in mollusc shell formation produced in Dictyostelium is active

    SciTech Connect

    Schoenitzer, Veronika [INM - Leibniz Institute for New Materials, Biomineralisation Group, Campus D2.2, D-66123 Saarbruecken (Germany) [INM - Leibniz Institute for New Materials, Biomineralisation Group, Campus D2.2, D-66123 Saarbruecken (Germany); Universitaet Regensburg, Biochemie I, Universitaetsstrasse 31, D-93053 Regensburg (Germany); Eichner, Norbert [Universitaet Regensburg, Biochemie I, Universitaetsstrasse 31, D-93053 Regensburg (Germany)] [Universitaet Regensburg, Biochemie I, Universitaetsstrasse 31, D-93053 Regensburg (Germany); Clausen-Schaumann, Hauke [Munich University of Applied Sciences, Lothstrasse 34, D-80335 Muenchen, Germany, and Center for NanoScience (CeNS), Geschwister-Scholl-Platz 1, D-80539 Muenchen (Germany)] [Munich University of Applied Sciences, Lothstrasse 34, D-80335 Muenchen, Germany, and Center for NanoScience (CeNS), Geschwister-Scholl-Platz 1, D-80539 Muenchen (Germany); Weiss, Ingrid M., E-mail: ingrid.weiss@inm-gmbh.de [INM - Leibniz Institute for New Materials, Biomineralisation Group, Campus D2.2, D-66123 Saarbruecken (Germany); Universitaet Regensburg, Biochemie I, Universitaetsstrasse 31, D-93053 Regensburg (Germany)

    2011-12-02

    Highlights: Black-Right-Pointing-Pointer Dictyostelium produces the 264 kDa myosin chitin synthase of bivalve mollusc Atrina. Black-Right-Pointing-Pointer Chitin synthase activity releases chitin, partly associated with the cell surface. Black-Right-Pointing-Pointer Membrane extracts of transgenic slime molds produce radiolabeled chitin in vitro. Black-Right-Pointing-Pointer Chitin producing Dictyostelium cells can be characterized by atomic force microscopy. Black-Right-Pointing-Pointer This model system enables us to study initial processes of chitin biomineralization. -- Abstract: Several mollusc shells contain chitin, which is formed by a transmembrane myosin motor enzyme. This protein could be involved in sensing mechanical and structural changes of the forming, mineralizing extracellular matrix. Here we report the heterologous expression of the transmembrane myosin chitin synthase Ar-CS1 of the bivalve mollusc Atrina rigida (2286 amino acid residues, M.W. 264 kDa/monomer) in Dictyostelium discoideum, a model organism for myosin motor proteins. Confocal laser scanning immunofluorescence microscopy (CLSM), chitin binding GFP detection of chitin on cells and released to the cell culture medium, and a radiochemical activity assay of membrane extracts revealed expression and enzymatic activity of the mollusc chitin synthase in transgenic slime mold cells. First high-resolution atomic force microscopy (AFM) images of Ar-CS1 transformed cellulose synthase deficient D. discoideumdcsA{sup -} cell lines are shown.

  5. 1-Methyl-4-phenylpyridinium induces synaptic dysfunction through a pathway involving caspase and PKCdelta enzymatic activities.

    PubMed

    Serulle, Yafell; Morfini, Gerardo; Pigino, Gustavo; Moreira, Jorge E; Sugimori, Mutsuyuki; Brady, Scott T; Llinás, Rodolfo R

    2007-02-13

    1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine administration has been used, in various mammalian species, as an experimental model of Parkinson's disease. The pathogenesis for such pharmacologically induced Parkinson's disease involves 1-methyl-4-phenylpyridinium (MPP+), the active metabolite of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine. This metabolite produces rapid degeneration of nigrostriatal dopaminergic neurons, which causes the parkinsonian syndrome. In this work, we show that injection of MPP+ into the presynaptic terminal of the squid giant synapse blocks synaptic transmission without affecting the presynaptic action potential or the presynaptic calcium currents. These effects of MPP+ were mimicked by the injection of an active form of caspase-3 and prevented by inhibitors of caspase-3 and protein kinase C delta. Ultrastructurally, MPP+-injected synapses showed a dramatic reduction in the number of neurotransmitter vesicles at the presynaptic active zone, as compared with control synapses. Otherwise, normal docking and clathrin-coated vesicles were observed, albeit at much reduced numbers. These results indicate that MPP+ acutely reduces presynaptic vesicular availability, not release, and that MPP+-induced pathogenesis results from presynaptic dysfunction that leads, secondarily, to dying-back neuropathy in affected neurons. PMID:17287339

  6. Activation of PPAR{gamma} is not involved in butyrate-induced epithelial cell differentiation

    SciTech Connect

    Ulrich, S. [1st Department of Medicine-ZAFES, Johann Wolfgang Goethe University, Theodor-Stern-Kai 7, 60590 Frankfurt (Germany); Waechtershaeuser, A. [1st Department of Medicine-ZAFES, Johann Wolfgang Goethe University, Theodor-Stern-Kai 7, 60590 Frankfurt (Germany); Loitsch, S. [1st Department of Medicine-ZAFES, Johann Wolfgang Goethe University, Theodor-Stern-Kai 7, 60590 Frankfurt (Germany); Knethen, A. von [1st Department of Biochemistry-ZAFES, Johann Wolfgang Goethe University, Theodor-Stern-Kai 7, 60590 Frankfurt (Germany); Bruene, B. [1st Department of Biochemistry-ZAFES, Johann Wolfgang Goethe University, Theodor-Stern-Kai 7, 60590 Frankfurt (Germany); Stein, J. [1st Department of Medicine-ZAFES, Johann Wolfgang Goethe University, Theodor-Stern-Kai 7, 60590 Frankfurt (Germany)]. E-mail: j.stein@em.uni-frankfurt.de

    2005-10-15

    Histone deacetylase-inhibitors affect growth and differentiation of intestinal epithelial cells by inducing expression of several transcription factors, e.g. Peroxisome proliferator-activated receptor {gamma} (PPAR{gamma}) or vitamin D receptor (VDR). While activation of VDR by butyrate mainly seems to be responsible for cellular differentiation, the activation of PPAR{gamma} in intestinal cells remains to be elucidated. The aim of this study was to determine the role of PPAR{gamma} in butyrate-induced cell growth inhibition and differentiation induction in Caco-2 cells. Treatment with PPAR{gamma} ligands ciglitazone and BADGE (bisphenol A diglycidyl) enhanced butyrate-induced cell growth inhibition in a dose- and time-dependent manner, whereas cell differentiation was unaffected after treatment with PPAR{gamma} ligands rosiglitazone and MCC-555. Experiments were further performed in dominant-negative PPAR{gamma} mutant cells leading to an increase in cell growth whereas butyrate-induced cell differentiation was again unaffected. The present study clearly demonstrated that PPAR{gamma} is involved in butyrate-induced inhibition of cell growth, but seems not to play an essential role in butyrate-induced cell differentiation.

  7. Carbohydrate-Active Enzymes Involved in the Secondary Cell Wall Biogenesis in Hybrid Aspen1

    PubMed Central

    Aspeborg, Henrik; Schrader, Jarmo; Coutinho, Pedro M.; Stam, Mark; Kallas, Åsa; Djerbi, Soraya; Nilsson, Peter; Denman, Stuart; Amini, Bahram; Sterky, Fredrik; Master, Emma; Sandberg, Göran; Mellerowicz, Ewa; Sundberg, Björn; Henrissat, Bernard; Teeri, Tuula T.

    2005-01-01

    Wood formation is a fundamental biological process with significant economic interest. While lignin biosynthesis is currently relatively well understood, the pathways leading to the synthesis of the key structural carbohydrates in wood fibers remain obscure. We have used a functional genomics approach to identify enzymes involved in carbohydrate biosynthesis and remodeling during xylem development in the hybrid aspen Populus tremula × tremuloides. Microarrays containing cDNA clones from different tissue-specific libraries were hybridized with probes obtained from narrow tissue sections prepared by cryosectioning of the developing xylem. Bioinformatic analyses using the sensitive tools developed for carbohydrate-active enzymes allowed the identification of 25 xylem-specific glycosyltransferases belonging to the Carbohydrate-Active EnZYme families GT2, GT8, GT14, GT31, GT43, GT47, and GT61 and nine glycosidases (or transglycosidases) belonging to the Carbohydrate-Active EnZYme families GH9, GH10, GH16, GH17, GH19, GH28, GH35, and GH51. While no genes encoding either polysaccharide lyases or carbohydrate esterases were found among the secondary wall-specific genes, one putative O-acetyltransferase was identified. These wood-specific enzyme genes constitute a valuable resource for future development of engineered fibers with improved performance in different applications. PMID:15734915

  8. Occupational Styrene Exposure Induces Stress-Responsive Genes Involved in Cytoprotective and Cytotoxic Activities

    PubMed Central

    Strafella, Elisabetta; Bracci, Massimo; Staffolani, Sara; Manzella, Nicola; Giantomasi, Daniele; Valentino, Matteo; Amati, Monica; Tomasetti, Marco; Santarelli, Lory

    2013-01-01

    Objective The aim of this study was to evaluate the expression of a panel of genes involved in toxicology in response to styrene exposure at levels below the occupational standard setting. Methods Workers in a fiber glass boat industry were evaluated for a panel of stress- and toxicity-related genes and associated with biochemical parameters related to hepatic injury. Urinary styrene metabolites (MA+PGA) of subjects and environmental sampling data collected for air at workplace were used to estimate styrene exposure. Results Expression array analysis revealed massive upregulation of genes encoding stress-responsive proteins (HSPA1L, EGR1, IL-6, IL-1?, TNSF10 and TNF?) in the styrene-exposed group; the levels of cytokines released were further confirmed in serum. The exposed workers were then stratified by styrene exposure levels. EGR1 gene upregulation paralleled the expression and transcriptional protein levels of IL-6, TNSF10 and TNF? in styrene exposed workers, even at low level. The activation of the EGR1 pathway observed at low-styrene exposure was associated with a slight increase of hepatic markers found in highly exposed subjects, even though they were within normal range. The ALT and AST levels were not affected by alcohol consumption, and positively correlated with urinary styrene metabolites as evaluated by multiple regression analysis. Conclusion The pro-inflammatory cytokines IL-6 and TNF? are the primary mediators of processes involved in the hepatic injury response and regeneration. Here, we show that styrene induced stress responsive genes involved in cytoprotection and cytotoxicity at low-exposure, that proceed to a mild subclinical hepatic toxicity at high-styrene exposure. PMID:24086524

  9. Molecular Mechanisms Involved in the Antitumor Activity of Cannabinoids on Gliomas: Role for Oxidative Stress

    PubMed Central

    Massi, Paola; Valenti, Marta; Solinas, Marta; Parolaro, Daniela

    2010-01-01

    Cannabinoids, the active components of Cannabis sativa, have been shown to exert antiproliferative and proapoptotic effects on a wide spectrum of tumor cells and tissues. Of interest, cannabinoids have displayed great potency in reducing the growth of glioma tumors, one of the most aggressive CNS tumors, either in vitro or in animal experimental models curbing the growth of xenografts generated by subcutaneous or intrathecal injection of glioma cells in immune-deficient mice. Cannabinoids appear to be selective antitumoral agents as they kill glioma cells without affecting the viability of non-transformed cells. This review will summarize the anti-cancer properties that cannabinoids exert on gliomas and discuss their potential action mechanisms that appear complex, involving modulation of multiple key cell signaling pathways and induction of oxidative stress in glioma cells. PMID:24281104

  10. Lipotoxicity Mediated Cell Dysfunction and Death Involves Lysosomal Membrane Permeabilization and Cathepsin L Activity

    PubMed Central

    Almaguel, Frankis G.; Liu, Jo-Wen; Pacheco, Fabio J.; De Leon, Daisy; Casiano, Carlos A.; De Leon, Marino

    2010-01-01

    Lipotoxicity, which is triggered when cells are exposed to elevated levels of free fatty acids, involves cell dysfunction and apoptosis and is emerging as an underlying factor contributing to various pathological conditions including disorders of the central nervous system and diabetes. We have shown that palmitic acid (PA)-induced lipotoxicity (PA-LTx) in nerve growth factor-differentiated PC12 (NGFDPC12) cells is linked to an augmented state of cellular oxidative stress (ASCOS) and apoptosis, and that these events are inhibited by docosahexanoic acid (DHA). The mechanisms of PA-LTx in nerve cells are not well understood, but our previous findings indicate that it involves ROS generation, mitochondrial membrane permeabilization (MMP), and caspase activation. The present study used nerve growth factor differentiated PC12 cells (NGFDPC12 cells) and found that lysosomal membrane permeabilization (LMP) is an early event during PA-induced lipotoxicity that precedes MMP and apoptosis. Cathepsin L, but not cathepsin B, is an important contributor in this process since its pharmacological inhibition significantly attenuated LMP, MMP, and apoptosis. In addition, co-treatment of NGFDPC12 cells undergoing lipotoxicity with DHA significantly reduced LMP, suggesting that DHA acts by antagonizing upstream signals leading to lysosomal dysfunction. These results suggest that LMP is a key early mediator of lipotoxicity, and underscore the value of interventions targeting upstream signals leading to LMP for the treatment of pathological conditions associated with lipotoxicity. PMID:20043885

  11. A novel carotenoid cleavage activity involved in the biosynthesis of Citrus fruit-specific apocarotenoid pigments

    PubMed Central

    Rodrigo, María J.; Alquézar, Berta; Al-Babili, Salim

    2013-01-01

    Citrus is the first tree crop in terms of fruit production. The colour of Citrus fruit is one of the main quality attributes, caused by the accumulation of carotenoids and their derivative C30 apocarotenoids, mainly ?-citraurin (3-hydroxy-?-apo-8?-carotenal), which provide an attractive orange-reddish tint to the peel of oranges and mandarins. Though carotenoid biosynthesis and its regulation have been extensively studied in Citrus fruits, little is known about the formation of C30 apocarotenoids. The aim of this study was to the identify carotenoid cleavage enzyme(s) [CCD(s)] involved in the peel-specific C30 apocarotenoids. In silico data mining revealed a new family of five CCD4-type genes in Citrus. One gene of this family, CCD4b1, was expressed in reproductive and vegetative tissues of different Citrus species in a pattern correlating with the accumulation of C30 apocarotenoids. Moreover, developmental processes and treatments which alter Citrus fruit peel pigmentation led to changes of ?-citraurin content and CCD4b1 transcript levels. These results point to the involvement of CCD4b1 in ?-citraurin formation and indicate that the accumulation of this compound is determined by the availability of the presumed precursors zeaxanthin and ?-cryptoxanthin. Functional analysis of CCD4b1 by in vitro assays unequivocally demonstrated the asymmetric cleavage activity at the 7?,8? double bond in zeaxanthin and ?-cryptoxanthin, confirming its role in C30 apocarotenoid biosynthesis. Thus, a novel plant carotenoid cleavage activity targeting the 7?,8? double bond of cyclic C40 carotenoids has been identified. These results suggest that the presented enzyme is responsible for the biosynthesis of C30 apocarotenoids in Citrus which are key pigments in fruit coloration. PMID:24006419

  12. Dark-induced senescence of barley leaves involves activation of plastid transglutaminases.

    PubMed

    Sobieszczuk-Nowicka, E; Zmienko, A; Samelak-Czajka, A; ?uczak, M; Pietrowska-Borek, M; Iorio, R; Del Duca, S; Figlerowicz, M; Legocka, J

    2015-04-01

    Transglutaminases (E.C. 2.3.2.13) catalyze the post-translational modification of proteins by establishing ?-(?-glutamyl) lysine isopeptide bonds and by the covalent conjugation of polyamines to endo-glutamyl residues of proteins. In light of the confirmed role of transglutaminases in animal cell apoptosis and only limited information on the role of these enzymes in plant senescence, we decided to investigate the activity of chloroplast transglutaminases (ChlTGases) and the fate of chloroplast-associated polyamines in Hordeum vulgare L. 'Nagrad' leaves, where the senescence process was induced by darkness (day 0) and continued until chloroplast degradation (day 12). Using an anti-TGase antibody, we detected on a subcellular level, the ChlTGases that were associated with destacked/degraded thylakoid membranes, and beginning on day 5, were also found in the stroma. Colorimetric and radiometric assays revealed during senescence an increase in ChlTGases enzymatic activity. The MS/MS identification of plastid proteins conjugated with exogenous polyamines had shown that the ChlTGases are engaged in the post-translational modification of proteins involved in photosystem organization, stress response, and oxidation processes. We also computationally identified the cDNA of Hv-Png1-like, a barley homologue of the Arabidopsis AtPng1 gene. Its mRNA level was raised from days 3 to 10, indicating that transcriptional regulation controls the activity of barley ChlTGases. Together, the presented results deepen our knowledge of the mechanisms of the events happened in dark-induced senescence of barley leaves that might be activation of plastid transglutaminases. PMID:25583605

  13. Involvement of ER stress and activation of apoptotic pathways in fisetin induced cytotoxicity in human melanoma.

    PubMed

    Syed, Deeba N; Lall, Rahul K; Chamcheu, Jean Christopher; Haidar, Omar; Mukhtar, Hasan

    2014-12-01

    The prognosis of malignant melanoma remains poor in spite of recent advances in therapeutic strategies for the deadly disease. Fisetin, a dietary flavonoid is currently being investigated for its growth inhibitory properties in various cancer models. We previously showed that fisetin inhibited melanoma growth in vitro and in vivo. Here, we evaluated the molecular basis of fisetin induced cytotoxicity in metastatic human melanoma cells. Fisetin treatment induced endoplasmic reticulum (ER) stress in highly aggressive A375 and 451Lu human melanoma cells, as revealed by up-regulation of ER stress markers including IRE1?, XBP1s, ATF4 and GRP78. Time course analysis indicated that the ER stress was associated with activation of the extrinsic and intrinsic apoptotic pathways. Fisetin treated 2-D melanoma cultures displayed autophagic response concomitant with induction of apoptosis. Prolonged treatment (16days) with fisetin in a 3-D reconstituted melanoma model resulted in inhibition of melanoma progression with significant apoptosis, as evidenced by increased staining of cleaved Caspase-3 in the treated constructs. However, no difference in the expression of autophagic marker LC-3 was noted between treated and control groups. Fisetin treatment to 2-D melanoma cultures resulted in phosphorylation and activation of the multifunctional AMP-activated protein kinase (AMPK) involved in the regulation of diverse cellular processes, including autophagy and apoptosis. Silencing of AMPK failed to prevent cell death indicating that fisetin induced cytotoxicity is mediated through both AMPK-dependent and -independent mechanisms. Taken together, our studies confirm apoptosis as the primary mechanism through which fisetin inhibits melanoma cell growth and that activation of both extrinsic and intrinsic pathways contributes to fisetin induced cytotoxicity. PMID:25016296

  14. Autophagy activation by interferon-? via the p38 mitogen-activated protein kinase signalling pathway is involved in macrophage bactericidal activity

    PubMed Central

    Matsuzawa, Takeshi; Fujiwara, Eri; Washi, Yui

    2014-01-01

    Macrophages are involved in many essential immune functions. Their role in cell-autonomous innate immunity is reinforced by interferon-? (IFN-?), which is mainly secreted by proliferating type 1 T helper cells and natural killer cells. Previously, we showed that IFN-? activates autophagy via p38 mitogen-activated protein kinase (p38 MAPK), but the biological importance of this signalling pathway has not been clear. Here, we found that macrophage bactericidal activity increased by 4 hr after IFN-? stimulation. Inducible nitric oxide synthase (NOS2) is a major downstream effector of the Janus kinase–signal transducer and activator of transcription 1 signalling pathway that contributes to macrophage bactericidal activity via nitric oxide (NO) generation. However, no NO generation was observed after 4 hr of IFN-? stimulation, and macrophage bactericidal activity at early stages after IFN-? stimulation was not affected by the NOS inhibitors, NG-methyl-l-arginine acetate salt and diphenyleneiodonium chloride. These results suggest that an NOS2-independent signalling pathway is involved in IFN-?-mediated bactericidal activity. We also found that this macrophage activity was attenuated by the addition of the p38 MAPK inhibitors, PD 169316, SB 202190, and SB 203580, or by the expression of short hairpin RNA against p38? or the essential factors for autophagy, Atg5 and Atg7. Collectively, our results suggest that the IFN-?-mediated autophagy via p38 MAPK, without the involvement of NOS2, also contributes to the ability of macrophages to kill intracellular bacteria. These observations provide direct evidence that p38 MAPK-mediated autophagy can support IFN-?-mediated cell-autonomous innate immunity. PMID:24032631

  15. 77 FR 3010 - In the Matter of Mr. Francis Guilbeau; Order Prohibiting Involvement in NRC-Licensed Activities

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-20

    ...inspection was conducted in response to an event that occurred on March 15, 2010, involving the loss of a sealed source of iridium-192 while performing licensed activities in offshore Federal waters. On June 28, 2010, the NRC's Office of...

  16. 78 FR 66970 - In the Matter of Michael J. Buhrman; Order Prohibiting Involvement in NRC-Licensed Activities...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-07

    ...IA-13-025] In the Matter of Michael J. Buhrman; Order Prohibiting Involvement...Activities (Effective Immediately) I. Michael J. Buhrman was formerly employed as a senior...effective immediately, that: 1. Michael J. Buhrman is prohibited from engaging...

  17. Mothers' and Fathers' Involvement in Home Activities with Their Children: Psychosocial Factors and the Role of Parental Self-Efficacy

    ERIC Educational Resources Information Center

    Giallo, Rebecca; Treyvaud, Karli; Cooklin, Amanda; Wade, Catherine

    2013-01-01

    Parent involvement in play, learning, and everyday home activities is important for promoting children's cognitive and language development. The aims of the study were to (a) examine differences between mothers' and fathers' self-reported involvement with their children, (b) explore the relationship between child, parent and family factors, and…

  18. Parent Involvement Activities in School Improvement Plans in the Northwest Region. Summary. Issues & Answers. REL 2008-No. 064

    ERIC Educational Resources Information Center

    Speth, Timothy; Saifer, Steffen; Forehand, Gregory

    2008-01-01

    This document presents a summary of the larger report, "Parent Involvement Activities in School Improvement Plans in the Northwest Region." Although the No Child Left Behind Act of 2001 (NCLB) spells out parent involvement requirements for schools in need of improvement, the majority of the Northwest Region school improvement plans reviewed failed…

  19. Involvement of both PKS and NRPS in antibacterial activity in Lysobacter enzymogenes OH11.

    PubMed

    Zhang, Juan; Du, Liangcheng; Liu, Fengquan; Xu, Feifei; Hu, Baishi; Venturi, Vittorio; Qian, Guoliang

    2014-06-01

    Polyketides and nonribosomal peptides represent two large families of natural products (NPs) with diverse structures and important functions. They are synthesized by polyketide synthase (PKS) and nonribosomal peptide synthetase (NRPS), respectively. Lysobacter enzymogenes is emerging as a novel biocontrol agent against pathogens of crop plants and a new source of bioactive NPs, such as antibacterial antibiotic WAP-8294A2 and antifungal antibiotic HSAF. Genome survey of strain OH11, a Chinese L. enzymogenes isolate, detected four novel PKS, NRPS or hybrid gene clusters, designed as cluster A to D. We further individually mutated five genes (PKS or NRPS) located in these four gene clusters and showed that a PKS gene in cluster A and an NRPS gene in cluster D were involved in the antibacterial activity via a WAP-8294A2 dependent way. The data also showed that none of the five genes was associated with antifungal activity and the regulation of HSAF biosynthesis. Our results reveal the unusual regulatory role of these PKS and NRPS genes that were discovered from genome mining in L. enzymogenes. PMID:24801439

  20. Plasminogen Activator Inhibitor-1 Is Involved in Streptozotocin-Induced Bone Loss in Female Mice

    PubMed Central

    Tamura, Yukinori; Kawao, Naoyuki; Okada, Kiyotaka; Yano, Masato; Okumoto, Katsumi; Matsuo, Osamu; Kaji, Hiroshi

    2013-01-01

    In diabetic patients, the risk of fracture is high because of impaired bone formation. However, the details of the mechanisms in the development of diabetic osteoporosis remain unclear. In the current study, we investigated the role of plasminogen activator inhibitor (PAI)-1 in the pathogenesis of type 1 diabetic osteoporosis by using PAI-1–deficient mice. Quantitative computed tomography analysis showed that PAI-1 deficiency protected against streptozotocin-induced bone loss in female mice but not in male mice. PAI-1 deficiency blunted the changes in the levels of Runx2, osterix, and alkaline phosphatase in tibia as well as serum osteocalcin levels suppressed by the diabetic state in female mice only. Furthermore, the osteoclast levels in tibia, suppressed in diabetes, were also blunted by PAI-1 deficiency in female mice. Streptozotocin markedly elevated the levels of PAI-1 mRNA in liver in female mice only. In vitro study demonstrated that treatment with active PAI-1 suppressed the levels of osteogenic genes and mineralization in primary osteoblasts from female mouse calvaria. In conclusion, the current study indicates that PAI-1 is involved in the pathogenesis of type 1 diabetic osteoporosis in females. The expression of PAI-1 in the liver and the sensitivity of bone cells to PAI-1 may be an underlying mechanism. PMID:23715621

  1. Identification of furin pro-region determinants involved in folding and activation.

    PubMed Central

    Bissonnette, Lyne; Charest, Gabriel; Longpré, Jean-Michel; Lavigne, Pierre; Leduc, Richard

    2004-01-01

    The pro-region of the subtilisin-like convertase furin acts early in the biosynthetic pathway as an intramolecular chaperone to enable proper folding of the zymogen, and later on as an inhibitor to constrain the activity of the enzyme until it reaches the trans -Golgi network. To identify residues that are important for pro-region function, we initially identified amino acids that are conserved among the pro-regions of various mammalian convertases. Site-directed mutagenesis of 17 selected amino acids within the 89-residue pro-region and biosynthetic labelling revealed that I60A-furin and H66A-furin were rapidly degraded in a proteasome-dependent manner, while W34A-furin and F67A-furin did not show any autocatalytic activation. Intriguingly, the latter mutants proteolytically cleaved pro-von Willebrand factor precursor to the mature polypeptide, suggesting that the mutations permitted proper folding, but did not allow the pro-region to exercise its role in inhibiting the enzyme. Homology modelling of furin's pro-region revealed that residues Ile-60 and His-66 might be crucial in forming the binding interface with the catalytic domain, while residues Trp-34 and Phe-67 might be involved in maintaining a hydrophobic core within the pro-region itself. These results provide structural insights into the dual role of furin's pro-region. PMID:14741044

  2. Mechanisms involved in Escherichia coli and Serratia marcescens removal during activated sludge wastewater treatment.

    PubMed

    Orruño, Maite; Garaizabal, Idoia; Bravo, Zaloa; Parada, Claudia; Barcina, Isabel; Arana, Inés

    2014-10-01

    Wastewater treatment reduces environmental contamination by removing gross solids and mitigating the effects of pollution. Treatment also reduces the number of indicator organisms and pathogens. In this work, the fates of two coliform bacteria, Escherichia coli and Serratia marcescens, were analyzed in an activated sludge process to determine the main mechanisms involved in the reduction of pathogenic microorganisms during wastewater treatment. These bacteria, modified to express green fluorescent protein, were inoculated in an activated sludge unit and in batch systems containing wastewater. The results suggested that, among the different biological factors implied in bacterial removal, bacterivorous protozoa play a key role. Moreover, a representative number of bacteria persisted in the system as free-living or embedded cells, but their distribution into liquid or solid fractions varied depending on the bacterium tested, questioning the real value of bacterial indicators for the control of wastewater treatment process. Additionally, viable but nonculturable cells constituted an important part of the bacterial population adhered to solid fractions, what can be derived from the competition relationships with native bacteria, present in high densities in this environment. These facts, taken together, emphasize the need for reliable quantitative and qualitative analysis tools for the evaluation of pathogenic microbial composition in sludge, which could represent an undefined risk to public health and ecosystem functions when considering its recycling. PMID:25044599

  3. Are serotonergic neurons involved in the control of anxiety and in the anxiolytic activity of benzodiazepines?

    PubMed

    Thiebot, M H

    1986-05-01

    Several studies have shown that, like benzodiazepines (BZP), treatments able to reduce or block the activity of CNS serotonergic (5-HT) neurons released punished behavior. Therefore, 5-HT mechanisms have been tentatively implicated in the anti-punishment (anxiolytic?) activity of BZP. Numerous data, however, are not in keeping with this hypothesis. Since not responding enables the animals to avoid punishment but also delays the receipt of food-reward, one of these factors could be an alteration of waiting capacities. Indeed, we have shown that diazepam released behavioral suppression in conflict schedules only when the duration of the punished periods exceeded 1 minute. Moreover, in rats allowed to choose in a T-maze between immediate-but-small vs. delayed-but-large reward, BZP significantly decreased the frequency with which the delayed reward was chosen, with 5-HT uptake blockers producing opposite effects. Therefore, one can hypothesize that BZP render the animals less prone than controls to tolerate delay of reward and that 5-HT mechanisms may be involved in this phenomenon. An altered tolerance to delay of reward should be taken into account when interpreting the BZP-induced release of behavioral inhibition in classical conflict procedures. PMID:2873593

  4. Mechanisms involved in Escherichia coli and Serratia marcescens removal during activated sludge wastewater treatment

    PubMed Central

    Orruño, Maite; Garaizabal, Idoia; Bravo, Zaloa; Parada, Claudia; Barcina, Isabel; Arana, Inés

    2014-01-01

    Wastewater treatment reduces environmental contamination by removing gross solids and mitigating the effects of pollution. Treatment also reduces the number of indicator organisms and pathogens. In this work, the fates of two coliform bacteria, Escherichia coli and Serratia marcescens, were analyzed in an activated sludge process to determine the main mechanisms involved in the reduction of pathogenic microorganisms during wastewater treatment. These bacteria, modified to express green fluorescent protein, were inoculated in an activated sludge unit and in batch systems containing wastewater. The results suggested that, among the different biological factors implied in bacterial removal, bacterivorous protozoa play a key role. Moreover, a representative number of bacteria persisted in the system as free-living or embedded cells, but their distribution into liquid or solid fractions varied depending on the bacterium tested, questioning the real value of bacterial indicators for the control of wastewater treatment process. Additionally, viable but nonculturable cells constituted an important part of the bacterial population adhered to solid fractions, what can be derived from the competition relationships with native bacteria, present in high densities in this environment. These facts, taken together, emphasize the need for reliable quantitative and qualitative analysis tools for the evaluation of pathogenic microbial composition in sludge, which could represent an undefined risk to public health and ecosystem functions when considering its recycling. PMID:25044599

  5. Glycogen synthase kinase-3? activation mediates rotenone-induced cytotoxicity with the involvement of microtubule destabilization.

    PubMed

    Hongo, Haruyuki; Kihara, Takeshi; Kume, Toshiaki; Izumi, Yasuhiko; Niidome, Tetsuhiro; Sugimoto, Hachiro; Akaike, Akinori

    2012-09-14

    Rotenone, a mitochondrial complex I inhibitor, has been used to generate animal and cell culture models of Parkinson's disease. Recent studies suggest that microtubule destabilization causes selective dopaminergic neuronal loss. In this study, we investigated glycogen synthase kinase-3? (GSK3?) involvement in rotenone-induced microtubule destabilization. Rotenone-induced cytotoxicity in SH-SY5Y cells was attenuated by the GSK3? inhibitor SB216763. Tau, a microtubule-associated protein and substrate for GSK3?, has been implicated in the pathogenesis of tauopathies such as Alzheimer's disease. Rotenone induced an increase in phosphorylated tau, the effect of which was attenuated by concomitant treatment with SB216763. Rotenone treatment also decreased tau expression in the microtubule fraction and increased tau expression in the cytosol fraction. These effects were suppressed by SB216763, which suggests that rotenone reduces the capacity of tau to bind microtubules. Rotenone treatment increased the amount of free tubulin and reduced the amount of polymerized tubulin, indicating that rotenone destabilizes microtubules. Rotenone-induced microtubule destabilization was suppressed by SB216763 and taxol, a microtubule stabilizer. Taxol prevented rotenone-induced cytotoxicity and morphological changes. Taken together, these results suggest that rotenone-induced cytotoxicity is mediated by microtubule destabilization via GSK3? activation, and that microtubule destabilization is caused by reduction in the binding capacity of tau to microtubules, which is a result of tau phosphorylation via GSK3? activation. PMID:22922102

  6. Involvement of JNK and Caspase Activation in Hoiamide A-Induced Neurotoxicity in Neocortical Neurons

    PubMed Central

    Cao, Zhengyu; Li, Xichun; Zou, Xiaohan; Greenwood, Michael; Gerwick, William H.; Murray, Thomas F.

    2015-01-01

    The frequent occurrence of Moorea producens (formerly Lyngbya majuscula) blooms has been associated with adverse effects on human health. Hoiamide A is a structurally unique cyclic depsipeptide isolated from an assemblage of the marine cyanobacteria M. producens and Phormidium gracile. We examined the influence of hoiamide A on neurite outgrowth in neocortical neurons and found that it suppressed neurite outgrowth with an IC50 value of 4.89 nM. Further study demonstrated that hoiamide A stimulated lactic acid dehydrogenase (LDH) efflux, nuclear condensation and caspase-3 activity with EC50 values of 3.66, 2.55 and 4.33 nM, respectively. These data indicated that hoiamide A triggered a unique neuronal death profile that involves both necrotic and apoptotic mechanisms. The similar potencies and similar time-response relationships between LDH efflux and caspase-3 activation/nuclear condensation suggested that both necrosis and apoptosis may derive from interaction with a common molecular target. The broad-spectrum caspase inhibitor, Z-VAD-FMK completely inhibited hoiamide A-induced neurotoxicity. Additionally, hoiamide A stimulated JNK phosphorylation, and a JNK inhibitor attenuated hoiamide A-induced neurotoxicity. Collectively, these data demonstrate that hoiamide A-induced neuronal death requires both JNK and caspase signaling pathways. The potent neurotoxicity and unique neuronal cell death profile of hoiamide A represents a novel neurotoxic chemotype from marine cyanobacteria. PMID:25675001

  7. Involvement of JNK and Caspase Activation in Hoiamide A-Induced Neurotoxicity in Neocortical Neurons.

    PubMed

    Cao, Zhengyu; Li, Xichun; Zou, Xiaohan; Greenwood, Michael; Gerwick, William H; Murray, Thomas F

    2015-01-01

    The frequent occurrence of Moorea producens (formerly Lyngbya majuscula) blooms has been associated with adverse effects on human health. Hoiamide A is a structurally unique cyclic depsipeptide isolated from an assemblage of the marine cyanobacteria M. producens and Phormidium gracile. We examined the influence of hoiamide A on neurite outgrowth in neocortical neurons and found that it suppressed neurite outgrowth with an IC50 value of 4.89 nM. Further study demonstrated that hoiamide A stimulated lactic acid dehydrogenase (LDH) efflux, nuclear condensation and caspase-3 activity with EC50 values of 3.66, 2.55 and 4.33 nM, respectively. These data indicated that hoiamide A triggered a unique neuronal death profile that involves both necrotic and apoptotic mechanisms. The similar potencies and similar time-response relationships between LDH efflux and caspase-3 activation/nuclear condensation suggested that both necrosis and apoptosis may derive from interaction with a common molecular target. The broad-spectrum caspase inhibitor, Z-VAD-FMK completely inhibited hoiamide A-induced neurotoxicity. Additionally, hoiamide A stimulated JNK phosphorylation, and a JNK inhibitor attenuated hoiamide A-induced neurotoxicity. Collectively, these data demonstrate that hoiamide A-induced neuronal death requires both JNK and caspase signaling pathways. The potent neurotoxicity and unique neuronal cell death profile of hoiamide A represents a novel neurotoxic chemotype from marine cyanobacteria. PMID:25675001

  8. Involvement of the histamine H1 receptor in the regulation of sympathetic nerve activity.

    PubMed

    Murakami, Manabu; Yoshikawa, Takeo; Nakamura, Tadaho; Ohba, Takayoshi; Matsuzaki, Yasushi; Sawamura, Daisuke; Kuwasako, Kenji; Yanagisawa, Teruyuki; Ono, Kyouichi; Nakaji, Shigeyuki; Yanai, Kazuhiko

    2015-03-13

    The histamine system is involved in the regulation of the autonomic nervous system. We used gene-targeted mice to investigate the role of histamine receptors in the regulation of the sympathetic nervous system. Reverse transcription-polymerase chain reaction (RT-PCR) analysis revealed histamine H1, H2, and H3 receptor expression in the superior cervical ganglion, which contains sympathetic nerve cell bodies. We measured the heart rate variability (HRV), the changes in the beat-to-beat heart rate, which is widely used to assess autonomic activity in the heart. H1 blockade attenuated the baroreflex-mediated changes in heart rate in wild-type (WT) mice, whereas the heart rate response to H2- and H3-specific blockers was unaffected. l-Histidine decarboxylase (HDC) expression in the superior cervical ganglion of H1R-null mice was higher than that in WT controls, whereas the enzyme levels in H2R- and H3R-null mice were not significantly different from those in the WT. All mutant mice (H1R-, H2R-, and H3R-null mice) showed normal electrocardiogram (ECG) patterns with little modification in ECG parameters and the expected response to the ?-adrenergic blocker propranolol. Similar to our findings in WT mice, H1 blockade attenuated the baroreflex-mediated heart rate change in H1R-null mice, whereas the heart rate response was unaffected in H2R- and H3R-null mice. The HRV analysis revealed relatively unstable RR intervals, an increased standard deviation of the interbeat interval (SDNN), and low-frequency (LF) component in H1R-null mice compared with the other groups, suggesting that sympathetic nerve activity was altered in H1R-null mice. Taken together, our findings indicate that H1 receptors play a major role in the regulation of sympathetic nerve activity. PMID:25680462

  9. Modulation of NCC activity by low and high K+ intake: insights into the signaling pathways involved

    PubMed Central

    Castañeda-Bueno, María; Cervantes-Perez, Luz Graciela; Rojas-Vega, Lorena; Arroyo-Garza, Isidora; Vázquez, Norma; Moreno, Erika

    2014-01-01

    Modulation of Na+-Cl? cotransporter (NCC) activity is essential to adjust K+ excretion in the face of changes in dietary K+ intake. We used previously characterized genetic mouse models to assess the role of Ste20-related proline-alanine-rich kinase (SPAK) and with-no-lysine kinase (WNK)4 in the modulation of NCC by K+ diets. SPAK knockin and WNK4 knockout mice were placed on normal-, low-, or high-K+-citrate diets for 4 days. The low-K+ diet decreased and high-K+ diet increased plasma aldosterone levels, but both diets were associated with increased phosphorylation of NCC (phospho-NCC, Thr44/Thr48/Thr53) and phosphorylation of SPAK/oxidative stress responsive kinase 1 (phospho-SPAK/OSR1, Ser383/Ser325). The effect of the low-K+ diet on SPAK phosphorylation persisted in WNK4 knockout and SPAK knockin mice, whereas the effects of ANG II on NCC and SPAK were lost in both mouse colonies. This suggests that for NCC activation by ANG II, integrity of the WNK4/SPAK pathway is required, whereas for the low-K+ diet, SPAK phosphorylation occurred despite the absence of WNK4, suggesting the involvement of another WNK (WNK1 or WNK3). Additionally, because NCC activation also occurred in SPAK knockin mice, it is possible that loss of SPAK was compensated by OSR1. The positive effect of the high-K+ diet was observed when the accompanying anion was citrate, whereas the high-KCl diet reduced NCC phosphorylation. However, the effect of the high-K+-citrate diet was aldosterone dependent, and neither metabolic alkalosis induced by bicarbonate, nor citrate administration in the absence of K+ increased NCC phosphorylation, suggesting that it was not due to citrate-induced metabolic alkalosis. Thus, the accompanying anion might modulate the NCC response to the high-K+ diet. PMID:24761002

  10. A mass spectrometric method to determine activities of enzymes involved in polyamine catabolism.

    PubMed

    Moriya, Shunsuke; Iwasaki, Kaori; Samejima, Keijiro; Takao, Koichi; Kohda, Kohfuku; Hiramatsu, Kyoko; Kawakita, Masao

    2012-10-20

    An analytical method for the determination of three polyamines (putrescine, spermidine, and spermine) and five acetylpolyamines [N(1)-acetylspermidine (N(1)AcSpd), N(8)-acetylspermidine (N(8)AcSpd), N(1)-acetylspermine, N(1),N(8)-diacetylspermidine, and N(1),N(12)-diacetylspermine] involved in the polyamine catabolic pathway has been developed using a hybrid tandem mass spectrometer. Heptafluorobutyryl (HFB) derivatives of these compounds and respective internal standards labeled with stable isotopes were analyzed simultaneously by TOF MS, based on peak areas appearing at appropriate m/z values. The isomers, N(1)AcSpd and N(8)AcSpd were determined from their fragment ions, the acetylamidopropyl and acetylamidobutyl groups, respectively, using MS/MS with (13)C(2)-N(1)AcSpd and (13)C(2)-N(8)AcSpd which have the (13)C(2)-acetyl group as an internal standard. The TOF MS method was successfully applied to measure the activity of enzymes involved in polyamine catabolic pathways, namely N(1)-acetylpolyamine oxidase (APAO), spermine oxidase (SMO), and spermidine/spermine N(1)-acetyltransferase (SSAT). The following natural substrates and products labeled with stable isotopes considering the application to biological samples were identified; for APAO, [4,9,12-(15)N(3)]-N(1)-acetylspermine and [1,4,8-(15)N(3)]spermidine ((15)N(3)-Spd), respectively; for SMO, [1,4,8,12-(15)N(4)]spermine and (15)N(3)-Spd, respectively; and for SSAT, (15)N(3)-Spd and [1,4,8-(15)N(3)]-N(1)-acetylspermidine, respectively. PMID:23021806

  11. EBV reactivation serological profile in primary Sjögren's syndrome: an underlying trigger of active articular involvement?

    PubMed

    Pasoto, Sandra Gofinet; Natalino, Renato Romera; Chakkour, Henrique Pires; Viana, Vilma Dos Santos Trindade; Bueno, Cleonice; Leon, Elaine Pires; Vendramini, Margarete Borges Gualhardo; Neto, Mauricio Levy; Bonfa, Eloisa

    2013-05-01

    Antibody to Epstein-Barr virus (EBV) early antigen diffuse (anti-EA-D) is associated with viral replication. However, their possible associations with clinical/therapeutic features in primary Sjögren's syndrome (pSS) were not established. We evaluated 100 pSS patients (American-European Criteria) and 89 age/gender/ethnicity-matched healthy controls. Disease activity was measured by EULAR Sjögren's Syndrome Disease Activity Index (ESSDAI). Antibodies to EBV (anti-VCA IgG/IgM, anti-EBNA-1 IgG, anti-EA-D IgG) were determined by ELISA. Patients and controls had comparable frequencies and mean levels of anti-VCA IgG (90 vs. 86.5 %, p = 0.501; 2.6 ± 1.1 vs. 2.5 ± 1.1 AU/mL, p = 0.737) and anti-EBNA-1 IgG (92 vs. 94.4 %, p = 0.576; 141.3 ± 69.8 vs. 135.6 ± 67.5 RU/mL, p = 0.464). Anti-VCA IgM was negative in all cases. Noteworthy, higher frequency and increased mean levels of anti-EA-D were observed in patients than controls (36 vs. 4.5 %, p < 0.0001; 38.6 ± 57.4 vs. 7.9 ± 26.3 RU/mL, p < 0.0001). Further analysis of patients with (n = 36) and without (n = 64) anti-EA-D revealed comparable age/gender/ethnicity (p ? 0.551), current prednisone dose (4.8 ± 6.9 vs. 5.1 ± 10.4 mg/day, p = 0.319), and current uses of prednisone (52.8 vs. 37.5 %, p = 0.148) and immunosuppressants (44.4 vs. 31.3 %, p = 0.201). ESSDAI values were comparable (p = 0.102), but joint activity was more frequent (25 vs. 9.4 %, p = 0.045) in anti-EA-D positive patients. Anti-EA-D antibodies were not associated with anti-Ro/SSA (p = 1.000), anti-La/SSB (p = 0.652), rheumatoid factor (p = 1.000), anti-?-fodrin (p = 0.390) or antiphospholipid antibodies (p = 0.573), not suggesting cross-reactivity. The higher anti-EA-D frequency associated with joint activity raises the possibility that a subclinical EBV reactivation may trigger or perpetuate the articular involvement in pSS. PMID:22955798

  12. The Effects of Adolescent Activities on Delinquency: A Differential Involvement Approach

    ERIC Educational Resources Information Center

    Wong, Siu Kwong

    2005-01-01

    T. Hirschi's (1969, "Causes of Delinquency." University of California Press, Berkeley, CA) control theory proposes that involvement, as an element of the social bond, should reduce delinquency. But, research studies have found that the effect of involvement is rather weak. This study reformulates Hirschi's involvement hypothesis by posing…

  13. Rural Schooling in Georgia: The Experiences of a Minority Community Service Organization Involved in Local School Decision-Making Activities

    ERIC Educational Resources Information Center

    Lowe, Cynthia Louise Altman

    2010-01-01

    This dissertation study was a descriptive case study of a minority community service organization whose members were actively involved in local school decision-making and activities in a rural Northeast Georgia community. Rural schools face unique challenges in light of current educational trends. To address the challenges, rural schools must…

  14. Understanding the Meaning African-American Men Give to Their Student Leadership Involvement and Engagement Activities in College

    ERIC Educational Resources Information Center

    Brooks, Karl A.

    2012-01-01

    The purpose of this qualitative, phenomenological study was to explore and gain a deeper understanding of the lived experiences and perceptions of African-American (A-A) men who are persisting in college and who demonstrate participation in co-curricular activities defined as student leadership involvement and engagement activities (SLIEA). The…

  15. Involvement of D-Asp in P450 aromatase activity and estrogen receptors in boar testis.

    PubMed

    Lamanna, C; Assisi, L; Botte, V; Di Fiore, M M

    2007-01-01

    Mammalian testis contains D-aspartic acid (D-Asp), which enhances testosterone production. D-Asp, on other hand, also stimulates 17beta-estradiol synthesis in the ovary of some lower vertebrates. We studied boar testis in order to determine if D-Asp intervenes in 17beta-estradiol synthesis in the testis of those mammals which produce significant amounts of estrogens as well as testosterone. The boar testis contains D-Asp (40 +/- 3.6 nmol/g tissue) which, according to immunohistological techniques, is localized mainly in Leydig cells, and, to a lesser extent, in sustentacular (Sertoli), peritubular and some germ cells. The enzyme P450aromatase is present in Leydig cells and few germ cells. In vitro experiments showed that the addition of D-Asp to testicular tissue extracts induced a significant increase of aromatase activity, as evaluated by testosterone conversion into 17beta-estradiol. The enzyme's K(m) was not affected by D-Asp (about 25 nM in both control and D-Asp added tests). On the basis of these results we suggest that, as in the ovary, D-Asp is involved in the local control of aromatase activity of boar testis and, therefore, it intervenes in the 17beta-estradiol production. In the testis, the D-Asp targets are presumably the Leydig cells, which having also a nuclear estrogen receptor are, in turn, one of the putative targets of the 17beta-estradiol that they produce (autocrine effect). PMID:17469225

  16. Lack of Involvement of CEP Adducts in TLR Activation and in Angiogenesis

    PubMed Central

    Gounarides, John; Cobb, Jennifer S.; Zhou, Jing; Cook, Frank; Yang, Xuemei; Yin, Hong; Meredith, Erik; Rao, Chang; Huang, Qian; Xu, YongYao; Anderson, Karen; De Erkenez, Andrea; Liao, Sha-Mei; Crowley, Maura; Buchanan, Natasha; Poor, Stephen; Qiu, Yubin; Fassbender, Elizabeth; Shen, Siyuan; Woolfenden, Amber; Jensen, Amy; Cepeda, Rosemarie; Etemad-Gilbertson, Bijan; Giza, Shelby; Mogi, Muneto; Jaffee, Bruce; Azarian, Sassan

    2014-01-01

    Proteins that are post-translationally adducted with 2-(?-carboxyethyl)pyrrole (CEP) have been proposed to play a pathogenic role in age-related macular degeneration, by inducing angiogenesis in a Toll Like Receptor 2 (TLR2)-dependent manner. We have investigated the involvement of CEP adducts in angiogenesis and TLR activation, to assess the therapeutic potential of inhibiting CEP adducts and TLR2 for ocular angiogenesis. As tool reagents, several CEP-adducted proteins and peptides were synthetically generated by published methodology and adduction was confirmed by NMR and LC-MS/MS analyses. Structural studies showed significant changes in secondary structure in CEP-adducted proteins but not the untreated proteins. Similar structural changes were also observed in the treated unadducted proteins, which were treated by the same adduction method except for one critical step required to form the CEP group. Thus some structural changes were unrelated to CEP groups and were artificially induced by the synthesis method. In biological studies, the CEP-adducted proteins and peptides failed to activate TLR2 in cell-based assays and in an in vivo TLR2-mediated retinal leukocyte infiltration model. Neither CEP adducts nor TLR agonists were able to induce angiogenesis in a tube formation assay. In vivo, treatment of animals with CEP-adducted protein had no effect on laser-induced choroidal neovascularization. Furthermore, in vivo inactivation of TLR2 by deficiency in Myeloid Differentiation factor 88 (Myd88) had no effect on abrasion-induced corneal neovascularization. Thus the CEP-TLR2 axis, which is implicated in other wound angiogenesis models, does not appear to play a pathological role in a corneal wound angiogenesis model. Collectively, our data do not support the mechanism of action of CEP adducts in TLR2-mediated angiogenesis proposed by others. PMID:25343517

  17. Involvement of Trichoderma Trichothecenes in the Biocontrol Activity and Induction of Plant Defense-Related Genes

    PubMed Central

    Malmierca, M. G.; Cardoza, R. E.; Alexander, N. J.; McCormick, S. P.; Hermosa, R.; Monte, E.

    2012-01-01

    Trichoderma species produce trichothecenes, most notably trichodermin and harzianum A (HA), by a biosynthetic pathway in which several of the involved proteins have significant differences in functionality compared to their Fusarium orthologues. In addition, the genes encoding these proteins show a genomic organization differing from that of the Fusarium tri clusters. Here we describe the isolation of Trichoderma arundinaceum IBT 40837 transformants which have a disrupted or silenced tri4 gene, a gene encoding a cytochrome P450 monooxygenase that oxygenates trichodiene to give rise to isotrichodiol, and the effect of tri4 gene disruption and silencing on the expression of other tri genes. Our results indicate that the tri4 gene disruption resulted in a reduced antifungal activity against Botrytis cinerea and Rhizoctonia solani and also in a reduced ability to induce the expression of tomato plant defense-related genes belonging to the salicylic acid (SA) and jasmonate (JA) pathways against B. cinerea, in comparison to the wild-type strain, indicating that HA plays an important function in the sensitization of Trichoderma-pretreated plants against this fungal pathogen. Additionally, the effect of the interaction of T. arundinaceum with B. cinerea or R. solani and with tomato seedlings on the expressions of the tri genes was studied. PMID:22562989

  18. Current Practice of Public Involvement Activities in Biomedical Research and Innovation: A Systematic Qualitative Review

    PubMed Central

    Lander, Jonas; Hainz, Tobias; Hirschberg, Irene; Strech, Daniel

    2014-01-01

    Background A recent report from the British Nuffield Council on Bioethics associated ‘emerging biotechnologies’ with a threefold challenge: 1) uncertainty about outcomes, 2) diverse public views on the values and implications attached to biotechnologies and 3) the possibility of creating radical changes regarding societal relations and practices. To address these challenges, leading international institutions stress the need for public involvement activities (PIAs). The objective of this study was to assess the state of PIA reports in the field of biomedical research. Methods PIA reports were identified via a systematic literature search. Thematic text analysis was employed for data extraction. Results After filtering, 35 public consultation and 11 public participation studies were included in this review. Analysis and synthesis of all 46 PIA studies resulted in 6 distinguishable PIA objectives and 37 corresponding PIA methods. Reports of outcome translation and PIA evaluation were found in 9 and 10 studies respectively (20% and 22%). The paper presents qualitative details. Discussion The state of PIAs on biomedical research and innovation is characterized by a broad range of methods and awkward variation in the wording of objectives. Better comparability of PIAs might improve the translation of PIA findings into further policy development. PIA-specific reporting guidelines would help in this regard. The modest level of translation efforts is another pointer to the “deliberation to policy gap”. The results of this review could inform the design of new PIAs and future efforts to improve PIA comparability and outcome translation. PMID:25469705

  19. Involvement of kinins in hyperresponsiveness induced by platelet activating factor in the human nasal airway

    PubMed Central

    Turner, P J; Dear, J W; Foreman, J C

    2000-01-01

    The aim of this study was to investigate the role of kinins in the development of nasal hyperresponsiveness induced by platelet activating factor (PAF) in normal human subjects. Intranasal administration of PAF, 60??g, induced an increased responsiveness to histamine, 200??g per nostril, 6?h later. This effect was abolished by pretreatment with the bradykinin B2 receptor antagonists icatibant and [1-adamantaneacetyl-D-Arg0,Hyp3,?-(2-thienyl)-Ala5,8,D-Phe7]-bradykinin ([Ad]-BK), both at 200??g, every 2?h following PAF administration. In a separate experiment, utilizing the same protocol, nasal lavage was used to measure the release of mediators into the nasal cavity following treatment with PAF. PAF increased the levels of eosinophil cationic protein (ECP) and kinin detected in the lavage samples, compared with a saline control. The levels of these mediators were reduced by pretreatment with either icatibant or [Ad]-BK. Administration of lyso-PAF, 60??g intranasally, did not cause a rise in kinin or ECP levels in nasal lavage fluid. Exogenous bradykinin, 500??g, or a saline control, applied topically to the nasal mucosa every 30?min for 2?h, failed to cause hyperresponsiveness to histamine. We conclude that bradykinin itself does not cause hyperresponsiveness, but is involved in the hyperresponsiveness induced by PAF in the human nasal airway. PMID:10711351

  20. Involvement of Trichoderma trichothecenes in the biocontrol activity and induction of plant defense-related genes.

    PubMed

    Malmierca, M G; Cardoza, R E; Alexander, N J; McCormick, S P; Hermosa, R; Monte, E; Gutiérrez, S

    2012-07-01

    Trichoderma species produce trichothecenes, most notably trichodermin and harzianum A (HA), by a biosynthetic pathway in which several of the involved proteins have significant differences in functionality compared to their Fusarium orthologues. In addition, the genes encoding these proteins show a genomic organization differing from that of the Fusarium tri clusters. Here we describe the isolation of Trichoderma arundinaceum IBT 40837 transformants which have a disrupted or silenced tri4 gene, a gene encoding a cytochrome P450 monooxygenase that oxygenates trichodiene to give rise to isotrichodiol, and the effect of tri4 gene disruption and silencing on the expression of other tri genes. Our results indicate that the tri4 gene disruption resulted in a reduced antifungal activity against Botrytis cinerea and Rhizoctonia solani and also in a reduced ability to induce the expression of tomato plant defense-related genes belonging to the salicylic acid (SA) and jasmonate (JA) pathways against B. cinerea, in comparison to the wild-type strain, indicating that HA plays an important function in the sensitization of Trichoderma-pretreated plants against this fungal pathogen. Additionally, the effect of the interaction of T. arundinaceum with B. cinerea or R. solani and with tomato seedlings on the expressions of the tri genes was studied. PMID:22562989

  1. Involvement of plant endogenous ABA in Bacillus megaterium PGPR activity in tomato plants

    PubMed Central

    2014-01-01

    Background Plant growth-promoting rhizobacteria (PGPR) are naturally occurring soil bacteria which benefit plants by improving plant productivity and immunity. The mechanisms involved in these processes include the regulation of plant hormone levels such as ethylene and abscisic acid (ABA). The aim of the present study was to determine whether the activity of Bacillus megaterium PGPR is affected by the endogenous ABA content of the host plant. The ABA-deficient tomato mutants flacca and sitiens and their near-isogenic wild-type parental lines were used. Growth, stomatal conductance, shoot hormone concentration, competition assay for colonization of tomato root tips, and root expression of plant genes expected to be modulated by ABA and PGPR were examined. Results Contrary to the wild-type plants in which PGPR stimulated growth rates, PGPR caused growth inhibition in ABA-deficient mutant plants. PGPR also triggered an over accumulation of ethylene in ABA-deficient plants which correlated with a higher expression of the pathogenesis-related gene Sl-PR1b. Conclusions Positive correlation between over-accumulation of ethylene and a higher expression of Sl-PR1b in ABA-deficient mutant plants could indicate that maintenance of normal plant endogenous ABA content may be essential for the growth promoting action of B. megaterium by keeping low levels of ethylene production. PMID:24460926

  2. Identification of Tyrosine Residues in Constitutively Activated Fibroblast Growth Factor Receptor 3 Involved in Mitogenesis, Stat Activation, and Phosphatidylinositol 3-Kinase Activation

    PubMed Central

    Hart, Kristen C.; Robertson, Scott C.; Donoghue, Daniel J.

    2001-01-01

    Fibroblast growth factor receptor 3 (FGFR3) mutations are frequently involved in human developmental disorders and cancer. Activation of FGFR3, through mutation or ligand stimulation, results in autophosphorylation of multiple tyrosine residues within the intracellular domain. To assess the importance of the six conserved tyrosine residues within the intracellular domain of FGFR3 for signaling, derivatives were constructed containing an N-terminal myristylation signal for plasma membrane localization and a point mutation (K650E) that confers constitutive kinase activation. A derivative containing all conserved tyrosine residues stimulates cellular transformation and activation of several FGFR3 signaling pathways. Substitution of all nonactivation loop tyrosine residues with phenylalanine rendered this FGFR3 construct inactive, despite the presence of the activating K650E mutation. Addition of a single tyrosine residue, Y724, restored its ability to stimulate cellular transformation, phosphatidylinositol 3-kinase activation, and phosphorylation of Shp2, MAPK, Stat1, and Stat3. These results demonstrate a critical role for Y724 in the activation of multiple signaling pathways by constitutively activated mutants of FGFR3. PMID:11294897

  3. Family involvement in music impacts participation of children with cochlear implants in music education and music activities.

    PubMed

    Driscoll, Virginia; Gfeller, Kate; Tan, Xueli; See, Rachel L; Cheng, Hsin-Yi; Kanemitsu, Mikiko

    2014-11-28

    Objective Children with cochlear implants (CIs) participate in musical activities in school and daily lives. Considerable variability exists regarding the amount of music involvement and enjoyment. Using the Music Engagement Questionnaire-Preschool/Elementary (MEQ-P/E), we wanted to determine patterns of musical participation and the impact of familial factors on engagement. Methods Parents of 32 children with CIs (16 preschool and 16 elementary) completed a questionnaire regarding the musical involvement of their child with an implant and a normal-hearing (NH) sibling (if one existed). We compared CI children's involvement to that of their NH siblings as well as across groups of children with and without CIs. Correlations between parent ratings of music importance, demographic factors, and involvement of CI and NH children were conducted within and across groups. Results No significant differences were found between children with CIs and NH siblings, meaning children from the same family showed similar levels of musical involvement. When compared at the same developmental stage, no significant differences were found between preschool children with and without CIs. Parents who rated the importance of music as 'low' or 'middle' had children (NH and CI) who were less involved in music activities. Children whose parents rated music importance as 'high' were involved in monthly to weekly music activities with 81.25% reporting daily music listening. Conclusion Despite a less-than-ideal auditory signal for music, preschool and school-aged CI children enjoy and are involved in musical experiences. Families who enjoy and spend a greater amount of time involved in music tend to have children who also engage more actively in music. PMID:25431978

  4. Residues involved in the pore-forming activity of the Clostridium perfringens iota toxin.

    PubMed

    Knapp, Oliver; Maier, Elke; Waltenberger, Eva; Mazuet, Christelle; Benz, Roland; Popoff, Michel R

    2015-02-01

    Clostridium perfringens iota toxin is a binary toxin that is organized into enzyme (Ia) and binding (Ib) components. Ib forms channels in lipid bilayers and mediates the transport of Ia into the target cells. Here we show that Ib residues 334-359 contain a conserved pattern of alternating hydrophobic and hydrophilic residues forming two amphipathic ?-strands involved in membrane insertion and channel formation. This stretch of amino acids shows remarkable structural and functional analogies with the ?-pore-forming domain of C. perfringens epsilon toxin. Several mutations within the two amphipathic ?-strands affected pore formation, single-channel conductance and ion selectivity (S339E-S341E, Q345H N346E) confirming their involvement in channel formation. F454 of Ib corresponds to the ?-clamp F427 of anthrax protective antigen and F428 of C2II binary toxins. The mutation F454A resulted in a loss of cytotoxicity and strong increase in single-channel conductance (500 pS as compared with 85?pS in 1 M KCl) with a slight decrease in cation selectivity, indicating that the ?-clamp is highly conserved and crucial for binary toxin activity. In contrast, the mutants Q367D, N430D, L443E had no or only minor effects on Ib properties, while T360I, T360A and T360W caused a dramatic effect on ion selectivity and single-channel conductance, indicating gross disturbance of the oligomer structure. This suggests that, at least in the iota toxin family, T360 has a structural role in the pore organization. Moreover, introduction of charged residues within the channel (S339E-S341E) or in the vestibule (Q367D, N430D and L443E) had virtually no effect on chloroquine or Ia binding, whereas F454A, T360I, T360A and T360W strongly decreased the chloroquine and Ia affinity to Ib. These results support that distinct residues within the vestibule interact with chloroquine and Ia or are responsible for channel structure, while the channel lining amino acids play a less important role. PMID:25266274

  5. Plasminogen activator inhibitor-1 is involved in impaired bone repair associated with diabetes in female mice.

    PubMed

    Mao, Li; Kawao, Naoyuki; Tamura, Yukinori; Okumoto, Katsumi; Okada, Kiyotaka; Yano, Masato; Matsuo, Osamu; Kaji, Hiroshi

    2014-01-01

    Previous studies suggest that fracture healing is impaired in diabetes; however, the underlying mechanism remains unclear. Here, we investigated the roles of plasminogen activator inhibitor-1 (PAI-1) in the impaired bone repair process by using streptozotocin (STZ)-induced diabetic female wild-type (PAI-1+/+) and PAI-1-deficient (PAI-1-/-) mice. Bone repair and the number of alkaline phosphatase (ALP)-positive cells at the site of a femoral bone damage were comparable in PAI-1+/+ and PAI-1-/- mice without STZ treatment. Although the bone repair process was delayed by STZ treatment in PAI-1+/+ mice, this delayed bone repair was blunted in PAI-1-/- mice. The reduction in the number of ALP-positive cells at the site of bone damage induced by STZ treatment was attenuated in PAI-1-/- mice compared to PAI-1+/+ mice. On the other hand, PAI-1 deficiency increased the levels of ALP and type I collagen mRNA in female mice with or without STZ treatment, and the levels of Osterix and osteocalcin mRNA, suppressed by diabetic state in PAI-1+/+ mice, were partially protected in PAI-1-/- mice. PAI-1 deficiency did not affect formation of the cartilage matrix and the levels of types II and X collagen and aggrecan mRNA suppressed by STZ treatment, although PAI-1 deficiency increased the expression of chondrogenic markers in mice without STZ treatment. The present study indicates that PAI-1 is involved in the impaired bone repair process induced by the diabetic state in part through a decrease in the number of ALP-positive cells. PMID:24651693

  6. Personal involvement is related to increased search motivation and associated with activity in left BA44—a pilot study

    PubMed Central

    Schaefer, Michael; Rumpel, Franziska; Sadrieh, Abdolkarim; Reimann, Martin; Denke, Claudia

    2015-01-01

    Numerous studies explore consumer perception of brands in a more or less passive way. This may still be representative for many situations or decisions we make each day. Nevertheless, sometimes we often actively search for and use information to make informed and reasoned choices, thus implying a rational and thinking consumer. Researchers suggested describing this distinction as low relative to high involvement consumer behavior. Although the involvement concept has been widely used to explain consumer behavior, behavioral and neural correlates of this concept are poorly understood. The current study aims to describe a behavioral measure that is associated with high involvement, the length of search behavior. A second aim of this study was to explore brain activations associated with involvement by employing functional magnetic resonance imaging (fMRI). We presented participants information cues for different products and told them that they had to answer questions with respect to these products at the end of the experiment. Participants were free to stop the information search if they think they gathered enough information or to continue with collecting information. Behavioral results confirmed our hypothesis of a relationship between searching behavior and personal involvement by demonstrating that the length of search correlated significantly with the degree of personal involvement of the participants. fMRI data revealed that personal involvement was associated with activation in BA44. Since this brain region is known to be involved in semantic memory, the results of this pilot study suggest that high involvement consumer behavior may be linked to cognitive load and attention towards a product. PMID:25859200

  7. Differential Involvement of Amygdala and Cortical NMDA Receptors Activation upon Encoding in Odor Fear Memory

    ERIC Educational Resources Information Center

    Hegoburu, Chloé; Parrot, Sandrine; Ferreira, Guilaume; Mouly, Anne-Marie

    2014-01-01

    Although the basolateral amygdala (BLA) plays a crucial role for the acquisition of fear memories, sensory cortices are involved in their long-term storage in rats. However, the time course of their respective involvement has received little investigation. Here we assessed the role of the glutamatergic N-methyl-D-aspartate (NMDA) receptors in the…

  8. Self-definitions of Gang Membership and Involvement in Delinquent Activities

    Microsoft Academic Search

    BETH BJERREGAARD

    2002-01-01

    There is significant disagreement among researchers as to the appropriate concep- tual and operational definitions of gang membership. One of the key issues involves the validity of allowing respondents to identify themselves as gang members. This re- search examines the construct validity of gang membership by examining the relation- ship between various methods of operationalizing gang membership and delinquent involvement.

  9. 48 CFR 3452.224-71 - Notice about research activities involving human subjects.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...to the Department: (i) Human subjects' involvement and characteristics...individually identifiable living human subjects in the form of specimens...the subjects are reasonable in relation to the importance of the knowledge...sites: If research involving human subjects will take place...

  10. 48 CFR 3452.224-71 - Notice about research activities involving human subjects.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...to the Department: (i) Human subjects' involvement and characteristics...individually identifiable living human subjects in the form of specimens...the subjects are reasonable in relation to the importance of the knowledge...sites: If research involving human subjects will take place...

  11. 48 CFR 3452.224-71 - Notice about research activities involving human subjects.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...to the Department: (i) Human subjects' involvement and characteristics...individually identifiable living human subjects in the form of specimens...the subjects are reasonable in relation to the importance of the knowledge...sites: If research involving human subjects will take place...

  12. Embryonic liver fodrin involved in hepatic stellate cell activation and formation of regenerative nodule in liver cirrhosis

    PubMed Central

    Wang, Zhijun; Liu, Fang; Tu, Wei; Chang, Ying; Yao, Jinjian; Wu, Wei; Jiang, Xiang; He, Xingxing; Lin, Jusheng; Song, Yuhu

    2012-01-01

    Abstract Transforming growth factor (TGF) ?1 plays a critical role in liver fibrosis. Previous studies demonstrated embryonic liver fodrin (ELF), a ?-spectrin was involved in TGF-?/Smad signalling pathway as Smad3/4 adaptor. Here we investigate the role of ELF in pathogenesis of liver cirrhosis. In carbon tetrachloride (CCl4)-induced mice model of liver cirrhosis, ELF is up-regulated in activated hepatic stellate cells (HSCs), and down-regulated in regenerative hepatocytes of cirrhotic nodules. In activated HSCs in vitro, reduction of ELF expression mediated by siRNA leads to the inhibition of HSC activation and procollagen I expression. BrdU assay demonstrates that down-regulation of ELF expression does not inhibit proliferation of activated HSCs in vitro. Immunostaining of cytokeratin 19 and Ki67 indicates that regenerative hepatocytes in cirrhotic liver are derived from hepatic progenitor cells (HPC). Further study reveals that HPC expansion occurs as an initial phase, before the reduction of ELF expression in regenerative hepatocytes. Regenerative hepatocytes in cirrhotic liver show the change in proliferative activity and expression pattern of proteins involved in G1/S transition, which suggests the deregulation of cell cycle in regenerative hepatocytes. Finally, we find that ELF participates in TGF-?/Smad signal in activated HSCs and hepatocytes through regulating the localization of Smad3/4. These data reveal that ELF is involved in HSC activation and the formation of regenerative nodules derived from HPC in cirrhotic liver. PMID:21388516

  13. Active involvement of Ca2+ in mitotic progression of Swiss 3T3 fibroblasts

    PubMed Central

    1990-01-01

    Global Ca2+ transients have been observed to precede nuclear envelope breakdown and the onset of anaphase in Swiss 3T3 fibroblasts in 8% (vol/vol) FBS. The occurrence of these Ca2+ transients was dependent on intracellular stores. These Ca2+ transients could be (a) abolished by serum removal without halting mitosis, and (b) eliminated by increasing intracellular Ca2+ buffering capacity through loading the cells with 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid (BAPTA) buffer, via the tetra(acetoxymethyl) ester, without hindering the transition into anaphase. Microinjection of sufficient concentrations of BAPTA buffer could block nuclear envelope breakdown. Pulses of Ca2+ generated by flash photolysis of intracellularly trapped nitr-5, a "caged" Ca2+, could precipitate precocious nuclear envelope breakdown in prophase cells. In metaphase cells, photochemically generated Ca2+ pulses could cause changes in the appearance of the chromosomes, but the length of time required for cells to make the transition from metaphase to anaphase remained essentially unchanged regardless of whether a Ca2+ pulse was photoreleased during metaphase. The results from these photorelease experiments were not dependent on the presence of serum in the medium. Discharging intracellular Ca2+ stores with ionomycin in the presence of 1.8 mM extracellular Ca2+ doubled the time for cells to pass from late metaphase into anaphase, whereas severe Ca2+ deprivation by treatment with ionomycin in EGTA-containing medium halted mitosis. Our results collectively indicate that Ca2+ is actively involved in nuclear envelope breakdown, but Ca2+ signals are likely unnecessary for the metaphase-anaphase transition in Swiss 3T3 fibroblasts. Additional studies of intracellular Ca2+ concentrations in mitotic REF52 and PtK1 cells revealed that Ca2+ transients are not observed at all mitotic stages in all cells. The absence of observable global Ca2+ transients, where calcium buffers can block and pulses of Ca2+ can advance mitotic stages, may imply that the relevant Ca2+ movements are too local to be detected. PMID:2114410

  14. Parent Involvement

    E-print Network

    Howard, Jeff W.

    2005-05-10

    To be successful, a 4-H program must have parent involvement. Although 4-H leaders and Extension agents may interest young people in becoming members, they need the parents' goodwill and support to keep them interested, enthusiastic and active. Here...

  15. Atmospheric science is the study of short-term weather and long-term climate, involving activities such as weather

    E-print Network

    Saldin, Dilano

    Atmospheric science is the study of short-term weather and long-term climate, involving activities such as weather forecasting, climate projections, air quality modeling, data analysis, and basic and applied. The program maintains strong ties with regional employers in both the private sector and the National Weather

  16. 162 Electrical and Computer Engineering 163 Courses and projects that actively involve them in their own education and

    E-print Network

    Richards-Kortum, Rebecca

    162 Electrical and Computer Engineering 163 · Courses and projects that actively involve them · A broad education outside of engineering and science that emphasizes the role of electrical and computer of technology Graduate and undergraduate programs in electrical and computer engineering offer concentrations

  17. Speaker bios Richard Warnecke is Emeritus Professor at the University of Illinois at Chicago. He has been actively involved in

    E-print Network

    Illinois at Chicago, University of

    in the Institute for Social Research, the Department of Psychology, and the Ross School of Business (1993­2013). He for the Environment, Director of Stanford's Political Psychology Research Group, and Research Psychologist at the U has been actively involved in cancer control research for more than 40 years and has a long

  18. Expectations of Rock Music Consumption for Entertainment and Information Relative to the Active Involvement of the User.

    ERIC Educational Resources Information Center

    Rouner, Donna; Noyes, Amy

    Before examining potentially negative effects of rock music on adolescents, it is necessary to demonstrate links between adolescent motivations for consuming rock music and active involvement relative to that use and also to consider how much rock listeners rely on rock music as a source for information about values, beliefs, and social…

  19. To provide guidelines for the presence of children in the work place for other than official University activities involving children.

    E-print Network

    Hutcheon, James M.

    Purpose To provide guidelines for the presence of children in the work place for other than official University activities involving children. Policy Employees with dependent children are expected to make regular arrangements for proper care of their children while at work. The University must consider

  20. Belinostat-induced apoptosis and growth inhibition in pancreatic cancer cells involve activation of TAK1-AMPK signaling axis

    SciTech Connect

    Wang, Bing, E-mail: wangbin69@yahoo.com; Wang, Xin-bao; Chen, Li-yu; Huang, Ling; Dong, Rui-zen

    2013-07-19

    Highlights: •Belinostat activates AMPK in cultured pancreatic cancer cells. •Activation of AMPK is important for belinostat-induced cytotoxic effects. •ROS and TAK1 are involved in belinostat-induced AMPK activation. •AMPK activation mediates mTOR inhibition by belinostat. -- Abstract: Pancreatic cancer accounts for more than 250,000 deaths worldwide each year. Recent studies have shown that belinostat, a novel pan histone deacetylases inhibitor (HDACi) induces apoptosis and growth inhibition in pancreatic cancer cells. However, the underlying mechanisms are not fully understood. In the current study, we found that AMP-activated protein kinase (AMPK) activation was required for belinostat-induced apoptosis and anti-proliferation in PANC-1 pancreatic cancer cells. A significant AMPK activation was induced by belinostat in PANC-1 cells. Inhibition of AMPK by RNAi knockdown or dominant negative (DN) mutation significantly inhibited belinostat-induced apoptosis in PANC-1 cells. Reversely, AMPK activator AICAR and A-769662 exerted strong cytotoxicity in PANC-1 cells. Belinostat promoted reactive oxygen species (ROS) production in PANC-1 cells, increased ROS induced transforming growth factor-?-activating kinase 1 (TAK1)/AMPK association to activate AMPK. Meanwhile, anti-oxidants N-Acetyl-Cysteine (NAC) and MnTBAP as well as TAK1 shRNA knockdown suppressed belinostat-induced AMPK activation and PANC-1 cell apoptosis. In conclusion, we propose that belinostat-induced apoptosis and growth inhibition require the activation of ROS-TAK1-AMPK signaling axis in cultured pancreatic cancer cells.

  1. A qualitative study of the activities performed by people involved in clinical decision support: recommended practices for success

    PubMed Central

    Wright, Adam; Ash, Joan S; Erickson, Jessica L; Wasserman, Joe; Bunce, Arwen; Stanescu, Ana; St Hilaire, Daniel; Panzenhagen, Morgan; Gebhardt, Eric; McMullen, Carmit; Middleton, Blackford; Sittig, Dean F

    2014-01-01

    Objective To describe the activities performed by people involved in clinical decision support (CDS) at leading sites. Materials and methods We conducted ethnographic observations at seven diverse sites with a history of excellence in CDS using the Rapid Assessment Process and analyzed the data using a series of card sorts, informed by Linstone's Multiple Perspectives Model. Results We identified 18 activities and grouped them into four areas. Area 1: Fostering relationships across the organization, with activities (a) training and support, (b) visibility/presence on the floor, (c) liaising between people, (d) administration and leadership, (e) project management, (f) cheerleading/buy-in/sponsorship, (g) preparing for CDS implementation. Area 2: Assembling the system with activities (a) providing technical support, (b) CDS content development, (c) purchasing products from vendors (d) knowledge management, (e) system integration. Area 3: Using CDS to achieve the organization's goals with activities (a) reporting, (b) requirements-gathering/specifications, (c) monitoring CDS, (d) linking CDS to goals, (e) managing data. Area 4: Participation in external policy and standards activities (this area consists of only a single activity). We also identified a set of recommendations associated with these 18 activities. Discussion All 18 activities we identified were performed at all sites, although the way they were organized into roles differed substantially. We consider these activities critical to the success of a CDS program. Conclusions A series of activities are performed by sites strong in CDS, and sites adopting CDS should ensure they incorporate these activities into their efforts. PMID:23999670

  2. Mitogen-Activated Protein Kinase Cascade Is Involved in Endothelin1Induced Rat Puerperal Uterine Contraction

    Microsoft Academic Search

    AKIKO KIMURA; MASAHIDE OHMICHI; TAKASHI TAKEDA; HIROHISA KURACHI; HIROMASA IKEGAMI; KOJI KOIKE; KANJI MASUHARA; JUN HAYAKAWA; TOHRU KANZAKI; MAMORU KOBAYASHI; MASUO AKABANE; MASAKI INOUE; AKIRA MIYAKE; YUJI MURATA

    1999-01-01

    The regulation of mitogen-activated protein (MAP) kinase by en- dothelin-1 (ET-1) in cultured rat puerperal uterine myometrial cells was investigated. ET-1 caused the rapid stimulation of MAP kinase activity. ET-1-induced MAP kinase activation is neither extracellular Ca21- nor intracellular Ca21-dependent. ET-1 stimulation also led to an increase in phosphorylation of son-of-sevenless (SOS), and trans- fection of dominant negative SOS attenuated

  3. Activity-Dependent Dendritic Spine Shrinkage and Growth Involve Downregulation of Cofilin via Distinct Mechanisms

    PubMed Central

    Calabrese, Barbara; Saffin, Jean-Michel; Halpain, Shelley

    2014-01-01

    A current model posits that cofilin-dependent actin severing negatively impacts dendritic spine volume. Studies suggested that increased cofilin activity underlies activity-dependent spine shrinkage, and that reduced cofilin activity induces activity-dependent spine growth. We suggest instead that both types of structural plasticity correlate with decreased cofilin activity. However, the mechanism of inhibition determines the outcome for spine morphology. RNAi in rat hippocampal cultures demonstrates that cofilin is essential for normal spine maintenance. Cofilin-F-actin binding and filament barbed-end production decrease during the early phase of activity-dependent spine shrinkage; cofilin concentration also decreases. Inhibition of the cathepsin B/L family of proteases prevents both cofilin loss and spine shrinkage. Conversely, during activity-dependent spine growth, LIM kinase stimulates cofilin phosphorylation, which activates phospholipase D-1 to promote actin polymerization. These results implicate novel molecular mechanisms and prompt a revision of the current model for how cofilin functions in activity-dependent structural plasticity. PMID:24740405

  4. Activated spinal astrocytes are involved in the maintenance of chronic widespread mechanical hyperalgesia after cast immobilization

    PubMed Central

    2014-01-01

    Background In the present study, we examined spinal glial cell activation as a central nervous system mechanism of widespread mechanical hyperalgesia in rats that experienced chronic post-cast pain (CPCP) 2 weeks after cast immobilization. Activated spinal microglia and astrocytes were investigated immunohistologically in lumbar and coccygeal spinal cord segments 1 day, 5 weeks, and 13 weeks following cast removal. Results In the lumbar cord, astrocytes were activated after microglia. Astrocytes also were activated after microglia in the coccygeal cord, but with a delay that was longer than that observed in the lumbar cord. This activation pattern paralleled the observation that mechanical hyperalgesia occurred in the hindleg or the hindpaw before the tail. The activating transcription factor 3 (ATF3) immune response in dorsal root ganglia (DRG) on the last day of cast immobilization suggested that nerve damage might not occur in CPCP rats. The neural activation assessed by the phosphorylated extracellular signal-regulated kinase (pERK) immune response in DRG arose 1 day after cast removal. In addition, L-?-aminoadipate (L-?-AA), an inhibitor of astrocyte activation administered intrathecally 5 weeks after cast removal, inhibited mechanical hyperalgesia in several body parts including the lower leg skin and muscles bilaterally, hindpaws, and tail. Conclusions These findings suggest that activation of lumbar cord astrocytes is an important factor in widespread mechanical hyperalgesia in CPCP. PMID:24456903

  5. Analytica Chimica Acta 521 (2004) 17 Monitoring the three enzymatic activities involved in

    E-print Network

    Krylov, Sergey

    2004-01-01

    are important oncogenes that are involved in more than 30% of human cancers. To become functional, Ras proteins-targeting anti-cancer agents. © 2004 Elsevier B.V. All rights reserved. Keywords: Ras proteins; Protein players in a signal transduc- tion pathway that controls cell proliferation. Mutated ras genes are found

  6. Optical Topography of Evoked Brain Activity during Mental Tasks Involving Whole Number Operations

    ERIC Educational Resources Information Center

    Ortiz, Enrique

    2014-01-01

    Students start to memorize arithmetic facts from early elementary school mathematics activities. Their fluency or lack of fluency with these facts could affect their efforts as they carry out mental calculations as adults. This study investigated participants' levels of brain activation and possible reasons for these levels as they solved…

  7. Stress induced morphological microglial activation in the rodent brain: Involvement of interleukin-18

    Microsoft Academic Search

    S. Sugama; M. Fujita; M. Hashimoto; B. Conti

    2007-01-01

    The present study investigated the possibility that acute stress might activate microglial cells. Wistar rats were exposed to 2 h period of restraint combined with water immersion stress prior to brain analysis by immunohistochemistry with OX-42, a marker of complement receptor CR3. A single session of stress provoked robust morphological microglial activation in the thalamus, hypothalamus, hippocampus, substantia nigra and

  8. Discovering the Thermodynamics of Simultaneous Equilibria: An Entropy Analysis Activity Involving Consecutive Equilibria

    ERIC Educational Resources Information Center

    Bindel, Thomas H.

    2007-01-01

    An activity is presented in which the thermodynamics of simultaneous, consecutive equilibria are explored. The activity is appropriate for second-year high school or AP chemistry. Students discover that a reactant-favored (entropy-diminishing or endergonic) reaction can be caused to happen if it is coupled with a product-favored reaction of…

  9. Developmental Benefits of Extracurricular Involvement: Do Peer Characteristics Mediate the Link between Activities and Youth Outcomes?

    ERIC Educational Resources Information Center

    Fredricks, Jennifer A.; Eccles, Jacquelynn S.

    2005-01-01

    In this article, we test: (a) the relation between school-based extracurricular participation and indicators of positive and negative development across a range of activity contexts, and (b) a mediation model linking activity participation, prosocial peers, and development. Extensive survey information was collected from a predominately White…

  10. Temporal-Order Judgment of Audiovisual Events Involves Network Activity Between Parietal and Prefrontal Cortices

    E-print Network

    Dhamala, Mukesh

    this perception of temporal order, the right dorsolateral prefrontal cortex coordinated activity with the right and Prefrontal Cortices Bhim Mani Adhikari,1 Eli S. Goshorn,1,2 Bidhan Lamichhane,1 and Mukesh Dhamala1 in the multisensory domain underlies a network activity be- tween parietal and prefrontal cortices unlike the regional

  11. Barriers to the involvement of the elderly in public services to promote physical activity.

    PubMed

    Ribeiro, Renato Mendonça; Tribess, Sheilla; Santos, Andrêza Soares Dos; Pinto, Lélia Lessa Teixeira; Ribeiro, Maria da Conceição Lopes; Roza, Liliane Beatriz; Virtuoso Júnior, Jair Sindra

    2015-03-01

    The aim of this study was to examine the sociodemographic, health and behavioural characteristics related to non-participation of elderly people in activities offered by the program PROETI Health of Uberaba, Minas Gerais state. Observational study, case-control design with pairing 1:1 and sample composed of 220 elderly 60-80 years. Binary Logistic Regression was used to identify the sociodemographic, health and behavioral factors associated with non-engagement of non-users to the program. After hierarchical analysis, the non-engagement of the elderly in the program activities was associated with depressive symptoms, insufficient physical activity in the domain of leisure and reduced self-efficacy for performing moderate or vigorous physical activity. The characteristics identified in this study should receive priority attention in the formulation of community programs targeted at promoting physical activity for elderly people. PMID:25760114

  12. ACTIVATION OF STIM1-ORAI1 INVOLVES AN INTRAMOLECULAR SWITCHING MECHANISM*

    PubMed Central

    Korzeniowski, Marek K.; Manjarrés, Isabel Martín; Varnai, Peter; Balla, Tamas

    2012-01-01

    SUMMARY The stromal interaction molecule, STIM1 regulates Ca2+ entry via Orai1 channels in response to decreased concentration of ER luminal Ca2+. In search of a mechanism that switches the cytoplasmic aspect of STIM1 from an inactive to an active state, we identified an acidic motif within the STIM1 coiled-coil region that keeps the Ca2+ activation domain (CAD/SOAR) inactive. The STIM1 acidic motif shows significant homology to the C-terminal coiled-coil segment of Orai1, the postulated site of interaction with STIM1. Mutations within the acidic region make STIM1 constitutively active while those within a short basic segment of CAD/SOAR prevent Orai1 activation. We propose that during STIM1 activation, the CAD/SOAR domain is released from an intramolecular clamp allowing the basic segment to activate Orai1 channels. This evolutionary conserved activation mechanism of STIM1 resembles the regulation of protein kinases by intramolecular silencing with pseudosubstrate binding. PMID:21081754

  13. NIK is involved in constitutive activation of the alternative NF-{kappa}B pathway and proliferation of pancreatic cancer cells

    SciTech Connect

    Nishina, Takashi [Division of Cellular and Molecular Biology, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan)] [Division of Cellular and Molecular Biology, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan); Yamaguchi, Noritaka [Division of Cellular and Molecular Biology, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan) [Division of Cellular and Molecular Biology, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan); Consolidated Research Institute for Advanced Science and Medical Care, Waseda University, 513 Wasedatsurumaki-cho, Shinjuku-ku, Tokyo 162-0041 (Japan); Gohda, Jin [Division of Cellular and Molecular Biology, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan)] [Division of Cellular and Molecular Biology, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan); Semba, Kentaro [Consolidated Research Institute for Advanced Science and Medical Care, Waseda University, 513 Wasedatsurumaki-cho, Shinjuku-ku, Tokyo 162-0041 (Japan) [Consolidated Research Institute for Advanced Science and Medical Care, Waseda University, 513 Wasedatsurumaki-cho, Shinjuku-ku, Tokyo 162-0041 (Japan); Department of Life Science and Medical Bio-science, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480 (Japan); Inoue, Jun-ichiro, E-mail: jun-i@ims.u-tokyo.ac.jp [Division of Cellular and Molecular Biology, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan)] [Division of Cellular and Molecular Biology, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan)

    2009-10-09

    Pancreatic cancer has one of the poorest prognoses among human neoplasms. Constitutive activation of NF-{kappa}B is frequently observed in pancreatic cancer cells and is involved in their malignancy. However, little is known about the molecular mechanism of this constitutive NF-{kappa}B activation. Here, we show that the alternative pathway is constitutively activated and NF-{kappa}B-inducing kinase (NIK), a mediator of the alternative pathway, is significantly expressed in pancreatic cancer cells. siRNA-mediated silencing of NIK expression followed by subcellular fractionation revealed that NIK is constitutively involved in the processing of p100 and nuclear transport of p52 and RelB in pancreatic cancer cells. In addition, NIK silencing significantly suppressed proliferation of pancreatic cancer cells. These results clearly indicate that NIK is involved in the constitutive activation of the alternative pathway and controls cell proliferation in pancreatic cancer cells. Therefore, NIK might be a novel target for the treatment of pancreatic cancer.

  14. Cortical gamma activity during auditory tone omission provides evidence for the involvement of oscillatory activity in top-down processing

    Microsoft Academic Search

    I. G. Gurtubay; M. Alegre; M. Valencia; J. Artieda

    2006-01-01

    Perception is an active process in which our brains use top-down influences to modulate afferent information. To determine whether this modulation might be based on oscillatory activity, we asked seven subjects to detect a silence that appeared randomly in a rhythmic auditory sequence, counting the number of omissions (“count” task), or responding to each omission with a right index finger

  15. Phospholipase A{sub 2} is involved in the mechanism of activation of neutrophils by polychlorinated biphenyls

    SciTech Connect

    Tithof, P.K.; Schiamberg, E.; Ganey, P.E. [Univ. of Michigan, Ann Arbor, MI (United States); Peters-Golden, M. [Michigan State Univ., East Lansing, MI (United States)

    1996-01-01

    Aroclor 1242, a mixture of polychlorinated biphenyls (PCBs), activates neutrophils to produce superoxide anion (O{sub 2}{sup {minus}}) by a mechanism that involves phospholipase C-dependent hydrolysis of membrane phosphoinositides; however, subsequent signal transduction mechanisms are unknown. This study determines whether phospholipase A{sub 2}-dependent release of arachidonic acid is involved in PCB-induced O{sub 2}{sup {minus}} production. O{sub 2}{sup {minus}} production was measured in vitro in glycogen-elicited, rat neutrophils in the presence and absence of the inhibitors of phospholipase A{sub 2}: quinacrine, 4-bromophenacyl bromide (BPB), and manoalide. All three agents significantly decreased the amount of O{sub 2}{sup {minus}} detected during stimulation of neutrophils with Aroclor 1242. Similar inhibition occurred when neutrophils were activated with the classical stimuli, formyl-methionyl-leucyl-phenylalanine (fMLP) or phorbol myristate acetate. The effects of BPB and manoalide were not a result of cytotoxicity or other nonspecific effects. Significant release of {sup 3}H-arachidonic acid preceded O{sub 2}{sup {minus}} production in neutrophils stimulated with Aroclor 1242 or fMLP. Manoalide, at a concentration that abolished O{sub 2}{sup {minus}} production, also inhibited the release of {sup 3}H-arachidonate. Aspirin, zileuton, or WEB 2086 did not affect Aroclor 1242-induced O{sub 2}{sup {minus}} production, suggesting that eicosanoids and platelet-activating factor are not needed for neutrophil activation by PCBs. Activation of phos-pholipase A{sub 2} and O{sub 2}{sup {minus}} production do not appear to involve the Ah receptor. These data suggest that Aroclor 1242 stimulates neutrophils to produce O{sub 2}{sup {minus}} by a mechanism that involves phospholipase A{sub 2}-dependent release of arachiodonic acid. 49 refs., 6 figs., 2 tabs.

  16. S-nitrosohaemoglobin: a dynamic activity of blood involved in vascular control

    Microsoft Academic Search

    Li Jia; Celia Bonaventura; Joseph Bonaventura; Jonathan S. Stamler

    1996-01-01

    A dynamic cycle exists in which haemoglobin is S-nitrosylated in the lung when red blood cells are oxygenated, and the NO group is released during arterial-venous transit. The vasoactivity of S-nitrosohaemoglobin is promoted by the erythrocytic export of S-nitrosothiols. These findings highlight newly discovered allosteric and electronic properties of haemoglobin that appear to be involved in the control of blood

  17. Rundown of the hyperpolarization-activated KAT1 channel involves slowing of the opening transitions regulated by phosphorylation.

    PubMed Central

    Tang, X D; Hoshi, T

    1999-01-01

    Disappearance of the functional activity or rundown of ion channels upon patch excision in many cells involves a decrease in the number of channels available to open. A variety of cellular and biophysical mechanisms have been shown to be involved in the rundown of different ion channels. We examined the rundown process of the plant hyperpolarization-activated KAT1 K+ channel expressed in Xenopus oocytes. The decrease in the KAT1 channel activity on patch excision was accompanied by progressive slowing of the activation time course, and it was caused by a shift in the voltage dependence of the channel without any change in the single-channel amplitude. The single-channel analysis showed that patch excision alters only the transitions leading up to the burst states of the channel. Patch cramming or concurrent application of protein kinase A (PKA) and ATP restored the channel activity. In contrast, nonspecific alkaline phosphatase (ALP) accelerated the rundown time course. Low internal pH, which inhibits ALP activity, slowed the KAT1 rundown time course. The results show that the opening transitions of the KAT1 channel are enhanced not only by hyperpolarization but also by PKA-mediated phosphorylation. PMID:10354434

  18. B cell activation involves nanoscale receptor reorganizations and inside-out signaling by Syk

    PubMed Central

    Kläsener, Kathrin; Maity, Palash C; Hobeika, Elias; Yang, Jianying; Reth, Michael

    2014-01-01

    Binding of antigen to the B cell antigen receptor (BCR) initiates a multitude of events resulting in B cell activation. How the BCR becomes signaling-competent upon antigen binding is still a matter of controversy. Using a high-resolution proximity ligation assay (PLA) to monitor the conformation of the BCR and its interactions with co-receptors at a 10–20 nm resolution, we provide direct evidence for the opening of BCR dimers during B cell activation. We also show that upon binding Syk opens the receptor by an inside-out signaling mechanism that amplifies BCR signaling. Furthermore, we found that on resting B cells, the coreceptor CD19 is in close proximity with the IgD-BCR and on activated B cells with the IgM-BCR, indicating nanoscale reorganization of receptor clusters during B cell activation. DOI: http://dx.doi.org/10.7554/eLife.02069.001 PMID:24963139

  19. Directory of DOE and contractor personnel involved in non-government standards activities

    SciTech Connect

    NONE

    1995-08-01

    This document contains a listing of DOE employees and DOE contractors who have submitted form DOE F 1300.2, Record of Non-Government Standards Activity. Additional names were added from rosters supplied by non-Government standards bodies.

  20. Regulatory mechanisms involved in the activation of bradykinin-induced membrane currents in PC12 cells

    Microsoft Academic Search

    Alexandre Bouron; Harald Reuter

    1995-01-01

    Whole-cell patch-clamp measurements were made in nerve-growth-factor (NGF)-treated PC12 cells. External application of bradykinin (BK) activated an outward and an inward current which could be separated by using KCl- or CsCl-containing pipette solutions. The slowly activating inward current could be induced by BK independently of the filling of intracellular Ca2+ stores. By using GDP-?-S in the pipette medium, we showed

  1. Activation of the IL1?-Processing Inflammasome Is Involved in Contact Hypersensitivity

    Microsoft Academic Search

    Hideki Watanabe; Olivier Gaide; Virginie Pétrilli; Fabio Martinon; Emmanuel Contassot; Stéphanie Roques; Jean A Kummer; Jürg Tschopp; Lars E French

    2007-01-01

    The inflammasome is a cytosolic protein complex regulating the activation of caspase-1, which cleaves the pro-inflammatory cytokines IL-1? and IL-18 into their active form. The inflammasome is composed of a NACHT-, LRR- and pyrin (NALP) family member that acts as a sensor for danger signals and the adaptor protein apoptosis-associated speck-like protein containing a CARD domain (ASC), which allows the

  2. Selective Localization of Arc mRNA in Dendrites Involves Activity- and Translation-Dependent mRNA Degradation

    PubMed Central

    Farris, Shannon; Lewandowski, Gail; Cox, Conor D.

    2014-01-01

    Arc is an immediate early gene that is unique among neuronal mRNAs because its transcripts are transported into dendrites and accumulate near activated synapses, presumably to be translated locally. These qualities pose Arc as playing an important, yet not fully understood, role in the activity-dependent modifications of synapses that are thought to underlie memory storage. Here we show in vivo in rats that newly synthesized Arc mRNA accumulates at activated synapses and that synaptic activity simultaneously triggers mRNA decay that eliminates Arc mRNA from inactive dendritic domains. Arc mRNA degradation occurs throughout the dendrite and requires both NMDA receptor activation and active translation. Synaptic activation did not lead to decreases in another dendritic mRNA (?CaMKII), indicating that there is not a general activation of mRNA degradation in dendrites. These data reveal a novel mechanism for controlling mRNA distribution within dendrites and highlight activity-dependent mRNA degradation as a regulatory process involved in synaptic plasticity. PMID:24671994

  3. p53 transactivation is involved in the antiproliferative activity of the putative tumor suppressor RBM5.

    PubMed

    Kobayashi, Takahiko; Ishida, Junich; Musashi, Manabu; Ota, Shuichi; Yoshida, Takeshi; Shimizu, Yuichi; Chuma, Makoto; Kawakami, Hiroshi; Asaka, Masahiro; Tanaka, Junji; Imamura, Masahiro; Kobayashi, Masanobu; Itoh, Hiroshi; Edamatsu, Hironori; Sutherland, Leslie C; Brachmann, Rainer K

    2011-01-15

    RBM5 (RNA-binding motif protein 5) is a nuclear RNA binding protein containing 2 RNA recognition motifs. The RBM5 gene is located at the tumor suppressor locus 3p21.3. Deletion of this locus is the most frequent genetic alteration in lung cancer, but is also found in other human cancers. RBM5 is known to induce apoptosis and cell cycle arrest but the molecular mechanisms of RBM5 function are poorly understood. Here, we show that RBM5 is important for the activity of the tumor suppressor protein p53. Overexpression of RBM5 enhanced p53-mediated inhibition of cell growth and colony formation. Expression of RBM5 augmented p53 transcriptional activity in reporter gene assays and resulted in increased mRNA and protein levels for endogenous p53 target genes. In contrast, shRNA-mediated knockdown of endogenous RBM5 led to decreased p53 transcriptional activity and reduced levels of mRNA and protein for endogenous p53 target genes. RBM5 affected protein, but not mRNA, levels of endogenous p53 after DNA damage suggest that RBM5 contributes to p53 activity through post-transcriptional mechanisms. Our results show that RBM5 contributes to p53 transcriptional activity after DNA damage and that growth suppression and apoptosis mediated by RBM5 are linked to activity of the tumor suppressor protein p53. PMID:20309933

  4. Mechanosensitive channels are activated by stress in the actin stress fibres, and could be involved in gravity sensing in plants.

    PubMed

    Tatsumi, H; Furuichi, T; Nakano, M; Toyota, M; Hayakawa, K; Sokabe, M; Iida, H

    2014-01-01

    Mechanosensitive (MS) channels are expressed in a variety of cells. The molecular and biophysical mechanism involved in the regulation of MS channel activities is a central interest in basic biology. MS channels are thought to play crucial roles in gravity sensing in plant cells. To date, two mechanisms have been proposed for MS channel activation. One is that tension development in the lipid bilayer directly activates MS channels. The second mechanism proposes that the cytoskeleton is involved in the channel activation, because MS channel activities are modulated by pharmacological treatments that affect the cytoskeleton. We tested whether tension in the cytoskeleton activates MS channels. Mammalian endothelial cells were microinjected with phalloidin-conjugated beads, which bound to stress fibres, and a traction force to the actin cytoskeleton was applied by dragging the beads with optical tweezers. MS channels were activated when the force was applied, demonstrating that a sub-pN force to the actin filaments activates a single MS channel. Plants may use a similar molecular mechanism in gravity sensing, since the cytoplasmic Ca(2+) concentration increase induced by changes in the gravity vector was attenuated by potential MS channel inhibitors, and by actin-disrupting drugs. These results support the idea that the tension increase in actin filaments by gravity-dependent sedimentation of amyloplasts activates MS Ca(2+) -permeable channels, which can be the molecular mechanism of a Ca(2+) concentration increase through gravistimulation. We review recent progress in the study of tension sensing by actin filaments and MS channels using advanced biophysical methods, and discuss their possible roles in gravisensing. PMID:24016318

  5. Anticonvulsant activity of Citrus aurantium blossom essential oil (neroli): involvment of the GABAergic system.

    PubMed

    Azanchi, Taravat; Shafaroodi, Hamed; Asgarpanah, Jinous

    2014-11-01

    Citrus aurantium L. blossoms are an important medicinal plant part in Iran and some other countries. It is used in traditional medicine as an antiseizure and anticonvulsant natural agent. Early in vitro research of the anticonvulsant activity of the blossom extracts were done but there has been no investigation focused on the blossom essential oil and its anticonvulsant activity. The anticonvulsant activity of the essential oil of C. aurantium blossoms (neroli) was investigated. The anticonvulsant activity of neroli was assessed in pentylenetetrazole (PTZ)-induced convulsion by i.v. and i.p. methods and maximal electroshock (MES) in mice, with diazepam as the standard drug. While mechanistic studies were conducted using flumazenil, a GABA A-benzodiazepine receptor complex site antagonist. Neroli produced protection against clonic by i.v adminiatration of PTZ at 20 and 40 mg/kg, compared with protection with benzodiazepine. The mean onset and percentage protection against convulsion in neroli-treated mice were reduced by flumazenil. Intraperitonaeal PTZ also decreased the latency of clonic seizure in the neroli (40 mg/kg) treated group. We also showed that neroli (20 and 40 mg/kg), exhibited inhibition of the tonic convulsion induced by MES and decreased the mortality rate. Neroli was analyzed by GC and GC-MS and twenty three constituents, representing 91.0 % of the chromatographical oil were identified. The major components of neroli were characterized as linalool (28.5%), linalyl acetate (19.6%), nerolidol (9.1%) E,E-farnesol (9.1%), ?-terpineol (4.9%) and limonene (4.6%) which might be responsible for the anticonvulsant activity. The results suggest that neroli possesses biologically active constituent(s) that have anticonvulsant activity which supports the ethnomedicinal claims of the use of the plant in the management of seizure. PMID:25532295

  6. Factors Involved in Iranian Women Heads of Household’s Health Promotion Activities: A Grounded Theory Study

    PubMed Central

    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. PMID:24039645

  7. Oncogene activation in human benign tumors of the skin (keratoacanthomas): Is HRAS involved in differentiation as well as proliferation

    SciTech Connect

    Corominas, M.; Kamino, Hideko; Leon, J.; Pellicer, A. (New York Univ. Medical Center, New York, NY (USA))

    1989-08-01

    In vitro DNA amplification followed by oligonucleotide mismatch hybridization was used to study the frequency of HRAS mutations in the benign self-regressing skin tumors keratoacanthomas and in squamous cell carcinomas. The authors used freshly obtained keratoacanthomas as well as Formalin-fixed paraffin-embedded tissues from both types of tumors. DNA from 50 samples of each tumor type was analyzed for activating mutations involving codons 12 and 61. A relatively high percentage (30%) of HRAS mutations was found in the keratoacanthomas compared with 13% in the squamous cell carcinomas. The most frequent mutation identified is the A{center dot}T-to-T{center dot}A transversion in the second position of codon 61. The present findings demonstrate the involvement of the HRAS oncogene in human benign tumors. Moreover, they indicate that an activated HRAS oncogene is not sufficient to maintain a neoplastic phenotype and argue against a role of HRAS in the progression of skin tumorigenesis.

  8. Identification of signal transduction pathways involved in the formation of platelet subpopulations upon activation.

    PubMed

    Topalov, Nikolai N; Kotova, Yana N; Vasil'ev, Sergey A; Panteleev, Mikhail A

    2012-04-01

    Platelets are formed elements of blood. Upon activation, they externalize phosphatidylserine, thus accelerating membrane-dependent reactions of blood coagulation. Activated platelets form two subpopulations, only one of which expresses phosphatidylserine. This study aimed to identify signalling pathways responsible for this segregation. Gel-filtered platelets, intact or loaded with calcium-sensitive dyes, were activated and labelled with annexin V and antibodies, followed by flow cytometric analysis. Calcium Green and Fura Red dyes were compared, and only the latter was able to detect calcium level differences in the platelet subpopulations. Phosphatidylserine-positive platelets produced by thrombin had stably high intracellular calcium level; addition of convulxin increased and stabilized calcium level in the phosphatidylserine-negative subpopulation. PAR1 agonist SFLLRN also induced calcium rise and subpopulation formation, but the resulting platelets were not coated with alpha-granule proteins. Adenylatecyclase activator forskolin inhibited phosphatidylserine-positive platelets formation several-fold, while its inhibitor SQ22536 had no effect. This suggests that adenylatecyclase inactivation is necessary, but not rate-limiting, for subpopulation segregation. Inhibition of mitogen-activated protein kinase kinase (U0126) and glycoprotein IIb-IIIa (Monafram(®)) was without effect, whereas inhibitors of phosphatidylinositol 3-kinase (wortmannin) and Src tyrosine kinase (PP2) decreased the procoagulant subpopulation threefold. These data identify the principal signalling pathways controlling platelet heterogeneity. PMID:23379894

  9. Involvement of human internal globus pallidus in the early modulation of cortical error-related activity.

    PubMed

    Herrojo Ruiz, María; Huebl, Julius; Schönecker, Thomas; Kupsch, Andreas; Yarrow, Kielan; Krauss, Joachim K; Schneider, Gerd-Helge; Kühn, Andrea A

    2014-06-01

    The detection and assessment of errors are a prerequisite to adapt behavior and improve future performance. Error monitoring is afforded by the interplay between cortical and subcortical neural systems. Ample evidence has pointed to a specific cortical error-related evoked potential, the error-related negativity (ERN), during the detection and evaluation of response errors. Recent models of reinforcement learning implicate the basal ganglia (BG) in early error detection following the learning of stimulus-response associations and in the modulation of the cortical ERN. To investigate the influence of the human BG motor output activity on the cortical ERN during response errors, we recorded local field potentials from the sensorimotor area of the internal globus pallidus and scalp electroencephalogram representing activity from the posterior medial frontal cortex in patients with idiopathic dystonia (hands not affected) during a flanker task. In error trials, a specific pallidal error-related potential arose 60 ms prior to the cortical ERN. The error-related changes in pallidal activity-characterized by theta oscillations-were predictive of the cortical error-related activity as assessed by Granger causality analysis. Our findings show an early modulation of error-related activity in the human pallidum, suggesting that pallidal output influences the cortex at an early stage of error detection. PMID:23349222

  10. Activation of eNOS in endothelial cells exposed to ionizing radiation involves components of the DNA damage response pathway.

    PubMed

    Nagane, Masaki; Yasui, Hironobu; Sakai, Yuri; Yamamori, Tohru; Niwa, Koichi; Hattori, Yuichi; Kondo, Takashi; Inanami, Osamu

    2015-01-01

    In this study, the involvement of ataxia telangiectasia mutated (ATM) kinase and heat shock protein 90 (HSP90) in endothelial nitric oxide synthase (eNOS) activation was investigated in X-irradiated bovine aortic endothelial cells. The activity of nitric oxide synthase (NOS) and the phosphorylation of serine 1179 of eNOS (eNOS-Ser1179) were significantly increased in irradiated cells. The radiation-induced increases in NOS activity and eNOS-Ser1179 phosphorylation levels were significantly reduced by treatment with either an ATM inhibitor (Ku-60019) or an HSP90 inhibitor (geldanamycin). Geldanamycin was furthermore found to suppress the radiation-induced phosphorylation of ATM-Ser1181. Our results indicate that the radiation-induced eNOS activation in bovine aortic endothelial cells is regulated by ATM and HSP90. PMID:25498542

  11. The use of parent involved take-home science activities during student teaching: Understanding the challenges of implementation

    Microsoft Academic Search

    Jill Zarazinski

    2010-01-01

    The purpose of this study was to identify student teachers use and implementation of Science in a Bag when it was no longer a required course-based assessment. This take-home science activity acted as the elaboration component of the 5Es lesson teacher candidates designed and taught in the classroom, utilized household items, and directly involved parents in their child's education. The

  12. Differential involvement of excitatory and inhibitory neurons of cat motor cortex in coincident spike activity related to behavioral context.

    PubMed

    Putrino, David; Brown, Emery N; Mastaglia, Frank L; Ghosh, Soumya

    2010-06-01

    To assess temporal associations in spike activity between pairs of neurons in the primary motor cortex (MI) related to different behaviors, we compared the incidence of coincident spiking activity of task-related (TR) and non-task-related (NTR) neurons during a skilled motor task and sitting quietly in adult cats (Felis domestica). Chronically implanted microwires were used to record spike activity of MI neurons in four animals (two male and two female) trained to perform a skilled reaching task or sit quietly. Neurons were identified as TR if spike activity was modulated during the task (and NTR if not). Based on spike characteristics, they were also classified as either regular-spiking (RS, putatively excitatory) or fast-spiking (FS, putatively inhibitory) neurons. Temporal associations in the activities of simultaneously recorded neurons were evaluated using shuffle-corrected cross-correlograms. Pairs of NTR and TR neurons showed associations in their firing patterns over wide areas of MI (representing forelimb and hindlimb movements) during quiet sitting, more commonly involving RS neurons. During skilled task performance, however, significantly coincident firing was seen almost exclusively between TR neurons in a smaller part of MI (representing forelimb movements), involving mainly FS neurons. The findings of this study show evidence for widespread interactions in MI when the animal sits quietly, which changes to a more specific and restricted pattern of interactions during task performance. Different populations of excitatory and inhibitory neurons appear to be synchronized during skilled movement and quiet sitting. PMID:20534853

  13. Regulatory mechanisms involved in the activation of bradykinin-induced membrane currents in PC12 cells.

    PubMed

    Bouron, A; Reuter, H

    1995-07-28

    Whole-cell patch-clamp measurements were made in nerve-growth-factor (NGF)-treated PC12 cells. External application of bradykinin (BK) activated an outward and an inward current which could be separated by using KCl- or CsCl-containing pipette solutions. The slowly activating inward current could be induced by BK independently of the filling of intracellular Ca2+ stores. By using GDP-beta-S in the pipette medium, we showed that BK-induced outward and inward currents were differentially regulated through G-protein-sensitive and -insensitive mechanisms, respectively. While the outward current was inhibited by GDP-beta-S, the inward current was not affected. Our results show that occupancy of BK receptors activates different signaling pathways for the induction of outward and inward currents. PMID:7478249

  14. Parent-adolescent joint projects involving leisure time and activities during the transition to high school.

    PubMed

    Marshall, Sheila K; Young, Richard A; Wozniak, Agnieszka; Lollis, Susan; Tilton-Weaver, Lauree; Nelson, Margo; Goessling, Kristen

    2014-10-01

    Leisure research to date has generally overlooked planning and organizing of leisure time and activities between parents and adolescents. This investigation examined how a sample of Canadian adolescents and their parents jointly constructed and acted on goals related to adolescents' leisure time during the move from elementary to high school. Using the Qualitative Action-Project Method, data were collected over an 8-10 month period from 26 parent-adolescent dyads located in two urban sites, through video-taped conversations about leisure time, video recall interviews, and telephone monitoring interviews. Analysis of the data revealed that the joint projects of the 26 dyads could be grouped into three clusters: a) governance transfer or attempts to shift, from parent to adolescent, responsibility over academic demands, organizing leisure time, and safety with peers, b) balancing extra-curricular activities with family life, academics, and social activities, and c) relationship adjustment or maintenance. PMID:25134071

  15. Altered Renal FGF23-Mediated Activity Involving MAPK and Wnt: Effects of the Hyp Mutation

    PubMed Central

    Farrow, Emily G.; Summers, Lelia J.; Schiavi, Susan C.; McCormick, James A.; Ellison, David H.; White, Kenneth E.

    2011-01-01

    Fibroblast growth factor-23 (FGF23), a hormone central to renal phosphate handling, is elevated in multiple hypophosphatemic disorders. Initial FGF23-dependent Erk1/2 activity in the kidney localizes to the distal convoluted tubule (DCT) with the co-receptor ?-Klotho (KL), distinct from Npt2a in proximal tubules (PT). The Hyp mouse model of XLH is characterized by hypophosphatemia with increased Fgf23, and patients with XLH elevate FGF23 following combination therapy of phosphate and calcitriol. The molecular signaling underlying renal FGF23 activity, and whether these pathways are altered in hypophosphatemic disorders, is unknown. To examine Npt2a in vivo, mice were injected with FGF23. Initial p-Erk1/2 activity in the DCT occurred within 10 min, however Npt2a protein was latently reduced in the PT at 30–60 min, and was independent of Npt2a mRNA changes. KL-null mice had no DCT p-Erk1/2 staining following FGF23 delivery. Under basal conditions in Hyp mice, c-Fos and Egr1, markers of renal Fgf23 activity, were increased, however KL mRNA was reduced 60% (P<0.05). Despite the prevailing hypophosphatemia and elevated Fgf23, FGF23 injections into Hyp mice activated p-Erk1/2 in the DCT. FGF23 injection also resulted in phospho-?-catenin (p-?-cat) co-localization with KL in WT mice, and Hyp demonstrated strong p-?-cat staining under basal conditions, indicating potential cross-talk between Mapk and Wnt signaling. Collectively, these studies refine the mechanisms for FGF23 bioactivity, and demonstrate novel suppression of Wnt signaling in a KL-dependent DCT-PT axis, which is likely altered in XLH. Finally, the current treatment of phosphate and calcitriol for hypophosphatemic disorders may increase FGF23 activity. PMID:20675303

  16. Involvement of a membrane potassium channel in heparan sulphate-induced activation of macrophages

    PubMed Central

    Ren, Jian-Dong; Fan, Li; Tian, Fu-Zhou; Fan, Kai-Hua; Yu, Bo-Tao; Jin, Wei-Hua; Tan, Yong-Hong; Cheng, Long

    2014-01-01

    Increasing evidence has demonstrated that Toll-like receptor 4 (TLR4) -mediated systemic inflammatory response syndrome accompanied by multiple organ failure, is one of the most common causes of death in patients with severe acute pancreatitis. Recent reports have revealed that heparan sulphate (HS) proteoglycan, a component of extracellular matrices, potentiates the activation of intracellular pro-inflammatory responses via TLR4, contributing to the aggravation of acute pancreatitis. However, little is known about the participants in the HS/TLR4-mediated inflammatory cascades. Our previous work provided a clue that a membrane potassium channel (MaxiK) is responsible for HS-induced production of inflammatory cytokines. Therefore, in this report we attempted to reveal the roles of MaxiK in the activation of macrophages stimulated by HS. Our results showed that incubation of RAW264.7 cells with HS up-regulated MaxiK and TLR4 expression levels. HS could also activate MaxiK channels to promote the efflux of potassium ions from cells, as measured by the elevated activity of caspase-1, whereas this was significantly abolished by treatment with paxilline, a specific blocker of the MaxiK channel. Moreover, it was found that paxilline substantially inhibited HS-induced activation of several different transcription factors in macrophages, including nuclear factor-?B, p38 and interferon regulatory factor-3, followed by decreased production of tumour necrosis factor-? and interferon-?. Taken together, our investigation provides evidence that the HS/TLR4-mediated intracellular inflammatory cascade depends on the activation of MaxiK, which may offer an important opportunity for a new approach in therapeutic strategies of severe acute pancreatitis. PMID:24138091

  17. Complement activation is involved in the hepatic injury caused by high-dose exposure of mice to perfluorooctanoic acid.

    PubMed

    Botelho, Salomé Calado; Saghafian, Maryam; Pavlova, Svetlana; Hassan, Moustapha; DePierre, Joseph W; Abedi-Valugerdi, Manuchehr

    2014-08-01

    High-dose exposure of mice to perfluorooctanoate (PFOA) induces both hepatotoxicity and immunotoxicity. Here, we characterized the effects of 10-day dietary treatment with PFOA (0.002-0.02%, w/w) on the liver and complement system of male C57BL/6 mice. At all four doses, this compound caused hepatomegaly and reduced the serum level of triglycerides (an indicator for activation of the peroxisome proliferator-activated receptor-alpha (PPAR?)). At the highest dose (0.02%, w/w), this hepatomegaly was associated with the hepatic injury, as reflected in increased activity of alanine aminotranferase (ALAT) in the serum, severe hepatocyte hypertrophy and hepatocellular necrosis. PFOA-induced hepatic injury was associated with in vivo activation of the complement system as indicated by (i) significant attenuation of the serum activities of both the classical and alternative pathways; (ii) a marked reduction in the serum level of the complement factor C3; and (iii) deposition of the complement factor C3 fragment (C3a) in the hepatic parenchyma. PFOA did not activate the alternative pathway of complement in vitro. At doses lower than 0.02%, PFOA induced hepatocyte hypertrophy without causing liver injury or activating complement. These results reveal substantial involvement of activation of complement in the pathogenesis of PFOA-induced hepatotoxicity. PMID:25108893

  18. Serotonergic involvement in methamphetamine-induced locomotor activity: A detailed pharmacological study

    Microsoft Academic Search

    Emily Steed; Caitlin A. Jones; Andrew C. McCreary

    2011-01-01

    The mechanism by which the psychostimulant methamphetamine (METH) increases locomotor activity may be attributable to indirect activation of serotonin (5-HT) and dopamine (DA) receptors. In the present study, the ability of the serotonin reuptake inhibitor fluvoxamine, 5-HT1A, 5-HT1B, 5-HT2A and 5-HT2C receptor antagonists WAY100635, GR127935, M100907 and SB242084, and the 5-HT2C receptor agonists WAY163909 and Ro 60-0175 or the 5-HT

  19. ?3 subunit of Na,K ATPase regulates T cell activation with no involvement of Na,K ATPase activity.

    PubMed

    Chruewkamlow, Nuttapol; Pata, Supansa; Mahasongkram, Kodchakorn; Laopajon, Witida; Kasinrerk, Watchara; Chiampanichayakul, Sawitree

    2015-05-01

    Na,K ATPase plays an important role in the regulation of Na(+) and K(+) ions that are required for normal resting membrane potential and various cellular functions. Na,K ATPase is composed of two subunits, ? and ? subunits. Engagement of the ? subunit by an agonistic monoclonal antibody (mAb) P-3E10 inhibited T cell activation and induced the G0/G1 cell cycle arrest. In addition, mAb P-3E10 decreased CD25 expression. The mAb P-3E10, however, did not inhibit the proliferation of cell lines and the phagocytosis activity of phagocytes, and did not interfere with the Na,K ATPase activity. These results indicate that mAb P-3E10 reacts to the ? subunit and, as a consequence, brings about the regulation of the T cell activation without disturbing the Na,K pump activity. By sequential immunoprecipitation, we demonstrated the expression of the ?3 subunit free form apart from the ? subunit. In this study, we propose that the ?3 subunits of Na,K ATPase are expressed separately from the ? subunit, and play a role in regulation of the immune response. PMID:25678464

  20. Involvement of sensor kinase gene (skrp 1122) for biocontrol activity by Pseudomonas synxantha BG33R

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Previous research identified Pseudomonas synxantha BG33R as potential carrier for a nematode egg-kill factor. Further research indicated that BG33R exhibits a broad-spectrum of antagonistic activity against oomycetes, fungi, nematodes and insects. Earlier screening for negative egg-kill factor indi...

  1. School-Based Extracurricular Activity Involvement and Adolescent Self-Esteem: A Growth-Curve Analysis

    ERIC Educational Resources Information Center

    Kort-Butler, Lisa A.; Hagewen, Kellie J.

    2011-01-01

    Research on adolescent self-esteem indicates that adolescence is a time in which individuals experience important changes in their physical, cognitive, and social identities. Prior research suggests that there is a positive relationship between an adolescent's participation in structured extracurricular activities and well-being in a variety of…

  2. Marketing Informal Education Institutions in Israel: The Centrality of Customers' Active Involvement in Service Development

    ERIC Educational Resources Information Center

    Oplatka, Izhar

    2004-01-01

    The current paper outlines a unique marketing perspective that prevails in some informal education institutions in Israel parallel with "traditional modes of marketing", such as promotion, public relations and the like. Based on a case study research in five community centres, a service development based on active participation of the potential…

  3. Physical Activity Based Professional Development for Teachers: The Importance of Whole School Involvement

    ERIC Educational Resources Information Center

    Till, Jude; Ferkins, Lesley; Handcock, Phil

    2011-01-01

    Objective: This study sought to investigate teachers' perceptions of a physical activity-related professional development intervention. Design: Interview-based qualitative approach founded on the interpretive paradigm. Setting: Purposive selection of one high-rated independent, and one low-rated public primary school from Auckland, New Zealand.…

  4. Hypnosis Modulates Activity in Brain Structures Involved in the Regulation of Consciousness

    Microsoft Academic Search

    Pierre Rainville; Robert K. Hofbauer; M. Catherine Bushnell; Gary H. Duncan; Donald D. Price

    2002-01-01

    The notion of consciousness is at the core of an ongoing debate on the existence and nature of hypnotic states. Previously, we have described changes in brain activity associated with hypnosis (Rainville, Hofbauer, Paus, Duncan, Bushnell, & Price, 1999). Here, we replicate and extend those findings using positron emission tomography (PET) in 10 normal volunteers. Immediately after each of 8

  5. Bonsaï, a ribosomal protein S15 homolog, involved in gut mitochondrial activity and systemic growth.

    PubMed

    Galloni, Mireille

    2003-12-15

    The regulation of cellular growth is crucial in the control of cell proliferation. While most of the metabolic energy necessary to sustain growth is produced in mitochondria, the regulation of mitochondrial activity and its implications for growth have remained unexplored. Here, a gene named bonsaï is described, which is essential for normal growth in Drosophila. The Bonsaï protein bears strong homology to prokaryotic ribosomal protein S15 and localizes to mitochondria, suggesting a role in mitochondrial protein translation. Accordingly, bonsaï mutants have defective mitochondrial activity, but surprisingly, only the gut appears affected. Consistent with these observations, bonsaï is predominantly expressed in the gut. These results show that bonsaï plays a preponderant role in gut mitochondria. Although gut mitochondrial respiration is altered in bonsaï mutants, the digestive process appears normal, suggesting that a gut function other than digestion is impaired in the mutants. Cytochrome c oxidase, a respiratory chain enzyme partly encoded by the mitochondrial genome, is found to be active in bonsaï mutants. This suggests that mitochondrial translation is not abolished in the mutants. Altogether, these observations suggest that mitochondrial activity is regulated at the tissue-specific level and that this regulation has profound implications for growth and development. PMID:14651932

  6. Effect of Parent Involvement in Classroom Activities on Parents' and Children's Attitude toward School.

    ERIC Educational Resources Information Center

    Moulin, Nelly

    A study was conducted to determine: (1) the extent to which the Alternative Pre-School Program (APSP) affected Brazilian parents' and children's attitudes toward school; and (2) the extent to which parents encouraged children to repeat at home the skill development activities they experienced at school. The program, which provided educational…

  7. Mechanism of activation of methyltransferases involved in translation by the Trm112 'hub' protein.

    PubMed

    Liger, Dominique; Mora, Liliana; Lazar, Noureddine; Figaro, Sabine; Henri, Julien; Scrima, Nathalie; Buckingham, Richard H; van Tilbeurgh, Herman; Heurgué-Hamard, Valérie; Graille, Marc

    2011-08-01

    Methylation is a common modification encountered in DNA, RNA and proteins. It plays a central role in gene expression, protein function and mRNA translation. Prokaryotic and eukaryotic class I translation termination factors are methylated on the glutamine of the essential and universally conserved GGQ motif, in line with an important cellular role. In eukaryotes, this modification is performed by the Mtq2-Trm112 holoenzyme. Trm112 activates not only the Mtq2 catalytic subunit but also two other tRNA methyltransferases (Trm9 and Trm11). To understand the molecular mechanisms underlying methyltransferase activation by Trm112, we have determined the 3D structure of the Mtq2-Trm112 complex and mapped its active site. Using site-directed mutagenesis and in vivo functional experiments, we show that this structure can also serve as a model for the Trm9-Trm112 complex, supporting our hypothesis that Trm112 uses a common strategy to activate these three methyltransferases. PMID:21478168

  8. Mechanism of activation of methyltransferases involved in translation by the Trm112 ‘hub’ protein

    PubMed Central

    Liger, Dominique; Mora, Liliana; Lazar, Noureddine; Figaro, Sabine; Henri, Julien; Scrima, Nathalie; Buckingham, Richard H.; van Tilbeurgh, Herman; Heurgué-Hamard, Valérie; Graille, Marc

    2011-01-01

    Methylation is a common modification encountered in DNA, RNA and proteins. It plays a central role in gene expression, protein function and mRNA translation. Prokaryotic and eukaryotic class I translation termination factors are methylated on the glutamine of the essential and universally conserved GGQ motif, in line with an important cellular role. In eukaryotes, this modification is performed by the Mtq2-Trm112 holoenzyme. Trm112 activates not only the Mtq2 catalytic subunit but also two other tRNA methyltransferases (Trm9 and Trm11). To understand the molecular mechanisms underlying methyltransferase activation by Trm112, we have determined the 3D structure of the Mtq2-Trm112 complex and mapped its active site. Using site-directed mutagenesis and in vivo functional experiments, we show that this structure can also serve as a model for the Trm9-Trm112 complex, supporting our hypothesis that Trm112 uses a common strategy to activate these three methyltransferases. PMID:21478168

  9. Involvement of semenogelin-derived peptides in the antibacterial activity of human seminal plasma.

    PubMed

    Bourgeon, Frédéric; Evrard, Bertrand; Brillard-Bourdet, Michèle; Colleu, Daniel; Jégou, Bernard; Pineau, Charles

    2004-03-01

    Mechanisms for protecting spermatozoa, and the testes that produce them, from infection are essential, given the importance of these cells and organs for the fertility of the individual and perpetuation of the species. This is borne out by the publication of numerous papers on this subject over the last 50 years. We extended our work and that of others on the anti-infectious defense system of the male genital tract, using a new strategy for the direct identification of antibacterial molecules in human seminal plasma. We subjected a liquefied seminal plasma cationic fraction to reversed-phase HPLC, monitored microbicidal activity by gel overlay and radial diffusion assays, and identified the proteins and/or peptides present in each active fraction by mass spectrometry. In addition to proteins with known potent microbicidal activity--phospholipase A2, lactoferrin, and lysozyme--we also found that peptides produced by cleavage of semenogelin I, the predominant human semen coagulum protein, had high levels of antibacterial activity. PMID:14613901

  10. How Curriculum Leaders Can Involve the Right Brain in Active Reading and Writing Development.

    ERIC Educational Resources Information Center

    Sinatra, Richard; Stahl-Gemake, Josephine

    Curriculum leaders, program specialists, and teachers can intentionally arouse the activation of one hemisphere of the brain over the other through the use of right brain strategies in language learning. While most functions of the left hemisphere are concerned with convergent production (getting the right answer), functions of the right…

  11. GBA2-Encoded ?-Glucosidase Activity Is Involved in the Inflammatory Response to Pseudomonas aeruginosa

    PubMed Central

    Lampronti, Ilaria; Marchetti, Nicola; Aureli, Massimo; Bassi, Rosaria; Giri, Maria Grazia; Bezzerri, Valentino; Lovato, Valentina; Cantù, Cinzia; Munari, Silvia; Cheng, Seng H.; Cavazzini, Alberto; Gambari, Roberto; Sonnino, Sandro; Cabrini, Giulio; Dechecchi, Maria Cristina

    2014-01-01

    Current anti-inflammatory strategies for the treatment of pulmonary disease in cystic fibrosis (CF) are limited; thus, there is continued interest in identifying additional molecular targets for therapeutic intervention. Given the emerging role of sphingolipids (SLs) in various respiratory disorders, including CF, drugs that selectively target the enzymes associated with SL metabolism are under development. Miglustat, a well-characterized iminosugar-based inhibitor of ?-glucosidase 2 (GBA2), has shown promise in CF treatment because it reduces the inflammatory response to infection by P. aeruginosa and restores F508del-CFTR chloride channel activity. This study aimed to probe the molecular basis for the anti-inflammatory activity of miglustat by examining specifically the role of GBA2 following the infection of CF bronchial epithelial cells by P. aeruginosa. We also report the anti-inflammatory activity of another potent inhibitor of GBA2 activity, namely N-(5-adamantane-1-yl-methoxy)pentyl)-deoxynojirimycin (Genz-529648). In CF bronchial cells, inhibition of GBA2 by miglustat or Genz-529648 significantly reduced the induction of IL-8 mRNA levels and protein release following infection by P. aeruginosa. Hence, the present data demonstrate that the anti-inflammatory effects of miglustat and Genz-529648 are likely exerted through inhibition of GBA2. PMID:25141135

  12. Families and School Personnel Involved in a Literacy and Physical Activity Partnership

    ERIC Educational Resources Information Center

    Richardson, James A.; Richardson, Maurine V.; Sacks, Mary Kathleen

    2006-01-01

    A traditional part of American education has been to include the families in the educational process of their children. The needs and complexities of today's families and classrooms have never been greater. Programs and activities used with families, and school interactions 10 to 15 years ago are not effective for today's complex families and…

  13. Cultural Variation in Young Children's Opportunities for Involvement in Adult Activities.

    ERIC Educational Resources Information Center

    Morelli, Gilda A.; And Others

    This study gathered information on the extent to which children participate in the mature routines of their community, and the extent to which elders participate in child-centered activities. Subjects were children ranging in age from 30 to 45 months from the four societies of: (1) Mayan Indians living in a rural Guatemalan town; (2) the Efe…

  14. Involvement of HAb18G/CD147 in T cell activation and immunological synapse formation

    PubMed Central

    Hu, Jinsong; Dang, Nana; Yao, Hui; Li, Yu; Zhang, Hongxin; Yang, Xiangmin; Xu, Jing; Bian, Huijie; Xing, Jinliang; Zhu, Ping; Chen, Zhinan

    2010-01-01

    Abstract HAb18G/CD147, a glycoprotein of the immunoglobulin super-family (IgSF), is a T cell activation-associated molecule. In this report, we demonstrated that HAb18G/CD147 expression on both activated CD4+ and CD8+ T cells was up-regulated. In vitro cross-linking of T cells with an anti-HAb18G/CD147 monoclonal antibody (mAb) 5A12 inhibited T cells proliferation upon T cell receptor stimulation. Such co-stimulation inhibited T cell proliferation by down-regulating the expression of CD25 and interleukin-2 (IL-2), decreased production of IL-4 but not interferon-?. Laser confocal imaging analysis indicated that HAb18G/CD147 was recruited to the immunological synapse (IS) during T cell activation; triggering HAb18G/CD147 on activated T cells by anti-HAb18G/CD147 mAb 5A12 strongly dispersed the formation of the IS. Further functional studies showed that the ligation of HAb18G/CD147 with mAb 5A12 decreased the tyrosine phosphorylation and intracellular calcium mobilization levels of T cells. Through docking antibody–antigen interactions, we demonstrated that the function of mAb 5A12 is tightly dependent on its specificity of binding to N-terminal domain I, which plays pivotal role in the oligomerization of HAb18G/CD147. Taken together, we provide evidence that HAb18G/CD147 could act as a co-stimulatory receptor to negatively regulate T cell activation and is functionally linked to the formation of the IS. PMID:20082657

  15. 5?-AMP Activated Protein Kinase is Involved in the Regulation of Myocardial ?-Oxidative Capacity in Mice

    PubMed Central

    Stride, Nis; Larsen, Steen; Treebak, Jonas Thue; Hansen, Christina Neigaard; Hey-Mogensen, Martin; Speerschneider, Tobias; Jensen, Thomas E.; Jeppesen, Jacob; Wojtaszewski, Jørgen F. P.; Richter, Erik A.; Køber, Lars; Dela, Flemming

    2012-01-01

    5?-adenosine monophosphate-activated protein kinase (AMPK) is considered central in regulation of energy status and substrate utilization within cells. In heart failure the energetic state is compromised and substrate metabolism is altered. We hypothesized that this could be linked to changes in AMPK activity and we therefore investigated mitochondrial oxidative phosphorylation capacity from the oxidation of long- and medium-chain fatty acids (LCFA and MCFA) in cardiomyocytes from young and old mice expressing a dominant negative AMPK?2 (AMPK?2-KD) construct and their wildtype (WT) littermates. We found a 35–45% (P?activity (14/21%, P?activity or progressing age. Expression of regulatory proteins of glycolysis and glycogen breakdown showed equivocal effects of age and genotype. These results illustrate that AMPK is necessary for normal mitochondrial function in the heart and that decreased AMPK activity may lead to an altered energetic state as a consequence of reduced capacity to oxidize MCFA. We did not identify any clear aging effects on mitochondrial function. PMID:22371704

  16. Antiulcer activity of Muntingia calabura leaves involves the modulation of endogenous nitric oxide and nonprotein sulfhydryl compounds.

    PubMed

    Balan, Tavamani; Mohd Sani, Mohd Hijaz; Suppaiah, Velan; Mohtarrudin, Norhafizah; Suhaili, Zarizal; Ahmad, Zuraini; Zakaria, Zainul Amiruddin

    2013-11-01

    Abstract Context: Muntingia calabura L. (Muntingiaceae) is a native plant species of the American continent and is widely cultivated in warm areas in Asia, including Malaysia. The plant is traditionally used to relieve pain from gastric ulcers. Objective: This study was designed to determine the antiulcer activity of a methanol extract of M. calabura leaves (MEMC) and the possible mechanisms of action involved. Materials and methods: An acute toxicity study was conducted using a single oral dose of 2000?mg/kg MEMC. The antiulcer activity of MEMC was evaluated in absolute ethanol- and indomethacin-induced gastric ulcer rat models. MEMC was administered orally (dose range 25-500?mg/kg) to rats fasted for 24?h. The animals were pretreated with N(G)-nitro-l-arginine methyl esters (l-NAME) or N-ethylmaleimide (NEM) prior to MEMC treatment to assess the possible involvement of endogenous nitric oxide (NO) and nonprotein sulfhydryl (NP-SH) compounds in the gastroprotective effect of MEMC. Results: As the administered dose did not cause toxicity in the rats, the oral median lethal dose (LD50) of MEMC was >2000?mg/kg in rats. MEMC exerted significant (p?activity in the ethanol- and indomethacin-induced ulcer models dose-dependently. Histological evaluation supported the observed antiulcer activity of MEMC. l-NAME and NEM pretreatment significantly (p?activity that might involve the participation of endogenous NO and NP-SH compounds. These findings provide new pharmacological information regarding the potential use of M. calabura. PMID:24192248

  17. Dopamine receptor-mediated mechanisms involved in the expression of learned activity of primate striatal neurons.

    PubMed

    Watanabe, K; Kimura, M

    1998-05-01

    To understand the mechanisms by which basal ganglia neurons express acquired activities during and after behavioral learning, selective dopamine (DA) receptor antagonists were applied while recording the activity of striatal neurons in monkeys performing behavioral tasks. In experiment 1, a monkey was trained to associate a click sound with a drop of reward water. DA receptor antagonists were administered by micropressure using a stainless steel injection cannula (300 microm ID) through which a Teflon-coated tungsten wire for recording neuronal activity had been threaded. Responses to sound by tonically active neurons (TANs), a class of neurons in the primate striatum, were recorded through a tungsten wire electrode during the application of either D1- or D2-class DA receptor antagonists (total volume <1 microl, at a rate of 1 microl/5-10 min). Application of the D2-class antagonist, (-)-sulpiride (20 micrograms/microl, 58 mM, pH 6.8), abolished the responses of four of five TANs examined. In another five TANs, neither the D2-class antagonist nor the D1-class antagonists, SCH23390 (10 micrograms/microl, 31 mM, pH 5.7) or cis-flupenthixol (30 micrograms/microl, 59 mM, pH 6.6) significantly suppressed responses. In experiment 2, four- or five-barreled glass microelectrodes were inserted into the striatum. The central barrel was used for extracellular recording of activity of TANs. Each DA receptor antagonist was iontophoretically applied through one of the surrounding barrels. SCH23390 (10 mM, pH 4.5) and (-)-sulpiride (10 mM, pH 4.5) were used. The effects of iontophoresis of both D1- and D2-class antagonists were examined in 40 TANs. Of 40 TANs from which recordings were made, responses were suppressed exclusively by the D2-class antagonist in 19 TANs, exclusively by the D1-class antagonist in 3 TANs, and by both D1- and D2-class antagonists in 7 TANs. When 0.9% NaCl, saline, was applied by pressure (<1 microl) or by iontophoresis (<30 nA) as a control, neither the background discharge rates nor the responses of TANs were significantly influenced. Background discharge rate of TANs was also not affected by D1- or D2-class antagonists applied by either micropressure injection or iontophoresis. It was concluded that the nigrostriatal DA system enables TANs to express learned activity primarily through D2-class and partly through D1-class receptor-mediated mechanisms in the striatum. PMID:9582229

  18. Designing active flutter suppression for high-dimensional aeroelastic systems involving a control delay

    NASA Astrophysics Data System (ADS)

    Huang, Rui; Hu, Haiyan; Zhao, Yonghui

    2012-10-01

    Many linear control laws, such as optimal controllers and classical controllers, have seen their applications to suppressing the aeroelastic vibrations of the high-dimensional aeroelastic system. However, those conventional control laws may not work effectively if the high-dimensional aeroelastic system involves a control delay. The paper reveals the effect of input time delay on the stability of a controlled high-dimensional aeroelastic system in an incompressible flow field and presents a new optimal control law to suppress the flutter of the high-dimensional aeroelastic system with an input time delay in the control loop. The procedure of designing the proposed control law includes three steps as follows. The first step is to convert the system described by a set of differential equations with a time delay into a set of difference equations involving discrete delay terms by using zero-order holder. The second step, exhibiting the novelty of the study, is to transform the difference equations with delay terms into a set of delay-free difference equations via a state transformation. The third step is to use the theory of linear control, say, the theory of Linear Quadratic Gaussian (LQG), to complete the design of controller by solving an equivalent Riccati equation. The paper demonstrates the efficacy of proposed method in designing the flutter suppression controller for a wind-tunnel model of Multiple-Actuated Wing. The new method works much better than classical feedback and conventional LQG controllers, both of which do not take the input time delay into account and may induce instability, when the input time delay becomes significant.

  19. AMP-activated protein kinase (AMPK)-induced preconditioning in primary cortical neurons involves activation of MCL-1.

    PubMed

    Anilkumar, Ujval; Weisová, Petronela; Düssmann, Heiko; Concannon, Caoimhín G; König, Hans-Georg; Prehn, Jochen H M

    2013-03-01

    Neuronal preconditioning is a phenomenon where a previous exposure to a sub-lethal stress stimulus increases the resistance of neurons towards a second, normally lethal stress stimulus. Activation of the energy stress sensor, AMP-activated protein kinase (AMPK) has been shown to contribute to the protective effects of ischaemic and mitochondrial uncoupling-induced preconditioning in neurons, however, the molecular basis of AMPK-mediated preconditioning has been less well characterized. We investigated the effect of AMPK preconditioning using 5-aminoimidazole-4-carboxamide riboside (AICAR) in a model of NMDA-mediated excitotoxic injury in primary mouse cortical neurons. Activation of AMPK with low concentrations of AICAR (0.1 mM for 2 h) induced a transient increase in AMPK phosphorylation, protecting neurons against NMDA-induced excitotoxicity. Analysing potential targets of AMPK activation, demonstrated a marked increase in mRNA expression and protein levels of the anti-apoptotic BCL-2 family protein myeloid cell leukaemia sequence 1 (MCL-1) in AICAR-preconditioned neurons. Interestingly, over-expression of MCL-1 protected neurons against NMDA-induced excitotoxicity while MCL-1 gene silencing abolished the effect of AICAR preconditioning. Monitored intracellular Ca²? levels during NMDA excitation revealed that MCL-1 over-expressing neurons exhibited improved bioenergetics and markedly reduced Ca²? elevations, suggesting a potential mechanism through which MCL-1 confers neuroprotection. This study identifies MCL-1 as a key effector of AMPK-induced preconditioning in neurons. PMID:23199202

  20. Activism and Leadership Development: Examining the Relationship between College Student Activism Involvement and Socially Responsible Leadership Capacity

    ERIC Educational Resources Information Center

    Page, Jeremy Dale

    2010-01-01

    The purpose of this study was to examine the relationship between participation in student activism and leadership development among college students. This study applied the social change model of leadership development (SCM) as the theoretical model used to measure socially responsible leadership capacity in students. The study utilized data…

  1. Cytoplasmic enzyme activities involved in energy and amino acid metabolism in pathological human renal cortex.

    PubMed

    González-Buitrago, J M; Corrales, J J; Pastor, I

    1988-12-01

    Enzyme levels of lactate dehydrogenase (LDH), alpha-hydroxybutyrate dehydrogenase (HBDH), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were measured in the cytosol of renal cortex samples from either normal and pathologic kidney tissue. The mean enzyme activity values, expressed in Units per gram of cytosolic protein decreased in the following order: normal cortex (LDH = 4,299 +/- 654; AST = 522 +/- 101; ALT = 197 +/- 44). chronic pyelonephritis (LDH = 2,360 +/- 876; AST = 297 +/- 117; ALT = 90 +/- 48), hydronephrosis (LDH = 2,208 +/- 1,264; AST = 279 +/- 165; ALT = 82 +/- 61), pyonephrosis (LDH = 1,410 +/- 596; AST = 158 +/- 69; ALT = 23.4 +/- 16.4) and renal tuberculosis (LDH = 1,149 +/- 481; AST = 93 +/- 34; ALT = 5.6 +/- 2.8). The decrease in the enzyme activities paralleled tissue damage and it was shown to affect cellular functionality in relation with energy and amino acid metabolism. PMID:3244890

  2. Involvement of ASK1 activation in apoptosis induced by NPe6-PDT

    NASA Astrophysics Data System (ADS)

    Liu, Lei; Zhang, Zhen-zhen; Zhang, Zhigang

    2010-02-01

    Photodynamic therapy (PDT) employing photosensiter N-aspartyl chlorin e6 (NPe6) can induce lysosome disruption and initiate apoptotic pathway. Apoptosis signal-regulating kinase (ASK1) is an important regulator of apoptosis in response to various stresses, such as reactive oxygen species (ROS), endoplasmic reticulum (ER) stress, lipopolysaccharide (LPS) and calcium influx. In this study, we investigated the molecular mechanisms of apoptosis induced by NPe6-PDT in ASTC-a-1 cells. The results showed that the activities of ASK1 increased in response to NPe6-PDT. Over-expression of wild-type or activated mutant of ASK1 could obviously decrease cell viability and increase cell death; while inhibition of ASK1 significantly decreased cell apoptosis. These results suggested that ASK1 plays an important role in apoptosis induced by NPe6-PDT.

  3. Killing of staphylococci by ?-defensins involves membrane impairment and activation of autolytic enzymes

    PubMed Central

    Wilmes, Miriam; Stockem, Marina; Bierbaum, Gabriele; Schlag, Martin; Götz, Friedrich; Tran, Dat Q.; Schaal, Justin B.; Ouellette, André J.; Selsted, Michael E.; Sahl, Hans-Georg

    2015-01-01

    ?-Defensins are cyclic antimicrobial peptides expressed in leukocytes of Old world monkeys. To get insight into their antibacterial mode of action, we studied the activity of RTDs (rhesus macaque ?-defensins) against staphylococci. We found that in contrast to other defensins, RTDs do not interfere with peptidoglycan biosynthesis, but rather induce bacterial lysis in staphylococci by interaction with the bacterial membrane and/or release of cell wall lytic enzymes. Potassium efflux experiments and membrane potential measurements revealed that the membrane impairment by RTDs strongly depends on the energization of the membrane. In addition, RTD treatment caused the release of Atl-derived cell wall lytic enzymes probably by interaction with membrane-bound lipoteichoic acid. Thus, the premature and uncontrolled activity of these enzymes contributes strongly to the overall killing by ?-defensins. Interestingly, a similar mode of action has been described for Pep5, an antimicrobial peptide of bacterial origin. PMID:25632351

  4. Ncb2 Is Involved in Activated Transcription of CDR1 in Azole-Resistant Clinical Isolates of Candida albicans?†

    PubMed Central

    Shukla, Shipra; Yadav, Vipin; Mukhopadhyay, Gauranga; Prasad, Rajendra

    2011-01-01

    We recently demonstrated that CDR1 overexpression in azole-resistant isolates of Candida albicans is due to its enhanced transcriptional activation and increased mRNA stability. In this study, we provide the first evidence of transcriptional regulation of CDR1 by Ncb2, the ? subunit of NC2, a heterodimeric regulator of transcription. Conditional NCB2 null mutants displayed decreased susceptibility toward azole and an enhanced transcription of CDR1. Interestingly, Ncb2 associated with the CDR1 promoter under both repression and activation; however, an increase in recruitment was observed under both transient and constitutive activation states. By chromatin immunoprecipitation (ChIP) assay, we showed the preferential recruitment of Ncb2 to the core TATA region under activation (azole-resistant isolate), while under repression (azole-susceptible isolate) it was present at the TATA upstream region. Further, ChIP analysis revealed that Ncb2 binding was not restricted to the CDR1 gene; instead, it was observed on the promoters of genes coregulated with CDR1 by the transcription activator Tac1. The tac1? null mutants, which fail to show the drug-induced transient activation of CDR1, also showed no increase in Ncb2 recruitment at the promoter. Taken together, our results show that Ncb2, in conjunction with Tac1, is involved in the transcriptional activation of CDR1, opening up new therapeutic possibilities to combat multidrug resistance (MDR) in C. albicans. PMID:21856931

  5. Alleviation of Eco K DNA restriction in Escherichia coli and involvement of umuDC activity

    Microsoft Academic Search

    Kevin J. Hiom; Steven G. Sedgwick

    1992-01-01

    The activity of the EcoK DNA restriction system of Escherichia coli reduces both the plating efficiency of unmodified phage ? and the transforming ability of unmodified pBR322 plasmid DNA. However, restriction can be alleviated in wild-type cells, by UV irradiation and expression of the SOS response, so that 103-to 104-fold increases in phage growth and fourfold increases in plasmid transformation

  6. Heat shock elements are involved in heat shock promoter activation during tobacco seed maturation

    Microsoft Academic Search

    Ralf Prändl; Fritz Schöffl

    1996-01-01

    The soybean Gmhsp17.3-B heat shock promoter is developmentally regulated in transgenic tobacco, as indicated by the constitutive expression of a ß-glucuronidase reporter in seeds [16]. In this paper, we show that both the heat shock promoter-driven ß-glucuronidase activity and the mRNA of the endogenous Nthsp18P gene accumulate coincident with the onset of seed desiccation. Deletions of the soybean Gmhsp17.3-B promoter,

  7. Novel DNA mismatch repair activity involving YB-1 in human mitochondria

    PubMed Central

    de Souza-Pinto, Nadja C.; Mason, Penelope A.; Hashiguchi, Kazunari; Weissman, Lior; Tian, Jingyan; Guay, David; Lebel, Michel; Stevnsner, Tinna V.; Rasmussen, Lene Juel; Bohr, Vilhelm A.

    2009-01-01

    Maintenance of the mitochondrial genome (mtDNA) is essential for proper cellular function. The accumulation of damage and mutations in the mtDNA leads to diseases, cancer, and aging. Mammalian mitochondria have proficient base excision repair, but the existence of other DNA repair pathways is still unclear. Deficiencies in DNA mismatch repair (MMR), which corrects base mismatches and small loops, are associated with DNA microsatellite instability, accumulation of mutations, and cancer. MMR proteins have been identified in yeast and coral mitochondria; however, MMR proteins and function have not yet been detected in human mitochondria. Here we show that human mitochondria have a robust mismatch-repair activity, which is distinct from nuclear MMR. Key nuclear MMR factors were not detected in mitochondria, and similar mismatch-binding activity was observed in mitochondrial extracts from cells lacking MSH2, suggesting distinctive pathways for nuclear and mitochondrial MMR. We identified the repair factor YB-1 as a key candidate for a mitochondrial mismatch-binding protein. This protein localizes to mitochondria in human cells, and contributes significantly to the mismatch-binding and mismatch-repair activity detected in HeLa mitochondrial extracts, which are significantly decreased when the intracellular levels of YB-1 are diminished. Moreover, YB-1 depletion in cells increases mitochondrial DNA mutagenesis. Our results show that human mitochondria contain a functional MMR repair pathway in which YB-1 participates, likely in the mismatch binding and recognition steps. PMID:19272840

  8. UVA-mediated activation of signaling pathways involved in skin tumor promotion and progression.

    PubMed

    Bachelor, Michael A; Bowden, G Tim

    2004-04-01

    Each year more than 1,000,000 cases of non-melanoma skin cancer (NMSC) are diagnosed in the Unites States. Solar radiation has been described as an important etiological factor in the development of NMSC. UVA comprises the largest portion of solar radiation reaching the surface of the earth (90-99%) and has been described to lead to benign tumor formation as well as malignant cancers, squamous cell carcinomas (SCCs). While much research has focused upon the effects of UVB radiation, little is known about UVA-induced signaling pathways and their role in tumor promotion. Here we focus on UVA-mediated activation of mitogen-activated protein kinase (MAPK) pathways and their role in activator protein-1 (AP-1) mediated transcription and cyclooxygenase-2 (COX-2) expression. AP-1 and COX-2 have been found to play a role in angiogenesis in other tissues. We propose UVA-mediated increases in AP-1 and COX-2 may play a role in tumor promotion through increases in interleukin-8 (IL-8) and vascular endothelial growth factor (VEGF). Since MAPKs, specifically p38 and JNK, appear to play a major role in the expression of UVA-induced AP-1 and COX-2, pharmacological inhibitors may be of benefit in the chemoprevention of non-melanoma skin cancer. PMID:15018897

  9. GABAergic Neural Activity Involved in Salicylate-Induced Auditory Cortex Gain Enhancement

    PubMed Central

    Lu, Jianzhong; Lobarinas, Edward; Deng, Anchun; Goodey, Ronald; Stolzberg, Daniel; Salvi, Richard J.; Sun, Wei

    2011-01-01

    Although high doses of sodium salicylate impair cochlear function, it paradoxically enhances sound-evoked activity in the auditory cortex (AC) and augments acoustic startle reflex responses, neural and behavioral metrics associated with hyperexcitability and hyperacusis. To explore the neural mechanisms underlying salicylate-induced hyperexcitability and “increased central gain”, we examined the effects of ?-aminobutyric acid (GABA) receptor agonists and antagonists on salicylate-induced hyperexcitability in the AC and startle reflex responses. Consistent with our previous findings, local or systemic application of salicylate significantly increased the amplitude of sound-evoked AC neural activity, but generally reduced spontaneous activity in the AC. Systemic injection of salicylate also significantly increased the acoustic startle reflex. S-baclofen or R-baclofen, GABA-B agonists, which suppressed sound-evoked AC neural firing rate and local field potentials, also suppressed the salicylate-induced enhancement of the AC field potential and the acoustic startle reflex. Local application of vigabatrin, which enhances GABA concentration in the brain, suppressed the salicylate-induced enhancement of AC firing rate. Systemic injection of vigabatrin also reduced the salicylate-induced enhancement of acoustic startle reflex. Collectively, these results suggest that the sound-evoked behavioral and neural hyperactivity induced by salicylate may arise from a salicylate-induced suppression GABAergic inhibition in the AC. PMID:21664433

  10. Amidase activity involved in peptidoglycan biosynthesis in membranes of Micrococcus luteus (sodonensis).

    PubMed Central

    Jensen, S E; Campbell, J N

    1976-01-01

    Membrane suspensions prepared from Micrococcus luteus (sodonensis) in both the exponential and stationary phases of growth contained a transglycosidase activity capable of synthesizing linear peptidoglycan. Exponential-phase membranes also contained an N-acetylmuramyl-L-alanine amidase activity which degraded the peptidoglycan as it was formed. The product of this amidase was purified and found to be free pentapeptide. The amidase was specific for peptidoglycan and could not attack lower-molecular-weight substrates even though the susceptible bond was present. Crude cell wall preparations isolated from exponential-phase cells also contained high levels of amidase. This cell wall-bound amidase would preferentially degrade in vitro-synthesized peptidoglycan over its own cell wall. Amidase activity could be solubilized from both cell walls and membranes by Triton X-100 treatment, butanol extraction, or LiCl extraction. Both membrane- and cell wall-derived amidases, solubilized by LiCl extraction, appeared to be of high molecular weight (greater than 150,000). Once solubilized, these wall- and membrane-derived amidases could attack the cross-bridged peptidoglycan of purified native cell walls, whereas bound amidases could not. PMID:931948

  11. Intact long-type DupA protein in Helicobacter pylori is an ATPase involved in multifunctional biological activities.

    PubMed

    Wang, Ming-Yi; Chen, Cheng; Shao, Chen; Wang, Shao-Bo; Wang, Ai-Chu; Yang, Ya-Chao; Yuan, Xiao-Yan; Shao, Shi-He

    2015-04-01

    The function of intact long-type DupA protein in Helicobacter pylori was analyzed using immunoblotting and molecular biology techniques in the study. After cloning, expression and purification, ATPase activity of DupA protein was detected. Antibody was produced for localization and interaction proteins analysis. The dupA-deleted mutant was generated for adhesion and CagA protein translocation assay, susceptibility to different pH, IL-8 secretion assay, cytotoxicity to MKN-45 cells and proteins-involved apoptosis analysis. DupA protein exhibited an ATPase activity (129.5±17.8 U/mgprot) and located in bacterial membrane, while it did not involve the adhesion and CagA protein delivery of H. pylori. DupA protein involved the urease secretion as the interaction proteins. The wild type strain had a stronger growth in low pH than the dupA-deleted mutant (p < 0.001). IL-8 productions from GES-1 cells infected with the wild type strain were significantly higher than from those with the mutant (p < 0.001). The amounts of vital MKN-45 cells were decreased and the numbers of apoptotic cells were increased with the wild type strain, compared to those with the mutant after 12 h (p < 0.05). The increase of cleaved Caspase-3 and Bax was significantly higher and the decrease of Bcl-2 was more obvious in MKN-45 cells exposed to the wild type strain than that exposed to the mutant after 6 h. We demonstrate that intact long-type DupA protein located in membrane as ATPase is a true virulence factor associated with duodenal ulcer development involving the IL-8 induction and urease secretion, while it inhibits gastric cancer cell growth in vitro by activating the mitochondria-mediated apoptotic pathway. PMID:25745877

  12. Paxillin-dependent Paxillin Kinase Linker and p21-Activated Kinase Localization to Focal Adhesions Involves a Multistep Activation Pathway

    PubMed Central

    Brown, Michael C.; West, Kip A.; Turner, Christopher E.

    2002-01-01

    The precise temporal-spatial regulation of the p21-activated serine-threonine kinase PAK at the plasma membrane is required for proper cytoskeletal reorganization and cell motility. However, the mechanism by which PAK localizes to focal adhesions has not yet been elucidated. Indirect binding of PAK to the focal adhesion protein paxillin via the Arf-GAP protein paxillin kinase linker (PKL) and PIX/Cool suggested a mechanism. In this report, we demonstrate an essential role for a paxillin–PKL interaction in the recruitment of activated PAK to focal adhesions. Similar to PAK, expression of activated Cdc42 and Rac1, but not RhoA, stimulated the translocation of PKL from a generally diffuse localization to focal adhesions. Expression of the PAK regulatory domain (PAK1–329) or the autoinhibitory domain (AID 83–149) induced PKL, PIX, and PAK localization to focal adhesions, indicating a role for PAK scaffold activation. We show PIX, but not NCK, binding to PAK is necessary for efficient focal adhesion localization of PAK and PKL, consistent with a PAK–PIX–PKL linkage. Although PAK activation is required, it is not sufficient for localization. The PKL amino terminus, containing the PIX-binding site, but lacking paxillin-binding subdomain 2 (PBS2), was unable to localize to focal adhesions and also abrogated PAK localization. An identical result was obtained after PKL?PBS2 expression. Finally, neither PAK nor PKL was capable of localizing to focal adhesions in cells overexpressing paxillin?LD4, confirming a requirement for this motif in recruitment of the PAK–PIX–PKL complex to focal adhesions. These results suggest a GTP-Cdc42/GTP-Rac triggered multistep activation cascade leading to the stimulation of the adaptor function of PAK, which through interaction with PIX provokes a functional PKL PBS2–paxillin LD4 association and consequent recruitment to focal adhesions. This mechanism is probably critical for the correct subcellular positioning of PAK, thereby influencing the ability of PAK to coordinate cytoskeletal reorganization associated with changes in cell shape and motility. PMID:12006652

  13. Regulation of Human CYP2C9 Expression by Electrophilic Stress Involves Activator Protein 1 Activation and DNA Looping

    PubMed Central

    Makia, Ngome L.; Surapureddi, Sailesh; Monostory, Katalin; Prough, Russell A.

    2014-01-01

    Cytochrome P450 (CYP)2C9 and CYP2C19 are important human enzymes that metabolize therapeutic drugs, environmental chemicals, and physiologically important endogenous compounds. Initial studies using primary human hepatocytes showed induction of both the CYP2C9 and CYP2C19 genes by tert-butylhydroquinone (tBHQ). As a pro-oxidant, tBHQ regulates the expression of cytoprotective genes by activation of redox-sensing transcription factors, such as the nuclear factor E2-related factor 2 (Nrf2) and members of the activator protein 1 (AP-1) family of proteins. The promoter region of CYP2C9 contains two putative AP-1 sites (TGAGTCA) at positions ?2201 and ?1930, which are also highly conserved in CYP2C19. The CYP2C9 promoter is activated by ectopic expression of cFos and JunD, whereas Nrf2 had no effect. Using specific kinase inhibitors for mitogen-activated protein kinase, we showed that extracellular signal-regulated kinase and Jun N-terminal kinase are essential for tBHQ-induced expression of CYP2C9. Electrophoretic mobility shift assays demonstrate that cFos distinctly interacts with the distal AP-1 site and JunD with the proximal site. Because cFos regulates target genes as heterodimers with Jun proteins, we hypothesized that DNA looping might be required to bring the distal and proximal AP-1 sites together to activate the CYP2C9 promoter. Chromosome conformation capture analyses confirmed the formation of a DNA loop in the CYP2C9 promoter, possibly allowing interaction between cFos at the distal site and JunD at the proximal site to activate CYP2C9 transcription in response to electrophiles. These results indicate that oxidative stress generated by exposure to electrophilic xenobiotics and metabolites induces the expression of CYP2C9 and CYP2C19 in human hepatocytes. PMID:24830941

  14. DOE Technical Standards List. Directory of DOE and contractor personnel involved in non-government standards activities

    SciTech Connect

    NONE

    1997-06-01

    This is a periodic report on the level of agency participation in non-Government standards activities. This technical standards list is intended to assist US Department of Energy (DOE) management and other personnel involved in the DOE technical Standards Program by identifying those participating individuals. The body of this document contains a listing of DOE employees and DOE contractors who have submitted a Record of Non-Government Standards Activity. Additional names were added from rosters supplied by non-Government standards bodies. Appendices to this document are provided to list the information by parent employment organization, by non-Government standards activity, and by the proper names of the non-Government standards organizations and committees.

  15. Fnr Is Involved in Oxygen Control of Herbaspirillum seropedicae N-Truncated NifA Protein Activity in Escherichia coli

    PubMed Central

    Monteiro, Rose A.; de Souza, Emanuel M.; Yates, M. Geoffrey; Pedrosa, Fabio O.; Chubatsu, Leda S.

    2003-01-01

    Herbaspirillum seropedicae is an endophytic diazotroph belonging to the ?-subclass of the class Proteobacteria, which colonizes many members of the Gramineae. The activity of the NifA protein, a transcriptional activator of nif genes in H. seropedicae, is controlled by ammonium ions through its N-terminal domain and by oxygen through mechanisms that are not well understood. Here we report that the NifA protein of H. seropedicae is inactive and more susceptible to degradation in an fnr Escherichia coli background. Both effects correlate with oxygen exposure and iron deprivation. Our results suggest that the oxygen sensitivity and iron requirement for H. seropedicae NifA activity involve the Fnr protein. PMID:12620839

  16. Signal transducer and activator of transcription 3 is involved in the cardioprotective signalling pathway activated by insulin therapy at reperfusion

    PubMed Central

    Suleman, Naushaad; Tiron, Crina; Kanhema, Tambuzai; Lacerda, Lydia; Andreasen, Thomas V.; Sack, Michael N.; Jonassen, Anne K.; Mjøs, Ole D.; Opie, Lionel H.; Lecour, Sandrine

    2012-01-01

    Objective To evaluate the significance of the JAK-STAT pathway in insulin-induced cardioprotection from reperfusion injury. Methods In isolated perfused rat hearts subjected to insulin therapy (0.3 mU/ml) ± AG490 (5 ?M, JAK-STAT inhibitor), the phosphorylation state of STAT3 and Akt was determined after 15 min of reperfusion. Infarct size was measured after 120 min of reperfusion. Isolated cardiac myocytes from wild type (WT) and cardiac specific STAT3 deficient mice were treated with insulin at reoxygenation following simulated ischemia (SI, 26 h). Cell viability was measured after 120 min of reoxygenation following SI, whereas phosphorylation state of Akt was measured after 15 min of reoxygenation following SI. Results Insulin given at reperfusion led to phosphorylation of STAT3 and Akt both of which were inhibited by AG490. AG490 also blocked the insulin-dependent decrease in infarct size, supporting a role for JAK-STAT in cardioprotection. In addition, insulin protection from SI was blocked in myocytes from the STAT3 deficient mice, or in WT mice treated with AG490. Furthermore, insulin failed to phosphorylate Akt in the STAT3 deficient cardiomyocytes. Conclusion Insulin-induced cardioprotection at reperfusion occurs through activation of STAT3. Inhibiting STAT3 by AG490, or STAT3 depletion in cardiac myocytes affects activation of Akt, suggesting close interaction between STAT3 and Akt in the cardioprotective signalling pathway activated by insulin treatment at reperfusion. PMID:18500485

  17. Evidence that central 5-hydroxytryptaminergic neurones are involved in the anxiolytic activity of buspirone.

    PubMed Central

    Carli, M.; Prontera, C.; Samanin, R.

    1989-01-01

    1. A two-compartment exploratory test was used to assess the role of central 5-hydroxytryptaminergic neurones in the anxiolytic activity of buspirone in rats. 2. Buspirone 0.1 mg kg-1, administered subcutaneously 15 min before testing, significantly increased black-white transitions (BWT) in control rats but had no effect in animals injected intracerebroventricularly one week before with 150 micrograms 5,7-dihydroxytryptamine (in 20 microliters). 3. Infusion of buspirone in the median raphe (but not in the dorsal raphe) significantly enhanced BWT, at doses from 1 micrograms to 10 micrograms (in 0.5 microliters). Buspirone 5 and 10 micrograms, but not 1 microgram, administered in the median raphe, significantly enhanced motor activity of rats during the first 10 min of testing in the activity cages. 4. The effect on BWT of 5 micrograms buspirone in the median raphe was completely antagonized in animals which had received either 5,7-dihydroxytryptamine intraventricularly, 150 micrograms (in 20 microliters), one week before or an infusion of 0.1 microgram (in 0.5 microliter) (-)-propranolol in the same area 5 min before. (-)-Propranolol infused in the median raphe did not modify the effect of buspirone on locomotion. 5. Infusion of 5 micrograms buspirone (in 0.5 microliter) in the median raphe significantly enhanced punished responses in a conflict test with no effect on unpunished responding. Buspirone infused in the dorsal raphe had no effect on punished or unpunished responding over a wide dose range. 6. The results indicate that at the relatively low dose used in the present study buspirone produces an anxiolytic effect by acting on central 5-hydroxytryptaminergic neurones.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2568143

  18. The gastroprotective effect of menthol: involvement of anti-apoptotic, antioxidant and anti-inflammatory activities.

    PubMed

    Rozza, Ariane Leite; Meira de Faria, Felipe; Souza Brito, Alba Regina; Pellizzon, Cláudia Helena

    2014-01-01

    The aim of this research was to investigate the anti-apoptotic, antioxidant and anti-inflammatory properties of menthol against ethanol-induced gastric ulcers in rats. Wistar rats were orally treated with vehicle, carbenoxolone (100 mg/kg) or menthol (50 mg/kg) and then treated with ethanol to induce gastric ulcers. After euthanasia, stomach samples were prepared for histological slides and biochemical analyses. Immunohistochemical analyses of the cytoprotective and anti-apoptotic heat-shock protein-70 (HSP-70) and the apoptotic Bax protein were performed. The neutrophils were manually counted. The activity of the myeloperoxidase (MPO) was measured. To determine the level of antioxidant functions, the levels of glutathione (GSH), glutathione peroxidase (GSH-Px), glutathione reductase (GR) and superoxide dismutase (SOD) were measured using ELISA. The levels of the pro-inflammatory cytokines tumor necrosis factor-? (TNF-?) and interleukin-6 (IL-6) and the anti-inflammatory cytokine interleukin-10 (IL-10) were assessed using ELISA kits. The menthol treated group presented 92% gastroprotection compared to the vehicle-treated group. An increased immunolabeled area was observed for HSP-70, and a decreased immunolabeled area was observed for the Bax protein in the menthol treated group. Menthol treatment induced a decrease in the activity of MPO and SOD, and the protein levels of GSH, GSH-Px and GR were increased. There was also a decrease in the levels of TNF-? and IL-6 and an increase in the level of IL-10. In conclusion, oral treatment with menthol displayed a gastroprotective activity through anti-apoptotic, antixidant and anti-inflammatory mechanisms. PMID:24466200

  19. The Gastroprotective Effect of Menthol: Involvement of Anti-Apoptotic, Antioxidant and Anti-Inflammatory Activities

    PubMed Central

    Rozza, Ariane Leite; Meira de Faria, Felipe; Souza Brito, Alba Regina; Pellizzon, Cláudia Helena

    2014-01-01

    The aim of this research was to investigate the anti-apoptotic, antioxidant and anti-inflammatory properties of menthol against ethanol-induced gastric ulcers in rats. Wistar rats were orally treated with vehicle, carbenoxolone (100 mg/kg) or menthol (50 mg/kg) and then treated with ethanol to induce gastric ulcers. After euthanasia, stomach samples were prepared for histological slides and biochemical analyses. Immunohistochemical analyses of the cytoprotective and anti-apoptotic heat-shock protein-70 (HSP-70) and the apoptotic Bax protein were performed. The neutrophils were manually counted. The activity of the myeloperoxidase (MPO) was measured. To determine the level of antioxidant functions, the levels of glutathione (GSH), glutathione peroxidase (GSH-Px), glutathione reductase (GR) and superoxide dismutase (SOD) were measured using ELISA. The levels of the pro-inflammatory cytokines tumor necrosis factor-? (TNF-?) and interleukin-6 (IL-6) and the anti-inflammatory cytokine interleukin-10 (IL-10) were assessed using ELISA kits. The menthol treated group presented 92% gastroprotection compared to the vehicle-treated group. An increased immunolabeled area was observed for HSP-70, and a decreased immunolabeled area was observed for the Bax protein in the menthol treated group. Menthol treatment induced a decrease in the activity of MPO and SOD, and the protein levels of GSH, GSH-Px and GR were increased. There was also a decrease in the levels of TNF-? and IL-6 and an increase in the level of IL-10. In conclusion, oral treatment with menthol displayed a gastroprotective activity through anti-apoptotic, antixidant and anti-inflammatory mechanisms. PMID:24466200

  20. Spiroketal formation and modification in avermectin biosynthesis involves a dual activity of AveC.

    PubMed

    Sun, Peng; Zhao, Qunfei; Yu, Futao; Zhang, Hua; Wu, Zhuhua; Wang, Yinyan; Wang, Yan; Zhang, Qinglin; Liu, Wen

    2013-01-30

    Avermectins (AVEs), which are widely used for the treatment of agricultural parasitic diseases, belong to a family of 6,6-spiroketal moiety-containing, macrolide natural products. AVE biosynthesis is known to employ a type I polyketide synthase (PKS) system to assemble the molecular skeleton for further functionalization. It remains unknown how and when spiroketal formation proceeds, particularly regarding the role of AveC, a unique protein in the pathway that shares no sequence homology to any enzyme of known function. Here, we report the unprecedented, dual function of AveC by correlating its activity with spiroketal formation and modification during the AVE biosynthetic process. The findings in this study were supported by characterizing extremely unstable intermediates, products and their spontaneous derivative products from the simplified chemical profile and by comparative analysis of in vitro biotransformations and in vivo complementations mediated by AveC and MeiC (the counterpart in biosynthesizing the naturally occurring, AVE-like meilingmycins). AveC catalyzes the stereospecific spiroketalization of a dihydroxy-ketone polyketide intermediate and the optional dehydration to determine the regiospecific saturation characteristics of spiroketal diversity. These reactions take place between the closures of the hexene ring and 16-membered macrolide and the formation of the hexahydrobenzofuran unit. MeiC can replace the spirocyclase activity of AveC, but it lacks the independent dehydratase activity. Elucidation of the generality and specificity of AveC-type proteins allows for the rationalization of previously published results that were not completely understood, suggesting that enzyme-mediated spiroketal formation was initially underestimated, but is, in fact, widespread in nature for the control of stereoselectivity. PMID:23294008

  1. Menadione triggers cell death through ROS-dependent mechanisms involving PARP activation without requiring apoptosis

    PubMed Central

    Loor, Gabriel; Kondapalli, Jyothisri; Schriewer, Jacqueline M.; Chandel, Navdeep S.; Vanden Hoek, Terry L.; Schumacker, Paul T.

    2010-01-01

    Low levels of reactive oxygen species (ROS) can function as redox-active signaling messengers, whereas high levels of ROS induce cellular damage. Menadione generates ROS through redox cycling, and high concentrations trigger cell death. Previous work suggests that menadione triggers cytochrome c release from mitochondria, while other studies implicate activation of the mitochondrial permeability transition poreas the mediator of cell death. We investigated menadione-induced cell death in genetically modified cells lacking specific death-associated proteins. In cardiomyocytes, oxidant stress was assessed using the redox sensor RoGFP, expressed in the cytosol or the mitochondrial matrix. Menadione elicited rapid oxidation in both compartments, while it decreased mitochondrial potential and triggered cytochrome c redistribution to the cytosol. Cell death was attenuated by N-acetyl cysteine and exogenous glutathione (GSH), or by over-expression of cytosolic or mitochondria-targeted catalase. By contrast, no protection was observed in cells over-expressing Cu, Zn-SOD or MnSOD. Over-expression of antiapoptotic Bcl-XLprotected against staurosporine-induced cell death, but it failed to confer protection against menadione. Genetic deletion of Bax and Bak, cytochrome c, cyclophilin D or caspase-9 conferred no protection against menadione-induced cell death. However, cells lacking PARP-1 showed a significant decrease in menadione-induced cell death. Thus, menadione induces cell death through the generation of oxidant stress in multiple subcellular compartments, yet cytochromec, Bax/Bak, caspase-9 and cyclophilin D are dispensable for cell death in this model. These studies suggest that multiple redundant cell death pathways are activated by menadione, but that PARP plays an essential role in mediating each of them. PMID:20937380

  2. Pb-inhibited mitotic activity in onion roots involves DNA damage and disruption of oxidative metabolism.

    PubMed

    Kaur, Gurpreet; Singh, Harminder Pal; Batish, Daizy Rani; Kohli, Ravinder Kumar

    2014-09-01

    Plant responses to abiotic stress significantly affect the development of cells, tissues and organs. However, no studies correlating Pb-induced mitotic inhibition and DNA damage and the alterations in redox homeostasis during root division per se were found in the literature. Therefore, an experiment was conducted to evaluate the impact of Pb on mitotic activity and the associated changes in the oxidative metabolism in onion roots. The cytotoxic effect of Pb on cell division was assessed in the root meristems of Allium cepa (onion). The mitotic index (MI) was calculated and chromosomal abnormalities were sought. Pb-treatment induced a dose-dependent decrease in MI in the onion root tips and caused mitotic abnormalities such as distorted metaphase, fragments, sticky chromosomes, laggards, vagrant chromosomes and bridges. Single Cell Gel Electrophoresis was also performed to evaluate Pb induced genotoxicity. It was accompanied by altered oxidative metabolism in the onion root tips suggesting the interference of Pb with the redox homeostasis during cell division. There was a higher accumulation of malondialdehyde, conjugated dienes and hydrogen peroxide, and a significant increase in the activities of superoxide dismutases, ascorbate peroxidases, guaiacol peroxidases and glutathione reductases in Pb-treated onion roots, whereas catalases activity exhibited a decreasing pattern upon Pb exposure. The study concludes that Pb-induced cytotoxicity and genotoxicity in the onion roots is mediated through ROS and is also tightly linked to the cell cycle. The exposure to higher concentrations arrested cell cycle leading to cell death, whereas different repair responses are generated at lower concentrations, thereby allowing the cell to complete the cell cycle. PMID:25023386

  3. Sequential Polymicrobial Infections Lead to CNS Inflammatory Disease: Possible Involvement of Bystander Activation in Heterologous Immunity

    PubMed Central

    Tsunoda, Ikuo; Libbey, Jane E.; Fujinami, Robert S.

    2007-01-01

    VVPLP is a recombinant vaccinia virus (VV) encoding myelin proteolipid protein (PLP) that has been used to investigate molecular mimicry and autoimmunity. Since virus infections can cause bystander activation, mice were first infected with VVPLP, and later challenged with wild-type VV, lymphocytic choriomeningitis virus (LCMV), or murine cytomegalovirus (MCMV). Among the VVPLP-primed mice, only MCMV challenge induced significant Ki-67+, CD3+ T cell infiltration into the central nervous system (CNS) with a mild PLP antibody response. While MCMV alone caused no CNS disease, control VV-infected mice followed with MCMV developed mild CNS inflammation. Thus, heterologous virus infections can induce CNS pathology. PMID:17604850

  4. Involvement of CD14 and Toll-Like Receptors in Activation of Human Monocytes by Aspergillus fumigatus Hyphae

    PubMed Central

    Wang, J. E.; Warris, A.; Ellingsen, E. A.; Jørgensen, P. F.; Flo, T. H.; Espevik, T.; Solberg, R.; Verweij, P. E.; Aasen, A. O.

    2001-01-01

    Invasive fungal infections represent an increasing problem associated with high mortality. The present study was undertaken to identify leukocyte subsets that are activated by hyphal fragments in a whole-human-blood model, as well as to examine the involvement of CD14 and Toll-like receptors (TLRs) in activation of monocytes by hyphae. Incubation of whole human blood with hyphal fragments from Aspergillus fumigatus and Scedosporium prolificans for 6 h caused induction of mRNAs for tumor necrosis factor alpha (TNF-?), interleukin-1? (IL-1?), and IL-6 in T cells, B cells, and monocytes, but not in granulocytes, as analyzed by reverse transcription-PCR with mRNA isolated from very pure populations of these leukocyte subsets. In primary adherent human monocytes, induction of TNF-? by hyphal fragments was dependent on plasma. Heat treatment of plasma at 56°C for 30 min strongly reduced the ability of plasma to prime for activation. Pretreatment of human monocytes with different concentrations (1, 3, and 10 ?g/ml) of monoclonal antibody (MAb) HTA125 (anti-TLR4) or MAb 18D11 (anti-CD14) for 30 min inhibited the release of TNF-? induced by hyphal fragments in a dose-dependent manner. Maximal inhibitions of 35 and 70% were obtained with 10 ?g of HTA125 and 18D11 per ml, respectively. In contrast, pretreatment with MAb TL2.1 (anti-TLR2) did not affect signaling induced by hyphae. Pretreatment with the lipid A antagonist B975 blocked lipopolysaccharide signaling but did not inhibit TNF-? production induced by hyphal fragments. Our results suggest that T cells, B cells, and monocytes are involved in the innate immune response to invasive fungal pathogens and that serum components are relevant for activation of monocytes by hyphae. CD14 and TLR4 may be involved in signaling of Aspergillus hyphae in monocytes, but further studies to elucidate this issue are warranted. PMID:11254600

  5. PhosphoTyrosyl Phosphatase Activator of Plasmodium falciparum: Identification of Its Residues Involved in Binding to and Activation of PP2A

    PubMed Central

    Vandomme, Audrey; Fréville, Aline; Cailliau, Katia; Kalamou, Hadidjatou; Bodart, Jean-François; Khalife, Jamal; Pierrot, Christine

    2014-01-01

    In Plasmodium falciparum (Pf), the causative agent of the deadliest form of malaria, a tight regulation of phosphatase activity is crucial for the development of the parasite. In this study, we have identified and characterized PfPTPA homologous to PhosphoTyrosyl Phosphatase Activator, an activator of protein phosphatase 2A which is a major phosphatase involved in many biological processes in eukaryotic cells. The PfPTPA sequence analysis revealed that five out of six amino acids involved in interaction with PP2A in human are conserved in P. falciparum. Localization studies showed that PfPTPA and PfPP2A are present in the same compartment of blood stage parasites, suggesting a possible interaction of both proteins. In vitro binding and functional studies revealed that PfPTPA binds to and activates PP2A. Mutation studies showed that three residues (V283, G292 and M296) of PfPTPA are indispensable for the interaction and that the G292 residue is essential for its activity. In P. falciparum, genetic studies suggested the essentiality of PfPTPA for the completion of intraerythrocytic parasite lifecycle. Using Xenopus oocytes, we showed that PfPTPA blocked the G2/M transition. Taken together, our data suggest that PfPTPA could play a role in the regulation of the P. falciparum cell cycle through its PfPP2A regulatory activity. PMID:24521882

  6. PhosphoTyrosyl phosphatase activator of Plasmodium falciparum: identification of its residues involved in binding to and activation of PP2A.

    PubMed

    Vandomme, Audrey; Fréville, Aline; Cailliau, Katia; Kalamou, Hadidjatou; Bodart, Jean-François; Khalife, Jamal; Pierrot, Christine

    2014-01-01

    In Plasmodium falciparum (Pf), the causative agent of the deadliest form of malaria, a tight regulation of phosphatase activity is crucial for the development of the parasite. In this study, we have identified and characterized PfPTPA homologous to PhosphoTyrosyl Phosphatase Activator, an activator of protein phosphatase 2A which is a major phosphatase involved in many biological processes in eukaryotic cells. The PfPTPA sequence analysis revealed that five out of six amino acids involved in interaction with PP2A in human are conserved in P. falciparum. Localization studies showed that PfPTPA and PfPP2A are present in the same compartment of blood stage parasites, suggesting a possible interaction of both proteins. In vitro binding and functional studies revealed that PfPTPA binds to and activates PP2A. Mutation studies showed that three residues (V(283), G(292) and M(296)) of PfPTPA are indispensable for the interaction and that the G(292) residue is essential for its activity. In P. falciparum, genetic studies suggested the essentiality of PfPTPA for the completion of intraerythrocytic parasite lifecycle. Using Xenopus oocytes, we showed that PfPTPA blocked the G2/M transition. Taken together, our data suggest that PfPTPA could play a role in the regulation of the P. falciparum cell cycle through its PfPP2A regulatory activity. PMID:24521882

  7. Phage Orf Family Recombinases: Conservation of Activities and Involvement of the Central Channel in DNA Binding

    PubMed Central

    Curtis, Fiona A.; Malay, Ali D.; Trotter, Alexander J.; Wilson, Lindsay A.; Barradell-Black, Michael M. H.; Bowers, Laura Y.; Reed, Patricia; Hillyar, Christopher R. T.; Yeo, Robert P.; Sanderson, John M.; Heddle, Jonathan G.; Sharples, Gary J.

    2014-01-01

    Genetic and biochemical evidence suggests that ? Orf is a recombination mediator, promoting nucleation of either bacterial RecA or phage Red? recombinases onto single-stranded DNA (ssDNA) bound by SSB protein. We have identified a diverse family of Orf proteins that includes representatives implicated in DNA base flipping and those fused to an HNH endonuclease domain. To confirm a functional relationship with the Orf family, a distantly-related homolog, YbcN, from Escherichia coli cryptic prophage DLP12 was purified and characterized. As with its ? relative, YbcN showed a preference for binding ssDNA over duplex. Neither Orf nor YbcN displayed a significant preference for duplex DNA containing mismatches or 1-3 nucleotide bulges. YbcN also bound E. coli SSB, although unlike Orf, it failed to associate with an SSB mutant lacking the flexible C-terminal tail involved in coordinating heterologous protein-protein interactions. Residues conserved in the Orf family that flank the central cavity in the ? Orf crystal structure were targeted for mutagenesis to help determine the mode of DNA binding. Several of these mutant proteins showed significant defects in DNA binding consistent with the central aperture being important for substrate recognition. The widespread conservation of Orf-like proteins highlights the importance of targeting SSB coated ssDNA during lambdoid phage recombination. PMID:25083707

  8. Phage ORF family recombinases: conservation of activities and involvement of the central channel in DNA binding.

    PubMed

    Curtis, Fiona A; Malay, Ali D; Trotter, Alexander J; Wilson, Lindsay A; Barradell-Black, Michael M H; Bowers, Laura Y; Reed, Patricia; Hillyar, Christopher R T; Yeo, Robert P; Sanderson, John M; Heddle, Jonathan G; Sharples, Gary J

    2014-01-01

    Genetic and biochemical evidence suggests that ? Orf is a recombination mediator, promoting nucleation of either bacterial RecA or phage Red? recombinases onto single-stranded DNA (ssDNA) bound by SSB protein. We have identified a diverse family of Orf proteins that includes representatives implicated in DNA base flipping and those fused to an HNH endonuclease domain. To confirm a functional relationship with the Orf family, a distantly-related homolog, YbcN, from Escherichia coli cryptic prophage DLP12 was purified and characterized. As with its ? relative, YbcN showed a preference for binding ssDNA over duplex. Neither Orf nor YbcN displayed a significant preference for duplex DNA containing mismatches or 1-3 nucleotide bulges. YbcN also bound E. coli SSB, although unlike Orf, it failed to associate with an SSB mutant lacking the flexible C-terminal tail involved in coordinating heterologous protein-protein interactions. Residues conserved in the Orf family that flank the central cavity in the ? Orf crystal structure were targeted for mutagenesis to help determine the mode of DNA binding. Several of these mutant proteins showed significant defects in DNA binding consistent with the central aperture being important for substrate recognition. The widespread conservation of Orf-like proteins highlights the importance of targeting SSB coated ssDNA during lambdoid phage recombination. PMID:25083707

  9. KNAT6: An Arabidopsis Homeobox Gene Involved in Meristem Activity and Organ Separation[W

    PubMed Central

    Belles-Boix, Enric; Hamant, Olivier; Witiak, Sarah Melissa; Morin, Halima; Traas, Jan; Pautot, Véronique

    2006-01-01

    The homeobox gene family plays a crucial role during the development of multicellular organisms. The KNOTTED-like genes from Arabidopsis thaliana (KNAT6 and KNAT2) are close relatives of the meristematic genes SHOOT MERISTEMLESS (STM) and BREVIPEDICELLUS, but their function is not currently known. To investigate their role, we identified null alleles of KNAT6 and KNAT2. We demonstrate that KNAT6 contributes redundantly with STM to the maintenance of the shoot apical meristem (SAM) and organ separation. Consistent with this role, the expression domain of KNAT6 in the SAM marks the boundaries between the SAM and cotyledons. The lack of meristematic activity in the knat6 stm-2 double mutant and the fusion of cotyledons were linked to the modulation of CUP-SHAPED COTYLEDON (CUC) activity. During embryogenesis, KNAT6 is expressed later than STM and CUC. In agreement with this fact, CUC1 and CUC2 were redundantly required for KNAT6 expression. These data provide the basis for a model in which KNAT6 contributes to SAM maintenance and boundary establishment in the embryo via the STM/CUC pathway. KNAT2, although the closest related member of the family to KNAT6, did not have such a function. PMID:16798887

  10. Characterization of Streptococcal Platelet-Activating Factor Acetylhydrolase Variants That Are Involved in Innate Immune Evasion

    PubMed Central

    Liu, Guanghui; Liu, Mengyao; Xie, Gang

    2013-01-01

    Human pathogen group A streptococcus (GAS) has developed mechanisms to subvert innate immunity. We recently reported that the secreted esterase produced by serotype M1 GAS (SsEM1) reduces neutrophil recruitment by targeting platelet-activating factor (PAF). SsEM1 and SsE produced by serotype M28 GAS (SsEM28) have a 37% sequence difference. This study aims at determining whether SsEM28 is also a PAF acetylhydrolase and participates in innate immune evasion. We also examined whether SsE evolved to target PAF by characterizing the PAF acetylhydrolase (PAF-AH) activity and substrate specificity of SsEM1, SsEM28, SeE, the SsE homologue in Streptococcus equi, and human plasma PAF-AH (hpPAF-AH). PAF incubated with SsEM28 or SeE was converted into lyso-PAF. SsEM1 and SsEM28 had kcat values of 373 s?1 and 467 s?1, respectively, that were ?30-fold greater than that of hpPAF-AH (12 s?1). The comparison of SsEM1, SsEM28, and hpPAF-AH in kcat and Km in hydrolyzing triglycerides, acetyl esters, and PAF indicates that the SsE proteins are more potent hydrolases against PAF and have high affinity for PAF. SsEM28 possesses much lower esterase activities against triglycerides and other esters than SsEM1 but have similar potency with SsEM1 in PAF hydrolysis. Deletion of sseM28 in a covS deletion mutant of GAS increased neutrophil recruitment and reduced skin infection, whereas in trans expression of SsEM28 in GAS reduced neutrophil infiltration and increased skin invasion in subcutaneous infection of mice. These results suggest that the SsE proteins evolved to target PAF for enhancing innate immune evasion and skin invasion. PMID:23774595

  11. Involvement of protein kinase C in 5-HT-stimulated ciliary activity in Helisoma trivolvis embryos

    PubMed Central

    Christopher, Kimberley J; Young, Kevin G; Chang, John P; Goldberg, Jeffrey I

    1999-01-01

    During development, embryos of the pulmonate gastropod, Helisoma trivolvis, undergo a rotation behaviour due to the co-ordinated beating of three bands of ciliated epithelial cells. This behaviour is in part mediated by the neurotransmitter serotonin (5-HT) released from a pair of identified embryonic neurons. Using time-lapse videomicroscopy to measure ciliary beat frequency (CBF) in response to pharmacological manipulations, we determined whether protein kinase C (PKC) is involved in mediating 5-HT-stimulated ciliary beating.Diacylglycerol (DAG) analogues sn-1,2-dioctanoyl glycerol (DiC8; 100 ?M) and 1-oleoyl-2-acetyl-sn-glycerol (OAG; 100 ?M), partially mimicked the 5-HT-induced increase in CBF. In contrast, application of OAG in the absence of extracellular Ca2+ did not result in an increase in CBF.5-HT-stimulated CBF was effectively blocked by PKC inhibitors bisindolylmaleimide (10 and 100 nM) and calphostin C (10 nM). In addition, bisindolylmaleimide (100 nM) inhibited DiC8-induced increases in CBF. At a higher concentration (200 nM), bisindolylmaleimide did not significantly reduce 5-HT-stimulated cilio-excitation.Two different phorbol esters, phorbol 12-myristate 13-acetate (TPA; 0.1, 10 or 1000 nM) and phorbol 12?, 13?-dibenzoate (PDBn; 10 ?M) did not alter basal CBF. TPA (1 ?M) did not alter 5-HT-stimulated CBF. Likewise, the synthetic form of phosphatidylserine, N-(6-phenylhexyl)-5-chloro-1-naphthalenesulphonamide (SC-9; 10 ?M), did not increase CBF, whereas a strong increase in CBF was observed upon exposure to 5-HT.The results suggest that a DAG-dependent, phorbol ester-insensitive isoform of PKC mediates 5-HT-stimulated CBF in ciliated epithelial cells from embryos of Helisoma trivolvis. PMID:10050017

  12. Using Long-Distance Scientist Involvement to Enhance NASA Volunteer Network Educational Activities

    NASA Astrophysics Data System (ADS)

    Ferrari, K.

    2012-12-01

    Since 1999, the NASA/JPL Solar System Ambassadors (SSA) and Solar System Educators (SSEP) programs have used specially-trained volunteers to expand education and public outreach beyond the immediate NASA center regions. Integrating nationwide volunteers in these highly effective programs has helped optimize agency funding set aside for education. Since these volunteers were trained by NASA scientists and engineers, they acted as "stand-ins" for the mission team members in communities across the country. Through the efforts of these enthusiastic volunteers, students gained an increased awareness of NASA's space exploration missions through Solar System Ambassador classroom visits, and teachers across the country became familiarized with NASA's STEM (Science, Technology, Engineering and Mathematics) educational materials through Solar System Educator workshops; however the scientist was still distant. In 2003, NASA started the Digital Learning Network (DLN) to bring scientists into the classroom via videoconferencing. The first equipment was expensive and only schools that could afford the expenditure were able to benefit; however, recent advancements in software allow classrooms to connect to the DLN via personal computers and an internet connection. Through collaboration with the DLN at NASA's Jet Propulsion Laboratory and the Goddard Spaceflight Center, Solar System Ambassadors and Solar System Educators in remote parts of the country are able to bring scientists into their classroom visits or workshops as guest speakers. The goals of this collaboration are to provide special elements to the volunteers' event, allow scientists opportunities for education involvement with minimal effort, acquaint teachers with DLN services and enrich student's classroom learning experience.;

  13. Involvement of P2Y receptors in myocardial contractile activity of rats during postnatal ontogeny.

    PubMed

    Anikina, T A; Anisimova, I N; Sitdikov, F G

    2012-04-01

    We studied the effect of uridine 5'-triphosphate in concentrations of 10(-10)-10(-6) M on myocardial contractile activity in 7-100-day-old rats. Analysis of isometric contraction of myocardial strips showed that uridine 5'-triphosphate reduced the strength of myocardial contraction in rats of all age groups. In 21- and 100-day-old rat pups, exogenous uridine 5'-triphosphate produced a stronger inhibitory effect than in 7-day-old animals. The negative inotropic effect of UTP was abolished under conditions of P2Y(4) purinoceptor blockade with reagent blue-2. These data indicate that the effect of UTP on the myocardium is realized via P2Y(4) purinoceptors. PMID:22803161

  14. Mesenchymal glioma stem cells are maintained by activated glycolytic metabolism involving aldehyde dehydrogenase 1A3.

    PubMed

    Mao, Ping; Joshi, Kaushal; Li, Jianfeng; Kim, Sung-Hak; Li, Peipei; Santana-Santos, Lucas; Luthra, Soumya; Chandran, Uma R; Benos, Panayiotis V; Smith, Luke; Wang, Maode; Hu, Bo; Cheng, Shi-Yuan; Sobol, Robert W; Nakano, Ichiro

    2013-05-21

    Tumor heterogeneity of high-grade glioma (HGG) is recognized by four clinically relevant subtypes based on core gene signatures. However, molecular signaling in glioma stem cells (GSCs) in individual HGG subtypes is poorly characterized. Here we identified and characterized two mutually exclusive GSC subtypes with distinct dysregulated signaling pathways. Analysis of mRNA profiles distinguished proneural (PN) from mesenchymal (Mes) GSCs and revealed a pronounced correlation with the corresponding PN or Mes HGGs. Mes GSCs displayed more aggressive phenotypes in vitro and as intracranial xenografts in mice. Further, Mes GSCs were markedly resistant to radiation compared with PN GSCs. The glycolytic pathway, comprising aldehyde dehydrogenase (ALDH) family genes and in particular ALDH1A3, were enriched in Mes GSCs. Glycolytic activity and ALDH activity were significantly elevated in Mes GSCs but not in PN GSCs. Expression of ALDH1A3 was also increased in clinical HGG compared with low-grade glioma or normal brain tissue. Moreover, inhibition of ALDH1A3 attenuated the growth of Mes but not PN GSCs. Last, radiation treatment of PN GSCs up-regulated Mes-associated markers and down-regulated PN-associated markers, whereas inhibition of ALDH1A3 attenuated an irradiation-induced gain of Mes identity in PN GSCs. Taken together, our data suggest that two subtypes of GSCs, harboring distinct metabolic signaling pathways, represent intertumoral glioma heterogeneity and highlight previously unidentified roles of ALDH1A3-associated signaling that promotes aberrant proliferation of Mes HGGs and GSCs. Inhibition of ALDH1A3-mediated pathways therefore might provide a promising therapeutic approach for a subset of HGGs with the Mes signature. PMID:23650391

  15. Hydroxy-? sanshool induces colonic motor activity in rat proximal colon: a possible involvement of KCNK9

    PubMed Central

    Kubota, Kunitsugu; Ohtake, Nobuhiro; Ohbuchi, Katsuya; Mase, Akihito; Imamura, Sachiko; Sudo, Yuka; Miyano, Kanako; Yamamoto, Masahiro; Kono, Toru

    2015-01-01

    Various colonic motor activities are thought to mediate propulsion and mixing/absorption of colonic content. The Japanese traditional medicine daikenchuto (TU-100), which is widely used for postoperative ileus in Japan, accelerates colonic emptying in healthy humans. Hydroxy-? sanshool (HAS), a readily absorbable active ingredient of TU-100 and a KCNK3/KCNK9/KCNK18 blocker as well as TRPV1/TRPA1 agonist, has been investigated for its effects on colonic motility. Motility was evaluated by intraluminal pressure and video imaging of rat proximal colons in an organ bath. Distribution of KCNKs was investigated by RT-PCR, in situ hybridization, and immunohistochemistry. Current and membrane potential were evaluated with use of recombinant KCNK3- or KCNK9-expressing Xenopus oocytes and Chinese hamster ovary cells. Defecation frequency in rats was measured. HAS dose dependently induced strong propulsive “squeezing” motility, presumably as long-distance contraction (LDC). TRPV1/TRPA1 agonists induced different motility patterns. The effect of HAS was unaltered by TRPV1/TRPA1 antagonists and desensitization. Lidocaine (a nonselective KCNK blocker) and hydroxy-? sanshool (a geometrical isomer of HAS and KCNK3 blocker) also induced colonic motility as a rhythmic propagating ripple (RPR) and a LDC-like motion, respectively. HAS-induced “LDC,” but not lidocaine-induced “RPR,” was abrogated by a neuroleptic agent tetrodotoxin. KCNK3 and KCNK9 were located mainly in longitudinal smooth muscle cells and in neural cells in the myenteric plexus, respectively. Administration of HAS or TU-100 increased defecation frequency in normal and laparotomy rats. HAS may evoke strong LDC possibly via blockage of the neural KCNK9 channel in the colonic myenteric plexus. PMID:25634809

  16. Hydroxy-? sanshool induces colonic motor activity in rat proximal colon: a possible involvement of KCNK9.

    PubMed

    Kubota, Kunitsugu; Ohtake, Nobuhiro; Ohbuchi, Katsuya; Mase, Akihito; Imamura, Sachiko; Sudo, Yuka; Miyano, Kanako; Yamamoto, Masahiro; Kono, Toru; Uezono, Yasuhito

    2015-04-01

    Various colonic motor activities are thought to mediate propulsion and mixing/absorption of colonic content. The Japanese traditional medicine daikenchuto (TU-100), which is widely used for postoperative ileus in Japan, accelerates colonic emptying in healthy humans. Hydroxy-? sanshool (HAS), a readily absorbable active ingredient of TU-100 and a KCNK3/KCNK9/KCNK18 blocker as well as TRPV1/TRPA1 agonist, has been investigated for its effects on colonic motility. Motility was evaluated by intraluminal pressure and video imaging of rat proximal colons in an organ bath. Distribution of KCNKs was investigated by RT-PCR, in situ hybridization, and immunohistochemistry. Current and membrane potential were evaluated with use of recombinant KCNK3- or KCNK9-expressing Xenopus oocytes and Chinese hamster ovary cells. Defecation frequency in rats was measured. HAS dose dependently induced strong propulsive "squeezing" motility, presumably as long-distance contraction (LDC). TRPV1/TRPA1 agonists induced different motility patterns. The effect of HAS was unaltered by TRPV1/TRPA1 antagonists and desensitization. Lidocaine (a nonselective KCNK blocker) and hydroxy-? sanshool (a geometrical isomer of HAS and KCNK3 blocker) also induced colonic motility as a rhythmic propagating ripple (RPR) and a LDC-like motion, respectively. HAS-induced "LDC," but not lidocaine-induced "RPR," was abrogated by a neuroleptic agent tetrodotoxin. KCNK3 and KCNK9 were located mainly in longitudinal smooth muscle cells and in neural cells in the myenteric plexus, respectively. Administration of HAS or TU-100 increased defecation frequency in normal and laparotomy rats. HAS may evoke strong LDC possibly via blockage of the neural KCNK9 channel in the colonic myenteric plexus. PMID:25634809

  17. Is tyrosine kinase activation involved in basophil histamine release in asthma due to western red cedar?

    PubMed

    Frew, A; Chan, H; Salari, H; Chan-Yeung, M

    1998-02-01

    Occupational asthma due to western red cedar is associated with histamine release from basophils and mast cells on exposure to plicatic acid (PA), but the mechanisms underlying this response remain unclear. Specific kinase inhibitors were used to study the role of tyrosine and serine/threonine kinases in PA-induced histamine release from human basophils. Pretreatment with the tyrosine kinase inhibitor methyl 2,5-dihydroxy-cinnamate (MDHC) attenuated histamine release from basophils triggered by anti-IgE (29.8% inhibition; n = 15; P < 0.01) or grass pollen (48% inhibition; n = 6; P < 0.01). Inhibition was concentration-dependent and could be reversed by washing the cells in buffer, while the inactive stereoisomer of MDHC did not affect histamine release. In contrast, the protein kinase C inhibitor staurosporine did not affect histamine release by either anti-IgE or grass pollen. Pretreatment with MDHC partially inhibited PA-induced histamine release from basophils of 6/9 patients with red cedar asthma (25.4% vs 33.8%; P = NS). Staurosporine gave a similar level of inhibition of PA-induced histamine release (25.3% vs 33.8%; P = NS). Thus, signal transduction of the human basophil Fc epsilon RI appears to depend upon tyrosine kinase activation, but not on protein kinase C (serine/threonine kinase) activation. The lack of specific effect on plicatic acid-induced histamine release in basophils obtained from patients with occupational asthma due to western red cedar suggests that tyrosine kinases are not as important in this disease as in atopic asthma, and is consistent with the view that histamine release in red cedar asthma is largely IgE-independent. PMID:9534911

  18. Synchronized network activity in developing rat hippocampus involves regional hyperpolarization-activated cyclic nucleotide-gated (HCN) channel function

    PubMed Central

    Bender, Roland A.; Galindo, Rafael; Mameli, Manuel; Gonzalez-Vega, Rebeca; Valenzuela, C. Fernando; Baram, Tallie Z.

    2010-01-01

    The principal form of synchronized network activity in neonatal hippocampus consists of low frequency ‘giant depolarizing potentials’ (GDPs). Whereas contribution of both GABA and glutamate to their generation has been demonstrated, full understanding of the mechanisms underlying these synchronized activity bursts remains incomplete. A contribution of the h-current, conducted by HCN channels, to GDPs has been a topic of substantial interest. Here we focus on HCN1, the prevalent HCN channel isoform in neonatal hippocampus, and demonstrate an HCN1 spatiotemporal expression pattern in both CA3 principal cells and interneurons that correlates with the developmental profile of GDPs. Abrogation of HCN physiological function in CA3, via the selective Ih-blocker ZD7288, disrupts GDP generation. Furthermore, ZD7288 specifically abolishes spontaneous bursting of the CA3 pyramidal cells at frequencies typical of GDPs without major influence on interneuronal firing. These findings support a pivotal role for HCN channels expressed by CA3 neurons, and particularly CA3 pyramidal cells, in GDP-related network synchronization. PMID:16307610

  19. Understanding Scientists' Involvement in Education--Their Interests, Activities, and Needs: Research Results from the ReSciPE Project

    NASA Astrophysics Data System (ADS)

    Thiry, H.; Hunter, A.; Laursen, S.; Melton, G.

    2006-12-01

    The involvement of scientists in education has been cited by national leaders as essential for strengthening US science education at the K-12 and higher levels. While many individuals and groups have developed expertise in designing and implementing programs that engage scientists with students or teachers, there is little research evidence that helps us understand what motivates or discourages scientists from such involvement, the benefits and costs to them of participating, and the barriers they face that must be addressed to involve them effectively. The ReSciPE Project (Resources for Scientists in Partnership with Education) has offered a workshop on "Scientific Inquiry in the K-12 Classroom" to over 300 scientists and science educators across the US. These workshops have reached a wide audience of science professionals who undertake activities in science education, whether individual or institution-based work, for work or as a volunteer. The project aims to help these "education-engaged scientists" pursue their education work more effectively, but has also drawn on this group as a research sample for an evaluation-with-research study to investigate scientists' involvement in education. Pre- and post-surveys have enabled us to characterize the demographics of the participants and measure their self-reported knowledge and learning about education, especially inquiry-based science. Follow- up interviews have provided insight into their education activities, motivations, interests, difficulties, and needs. We will report on recent research findings from this study and place them in context of national needs and efforts to engage scientists in education.

  20. Unbalanced Activation of Glutathione Metabolic Pathways Suggests Potential Involvement in Plant Defense against the Gall Midge Mayetiola destructor in Wheat

    PubMed Central

    Liu, Xuming; Zhang, Shize; Whitworth, R. Jeff; Stuart, Jeffrey J.; Chen, Ming-Shun

    2015-01-01

    Glutathione, ?-glutamylcysteinylglycine, exists abundantly in nearly all organisms. Glutathione participates in various physiological processes involved in redox reactions by serving as an electron donor/acceptor. We found that the abundance of total glutathione increased up to 60% in resistant wheat plants within 72?hours following attack by the gall midge Mayetiola destructor, the Hessian fly. The increase in total glutathione abundance, however, is coupled with an unbalanced activation of glutathione metabolic pathways. The activity and transcript abundance of glutathione peroxidases, which convert reduced glutathione (GSH) to oxidized glutathione (GSSG), increased in infested resistant plants. However, the enzymatic activity and transcript abundance of glutathione reductases, which convert GSSG back to GSH, did not change. This unbalanced regulation of the glutathione oxidation/reduction cycle indicates the existence of an alternative pathway to regenerate GSH from GSSG to maintain a stable GSSG/GSH ratio. Our data suggest the possibility that GSSG is transported from cytosol to apoplast to serve as an oxidant for class III peroxidases to generate reactive oxygen species for plant defense against Hessian fly larvae. Our results provide a foundation for elucidating the molecular processes involved in glutathione-mediated plant resistance to Hessian fly and potentially other pests as well. PMID:25627558

  1. Unbalanced Activation of Glutathione Metabolic Pathways Suggests Potential Involvement in Plant Defense against the Gall Midge Mayetiola destructor in Wheat.

    PubMed

    Liu, Xuming; Zhang, Shize; Whitworth, R Jeff; Stuart, Jeffrey J; Chen, Ming-Shun

    2015-01-01

    Glutathione, ?-glutamylcysteinylglycine, exists abundantly in nearly all organisms. Glutathione participates in various physiological processes involved in redox reactions by serving as an electron donor/acceptor. We found that the abundance of total glutathione increased up to 60% in resistant wheat plants within 72?hours following attack by the gall midge Mayetiola destructor, the Hessian fly. The increase in total glutathione abundance, however, is coupled with an unbalanced activation of glutathione metabolic pathways. The activity and transcript abundance of glutathione peroxidases, which convert reduced glutathione (GSH) to oxidized glutathione (GSSG), increased in infested resistant plants. However, the enzymatic activity and transcript abundance of glutathione reductases, which convert GSSG back to GSH, did not change. This unbalanced regulation of the glutathione oxidation/reduction cycle indicates the existence of an alternative pathway to regenerate GSH from GSSG to maintain a stable GSSG/GSH ratio. Our data suggest the possibility that GSSG is transported from cytosol to apoplast to serve as an oxidant for class III peroxidases to generate reactive oxygen species for plant defense against Hessian fly larvae. Our results provide a foundation for elucidating the molecular processes involved in glutathione-mediated plant resistance to Hessian fly and potentially other pests as well. PMID:25627558

  2. Differential Pro-Inflammatory Responses of Astrocytes and Microglia Involve STAT3 Activation in Response to 1800 MHz Radiofrequency Fields

    PubMed Central

    Lu, Yonghui; He, Mindi; Zhang, Yang; Xu, Shangcheng; Zhang, Lei; He, Yue; Chen, Chunhai; Liu, Chuan; Pi, Huifeng; Yu, Zhengping; Zhou, Zhou

    2014-01-01

    Microglia and astrocytes play important role in maintaining the homeostasis of central nervous system (CNS). Several CNS impacts have been postulated to be associated with radiofrequency (RF) electromagnetic fields exposure. Given the important role of inflammation in neural physiopathologic processes, we investigated the pro-inflammatory responses of microglia and astrocytes and the involved mechanism in response to RF fields. Microglial N9 and astroglial C8-D1A cells were exposed to 1800 MHz RF for different time with or without pretreatment with STAT3 inhibitor. Microglia and astrocytes were activated by RF exposure indicated by up-regulated CD11b and glial fibrillary acidic protein (GFAP). However, RF exposure induced differential pro-inflammatory responses in astrocytes and microglia, characterized by different expression and release profiles of IL-1?, TNF-?, IL-6, PGE2, nitric oxide (NO), inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX2). Moreover, the RF exposure activated STAT3 in microglia but not in astrocytes. Furthermore, the STAT3 inhibitor Stattic ameliorated the RF-induced release of pro-inflammatory cytokines in microglia but not in astrocytes. Our results demonstrated that RF exposure differentially induced pro-inflammatory responses in microglia and astrocytes, which involved differential activation of STAT3 in microglia and astrocytes. Our data provide novel insights into the potential mechanisms of the reported CNS impacts associated with mobile phone use and present STAT3 as a promising target to protect humans against increasing RF exposure. PMID:25275372

  3. Peroxidase Activity and Involvement in the Oxidative Stress Response of Roseobacter denitrificans Truncated Hemoglobin

    PubMed Central

    Wang, Yaya; Barbeau, Xavier; Bilimoria, Astha; Lagüe, Patrick; Couture, Manon; Tang, Joseph Kuo-Hsiang

    2015-01-01

    Roseobacter denitrificans is a member of the widespread marine Roseobacter genus. We report the first characterization of a truncated hemoglobin from R. denitrificans (Rd. trHb) that was purified in the heme-bound form from heterologous expression of the protein in Escherichia coli. Rd. trHb exhibits predominantly alpha-helical secondary structure and absorbs light at 412, 538 and 572 nm. The phylogenetic classification suggests that Rd. trHb falls into group II trHbs, whereas sequence alignments indicate that it shares certain important heme pocket residues with group I trHbs in addition to those of group II trHbs. The resonance Raman spectra indicate that the isolated Rd. trHb contains a ferric heme that is mostly 6-coordinate low-spin and that the heme of the ferrous form displays a mixture of 5- and 6-coordinate states. Two Fe-His stretching modes were detected, notably one at 248 cm-1, which has been reported in peroxidases and some flavohemoglobins that contain an Fe-His-Asp (or Glu) catalytic triad, but was never reported before in a trHb. We show that Rd. trHb exhibits a significant peroxidase activity with a (kcat/Km) value three orders of magnitude higher than that of bovine Hb and only one order lower than that of horseradish peroxidase. This enzymatic activity is pH-dependent with a pKa value ~6.8. Homology modeling suggests that residues known to be important for interactions with heme-bound ligands in group II trHbs from Mycobacterium tuberculosis and Bacillus subtilis are pointing toward to heme in Rd. trHb. Genomic organization and gene expression profiles imply possible functions for detoxification of reactive oxygen and nitrogen species in vivo. Altogether, Rd. trHb exhibits some distinctive features and appears equipped to help the bacterium to cope with reactive oxygen/nitrogen species and/or to operate redox biochemistry. PMID:25658318

  4. Arf-1 (ADP-ribosylation factor-1) is involved in the activation of a mammalian Na+-selective current.

    PubMed Central

    Straube, Sebastian; Parekh, Anant B

    2004-01-01

    Stimulation of mammalian cells often results in an increase in the intracellular Na(+) concentration, brought about by Na(+) influx into the cell via Na(+)-permeable ion channels. In some cell types, particularly renal epithelia and mast cells, non-hydrolysable analogues of GTP, such as GTP[S] (guanosine 5'-[gamma-thio]triphosphate), activate a non-voltage-activated Na(+)-selective current. We have carried out whole-cell patch-clamp experiments to examine how GTP[S] activates the Na(+) current in a rat mast cell line. The ability of GTP[S] to activate Na(+) influx was prevented by including GTP in the pipette solution, indicating the involvement of small G-proteins. Brefeldin A and Arf-1-(2-17), inhibitors of Arf-1 (ADP-ribosylation factor-1) proteins, suppressed the activation of Na(+) entry by GTP[S]. However, non-active succinylated Arf-1-(2-17) or an N-terminal myristoylated peptide directed towards Arf-5 were ineffective. Arf proteins modulate the cytoskeleton, and disruption of the cytoskeleton with cytochalasin D or its stabilization with phalloidin impaired the development of the Na(+) current. Disaggregation of microtubules was without effect. Dialysis with cAMP or inhibition of cAMP phosphodiesterase with caffeine both decreased the extent of Na(+) entry, and this was not prevented by pre-treatment with broad-spectrum protein kinase inhibitors. Collectively, our results suggest that the mechanism of activation of a mammalian non-voltage-activated Na(+)-selective current requires an Arf small G-protein, most probably Arf-1. PMID:14563210

  5. Thrombin Activates AMP-Activated Protein Kinase in Endothelial Cells via a Pathway Involving Ca2+/Calmodulin-Dependent Protein Kinase Kinase ?

    PubMed Central

    Stahmann, Nadine; Woods, Angela; Carling, David; Heller, Regine

    2006-01-01

    AMP-activated protein kinase (AMPK) is a sensor of cellular energy state in response to metabolic stress and other regulatory signals. AMPK is controlled by upstream kinases which have recently been identified as LKB1 or Ca2+/calmodulin-dependent protein kinase kinase ? (CaMKK?). Our study of human endothelial cells shows that AMPK is activated by thrombin through a Ca2+-dependent mechanism involving the thrombin receptor protease-activated receptor 1 and Gq-protein-mediated phospholipase C activation. Inhibition of CaMKK with STO-609 or downregulation of CaMKK? using RNA interference decreased thrombin-induced AMPK activation significantly, indicating that CaMKK? was the responsible AMPK kinase. In contrast, downregulation of LKB1 did not affect thrombin-induced AMPK activation but abolished phosphorylation of AMPK with 5-aminoimidazole-4-carboxamide ribonucleoside. Thrombin stimulation led to phosphorylation of acetyl coenzyme A carboxylase (ACC) and endothelial nitric oxide synthase (eNOS), two downstream targets of AMPK. Inhibition or downregulation of CaMKK? or AMPK abolished phosphorylation of ACC in response to thrombin but had no effect on eNOS phosphorylation, indicating that thrombin-stimulated phosphorylation of eNOS is not mediated by AMPK. Our results underline the role of Ca2+ as a regulator of AMPK activation in response to a physiologic stimulation. We also demonstrate that endothelial cells possess two pathways to activate AMPK, one Ca2+/CaMKK? dependent and one AMP/LKB1 dependent. PMID:16880506

  6. Attributes of Dental Trauma in a School Population with Active Sports Involvement

    PubMed Central

    Prabhu, Anand; Rao, Arun Prasad; Govindarajan, Mohan; Reddy, Venugopal; Krishnakumar, Ramalingam; Kaliyamoorthy, Sugumaran

    2013-01-01

    Purpose Dental trauma has become an important aspect of dental public health. The primary requisite before actively dealing with such problems is to describe the extent, distribution, and variables associated with the specific condition. The purpose of this study was to assess the prevalence and role of socioeconomic status and anatomic risk factors in traumatic dental injuries (TDI) to permanent anterior teeth in 10 to 16 year old Sainik (Army) school, children in India. Methods A cross-sectional study was conducted. Data was collected through a survey form and clinical examination. The permanent anterior teeth of four hundred and forty six male school children were examined for TDI. The socio-economic status, lip coverage and overjet were recorded. Statistical significance for the association between occurrence of TDI and the various risk factors was carried out. Results The prevalence of TDI to permanent anterior teeth was 23.8%. A large number of injuries occurred during participation in sports. Inadequate lip coverage and a large maxillary overjet were identified as important predictors for dental trauma. Conclusion A high prevalence of dental trauma was observed in the study population suggestive of low awareness regarding the cause, effects and prevention of the condition. PMID:24427477

  7. Possible involvement of activated locus coeruleus-noradrenergic neurons in pain-related sleep disorders.

    PubMed

    Koh, Keito; Hamada, Asami; Hamada, Yusuke; Yanase, Makoto; Sakaki, Mamiko; Someya, Kazuki; Narita, Michiko; Kuzumaki, Naoko; Ikegami, Daigo; Sakai, Hiroyasu; Iseki, Masako; Inada, Eiichi; Narita, Minoru

    2015-03-01

    The locus coeruleus (LC) is a noradrenergic brainstem structure that is considered to play a role in promoting arousal. To further clarify the role of LC noradrenergic neurons, we performed an optogenetic assay by injecting AAV-channelrhodopsin-2 (ChR2) into the LC of cre-tyrosine hydrolase (TH) mice. We found here that the specific activation of LC noradrenergic neurons produced a significant increase in wakefulness and a significant decrease in non-rapid eye movement (NREM) sleep during photostimulation. On the other hand, neuropathic pain is believed to significantly interfere with sleep, and inadequate sleep may contribute to the stressful negative consequences of living with pain. In the present study, sciatic nerve ligation, which produced significant thermal hyperalgesia, significantly increased the levels of noradrenaline released in the prefrontal cortex (PFC) by the weak electrical stimulation of neurons in the LC. Under these conditions, the systemic administration of adrenaline ? and ? inhibitor cocktail at 7 days after sciatic nerve ligation restored the increased wakefulness and decreased NREM sleep to normal levels. These results suggest that neuropathic pain may accelerate neurons in the LC, and its overactivation may be, at least in part, associated with sleep disturbance under neuropathic pain. PMID:25481765

  8. Growth hormone activity in mitochondria depends on GH receptor Box 1 and involves caveolar pathway targeting

    SciTech Connect

    Perret-Vivancos, Cecile [CNRS UMR 5123, Bat. R. Dubois, Universite Claude Bernard-Lyon 1, 43 Bd du 11 Novembre 1918, 69622 Villeurbanne cedex (France); Abbate, Aude [CNRS UMR 5123, Bat. R. Dubois, Universite Claude Bernard-Lyon 1, 43 Bd du 11 Novembre 1918, 69622 Villeurbanne cedex (France); Ardail, Dominique [INSERM U189-Faculte de medecine Lyon Sud, 69921 Oullins cedex (France); Raccurt, Mireille [CNRS UMR 5123, Bat. R. Dubois, Universite Claude Bernard-Lyon 1, 43 Bd du 11 Novembre 1918, 69622 Villeurbanne cedex (France); Usson, Yves [UMR 5525 CNRS, Institut de l'Ingenierie de l'Information de Sante (IN3S) Domaine de la Merci, Universite Joseph Fourier, 38706 La Tronche cedex (France); Lobie, Peter E. [Liggins Institute, University of Aukland, 2-6 Park Avenue, Private Bag, Aukland 92019 (New Zealand); Morel, Gerard [CNRS UMR 5123, Bat. R. Dubois, Universite Claude Bernard-Lyon 1, 43 Bd du 11 Novembre 1918, 69622 Villeurbanne cedex (France)]. E-mail: gerard.morel@univ-lyon1.fr

    2006-02-01

    Growth hormone (GH) binding to its receptor (GHR) initiates GH-dependent signal transduction and internalization pathways to generate the biological effects. The precise role and way of action of GH on mitochondrial function are not yet fully understood. We show here that GH can stimulate cellular oxygen consumption in CHO cells transfected with cDNA coding for the full-length GHR. By using different GHR cDNA constructs, we succeeded in determining the different parts of the GHR implicated in the mitochondrial response to GH. Polarography and two-photon excitation fluorescence microscopy analysis showed that the Box 1 of the GHR intracellular domain was required for an activation of the mitochondrial respiration in response to a GH exposure. However, confocal laser scanning microscopy demonstrated that cells lacking the GHR Box 1 could efficiently internalize the hormone. We demonstrated that internalization mediated either by clathrin-coated pits or by caveolae was able to regulate GH mitochondrial effect: these two pathways are both essential to obtain the GH stimulatory action on mitochondrial function. Moreover, electron microscopic and biochemical approaches allowed us to identify the caveolar pathway as essential for targeting GH and GHR to mitochondria.

  9. Calmodulin Involvement in Stress-Activated Nuclear Localization of Albumin in JB6 Epithelial Cells.

    SciTech Connect

    Weber, Thomas J.; Negash, Sewite; Smallwood, Heather S.; Ramos, Kenneth S.; Thrall, Brian D.; Squier, Thomas C.

    2004-06-15

    We report that in response to oxidative stress, albumin is translocated to the nucleus where it binds in concert with known transcription factors to an antioxidant response element (ARE), which controls the expression of glutathione-S-transferase and other antioxidant enzymes, functioning to mediate adaptive cellular responses. To investigate the mechanisms underlying this adaptive cell response, we have identified linkages between calcium signaling and the nuclear translocation of albumin in JB6 epithelial cells. Under resting conditions, albumin and the calcium regulatory protein, calmodulin (CaM), co-immunoprecipitate using antibodies against either protein, indicating a tight association. Calcium activation of CaM disrupts the association between CaM and albumin, suggesting that transient increases in cytosolic calcium levels function to mobilize intracellular albumin to facilitate its translocation into the nucleus. Likewise, nuclear translocation of albumin is induced by exposure of cells to hydrogen peroxide or a phorbol ester, indicating a functional linkage between reactive oxygen species, calcium, and PKC-signaling pathways. Inclusion of an antioxidant enzyme (i.e., superoxide dismutase) blocks nuclear translocation, suggesting that the oxidation of sensitive proteins functions to coordinate the adaptive cellular response. These results suggest that elevated calcium transients, and associated increases in reactive oxygen species, contribute to adaptive cellular responses through the mobilization and nuclear translocation of cellular albumin to mediate the transcriptional regulation of antioxidant responsive elements.

  10. Photosynthetic activity influences cellulose biosynthesis and phosphorylation of proteins involved therein in Arabidopsis leaves.

    PubMed

    Boex-Fontvieille, Edouard; Davanture, Marlène; Jossier, Mathieu; Zivy, Michel; Hodges, Michael; Tcherkez, Guillaume

    2014-09-01

    Cellulose is one of the most important organic compounds in terrestrial ecosystems and represents a major plant structural polymer. However, knowledge of the regulation of cellulose biosynthesis is still rather limited. Recent studies have shown that the phosphorylation of cellulose synthases (CESAs) may represent a key regulatory event in cellulose production. However, the impact of environmental conditions on the carbon flux of cellulose deposition and on phosphorylation levels of CESAs has not been fully elucidated. Here, we took advantage of gas exchange measurements, isotopic techniques, metabolomics, and quantitative phosphoproteomics to investigate the regulation of cellulose production in Arabidopsis rosette leaves in different photosynthetic contexts (different CO2 mole fractions) or upon light/dark transition. We show that the carbon flux to cellulose production increased with photosynthesis, but not proportionally. The phosphorylation level of several phosphopeptides associated with CESA1 and 3, and several enzymes of sugar metabolism was higher in the light and/or increased with photosynthesis. By contrast, a phosphopeptide (Ser126) associated with CESA5 seemed to be more phosphorylated in the dark. Our data suggest that photosynthetic activity affects cellulose deposition through the control of both sucrose metabolism and cellulose synthesis complexes themselves by protein phosphorylation. PMID:25039072

  11. The Department of Kinesiology and Physical Education offers courses in theoretical perspectives of the study of human movement and the practical application of physical activity involvement. A

    E-print Network

    Seldin, Jonathan P.

    of the study of human movement and the practical application of physical activity involvement. A multidisciplinary field, Kinesiology provides students with a broad perspective for studying physical activity activity across the lifespan are examined. The study of physical activity/sport as a socializing agent

  12. Involvement of platelet-activating factor (PAF) in endotoxin-induced intestinal motor disturbances in rats.

    PubMed

    Pons, L; Droy-Lefaix, M T; Braquet, P; Buéno, L

    1989-01-01

    Intestinal myoelectrical activity was investigated in conscious fasted rats chronically implanted with Nichrome electrodes in the duodeno-jejunum. Motility of the small intestine was characterized by the presence of migrating myoelectric complex (MMC) occurring regularly at 16.2 +/- 5.8 minute intervals. Intravenous administration of endotoxin (E. coli S.0111:B4) at a dose of 50 micrograms/kg increased the interval between MMC to 112.6 +/- 26.8 min, the duration of these effects being dose-related between 10 to 100 micrograms/kg. Such a typical myoelectrical alteration, corresponding to rapidly propagated groups of spike bursts, was mimicked by the IP administration of PAF at doses of 10 to 50 micrograms/kg. Previous administration of BN 52021, a specific PAF antagonist at a dose of 50 mg/kg abolished the motor alterations induced by IP injection of PAF (25 micrograms/kg) and significantly (p less than 0.01) reduced by 61.2% those induced by IV endotoxin (50 micrograms/kg). Indomethacin (10 mg/kg IP) as well as SC 19220 (5 mg/kg IV), a PGE2 antagonist, injected prior to endotoxin (50 micrograms/kg IV) or PAF (25 micrograms/kg IP) also reduced significantly (p less than 0.01) the duration of MMC inhibition. It is concluded that endogenous release of PAF is partly responsible for the intestinal motor alterations induced by endotoxin; these effects, strongly reduced after treatment with BN 52021, are also mediated through the release of prostaglandins. PMID:2570338

  13. Peroxiredoxin 2 is involved in vasculogenic mimicry formation by targeting VEGFR2 activation in colorectal cancer.

    PubMed

    Zhang, Shouru; Fu, Zhongxue; Wei, Jinlai; Guo, Jinbao; Liu, Maoxi; Du, Kunli

    2015-01-01

    The mammalian peroxiredoxin 2 (Prdx2) is a member of thiol-dependent antioxidant proteins and plays an important role in the progression of colorectal cancer (CRC). The aim of this study was to confirm the role of Prdx2 in formation of VM and progression of CRC. Immunohistochemistry and CD34/periodic acid Schiff double staining were performed to explore the expression of Prdx2 and VM formation in 70 CRC tissues, and there was a positive correlation between Prdx2 expression and VM formation by the Pearson correlation coefficient (r = 0.282, p < 0.05). Prdx2 was suppressed in poorly differentiated HCT116 cells by Prdx2-siRNA-LV transduction. The expression of Prdx2 at both mRNA and protein levels in HCT116 cells transfected with the Prdx2 siRNA was significantly lower than that of negative control siRNA as confirmed by quantitative real-time PCR and Western blotting analysis, respectively (p < 0.05). The well-established in vitro 3D culture model was chosen to investigate the VM formation of HCT116 cells. The numbers of the tubular structures were significantly fewer in Prdx2 siRNA explants than those of negative control siRNA explants after VEGF induction (p < 0.05). Although VEGFR2 expressions had no change after VEGF induction, we found that VEGFR2 phosphorylation levels were markedly reduced in cells of siPrdx2 over time compared with those of negative control siRNA by Western blotting analysis (p < 0.05, p < 0.01). The effects of Prdx2 siRNA on the invasive capabilities of HCT116 cells with VEGF induction were examined by using Matrigel invasion chamber assay. The invasive capabilities of HCT116 cells were significantly declined in Prdx2 siRNA explants than those of negative control siRNA explants (p < 0.05). The effects of Prdx2 siRNA on pathological tumor growth were examined by using a tumor xenograft model in vivo. After implant of HCT116 cells that transduced with Prdx2 siRNA and negative control siRNA as xenografts into nude mice, the growth of xenograft tumors with Prdx2 siRNA was much slower than that of negative control siRNA, and the volumes of tumor xenografts with Prdx2 siRNA were smaller than those of negative control siRNA after 5 weeks (p < 0.05). Further conclusion showed that Prdx2 regulates VM formation by targeting VEGFR2 activation, which now represents as a therapeutic target for RC. PMID:25471788

  14. Involvement of Nrf2 activation in resistance to 5-fluorouracil in human colon cancer HT-29 cells.

    PubMed

    Akhdar, Hanane; Loyer, Pascal; Rauch, Claudine; Corlu, Anne; Guillouzo, André; Morel, Fabrice

    2009-08-01

    Acquisition of drug resistance by cancer cells is attributed to various factors including alterations in apoptotic pathways, enhanced expression of multidrug resistance-associated proteins, altered drug metabolism or uptake and/or overexpression of cytoprotective genes. Thus, potential induction of defence pathways by anticancer drugs might have a marked incidence on cancer cell resistance. 5-Fluorouracil (5-FU) remains the most commonly used anticancer drug for the treatment of colorectal cancer, although objective response rates are as low as 20%. The aim of our study was to investigate the effects of 5-FU on cytoprotective systems in human colon HT-29 cells. Our results demonstrate that 5-FU induced the expression of mRNAs encoding glutathione transferases and antioxidant enzymes. To further determine the mechanisms involved in 5-FU effects, we investigated whether it activates the Nrf2/antioxidant response element pathway which is implicated in the regulation of several genes involved in cytoprotection. Translocation of Nrf2 into the nucleus after 5-FU exposure was demonstrated by immunocytochemistry and western blotting. Using an ARE-driven reporter gene assay, activation of the luciferase activity by 5-FU was also evidenced. Moreover, transfection of HT-29 cells with siRNA directed against Nrf2 inhibited induction of Nrf2 target genes and increased 5-FU cytotoxicity. In conclusion, we demonstrate for the first time that 5-FU activates the Nrf2/ARE pathway which in turn induces cytoprotective genes and modulates chemosensitivity of HT-29 colon cancer cells. Therefore, we postulate that Nrf2 might represent a potential therapeutic target in 5-FU treatment of colon cancer. PMID:19524433

  15. The neuropeptide Y Y1 receptor knockdown modulates activator protein 1-involved feeding behavior in amphetamine-treated rats

    PubMed Central

    2013-01-01

    Background Hypothalamic neuropeptide Y (NPY) and two immediate early genes, c-fos and c-jun, have been found to be involved in regulating the appetite-suppressing effect of amphetamine (AMPH). The present study investigated whether cerebral catecholamine (CA) might regulate NPY and POMC expression and whether NPY Y1 receptor (Y1R) participated in activator protein-1 (AP-1)–mediated feeding. Methods Rats were given AMPH daily for 4 days. Changes in the expression of NPY, Y1R, c-Fos, c-Jun, and AP-1 were assessed and compared. Results Decreased CA could modulate NPY and melanocortin receptor 4 (MC4R) expressions. NPY and food intake decreased the most on Day 2, but Y1R, c-Fos, and c-Jun increased by approximately 350%, 280%, and 300%, respectively, on Day 2. Similarly, AP-1/DNA binding activity was increased by about 180% on Day 2. The expression patterns in Y1R, c-Fos, c-Jun, and AP-1/DNA binding were opposite to those in NPY during AMPH treatment. Y1R knockdown was found to modulate the opposite regulation between NPY and AP-1, revealing an involvement of Y1R in regulating NPY/AP-1–mediated feeding. Conclusions These results point to a molecular mechanism of CA/NPY/Y1R/AP-1 signaling in the control of AMPH-mediated anorexia and may advance the medical research of anorectic and anti-obesity drugs. PMID:24225225

  16. Metatranscriptome of an Anaerobic Benzene-Degrading, Nitrate-Reducing Enrichment Culture Reveals Involvement of Carboxylation in Benzene Ring Activation

    PubMed Central

    Luo, Fei; Gitiafroz, Roya; Devine, Cheryl E.; Gong, Yunchen; Hug, Laura A.; Raskin, Lutgarde

    2014-01-01

    The enzymes involved in the initial steps of anaerobic benzene catabolism are not known. To try to elucidate this critical step, a metatranscriptomic analysis was conducted to compare the genes transcribed during the metabolism of benzene and benzoate by an anaerobic benzene-degrading, nitrate-reducing enrichment culture. RNA was extracted from the mixed culture and sequenced without prior mRNA enrichment, allowing simultaneous examination of the active community composition and the differential gene expression between the two treatments. Ribosomal and mRNA sequences attributed to a member of the family Peptococcaceae from the order Clostridiales were essentially only detected in the benzene-amended culture samples, implicating this group in the initial catabolism of benzene. Genes similar to each of two subunits of a proposed benzene-carboxylating enzyme were transcribed when the culture was amended with benzene. Anaerobic benzoate degradation genes from strict anaerobes were transcribed only when the culture was amended with benzene. Genes for other benzoate catabolic enzymes and for nitrate respiration were transcribed in both samples, with those attributed to an Azoarcus species being most abundant. These findings indicate that the mineralization of benzene starts with its activation by a strict anaerobe belonging to the Peptococcaceae, involving a carboxylation step to form benzoate. These data confirm the previously hypothesized syntrophic association between a benzene-degrading Peptococcaceae strain and a benzoate-degrading denitrifying Azoarcus strain for the complete catabolism of benzene with nitrate as the terminal electron acceptor. PMID:24795366

  17. Involvement of glycogen synthase kinase-3beta in hydrogen peroxide-induced suppression of Tcf/Lef-dependent transcriptional activity.

    PubMed

    Shin, Soon Young; Chin, Byung Rho; Lee, Young Han; Kim, Jung-Hye

    2006-05-01

    Hydrogen peroxide (H(2)O(2)) mediates induction of cytotoxicity in various cell types. GSK-3beta has been found to participate in a number of signaling pathways, including cell proliferation and cell death. In the present study, we show that GSK-3beta is rapidly dephosphorylated and activated in response to H(2)O(2) treatment. H(2)O(2) also dephosphorylates Akt/PKB in a dose- and time-dependent manner. Overexpression of Akt/PKB attenuates H(2)O(2)-induced dephosphorylation of GSK-3beta. Ectopic expression of Dvl-1, a component of Wnt signaling, stimulates Akt/PKB and inhibits dephosphorylation of GSK-3beta by H(2)O(2). Furthermore, H(2)O(2) causes the reduction of beta-catenin level and LiCl-mediated activation of Tcf/Lef-dependent transcription activity. These findings suggest that GSK-3beta is involved in H(2)O(2)-mediated inhibition of Tcf/Lef-dependent transcriptional activity. PMID:15993040

  18. Characterisation of two novel CYP4 genes from the marine polychaete Nereis virens and their involvement in pyrene hydroxylase activity.

    PubMed

    Jørgensen, Anne; Rasmussen, Lene Juel; Andersen, Ole

    2005-10-28

    Cytochrome P450 enzymes (CYP enzymes) catalyse the initial step in biotransformation of xenobiotics like polycyclic aromatic hydrocarbons (PAHs). The marine polychaete Nereis virens has a high capacity for biotransformation of PAHs. In the present study, the complete cDNA sequences of two novel CYP genes isolated from N. virens gut tissue are reported. One named CYP342A1, the first member of a new family and the other named CYP4BB1, the first member of a new subfamily. This is the first investigation of specific CYP enzymes from marine polychaetes in which catalytic activity has been determined. Both CYP enzymes had monooxygenase activity and catalysed hydroxylation of pyrene to 1-hydroxypyrene. Based on the present results it is likely that both CYP4BB1 and CYP342A1 are involved in xenobiotic biotransformation. Furthermore, site-directed mutagenesis of the conserved cysteine residue of the heme binding domain resulted in complete loss of monooxygenase activity of both CYP enzymes, indicating that this cysteine residue is indispensable for monooxygenase activity of invertebrate CYP enzymes, as has been well documented in vertebrates. Considering the important role of CYP enzymes in biotransformation of xenobiotics and the presence of N. virens in estuarine environments that accumulates organic xenobiotics, our results are important in understanding the molecular mechanism of biotransformation in marine polychaetes. PMID:16154110

  19. Involvement of protein kinase D in Fc gamma-receptor activation of the NADPH oxidase in neutrophils.

    PubMed Central

    Davidson-Moncada, Jan K; Lopez-Lluch, Guillermo; Segal, Anthony W; Dekker, Lodewijk V

    2002-01-01

    Protein kinases involved in the activation of the NADPH oxidase by Fc gamma receptors in neutrophils were studied. Of three different protein kinase C (PKC) inhibitors, Gö 6976 inhibited the NADPH oxidase completely, whereas bisindolylmaleimide I and Ro 31-8220 caused a 70-80% inhibition. Thus a Gö 6976-sensitive, bisindolylmaleimide I/Ro 31-8220-insensitive component contributes to NADPH oxidase activation induced by Fc gamma receptors. Down-regulation of PKC isotypes resulted in inhibition of Fc gamma-receptor-activated NADPH oxidase, but a down-regulation-insensitive component was still present. This component was sensitive to Gö 6976, but insensitive to Ro 31-8220. It has been shown previously that protein kinase D/PKC-mu (PKD) shows this same pharmacology in vitro. We show that PKD is present in neutrophils and that, in contrast with PKC isotypes, PKD is not down-regulated. Therefore PKD may participate in NADPH oxidase activation. To obtain direct evidence for this we adopted an antisense approach. Antisense PKD inhibited NADPH oxidase induced by Fc gamma-receptor stimulation by 50% and the Ro 31-8220-insensitive component in the activation was inhibited by antisense PKD. In vitro kinase assays showed that PKD is activated by presenting IgG-opsonized particles to neutrophils. Furthermore, PKD localizes to the area of particle intake in the cell and phosphorylates two of the three cytosolic components of the NADPH oxidase, p40(phox) and p47(phox). Taken together, these data indicate that Fc gamma receptors engage PKD in the regulation of the NADPH oxidase. PMID:11903052

  20. PmPPAF is a pro-phenoloxidase activating factor involved in innate immunity response of the shrimp Penaeus monodon.

    PubMed

    Ma, Tracy H T; Benzie, John A H; He, Jian-Guo; Sun, Cheng-Bo; Chan, Siuming F

    2014-05-01

    One of the major steps in the innate immune response of shrimp includes the activation of serine proteinases of the pro-phenoloxidase pathway by the prophenoloxidase activation enzyme (PPAF). In this study, the cDNA encoding a serine proteinase homologue (SPH) with prophenoloxidase activating activity of Penaeus monodon (PmPPAF) was cloned and characterized. PmPPAF cDNA consists of 1444 nucleotides encoding a protein with 394 amino acid residues. The estimated molecular weight of PmPPAF is 43.5 kDa with an isoelectric point of 5.19. PmPPAF consists of a signal peptide, a CLIP domain and a carboxyl-terminal trypsin-like serine protease domain. It is highly similar to the masquerade-like protein 2A (61% similarity) of the crayfish Pacifastacus leniusculus, other serine proteases (42.9-67% identity) of P. monodon, and the PPAF of the crab (61% similarity). Unlike other SPH of P. monodon, which express mainly in the hemocytes, PmPPAF transcripts were detected in the hemocytes, eyestalk, hypodermis, gill, swimming leg and brain. Similar to the crab PPAF, PmPPAF transcript level is high in shrimp at the premolt stages and PmPPAF expression is up-regulated in shrimp infected with white spot syndrome virus (WSSV). Gene silencing of PmPPAF decreased expression of a prophenoloxidase-like gene and injection of Anti-PmPPAF antibody causes a decrease in PO activity. Taken together, these results provided evidence that PmPPAF is a serine proteinase homologue, and is involved in the pro-PO activation pathway of the shrimp innate immune system. PMID:24345607

  1. Potential of laticifer fluids for inhibiting Aedes aegypti larval development: evidence for the involvement of proteolytic activity.

    PubMed

    Ramos, Márcio V; Pereira, Danielle A; Souza, Diego P; Araújo, Eliane S; Freitas, Cléverson Dt; Cavalheiro, Mariana G; Matos, Mayara Patricia V; Carvalho, Ana Fu

    2009-09-01

    It has been shown previously that the laticifer fluid of Calotropis procera (Ait.) R.Br. is highly toxic to the egg hatching and larval development of Aedes aegypti L. In the present study, the larvicidal potential of other laticifer fluids obtained from Cryptostegia grandiflora R.Br., Plumeria rubra L. and Euphorbia tirucalli L. was evaluated. We attempted to correlate larvicidal activity with the presence of endogenous proteolytic activity in the protein fraction of the fluids. After collection, the fluids were processed by centrifugation and dialysis to obtain the soluble laticifer protein (LP) fractions and eliminate water insoluble and low molecular mass molecules. LP did not visibly affect egg hatching at the doses assayed. LP from Cr. grandiflora exhibited the highest larval toxicity, while P. rubra was almost inactive. E. tirucalli was slightly active, but its activity could not be correlated to proteins since no protein was detected in the fluid. The larvicidal effects of LP from C. procera and Cr. grandiflora showed a significant relationship with the proteolytic activity of cysteine proteinases, which are present in both materials. A purified cysteine proteinase (papain) from the latex of Carica papaya (obtained from Sigma) was similarly effective, whereas trypsin and chymotrypsin (both serine proteinases) were ineffective. The results provide evidence for the involvement of cysteine proteinase activity in the larvicidal action of some laticifer fluids. C. procera is an invasive species found in areas infested with Ae. aegypti and thus could prove useful for combating mosquito proliferation. This is the first report to present evidence for the use of proteolytic enzymes as chemical agents to destroy Ae. aegypti larvae. PMID:19876551

  2. Endothelial Cell Permeability during Hantavirus Infection Involves Factor XII-Dependent Increased Activation of the Kallikrein-Kinin System

    PubMed Central

    Taylor, Shannon L.; Wahl-Jensen, Victoria; Copeland, Anna Maria; Jahrling, Peter B.; Schmaljohn, Connie S.

    2013-01-01

    Hemorrhagic fever with renal syndrome (HFRS) and hantavirus pulmonary syndrome (HPS) are diseases caused by hantavirus infections and are characterized by vascular leakage due to alterations of the endothelial barrier. Hantavirus-infected endothelial cells (EC) display no overt cytopathology; consequently, pathogenesis models have focused either on the influx of immune cells and release of cytokines or on increased degradation of the adherens junction protein, vascular endothelial (VE)-cadherin, due to hantavirus-mediated hypersensitization of EC to vascular endothelial growth factor (VEGF). To examine endothelial leakage in a relevant in vitro system, we co-cultured endothelial and vascular smooth muscle cells (vSMC) to generate capillary blood vessel-like structures. In contrast to results obtained in monolayers of cultured EC, we found that despite viral replication in both cell types as well as the presence of VEGF, infected in vitro vessels neither lost integrity nor displayed evidence of VE-cadherin degradation. Here, we present evidence for a novel mechanism of hantavirus-induced vascular leakage involving activation of the plasma kallikrein-kinin system (KKS). We show that incubation of factor XII (FXII), prekallikrein (PK), and high molecular weight kininogen (HK) plasma proteins with hantavirus-infected EC results in increased cleavage of HK, higher enzymatic activities of FXIIa/kallikrein (KAL) and increased liberation of bradykinin (BK). Measuring cell permeability in real-time using electric cell-substrate impedance sensing (ECIS), we identified dramatic increases in endothelial cell permeability after KKS activation and liberation of BK. Furthermore, the alterations in permeability could be prevented using inhibitors that directly block BK binding, the activity of FXIIa, or the activity of KAL. Lastly, FXII binding and autoactivation is increased on the surface of hantavirus-infected EC. These data are the first to demonstrate KKS activation during hantavirus infection and could have profound implications for treatment of hantavirus infections. PMID:23874198

  3. Histone chaperone ASF1 is involved in gene transcription activation in response to heat stress in Arabidopsis thaliana.

    PubMed

    Weng, Minjie; Yang, Yue; Feng, Haiyang; Pan, Zongde; Shen, Wen-Hui; Zhu, Yan; Dong, Aiwu

    2014-09-01

    ANTI-SILENCING FUNCTION 1 (ASF1) is an evolutionarily conserved histone chaperone involved in diverse chromatin-based processes in eukaryotes. Yet, its role in transcription and the underlying molecular mechanisms remain largely elusive, particularly in plants. Here, we show that the A?rabidopsis thaliana?ASF1 homologous genes, AtASF1A and AtASF1B, are involved in gene transcription activation in response to heat stress. The A?tasf1ab mutant displays defective basal as well as acquired thermotolerance phenotypes. Heat-induced expression of several key genes, including the HEAT SHOCK PROTEIN (HSP) genes Hsp101, Hsp70, Hsa32, Hsp17.6A and Hsp17.6B-CI, and the HEAT SHOCK FACTOR (HSF) gene HsfA2 but not HsfB1 is drastically impaired in Atasf1ab as compared with that in wild type. We found that AtASF1A/B proteins are recruited onto chromatin, and their enrichment is correlated with nucleosome removal and RNA polymerase II accumulation at the promoter and coding regions of HsfA2 and Hsa32 but not HsfB1. Moreover, AtASF1A/B facilitate H3K56 acetylation (H3K56ac), which is associated with HsfA2 and Hsa32 activation. Taken together, our study unravels an important function of AtASF1A/B in plant heat stress response and suggests that AtASF1A/B participate in transcription activation of some but not all HSF and HSP genes via nucleosome removal and H3K56ac stimulation. PMID:24548003

  4. Ras-related C3 botulinum toxin substrate 1 activation is involved in the pathogenesis of diabetic retinopathy

    PubMed Central

    LI, YANG-JUN; ZHANG, JIE; HAN, JING; DU, ZHAO-JIANG; WANG, PING; GUO, YONG

    2015-01-01

    This study used a streptozotocin (STZ)-induced rat model of diabetes to investigate whether Ras-related C3 botulinum toxin substrate 1 (Rac1) was involved in the pathogenesis of diabetic retinopathy. The effects of Rac1 inhibition on vascular endothelial (VE)-cadherin and ?-catenin expression in high glucose-induced rat retinal endothelial cells (RRECs) were additionally examined. Rac1 activation in the retinas from STZ-induced diabetic rats and in high glucose-induced RRECs was measured by reverse transcription-quantitative polymerase chain reaction analysis, immunohistochemistry and western blot analysis. The expression levels of VE-cadherin and ?-catenin were also examined with or without Rac1 inhibition through small interfering (si)RNA transfection. STZ-induced diabetes was associated with an increase in the vascular permeability of the retina. Furthermore, Rac1 activation was increased in the retina of STZ-induced diabetic rats and in high glucose-induced RRECs compared with that in the controls. Immunohistochemistry showed that immunostaining of Rac1 was localized in the outer plexiform, inner nuclear, inner plexiform and ganglion cell layers and in the retinal microvasculature of rats. The expression of ?-catenin was increased in the retinas of the diabetic rats at four, eight and 12 weeks after the induction of diabetes compared with that in the controls. Additionally, Rac1 activation was required for the high glucose-induced VE-cadherin expression decrease and for ?-catenin expression in high glucose-induced RRECs. Rac1 inhibition by Rac1-siRNA transfection effectively prevented hyperpermeability, ?-catenin expression and the VE-cadherin expression decrease in high glucose-induced RRECs. In conclusion, diabetes affects the expression of Rac1 in the retina. Rac1 may be involved in the diabetes-induced damage and/or alterations to the blood-retinal barrier through changes in VE-cadherin and ?-catenin expression. PMID:25452781

  5. Ras-related C3 botulinum toxin substrate 1 activation is involved in the pathogenesis of diabetic retinopathy.

    PubMed

    Li, Yang-Jun; Zhang, Jie; Han, Jing; DU, Zhao-Jiang; Wang, Ping; Guo, Yong

    2015-01-01

    This study used a streptozotocin (STZ)-induced rat model of diabetes to investigate whether Ras-related C3 botulinum toxin substrate 1 (Rac1) was involved in the pathogenesis of diabetic retinopathy. The effects of Rac1 inhibition on vascular endothelial (VE)-cadherin and ?-catenin expression in high glucose-induced rat retinal endothelial cells (RRECs) were additionally examined. Rac1 activation in the retinas from STZ-induced diabetic rats and in high glucose-induced RRECs was measured by reverse transcription-quantitative polymerase chain reaction analysis, immunohistochemistry and western blot analysis. The expression levels of VE-cadherin and ?-catenin were also examined with or without Rac1 inhibition through small interfering (si)RNA transfection. STZ-induced diabetes was associated with an increase in the vascular permeability of the retina. Furthermore, Rac1 activation was increased in the retina of STZ-induced diabetic rats and in high glucose-induced RRECs compared with that in the controls. Immunohistochemistry showed that immunostaining of Rac1 was localized in the outer plexiform, inner nuclear, inner plexiform and ganglion cell layers and in the retinal microvasculature of rats. The expression of ?-catenin was increased in the retinas of the diabetic rats at four, eight and 12 weeks after the induction of diabetes compared with that in the controls. Additionally, Rac1 activation was required for the high glucose-induced VE-cadherin expression decrease and for ?-catenin expression in high glucose-induced RRECs. Rac1 inhibition by Rac1-siRNA transfection effectively prevented hyperpermeability, ?-catenin expression and the VE-cadherin expression decrease in high glucose-induced RRECs. In conclusion, diabetes affects the expression of Rac1 in the retina. Rac1 may be involved in the diabetes-induced damage and/or alterations to the blood-retinal barrier through changes in VE-cadherin and ?-catenin expression. PMID:25452781

  6. Activation of STAT3 is involved in neuroprotection by electroacupuncture pretreatment via cannabinoid CB1 receptors in rats.

    PubMed

    Zhou, Heng; Zhang, Zhi; Wei, Haidong; Wang, Feng; Guo, Fan; Gao, Zijun; Marsicano, Giovanni; Wang, Qiang; Xiong, Lize

    2013-09-01

    Pretreatment with electroacupuncture (EA) attenuates cerebral ischemic injury through the endocannabinoid system, although the molecular mechanisms mediate this neuroprotection are unknown. It is well-known that signal transducer and activator of transcription 3 (STAT3) plays an essential role in cell survival and proliferation. Therefore, we investigated whether STAT3 is involved in EA pretreatment-induced neuroprotection via cannabinoid CB1 receptors (CB1R) after transient focal cerebral ischemia in rats. Two hours after EA pretreatment, focal cerebral ischemia was induced by middle cerebral artery occlusion (MACO) for 120 min. The expression of pSTAT3(Ser727), which is necessary for STAT3 activation, was examined in the ipsilateral ischemic penumbra. Infarct volumes and neurological scores were evaluated at 72 h after MACO in the presence or absence of the STAT3 inhibitor peptide (PpYLKTK). Neuronal apoptosis and the Bax/Bcl-2 ratio were also evaluated 24h after reperfusion. Our results showed that EA pretreatment significantly enhanced neuronal expression of pSTAT3(Ser727) in the ischemic penumbra 6h after reperfusion. Moreover, EA pretreatment reduced infarct volume, improved neurological outcome, inhibited neuronal apoptosis and decreased the Bax/Bcl-2 ratio following reperfusion. The beneficial effects of EA were attenuated by PpYLKTK administered 30 min before MACO, and PpYLKTK effectively reversed the increase in pSTAT3(Ser727) expression. Furthermore, CB1R antagonist or CB1R knockdown with siRNA blocked the elevation of pSTAT3(Ser727) expression by EA pretreatment, whereas the two CB1R agonists increased STAT3 activation. In conclusion, EA pretreatment enhances STAT3 activation via CB1R to protect against cerebral ischemia, suggesting that STAT3 activation may be a novel target for stroke intervention. PMID:23880371

  7. Corticotropin-releasing factor (CRF) receptor-1 is involved in cardiac noradrenergic activity observed during naloxone-precipitated morphine withdrawal

    PubMed Central

    Martínez-Laorden, Elena; García-Carmona, Juan-Antonio; Baroja-Mazo, Alberto; Romecín, Paola; Atucha, Noemí M; Milanés, María-Victoria; Laorden, María-Luisa

    2014-01-01

    Background and Purpose The negative affective states of withdrawal involve the recruitment of brain and peripheral stress circuitry [noradrenergic activity, induction of the hypothalamic–pituitary–adrenocortical (HPA) axis and activation of heat shock proteins (Hsps)]. Corticotropin-releasing factor (CRF) pathways are important mediators in the negative symptoms of opioid withdrawal. We performed a series of experiments to characterize the role of the CRF1 receptor in the response of stress systems to morphine withdrawal and its effect in the heart using genetically engineered mice lacking functional CRF1 receptors. Experimental Approach Wild-type and CRF1 receptor-knockout mice were treated with increasing doses of morphine. Precipitated withdrawal was induced by naloxone. Plasma adrenocorticotropic hormone (ACTH) and corticosterone levels, the expression of myocardial Hsp27, Hsp27 phosphorylated at Ser82, membrane (MB)- COMT, soluble (S)-COMT protein and NA turnover were evaluated by RIA, immunoblotting and HPLC. Key Results During morphine withdrawal we observed an enhancement of NA turnover in parallel with an increase in mean arterial blood pressure (MAP) and heart rate (HR) in wild-type mice. In addition, naloxone-precipitated morphine withdrawal induced an activation of HPA axis and Hsp27. The principal finding of the present study was that plasma ACTH and corticosterone levels, MB-COMT, S-COMT, NA turnover, and Hsp27 expression and activation observed during morphine withdrawal were significantly inhibited in the CRF1 receptor-knockout mice. Conclusion and Implications Our results demonstrate that CRF/CRF1 receptor activation may contribute to stress-induced cardiovascular dysfunction after naloxone-precipitated morphine withdrawal and suggest that CRF/CRF1 receptor pathways could contribute to cardiovascular disease associated with opioid addiction. PMID:24490859

  8. Antimicrobial activity of plant essential oils against bacterial and fungal species involved in food poisoning and/or food decay.

    PubMed

    Lixandru, Brîndu?a-Elena; Dr?cea, Nicoleta Olgu?a; Dragomirescu, Cristiana Cerasella; Dr?gulescu, Elena Carmina; Coldea, Ileana Lumini?a; Anton, Liliana; Dobre, Elena; Rovinaru, Camelia; Codi??, Irina

    2010-01-01

    The currative properties of aromatic and medicinal plants have been recognized since ancient times and, more recently, the antimicrobial activity of plant essential oils has been used in several applications, including food preservation. The purpose of this study was to create directly comparable, quantitative data on the antimicrobial activity of some plant essential oils prepared in the National Institute of Research-Development for Chemistry and Petrochemistry, Bucharest to be used for the further development of food packaging technology, based on their antibacterial and antifungal activity. The essential oils extracted from thyme (Thymus vulgaris L.), basil (Ocimum basilicum L.), coriander (Coriandrum sativum L.), rosemary (Rosmarinus officinalis L.), sage (Salvia officinalis L.), fennel (Foeniculum vulgare L.), spearmint (Mentha spicata L.) and carraway (Carum carvi L.) were investigated for their antimicrobial activity against eleven different bacterial and three fungal strains belonging to species reported to be involved in food poisoning and/or food decay: S. aureus ATCC 25923, S. aureus ATCC 6538, S. aureus ATCC 25913, E. coli ATCC 25922, E. coli ATCC 35218, Salmonella enterica serovar Enteritidis Cantacuzino Institute Culture Collection (CICC) 10878, Listeria monocytogenes ATCC 19112, Bacillus cereus CIP 5127, Bacillus cereus ATCC 11778, Candida albicans ATCC 10231, Aspergillus niger ATCC 16404, Penicillium spp. CICC 251 and two E. coli and Salmonella enterica serovar Enteritidis clinical isolates. The majority of the tested essential oils exibited considerable inhibitory capacity against all the organisms tested, as supported by growth inhibition zone diameters, MICs and MBC's. Thyme, coriander and basil oils proved the best antibacterial activity, while thyme and spearmint oils better inhibited the fungal species. PMID:21462837

  9. Locomotor activation by theacrine, a purine alkaloid structurally similar to caffeine: involvement of adenosine and dopamine receptors.

    PubMed

    Feduccia, Allison A; Wang, Yuanyuan; Simms, Jeffrey A; Yi, Henry Y; Li, Rui; Bjeldanes, Leonard; Ye, Chuangxing; Bartlett, Selena E

    2012-08-01

    Purine compounds, such as caffeine, have many health-promoting properties and have proven to be beneficial in treating a number of different conditions. Theacrine, a purine alkaloid structurally similar to caffeine and abundantly present in Camellia kucha, has recently become of interest as a potential therapeutic compound. In the present study, theacrine was tested using a rodent behavioral model to investigate the effects of the drug on locomotor activity. Long Evans rats were injected with theacrine (24 or 48 mg/kg, i.p.) and activity levels were measured. Results showed that the highest dose of theacrine (48 mg/kg, i.p.) significantly increased locomotor activity compared to control animals and activity remained elevated throughout the duration of the session. To test for the involvement of adenosine receptors underlying theacrine's motor-activating properties, rats were administered a cocktail of the adenosine A? agonist, N?-cyclopentyladenosine (CPA; 0.1 mg/kg, i.p.) and A(2A) receptor agonist 2-p-(2-carboxyethyl)phenethylamino-5'-N-ethylcarboxamidoadenosine (CGS-21680; 0.2 mg/kg, i.p.). Pre-treatment with theacrine significantly attenuated the motor depression induced by the adenosine receptor agonists, indicating that theacrine is likely acting as an adenosine receptor antagonist. Next, we examined the role of DA D? and D? receptor antagonism on theacrine-induced hyperlocomotion. Both antagonists, D?R SCH23390 (0.1 or 0.05 mg/kg, i.p.) and D?R eticlopride (0.1 mg/kg, i.p.), significantly reduced theacrine-stimulated activity indicating that this behavioral response, at least in part, is mediated by DA receptors. In order to investigate the brain region where theacrine may be acting, the drug (10 or 20 ?g) was infused bilaterally into nucleus accumbens (NAc). Theacrine enhanced activity levels in a dose-dependent manner, implicating a role of the NAc in modulating theacrine's effects on locomotion. In addition, theacrine did not induce locomotor sensitization or tolerance after chronic exposure. Taken together, these findings demonstrate that theacrine significantly enhances activity; an effect which is mediated by both the adenosinergic and dopaminergic systems. PMID:22579816

  10. A zebrafish (Danio rerio) bloodthirsty member 20 with E3 ubiquitin ligase activity involved in immune response against bacterial infection.

    PubMed

    Zhang, Xinshang; Zhao, Heng; Chen, Yeyu; Luo, Huiying; Yang, Peilong; Yao, Bin

    2015-01-30

    The tripartite motif (TRIM)-containing proteins exhibit various activities and play important roles in the immune system through regulating signaling pathways. Bloodthirsty gene is a multigene subset of TRIM genes. In this study we identified and characterized a new member of the bloodthirsty subset of TRIM genes, btr20, in zebrafish (Danio rerio). The gene is located on chromosome 19 and forms a cluster with btr18, btr21, btr22 and an E3 ubiquitin ligase TRIM39-like gene. Deduced btr20 represents a RBCC-B30.2 TRIM protein containing 544 amino acids. The mRNA expression level of btr20 was highest in intestine and gill, followed by in spleen and kidney. Challenge experiment with Aeromonas hydrophila strain NJ-1 showed that the levels of btr20 and NF-?B mRNA were remarkably upregulated in the four tissues mentioned above. btr20 was localized in the cytoplasm and formed aggregate in human embryonic kidney cell line 293T. In vitro self-ubiquitylation experiment demonstrated that btr20 has E3 ubiquitin ligase activity that can be self-ubiquitylated with most E2 enzymes, especially UbcH6. The results suggested that btr20 may involve in the anti-microbial activity in the immune system as an E3 ubiquitin ligase. PMID:25542153

  11. Possible Involvement of TLRs and Hemichannels in Stress-Induced CNS Dysfunction via Mastocytes, and Glia Activation

    PubMed Central

    Aguirre, Adam; Maturana, Carola J.; Harcha, Paloma A.; Sáez, Juan C.

    2013-01-01

    In the central nervous system (CNS), mastocytes and glial cells (microglia, astrocytes and oligodendrocytes) function as sensors of neuroinflammatory conditions, responding to stress triggers or becoming sensitized to subsequent proinflammatory challenges. The corticotropin-releasing hormone and glucocorticoids are critical players in stress-induced mastocyte degranulation and potentiation of glial inflammatory responses, respectively. Mastocytes and glial cells express different toll-like receptor (TLR) family members, and their activation via proinflammatory molecules can increase the expression of connexin hemichannels and pannexin channels in glial cells. These membrane pores are oligohexamers of the corresponding protein subunits located in the cell surface. They allow ATP release and Ca2+ influx, which are two important elements of inflammation. Consequently, activated microglia and astrocytes release ATP and glutamate, affecting myelinization, neuronal development, and survival. Binding of ligands to TLRs induces a cascade of intracellular events leading to activation of several transcription factors that regulate the expression of many genes involved in inflammation. During pregnancy, the previous responses promoted by viral infections and other proinflammatory conditions are common and might predispose the offspring to develop psychiatric disorders and neurological diseases. Such disorders could eventually be potentiated by stress and might be part of the etiopathogenesis of CNS dysfunctions including autism spectrum disorders and schizophrenia. PMID:23935250

  12. Retinal cell death induced by TRPV1 activation involves NMDA signaling and upregulation of nitric oxide synthases.

    PubMed

    Leonelli, Mauro; Martins, Daniel O; Britto, Luiz R G

    2013-04-01

    The activation of the transient receptor potential vanilloid type 1 channel (TRPV1) has been correlated with oxidative and nitrosative stress and cell death in the nervous system. Our previous results indicate that TRPV1 activation in the adult retina can lead to constitutive and inducible nitric oxide synthase-dependent protein nitration and apoptosis. In this report, we have investigated the potential effects of TRPV1 channel activation on nitric oxide synthase (NOS) expression and function, and the putative participation of ionotropic glutamate receptors in retinal TRPV1-induced protein nitration, lipid peroxidation, and DNA fragmentation. Intravitreal injections of the classical TRPV1 agonist capsaicin up-regulated the protein expression of the inducible and endothelial NOS isoforms. Using 4,5-diaminofluorescein diacetate for nitric oxide (NO) imaging, we found that capsaicin also increased the production of NO in retinal blood vessels. Processes and perikarya of TRPV1-expressing neurons in the inner nuclear layer of the retina were found in the vicinity of nNOS-positive neurons, but those two proteins did not colocalize. Retinal explants exposed to capsaicin presented high protein nitration, lipid peroxidation, and cell death, which were observed in the inner nuclear and plexiform layers and in ganglion cells. This effect was partially blocked by AP-5, a NMDA glutamate receptor antagonist, but not by CNQX, an AMPA/kainate receptor antagonist. These data support a potential role for TRPV1 channels in physiopathological retinal processes mediated by NO, which at least in part involve glutamate release. PMID:23324998

  13. The Department of Kinesiology and Physical Education offers courses in theoretical perspectives of the study of human movement and the practical application of physical activity involvement. A

    E-print Network

    Seldin, Jonathan P.

    of the study of human movement and the practical application of physical activity involvement. A multidisciplinary field, Kinesiology provides students with a broad perspective for studying physical activity complete physical activity courses as part of their program.The B.A. (Kinesiology) degree program offers

  14. The Department of Physical Education (PE) offers courses in the study of human movement and physical activity involvement. The Department's curriculum is designed to provide students with a

    E-print Network

    Seldin, Jonathan P.

    and physical activity involvement. The Department's curriculum is designed to provide students with a broad-public organizations with a physical activity focus (YMCA,racquet clubs,etc.),sports administration,sports facility Education plus 6 Physical Activity). A maximum of 20 Physical Education courses (60.0 credit hours

  15. A molecular signature of tissues with pacemaker activity in the heart and upper urinary tract involves coexpressed hyperpolarization-activated cation and T-type Ca2+ channels

    PubMed Central

    Hurtado, Romulo; Bub, Gil; Herzlinger, Doris

    2014-01-01

    Renal pacemakers set the origin and frequency of the smooth muscle contractions that propel wastes from the kidney to the bladder. Although congenital defects impairing this peristalsis are a leading cause of pediatric renal failure, the mechanisms underlying renal pacemaker activity remain unknown. Using ratiometric optical mapping and video microscopy, we discovered that hyperpolarization-activated cation (HCN) channel block with the specific anatagonist ZD7288 (30 ?m; IC50) abolished the pacemaker depolarizations that initiate murine upper urinary tract peristalsis. Optical mapping and immunohistochemistry indicate that pacemaker potentials are generated by cells expressing HCN isoform-3, and that HCN3+ cells are coupled to definitive smooth muscle via gap junctions. Furthermore, we demonstrate that HCN3+ cells coexpress T-type Ca2+ (TTC) channels and that TTC channel inhibition with R(?)efonidipine or NNC55-0396 decreased contractile frequency in a dose-dependent manner. Collectively, these data demonstrate that HCN3+/TTC+ cells are the pacemakers that set the origin and rate of upper urinary tract peristalsis. These results reveal a conserved mechanism controlling autorhythmicity in 2 distinct muscle types, as HCN and TTC channels also mediate cardiac pacemaker activity. Moreover, these findings have translational applications, including the development of novel diagnostics to detect fetal urinary tract motility defects prior to renal damage.—Hurtado, R., Bub, G., Herzlinger, D. A molecular signature of tissues with pacemaker activity in the heart and upper urinary tract involves coexpressed hyperpolarization-activated cation and T-type Ca2+ channels. PMID:24189942

  16. The structural changes of the bagasse hemicelluloses during the cooking process involving active oxygen and solid alkali.

    PubMed

    Shi, Jian-Bin; Yang, Qiu-Lin; Lin, Lu; Zhuang, Jun-Ping; Pang, Chun-Sheng; Xie, Tu-Jun; Liu, Ying

    2012-10-01

    This work describes the structural changes of bagasse hemicelluloses during the cooking process involving active oxygen (O(2) and H(2)O(2)) and solid alkali (MgO). The hemicelluloses obtained from the bagasse raw material, pulp, and yellow liquor were analyzed by high-performance anion-exchange chromatography (HPAEC), gel permeation chromatography (GPC), Fourier transform infrared spectroscopy (FT-IR), and (1)H-(13)C 2D hetero-nuclear single quantum coherence spectroscopy (HSQC). The results revealed that the structure of the bagasse hemicelluloses was L-arabino-(4-O-methylglucurono)-D-xylan. Some sugar units in hemicelluloses were oxidized under the cooking conditions. Additionally, the backbones and the ester linkages of hemicelluloses were heavily cleaved during the cooking process. PMID:22925766

  17. Involvement of lipid peroxidation, oncogene expression and induction of apoptosis in the antitumorous activity of ferric-sorbitol-citrate.

    PubMed

    Poljak-Blazi, M; Kralj, M; Hadzija, M P; Zarkovi?, N; Zarkovi?, K; Waeg, G

    2000-06-01

    We described before that iron-containing, anti-anaemic drug, ferric-sorbitol-citrate complex (FSC) inhibited proliferation of various murine cancer cells in vitro and caused tumour regression in vivo, but did not affect proliferation of the non-malignant cells. The aim of this study was to evaluate further the anticancer activity mechanism of FSC using human colon cancer cell line CaCo2. After treatment with FSC for 72 hours impaired proliferative ability and viability of CaCo2 cells as observed. Growth modification caused by FSC involved diminished expression of Bcl-2, and over-expression of mp53 proto-oncogenes, accompanied by increased incidence of apoptosis. Immunostaining the cells applying monoclonal antibodies for lipid peroxidation product 4-hydroxynonenal (HNE) showed that FSC-iron increased intracellular HNE, but did not induce severe HNE-mediated oxidative stress. Thus, antitumorous mechanism of FSC involves modulation of oncogene expression and induction of apoptosis apparently not triggered by lipid peroxidation-mediated oxidative stress, although FSC might restore endogenous HNE production in the CaCo2 cells to level resembling physiological for various non-malignant cells and tissues. Higher dose of FSC increased also number of intracellular ferritin positive CaCo2 cells. PMID:10941536

  18. Effect of game format on heart rate, activity profile, and player involvement in elite and recreational youth players.

    PubMed

    Randers, M B; Andersen, T B; Rasmussen, L S; Larsen, M N; Krustrup, P

    2014-08-01

    The purpose of this study was to evaluate activity profile, aerobic load, and player involvement in two game formats of recreational and elite youth football for two age groups. A total of 152 youth players participated, with 45 U10 players playing 5v5 and 8v8 games, and 41 U13 players playing 8v8 and 11v11 (20 min) games. Activity profile, heart rate (HR), and technical actions were measured during all games using 10 Hz GPS, video filming, and HR monitors. For U10, no difference was found in total distance covered (1754 ± 237 vs 1771 ± 314 m, P = 0.650, d = 0.06), whereas mean HR (174 ± 10 vs 168 ± 12 bpm, P = 0.001, d = 0.59) and number of technical actions (65.1 ± 24.0 vs 36.9 ± 20.4, P? ? 0.001, d = 1.27) were higher in 5v5 than in 8v8. For U13, lower total distance covered (1821 ± 325 vs 2038 ± 328 m, P < 0.001, d = 0.66) and higher number of technical actions (36.2 ± 14.9 vs 26.9 ± 14.1, P < 0.001, d = 0.64) were observed in 8v8 than in 11v11, with no difference in mean HR (170 ± 10 vs 171 ± 10 bpm, P = 0.679, d = 0.10). In conclusion, HR is high in youth football matches irrespective of the level of play and the game format. Playing with fewer players on smaller pitches results in minor changes to the physical loading but elevates the technical involvement of youth players both at elite level and recreational level. PMID:24944130

  19. Telomerase activity-independent function of telomerase reverse transcriptase is involved in acrylamide-induced neuron damage.

    PubMed

    Zhang, P; Pan, H; Wang, J; Liu, X; Hu, X

    2014-07-01

    Polyacrylamide is used widely in industry, and its decomposition product, acrylamide (ACR), readily finds its way into commonly consumed cosmetics and baked and fried foods. ACR exerts potent neurotoxic effects in human and animal models. Telomerase reverse transcriptase (TERT), the catalytic subunit of telomerase, traditionally has been considered to play an important role in maintaining telomere length. Emerging evidence has shown, however, that TERT plays an important role in neuroprotection by inhibiting apoptosis and excitotoxicity, and by promoting angiogenesis, neuronal survival and neurogenesis, which are closely related to the telomere-independent functions of TERT. We investigated whether and how the TERT pathway is involved in ACR induced neurotoxicity in rat cortical neurons. We found that ACR 1) significantly reduced the viability of cortical neurons as measured by MTT assay, 2) induced neuron apoptosis as revealed by FITC-conjugated Annexin V/PI double staining and flow cytometry (FACS) analysis, 3) elevated expression of cleaved caspase-3, and 4) decreased bcl-2 expression of cortical neurons. ACR also increased intracellular ROS levels in cortical neurons, increased MDA levels and reduced GSH, SOD and GSH-Px levels in mitochondria in a dose-dependent manner. We found that TERT expression in mitochondria was increased by ACR at concentrations of 2.5 and 5.0 mM, but TERT expression was decreased by 10 mM ACR. Telomerase activity, however, was undetectable in rat cortical neurons. Our results suggest that the TERT pathway is involved in ACR induced apoptosis of cortical neurons. TERT also may exert its neuroprotective role in a telomerase activity-independent way, especially in mitochondria. PMID:24279610

  20. Involvement of Dopamine Receptors in Binge Methamphetamine-Induced Activation of Endoplasmic Reticulum and Mitochondrial Stress Pathways

    PubMed Central

    Beauvais, Genevieve; Atwell, Kenisha; Jayanthi, Subramaniam; Ladenheim, Bruce; Cadet, Jean Lud

    2011-01-01

    Single large doses of methamphetamine (METH) cause endoplasmic reticulum (ER) stress and mitochondrial dysfunctions in rodent striata. The dopamine D1 receptor appears to be involved in these METH-mediated stresses. The purpose of this study was to investigate if dopamine D1 and D2 receptors are involved in ER and mitochondrial stresses caused by single-day METH binges in the rat striatum. Male Sprague-Dawley rats received 4 injections of 10 mg/kg of METH alone or in combination with a putative D1 or D2 receptor antagonist, SCH23390 or raclopride, respectively, given 30 min prior to each METH injection. Rats were euthanized at various timepoints afterwards. Striatal tissues were used in quantitative RT-PCR and western blot analyses. We found that binge METH injections caused increased expression of the pro-survival genes, BiP/GRP-78 and P58IPK, in a SCH23390-sensitive manner. METH also caused up-regulation of ER-stress genes, Atf2, Atf3, Atf4, CHOP/Gadd153 and Gadd34. The expression of heat shock proteins (HSPs) was increased after METH injections. SCH23390 completely blocked induction in all analyzed ER stress-related proteins that included ATF3, ATF4, CHOP/Gadd153, HSPs and caspase-12. The dopamine D2-like antagonist, raclopride, exerted small to moderate inhibitory influence on some METH-induced changes in ER stress proteins. Importantly, METH caused decreases in the mitochondrial anti-apoptotic protein, Bcl-2, but increases in the pro-apoptotic proteins, Bax, Bad and cytochrome c, in a SCH23390-sensitive fashion. In contrast, raclopride provided only small inhibition of METH-induced changes in mitochondrial proteins. These findings indicate that METH-induced activation of striatal ER and mitochondrial stress pathways might be more related to activation of SCH23390-sensitive receptors. PMID:22174933

  1. BcSAK1, a Stress-Activated Mitogen-Activated Protein Kinase, Is Involved in Vegetative Differentiation and Pathogenicity in Botrytis cinerea?

    PubMed Central

    Segmüller, Nadja; Ellendorf, Ursula; Tudzynski, Bettina; Tudzynski, Paul

    2007-01-01

    The gene bcsak1, encoding a mitogen-activated protein kinase (MAPK) of Botrytis cinerea, was cloned and characterized. The protein has high homology to the yeast Hog1 and to corresponding MAPKs from filamentous fungi, but it shows unique functional features. The protein is phosphorylated under osmotic stress, specific fungicides, and oxidative stress mediated by H2O2 and menadione. Northern blot analyses indicate that only a subset of typical oxidative stress response genes is regulated by BcSAK1. In contrast to most other fungal systems, ?bcsak1 mutants are significantly impaired in vegetative and pathogenic development: they are blocked in conidia formation, show increased sclerotial development, and are unable to penetrate unwounded plant tissue. These data indicate that in B. cinerea the stress-activated MAPK cascade is involved in essential differentiation programs. PMID:17189492

  2. BcSAK1, a stress-activated mitogen-activated protein kinase, is involved in vegetative differentiation and pathogenicity in Botrytis cinerea.

    PubMed

    Segmüller, Nadja; Ellendorf, Ursula; Tudzynski, Bettina; Tudzynski, Paul

    2007-02-01

    The gene bcsak1, encoding a mitogen-activated protein kinase (MAPK) of Botrytis cinerea, was cloned and characterized. The protein has high homology to the yeast Hog1 and to corresponding MAPKs from filamentous fungi, but it shows unique functional features. The protein is phosphorylated under osmotic stress, specific fungicides, and oxidative stress mediated by H(2)O(2) and menadione. Northern blot analyses indicate that only a subset of typical oxidative stress response genes is regulated by BcSAK1. In contrast to most other fungal systems, Deltabcsak1 mutants are significantly impaired in vegetative and pathogenic development: they are blocked in conidia formation, show increased sclerotial development, and are unable to penetrate unwounded plant tissue. These data indicate that in B. cinerea the stress-activated MAPK cascade is involved in essential differentiation programs. PMID:17189492

  3. Analysis of Cathepsin and Furin Proteolytic Enzymes Involved in Viral Fusion Protein Activation in Cells of the Bat Reservoir Host

    PubMed Central

    El Najjar, Farah; Lampe, Levi; Baker, Michelle L.; Wang, Lin-Fa; Dutch, Rebecca Ellis

    2015-01-01

    Bats of different species play a major role in the emergence and transmission of highly pathogenic viruses including Ebola virus, SARS-like coronavirus and the henipaviruses. These viruses require proteolytic activation of surface envelope glycoproteins needed for entry, and cellular cathepsins have been shown to be involved in proteolysis of glycoproteins from these distinct virus families. Very little is currently known about the available proteases in bats. To determine whether the utilization of cathepsins by bat-borne viruses is related to the nature of proteases in their natural hosts, we examined proteolytic processing of several viral fusion proteins in cells derived from two fruit bat species, Pteropus alecto and Rousettus aegyptiacus. Our work shows that fruit bat cells have homologs of cathepsin and furin proteases capable of cleaving and activating both the cathepsin-dependent Hendra virus F and the furin-dependent parainfluenza virus 5 F proteins. Sequence analysis comparing Pteropus alecto furin and cathepsin L to proteases from other mammalian species showed a high degree of conservation; however significant amino acid variation occurs at the C-terminus of Pteropus alecto furin. Further analysis of furin-like proteases from fruit bats revealed that these proteases are catalytically active and resemble other mammalian furins in their response to a potent furin inhibitor. However, kinetic analysis suggests that differences may exist in the cellular localization of furin between different species. Collectively, these results indicate that the unusual role of cathepsin proteases in the life cycle of bat-borne viruses is not due to the lack of active furin-like proteases in these natural reservoir species; however, differences may exist between furin proteases present in fruit bats compared to furins in other mammalian species, and these differences may impact protease usage for viral glycoprotein processing. PMID:25706132

  4. Domains with transcriptional regulatory activity within the ALL1 and AF4 proteins involved in acute leukemia.

    PubMed Central

    Prasad, R; Yano, T; Sorio, C; Nakamura, T; Rallapalli, R; Gu, Y; Leshkowitz, D; Croce, C M; Canaani, E

    1995-01-01

    The ALLI gene, located at chromosome band 11q23, is involved in acute leukemia through a series of chromosome translocations and fusion to a variety of genes, most frequently to A4 and AF9. The fused genes encode chimeric proteins proteins. Because the Drosophila homologue of ALL1, trithorax, is a positive regulator of homeotic genes and acts at the level of transcription, it is conceivable that alterations in ALL1 transcriptional activity may underlie its action in malignant transformation. To begin studying this, we examined the All1, AF4, AF9, and AF17 proteins for the presence of potential transcriptional regulatory domains. This was done by fusing regions of the proteins to the yeast GAL4 DNA binding domain and assaying their effect on transcription of a reporter gene. A domain of 55 residues positioned at amino acids 2829-2883 of ALL1 was identified as a very strong activator. Further analysis of this domain by in vitro mutagenesis pointed to a core of hydrophobic and acidic residues as critical for the activity. An ALL1 domain that repressed transcription of the reporter gene coincided with the sequence homologous to a segment of DNA methyltransferase. An AF4 polypeptide containing residues 480-560 showed strong activation potential. The C-terminal segment of AF9 spanning amino acids 478-568 transactivated transcription of the reporter gene in HeLa but not in NIH 3T3 cells. These results suggest that ALL1, AF4, and probably AF9 interact with the transcriptional machinery of the cell. Images Fig. 1 Fig. 4 Fig. 5 PMID:8618864

  5. Involvement of the monoaminergic system in the antidepressant-like activity of chromium chloride in the forced swim test.

    PubMed

    Piotrowska, A; Siwek, A; Wolak, M; Pochwat, B; Szewczyk, B; Opoka, W; Poleszak, E; Nowak, G

    2013-08-01

    Bio-metal chromium(III) is a crucial microelement for the proper functioning of living organisms. Previous preclinical and clinical studies reported its potential antidepressant properties. The aim of the present study was to examine the effect of antidepressants and noradrenergic and dopaminergic receptor antagonists on chromium chloride (CrCl?) activity in the forced swim test (FST) in mice and rats. Imipramine (5 mg/kg), fluoxetine (5 mg/kg) and reboxetine (5 mg/kg) but not bupropion (1 mg/kg), administered jointly with CrCl? at a dose of 6 mg/kg, reduced the immobility time in the FST in mice. The reduction of the immobility time induced by the active dose (12 mg/kg) of CrCl? was completely abolished by propranolol (2 mg/kg, ?-adrenoceptor antagonist), SCH 23390 (0.5 mg/kg, a dopamine D? receptor antagonist), and partially by prazosin (1 mg/kg, an ??-adrenoceptor antagonist), yohimbine (1 mg/kg, an ??-adrenoceptor antagonist) and sulpiryd (50 mg/kg, a dopamine D?/D? receptor antagonist) administration. The locomotor activity was significantly reduced by CrCl? + reboxetine treatment, which did not influence the reboxetine enhancement of the antidepressant-like effect of CrCl? in the FST. Moreover, CrCl? at a dose of 32 mg/kg (although not at 12 mg/kg) significantly reduced the immobility and enhanced the climbing (but not swimming) time in the FST in rats, which indicates the involvement of the noradrenergic pathway in this effect. The present study indicates that the antidepressant-like activity of chromium in the FST is dependent (although to a different extent) on the noradrenergic, dopaminergic and serotonin systems. PMID:24101396

  6. JNK pathway is involved in the inhibition of inflammatory target gene expression and NF-kappaB activation by melittin

    PubMed Central

    Park, Hye Ji; Lee, Hwa Jeong; Choi, Myung Sook; Son, Dong Ju; Song, Ho Sueb; Song, Min Jong; Lee, Jeong Min; Han, Sang Bae; Kim, Youngsoo; Hong, Jin Tae

    2008-01-01

    Background Bee venom therapy has been used to treat inflammatory diseases including rheumatoid arthritis in humans and in experimental animals. We previously found that bee venom and melittin (a major component of bee venom) have anti-inflammatory effect by reacting with the sulfhydryl group of p50 of nuclear factor-kappa B (NF-?B) and I?B kinases (IKKs). Since mitogen activated protein (MAP) kinase family is implicated in the NF-?B activation and inflammatory reaction, we further investigated whether activation of MAP kinase may be also involved in the anti-inflammatory effect of melittin and bee venom. Methods The anti-inflammatory effects of melittin and bee venom were investigated in cultured Raw 264.7 cells, THP-1 human monocytic cells and Synoviocytes. The activation of NF-?B was investigated by electrophoretic mobility shift assay. Nitric oxide (NO) and prostaglandin E2 (PGE2) were determined either by Enzyme Linked Immuno Sorbent Assay or by biochemical assay. Expression of I?B, p50, p65, inducible nitric oxide synthetase (iNOS), cyclooxygenase-2 (COX-2) as well as phosphorylation of MAP kinase family was determined by Western blot. Results Melittin (0.5–5 ?g/ml) and bee venom (5 and 10 ?g/ml) inhibited lipopolysaccharide (LPS, 1 ?g/ml) and sodium nitroprusside (SNP, 200 ?M)-induced activation of c-Jun NH2-terminal kinase (JNK) in RAW 264.7 cells in a dose dependent manner. However, JNK inhibitor, anthra [1,9-cd]pyrazole-6 (2H)-one (SP600215, 10–50 ?M) dose dependently suppressed the inhibitory effects of melittin and bee venom on NF-?B dependent luciferase and DNA binding activity via suppression of the inhibitory effect of melittin and bee venom on the LPS and SNP-induced translocation of p65 and p50 into nucleus as well as cytosolic release of I?B. Moreover, JNK inhibitor suppressed the inhibitory effects of melittin and bee venom on iNOS and COX-2 expression, and on NO and PGE2 generation. Conclusion These data show that melittin and bee venom prevent LPS and SNP-induced NO and PGE2 production via JNK pathway dependent inactivation of NF-?B, and suggest that inactivation of JNK pathways may also contribute to the anti-inflammatory and anti-arthritis effects of melittin and bee venom. PMID:18507870

  7. Community Effects on Teacher Involvement in School Development Activity: A Study of Teachers in Cities, Smaller Towns and Rural Areas in Norway.

    ERIC Educational Resources Information Center

    Midthassel, Unni Vere; Manger, Terje; Torsheim, Torbjorn

    2002-01-01

    Examined the effects of community type on teacher involvement in school development activity (SDA). Data on urban, small town, and rural teachers indicated that teachers in smaller towns were more involved in SDA than those in rural areas, while the differences between cities and smaller towns were not statistically significant. The impact of…

  8. Thyroid-stimulating hormone and cyclic AMP activate p38 mitogen-activated protein kinase cascade. Involvement of protein kinase A, rac1, and reactive oxygen species.

    PubMed

    Pomerance, M; Abdullah, H B; Kamerji, S; Correze, C; Blondeau, J P

    2000-12-22

    p38 mitogen-activated protein kinases (p38-MAPKs) are activated by cytokines, cellular stresses, growth factors, and hormones. We show here that p38-MAPKs are activated upon stimulation by thyroid-stimulating hormone (TSH) or cAMP. TSH caused the phosphorylation of p38-MAPK in Chinese hamster ovary cells stably transfected with the human TSH receptor but not in wild-type Chinese hamster ovary cells. The effect of TSH was fully mimicked by the adenylyl cyclase activator, forskolin, and by a permeant analog of cAMP. The effect of forskolin was reproduced in FRTL5 rat thyroid cells. TSH also stimulated the phosphorylation of MAPK kinase 3 or 6, over the same time scale as that of p38-MAPKs. TSH and forskolin stimulated the activity of the alpha-isoform of p38-MAPK assayed by phosphorylation of the transcription factor ATF2. The activity of MAPK-activated protein kinase-2 was stimulated by TSH and forskolin. This stimulation was abolished by SB203580, a specific inhibitor of p38-MAPKs. The protein kinase A inhibitor H89 inhibited the stimulation of phosphorylation of p38-MAPKs by forskolin, whereas inhibitors of protein kinase C, p70(S6k), and phosphatidylinositol 3-kinase were ineffective. Expression of the dominant negative form of Rac1, but not that of Ras, blocked forskolin-induced p38-MAPK activation. Diphenylene iodonium, a potent inhibitor of NADPH oxidase(s), and ascorbic acid, an effective free radical scavenger, suppressed TSH- or forskolin-stimulated p38-MAPK phosphorylation, indicating that the generation of reactive oxygen species plays a key role in signaling from cAMP to p38-MAPKs. Inhibition of the p38-MAPK pathway with SB203580 partially but significantly, attenuates cAMP- and TSH-induced expression of the sodium iodide symporter in FRTL-5 cells. These results point to a new signaling pathway for the G(s)-coupled TSH receptor, involving cAMP, protein kinase A, Rac1, and reactive oxygen species and resulting in the activation of a signaling kinase cascade that includes MAPK kinase 3 or 6, p38-MAPK, and MAPK-activated protein kinase-2. PMID:11006268

  9. OsSLI1, a Homeodomain Containing Transcription Activator, Involves Abscisic Acid Related Stress Response in Rice (Oryza sativa L.)

    PubMed Central

    Liao, Jiakai; Yuan, Xi; Chen, Hui; Zhang, Hong-Sheng

    2014-01-01

    Homeodomain-leucine zipper type I (HD-Zip I) proteins are involved in the regulation of plant development and response to environmental stresses. In this study, OsSLI1 (Oryza sativa stress largely induced 1), encoding a member of the HD-Zip I subfamily, was isolated from rice. The expression of OsSLI1 was dramatically induced by multiple abiotic stresses and exogenous abscisic acid (ABA). In silico sequence analysis discovered several cis-acting elements including multiple ABREs (ABA-responsive element binding factors) in the upstream promoter region of OsSLI1. The OsSLI1-GFP fusion protein was localized in the nucleus of rice protoplast cells and the transcriptional activity of OsSLI1 was confirmed by the yeast hybrid system. Further, it was found that OsSLI1 expression was enhanced in an ABI5-Like1 (ABL1) deficiency rice mutant abl1 under stress conditions, suggesting that ABL1 probably negatively regulates OsSLI1 gene expression. Moreover, it was found that OsSLI1 was regulated in panicle development. Taken together, OsSLI1 may be a transcriptional activator regulating stress-responsive gene expression and panicle development in rice. PMID:25089296

  10. The practice of effective involvment of Master and Graduate students to research activity for space science and technology.

    NASA Astrophysics Data System (ADS)

    Zelenyi, Lev; Alferov, A.; Zeleniy, Lev; Veselov, M.; Rodin, V.

    One of serious problems both for fundamental space research and various applied fields of space exploration is an effective involvement of graduates to real scientific or engineering work. The basic education even of high quality does not prepare a graduate well enough to start productive work in such specific fields as space science and engineering. An idea to organize the thematic educational training with elements of participation in real projects based on a profile research of Academic and industry organizations already at Master's degree program level was successfully implemented in Russian Academy in cooperation with Moscow Institute of Physics and Technology. However at present, under severe competition with commercial companies, we need to search for new additional ways to intensify young talented people inflow to the field of space science and applications. Various activities aimed to resolve this problem are now conducted by Russian Space Science Council and Russian Academy of Sciences, such as educational discourses for high-schools and students of junior level. We discuss the first results of this practice. Very important part of this activity is development of effective integration into international educational and outreach programs. The report is prepared in a frame of "Young Scientists Support Program" of Russian Academy of Sciences.

  11. Microarray Analysis of Genes Involved with Shell Strength in Layer Shell Gland at the Early Stage of Active Calcification

    PubMed Central

    Liu, Zhangguo; Zheng, Qi; Zhang, Xueyu; Lu, Lizhi

    2013-01-01

    The objective of this study was to get a comprehensive understanding of how genes in chicken shell gland modulate eggshell strength at the early stage of active calcification. Four 32-week old of purebred Xianju hens with consistent high or low shell breakage strength were grouped into two pairs. Using Affymetrix Chicken Array, a whole-transcriptome analysis was performed on hen’s shell gland at 9 h post oviposition. Gene ontology enrichment analysis for differentially expressed (DE) transcripts was performed using the web-based GOEAST, and the validation of DE-transcripts was tested by qRT-PCR. 1,195 DE-transcripts, corresponding to 941 unique genes were identified in hens with strong eggshell compared to weak shell hens. According to gene ontology annotations, there are 77 DE-transcripts encoding ion transporters and secreted extracellular matrix proteins, and at least 26 DE-transcripts related to carbohydrate metabolism or post-translation glycosylation modification; furthermore, there are 88 signaling DE-transcripts. GO term enrichment analysis suggests that some DE-transcripts mediate reproductive hormones or neurotransmitters to affect eggshell quality through a complex suite of biophysical processes. These results reveal some candidate genes involved with eggshell strength at the early stage of active calcification which may facilitate our understanding of regulating mechanisms of eggshell quality. PMID:25049830

  12. Part of Ran Is Associated with AKAP450 at the Centrosome: Involvement in Microtubule-organizing Activity

    PubMed Central

    Keryer, Guy; Di Fiore, Barbara; Celati, Claude; Lechtreck, Karl Ferdinand; Mogensen, Mette; Delouvée, Annie; Lavia, Patrizia; Bornens, Michel; Tassin, Anne-Marie

    2003-01-01

    The small Ran GTPase, a key regulator of nucleocytoplasmic transport, is also involved in microtubule assembly and nuclear membrane formation. Herein, we show by immunofluorescence, immunoelectron microscopy, and biochemical analysis that a fraction of Ran is tightly associated with the centrosome throughout the cell cycle. Ran interaction with the centrosome is mediated by the centrosomal matrix A kinase anchoring protein (AKAP450). Accordingly, when AKAP450 is delocalized from the centrosome, Ran is also delocalized, and as a consequence, microtubule regrowth or anchoring is altered, despite the persisting association of ?-tubulin with the centrosome. Moreover, Ran is recruited to Xenopus sperm centrosome during its activation for microtubule nucleation. We also demonstrate that centrosomal proteins such as centrin and pericentrin, but not ?-tubulin, AKAP450, or ninein, undertake a nucleocytoplasmic exchange as they concentrate in the nucleus upon export inhibition by leptomycin B. Together, these results suggest a challenging possibility, namely, that centrosome activity could depend upon nucleocytoplasmic exchange of centrosomal proteins and local Ran-dependent concentration at the centrosome. PMID:14517334

  13. NADPH-diaphorase activity in the nociceptive pathways of land snail Megalobulimus abbreviatus: the involvement of pedal ganglia.

    PubMed

    Rigon, Paula; de Castilhos, Juliana; Saur, Lisiani; Rodrigues, Mariana F; Achaval, Matilde; Xavier, Léder L

    2009-12-01

    NADPH-diaphorase (NADPH-d) is a histochemical marker for nitric oxide synthase (NOS), widely used to identify nitric oxide (NO) producing cells in the nervous system of both vertebrates and invertebrates. Using NADPH-d histochemistry and semi-quantitative optical densitometry, we characterized the NO-producing neurons in the pedal ganglia of young and adult Megalobulimus abbreviatus, subjected to aversive thermal stimulus. The animals were killed at different times (3, 6, 12 and 24 h) following stimulus. The enzymatic activity was detected in different cellular subsets and neuronal processes. In all the studied pedal ganglia subregions, the optical density of positive neurons (P < 0.05) and neuropilar area 1 (P < 0.01) was significantly different in treated animals when compared to controls. The increase in nitrergic activity induced by nociceptive stimulus suggests the involvement of NO in the nociceptive circuit of M. abbreviatus, which is well maintained throughout evolution, and could be helpful in drawing cellular homologies with other gastropods. PMID:20012757

  14. AMPA-receptor activation is involved in the antiamnesic effect of DM 232 (unifiram) and DM 235 (sunifiram).

    PubMed

    Galeotti, N; Ghelardini, C; Pittaluga, A; Pugliese, A M; Bartolini, A; Manetti, D; Romanelli, M N; Gualtieri, F

    2003-12-01

    DM 232 and DM 235 are novel antiamnesic compounds structurally related to ampakines. The involvement of AMPA receptors in the mechanism of action of DM 232 and DM 235 was, therefore, investigated in vivo and in vitro. Both compounds (0.1 mg/kg(-1) i.p.) were able to reverse the amnesia induced by the AMPA receptor antagonist NBQX (30 mg/kg(-1) i.p.) in the mouse passive avoidance test. At the effective doses, the investigated compounds did not impair motor coordination, as revealed by the rota rod test, nor modify spontaneous motility and inspection activity, as revealed by the hole board test. DM 232 and DM 235 reversed the antagonism induced by kynurenic acid of the NMDA-mediated release of [(3)H]NA in the kynurenate test performed in rat hippocampal slices. This effect was abolished by NBQX. DM 232 increases, in a concentration dependent manner, excitatory synaptic transmission in the rat hippocampus in vitro. These results suggest that DM 232 and DM 235 act as cognition enhancers through the activation of the AMPA-mediated neurotransmission system. PMID:14600801

  15. Autophagy Activation Is Involved in 3,4-Methylenedioxymethamphetamine (‘Ecstasy’)—Induced Neurotoxicity in Cultured Cortical Neurons

    PubMed Central

    Li, I-Hsun; Ma, Kuo-Hsing; Weng, Shao-Ju; Huang, Shiang-Suo; Liang, Chang-Min; Huang, Yuahn-Sieh

    2014-01-01

    Autophagic (type II) cell death, characterized by the massive accumulation of autophagic vacuoles in the cytoplasm of cells, has been suggested to play pathogenetic roles in cerebral ischemia, brain trauma, and neurodegenerative disorders. 3,4-Methylenedioxymethamphetamine (MDMA or ecstasy) is an illicit drug causing long-term neurotoxicity in the brain. Apoptotic (type I) and necrotic (type III) cell death have been implicated in MDMA-induced neurotoxicity, while the role of autophagy in MDMA-elicited neurotoxicity has not been investigated. The present study aimed to evaluate the occurrence and contribution of autophagy to neurotoxicity in cultured rat cortical neurons challenged with MDMA. Autophagy activation was monitored by expression of microtubule-associated protein 1 light chain 3 (LC3; an autophagic marker) using immunofluorescence and western blot analysis. Here, we demonstrate that MDMA exposure induced monodansylcadaverine (MDC)- and LC3B-densely stained autophagosome formation and increased conversion of LC3B-I to LC3B-II, coinciding with the neurodegenerative phase of MDMA challenge. Autophagy inhibitor 3-methyladenine (3-MA) pretreatment significantly attenuated MDMA-induced autophagosome accumulation, LC3B-II expression, and ameliorated MDMA-triggered neurite damage and neuronal death. In contrast, enhanced autophagy flux by rapamycin or impaired autophagosome clearance by bafilomycin A1 led to more autophagosome accumulation in neurons and aggravated neurite degeneration, indicating that excessive autophagosome accumulation contributes to MDMA-induced neurotoxicity. Furthermore, MDMA induced phosphorylation of AMP-activated protein kinase (AMPK) and its downstream unc-51-like kinase 1 (ULK1), suggesting the AMPK/ULK1 signaling pathway might be involved in MDMA-induced autophagy activation. PMID:25551657

  16. ERK1/2 pathway is involved in renal gluconeogenesis inhibition under conditions of lowered NADPH oxidase activity.

    PubMed

    Winiarska, Katarzyna; Jarzyna, Robert; Dzik, Jolanta M; Jagielski, Adam K; Grabowski, Michal; Nowosielska, Agata; Focht, Dorota; Sierakowski, Bartosz

    2015-04-01

    The aim of this study was to elucidate the mechanisms involved in the inhibition of renal gluconeogenesis occurring under conditions of lowered activity of NADPH oxidase (Nox), the enzyme considered to be one of the main sources of reactive oxygen species in kidneys. The in vitro experiments were performed on primary cultures of rat renal proximal tubules, with the use of apocynin, a selective Nox inhibitor, and TEMPOL (4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl), a potent superoxide radical scavenger. In the in vivo experiments, Zucker diabetic fatty (ZDF) rats, a well established model of diabetes type 2, were treated with apocynin solution in drinking water. The main in vitro findings are the following: (1) both apocynin and TEMPOL attenuate the rate of gluconeogenesis, inhibiting the step catalyzed by phosphoenolpyruvate carboxykinase (PEPCK), a key enzyme of the process; (2) in the presence of the above-noted compounds the expression of PEPCK and the phosphorylation of transcription factor CREB and ERK1/2 kinases are lowered; (3) both U0126 (MEK inhibitor) and 3-(2-aminoethyl)-5-((4-ethoxyphenyl)methylene)-2,4-thiazolidinedione (ERK inhibitor) diminish the rate of glucose synthesis via mechanisms similar to those of apocynin and TEMPOL. The observed apocynin in vivo effects include: (1) slight attenuation of hyperglycemia; (2) inhibition of renal gluconeogenesis; (3) a decrease in renal PEPCK activity and content. In view of the results summarized above, it can be concluded that: (1) the lowered activity of the ERK1/2 pathway is of importance for the inhibition of renal gluconeogenesis found under conditions of lowered superoxide radical production by Nox; (2) the mechanism of this phenomenon includes decreased PEPCK expression, resulting from diminished activity of transcription factor CREB; (3) apocynin-evoked inhibition of renal gluconeogenesis contributes to the hypoglycemic action of this compound observed in diabetic animals. Thus, the study has delivered some new insights into the recently discussed issue of the usefulness of Nox inhibition as a potential antidiabetic strategy. PMID:25601753

  17. Involvement of ?7 nAChR subtype in rat oxaliplatin-induced neuropathy: effects of selective activation.

    PubMed

    Di Cesare Mannelli, Lorenzo; Pacini, Alessandra; Matera, Carlo; Zanardelli, Matteo; Mello, Tommaso; De Amici, Marco; Dallanoce, Clelia; Ghelardini, Carla

    2014-04-01

    Oxaliplatin, unlike other platinum anticancer agents, has only mild toxic effects on the hematopoietic, urinary and gastrointestinal systems. Its dose-limiting side effect is neurotoxicity that may evolve to a neuropathic syndrome which is difficult to treat. In this study we treated rats with oxaliplatin (2.4 mg/kg/day intraperitoneally, for 3 weeks), and observed that expression levels of the ?7 nicotinic acetylcholine receptor (nAChR) subunit were dramatically decreased both in the peripheral and central nervous system. The repeated administration (30 mg/kg/day per os, for 3 weeks) of (R)-ICH3, the most active enantiomer of a novel ?7 nAChR agonist, and of PNU-282987 prevented the receptor down-regulation. On the other hand, both agonists per se up-regulated the ?7 nAChR subunit compared to control. (R)-ICH3 and PNU-282987 significantly reduced oxaliplatin-dependent alterations of the pain threshold when noxious or non-noxious stimuli were used. Further ex vivo analysis highlighted their neuroprotective effects in dorsal root ganglia and peripheral nerves. The two agonists did not prevent the increase in microglia cell number induced by oxaliplatin in the central nervous system. Astrocyte density was enhanced by the agonist treatment in the spinal cord, thalamus and somatosensory area 1 as opposed to the effects of oxaliplatin treatment. (R)-ICH3 and PNU-282987 per se increased glial cell number in a region-specific manner. In summary, ?7 nAChR is involved in oxaliplatin-dependent neuropathology and the agonists (R)-ICH3 and PNU-282987 reduce pain and protect nervous tissue with concomitant glial activation. Since glial cells play a role both in pain and in neuroprotection, an ?7 AChR-dependent modulation of glial functions is suggested to distinguish rescue signals from the pathological pain-mediating pathway. PMID:24225197

  18. Fibroblast growth factors 7 and 10 are involved in ameloblastoma proliferation via the mitogen-activated protein kinase pathway.

    PubMed

    Nakao, Yu; Mitsuyasu, Takeshi; Kawano, Shintaro; Nakamura, Norifumi; Kanda, Shiori; Nakamura, Seiji

    2013-11-01

    Ameloblastoma is an epithelial benign tumor of the odontogenic apparatus and its growth mechanisms are not well understood. Fibroblast growth factor (FGF) 3, FGF7 and FGF10, which are expressed by the neural crest-derived ectomesenchymal cells, induce the proliferation of odontogenic epithelial cells during tooth development. Therefore, we examined the expression and function of these FGFs in ameloblastoma. We examined 32 cases of ameloblastoma as well as AM-1 cells (an ameloblastoma cell line) and studied the expression of FGF3, FGF7, FGF10 and their specific receptors, namely, FGF receptor (FGFR) 1 and FGFR2. Proliferation, mitogen-activated protein kinase (MAPK) signaling and PI3K signaling were examined in AM-1 cells after the addition of FGF7, FGF10 and these neutralizing antibodies. The expression of FGF7, FGF10, FGFR1 and FGFR2 was detected in ameloblastoma cells and AM-1 cells, while that of FGF3 was not. FGF7 and FGF10 stimulated AM-1 cell proliferation and phosphorylation of p44/42 MAPK. However, Akt was not phosphorylated. Blocking the p44/42 MAPK pathway by using a specific mitogen-activated protein/extracellular signal-regulated kinase (MEK) inhibitor (U0126) completely neutralized the effects of FGF7 and FGF10 on AM-1 cell proliferation. However, Anti FGF7 and FGF10 neutralizing antibodies did not decrease cell proliferation and MAPK phosphorylation of AM-1 cells. These results suggested that FGF7 and FGF10 are involved in the proliferation of ameloblastoma cells through the MAPK pathway. PMID:24002438

  19. Fibroblast growth factors 7 and 10 are involved in ameloblastoma proliferation via the mitogen-activated protein kinase pathway

    PubMed Central

    NAKAO, YU; MITSUYASU, TAKESHI; KAWANO, SHINTARO; NAKAMURA, NORIFUMI; KANDA, SHIORI; NAKAMURA, SEIJI

    2013-01-01

    Ameloblastoma is an epithelial benign tumor of the odontogenic apparatus and its growth mechanisms are not well understood. Fibroblast growth factor (FGF) 3, FGF7 and FGF10, which are expressed by the neural crest-derived ectomesenchymal cells, induce the proliferation of odontogenic epithelial cells during tooth development. Therefore, we examined the expression and function of these FGFs in ameloblastoma. We examined 32 cases of ameloblastoma as well as AM-1 cells (an ameloblastoma cell line) and studied the expression of FGF3, FGF7, FGF10 and their specific receptors, namely, FGF receptor (FGFR) 1 and FGFR2. Proliferation, mitogen-activated protein kinase (MAPK) signaling and PI3K signaling were examined in AM-1 cells after the addition of FGF7, FGF10 and these neutralizing antibodies. The expression of FGF7, FGF10, FGFR1 and FGFR2 was detected in ameloblastoma cells and AM-1 cells, while that of FGF3 was not. FGF7 and FGF10 stimulated AM-1 cell proliferation and phosphorylation of p44/42 MAPK. However, Akt was not phosphorylated. Blocking the p44/42 MAPK pathway by using a specific mitogen-activated protein/extracellular signal-regulated kinase (MEK) inhibitor (U0126) completely neutralized the effects of FGF7 and FGF10 on AM-1 cell proliferation. However, Anti FGF7 and FGF10 neutralizing antibodies did not decrease cell proliferation and MAPK phosphorylation of AM-1 cells. These results suggested that FGF7 and FGF10 are involved in the proliferation of ameloblastoma cells through the MAPK pathway. PMID:24002438

  20. Luteinizing hormone stimulation of in vitro ovulation in brook trout (Salvelinus fontinalis) involves follicle contraction and activation of proteolytic genes.

    PubMed

    Crespo, Diego; Pramanick, Kousik; Goetz, Frederick W; Planas, Josep V

    2013-07-01

    Luteinizing hormone (LH) is an essential hormone for the stimulation of the ovulatory process in vertebrates. However, little is known in fish regarding the different mechanisms induced by LH during ovulation that facilitate the rupture of the follicle wall and the subsequent expulsion of the mature oocyte. In this study, the effects of salmon LH (sLH) on in vitro ovulation were investigated in brook trout (Salvelinus fontinalis) isolated follicles. sLH significantly stimulated in vitro ovulation and contraction of brook trout preovulatory follicles. In order to investigate the possible involvement of proteolytic events in the ovulatory action of LH, the expression of genes known to have a crucial role in the degradation of follicle wall structure was examined. Our results show that sLH clearly stimulated the mRNA expression levels of matrix metalloproteinases (MMPs; including mmp2 and mmp19) and other enzymes with proteolytic action during ovulation, such as a disintegrin and metalloproteinase with thrombospondin-like motifs 1 (adamts1) and plasminogen (plg), in brook trout preovulatory follicles. In addition, the expression of mmp2, adamts1 and plg increased in brook trout follicles during the progression of LH-induced ovulation. Interestingly, the expression of tissue inhibitor of matrix metalloproteinase 2 (timp2), a known regulator of MMP2 activity, paralleled that of mmp2, suggesting the existence of a controlled mechanism of MMP2 action. Therefore, the known increase in proteolytic activity during ovulation in fish could be the result of the stimulation of the expression of proteolytic enzymes by LH in preovulatory follicles. We propose that LH may stimulate ovulation in brook trout follicles by stimulating proteolysis of the follicle wall and by stimulating follicle contraction. PMID:23500674

  1. CD48 is a counter-receptor for mouse CD2 and is involved in T cell activation

    PubMed Central

    1992-01-01

    CD2 is an intercellular adhesion molecule that has been implicated in T cell activation and differentiation both in humans and mice. Although the ligand for human CD2 has been defined as LFA-3, that for murine CD2 has not been identified yet. To identify the ligand for mouse CD2, we generated a chimeric molecule consisting of the extracellular domain of mouse CD2 and human immunoglobulin (Ig)G1 Fc (mCD2Rg). A hamster monoclonal antibody (mAb), HM48-1, was established by screening mAbs that could block the binding of mCD2Rg to T cell lines at the ligand site. The putative mouse CD2 ligand recognized by this mAb was a glycosyl phosphatidylinositol-anchored glycoprotein with an apparent molecular mass of 45 kD, which were shared characteristics with human LFA-3. However, its expression was predominantly restricted to hematopoietic cells, unlike human LFA-3. Protein microsequencing analysis for the NH2-terminal 18 amino acid residues of the affinity- purified HM48-1 antigen revealed that it is almost identical with mouse CD48. This identity was further confirmed by the reactivity of HM48-1 with a soluble recombinant CD48 (sCD48) protein and the molecule recognized by a rat mAb raised against sCD48. A rat anti-CD48 mAb blocked the mCD2Rg binding as well as HM48-1. Moreover, sCD48 also inhibited the mCD2Rg binding to the cellular ligand. Finally, like anti- CD2 mAb, HM48-1 inhibited the phytohemagglutinin response and, when crosslinked, augmented the anti-CD3 response of splenic T cells. These results indicate that CD48 is a ligand for mouse CD2 and is involved in regulating T cell activation. PMID:1383383

  2. SENSITIVE TO PROTON RHIZOTOXICITY1, CALMODULIN BINDING TRANSCRIPTION ACTIVATOR2, and Other Transcription Factors Are Involved in ALUMINUM-ACTIVATED MALATE TRANSPORTER1 Expression1[OPEN

    PubMed Central

    Tokizawa, Mutsutomo; Kobayashi, Yuriko; Saito, Tatsunori; Kobayashi, Masatomo; Iuchi, Satoshi; Nomoto, Mika; Tada, Yasuomi; Yamamoto, Yoshiharu Y.; Koyama, Hiroyuki

    2015-01-01

    In Arabidopsis (Arabidopsis thaliana) the root apex is protected from aluminum (Al) rhizotoxicity by excretion of malate, an Al chelator, by ALUMINUM-ACTIVATED MALATE TRANSPORTER1 (AtALMT1). AtALMT1 expression is fundamentally regulated by the SENSITIVE TO PROTON RHIZOTOXICITY1 (STOP1) zinc finger protein, but other transcription factors have roles that enable Al-inducible expression with a broad dynamic range. In this study, we characterized multiple cis-elements in the AtALMT1 promoter that interact with transcription factors. In planta complementation assays of AtALMT1 driven by 5? truncated promoters of different lengths showed that the promoter region between –540 and 0 (the first ATG) restored the Al-sensitive phenotype of atalm1 and thus contains cis-elements essential for AtALMT1 expression for Al tolerance. Computation of overrepresented octamers showed that eight regions in this promoter region contained potential cis-elements involved in Al induction and STOP1 regulation. Mutation in a position around –297 from the first ATG completely inactivated AtALMT1 expression and Al response. In vitro binding assays showed that this region contained the STOP1 binding site, which accounted for the recognition by four zinc finger domains of the protein. Other positions were characterized as cis-elements that regulated expression by repressors and activators and a transcription factor that determines root tip expression of AtALMT1. From the consensus of known cis-elements, we identified CALMODULIN-BINDING TRANSCRIPTION ACTIVATOR2 to be an activator of AtALMT1 expression. Al-inducible expression of AtALMT1 changed transcription starting sites, which increased the abundance of transcripts with a shortened 5? untranslated region. The present analyses identified multiple mechanisms that regulate AtALMT1 expression. PMID:25627216

  3. SENSITIVE TO PROTON RHIZOTOXICITY1, CALMODULIN BINDING TRANSCRIPTION ACTIVATOR2, and Other Transcription Factors Are Involved in ALUMINUM-ACTIVATED MALATE TRANSPORTER1 Expression.

    PubMed

    Tokizawa, Mutsutomo; Kobayashi, Yuriko; Saito, Tatsunori; Kobayashi, Masatomo; Iuchi, Satoshi; Nomoto, Mika; Tada, Yasuomi; Yamamoto, Yoshiharu Y; Koyama, Hiroyuki

    2015-03-01

    In Arabidopsis (Arabidopsis thaliana) the root apex is protected from aluminum (Al) rhizotoxicity by excretion of malate, an Al chelator, by ALUMINUM-ACTIVATED MALATE TRANSPORTER1 (AtALMT1). AtALMT1 expression is fundamentally regulated by the SENSITIVE TO PROTON RHIZOTOXICITY1 (STOP1) zinc finger protein, but other transcription factors have roles that enable Al-inducible expression with a broad dynamic range. In this study, we characterized multiple cis-elements in the AtALMT1 promoter that interact with transcription factors. In planta complementation assays of AtALMT1 driven by 5' truncated promoters of different lengths showed that the promoter region between -540 and 0 (the first ATG) restored the Al-sensitive phenotype of atalm1 and thus contains cis-elements essential for AtALMT1 expression for Al tolerance. Computation of overrepresented octamers showed that eight regions in this promoter region contained potential cis-elements involved in Al induction and STOP1 regulation. Mutation in a position around -297 from the first ATG completely inactivated AtALMT1 expression and Al response. In vitro binding assays showed that this region contained the STOP1 binding site, which accounted for the recognition by four zinc finger domains of the protein. Other positions were characterized as cis-elements that regulated expression by repressors and activators and a transcription factor that determines root tip expression of AtALMT1. From the consensus of known cis-elements, we identified CALMODULIN-BINDING TRANSCRIPTION ACTIVATOR2 to be an activator of AtALMT1 expression. Al-inducible expression of AtALMT1 changed transcription starting sites, which increased the abundance of transcripts with a shortened 5' untranslated region. The present analyses identified multiple mechanisms that regulate AtALMT1 expression. PMID:25627216

  4. Very late activation antigen 4-vascular cell adhesion molecule 1 interaction is involved in the formation of erythroblastic islands

    PubMed Central

    1995-01-01

    Erythroblastic islands are anatomical units consisting of a central macrophage surrounded by erythroblasts. We studied the adhesion molecules involved in the formation of these structures. Central macrophages of erythroblastic islands isolated from the spleens of phlebotomized mice were clearly stained for vascular cell adhesion molecule 1 (VCAM-1). The surrounding erythroblasts of the erythroblastic islands strongly expressed the alpha 4 integrin of very late activation antigen 4 (VLA-4: alpha 4 beta 1 integrin), the counter receptor of VCAM-1, whereas most reticulocytes and erythrocytes did not. Both monoclonal antibodies (mAbs) against alpha 4 integrin and VCAM-1 disrupted the erythroblastic islands cultured in the presence of erythropoietin. Moreover, adhesion of splenic erythroblasts to tumor necrosis factor alpha-stimulated mouse splenic endothelial cells, which showed high expression of VCAM-1 but not intercellular adhesion molecule 1, was inhibited by the anti-VCAM-1 and anti-alpha 4 mAbs. These findings suggest that VLA-4-VCAM-1 interaction plays a crucial role in the formation of erythroblastic islands. PMID:7528776

  5. Paramagnetic 3d coordination complexes involving redox-active tetrathiafulvalene derivatives: an efficient approach to elaborate multi-properties materials.

    PubMed

    Pointillart, Fabrice; Golhen, Stéphane; Cador, Olivier; Ouahab, Lahcène

    2013-02-14

    The elaboration of multifunctional materials is a great challenge for the physical chemistry community and the studies of molecular materials exhibiting coexistence or synergy between two or more properties are very active. In particular, molecular compounds displaying electrical conductivity and magnetic interactions are currently the subject of intensive studies. Two approaches are now well-known and are explored. On the one hand, the interactions between mobile electrons of the organic network (? electrons) and localized electrons of paramagnetic transition metal (d electrons) take place through space. On the other hand, these interactions take place through covalent chemical bonds. In the latter, the probability to have significant interaction between ? and d electrons is enhanced compared to the first approach. In this perspective article, we will give an overview of the known coordination complexes involving tetrathiafulvalene derivatives as ligands for paramagnetic 3d ions and we will describe their physical properties. If necessary, the coexistence or synergy between electrical conductivity, magnetism and other properties will be highlighted. PMID:23208602

  6. BRI1 activity in the root meristem involves post-transcriptional regulation of PIN auxin efflux carriers.

    PubMed

    Hacham, Yael; Sela, Ayala; Friedlander, Lilach; Savaldi-Goldstein, Sigal

    2012-01-01

    Spatiotemporal coordination between multiple hormonal pathways is a key determinant of plant growth. This coordination can be mediated by distribution of the auxin network via the action of PIN auxin efflux carriers. We showed that brassinosteroids (BRs) promote cell proliferation and cell expansion of meristematic cells. Hence, roots with high epidermal expression of the BR receptor BRI1 have enlarged meristem whereas bri1 mutant has a reduced meristem size. Because the extent of mitotic activity and differentiation is tightly linked to auxin gradient we further asked how the BR pathway integrates with current proposed models for PIN regulation.  We showed that the small meristem of BR deficient plants does not involve transcriptional modulation of PIN 1, 3 and 7 genes.  Here, we found that PIN2 and PIN4 are under transcriptional regulation.  However, their accumulation in the epidermis/cortex and columella respectively was also determined by BRs in a post-transcriptional manner.  Thus, BRs impinge on auxin distribution through distinct regulatory modes and the self-organizing auxin system represents at least one mechanism that contributes to BR-mediated growth. PMID:22231282

  7. Toluene biodegradation in a solid/liquid system involving immobilized activated sludge and silicone oil as pollutant reservoir.

    PubMed

    Diz Castro, Manuel; Gómez-Díaz, Diego; Amrane, Abdeltif; Couvert, Annabelle

    2015-02-01

    A solid/liquid system involving activated sludge immobilized in an agar medium and a non-aqueous phase liquid containing the target pollutant has been considered to treat a model hydrophobic volatile organic compound, toluene. The positive impact of the use of a multiphase bioreactor is that the organic phase constitutes a pollutant reservoir and also helps to overcome possible pollutant toxicity. In addition and to overcome the drawbacks of the use of a solid organic phase (high pressure drop and low mass transfer) instead of a liquid organic phase, the considered solid phase was the aqueous. Consequently, silicone oil (polydimethylsiloxane) which showed its relevance for implementation in multiphase bioreactors was used. Promising results were observed from the analysis of toluene in the gaseous phase; for an initial amount of 2?g?L(-1) related to the organic phase, a v/v ratio of 0.5 of the organic phase to the aqueous agar phase, total toluene consumption was observed in about 9 days, leading to a global biodegradation rate of approximately 3.1?mg?L(-1)?h(-1), namely in the range of values previously observed in liquid/liquid systems. PMID:25187471

  8. High-mobility group box-1 was released actively and involved in LPS induced depressive-like behavior.

    PubMed

    Wu, Teng-Yun; Liu, Lei; Zhang, Wei; Zhang, Yi; Liu, Yun-Zi; Shen, Xiao-Liang; Gong, Hong; Yang, Yuan-Yuan; Bi, Xiao-Ying; Jiang, Chun-Lei; Wang, Yun-Xia

    2015-05-01

    Depression disorder is a common mental illness, of which the pathogenesis is not well understood. Studies suggest that immunity imbalance and up-regulation of pro-inflammatory cytokines may be associated with the pathogenesis of depression. High-mobility group box 1 protein (HMGB1) has gained much attention as an important player in innate immune responses and an modulating factor in several inflammatory diseases. Here we sought to explore the role of HMGB1 in the development of depression. Depression model was established with low dose of lipopolysaccharide (LPS) administration. Depressive behavior was reflected with increased immobility time in tail suspension test. Accompanying with depressive-like behavior, translocation of HMGB1 from nuclei to cytoplasm was observed by immunofluorescence assays. Meanwhile, no significant necrosis was observed evaluated by hematoxylin-eosin staining. These data indicated that HMGB1 was released actively in the central nervous system. In addition, treating the mice with human recombinant HMGB1 (rHMGB1) could induce the development of depressive-like behavior. Blockage of HMGB1 with GZA abrogated the depressive-like behavior induced by LPS or rHMGB1. These results implicated that HMGB1 was involved in LPS-induced depressive-like behavior. PMID:25795092

  9. HIV-1 kills renal tubular epithelial cells in vitro by triggering an apoptotic pathway involving caspase activation and Fas upregulation.

    PubMed Central

    Conaldi, P G; Biancone, L; Bottelli, A; Wade-Evans, A; Racusen, L C; Boccellino, M; Orlandi, V; Serra, C; Camussi, G; Toniolo, A

    1998-01-01

    HIV-infected patients suffer several renal syndromes, which can progress rapidly from renal insufficiency to end-stage renal disease. Histologically, HIV-induced nephropathy is characterized by prominent tubulopathy with apoptosis of tubular cells. Clinical and experimental evidence suggests that renal injury may be directly related to virus infection. Although HIV-1 is a polytropic and not solely lymphotropic pathogen, the susceptibility of renal cells to HIV-1 remains to be determined. This paper demonstrates in vitro the permissiveness of proximal tubular epithelial cells (PTEC) to HIV-1 and describes the effects of PTEC infection to explain the pathogenesis of tubular damage in vivo. The results indicate that PTEC express HIV-specific receptor and coreceptors and sustain virus replication. We observed that HIV-1 infection causes the death of tubular cells by triggering an apoptotic pathway involving caspase activation. Fas upregulation but not Fas ligand expression was found in the infected PTEC. However, after HIV-1 infection, tubular cells became susceptible to apoptosis induced through Fas stimulation. Caspase inhibition prevented the death of the infected PTEC in spite of persistent viral replication. These findings may explain the prominent histopathology of HIV-associated nephropathy and demonstrate that the apoptosis of nonlymphoid cells can be directly induced by HIV-1. PMID:9854039

  10. Involvement of a high-mobility-group protein in the transcriptional activity of herpes simplex virus latency-active promoter 2.

    PubMed Central

    French, S W; Schmidt, M C; Glorioso, J C

    1996-01-01

    Latency-active promoter 2 (LAP 2) is a TATA-less promoter in herpes simplex virus type 1 (HSV-1) that can express genes during viral latency. Four regions of LAP2 are protected from DNase I digestion in vitro by either HeLa cell nuclear extracts or purified Sp1. Transient gene expression assays of LAP2 substitution mutants demonstrate that two of the regions protected by Sp1 and three other regions protected by nuclear extract are important for promoter function. The mutation causing the most significant reduction in expression alters a stretch of 23 thymidine residues (T23) that binds a protein with several properties common to high-mobility-group (HMG) proteins. The T23 binding activity is heat stable, can be inhibited by poly(dA-dT).poly(dA-dT), and is inhibited by minor-groove-binding drugs. Antiserum directed against HMG I(Y) blocked the formation of one of the DNA-protein complexes on the T23 oligonucleotide, suggesting that a protein antigenically related to HMG I(Y) binds to LAP2 in vitro. Direct evidence of HMG I(Y) involvement in LAP2 function is provided by the findings that recombinant HMG I(Y) protein facilitates Sp1 binding to LAP2 in mobility shift assays and that antisense HMG I(Y) RNA specifically inhibits LAP2 function in vivo. These results suggest that DNA structure may be an important determinant of the activity of a promoter that is capable of escaping the global shutoff of transcription that occurs during viral latency. PMID:8816451

  11. Induction of Id-1 by FGF-2 involves activity of EGR-1 and sensitizes neuroblastoma cells to cell death.

    PubMed

    Passiatore, Giovanni; Gentilella, Antonio; Rom, Slava; Pacifici, Marco; Bergonzini, Valeria; Peruzzi, Francesca

    2011-07-01

    Inhibitor of differentiation-1 (Id-1) is a member of helix-loop-helix (HLH) family of proteins that regulate gene transcription through their inhibitory binding to basic-HLH transcription factors. Similarly to other members of this family, Id-1 is involved in the repression of cell differentiation and activation of cell growth. The dual function of Id-1, inhibition of differentiation, and stimulation of cell proliferation, might be interdependent, as cell differentiation is generally coupled with the exit from the cell cycle. Fibroblast growth factor-2 (FGF-2) has been reported to play multiple roles in different biological processes during development of the central nervous system (CNS). In addition, FGF-2 has been described to induce "neuronal-like" differentiation and trigger apoptosis in neuroblastoma SK-N-MC cells. Although regulation of Id-1 protein by several mitogenic factors is well-established, little is known about the role of FGF-2 in the regulation of Id-1. Using human neuroblastoma cell line, SK-N-MC, we found that treatment of these cells with FGF-2 resulted in early induction of both Id-1 mRNA and protein. The induction occurs within 1 h from FGF-2 treatment and is mediated by ERK1/2 pathway, which in turn stimulates expression of the early growth response-1 (Egr-1) transcription factor. We also demonstrate direct interaction of Egr-1 with Id-1 promoter in vitro and in cell culture. Finally, inhibition of Id-1 expression results in G(2) /M accumulation of FGF-2-treated cells and delayed cell death. PMID:21506108

  12. Tongxinluo Protects against Pressure Overload–Induced Heart Failure in Mice Involving VEGF/Akt/eNOS Pathway Activation

    PubMed Central

    Wang, Bo; Yang, Qing; Bai, Wen-wu; Xing, Yi-fan; Lu, Xiao-ting; Sun, Yuan-yuan; Zhao, Yu-xia

    2014-01-01

    Background It has been demonstrated that Tongxinluo (TXL), a traditional Chinese medicine compound, improves ischemic heart disease in animal models via vascular endothelial growth factor (VEGF) and endothelial nitric oxide synthase (eNOS). The present study aimed to investigate whether TXL protects against pressure overload–induced heart failure in mice and explore the possible mechanism of action. Methods and Results Transverse aortic constriction (TAC) surgery was performed in mice to induce heart failure. Cardiac function was evaluated by echocardiography. Myocardial pathology was detected using hematoxylin and eosin or Masson trichrome staining. We investigated cardiomyocyte ultrastructure using transmission electron microscopy. Angiogenesis and oxidative stress levels were determined using CD31 and 8-hydroxydeoxyguanosine immunostaining and malondialdehyde assay, respectively. Fetal gene expression was measured using real-time PCR. Protein expression of VEGF, phosphorylated (p)-VEGF receptor 2 (VEGFR2), p–phosphatidylinositol 3-kinase (PI3K), p-Akt, p-eNOS, heme oxygenase-1 (HO-1), and NADPH oxidase 4 (Nox4) were measured with western blotting. Twelve-week low- and high-dose TXL treatment following TAC improved cardiac systolic and diastolic function and ameliorated left ventricular hypertrophy, fibrosis, and myocardial ultrastructure derangement. Importantly, TXL increased myocardial capillary density significantly and attenuated oxidative stress injury in failing hearts. Moreover, TXL upregulated cardiac nitrite content and the protein expression of VEGF, p-VEGFR2, p-PI3K, p-Akt, p-eNOS, and HO-1, but decreased Nox4 expression in mouse heart following TAC. Conclusion Our findings indicate that TXL protects against pressure overload–induced heart failure in mice. Activation of the VEGF/Akt/eNOS signaling pathway might be involved in TXL improvement of the failing heart. PMID:24887083

  13. An activating transcription factor of Litopenaeus vannamei involved in WSSV genes Wsv059 and Wsv166 regulation.

    PubMed

    Li, Xiao-Yun; Yue, Hai-Tao; Zhang, Ze-Zhi; Bi, Hai-Tao; Chen, Yong-Gui; Weng, Shao-Ping; Chan, Siuming; He, Jian-Guo; Chen, Yi-Hong

    2014-12-01

    Members of activating transcription factor/cyclic adenosine 3', 5'-monophosphate response element binding protein (ATF/CREB) family are induced by various stress signals and function as effector molecules. Consequently, cellular changes occur in response to discrete sets of instructions. In this work, we found an ATF transcription factor in Litopenaeus vannamei designated as LvATF?. The full-length cDNA of LvATF? was 1388 bp long with an open reading frame of 939 bp that encoded a putative 313 amino acid protein. The protein contained a basic region-leucine zipper (bZip) domain that was a common feature among ATF/CREB transcription factors. LvATF? was highly expressed in intestines, gills, and heart. LvATF? expression was dramatically upregulated by white spot syndrome virus (WSSV) infection. Pull-down assay revealed that LvATF? had strong affinity to promoters of WSSV genes, namely, wsv059 and wsv166. Dual-luciferase reporter assay showed that LvATF? could upregulate the expression of wsv059 and wsv166. Knocked down LvATF? resulted in decreased expression of wsv059 and wsv166 in WSSV-challenged L. vannamei. Knocked down expression of wsv059 and wsv166 by RNA interference inhibited the replication and reduce the mortality of L. vannamei during WSSV challenge inoculation. The copy numbers of WSSV in wsv059 and wsv166 knocked down group were significant lower than in the control. These results suggested that LvATF? may be involved in WSSV replication by regulating the expression of wsv059 and wsv166. PMID:25172110

  14. Parent Involvement Activities in School Improvement Plans in the Northwest Region. Issues & Answers. REL 2008-No. 064

    ERIC Educational Resources Information Center

    Speth, Timothy; Saifer, Steffen; Forehand, Gregory

    2008-01-01

    Although the No Child Left Behind Act of 2001 (NCLB) spells out parent involvement requirements for schools in need of improvement, the majority of the Northwest Region school improvement plans reviewed failed to include such provisions. Reported findings include: (1) Despite a wide range of parent involvement practices discussed in legislation…

  15. Involvement of Human Resources in School Activities 1968-69. Research and Development Report; Volume III, Number Two.

    ERIC Educational Resources Information Center

    Ireland, Vera M.

    All principals in the elementary, middle, junior high and high schools of the Atlanta Public School System were requested to select one school project involving human resources which they considered to be significant and successful. The information solicited about each project included grade level, number of resource persons involved by category,…

  16. The use of parent involved take-home science activities during student teaching: Understanding the challenges of implementation

    NASA Astrophysics Data System (ADS)

    Zarazinski, Jill

    The purpose of this study was to identify student teachers use and implementation of Science in a Bag when it was no longer a required course-based assessment. This take-home science activity acted as the elaboration component of the 5Es lesson teacher candidates designed and taught in the classroom, utilized household items, and directly involved parents in their child's education. The purposeful sample was comprised of six teacher candidates during their student teaching practicum, the last semester of the childhood education teacher certification program. This collective case study centered on student teachers' use of the focused activity, Science in a Bag, in order to gain knowledge of challenges faced in applying take-home science kits and working with parents. Data collection was comprised of student teacher and parent interviews, candidate reflections, as well as in-class observations and discussions carried out during weekly seminars. Data collection occurred throughout the seven-week student teaching practicum. The four research questions were: 1) What factors do teacher candidates identify as interfering with their ability to implement Science in a Bag during student teaching placements? 2) What factors do teacher candidates identify as enhancing their ability to carry out Science in a Bag? 3) What forms of support do teacher candidates believe are important to their success in implementing Science in a Bag during student teaching? 4) How do teacher candidates deal with obstacles when implementing Science in a Bag? Despite the fact that no student teacher was prohibited from implementing Science in a Bag, the level to which candidates valued and utilized this instructional strategy varied compared to how they were taught and practiced it during the science methods course. Some student teachers attempted to hide their feelings toward Science in a Bag, however their actions revealed that they were simply carrying out the instructional strategy because they had agreed to implement it, not because they appreciated its worth to students and their families. Altering candidate beliefs in one semester prior to student teaching proved difficult, especially when cooperating teachers were demonstrating and encouraging methodologies which were frowned upon during the science methods coursework. Therefore, this study also raised issues with teacher education and identified the need to better align educational philosophies taught throughout the program and those showcased by cooperating teachers if science education reform is to transpire. Teacher candidates very often abandoned the inquiry-based modes of instruction taught to them during the science methods course prior to student teaching and replaced them with ideas and suggestions from their cooperating teacher, approaches which were more traditional and teacher-centered. Cooperating teacher opinions and suggestions appeared to take precedence over what was taught and practiced during their preparation coursework. Candidates' prior beliefs and experiences with education appeared to dominate their teaching repertoire. The culmination of their own K-12 education and much of their undergraduate courses made altering their beliefs toward inquiry-based methodologies difficult during only one semester prior to student teaching. Therefore, all candidates reverted back to some level of teacher-centered, recipe-like science lessons and tasks. It was also noted that the candidates' understanding of hands-on versus inquiry learning was often blurred. Hands-on learning was often demonstrated and applauded by cooperating teachers, as well as parents, once they responded to Science in a Bag surveys and interviews, further supporting this misconception by praising hands-on learning and in some cases stating it was the way students learned best. Most parents were willing to and enjoyed performing these take-home family activities. Some of the most frequent parent comments related to family time, being informed about the content their child was learning in school and the child taking on

  17. Production of active recombinant eIF5A: reconstitution in E.coli of eukaryotic hypusine modification of eIF5A by its coexpression with modifying enzymes.

    PubMed

    Park, Jong Hwan; Dias, Camila A O; Lee, Seung Bum; Valentini, Sandro R; Sokabe, Masaaki; Fraser, Christopher S; Park, Myung Hee

    2011-03-01

    Eukaryotic translation initiation factor 5A (eIF5A) is the only cellular protein that contains the polyamine-modified lysine, hypusine [N(?)-(4-amino-2-hydroxybutyl)lysine]. Hypusine occurs only in eukaryotes and certain archaea, but not in eubacteria. It is formed post-translationally by two consecutive enzymatic reactions catalyzed by deoxyhypusine synthase (DHS) and deoxyhypusine hydroxylase (DOHH). Hypusine modification is essential for the activity of eIF5A and for eukaryotic cell proliferation. eIF5A binds to the ribosome and stimulates translation in a hypusine-dependent manner, but its mode of action in translation is not well understood. Since quantities of highly pure hypusine-modified eIF5A is desired for structural studies as well as for determination of its binding sites on the ribosome, we have used a polycistronic vector, pST39, to express eIF5A alone, or to co-express human eIF5A-1 with DHS or with both DHS and DOHH in Escherichia coli cells, to engineer recombinant proteins, unmodified eIF5A, deoxyhypusine- or hypusine-modified eIF5A. We have accomplished production of three different forms of recombinant eIF5A in high quantity and purity. The recombinant hypusine-modified eIF5A was as active in methionyl-puromycin synthesis as the native, eIF5A (hypusine form) purified from mammalian tissue. The recombinant eIF5A proteins will be useful tools in future structure/function and the mechanism studies in translation. PMID:21131325

  18. Involvement of protein kinase C signalling and mitogen-activated protein kinase in the amebocyte-producing organ of Biomphalaria glabrata (Mollusca).

    PubMed

    Salamat, Zahra; Sullivan, John T

    2009-06-01

    Mechanisms that regulate hemocyte production in molluscs, at either the organismal or cellular levels, are not well understood. In the present study, 24-h saline cultures of the amebocyte-producing organ (APO) of the schistosome-transmitting snail Biomphalaria glabrata were used to test for the potential involvement of protein kinase C (PKC) signalling in hematopoiesis. Exposure to phorbol myristate acetate (PMA), an activator of PKC, resulted in an increase in the number of dividing hematopoietic cells in APOs from schistosome-resistant Salvador snails. PMA-induced cell division was blocked by treatment with U0126, an inhibitor of the mitogen-activated protein kinase kinase, MEK1/2. These results suggest that PKC-induced activation of the mitogen-activated protein kinase, ERK1/2, is involved in cell division in the APO. PMID:19183562

  19. Active and Avoidant Coping and Coping Efficacy as Mediators of the Relation of Maternal Involvement to Depressive Symptoms among Urban Adolescents

    Microsoft Academic Search

    Catherine E. Mosher; Hazel M. Prelow

    2007-01-01

    Our study tested an extension of the social resource model in an urban sample of 129 African American and 114 European American\\u000a adolescents. Maternal involvement was positively related to the use of active and avoidant coping strategies among youth of\\u000a both ethnicities. Additionally, use of active coping strategies was related to greater coping efficacy, which, in turn, was\\u000a associated with

  20. The antinociceptive activity of Muntingia calabura aqueous extract and the involvement of L-arginine/nitric oxide/cyclic guanosine monophosphate pathway in its observed activity in mice.

    PubMed

    Zakaria, Zainul Amiruddin; Sulaiman, Mohd Roslan; Jais, Abdul Manan Mat; Somchit, Muhammad Nazrul; Jayaraman, Kogilla Vani; Balakhrisnan, Ganesh; Abdullah, Fatimah Corazon

    2006-08-01

    The present study was carried out to investigate on the possible involvement of L-arginine/nitric oxide/cyclic guanosine monophosphate (L-arginine/NO/cGMP) pathway in the aqueous extract of Muntingia calabura (AEMC) leaves antinociception in mice assessed by abdominal constriction test. The AEMC, obtained by soaking the dried leaves in distilled water (DH(2)O) (1 : 2; w/v) for 24 h, was prepared in concentrations of 10%, 50% and 100% that were approximately equivalent to doses of 27, 135 and 270 mg/kg, and administered subcutaneously (s.c.) 5 min after pre-treatment (s.c.) of mice with DH(2)O, L-arginine (20 mg/kg), N(G)-monomethyl-L-arginine acetate (L-NMMA; 20 mg/kg), N(G)-nitro-L-arginine methyl esters (L-NAME; 20 mg/kg), methylene blue (MB) (20 mg/kg), respectively. The AEMC was found to exhibit a concentration-dependent antinociception after pre-challenge with DH(2)O. Interestingly, pre-treatment with L-arginine was found to block significantly (P < 0.05) the AEMC antinociception but only at the highest concentration (100%) of AEMC used. On the other hand, pre-treatment with L-NAME was found to significantly (P < 0.05) enhance the low concentration but inhibit the high concentration AEMC antinociception. MB was found to significantly (P < 0.05) enhance AEMC antinociception at all concentrations used. Except for the higher concentration of AEMC used, co-treatment with L-NAME was found to insignificantly and significantly (P < 0.05) reverse the L-arginine effect when given alone or with low concentration AEMC, respectively. In addition, co-treatment with MB significantly (P < 0.05) reversed the L-arginine effect when given alone or with 10% concentration AEMC but failed to affect the activity of the rest of concentrations used. As a conclusion, this study has demonstrated the involvement of L-arginine/NO/cGMP pathway in AEMC antinociception. PMID:16867020

  1. Activation of DNA Methyltransferase 1 by EBV LMP1 Involves c-Jun NH2Terminal Kinase Signaling

    Microsoft Academic Search

    Chia-Lung Tsai; Yen-Jung Lu; Chuen Hsueh; Ying Liang; Chi-Long Chen; Sai Wah Tsao; Ka-Po Tse; Yu-Sun Chang

    2006-01-01

    EBV latent membrane protein 1 (LMP1) activates cellular DNA methyltransferases, resultingin hypermethylation and silenc- ingof E-cadherin. However, the underlyingmechanism remains to be elucidated. In this study, we show that LMP1 directly induces the dnmt1 promoter activity through its COOH-terminal activation region-2 YYD domain. Using (i) LMP1 mutants, (ii) dominant negative mutants c-jun NH2- terminal kinase (JNK)-DN, p38-DN, and constitutive active

  2. eIF5A isoforms and cancer: two brothers for two functions?

    PubMed

    Caraglia, M; Park, M H; Wolff, E C; Marra, M; Abbruzzese, A

    2013-01-01

    Eukaryotic translation initiation factor 5A (eIF5A) is the only cellular protein that contains the unusual amino acid hypusine [N(?)-(4-amino-2-hydroxybutyl)lysine]. The role of hypusine formation in the eIF5A protein in the regulation of cell proliferation and apoptosis is addressed in the present review. Moreover, vertebrates carry two genes that encode two eIF5A isoforms, eIF5A-1 and eIF5A-2, which, in humans, are 84% identical. However, the biological functions of these two isoforms may be significantly different. In fact, eIF5A-1 is demonstrable in most cells of different histogenesis, whereas eIF5A-2 protein is detectable only in certain human cancer cells or tissues, suggesting its role as a potential oncogene. In this review we focus our attention on the involvement of eIF5A-1 in the triggering of an apoptotic program and in the regulation of cell proliferation. In addition, the potential oncogenic role and prognostic significance of eIF5A-2 in the prediction of the survival of cancer patients is described. eIF5A-1 and/or the eIF5A-2 isoform may serve as a new molecular diagnostic or prognostic marker or as a molecular target for anti-cancer therapy. PMID:22139412

  3. The Influence of Race and Ethnicity on Substance Use and Negative Activity Involvement among Monoracial and Multiracial Adolescents of the Southwest

    ERIC Educational Resources Information Center

    Jackson, Kelly F.; LeCroy, Craig W.

    2009-01-01

    This study examined predictors of substance use and negative activity involvement among a diverse sample of European American, African American, Hispanic, Native American, and multiracial early adolescents (n = 749) living in a large urban city in the Southwest United States. This study investigated a broad set of predictor variables that tap…

  4. Involvement & Participation. National Conference on Physical Activity for the Exceptional Individual (11th, San Diego, California, November 19-20, 1982).

    ERIC Educational Resources Information Center

    Greaves, Edward R.; Richmond, Alan

    This publication contains papers, presented at a conference about physical activities for the exceptional individual, concerning: (1) student interest/motivation; (2) swimming; (3) games; (4) wheelchairs; (5) movement education; (6) physical stress and bone growth; (7) parent involvement; (8) meningomyelocele; (9) blind athletes; (10) Project…

  5. ROLES PLAYED BY ESTERASE ACTIVITY AND BY A SODIUM CHANNEL MUTATION INVOLVED IN PYRETHROID RESISTANCE IN POPULATIONS OF BOOPHILUS MICROPLUS (ACARI:IXODIDAE) COLLECTED FROM YUCATAN, MEXICO

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pyrethroid resistance in Boophilus microplus (Canestrini) (Acari: Ixodidae) was studied by correlating discriminating-dose (DD) bioassay results and esterase activity or the frequency of a sodium channel mutation known to be involved in pyrethroid resistance in nine field strains of B. microplus fro...

  6. Involving Latino Parents.

    ERIC Educational Resources Information Center

    Quezada, Reyes L.; Diaz, Delia M.; Sanchez, Maria

    2003-01-01

    Describes barriers to Latino parent involvement in educational activities, factors to consider when involving Latino parents, and two examples of Latino involvement programs in California: Family Literacy Workshop at James Monroe Elementary School, Madera Unified School District, and Parents Take P.A.R.T. (Parent Assisted Reading Training) at…

  7. Mutational analysis of amino acid residues involved in catalytic activity of a family 18 chitinase from tulip bulbs.

    PubMed

    Suzukawa, Keisuke; Yamagami, Takeshi; Ohnuma, Takayuki; Hirakawa, Hideki; Kuhara, Satoru; Aso, Yoichi; Ishiguro, Masatsune

    2003-02-01

    We expressed chitinase-1 (TBC-1) from tulip bulbs (Tulipa bakeri) in E. coli cells and used site-directed mutagenesis to identify amino acid residues essential for catalytic activity. Mutations at Glu-125 and Trp-251 completely abolished enzyme activity, and activity decreased with mutations at Asp-123 and Trp-172 when glycolchitin was the substrate. Activity changed with the mutations of Trp-251 to one of several amino acids with side-chains of little hydrophobicity, suggesting that hydrophobic interaction of Trp-251 is important for the activity. Molecular dynamics (MD) simulation analysis with hevamine as the model compound showed that the distance between Asp-123 and Glu-125 was extended by mutation of Trp-251. Kinetic studies of Trp-251-mutated chitinases confirmed these various phenomena. The results suggested that Glu-125 and Trp-251 are essential for enzyme activity and that Trp-251 had a direct role in ligand binding. PMID:12728996

  8. Involvement of mitogen-activated protein kinases and NF{kappa}B in LPS-induced CD40 expression on human monocytic cells

    SciTech Connect

    Wu Weidong [Center for Environmental Medicine, Asthma, and Lung Biology, University of North Carolina, Chapel Hill, North Carolina 27599 (United States)]|[Department of Pediatrics, University of North Carolina, Chapel Hill, North Carolina 27599 (United States)], E-mail: Weidong_Wu@med.unc.edu; Alexis, Neil E. [Center for Environmental Medicine, Asthma, and Lung Biology, University of North Carolina, Chapel Hill, North Carolina 27599 (United States)]|[Department of Pediatrics, University of North Carolina, Chapel Hill, North Carolina 27599 (United States); Chen Xian [Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, North Carolina 27599 (United States)]|[Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, North Carolina 27599 (United States); Bromberg, Philip A. [Center for Environmental Medicine, Asthma, and Lung Biology, University of North Carolina, Chapel Hill, North Carolina 27599 (United States)]|[Department of Medicine, University of North Carolina, Chapel Hill, North Carolina 27599 (United States); Peden, David B. [Center for Environmental Medicine, Asthma, and Lung Biology, University of North Carolina, Chapel Hill, North Carolina 27599 (United States)]|[Department of Pediatrics, University of North Carolina, Chapel Hill, North Carolina 27599 (United States)]|[Department of Medicine, University of North Carolina, Chapel Hill, North Carolina 27599 (United States)

    2008-04-15

    CD40 is a costimulatory molecule linking innate and adaptive immune responses to bacterial stimuli, as well as a critical regulator of functions of other costimulatory molecules. The mechanisms regulating lipopolysaccharide (LPS)-induced CD40 expression have not been adequately characterized in human monocytic cells. In this study we used a human monocytic cell line, THP-1, to investigate the possible mechanisms of CD40 expression following LPS exposure. Exposure to LPS resulted in a dose- and time-dependent increase in CD40 expression. Further studies using immunoblotting and pharmacological inhibitors revealed that mitogen-activated protein kinases (MAPKs) and NF{kappa}B were activated by LPS exposure and involved in LPS-induced CD40 expression. Activation of MAPKs was not responsible for LPS-induced NF{kappa}B activation. TLR4 was expressed on THP-1 cells and pretreatment of cells with a Toll-like receptor 4 (TLR4) neutralizing antibody (HTA125) significantly blunted LPS-induced MAPK and NF{kappa}B activation and ensuing CD40 expression. Additional studies with murine macrophages expressing wild type and mutated TLR4 showed that TLR4 was implicated in LPS-induced ERK and NF{kappa}B activation, and CD40 expression. Moreover, blockage of MAPK and NF{kappa}B activation inhibited LPS-induced TLR4 expression. In summary, LPS-induced CD40 expression in monocytic cells involves MAPKs and NF{kappa}B.

  9. Increasing Parental Involvement through Active Participation with Parents of Fifth Grade Students in an Integrated Mainstreamed Classroom.

    ERIC Educational Resources Information Center

    Roundtree, Johnny M.

    This practicum focused on the problem of lack of involvement of the parents of 32 mainstreamed fifth grade students with special learning needs. Evening workshops were conducted for parents and their at-risk, mainstreamed students in fifth grade. Sessions focused on the use of computers, manipulatives, make and take home instructional games, study…

  10. Models of Collaborative Supervision Involving Teacher Educators and School Personnel in New Roles and Activities via Collaborative Supervisory Teams.

    ERIC Educational Resources Information Center

    Kull, Judith A.; And Others

    This paper describes the collaborative process and outcomes from involving teacher educators and school personnel in school-based collaborative supervisory teams formed by clustering graduate-level preservice teaching interns in a number of elementary and secondary field sites. The school-university collaborative reflects key elements in the…

  11. Involvement of Trichoderma trichothecenes in the biocontrol activity and in the induction of plant defense related genes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Trichoderma species produce trichothecenes, most notably trichodermin and harzianum A (HA), by a biosynthetic pathway in which several of the involved proteins have significant differences in functionality, compared to their Fusarium orthologues. In addition, the genes encoding these proteins show a...

  12. The Memory-Impairing Effects of Septal GABA Receptor Activation Involve GABAergic Septo-Hippocampal Projection Neurons

    ERIC Educational Resources Information Center

    Krebs-Kraft, Desiree L.; Wheeler, Marina G.; Parent, Marise B.

    2007-01-01

    Septal infusions of the [gamma]-aminobutyric acid (GABA)[subscript A] agonist muscimol impair memory, and the effect likely involves the hippocampus. GABA[subscript A] receptors are present on the perikarya of cholinergic and GABAergic septo-hippocampal (SH) projections. The current experiments determined whether GABAergic SH projections are…

  13. Critical Pedagogy, Experiential Learning and Active Citizenship: A Freirean Perspective on Tenant Involvement in Housing Stock Transfers

    ERIC Educational Resources Information Center

    McCormack, John

    2008-01-01

    A key feature of housing policy in the UK is the transfer of affordable housing stock owned by local authorities to not-for-profit registered social landlords. Such transfers involve local authority tenants to varying degrees in the development and implementation of the transfer proposals. Reporting the findings of a series of interviews with…

  14. ASI Student Involvement Outcomes ASI Student Involvement Outcomes

    E-print Network

    de Lijser, Peter

    ASI Student Involvement Outcomes ASI Student Involvement Outcomes A student involved in the activities, programs, and services of the Associated Students, CSUF, Inc. develops and demonstrates achievement in the following (adopted from the University of Minnesota Student Success Outcomes

  15. Physical Activity and Reduced Risk of Incident Sporadic Colorectal Adenomas: Observational Support for Mechanisms Involving Energy Balance and Inflammation Modulation

    Microsoft Academic Search

    Keith G. Hauret; Roberd M. Bostick; Charles E. Matthews; James R. Hussey

    To investigate the role of physical activity, energy balance, and inflammation on the risk of incident sporadic colorectal adenoma, the authors conducted a community- and colonoscopy-based case-control study (n = 177 cases, n = 228 controls) in Winston-Salem and Charlotte, North Carolina, from 1995 to 1997. Participants reported energy intake by a semiquantitative food frequency questionnaire, daily physical activity levels

  16. The Role of Intentional Self Regulation, Lower Neighborhood Ecological Assets, and Activity Involvement in Youth Developmental Outcomes

    ERIC Educational Resources Information Center

    Urban, Jennifer Brown; Lewin-Bizan, Selva; Lerner, Richard M.

    2010-01-01

    Extracurricular activities provide a key context for youth development, and participation has been linked with positive developmental outcomes. Using data from the 4-H Study of Positive Youth Development (PYD), this study explored how the intentional self regulation ability of youth interacted with participation in extracurricular activities to…

  17. Colocalization of Ion Channels Involved in Frequency Selectivity and Synaptic Transmission at Presynaptic Active Zones of Hair Cells

    Microsoft Academic Search

    William M. Roberts; R. A. Jacobs; A. J. Hudspeth

    1990-01-01

    Calcium ions serve as intracellular messengers in 2 activities of hair cells: in conjunction with Ca*+-activated K+ channels, they produce the electrical resonance that tunes each cell to a specific frequency of stimulation, and they trigger the release of a chemical synaptic transmitter. Our experiments indicate that both of these functions are conducted within a region that extends a few

  18. GLP-2 rapidly activates divergent intracellular signaling pathways involved in intestinal cell survival and proliferation in neonatal piglets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We previously demonstrated the dose-dependent glucagon-like peptide (GLP)-2 activation of intracellular signals associated with increased epithelial cell survival and proliferation in the neonatal intestine. Our current aim was to quantify the acute, temporal GLP-2 activation of these key intracellu...

  19. Effects of pituitary adenylate cyclase polypeptide (PACAP) on extinction of active avoidance learning in rats: involvement of neurotransmitters

    Microsoft Academic Search

    Agnes Adamik; Gyula Telegdy

    2005-01-01

    The effects of PACAP-38 on the extinction of active avoidance learning were studied in rats. The action of transmitter mediation was followed by pretreating the animals with appropriate receptor antagonists.PACAP-38 administered into the lateral brain ventricle caused a transitory facilitation of the extinction of a learned active avoidance response at 3 and 6 h following extinction, which had returned to

  20. Extracurricular Activity Participation and the Acquisition of Developmental Assets: Differences between Involved and Noninvolved Canadian High School Students

    ERIC Educational Resources Information Center

    Forneris, Tanya; Camiré, Martin; Williamson, Robert

    2015-01-01

    In order to prepare students for adulthood and responsible citizenship, most high schools offer extracurricular activities designed to facilitate the learning of a wide range of competencies. The purpose of this study was to examine how participation in a single or a combination of extracurricular school activities for high school students may…

  1. Youth Activity Involvement, Neighborhood Adult Support, Individual Decision Making Skills, and Early Adolescent Delinquent Behaviors: Testing a Conceptual Model

    ERIC Educational Resources Information Center

    Crean, Hugh F.

    2012-01-01

    This study examines a cross-sectional structural equation model of participation in youth activities, neighborhood adult support, individual decision making skills, and delinquent behavior in urban middle school youths (n = 2611). Results indicate extracurricular activity participation had both direct and indirect associations with delinquent…

  2. Involvement of Prolonged Ras Activation in Thrombopoietin-Induced Megakaryocytic Differentiation of a Human Factor-Dependent Hematopoietic Cell Line

    Microsoft Academic Search

    ITARU MATSUMURA; KOICHI NAKAJIMA; HIROSHI WAKAO; SEISUKE HATTORI; KOJI HASHIMOTO; HIROYUKI SUGAHARA; TAKASHI KATO; HIROSHI MIYAZAKI; TOSHIO HIRANO; YUZURU KANAKURA

    1998-01-01

    Thrombopoietin (TPO) is a hematopoietic growth factor that plays fundamental roles is both megakaryo- poiesis and thrombopoiesis through binding to its receptor, c-mpl. Although TPO has been shown to activate various types of intracellular signaling molecules, such as the Janus family of protein tyrosine kinases, signal transducers and activators of transcription (STATs), and ras, the precise mechanisms underlying TPO- induced

  3. Involvement in Campus Activities and the Retention of First-Year College Students. The First-Year Experience Monograph Series.

    ERIC Educational Resources Information Center

    Skipper, Tracy L., Ed.; Argo, Roxanne, Ed.

    The chapters of this monograph offer insights into educationally purposeful out-of-class activities and the impact they have on the student experience. It also provides future directions for the campus activities field and identifies ways to improve the educational experience of first-year students to enhance their scholarly experience and to…

  4. Interferon-? priming is involved in the activation of arginase by oligodeoxinucleotides containing CpG motifs in murine macrophages

    PubMed Central

    Liscovsky, Miriam V; Ranocchia, Romina P; Gorlino, Carolina V; Alignani, Diego O; Morón, Gabriel; Maletto, Belkys A; Pistoresi-Palencia, María C

    2009-01-01

    Recognition of microbial products by macrophages (M?) stimulates an inflammatory response and plays a critical role in directing the host immune response against infection. In the present work, we showed for the first time that synthetic oligodeoxynucleotides containing unmethylated cytosine guanine motifs (CpG) are able to stimulate, in the presence of interferon-? (IFN-?), both arginase and inducible nitric oxide synthase (iNOS) in murine M?. Unexpectedly, IFN-?, a cytokine believed to be an inhibitor of arginase activity, intervened in the activation of this enzyme. A significant increase in arginase activity was observed upon a short pre-incubation (1 hr) with IFN-? and subsequent CpG stimulation. Therefore, a very interesting observation of this study was that the CpG-mediated arginase activity is dependent on IFN-? priming. The increase in arginase activity as a result of stimulation with CpG plus IFN-?was correlated with augmented expression of the arginase II isoform. The use of pharmacological specific inhibitors revealed that arginase activity was dependent on p38 mitogen-activated protein kinase (MAPK) and extracellular signal-regulated protein kinase (ERK), but independent of c-Jun N-terminal kinase (JNK) activation. This report reveals a singular effect of the combination of CpG and IFN-?, one of the mayor cytokines produced in response to CpG administration in vivo. PMID:18800985

  5. Involvement of cAMP/EPAC/TRPM2 activation in glucose- and incretin-induced insulin secretion.

    PubMed

    Yosida, Masashi; Dezaki, Katsuya; Uchida, Kunitoshi; Kodera, Shiho; Lam, Nien V; Ito, Kiyonori; Rita, Rauza S; Yamada, Hodaka; Shimomura, Kenju; Ishikawa, San-e; Sugawara, Hitoshi; Kawakami, Masanobu; Tominaga, Makoto; Yada, Toshihiko; Kakei, Masafumi

    2014-10-01

    In pancreatic ?-cells, closure of the ATP-sensitive K(+) (K(ATP)) channel is an initial process triggering glucose-stimulated insulin secretion. In addition, constitutive opening of background nonselective cation channels (NSCCs) is essentially required to effectively evoke depolarization as a consequence of K(ATP) channel closure. Thus, it is hypothesized that further opening of NSCC facilitates membrane excitability. We identified a class of NSCC that was activated by exendin (ex)-4, GLP-1, and its analog liraglutide at picomolar levels. This NSCC was also activated by increasing the glucose concentration. NSCC activation by glucose and GLP-1 was a consequence of the activated cAMP/EPAC-mediated pathway and was attenuated in TRPM2-deficient mice. The NSCC was not activated by protein kinase A (PKA) activators and was activated by ex-4 in the presence of PKA inhibitors. These results suggest that glucose- and incretin-activated NSCC (TRPM2) works in concert with closure of the KATP channel to effectively induce membrane depolarization to initiate insulin secretion. The current study reveals a new mechanism for regulating electrical excitability in ?-cells and for mediating the action of glucose and incretin to evoke insulin secretion, thereby providing an innovative target for the treatment of type 2 diabetes. PMID:24824430

  6. Cocoa protective effects against abnormal fat storage and oxidative stress induced by a high-fat diet involve PPAR? signalling activation.

    PubMed

    Fidaleo, Marco; Fracassi, Anna; Zuorro, Antonio; Lavecchia, Roberto; Moreno, Sandra; Sartori, Claudia

    2014-11-01

    A high-fat (HF) diet increases lipid storage and oxidative stress in mouse liver and this process seems to be mediated by Peroxisome Proliferator-Activated Receptor ? (PPAR?). In this study we evaluated the protective effect of cocoa against hepatic steatosis induced by a HF diet. The HF diet down-regulated PPAR? expression and turned off PPAR?-signalling, deregulated the ?-oxidation (?-Ox) system and catalase (CAT) activity, increased fat storage, reduced expression of enzymatic activity involved in oxidative defence in the liver and doubled the weight gain per calorie consumed compared to animals under the normal diet. In contrast, cocoa improved hepatic ?-Ox, activated PPAR?-signalling and up-regulated both gene and protein expression of SOD1. Moreover, when co-administered with the HF diet, cocoa treatment counteracted lipid storage in the liver, improved the lipid-metabolizing activity and oxidative stress defences and normalized the weight gain per calorie consumed. PMID:25214316

  7. 5-Aminoimidazole-4-carboxamide riboside induces apoptosis in Jurkat cells, but the AMP-activated protein kinase is not involved.

    PubMed Central

    López, José M; Santidrián, Antonio F; Campàs, Clara; Gil, Joan

    2003-01-01

    5-Aminoimidazole-4-carboxamide (AICA) riboside, a precursor of purine nucleotide biosynthesis, induces apoptosis in Jurkat cells. Incorporation of AICAriboside into the cells is necessary for this effect since addition of nitrobenzylthioinosine, a nucleoside-transport inhibitor, completely protects Jurkat cells from apoptosis. Adenosine, but not other nucleosides, also protects Jurkat cells from AICAriboside-induced apoptosis. The apoptotic effect is caspase-dependent since caspases 9 and 3 are activated and the caspase inhibitor benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (Z-VAD.fmk) blocks apoptosis. Furthermore, AICAriboside induces mitochondrial cytochrome c release. AICAriboside, when phosphorylated to AICAribotide (ZMP), is a specific activator of the AMP-activated protein kinase (AMPK) in certain cell types. However, AICAriboside does not activate AMPK in Jurkat cells. Moreover, 5-iodotubercidin, an inhibitor of AICAriboside phosphorylation, does not inhibit apoptosis in Jurkat cells. These results indicate that AICAriboside induces apoptosis independently of ZMP synthesis and AMPK activation in Jurkat cells. PMID:12452797

  8. A Ca2+-activated protease possibly involved in myofibrillar protein turnover. Subcellular localization of the protease in porcine skeletal muscle.

    PubMed

    Reville, W J; Goll, D E; Stromer, M H; Robson, R M; Dayton, W R

    1976-07-01

    A study was done to determine whether the Ca2+-activated muscle protease (CAF) that removes Z disks from myofibrils in the presence of Ca2+ is located in a sedimentable subcellular organelle. Porcine skeletal muscle cells were diced finely with a scalpel and were suspended in 0.25 M sucrose, 4 mM EDTA with a VIRTIS homogenizer. Filtration of the suspended muscle through four layers of cheesecloth removed most of the myofibrils and stromal protein. Nuclear (1,000 gavg for 15 min), mitochondrial-microsomal (50,000 gavg for 60 min), and supernatant fractions were assayed for succinic dehydrogenase, acid ribonuclease, cathepsin D, and CAF activities. Approximately 96% of total succinic dehydrogenase activity, 81% of cathepsin D activity, and 45% of acid ribonuclease activity, but only 14% of total CAF activity, were found in the nuclear and mitochondrial-microsomal fractions. Cathepsin D activity in the nuclear and mitochondrial-microsomal fractions was decreased if assays were done without prior treatment to rupture membranous structures; hence, our cell rupture and homogenization procedures preserved some intact lysosomal organelles. The results indicate that the small amount of CAF activity in the nuclear and mitochondrial-microsomal fractions was due to contamination by supernate and that CAF is not located in a membrane-bounded subcellular particle. Because CAF is active at the intracellular pH and temperature of living skeletal muscle cells and is in direct contact with the cytoplasm of muscle cells, its activity must be regulated by intracellular cellular Ca2+ concentration to prevent continuous and indiscriminate degradation of myofibrils. PMID:945276

  9. Rapamycin-sensitive mTORC1 signaling is involved in physiological primordial follicle activation in mouse ovary.

    PubMed

    Tong, Yuanyuan; Li, Fei; Lu, Yi; Cao, Yanlan; Gao, Jimin; Liu, Jianghuai

    2013-12-01

    In mammals, resting female oocytes reside in primordial ovarian follicles. An individual primordial follicle may stay quiescent for a protracted period of time before initiating follicular growth, which is also termed “activation.” Female reproductive capacity is sustained by the gradual, streamlined activation of the entire population of primordial follicles, but this process also results in reproductive senescence in older animals. Based on the recent findings that genetically triggered, excessive mammalian target of rapamycin complex 1 (mTORC1) activation in mouse oocytes leads to accelerated primordial follicle activation, we examined the necessity of mTORC1 signaling in physiological primordial follicle activation. We found that induction of oocyte mTORC1 activity is associated with early follicular growth in neonatal mouse ovaries. Pharmacological inhibition of mTORC1 activity in vivo by rapamycin treatment leads to a marked, but partial, suppression of primordial follicle activation. The suppressive effect of rapamycin on primordial follicle activation was reproduced in cultured ovaries. While rapamycin did not apparently affect several plausible cellular targets in neonatal mouse ovaries, such as mTORC2, AKT, or cyclin-dependent kinase (CDK) inhibitor p27-KIP1, its inhibitory effect on Cyclin A2 gene expression implies that mTORC1 signaling in oocytes may engage a Cyclin A/CDK regulatory network that promotes primordial follicle activation. The current work strengthens the concept that mTORC1-dependent events in the oocytes of primordial follicles may represent potential targets for intervention in humans to slow the depletion of the ovarian reserve. PMID:24123525

  10. Autophagy is involved in anti-viral activity of pentagalloylglucose (PGG) against Herpes simplex virus type 1 infection in vitro

    SciTech Connect

    Pei, Ying, E-mail: peiying-19802@163.com [Biomedicine Research and Development Center of Jinan University, Guangzhou, Guangdong 510632 (China)] [Biomedicine Research and Development Center of Jinan University, Guangzhou, Guangdong 510632 (China); Chen, Zhen-Ping, E-mail: 530670663@qq.com [Biomedicine Research and Development Center of Jinan University, Guangzhou, Guangdong 510632 (China)] [Biomedicine Research and Development Center of Jinan University, Guangzhou, Guangdong 510632 (China); Ju, Huai-Qiang, E-mail: 344464448@qq.com [Biomedicine Research and Development Center of Jinan University, Guangzhou, Guangdong 510632 (China)] [Biomedicine Research and Development Center of Jinan University, Guangzhou, Guangdong 510632 (China); Komatsu, Masaaki, E-mail: komatsu-ms@igakuken.or.jp [Laboratory of Frontier Science, Tokyo Metropolitan Institute of Medical Science, Bunkyo-ku, Tokyo 113-8613 (Japan)] [Laboratory of Frontier Science, Tokyo Metropolitan Institute of Medical Science, Bunkyo-ku, Tokyo 113-8613 (Japan); Ji, Yu-hua, E-mail: tjyh@jnu.edu.cn [Institute of Tissue Transplantation and Immunology, College of Life Science and Technology, Jinan University, Guangzhou 510632 (China)] [Institute of Tissue Transplantation and Immunology, College of Life Science and Technology, Jinan University, Guangzhou 510632 (China); Liu, Ge, E-mail: lggege_15@hotmail.com [Division of Molecular Pharmacology of Infectious agents, Department of Molecular Microbiology and Immunology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8521 (Japan)] [Division of Molecular Pharmacology of Infectious agents, Department of Molecular Microbiology and Immunology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8521 (Japan); Guo, Chao-wan, E-mail: chaovan_kwok@hotmail.com [Division of Molecular Pharmacology of Infectious agents, Department of Molecular Microbiology and Immunology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8521 (Japan)] [Division of Molecular Pharmacology of Infectious agents, Department of Molecular Microbiology and Immunology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8521 (Japan); Zhang, Ying-Jun, E-mail: zhangyj@mail.kib.ac.cn [Kunming Institute of Botany, the Chinese Academy of Sciences, Yunnan, Kunming 650204 (China)] [Kunming Institute of Botany, the Chinese Academy of Sciences, Yunnan, Kunming 650204 (China); Yang, Chong-Ren, E-mail: cryang@mail.kib.ac.cn [Kunming Institute of Botany, the Chinese Academy of Sciences, Yunnan, Kunming 650204 (China)] [Kunming Institute of Botany, the Chinese Academy of Sciences, Yunnan, Kunming 650204 (China); Wang, Yi-Fei, E-mail: twang-yf@163.com [Biomedicine Research and Development Center of Jinan University, Guangzhou, Guangdong 510632 (China)] [Biomedicine Research and Development Center of Jinan University, Guangzhou, Guangdong 510632 (China); Kitazato, Kaio, E-mail: kkholi@msn.com [Division of Molecular Pharmacology of Infectious agents, Department of Molecular Microbiology and Immunology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8521 (Japan)] [Division of Molecular Pharmacology of Infectious agents, Department of Molecular Microbiology and Immunology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8521 (Japan)

    2011-02-11

    Research highlights: {yields} We showed PGG has anti-viral activity against Herpes simplex virus type 1 (HSV-1) and can induce autophgy. {yields} Autophagy may be a novel and important mechanism mediating PGG anti-viral activities. {yields} Inhibition of mTOR pathway is an important mechanism of induction of autophagy by PGG. -- Abstract: Pentagalloylglucose (PGG) is a natural polyphenolic compound with broad-spectrum anti-viral activity, however, the mechanisms underlying anti-viral activity remain undefined. In this study, we investigated the effects of PGG on anti-viral activity against Herpes simplex virus type 1 (HSV-1) associated with autophagy. We found that the PGG anti-HSV-1 activity was impaired significantly in MEF-atg7{sup -/-} cells (autophagy-defective cells) derived from an atg7{sup -/-} knockout mouse. Transmission electron microscopy revealed that PGG-induced autophagosomes engulfed HSV-1 virions. The mTOR signaling pathway, an essential pathway for the regulation of autophagy, was found to be suppressed following PGG treatment. Data presented in this report demonstrated for the first time that autophagy induced following PGG treatment contributed to its anti-HSV activity in vitro.

  11. Na+/H+ Exchanger Isoform 1 Induced Cardiomyocyte Hypertrophy Involves Activation of p90 Ribosomal S6 Kinase

    PubMed Central

    Jaballah, Maiy; Mohamed, Iman A.; Alemrayat, Bayan; Al-Sulaiti, Fatima; Mlih, Mohamed; Mraiche, Fatima

    2015-01-01

    Studies using pharmacological and genetic approaches have shown that increased activity/expression of the Na+/H+ exchanger isoform 1 (NHE1) play a critical role in the pathogenesis of cardiac hypertrophy. Despite the importance of NHE1 in cardiac hypertrophy, severe cerebrovascular side effects were associated with the use of NHE1 inhibitors when administered to patients with myocardial infarctions. p90 ribosomal S6 Kinase (RSK), a downstream regulator of the mitogen-activated protein kinase pathway, has also been implicated in cardiac hypertrophy. We hypothesized that RSK plays a role in the NHE1 induced cardiomyocyte hypertrophic response. Infection of H9c2 cardiomyoblasts with the active form of the NHE1 adenovirus induced hypertrophy and was associated with an increase in the phosphorylation of RSK (P<0.05). Parameters of hypertrophy such as cell area, protein content and atrial natriuretic mRNA expression were significantly reduced in H9c2 cardiomyoblasts infected with active NHE1 in the presence of dominant negative RSK (DN-RSK) (P<0.05). These results confirm that NHE1 lies upstream of RSK. Increased phosphorylation and activation of GATA4 at Ser261 was correlated with increased RSK phosphorylation. This increase was reversed upon inhibition of RSK or NHE1. These findings demonstrate for the first time that the NHE1 mediated hypertrophy is accounted for by increased activation and phosphorylation of RSK, which subsequently increased the phosphorylation of GATA4; eventually activating fetal gene transcriptional machinery. PMID:25830299

  12. Arsenic-induced alteration in intracellular calcium homeostasis induces head kidney macrophage apoptosis involving the activation of calpain-2 and ERK in Clarias batrachus

    SciTech Connect

    Banerjee, Chaitali [Immunobiology Laboratory, Department of Zoology, University of Delhi, Delhi 110 007 (India); Goswami, Ramansu [Immunobiology Laboratory, Department of Zoology, University of Delhi, Delhi 110 007 (India); Centre for Environmental Studies, Visva-Bharati University, Santiniketan 731 235 (India); Datta, Soma [Immunobiology Laboratory, Department of Zoology, University of Delhi, Delhi 110 007 (India); Rajagopal, R. [Gut Biology Laboratory, Department of Zoology, University of Delhi, Delhi 110 007 (India); Mazumder, Shibnath, E-mail: shibnath1@yahoo.co.in [Immunobiology Laboratory, Department of Zoology, University of Delhi, Delhi 110 007 (India)

    2011-10-01

    We had earlier shown that exposure to arsenic (0.50 {mu}M) caused caspase-3 mediated head kidney macrophage (HKM) apoptosis involving the p38-JNK pathway in Clarias batrachus. Here we examined the roles of calcium (Ca{sup 2+}) and extra-cellular signal-regulated protein kinase (ERK), the other member of MAPK-pathway on arsenic-induced HKM apoptosis. Arsenic-induced HKM apoptosis involved increased expression of ERK and calpain-2. Nifedipine, verapamil and EGTA pre-treatment inhibited the activation of calpain-2, ERK and reduced arsenic-induced HKM apoptosis as evidenced from reduced caspase-3 activity, Annexin V-FITC-propidium iodide and Hoechst 33342 staining. Pre-incubation with ERK inhibitor U 0126 inhibited the activation of calpain-2 and interfered with arsenic-induced HKM apoptosis. Additionally, pre-incubation with calpain-2 inhibitor also interfered with the activation of ERK and inhibited arsenic-induced HKM apoptosis. The NADPH oxidase inhibitor apocynin and diphenyleneiodonium chloride also inhibited ERK activation indicating activation of ERK in arsenic-exposed HKM also depends on signals from NADPH oxidase pathway. Our study demonstrates the critical role of Ca{sup 2+} homeostasis on arsenic-induced HKM apoptosis. We suggest that arsenic-induced alteration in intracellular Ca{sup 2+} levels initiates pro-apoptotic ERK and calpain-2; the two pathways influence each other positively and induce caspase-3 mediated HKM apoptosis. Besides, our study also indicates the role of ROS in the activation of ERK pathway in arsenic-induced HKM apoptosis in C. batrachus. - Highlights: > Altered Ca{sup 2+} homeostasis leads to arsenic-induced HKM apoptosis. > Calpain-2 plays a critical role in the process. > ERK is pro-apoptotic in arsenic-induced HKM apoptosis. > Arsenic-induced HKM apoptosis involves cross talk between calpain-2 and ERK.

  13. Signal transduction mechanisms involved in S100A4-induced activation of the transcription factor NF-?B

    PubMed Central

    2010-01-01

    Background The metastasis-promoting protein S100A4 activates the transcription factor NF-?B through the classical NF-?B activation pathway. The upstream signal transduction mechanisms leading to increased NF-?B activity are, however, incompletely characterized. Methods The human osteosarcoma cell line II-11b was stimulated with recombinant S100A4 in the presence or absence of inhibitors of common signal transduction pathways, and NF-?B activity was examined using a luciferase-based reporter assay and phosphorylation of I?B?. mRNA expression was analyzed by real-time RT-PCR, protein expression was examined by Western blotting and IKK activity was measured using an in vitro kinase assay. The role of upstream kinases and the cell surface receptor RAGE was investigated by overexpression of dominant negative proteins and by siRNA transfection. Results The Ser/Thr kinase inhibitors H-7 and staurosporine inhibited S100A4-induced I?B? phosphorylation and subsequent NF-?B activation. The protein tyrosine kinase inhibitor genistein and the phospholipase C inhibitor compound 48/80 had a partial inhibitory effect on I?B? phosphorylation, whereas inhibitors of protein kinase C, G-protein coupled receptors and PI 3-kinases had no effect on the level of phosphorylation. Interestingly, S100A4 treatment induced activating phosphorylations of IKK?/?, but neither H-7 nor staurosporine was able to significantly inhibit IKK activation. Dominant negative MEKK1 or NIK did not inhibit S100A4-induced NF-?B activity, and S100A4 stimulation did not influence AKT phosphorylation. Furthermore, diminished expression of the putative S100 protein receptor RAGE did not affect the observed phosphorylation of I?B?. Conclusions S100A4 activates NF-?B by inducing phosphorylation of IKK?/?, leading to increased I?B? phosphorylation. The Ser/Thr kinase inhibitors H-7 and staurosporine attenuated S100A4-induced NF-?B activation and inhibited IKK-mediated phosphorylation of I?B?. S100A4-induced NF-?B activation was independent of the putative S100 protein receptor RAGE and the Ser/Thr kinases MEKK1, NIK and AKT. These findings lead to increased understanding of S100A4 signaling, which may contribute to the identification of novel targets for anti-metastatic therapy. PMID:20507646

  14. Support for harmful treatment and reduction of empathy toward blacks: “Remnants” of stereotype activation involving Hurricane Katrina and “Lil’ Kim”

    Microsoft Academic Search

    James D. Johnson; Brad J. Bushman; John F. Dovidio

    2008-01-01

    Two experiments involving White participants tested the influence of media-based Black stereotypes on subsequent responses to Black and White persons-in-need. Experiment 1 showed that priming the “Black criminal” stereotype through exposure to photographs of Blacks looting after Hurricane Katrina produced greater application of the criminal stereotype and support for harmful treatment toward Black evacuees-in-need (i.e., police firing gun shots directly

  15. AMPA-receptor activation is involved in the antiamnesic effect of DM 232 (unifiram) and DM 235 (sunifiram)

    Microsoft Academic Search

    N. Galeotti; C. Ghelardini; A. Pittaluga; A. M. Pugliese; A. Bartolini; D. Manetti; M. N. Romanelli; F. Gualtieri

    2003-01-01

    DM 232 and DM 235 are novel antiamnesic compounds structurally related to ampakines. The involvement of AMPA receptors in the mechanism of action of DM 232 and DM 235 was, therefore, investigated in vivo and in vitro. Both compounds (0.1 mg\\/kg -1 i.p.) were able to reverse the amnesia induced by the AMPA receptor antagonist NBQX (30 mg\\/kg -1 i.p.) in the mouse passive avoidance test.

  16. Synthesis of a novel series of artemisinin dimers with potent anticancer activity involving Sonogashira cross-coupling reaction.

    PubMed

    Buragohain, Pori; Saikia, Bishwajit; Surineni, Naresh; Barua, Nabin C; Saxena, Ajit K; Suri, Nitasha

    2014-01-01

    A series of C-10 acetal artemisinin dimers were synthesized using Sonogashira cross-coupling reaction. All these novel semisynthetic artemisinin dimers exhibited excellent growth inhibitory activity against Lung A-549 human cancer cell line. PMID:24332623

  17. 78 FR 66968 - In the Matter of Landon E. Brittain; Order Prohibiting Involvement In NRC-Licensed Activities...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-07

    ...arising from behavioral observation, including, [[Page...to any questionable behavior patterns or activities...unusual or aberrant behavior. Despite these requirements...failed to report his observations regarding his coworker's unusual or aberrant behavior to his...

  18. A Novel Insight into the Mechanism of Pulmonary Hypertension Involving Caveolin-1 Deficiency and eNOS Activation

    PubMed Central

    Zhao, You-Yang; Malik, Asrar B.

    2010-01-01

    Severe pulmonary hypertension (PH) is characterized by a progressive increase in pulmonary vascular resistance and vascular remodeling leading to right heart failure and early death. Our recent studies employing the novel mouse model with genetic deletions of caveolin-1 (Cav1) and eNOS (NOS3) have demonstrated that persistent eNOS activation in Cav1?/? lungs results in tyrosine nitration of protein kinase G (PKG) and impairment of its activity, which thereby induces PH. The finding of eNOS activation and PKG nitration concomitant with Cav1 deficiency was recapitulated in lungs from patients with idiopathic pulmonary arterial hypertension. These data suggest targeting PKG nitration has potential value for the treatment of PH. Here, we will review the current knowledge about Cav1-regulated eNOS activity and its fundamental role in the pathogenesis of PH. PMID:20382348

  19. The Role of Intentional Self Regulation, Lower Neighborhood Ecological Assets, and Activity Involvement in Youth Developmental Outcomes

    Microsoft Academic Search

    Jennifer Brown Urban; Selva Lewin-Bizan; Richard M. Lerner

    2010-01-01

    Extracurricular activities provide a key context for youth development, and participation has been linked with positive developmental\\u000a outcomes. Using data from the 4-H Study of Positive Youth Development (PYD), this study explored how the intentional self\\u000a regulation ability of youth interacted with participation in extracurricular activities to affect PYD among adolescents living\\u000a in neighborhoods with relatively low ecological assets. In

  20. Transcriptional Activation by Gcn4p Involves Independent Interactions with the SWI\\/SNF Complex and the SRB\\/Mediator

    Microsoft Academic Search

    Krishnamurthy Natarajan; Belinda M Jackson; Heng Zhou; Fred Winston; Alan G Hinnebusch

    1999-01-01

    Mutations in three subunits of the SWI\\/SNF complex and in the Med2p subunit of the SRB\\/mediator of pol II holoenzyme impaired Gcn4p-activated transcription of HIS3 without reducing Gcn4p-independent transcription of this gene. Recombinant Gcn4p interacted with SWI\\/SNF and SRB\\/mediator subunits in cell extracts in a manner dependent on the same hydrophobic clusters in the Gcn4p activation domain; however, higher concentrations

  1. Proteolytic activation of the human epithelial sodium channel by trypsin IV and trypsin I involves distinct cleavage sites.

    PubMed

    Haerteis, Silke; Krappitz, Annabel; Krappitz, Matteus; Murphy, Jane E; Bertog, Marko; Krueger, Bettina; Nacken, Regina; Chung, Hyunjae; Hollenberg, Morley D; Knecht, Wolfgang; Bunnett, Nigel W; Korbmacher, Christoph

    2014-07-01

    Proteolytic activation is a unique feature of the epithelial sodium channel (ENaC). However, the underlying molecular mechanisms and the physiologically relevant proteases remain to be identified. The serine protease trypsin I can activate ENaC in vitro but is unlikely to be the physiologically relevant activating protease in ENaC-expressing tissues in vivo. Herein, we investigated whether human trypsin IV, a form of trypsin that is co-expressed in several extrapancreatic epithelial cells with ENaC, can activate human ENaC. In Xenopus laevis oocytes, we monitored proteolytic activation of ENaC currents and the appearance of ?ENaC cleavage products at the cell surface. We demonstrated that trypsin IV and trypsin I can stimulate ENaC heterologously expressed in oocytes. ENaC cleavage and activation by trypsin IV but not by trypsin I required a critical cleavage site (Lys-189) in the extracellular domain of the ?-subunit. In contrast, channel activation by trypsin I was prevented by mutating three putative cleavage sites (Lys-168, Lys-170, and Arg-172) in addition to mutating previously described prostasin (RKRK(178)), plasmin (Lys-189), and neutrophil elastase (Val-182 and Val-193) sites. Moreover, we found that trypsin IV is expressed in human renal epithelial cells and can increase ENaC-mediated sodium transport in cultured human airway epithelial cells. Thus, trypsin IV may regulate ENaC function in epithelial tissues. Our results show, for the first time, that trypsin IV can stimulate ENaC and that trypsin IV and trypsin I activate ENaC by cleavage at distinct sites. The presence of distinct cleavage sites may be important for ENaC regulation by tissue-specific proteases. PMID:24841206

  2. Improvement of alcoholic fermentation by calcium ions under enological conditions involves the increment of plasma membrane H + ATPase activity

    Microsoft Academic Search

    Jingyuan Li; Weidong Huang; Xiuqin Wang; Tian Tang; Zhaozhe Hua; Guoliang Yan

    2010-01-01

    The effect of Ca2+ on alcoholic fermentation and plasma membrane H+-ATPase activity of wine yeast under enological conditions were investigated in this study. The results showed that fermentation\\u000a rate, cell growth and ethanol production were improved by 0.5 and 1.5 mM Ca2+ supplementation, which correlated well with the increment of ATPase activity and protein levels. Considering the important\\u000a role of ATPase

  3. Direct Interaction between Nucleosome Assembly Protein 1 and the Papillomavirus E2 Proteins Involved in Activation of Transcription

    Microsoft Academic Search

    Manuela Rehtanz; Hanns-Martin Schmidt; Ursula Warthorst; Gertrud Steger

    2004-01-01

    Using a yeast two-hybrid screen, we identified human nucleosome assembly protein 1 (hNAP-1) as a protein interacting with the activation domain of the transcriptional activator encoded by papillomaviruses (PVs), the E2 protein. We show that the interaction between E2 and hNAP-1 is direct and not merely mediated by the transcriptional coactivator p300, which is bound by both proteins. Coexpression of

  4. Release of an acid phosphatase activity during lily pollen tube growth involves components of the secretory pathway

    Microsoft Academic Search

    Hala Ibrahim; Heidi Pertl; Klaus Pittertschatscher; Ezzat Fadl-Allah; Ahmed El-Shahed; Friedrich-Wilhelm Bentrup; Gerhard Obermeyer

    2002-01-01

    Summary.   An acid phosphatase (acPAse) activity was released during germination and tube growth of pollen of Lilium longiflorum Thunb. By inhibiting components of the secretory pathway, the export of the acPase activity was affected and tube growth\\u000a stopped. Brefeldin A (1??M) and cytochalasin D (1??M), which block the production and transport of secretory vesicles, respectively,\\u000a inhibited the acPase secretion. The

  5. Evidence of a retinoid signaling alteration involving the activator protein 1 complex in tumorigenic human bronchial epithelial cells and non-small cell lung cancer cells.

    PubMed

    Lee, H Y; Dawson, M I; Claret, F X; Chen, J D; Walsh, G L; Hong, W K; Kurie, J M

    1997-03-01

    Retinoids, including retinol and retinoic acid derivatives, inhibit the growth of normal human bronchial epithelial (HBE) cells. Using a lung carcinogenesis model consisting of normal, immortalized, and tumorigenic HBE cells, we showed previously that, compared to normal HBE cells, the tumorigenic HBE cell line 11701 is resistant to the growth-inhibitory effects of all-trans-retinoic acid (t-RA). Retinoid receptor function is preserved in tumorigenic 11701 cells, suggesting that other retinoid signaling components are altered. The activator protein 1 (AP-1) complex is a component of the retinoid signaling pathway and has demonstrated importance in cellular growth and differentiation. Therefore, we investigated whether AP-1 is involved in a retinoid signaling defect in tumorigenic 11701 cells and in retinoid-resistant non-small cell lung cancer (NSCLC) cell lines. We found that t-RA treatment inhibited AP-1 transcriptional activity in normal HBE cells but not in tumorigenic 11701 cells nor in the NSCLC cell lines Calu-1, Calu-6, SKMES-1, and ChaGo K1. We sought mechanisms for this retinoid signaling alteration involving AP-1 in tumorigenic 11701 cells. Basal AP-1 transcriptional activity; AP-1 DNA-binding activity; and the mRNA levels of c-fos, the AP-1 coactivator Jun activation domain-binding protein 1, and the retinoid receptor corepressor, the silencing mediator for retinoid and thyroid hormone receptors (SMRT), were lower in tumorigenic 11701 cells than in normal HBE cells. Transient transfection of tumorigenic 11701 cells with c-fos or CREB binding protein, which is a coactivator of AP-1 and retinoid receptors, enhanced basal AP-1 transcriptional activity but did not alter the effects of t-RA on AP-1 transcriptional activity. These findings provide evidence of a retinoid signaling alteration involving AP-1 in tumorigenic 11701 and NSCLC cells. Furthermore, the inhibitory effect of t-RA on AP-1 transcriptional activity was not restored in tumorigenic 11701 cells by transfection of c-fos, silencing mediator for retinoid and thyroid hormone receptors, Jun activation domain-binding protein 1, or CREB-binding protein, suggesting the involvement of other transcriptional coregulators in this retinoid signaling defect. PMID:9056670

  6. Kallikrein-related Peptidase-8 (KLK8) Is an Active Serine Protease in Human Epidermis and Sweat and Is Involved in a Skin Barrier Proteolytic Cascade

    PubMed Central

    Eissa, Azza; Amodeo, Vanessa; Smith, Christopher R.; Diamandis, Eleftherios P.

    2011-01-01

    Kallikrein-related peptidase-8 (KLK8) is a relatively uncharacterized epidermal protease. Although proposed to regulate skin-barrier desquamation and recovery, the catalytic activity of KLK8 was never demonstrated in human epidermis, and its regulators and targets remain unknown. Herein, we elucidated for the first time KLK8 activity in human non-palmoplantar stratum corneum and sweat ex vivo. The majority of stratum corneum and sweat KLK8 was catalytically active, displaying optimal activity at pH 8.5 and considerable activity at pH 5. We also showed that KLK8 is a keratinocyte-specific protease, not secreted by human melanocytes or dermal fibroblasts. KLK8 secretion increased significantly upon calcium induction of terminal keratinocyte differentiation, suggesting an active role for this protease in upper epidermis. Potential activators, regulators, and targets of KLK8 activity were identified by in vitro kinetic assays using pro-KLK8 and mature KLK8 recombinant proteins produced in Pichia pastoris. Mature KLK8 activity was enhanced by calcium and magnesium ions and attenuated by zinc ions and by autocleavage after Arg164. Upon screening KLK8 cleavage of a library of FRET-quenched peptides, trypsin-like specificity was observed with the highest preference for (R/K)(S/T)(A/V) at P1-P1?-P2?. We also demonstrated that KLK5 and lysyl endopeptidase activate latent pro-KLK8, whereas active KLK8 targets pro-KLK11, pro-KLK1, and LL-37 antimicrobial peptide activation in vitro. Together, our data identify KLK8 as a new active serine protease in human stratum corneum and sweat, and we propose regulators and targets that augment its involvement in a skin barrier proteolytic cascade. The implications of KLK8 elevation and hyperactivity in desquamatory and inflammatory skin disease conditions remain to be studied. PMID:20940292

  7. Pathways: Involvement of NF-?B, Activator Protein 1, and cAMP Response Element Binding Protein 1

    E-print Network

    Hydrogen peroxide (H 2O 2) has been shown to act as a second messenger that activates chemokine expression. In the present study, we investigated the mechanisms underlying this cellular regulation in the murine macrophage cell line B10R. We report that H 2O 2 increases mRNA expression of various chemokines, macrophage-inflammatory protein (MIP)-1?/CC chemokine ligand (CCL)3, MIP-1?/CCL4, MIP-2/CXC chemokine ligand 2, and monocyte chemoattractant protein-1/CCL2, by activating the extracellular signal-regulated kinase (ERK) pathway and the nuclear translocation of the transcription factors NF-?B, AP-1, and CREB. Blockage of the ERK pathway with specific inhibitors against mitogen-activated protein kinase kinase 1/2 and ERK1/ERK2 completely abolished both the H 2O 2-mediated chemokine up-regulation and the activation of all NF studied. Similarly, selective inhibition of cAMP and NF-?B strongly down-regulated the induction of all chemokine transcripts as well as CREB and NF-?B activation, respectively. Of interest, we detected a significant decrease of NF-?B, AP-1, and CREB DNA binding activities by reciprocal competition for these binding sites when either specific cold oligonucleotides (NF-?B, AP-1, and CREB) or Abs against various transcription factor subunits (p50, p65, c-Fos, Jun B, c-Jun, and CREB-1) were added. These findings indicate that cooperation between ERK- and cAMP-dependent pathways seems to be required to achieve the formation of an essential transcriptional factor complex for maximal H 2O 2-dependent chemokine modulation. Finally, experiments performed with actinomycin D suggest that H 2O 2-mediated MIP-1 ? mRNA up-regulation results from transcriptional control, whereas that of MIP-1?, MIP-2, and monocyte chemoattractant protein-1 is due to both gene transcription activation and mRNA posttranscriptional

  8. Anesthetic activation of central respiratory chemoreceptor neurons involves inhibition of a THIK-1-like background K+ current

    PubMed Central

    Lazarenko, Roman M.; Fortuna, Michal G.; Shi, Yingtang; Mulkey, Daniel K.; Takakura, Ana C.; Moreira, Thiago S.; Guyenet, Patrice G.; Bayliss, Douglas A.

    2010-01-01

    At surgical depths of anesthesia, inhalational anesthetics cause a loss of motor response to painful stimuli (i.e., immobilization) that is characterized by profound inhibition of spinal motor circuits. Yet, although clearly depressed, the respiratory motor system continues to provide adequate ventilation under these same conditions. Here, we show that isoflurane causes robust activation of CO2/pH-sensitive, Phox2b-expressing neurons located in the retrotrapezoid nucleus (RTN) of the rodent brainstem, in vitro and in vivo. In brainstem slices from Phox2b-eGFP mice, the firing of pH-sensitive RTN neurons was strongly increased by isoflurane, independent of prevailing pH conditions. At least two ionic mechanisms contributed to anesthetic activation of RTN neurons: activation of a Na+-dependent cationic current and inhibition of a background K+ current. Single cell RT-PCR analysis of dissociated GFP-labeled RTN neurons revealed expression of THIK-1 (K2P13.1), a channel that shares key properties with the native RTN current (i.e., suppression by inhalational anesthetics, weak rectification, inhibition by extracellular Na+, and pH-insensitivity). Isoflurane also increased firing rate of RTN chemosensitive neurons in urethane-anesthetized rats, again independent of CO2 levels. In these animals, isoflurane transiently enhanced activity of the respiratory system, an effect that was most prominent at low levels of respiratory drive and mediated largely by an increase in respiratory frequency. These data indicate that inhalational anesthetics cause activation of RTN neurons, which serve an important integrative role in respiratory control; the increased drive provided by enhanced RTN neuronal activity may contribute, in part, to maintaining respiratory motor activity under immobilizing anesthetic conditions. PMID:20610767

  9. Involvement of trypsin-digested silk peptides in the induction of RAW264.7 macrophage activation.

    PubMed

    Pyo, Kyoung-Ho; Kim, Min-Ki; Shin, Kwang-Soon; Chun, Hyang Sook; Shin, Eun-Hee

    2013-12-01

    The activation of macrophages by trypsin-digested silk peptides was investigated by considering CD1 lb and CD40 expression in the RAW264.7 cell, a murine macrophage. Silk protein hydrolysates were digested with trypsin, following by centrifugal purification using the Centriprep 30k concentrator. Trypsin-digested total silk peptides and its centrifugal fractions were tested for macrophage activation in vitro. The functional peptide of fractionated silk peptides was examined by LC/MS/MS analysis. Trypsin-digested and fractionated silk peptides of more than 30 kDa induced an increase in the activation markers CD1 lb and CD40 in RAW264.7 cells. These results are supported by morphological changes reflecting an increase in the number of dendrites in activated cells. The fractionated silk peptides examined by LC/MS/MS contained partial peptides of Bombyx mori fibroin. These results suggest that the activation of RAW264.7 macrophages may be induced not by sericin-derived peptides but by fibroin-derived ones. PMID:24555292

  10. Resveratrol upregulates Egr-1 expression and activity involving extracellular signal-regulated protein kinase and ternary complex factors.

    PubMed

    Rössler, Oliver G; Glatzel, Daniel; Thiel, Gerald

    2015-03-01

    Many intracellular functions have been attributed to resveratrol, a polyphenolic phytoalexin found in grapes and in other plants. Here, we show that resveratrol induces the expression of the transcription factor Egr-1 in human embryonic kidney cells. Using a chromosomally embedded Egr-1-responsive reporter gene, we show that the Egr-1 activity was significantly elevated in resveratrol-treated cells, indicating that the newly synthesized Egr-1 protein was biologically active. Stimulus-transcription coupling leading to the resveratrol-induced upregulation of Egr-1 expression and activity requires the protein kinases Raf and extracellular signal-regulated protein kinase ERK, while MAP kinase phosphatase-1 functions as a nuclear shut-off device that interrupts the signaling cascade connecting resveratrol stimulation with enhanced Egr-1 expression. On the transcriptional level, Elk-1, a key transcriptional regulator of serum response element-driven gene transcription, connects the intracellular signaling cascade elicited by resveratrol with transcription of the Egr-1 gene. These data were corroborated by the observation that stimulation of the cells with resveratrol increased the transcriptional activation potential of Elk-1. The SRE as well as the GC-rich DNA binding site of Egr-1 function as resveratrol-responsive elements. Thus, resveratrol regulates gene transcription via activation of the stimulus-regulated protein kinases Raf and ERK and the stimulus-responsive transcription factors TCF and Egr-1. PMID:25645941

  11. Promotion of testa rupture during garden cress germination involves seed compartment-specific expression and activity of pectin methylesterases.

    PubMed

    Scheler, Claudia; Weitbrecht, Karin; Pearce, Simon P; Hampstead, Anthony; Büttner-Mainik, Annette; Lee, Kieran J D; Voegele, Antje; Oracz, Krystyna; Dekkers, Bas J W; Wang, Xiaofeng; Wood, Andrew T A; Bentsink, Leónie; King, John R; Knox, J Paul; Holdsworth, Michael J; Müller, Kerstin; Leubner-Metzger, Gerhard

    2015-01-01

    Pectin methylesterase (PME) controls the methylesterification status of pectins and thereby determines the biophysical properties of plant cell walls, which are important for tissue growth and weakening processes. We demonstrate here that tissue-specific and spatiotemporal alterations in cell wall pectin methylesterification occur during the germination of garden cress (Lepidium sativum). These cell wall changes are associated with characteristic expression patterns of PME genes and resultant enzyme activities in the key seed compartments CAP (micropylar endosperm) and RAD (radicle plus lower hypocotyl). Transcriptome and quantitative real-time reverse transcription-polymerase chain reaction analysis as well as PME enzyme activity measurements of separated seed compartments, including CAP and RAD, revealed distinct phases during germination. These were associated with hormonal and compartment-specific regulation of PME group 1, PME group 2, and PME inhibitor transcript expression and total PME activity. The regulatory patterns indicated a role for PME activity in testa rupture (TR). Consistent with a role for cell wall pectin methylesterification in TR, treatment of seeds with PME resulted in enhanced testa permeability and promoted TR. Mathematical modeling of transcript expression changes in germinating garden cress and Arabidopsis (Arabidopsis thaliana) seeds suggested that group 2 PMEs make a major contribution to the overall PME activity rather than acting as PME inhibitors. It is concluded that regulated changes in the degree of pectin methylesterification through CAP- and RAD-specific PME and PME inhibitor expression play a crucial role during Brassicaceae seed germination. PMID:25429110

  12. Peroxisome Proliferator-Activated Receptor (PPAR) and PPAR\\/, but not PPAR, Modulate the Expression of Genes Involved in Cardiac Lipid Metabolism

    Microsoft Academic Search

    Andries J. Gilde; Karin A. J. M. van der Lee; Peter H. M. Willemsen; Giulia Chinetti; Feike R. van der Leij; Ger J. van der Vusse; Bart Staels; Marc van Bilsen

    Abstract—Long-chain fatty acids (FA) coordinately induce the expression of a panel of genes involved in cellular FA metabolism in cardiac muscle cells, thereby promoting their own metabolism. These effects are likely to be mediated by peroxisome,proliferator-activated receptors (PPARs). Whereas the significance of PPAR in FA-mediated expression has been demonstrated, the role of the PPAR\\/ and PPAR isoforms in cardiac lipid

  13. Mitogen-activated protein kinases and NF?B are involved in SP-A-enhanced responses of macrophages to mycobacteria

    Microsoft Academic Search

    Joseph P Lopez; David J Vigerust; Virginia L Shepherd

    2009-01-01

    BACKGROUND: Surfactant protein A (SP-A) is a C-type lectin involved in surfactant homeostasis as well as host defense in the lung. We have recently demonstrated that SP-A enhances the killing of bacillus Calmette-Guerin (BCG) by rat macrophages through a nitric oxide-dependent pathway. In the current study we have investigated the role of tyrosine kinases and the downstream mitogen-activated protein kinase

  14. Characterization of the molecular mechanism involved in the activation of hyaluronan synthetase by platelet-derived growth factor in human mesothelial cells.

    PubMed Central

    Heldin, P; Asplund, T; Ytterberg, D; Thelin, S; Laurent, T C

    1992-01-01

    The molecular mechanism involved in the stimulation of hyaluronan synthetase in normal human mesothelial cells was investigated. Exposure of mesothelial cells to platelet-derived growth factor (PDGF)-BB stimulated hyaluronan synthetase activity, measured in isolated membrane preparations, as well as hyaluronan secretion into the medium. The effect on hyaluronan synthetase was maximal after 6 h of treatment. In contrast, the stimulatory effect of transforming growth factor-beta 1 reached a maximum after 24 h. The stimulatory effect of PDGF-BB was inhibited by cycloheximide. The phosphotyrosine phosphatase inhibitor vanadate was found to stimulate hyaluronan synthetase activity, and to potentiate the effect of PDGF-BB. The protein kinase C (PKC) stimulator phorbol 12-myristate 13-acetate (PMA) also stimulated hyaluronan synthetase; furthermore, depletion of PKC by preincubation of the cells with PMA led to an inhibition of the PDGF-BB-induced stimulation of hyaluronan synthetase activity. Thus the PDGF-BB-induced stimulation of hyaluronan synthetase activity is dependent on protein synthesis and involves tyrosine phosphorylation and activation of PKC. PMID:1567364

  15. Involvement of Ca/sup 2 +//phospholipid-dependent C-kinase in phorbol ester-mediated activation of normal human T cell

    SciTech Connect

    Dirienzo, W.; Nel, A.E.; Lattanze, G.R.; Galbraith, R.M.

    1986-03-01

    C-kinase appears to be involved in biological responses of T cells, and phorbol myristate acetate (PMA) is a direct activator of this enzyme. In this study, reaction of T cells with PMA (0.1-50 ng/ml) showed a dose-dependent increase in /sup 3/H-thymidine incorporation; higher concentrations were toxic. C-kinase assays performed in parallel demonstrated sustained translocation of >99% of C-kinase activity from the cytosol to the detergent-soluble membrane fraction. Experiments were done in the presence of cyclosporine (CSA), and of polymyxin B (PMB) which also inhibits C-kinase. Both PMA and CSA caused profound and dose-dependent reduction in proliferation, with maximal inhibition of >70% and >90% respectively. Moreover, addition of PMB showed coordinate inhibition of C-kinase activity (>80% at 10 ..mu..M), whereas at similar concentrations inhibiting cell proliferation CSA had no detectable effect. These results indicate that PMA initiates activation and proliferation by stimulation of at least two distinct pathways, one of which involves C-kinase activation and is inhibited by PMB.

  16. T3-mediated activation of human T cells involves translocation of Ca/sup 2 +//phospholipid-dependent C-kinase

    SciTech Connect

    Galbraith, R.M.; Nel, A.E.; Dirienzo, W.; Canonica, W.; Goldschmidt-Clermont, P.J.

    1986-03-05

    Activation of human T cells with anti-73 involves increased intracellular (Ca/sup 2 +/) and phosphatidylinositol turnover. Quantitative assays of Ca/sup 2 +//phospholipid-dependent C-kinase showed high levels (40-60 pmol/..mu..g protein/min) in the cytosol of unstimulated T cells. After stimulation with anti-T3 (100 ng/ml), cytosol activity was rapidly reduced and membrane activity increased, consistent with translocation and activation of C-kinase. With the known C-kinase activator phorbol myristate acetate (PMA), translocation was also seen, but was more sustained and complete (>99% versus 40-60%). Qualitative analysis of endogenous phosphoproteins showed translocation of enzyme, and established the major substrates at MW 56, 42, 33, 24-25 and 20K. Labeling reactions were reduced in dose-dependent fashion by the C-kinase inhibitor polymyxin B (IC 14 ..mu..M), and addition to cultures caused >90% inhibition of proliferation (/sup 3/H-thymidine incorporation), even in the presence of optimal concentrations of IL-2 (4 ..mu../ml). Thus, C-kinase may be involved in T cell responses induced by modulation of the T3-Ti complex.

  17. CMYB1 Encoding a MYB Transcriptional Activator Is Involved in Abiotic Stress and Circadian Rhythm in Rice

    PubMed Central

    Duan, Min; Huang, Peng; Yuan, Xi; Chen, Hui; Zhang, Hongsheng

    2014-01-01

    Through analysis of cold-induced transcriptome, a novel gene encoding a putative MYB transcription factor was isolated and designated Cold induced MYB 1 (CMYB1). Tissue-specific gene expression analysis revealed that CMYB1 was highly expressed in rice stems and nodes. qRT-PCR assay indicated that CMYB1 was dramatically induced by cold stress (>100-folds) and induced by exogenous ABA and osmotic stress. Interestingly, CMYB1 showed rhythmic expression profile in rice leaves at different developmental stages. Subcellular localization assay suggested that CMYB1-GFP (green fluorescent protein) fusion protein was localized in the nuclei. Moreover, CMYB1 exhibited the transcriptional activation activity when transiently expressed in rice protoplast cells. Taken together, CMYB1 probably functions as a transcriptional activator in mediating stress and rhythm responsive gene expression in rice. PMID:24977183

  18. Microcystin-LR-caused ROS generation involved in p38 activation and tau hyperphosphorylation in neuroendocrine (PC12) cells.

    PubMed

    Meng, Guanmin; Liu, Jinghui; Lin, Shuyan; Guo, Zonglou; Xu, Lihong

    2015-03-01

    Microcystin-LR (MC-LR), a potent specific hepatotoxin produced by cyanobacteria, has recently been reported to show neurotoxicity. Our previous study demonstrated that MC-LR caused the reorganization of cytoskeleton architectures and hyperphosphorylation of the cytoskeletal-associated proteins tau and HSP27 in neuroendocrine PC12 cell line by direct PP2A inhibition and indirect p38 mitogen-activated protein kinase (MAPK) activation. It has been shown that oxidative stress is extensively associated with MC-LR toxicity, mainly resulting from an excessive production of reactive oxygen species (ROS). However, the mechanisms by which ROS mediates the cytotoxic action of MC-LR are unclear. In the present study, we investigated whether ROS might play a critical role in MC-LR-induced hyperphosphorylation of microtubule-associated protein tau and the activation of the MAPKs in PC12 cell line. The results showed that MC-LR had time- and concentration-dependent effects on ROS generation, p38-MAPK activation and tau phosphorylation. The time-course studies indicated similar biphasic changes in ROS generation and tau hyperphosphorylation, which started to increase within 1 h and reached the maximum level at 3 h followed by a decrease after prolonged treatment. Furthermore, pretreatment with the antioxidants, N-acetylcysteine and vitamin C, significantly decreased MC-LR-induced ROS generation and effectively attenuated p38-MAPK activation as well as tau hyperphosphorylation. Taken together, these findings suggest that ROS generation triggered by MC-LR is a key intracellular event that contributes to an induction of p38-MAPK activation and tau phosphorylation, and that blockade of this ROS-mediated redox-sensitive signal cascades may attenuate the toxic effects of MC-LR. PMID:24142891

  19. Anti-inflammatory activity of Pistacia lentiscus essential oil: involvement of IL-6 and TNF-alpha.

    PubMed

    Maxia, Andrea; Sanna, Cinzia; Frau, Maria Assunta; Piras, Alessandra; Karchuli, Manvendra Singh; Kasture, Veena

    2011-10-01

    The topical anti-inflammatory activity of essential oil of Pistacia lentiscus L. was studied using carrageenan induced rat paw edema and cotton pellet induced granuloma. The effect on serum tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) in rats inserted with cotton pellet was also investigated. On topical application, the oil exhibited a significant decrease in paw edema. The oil also inhibited cotton pellet-induced granuloma, and reduced serum TNF-alpha and IL-6. It can be concluded that the essential oil of Pistacia lentiscus reduces leukocyte migration to the damaged tissue and exhibits anti-inflammatory activity. PMID:22164803

  20. Highlights in basic autonomic neurosciences: Is an increase in sympathetic nerve activity involved in the development and maintenance of hypertension?

    PubMed

    Wehrwein, Erica; Barman, Susan M

    2014-02-01

    The 21st century has brought renewed energy to the field of neural control of the cardiovascular system with interest in assessing directly the role of sympathetic nerve activity (SNA) in initiating and/or maintaining an elevated level of arterial pressure in animal models of cardiovascular disease and in human subjects. Below is a review of some recent studies that use continuous nerve recordings of SNA to look at the time course of changes in activity as hypertension develops. These studies have advanced our understanding of the role of SNA in hypertension, but they also leave us wanting to know more. PMID:23933086

  1. Antioxidant activities of ethanol extracts and fractions of Crescentia cujete leaves and stem bark and the involvement of phenolic compounds

    PubMed Central

    2014-01-01

    Background Antioxidant compounds like phenols and flavonoids scavenge free radicals and thus inhibit the oxidative mechanisms that lead to control degenerative and other diseases. The aim of this study was to investigate the antioxidant activity in vitro, total phenolic and flavonoid contents in ethanol extracts and fractions of Crescentia cujete leaves and stem bark. Methods Crescentia cujete leaves and bark crude ethanol extract (CEE) and their partitionates petroleum ether (PEF), chloroform (CHF), ethyl acetate (EAF) and aqueous (AQF) were firstly prepared. Different established testing methods, such as 1, 1-diphenyl-2-picryl hydrazyl (DPPH) radical, ferric reducing power (FRP), and total antioxidant capacity (TAC) assays were used to detect the antioxidant activity. Further, the total yield, total phenolic (TPC) and total flavonoid contents (TFC) of CEE and all the fractions were determined. Ethanol extracts of both leaves and stem bark were also subjected to preliminary phytochemical screening to detect the presence of secondary metabolites, using standard phytochemical methods (Thin layer chromatography and spray reagents). Results Phytochemical screening of crude ethanol extract of both leaves and stem bark revealed the presence of steroids, flavonoids, saponins, tannins, glycosides and terpenoids. All the fractions and CEE of leaves and bark exhibited antioxidant activities, however, EAF of leaves showing the highest antioxidant activity based on the results of DPPH, FRP and TAC assay tests. The above fraction has shown the significant DPPH scavenging activity (IC50?=?8.78 ?g/ml) when compared with standard ascorbic acid (IC50 =7.68 ?g/ml). The TAC and FRP activities increased with increasing crude extract/fractions content. The TPC (371.23?±?15.77 mg GAE/g extract) and TFC (144.64?±?5.82 mg QE/g extract) of EAF of leaves were found significantly higher as compared to other solvent fractions for both leaves and bark. TPC were highly correlated with the antioxidant activity (R2?=?0.9268 and 0.8515 in DPPH test for leaves and bark, respectively). Conclusion The results of the study show that leaves of C. cujete possesses significant free radical scavenging properties compared with stem bark and a clear correlation exists between the antioxidant activity and phenolic content. PMID:24495381

  2. OsPT2, a phosphate transporter, is involved in the active uptake of selenite in rice

    PubMed Central

    Zhang, Lianhe; Hu, Bin; Li, Wei; Che, Ronghui; Deng, Kun; Li, Hua; Yu, Feiyan; Ling, Hongqing; Li, Youjun; Chu, Chengcai

    2014-01-01

    Selenite is a predominant form of selenium (Se) available to plants, especially in anaerobic soils, but the molecular mechanism of selenite uptake by plants is not well understood. ltn1, a rice mutant previously shown to have increased phosphate (Pi) uptake, was found to exhibit higher selenite uptake than the wild-type in both concentration- and time-dependent selenite uptake assays. Respiratory inhibitors significantly inhibited selenite uptake in the wildtype and the ltn1 mutant, indicating that selenite uptake was coupled with H+ and energy-dependent. Selenite uptake was greatly enhanced under Pi-starvation conditions, suggesting that Pi transporters are involved in selenite uptake. OsPT2, the most abundantly expressed Pi transporter in the roots, is also significantly up-regulated in ltn1 and dramatically induced by Pi starvation. OsPT2-overexpressing and knockdown plants displayed significantly increased and decreased rates of selenite uptake, respectively, suggesting that OsPT2 plays a crucial role in selenite uptake. Se content in rice grains also increased significantly in OsPT2-overexpressing plants. These data strongly demonstrate that selenite and Pi share similar uptake mechanisms and that OsPT2 is involved in selenite uptake, which provides a potential strategy for breeding Se-enriched rice varieties. PMID:24491113

  3. Nuclear factor of activated T cell (NFAT) transcription proteins regulate genes involved in adipocyte metabolism and lipolysis

    SciTech Connect

    Holowachuk, Eugene W. [Mary Imogene Bassett Hospital, Research Institute, 1 Atwell Road, Cooperstown, NY 13326 (United States)]. E-mail: geneh@telenet.net

    2007-09-21

    NFAT involvement in adipocyte physiological processes was examined by treatment with CsA and/or GSK3{beta} inhibitors (Li{sup +} or TZDZ-8), which prevent or increase NFAT nuclear translocation, respectively. CsA treatment reduced basal and TNF{alpha}-induced rates of lipolysis by 50%. Adipocytes preincubated with Li{sup +} or TZDZ-8 prior to CsA and/or TNF{alpha}, exhibited enhanced basal rates of lipolysis and complete inhibition of CsA-mediated decreased rates of lipolysis. CsA treatment dramatically reduced the mRNA levels of adipocyte-specific genes (aP2, HSL, PPAR{gamma}, ACS and Adn), compared with control or TNF{alpha}-treatment, whereas Li{sup +} pretreatment blocked the inhibitory effects of CsA, and mRNA levels of aP2, HSL, PPAR{gamma}, and ACS were found at or above control levels. NFAT nuclear localization, assessed by EMSA, confirmed that CsA or Li{sup +} treatments inhibited or increased NFAT nuclear translocation, respectively. These results show that NFAT proteins in mature adipocytes participate in the transcriptional control of genes involved in adipocyte metabolism and lipolysis.

  4. The Use of Parent Involved Take-Home Science Activities during Student Teaching: Understanding the Challenges of Implementation

    ERIC Educational Resources Information Center

    Zarazinski, Jill

    2010-01-01

    The purpose of this study was to identify student teachers use and implementation of "Science in a Bag" when it was no longer a required course-based assessment. This take-home science activity acted as the elaboration component of the 5Es lesson teacher candidates designed and taught in the classroom, utilized household items, and directly…

  5. Extracellular Acid Block and Acid-enhanced Inactivation of the -activated Cation Channel TRPM5 Involve Residues in the

    E-print Network

    Liman, Emily

    they sense chemicals in the environment and discriminate the nutritious from the noxious. In mammals, taste for the detec- tion of bitter, sweet, and amino acid tastes. In heterolo- gous cell types it forms a nonselective cation channel that is activated by intracellular Ca2 . TRPM5 is likely to be part of the taste

  6. Pathogenic forms of tau inhibit kinesin-dependent axonal transport through a mechanism involving activation of axonal phosphotransferases.

    PubMed

    Kanaan, Nicholas M; Morfini, Gerardo A; LaPointe, Nichole E; Pigino, Gustavo F; Patterson, Kristina R; Song, Yuyu; Andreadis, Athena; Fu, Yifan; Brady, Scott T; Binder, Lester I

    2011-07-01

    Aggregated filamentous forms of hyperphosphorylated tau (a microtubule-associated protein) represent pathological hallmarks of Alzheimer's disease (AD) and other tauopathies. While axonal transport dysfunction is thought to represent a primary pathogenic factor in AD and other neurodegenerative diseases, the direct molecular link between pathogenic forms of tau and deficits in axonal transport remain unclear. Recently, we demonstrated that filamentous, but not soluble, forms of wild-type tau inhibit anterograde, kinesin-based fast axonal transport (FAT) by activating axonal protein phosphatase 1 (PP1) and glycogen synthase kinase 3 (GSK3), independent of microtubule binding. Here, we demonstrate that amino acids 2-18 of tau, comprising a phosphatase-activating domain (PAD), are necessary and sufficient for activation of this pathway in axoplasms isolated from squid giant axons. Various pathogenic forms of tau displaying increased exposure of PAD inhibited anterograde FAT in squid axoplasm. Importantly, immunohistochemical studies using a novel PAD-specific monoclonal antibody in human postmortem tissue indicated that increased PAD exposure represents an early pathogenic event in AD that closely associates in time with AT8 immunoreactivity, an early marker of pathological tau. We propose a model of pathogenesis in which disease-associated changes in tau conformation lead to increased exposure of PAD, activation of PP1-GSK3, and inhibition of FAT. Results from these studies reveal a novel role for tau in modulating axonal phosphotransferases and provide a molecular basis for a toxic gain-of-function associated with pathogenic forms of tau. PMID:21734277

  7. Pathogenic Forms of Tau Inhibit Kinesin-Dependent Axonal Transport through a Mechanism Involving Activation of Axonal Phosphotransferases

    PubMed Central

    Kanaan, Nicholas M.; Morfini, Gerardo A.; LaPointe, Nichole E.; Pigino, Gustavo F.; Patterson, Kristina R.; Song, Yuyu; Andreadis, Athena; Fu, Yifan; Brady, Scott T.; Binder, Lester I.

    2012-01-01

    Aggregated filamentous forms of hyperphosphorylated tau (a microtubule-associated protein) represent pathological hallmarks of Alzheimer’s disease (AD) and other tauopathies. While axonal transport dysfunction is thought to represent a primary pathogenic factor in AD and other neurodegenerative diseases, the direct molecular link between pathogenic forms of tau and deficits in axonal transport remain unclear. Recently, we demonstrated that filamentous, but not soluble, forms of wild-type tau inhibit anterograde, kinesin-based fast axonal transport (FAT) by activating axonal protein phosphatase 1 (PP1) and glycogen synthase kinase 3 (GSK3), independent of microtubule binding. Here, we demonstrate that amino acids 2–18 of tau, comprising a phosphatase-activating domain (PAD), are necessary and sufficient for activation of this pathway in axoplasms isolated from squid giant axons. Various pathogenic forms of tau displaying increased exposure of PAD inhibited anterograde FAT in squid axoplasm. Importantly, immunohistochemical studies using a novel PAD-specific monoclonal antibody in human postmortem tissue indicated that increased PAD exposure represents an early pathogenic event in AD that closely associates in time with AT8 immunoreactivity, an early marker of pathological tau. We propose a model of pathogenesis in which disease-associated changes in tau conformation lead to increased exposure of PAD, activation of PP1-GSK3, and inhibition of FAT. Results from these studies reveal a novel role for tau in modulating axonal phosphotransferases and provide a molecular basis for a toxic gain-of-function associated with pathogenic forms of tau. PMID:21734277

  8. The Role of Family and Community Involvement in the Development and Implementation of School Nutrition and Physical Activity Policy

    ERIC Educational Resources Information Center

    Kehm, Rebecca; Davey, Cynthia S.; Nanney, Marilyn S.

    2015-01-01

    Background: Although there are several evidence-based recommendations directed at improving nutrition and physical activity standards in schools, these guidelines have not been uniformly adopted throughout the United States. Consequently, research is needed to identify facilitators promoting schools to implement these recommendations. Therefore,…

  9. Calcium-independent CaMKII activity is involved in ginsenoside Rb1-mediated neuronal recovery after hypoxic damage

    Microsoft Academic Search

    Jin Kyu Park; Chang Joong Lee; Jong Oh Park; Sung-Ha Jin; Oh-Bin Kwon; Sung Ryong Ko; Sang Won Kim; Eun Jung Kang; Ji Hun Ko; Sang Myung Lee; Dong Hee Kim; Moo Ho Won

    2005-01-01

    Recent studies have indicated that Ginsenoside Rb1, one of the major components of ginseng root, may play an important role in protecting cells from damage. Here, we investigated the neuroprotective activity of Rb1 after hypoxic injury in young rats. About 50% animals were dead by exposing hypoxic condition three times in three consecutive days. Then, the pretreatment with Rb1 prior

  10. Evidence concerning the involvement of 5-hydroxytryptamine in the locomotor activity produced by amphetamine or tranylcypromine plus L-DOPA.

    PubMed Central

    Green, A R; Kelly, P H

    1976-01-01

    1 Pretreatment of rats with p-chlorophenylalanine (PCPA; 2 X 200 mg/kg) decreased the concentration of 5-hydroxytryptamine (5-HT) in the brain. It also decreased the locomotor activity produced by tranylcypromine plus L-DOPA administration 24 h after the second dose of PCPA. 2 Pretreatment with p-chloroamphetamine, which produced a similar decrease in brain 5-HT concentrations did not decrease the locomotor response to tranylcypromine and L-DOPA. 3 PCPA pretreatment decreased the rise in the concentration of DOPA and dopamine in the brain following tranylcypromine and L-DOPA, suggesting its effect on the dopamine-induced locomotor activity was the result of this drug diminishing dopamine formation in the brain, probably by inhibiting L-DOPA uptake. 4 The locomotor activity produced by tranylcypromine and L-DOPA was not decreased by pretreatment 6 h earlier with disulfiram (400 mg/kg). This argues against the locomotor activity being due to noradrenergic stimulation. 5 PCPA pretreatment did not alter amphetamine-induced stereotypy or the circling behaviour in unilateral nigro-striatal lesioned rats. PMID:1276533

  11. Involvement of receptor activator of NF?B ligand and tumor necrosis factor-? in bone destruction in rheumatoid arthritis

    Microsoft Academic Search

    E Romas; M. T Gillespie; T. J Martin

    2002-01-01

    Bone loss represents a major unsolved problem in rheumatoid arthritis (RA). The skeletal complications of RA consist of focal bone erosions and periarticular osteoporosis at sites of active inflammation, and generalized bone loss with reduced bone mass. New evidence indicates that osteoclasts are key mediators of all forms of bone loss in RA. TNF-? is one of the most potent

  12. Prelimbic but not infralimbic cortex is involved in the pressor response to chemoreflex activation in awake rats.

    PubMed

    Granjeiro, Erica M; Scopinho, América A; Corrêa, Fernando M A; Resstel, Leonardo B M

    2011-05-01

    The ventral portion of the medial prefrontal cortex comprises the prelimbic cortex (PL) and the infralimbic cortex (IL). Several studies have indicated that both the PL and the IL play an important role in cardiovascular control. Chemoreflex activation by systemic administration of potassium cyanide (KCN) evokes pressor and bradycardiac responses in conscious rats, in addition to an increase in respiratory frequency. We report here a comparison between the effects of pharmacological inhibition of PL and IL neurotransmission on blood pressure and heart rate responses evoked by chemoreflex activation using KCN (i.v.) in conscious rats. Bilateral microinjection of 200 nl of the unspecific synaptic blocker CoCl(2) (1 mm) into the PL evoked a significant attenuation of the pressor response, without affecting the chemoreflex-induced heart rate decrease. However, IL local synapse inhibition evoked no changes in cardiovascular responses induced by chemoreflex activation. Thus, our results suggest that the pressor but not the bradycardiac response to chemoreflex activation is, at least in part, mediated by local neurotransmission present in the PL cortex, without influence of the IL cortex. PMID:21335419

  13. Apoptosis induced by domoic acid in mouse cerebellar granule neurons involves activation of p38 and JNK MAP kinases.

    PubMed

    Giordano, G; Klintworth, H M; Kavanagh, T J; Costa, L G

    2008-05-01

    In mouse cerebellar granule neurons (CGNs) the marine neurotoxin domoic acid (DomA) induces neuronal cell death, either by apoptosis or by necrosis, depending on its concentration, with apoptotic damage predominating in response to low concentrations (100 nM). DomA-induced apoptosis is due to selective activation of AMPA/kainate receptors, and is mediated by DomA-induced oxidative stress, leading to mitochondrial dysfunction and activation of caspase-3. The p38 MAP kinase and the c-Jun NH2-terminal protein kinase (JNK) have been shown to be preferentially activated by oxidative stress. Here we report that DomA increases p38 MAP kinase and JNK phosphorylation, and that this effect is more pronounced in CGNs from Gclm (-/-) mice, which lack the modifier subunit of glutamate-cysteine ligase, have very low glutathione (GSH) levels, and are more sensitive to DomA-induced apoptosis than CGNs from wild-type mice. The increased phosphorylation of JNK and p38 kinase was paralleled by a decreased phosphorylation of Erk 1/2. The AMPA/kainate receptor antagonist NBQX, but not the NMDA receptor antagonist MK-801, prevents DomA-induced activation of p38 and JNK kinases. Several antioxidants (GSH ethyl ester, catalase and phenylbutylnitrone) also prevent DomA-induced phosphorylation of JNK and p38 MAP kinases. Inhibitors of p38 (SB203580) and of JNK (SP600125) antagonize DomA-induced apoptosis. These results indicate the importance of oxidative stress-activated JNK and p38 MAP kinase pathways in DomA-induced apoptosis in CGNs. PMID:18164102

  14. Apoptosis induced by domoic acid in mouse cerebellar granule neurons involves activation of p38 and JNK MAP kinases

    PubMed Central

    Giordano, G.; Klintworth, H.M.; Kavanagh, T.J.; Costa, L.G.

    2008-01-01

    In mouse cerebellar granule neurons (CGN) the marine neurotoxin domoic acid (DomA) induces neuronal cell death, either by apoptosis or by necrosis, depending on its concentration, with apoptotic damage predominating in response to low concentrations (100 nM). DomA-induced apoptosis is due to selective activation of AMPA/kainate receptors, and is mediated by DomA-induced oxidative stress, leading to mitochondrial dysfunction and activation of caspase-3. The p38 MAP kinase and the c-Jun NH2-terminal protein kinase (JNK) have been shown to be preferentially activated by oxidative stress. Here we report that DomA increases p38 MAP kinase and JNK phosphorylation, and that this effect is more pronounced in CGNs from Gclm (?/?) mice, which lack the modifier subunit of glutamate-cysteine ligase, have very low glutathione (GSH) levels, and are more sensitive to DomA-induced apoptosis than CGNs from wild-type mice. The increased phosphorylation of JNK and p38 kinase was paralleled by a decreased phosphorylation of Erk 1/2. The AMPA/kainate receptor antagonist NBQX, but not the NMDA receptor antagonist MK-801, prevents DomA-induced activation of p38 and JNK kinases. Several antioxidants (GSH ethyl ester, catalase, phenylbutylnitrone) also prevent DomA-induced phosphorylation of JNK and p38 MAP kinases. Inhibitors of p38 (SB203580) and of JNK (SP600125) antagonize DomA-induced apoptosis. These results indicate the importance of oxidative stress-activated JNK and p38 MAP kinase pathways in DomA-induced apoptosis in CGNs. PMID:18164102

  15. Transcriptional reporters for genes activated by cell wall stress through a non-catalytic mechanism involving Mpk1 and SBF

    PubMed Central

    Kim, Ki-Young; Levin, David E.

    2011-01-01

    The Mpk1 MAP kinase of the Cell Wall Integrity (CWI) signaling pathway induces transcription of the FKS2 gene in response to cell wall stress through a non-catalytic mechanism that involves stable association of Mpk1 with the Swi4 transcription factor. This dimeric complex binds to a Swi4 recognition site in the FKS2 promoter. The Swi6 transcription factor is also required to bind this ternary complex for transcription initiation to ensue. In this context, the Mlp1 pseudokinase serves a redundant function with Mpk1. We have identified three additional genes, CHA1, YLR042c, and YKR013w that are induced by cell wall stress through the same mechanism. We report on the behavior of several promoter-lacZ reporter plasmids designed to detect cell wall stress transcription through this pathway. PMID:20641022

  16. Gender and grade level differences in interest, perceived personal capacity, and involvement in technology and engineering-related activities

    NASA Astrophysics Data System (ADS)

    Weber, Katherine

    Society has become increasingly technological, demanding that all citizens have a level of technological literacy. In order for this to occur, both males and females must participate in technology-related activities to achieve an adequate level of technological literacy. Despite individual and organizational efforts, females continue to be underrepresented in STEM-related occupations. This is especially true in many engineering-related fields. Jolly, Campbell and Perlman (2004) devised the Engagement, Capacity, and Continuity (ECC) Trilogy. With each factor of the trilogy in place, Jolly et al. found that female representation increased in STEM. The purpose of this study was to identify whether Jolly, Campbell, and Perlman's (2004) Engagement, Capacity, and Continuity Trilogy could be utilized by teachers in technology and engineering program settings to examine their students' interest (engagement), perceived personal capacity (capacity), as well as participation in technology and engineering-related activities (continuity). This descriptive study surveyed 556 female and male middle school and high school students enrolled in Technology and Engineering classes. The results of this study revealed that when students indicated a high interest and a high perceived personal capacity, and when they participated in technology and engineering-related activities, they also indicated an interest in pursuing a career in engineering. The results also revealed that the male students continued to be encouraged by technology and engineering teachers, parents, and counselors to pursue a career in engineering more than female students. This startling finding should draw some concern; both males and females should be equally encouraged to consider engineering as a career. Technology and engineering teachers should implement activities that appeal to both males and females. Parents should encourage their daughters to participate in informal learning opportunities to nurture their daughters' interest in STEM-related areas. Counselors should gain an awareness of the scope and diversity of different engineering fields so they can advise both male and female students to consider careers in engineering. In order for the United States to be competitive and innovative at the global level, female representation and contributions in STEM fields must increase. Key Words: GENDER, ENGAGEMENT, INTEREST, PERCEIVED PERSONAL CAPACITY, TECHNOLOGY AND ENGINEERING ACTIVITIES, WISCONSIN, STEM, AFTERSCHOOL ACTIVITIES.

  17. Involvement of MAPK ERK Activation in Upregulation of Water Channel Protein Aquaporin 1 in a Mouse Model of Bell's Palsy.

    PubMed

    Fang, Fan; Liu, Cai-Yue; Zhang, Jie; Zhu, Lie; Qian, Yu-Xin; Yi, Jing; Xiang, Zheng-Hua; Wang, Hui; Jiang, Hua

    2015-05-01

    The aim of this study is to immunolocalize the aquaporin 1 water channel protein (AQP1) in Schwann cells of idiopathic facial nerve and explore its possible role during the development of facial palsy induced by herpes simplex virus type 1 (HSV-1). HSV-1 was inoculated into the surface of posterior auricle of mouse to establish a paralyzed animal model. In HSV-1-induced facial palsy mice, protein levels of AQP1 significantly increased on the 9th to 16th day after inoculation of HSV-1. The upregulation of AQP1 was closely related to the intratemporal facial nerve edema in facial nerve canal, which was also consistent with the symptom of facial palsy in mice. In a hypoxia model of Schwann cells in vitro, we found that U0126, an ERK antagonist, inhibited not only morphological changes of cultures Schwann cells but also upregulation of both AQP1 and phosphorylated ERK. Combined with increased phosphorylated ERK in HSV-1-induced facial palsy mice, we inferred that ERK MAPK pathway might also be involved in increased AQP1 in mouse model of Bell's palsy. Although the precise mechanism needs to be further explored, our findings suggest that AQP1 in Schwann cells of intratemporal facial nerve is involved in the evolution of facial palsy induced by HSV-1 and may play an important role in the pathogenesis of this disease. AQP1 might be a potential target, and the ERK antagonist U0126 could be a new drug for the treatment of HSV-1-induced Bell's palsy in an early stage. PMID:25527444

  18. The involvement of nitric oxide in the hemodynamic and metabolic activities of the brain and small intestine

    NASA Astrophysics Data System (ADS)

    Tolmasov, M.; Barbiro-Michaely, E.; Mayevsky, A.

    2009-02-01

    Nitric oxide is a mediator in many physiological processes including vasodilatation of blood vessels, neurotransmission and prevention of platelet aggregation. It has also a role in the pathophysiology of sepsis, hemorrhagic shock, various traumatic events and critical conditions involved with circulatory abnormalities. The last one is accompanied by blood flow redistribution and is considered to be the putative cause of altered oxygen metabolism in various pathophysiological conditions. The present study tested the involvement of NO in the brain as a vital organ versus the small intestine, a less vital organ using the non-specific nitric oxide synthase inhibitor L-NAME and exogenous NO donor - nitrite. The parameters that were simultaneously monitored in both organs included mean arterial blood pressure (MAP), tissue blood flow (TBF), using laser Doppler flowmetery and NADH fluorescence using the fluorometric technique. Three groups were tested. Group 1 - L-NAME +nitrite, group 2 - control L-NAME and group 3 - control nitrite. Following LNAME, MAP significantly increased and remained elevated through the entire experiment. TBF decreased in both organs with full recovery in the brain and no recovery in the intestine, whereas NADH showed no significant changes. Nitrite alone had no significant effect on the parameters in any of the organs. In group 1 the infusion of nitrite decreased the level of elevated MAP earlier induced by L-NAME. Nitrite also recovered the reduced TBF in the brain whereas it had no beneficial effect on intestinal blood flow indicating for its regulatory role in the brain but not in the intestine.

  19. Indoxyl sulfate-induced activation of (pro)renin receptor is involved in expression of TGF-?1 and ?-smooth muscle actin in proximal tubular cells.

    PubMed

    Saito, Shinichi; Shimizu, Hidehisa; Yisireyili, Maimaiti; Nishijima, Fuyuhiko; Enomoto, Atsushi; Niwa, Toshimitsu

    2014-05-01

    Activation of (pro)renin receptor (PRR) is involved in the progression of chronic kidney disease. However, the role of indoxyl sulfate, a uremic toxin, in the activation of PRR is not clear. The present study aimed to clarify the role of indoxyl sulfate in activation of PRR, in relation to renal expression of fibrotic genes. Renal expression of PRR and renin/prorenin was up-regulated in chronic kidney disease rats compared with normal rats, whereas AST-120 suppressed these expression by reducing serum levels of indoxyl sulfate. Furthermore, administration of indoxyl sulfate to normotensive and hypertensive rats increased renal expression of PRR and renin/prorenin. Indoxyl sulfate induced expression of PRR and prorenin in cultured human proximal tubular cells (HK-2 cells). Indoxyl sulfate-induced PRR expression was inhibited by small interfering RNAs of signal transducer and activator of transcription 3 (Stat3) and nuclear factor-?B p65 in proximal tubular cells. N-acetylcysteine, an antioxidant, and diphenyleneiodonium, an inhibitor of nicotinamide adenine dinucleotide phosphate oxidase, suppressed indoxyl sulfate-induced PRR expression in proximal tubular cells. N-acetylcysteine prevented indoxyl sulfate-induced phosphorylation of Stat3 in proximal tubular cells. PRR small interfering RNA inhibited indoxyl sulfate-induced expression of TGF-?1 and ?-smooth muscle actin in proximal tubular cells. Taken together, indoxyl sulfate-induced up-regulation of prorenin expression and activation of PRR through production of reactive oxygen species and activation of Stat3 and nuclear factor-?B play an important role in the expression of TGF-?1 and ?-smooth muscle actin in proximal tubular cells. Thus, indoxyl sulfate-induced activation of prorenin/PRR might be involved in renal fibrosis. PMID:24601883

  20. Structure of Ddn, the Deazaflavin-Dependent Nitroreductase from Mycobacterium tuberculosis Involved in Bioreductive Activation of PA-824

    PubMed Central

    Cellitti, Susan E.; Shaffer, Jennifer; Jones, David H.; Mukherjee, Tathagata; Gurumurthy, Meera; Bursulaya, Badry; Boshoff, Helena I.; Choi, Inhee; Nayyar, Amit; Lee, Yong Sok; Cherian, Joseph; Niyomrattanakit, Pornwaratt; Dick, Thomas; Manjunatha, Ujjini H.; Barry, Clifton E.; Spraggon, Glen; Geierstanger, Bernhard H.

    2012-01-01

    Summary Tuberculosis continues to be a global health threat, making bicyclic nitroimidazoles an important new class of therapeutics. A deazaflavin-dependent nitroreductase (Ddn) from Mycobacterium tuberculosis catalyzes the reduction of nitroimidazoles such as PA-824, resulting in intracellular release of lethal reactive nitrogen species. The N-terminal 30 residues of Ddn are functionally important but are flexible or access multiple conformations, preventing structural characterization of the full-length, enzymatically active enzyme. Several structures were determined of a truncated, inactive Ddn protein core with and without bound F420 deazaflavin coenzyme as well as of a catalytically competent homolog from Nocardia farcinica. Mutagenesis studies based on these structures identified residues important for binding of F420 and PA-824. The proposed orientation of the tail of PA-824 toward the N terminus of Ddn is consistent with current structure-activity relationship data. PMID:22244759

  1. The median preoptic nucleus exhibits circadian regulation and is involved in food anticipatory activity in rabbit pups.

    PubMed

    Moreno, María Luisa; Meza, Enrique; Ortega, Arturo; Caba, Mario

    2014-05-01

    Rabbit pups are a natural model to study food anticipatory activity (FAA). Recently, we reported that three areas in the forebrain - the organum vasculosum of lamina terminalis, median preoptic nucleus (MnPO) and medial preoptic area - exhibit activation during FAA. Here, we examined the PER1 protein profile of these three forebrain regions in both nursed and fasted subjects. We found robust PER1 oscillations in the MnPO in nursed subjects, with high PER1 levels during FAA that persisted in fasted subjects. In conclusion, our data indicate that periodic nursing is a strong signal for PER1 oscillations in MnPO and future experiments are warranted to explore the specific role of this area in FAA. PMID:24417519

  2. DOE technical standards list: Directory of DOE and contractor personnel involved in non-government standards activities

    SciTech Connect

    NONE

    1999-05-01

    The body of this document contains a listing of DOE employees and DOE contractors who have submitted form DOE F 1300.2, Record of Non-Government Standards Activity, which is attached to the end of this document. Additional names were added from rosters supplied by non-Government standards bodies. The committees or governing bodies in which the person participates is listed after each name. An asterisk preceding the committee notation indicates that the person has identified himself or herself as the DOE representative on that committee. Appendices to this document are also provided to sort the information by the parent employment organization, by non-Government standards activity, and by the proper names of the non-Government standards organizations and committees. DOE employees and contractors listed in this technical standards list are those recorded as of May 1, 1999.

  3. DOE technical standards list: Directory of DOE and contractor personnel involved in non-government standards activities

    SciTech Connect

    NONE

    1996-08-01

    The body of this document contains a listing of DOE employees and DOE contractors who have submitted form DOE F 1300.2, Record of Non-Government Standards Activity, which is attached to the end of this document and to DOE Order 1300.2A. Additional names were added from rosters supplied by non-Government standards bodies. The committees or governing bodies in which the person participates is listed after each name. An asterisk preceding the committee notation indicates that the person has identified himself or herself as the DOE representative on that committee. Appendices to this document are also provided to sort the information by the parent employment organization, by non-Government standards activity, and by the proper names of the non-Government standards organizations and committees. DOE employees and contractors listed in this TSL are those recorded as of July 1, 1996.

  4. Involvement of protein kinase C and protein kinase A in the muscarinic receptor signalling pathways mediating phospholipase C activation, arachidonic acid release and calcium mobilisation.

    PubMed

    May, L G; Johnson, S; Krebs, S; Newman, A; Aronstam, R S

    1999-03-01

    The involvement of protein kinase C (PKC) and protein kinase A (PKA) in cholinergic signalling in CHO cells expressing the M3 subtype of the muscarinic acetylcholine receptor was examined. Muscarinic signalling was assessed by measuring carbachol-induced activation of phospholipase C (PLC), arachidonic acid release, and calcium mobilisation. Carbachol activation of PLC was not altered by inhibition of PKC with chelerythrine chloride, bisindolylmaleimide or chronic treatment with phorbol myristate acetate (PMA). Activation of PKC by acute treatment with PMA was similarly without effect. In contrast, inhibition of PKC blocked carbachol stimulation of arachidonic acid release. Likewise, PKC inhibition resulted in a decreased ability of carbachol to mobilise calcium, whereas PKC activation potentiated calcium mobilisation. Inhibition of PKA with H89 or Rp-cAMP did not alter the ability of carbachol to activate PLC. Similarly, PKA activation with Sp-cAMP or forskolin had no effect on PLC stimulation by carbachol. Carbachol-mediated release of arachidonic acid was decreased by H89 but only slightly increased by forskolin. Forskolin also increased calcium mobilisation by carbachol. These results suggest a function for PKC and PKA in M3 stimulation of arachidonic acid release and calcium mobilisation but not in PLC activation. PMID:10353692

  5. Plasma-activated medium induces A549 cell injury via a spiral apoptotic cascade involving the mitochondrial-nuclear network.

    PubMed

    Adachi, Tetsuo; Tanaka, Hiromasa; Nonomura, Saho; Hara, Hirokazu; Kondo, Shin-ichi; Hori, Masaru

    2015-02-01

    Plasma medicine is a rapidly expanding new field of interdisciplinary research that combines physics, chemistry, biology, and medicine. Nonthermal atmospheric pressure plasma can be applied to living cells and tissues and has emerged as a novel technology for cancer therapy. Plasma has recently been shown to affect cells not only directly, but also by indirect treatment with previously prepared plasma-activated medium (PAM). The objective of this study was to demonstrate the inhibitory effects of PAM on A549 cell survival and elucidate the signaling mechanisms responsible for cell death. PAM maintained its ability to suppress cell viability for at least 1 week when stored at -80°C. The severity of PAM-triggered cell injury depended on the kind of culture medium used to prepare the PAM, especially that with or without pyruvate. Hydrogen peroxide (H2O2) and/or its derived or cooperating reactive oxygen species reduced the mitochondrial membrane potential, downregulated the expression of the antiapoptotic protein Bcl2, activated poly(ADP-ribose) polymerase-1, and released apoptosis-inducing factor from mitochondria with endoplasmic reticulum stress. However, the activation of caspase 3/7 and attenuation of cell viability by the addition of caspase inhibitor were not observed. The accumulation of adenine 5'-diphosphoribose as a product of the above reactions activated transient receptor potential melastatin 2, which elevated intracellular Ca(2+) levels and subsequently led to cell death. These results demonstrated that H2O2 and/or other reactive species in PAM disturbed the mitochondrial-nuclear network in cancer cells through a caspase-independent apoptotic pathway. Moreover, damage to the plasma membrane by H2O2-cooperating charged species not only induced apoptosis, but also increased its permeability to extracellular reactive species. These phenomena were also detected in PAM-treated HepG2 and MCF-7 cells. PMID:25433364

  6. Involvement of microRNA in the activation of Akt/PKB signaling in wood frog liver

    E-print Network

    Storey, Kenneth B.

    PIP3 PIP3 PIP3 PIP3 PIP3 PIP3 PIP3 Inactive Akt PH Kinase domainHM (By mTORC2) PDK1 Kinase domain PH p PIP3PIP2 PI3K PTEN Phosphoinositide 3-kinases phosphatase and tensin homolog PDK S473 Signaling Phosphoinositide 3-kinases mTORC1 p21, p27 FOXOs GLUT1/4 Activation of Akt - Phosphorylation AKT

  7. Mechanism of Ang II involvement in activation of NF-?B through phosphorylation of p65 during aging

    Microsoft Academic Search

    Ji Min Kim; Hyoung-Sam Heo; Young Mi Ha; Byeong Hyeok Ye; Eun Kyeong Lee; Yeon Ja Choi; Byung Pal Yu; Hae Young Chung

    Angiotensin II (Ang II), a major effector of the renin–angiotensin system, is now recognized as a pro-inflammatory mediator.\\u000a This Ang II signaling, which causes transcription of pro-inflammatory genes, is regulated through nuclear factor-?B (NF-?B).\\u000a At present, the molecular mechanisms underlying the effect of aging on Ang II signaling and NF-?B activation are not fully\\u000a understood. The purpose of this study

  8. Human Deoxyhypusine Hydroxylase, an Enzyme Involved in Regulating Cell Growth, Activates O2 with a Nonheme Diiron Center

    SciTech Connect

    Vu, V.; Emerson, J; Martinho, M; Kim, Y; Munck, E; Park, M; Que, Jr., L

    2009-01-01

    Deoxyhypusine hydroxylase is the key enzyme in the biosynthesis of hypusine containing eukaryotic translation initiation factor 5A (eIF5A), which plays an essential role in the regulation of cell proliferation. Recombinant human deoxyhypusine hydroxylase (hDOHH) has been reported to have oxygen- and iron-dependent activity, an estimated iron/holoprotein stoichiometry of 2, and a visible band at 630 nm responsible for the blue color of the as-isolated protein. EPR, Moessbauer, and XAS spectroscopic results presented herein provide direct spectroscopic evidence that hDOHH has an antiferromagnetically coupled diiron center with histidines and carboxylates as likely ligands, as suggested by mutagenesis experiments. Resonance Raman experiments show that its blue chromophore arises from a (e-1,2-peroxo)diiron(III) center that forms in the reaction of the reduced enzyme with O2, so the peroxo form of hDOHH is unusually stable. Nevertheless we demonstrate that it can carry out the hydroxylation of the deoxyhypusine residue present in the elF5A substrate. Despite a lack of sequence similarity, hDOHH has a nonheme diiron active site that resembles both in structure and function those found in methane and toluene monooxygenases, bacterial and mammalian ribonucleotide reductases, and stearoyl acyl carrier protein ?9-desaturase from plants, suggesting that the oxygen-activating diiron motif is a solution arrived at by convergent evolution. Notably, hDOHH is the only example thus far of a human hydroxylase with such a diiron active site.

  9. Cannabinoid CB2 receptor activation reduces mouse myocardial ischemia-reperfusion injury: involvement of cytokine\\/chemokines and PMN

    Microsoft Academic Search

    Clara Di Filippo; Francesco Rossi; Settimio Rossi; Michele D'Amico

    2003-01-01

    In this study, we have assessed the activation of the cannabinoid CB2 receptor (CB2-R) in a model of mouse myocardial ischemia\\/ reperfusion (I\\/R). The results show that treatment of animals with WIN55212-2, a CB1\\/CB2-R ago- nist, given 30 min before induction of I\\/R, signifi- cantly reduced the extent of infarct size (IS) in the area at risk, as measured 2.5

  10. Characterization of the Active Bacterial Community Involved in Natural Attenuation Processes in Arsenic-Rich Creek Sediments

    Microsoft Academic Search

    Odile Bruneel; Aurélie Volant; Sébastien Gallien; Bertrand Chaumande; Corinne Casiot; Christine Carapito; Amélie Bardil; Guillaume Morin; Gordon E. Brown Jr; Christian J. Personné; Denis Le Paslier; Christine Schaeffer; Alain Van Dorsselaer; Philippe N. Bertin; Françoise Elbaz-Poulichet; Florence Arsène-Ploetze

    2011-01-01

    Acid mine drainage of the Carnoulès mine (France) is characterized by acid waters containing high concentrations of arsenic\\u000a and iron. In the first 30 m along the Reigous, a small creek draining the site, more than 38% of the dissolved arsenic was\\u000a removed by co-precipitation with Fe(III), in agreement with previous studies, which suggest a role of microbial activities\\u000a in the

  11. I think therefore I am: Rest-related prefrontal cortex neural activity is involved in generating the sense of self.

    PubMed

    Gruberger, M; Levkovitz, Y; Hendler, T; Harel, E V; Harari, H; Ben Simon, E; Sharon, H; Zangen, A

    2015-05-01

    The sense of self has always been a major focus in the psychophysical debate. It has been argued that this complex ongoing internal sense cannot be explained by any physical measure and therefore substantiates a mind-body differentiation. Recently, however, neuro-imaging studies have associated self-referential spontaneous thought, a core-element of the ongoing sense of self, with synchronous neural activations during rest in the medial prefrontal cortex (PFC), as well as the medial and lateral parietal cortices. By applying deep transcranial magnetic stimulation (TMS) over human PFC before rest, we disrupted activity in this neural circuitry thereby inducing reports of lowered self-awareness and strong feelings of dissociation. This effect was not found with standard or sham TMS, or when stimulation was followed by a task instead of rest. These findings demonstrate for the first time a critical, causal role of intact rest-related PFC activity patterns in enabling integrated, enduring, self-referential mental processing. PMID:25778382

  12. Effects of Luteolin on Liver, Kidney and Brain in Pentylentetrazol-Induced Seizures: Involvement of Metalloproteinases and NOS Activities

    PubMed Central

    Birman, Hüsniye; Dar, Kadriye Akgün; Kapucu, Ay?egül; Acar, Samet; Üzüm, Gülay

    2012-01-01

    Objective: Flavonoids are an important group of recognized antioxidants in plants. Luteolin (LUT) is a natural flavonoid in the plant kingdom. This study was aimed to investigate the effects of the LUT in the liver, kidney and brain of pentylentetrazol (PTZ)-induced seizure and the relationship between nitric oxide synthases (iNOS, eNOS) and matrix metalloproteinases (MMP2, MMP9). Materials and Methods: LUT (10 mg/kg) was given intraperitoneally during two weeks prior to seizure induction. A single dose PTZ 80 mg/kg i.p. was administered and seizures were observed and evaluated with regard to latency, frequency and stage for one hour. Results: Seizure frequen cy after PTZ administration was significantly decreased in LUT pretreated rats (p<0.05). An increase of immunhistochemical reactions of iNOS and MMP2, but a decrease of eNOS activity, were observed in rat hippocampus and peripheral tissues during the PTZ induced seizures. LUT pretreatment reversed the iNOS and MMP2 activity to the control levels and significantly increased the eNOS activity (p<0.001). Conclusion: LUT seems to have an effective role in reducing the seizure frequency and a protective role on peripheral organ injury in animal models of seizure. The protective effect of LUT in seizures and the seizure induced peripheral tissue damage warrant further investigations. PMID:25206993

  13. Anti-biofilm activity of pseudoalteromonas haloplanktis tac125 against staphylococcus epidermidis biofilm: Evidence of a signal molecule involvement?

    PubMed

    Parrilli, E; Papa, R; Carillo, S; Tilotta, M; Casillo, A; Sannino, F; Cellini, A; Artini, M; Selan, L; Corsaro, M M; Tutino, M L

    2015-03-01

    Staphylococcus epidermidis is recognized as cause of biofilm-associated infections and interest in the development of new approaches for S. epidermidis biofilm treatment has increased. In a previous paper we reported that the supernatant of Antarctic bacterium Pseudoalteromonas haloplanktis TAC125 presents an anti-biofilm activity against S. epidermidis and preliminary physico-chemical characterization of the supernatant suggested that this activity is due to a polysaccharide. In this work we further investigated the chemical nature of the anti-biofilm P. haloplanktis TAC125 molecule. The production of the molecule was evaluated in different conditions, and reported data demonstrated that it is produced in all P. haloplanktis TAC125 biofilm growth stages, also in minimal medium and at different temperatures. By using a surface coating assay, the surfactant nature of the anti-biofilm compound was excluded. Moreover, a purification procedure was set up and the analysis of an enriched fraction demonstrated that the anti-biofilm activity is not due to a polysaccharide molecule but that it is due to small hydrophobic molecules that likely work as signal. The enriched fraction was also used to evaluate the effect on S. epidermidis biofilm formation in dynamic condition by BioFlux system. PMID:25816412

  14. Antiangiogenic activity of trabectedin in myxoid liposarcoma: involvement of host TIMP-1 and TIMP-2 and tumor thrombospondin-1.

    PubMed

    Dossi, Romina; Frapolli, Roberta; Di Giandomenico, Silvana; Paracchini, Lara; Bozzi, Fabio; Brich, Silvia; Castiglioni, Vittoria; Borsotti, Patrizia; Belotti, Dorina; Uboldi, Sarah; Sanfilippo, Roberta; Erba, Eugenio; Giavazzi, Raffaella; Marchini, Sergio; Pilotti, Silvana; D'Incalci, Maurizio; Taraboletti, Giulia

    2015-02-01

    Trabectedin is a marine natural product, approved in Europe for the treatment of soft tissue sarcoma and relapsed ovarian cancer. Clinical and experimental evidence indicates that trabectedin is particularly effective against myxoid liposarcomas where response is associated to regression of capillary networks. Here, we investigated the mechanism of the antiangiogenic activity of trabectedin in myxoid liposarcomas. Trabectedin directly targeted endothelial cells, impairing functions relying on extracellular matrix remodeling (invasion and branching morphogenesis) through the upregulation of the inhibitors of matrix metalloproteinases TIMP-1 and TIMP-2. Increased TIMPs synthesis by the tumor microenvironment following trabectedin treatment was confirmed in xenograft models of myxoid liposarcoma. In addition, trabectedin upregulated tumor cell expression of the endogenous inhibitor thrombospondin-1 (TSP-1, a key regulator of angiogenesis-dependent dormancy in sarcoma), in in vivo models of myxoid liposarcomas, in vitro cell lines and primary cell cultures from patients' myxoid liposarcomas. Chromatin Immunoprecipitation analysis showed that trabectedin displaced the master regulator of adipogenesis C/EBP? from the TSP-1 promoter, indicating an association between the up-regulation of TSP-1 and induction of adipocytic differentiation program by trabectedin. We conclude that trabectedin inhibits angiogenesis through multiple mechanisms, including directly affecting endothelial cells in the tumor microenvironment--with a potentially widespread activity--and targeting tumor cells' angiogenic activity, linked to a tumor-specific molecular alteration. PMID:24917554

  15. Tetrahydrocurcumin induces G2/M cell cycle arrest and apoptosis involving p38 MAPK activation in human breast cancer cells.

    PubMed

    Kang, Ning; Wang, Miao-Miao; Wang, Ying-Hui; Zhang, Zhe-Nan; Cao, Hong-Rui; Lv, Yuan-Hao; Yang, Yang; Fan, Peng-Hui; Qiu, Feng; Gao, Xiu-Mei

    2014-05-01

    Curcumin (CUR) is a major naturally-occurring polyphenol of Curcuma species, which is commonly used as a yellow coloring and flavoring agent in foods. In recent years, it has been reported that CUR exhibits significant anti-tumor activity in vivo. However, the pharmacokinetic features of CUR have indicated poor oral bioavailability, which may be related to its extensive metabolism. The CUR metabolites might be responsible for the antitumor pharmacological effects in vivo. Tetrahydrocurcumin (THC) is one of the major metabolites of CUR. In the present study, we examined the efficacy and associated mechanism of action of THC in human breast cancer MCF-7 cells for the first time. Here, THC exhibited significant cell growth inhibition by inducing MCF-7 cells to undergo mitochondrial apoptosis and G2/M arrest. Moreover, co-treatment of MCF-7 cells with THC and p38 MAPK inhibitor, SB203580, effectively reversed the dissipation in mitochondrial membrane potential (??m), and blocked THC-mediated Bax up-regulation, Bcl-2 down-regulation, caspase-3 activation as well as p21 up-regulation, suggesting p38 MAPK might mediate THC-induced apoptosis and G2/M arrest. Taken together, these results indicate THC might be an active antitumor form of CUR in vivo, and it might be selected as a potentially effective agent for treatment of human breast cancer. PMID:24593988

  16. Two negative cis-regulatory regions involved in fruit-specific promoter activity from watermelon (Citrullus vulgaris S.)

    PubMed Central

    Yin, Tao; Wu, Hanying; Zhang, Shanglong; Liu, Jingmei; Lu, Hongyu; Zhang, Lingxiao; Xu, Yong; Chen, Daming

    2009-01-01

    A 1.8?kb 5?-flanking region of the large subunit of ADP-glucose pyrophosphorylase, isolated from watermelon (Citrullus vulgaris S.), has fruit-specific promoter activity in transgenic tomato plants. Two negative regulatory regions, from –986 to –959 and from –472 to –424, were identified in this promoter region by fine deletion analyses. Removal of both regions led to constitutive expression in epidermal cells. Gain-of-function experiments showed that these two regions were sufficient to inhibit RFP (red fluorescent protein) expression in transformed epidermal cells when fused to the cauliflower mosaic virus (CaMV) 35S minimal promoter. Gel mobility shift experiments demonstrated the presence of leaf nuclear factors that interact with these two elements. A TCCAAAA motif was identified in these two regions, as well as one in the reverse orientation, which was confirmed to be a novel specific cis-element. A quantitative ?-glucuronidase (GUS) activity assay of stable transgenic tomato plants showed that the activities of chimeric promoters harbouring only one of the two cis-elements, or both, were ?10-fold higher in fruits than in leaves. These data confirm that the TCCAAAA motif functions as a fruit-specific element by inhibiting gene expression in leaves. PMID:19073962

  17. Transposon Mutagenesis of Probiotic Lactobacillus casei Identifies asnH, an Asparagine Synthetase Gene Involved in Its Immune-Activating Capacity

    PubMed Central

    Ito, Masahiro; Kim, Yun-Gi; Tsuji, Hirokazu; Takahashi, Takuya; Kiwaki, Mayumi; Nomoto, Koji; Danbara, Hirofumi; Okada, Nobuhiko

    2014-01-01

    Lactobacillus casei ATCC 27139 enhances host innate immunity, and the J1 phage-resistant mutants of this strain lose the activity. A transposon insertion mutant library of L. casei ATCC 27139 was constructed, and nine J1 phage-resistant mutants out of them were obtained. Cloning and sequencing analyses identified three independent genes that were disrupted by insertion of the transposon element: asnH, encoding asparagine synthetase, and dnaJ and dnaK, encoding the molecular chaperones DnaJ and DnaK, respectively. Using an in vivo mouse model of Listeria infection, only asnH mutant showed deficiency in their ability to enhance host innate immunity, and complementation of the mutation by introduction of the wild-type asnH in the mutant strain recovered the immuno-augmenting activity. AsnH protein exhibited asparagine synthetase activity when the lysozyme-treated cell wall extracts of L. casei ATCC 27139 was added as substrate. The asnH mutants lost the thick and rigid peptidoglycan features that are characteristic to the wild-type cells, indicating that AsnH of L. casei is involved in peptidoglycan biosynthesis. These results indicate that asnH is required for the construction of the peptidoglycan composition involved in the immune-activating capacity of L. casei ATCC 27139. PMID:24416179

  18. Involvement of Na+/K+ pump in fine modulation of bursting activity of the snail Br neuron by 10 mT static magnetic field.

    PubMed

    Nikoli?, Ljiljana; Todorovi?, Nataša; Zakrzewska, Joanna; Stani?, Marina; Rauš, Snežana; Kalauzi, Aleksandar; Jana?, Branka

    2012-07-01

    The spontaneously active Br neuron from the brain-subesophageal ganglion complex of the garden snail Helix pomatia rhythmically generates regular bursts of action potentials with quiescent intervals accompanied by slow oscillations of membrane potential. We examined the involvement of the Na(+)/K(+) pump in modulating its bursting activity by applying a static magnetic field. Whole snail brains and Br neuron were exposed to the 10-mT static magnetic field for 15 min. Biochemical data showed that Na(+)/K(+)-ATPase activity increased almost twofold after exposure of snail brains to the static magnetic field. Similarly, (31)P NMR data revealed a trend of increasing ATP consumption and increase in intracellular pH mediated by the Na(+)/H(+) exchanger in snail brains exposed to the static magnetic field. Importantly, current clamp recordings from the Br neuron confirmed the increase in activity of the Na(+)/K(+) pump after exposure to the static magnetic field, as the magnitude of ouabain's effect measured on the membrane resting potential, action potential, and interspike interval duration was higher in neurons exposed to the magnetic field. Metabolic pathways through which the magnetic field influenced the Na(+)/K(+) pump could involve phosphorylation and dephosphorylation, as blocking these processes abolished the effect of the static magnetic field. PMID:22534773

  19. Transposon mutagenesis of probiotic Lactobacillus casei identifies asnH, an asparagine synthetase gene involved in its immune-activating capacity.

    PubMed

    Ito, Masahiro; Kim, Yun-Gi; Tsuji, Hirokazu; Takahashi, Takuya; Kiwaki, Mayumi; Nomoto, Koji; Danbara, Hirofumi; Okada, Nobuhiko

    2014-01-01

    Lactobacillus casei ATCC 27139 enhances host innate immunity, and the J1 phage-resistant mutants of this strain lose the activity. A transposon insertion mutant library of L. casei ATCC 27139 was constructed, and nine J1 phage-resistant mutants out of them were obtained. Cloning and sequencing analyses identified three independent genes that were disrupted by insertion of the transposon element: asnH, encoding asparagine synthetase, and dnaJ and dnaK, encoding the molecular chaperones DnaJ and DnaK, respectively. Using an in vivo mouse model of Listeria infection, only asnH mutant showed deficiency in their ability to enhance host innate immunity, and complementation of the mutation by introduction of the wild-type asnH in the mutant strain recovered the immuno-augmenting activity. AsnH protein exhibited asparagine synthetase activity when the lysozyme-treated cell wall extracts of L. casei ATCC 27139 was added as substrate. The asnH mutants lost the thick and rigid peptidoglycan features that are characteristic to the wild-type cells, indicating that AsnH of L. casei is involved in peptidoglycan biosynthesis. These results indicate that asnH is required for the construction of the peptidoglycan composition involved in the immune-activating capacity of L. casei ATCC 27139. PMID:24416179

  20. Involvement of Manduca sexta peptidoglycan recognition protein-1 in the recognition of bacteria and activation of prophenoloxidase system

    PubMed Central

    Sumathipala, Niranji; Jiang, Haobo

    2010-01-01

    Although the importance of peptidoglycan recognition proteins (PGRPs) in detecting bacteria and promoting immunity is well recognized in Drosophila melanogaster and other insect species, such a role has not yet been experimentally established for PGRPs in the tobacco hornworm, Manduca sexta. In this study, we purified M. sexta PGRP1 from the baculovirus-insect cell expression system, tested its association with peptidoglycans and intact bacteria, and explored its possible link with the prophenoloxidase activation system in larval hemolymph. Sequence comparison suggested that PGRP1 is not an amidase and lacks residues for interacting with the carboxyl group of meso-diaminopimelic acid-peptidoglycans (DAP-PGs). M. sexta PGRP1 gene was constitutively expressed at a low level in fat body, and the mRNA concentration became much higher after an injection of Escherichia coli. Consistently, the protein concentration in larval plasma increased in a time-dependent manner after the immune challenge. Purified recombinant PGRP1 specifically bound to soluble DAP-PG of E. coli but not to soluble Lys-type PG of Staphylococcus aureus. In addition, this recognition protein completely bound to insoluble PGs from Micrococcus luteus, Bacillus megaterium and Bacillus subtilis, whereas its association with the bacterial cells was low even though their peptidoglycans are exposed on the cell surface. After PGRP1 had been added to plasma of naïve larvae in the absence of microbial elicitor, there was a concentration-dependent increase in prophenoloxidase activation. Phenoloxidase activity, as usual, increased after the plasma was incubated with peptidoglyans or bacterial cells. These increases became more prominent when insoluble M. luteus or B. megaterium PG or soluble E. coli PG and PGRP1 were both present. Statistic analysis suggested a synergistic effect caused by interaction between PGRP1 and these PGs. Taken together, these results indicated that PGRP1 is a member of the M. sexta prophenoloxidase activation system, which recognizes peptidoglycans from certain bacteria and initiates the host defense response. The unexplained difference between the purified PGs and intact bacteria clearly reflects our general lack of understanding of PGRP1-mediated recognition and how it leads to proPO activation. PMID:20416376

  1. Timely Activation of Budding Yeast APCCdh1 Involves Degradation of Its Inhibitor, Acm1, by an Unconventional Proteolytic Mechanism

    PubMed Central

    Melesse, Michael; Choi, Eunyoung; Hall, Hana; Walsh, Michael J.; Geer, M. Ariel; Hall, Mark C.

    2014-01-01

    Regulated proteolysis mediated by the ubiquitin proteasome system is a fundamental and essential feature of the eukaryotic cell division cycle. Most proteins with cell cycle-regulated stability are targeted for degradation by one of two related ubiquitin ligases, the Skp1-cullin-F box protein (SCF) complex or the anaphase-promoting complex (APC). Here we describe an unconventional cell cycle-regulated proteolytic mechanism that acts on the Acm1 protein, an inhibitor of the APC activator Cdh1 in budding yeast. Although Acm1 can be recognized as a substrate by the Cdc20-activated APC (APCCdc20) in anaphase, APCCdc20 is neither necessary nor sufficient for complete Acm1 degradation at the end of mitosis. An APC-independent, but 26S proteasome-dependent, mechanism is sufficient for complete Acm1 clearance from late mitotic and G1 cells. Surprisingly, this mechanism appears distinct from the canonical ubiquitin targeting pathway, exhibiting several features of ubiquitin-independent proteasomal degradation. For example, Acm1 degradation in G1 requires neither lysine residues in Acm1 nor assembly of polyubiquitin chains. Acm1 was stabilized though by conditional inactivation of the ubiquitin activating enzyme Uba1, implying some requirement for the ubiquitin pathway, either direct or indirect. We identified an amino terminal predicted disordered region in Acm1 that contributes to its proteolysis in G1. Although ubiquitin-independent proteasome substrates have been described, Acm1 appears unique in that its sensitivity to this mechanism is strictly cell cycle-regulated via cyclin-dependent kinase (Cdk) phosphorylation. As a result, Acm1 expression is limited to the cell cycle window in which Cdk is active. We provide evidence that failure to eliminate Acm1 impairs activation of APCCdh1 at mitotic exit, justifying its strict regulation by cell cycle-dependent transcription and proteolytic mechanisms. Importantly, our results reveal that strict cell-cycle expression profiles can be established independent of proteolysis mediated by the APC and SCF enzymes. PMID:25072887

  2. HMG-CoA reductase inhibitor rosuvastatin improves abnormal brain electrical activity via mechanisms involving eNOS.

    PubMed

    Seker, F B; Kilic, U; Caglayan, B; Ethemoglu, M S; Caglayan, A B; Ekimci, N; Demirci, S; Dogan, A; Oztezcan, S; Sahin, F; Yilmaz, B; Kilic, E

    2015-01-22

    Apart from its repressing effect on plasma lipid levels, 3-hydroxy-3-methyl glutaryl coenzyme A (HMG-CoA) reductase inhibitors exert neuroprotective functions in animal models of neurodegenerative disorders. In view of these promising observations, we were interested in whether HMG-CoA reductase inhibition would affect epileptiform activity in the brain. To elucidate this issue, atorvastatin, simvastatin and rosuvastatin were administered orally at a dose of 20 mg/kg each for 3 days and their anti-epileptic activities were tested and compared in rats. Epileptiform activity in the brain was induced by an intracortical penicillin G injection. Among HMG-CoA reductase inhibitors, simvastatin-treatment was less effective in terms of spike frequency as compared with atorvastatin- and rosuvastatin-treated animals. Atorvastatin treatment reduced spike frequencies and amplitudes significantly throughout the experiment. However, the most pronounced anti-epileptic effect was observed in rosuvastatin-treated animals, which was associated with improved blood-brain barrier (BBB) integrity, increased expression of endothelial nitric oxide synthase (eNOS) mRNA and decreased expressions of pro-apoptotic p53, Bax and caspase-3 mRNAs. Inhibition of eNOS activity with L-NG-Nitroarginine Methyl Ester (L-NAME) reversed the anti-epileptic effect of rosuvastatin significantly. However, L-NAME did not alter the effect of rosuvastatin on the levels of p53, Bax and caspase-3 mRNA expression. Here, we provide evidence that among HMG-CoA reductase inhibitors, rosuvastatin was the most effective statin on the reduction of epileptiform activity, which was associated with improved BBB permeability, increased expression of eNOS and decreased expressions of pro-apoptotic p53, Bax and caspase-3. Our observation also revealed that the anti-epileptic effect of rosuvastatin was dependent on the increased expression level of eNOS. The robust anti-epileptic effect encourages proof-of-concept studies with rosuvastatin in human epilepsy patients with hypercholesterolemia. PMID:25453767

  3. STAT1 pathway is involved in activation of caprine arthritis-encephalitis virus long terminal repeat in monocytes.

    PubMed

    Sepp, T; Tong-Starksen, S E

    1997-01-01

    The caprine arthritis-encephalitis virus (CAEV) long terminal repeat (LTR) is activated by gamma interferon (IFN-gamma) in promonocytic cells. We have previously shown that a 70-bp element is necessary and sufficient for the response of the CAEV LTR to this cytokine. At the 5' end, this 70-bp IFN-gamma response element contains sequence similarity to the gamma activated site (GAS). Here we demonstrate that the putative GAS element in the CAEV LTR binds specifically to a cellular factor induced by IFN-gamma in promonocytic cells. Substitution mutations in this consensus sequence eliminate binding of the inducible factor. The GAS element from the 70-bp motif is sufficient to confer responsiveness to IFN-gamma using a heterologous minimal promoter. Consistent with the binding data, the same mutations in the GAS element eliminate responsiveness to IFN-gamma in the context of both a functional CAEV LTR and a heterologous promoter. The cellular factor that binds to the GAS element is present from 5 min to 14 h after stimulation with IFN-gamma. Binding of the nuclear factor to the GAS element in the CAEV LTR is inhibited by antibody directed against STAT1 (p91/84). Thus, the GAS sequence in the CAEV LTR is essential for the response to IFN-gamma and a STAT1-like factor binds to this site. The STAT-1 signaling pathway provides at least one mechanism for activation of the CAEV LTR by IFN-gamma in monocytes. These data are the first demonstration of a role for a STAT family member in the regulation of a viral promoter. PMID:8985415

  4. Membrane potential regulates mitochondrial ATP-diphosphohydrolase activity but is not involved in progesterone biosynthesis in human syncytiotrophoblast cells.

    PubMed

    Flores-Herrera, Oscar; Olvera-Sánchez, Sofia; Esparza-Perusquía, Mercedes; Pardo, Juan Pablo; Rendón, Juan Luis; Mendoza-Hernández, Guillermo; Martínez, Federico

    2015-02-01

    ATP-diphosphohydrolase is associated with human syncytiotrophoblast mitochondria. The activity of this enzyme is implicated in the stimulation of oxygen uptake and progesterone synthesis. We reported previously that: (1) the detergent-solubilized ATP-diphosphohydrolase has low substrate specificity, and (2) purine and pyrimidine nucleosides, tri- or diphosphates, are fully dephosphorylated in the presence of calcium or magnesium (Flores-Herrera 1999, 2002). In this study we show that ATP-diphosphohydrolase hydrolyzes first the nucleoside triphosphate to nucleoside diphosphate, and then to nucleotide monophosphate, in the case of all tested nucleotides. The activation energies (Ea) for ATP, GTP, UTP, and CTP were 6.06, 4.10, 6.25, and 5.26kcal/mol, respectively; for ADP, GDP, UDP, and CDP, they were 4.67, 5.42, 5.43, and 6.22kcal/mol, respectively. The corresponding Arrhenius plots indicated a single rate-limiting step for each hydrolyzed nucleoside, either tri- or diphosphate. In intact mitochondria, the ADP produced by ATP-diphosphohydrolase activity depolarized the membrane potential (??m) and stimulated oxygen uptake. Mitochondrial respiration showed the state-3/state-4 transition when ATP was added, suggesting that ATP-diphosphohydrolase and the F1F0-ATP synthase work in conjunction to avoid a futile cycle. Substrate selectivity of the ATP-diphosphohydrolase was modified by ??m (i.e. ATP was preferred over GTP when the inner mitochondrial membrane was energized). In contrast, dissipation of ??m by CCCP produced a loss of substrate specificity and so the ATP-diphosphohydrolase was able to hydrolyze ATP and GTP at the same rate. In intact mitochondria, ATP hydrolysis increased progesterone synthesis as compared with GTP. Although dissipation of ??m by CCCP decreased progesterone synthesis, NADPH production restores steroidogenesis. Overall, our results suggest a novel physiological role for ??m in steroidogenesis. PMID:25444704

  5. Gastroprotective activity of Annona muricata leaves against ethanol-induced gastric injury in rats via Hsp70/Bax involvement.

    PubMed

    Moghadamtousi, Soheil Zorofchian; Rouhollahi, Elham; Karimian, Hamed; Fadaeinasab, Mehran; Abdulla, Mahmood Ameen; Kadir, Habsah Abdul

    2014-01-01

    The popular fruit tree of Annona muricata L. (Annonaceae), known as soursop and graviola, is a widely distributed plant in Central and South America and tropical countries. Leaves of A. muricata have been reported to possess antioxidant and anti-inflammatory activities. In this study, the gastroprotective effects of ethyl acetate extract of A. muricata leaves (EEAM) were investigated against ethanol-induced gastric injury models in rats. The acute toxicity test of EEAM in rats, carried out in two doses of 1 g/kg and 2 g/kg, showed the safety of this plant, even at the highest dose of 2 g/kg. The antiulcer study in rats (five groups, n=6) was performed with two doses of EEAM (200 mg/kg and 400 mg/kg) and with omeprazole (20 mg/kg), as a standard antiulcer drug. Gross and histological features showed the antiulcerogenic characterizations of EEAM. There was significant suppression on the ulcer lesion index of rats pretreated with EEAM, which was comparable to the omeprazole effect in the omeprazole control group. Oral administration of EEAM to rats caused a significant increase in the level of nitric oxide and antioxidant activities, including catalase, glutathione, and superoxide dismutase associated with attenuation in gastric acidity, and compensatory effect on the loss of gastric wall mucus. In addition, pretreatment of rats with EEAM caused significant reduction in the level of malondialdehyde, as a marker for oxidative stress, associated with an increase in prostaglandin E2 activity. Immunohistochemical staining also demonstrated that EEAM induced the downregulation of Bax and upregulation of Hsp70 proteins after pretreatment. Collectively, the present results suggest that EEAM has a promising antiulcer potential, which could be attributed to its suppressive effect against oxidative damage and preservative effect toward gastric wall mucus. PMID:25378912

  6. The involvement of the release of nitric oxide in the pharmacological activity of the new furoxan derivative CHF 2363.

    PubMed Central

    Civelli, M.; Giossi, M.; Caruso, P.; Razzetti, R.; Bergamaschi, M.; Bongrani, S.; Gasco, A.

    1996-01-01

    1. The mechanism of action and the pharmacological effects of the new furoxan derivative, CHF 2363 (4-ethoxy-3-phenylsulphonylfuroxan), were investigated. 2. Pre-incubation of CHF 2363 with human platelet-rich plasma produced a concentration-dependent inhibition of the platelet aggregation induced by collagen, adenosine diphosphate (ADP) and platelet activating factor (PAF). The test compound was about 5 times more potent than sodium nitroprusside. 3-Isobutyl-1-methyl-xanthine (IBMX) potentiated the antiaggregating effect of CHF 2363. 3. CHF 2363 was a potent inhibitor of rubbed endothelium rabbit aortic ring contraction induced by noradrenaline. Comparison of IC50 values showed that CHF 2363 was as potent as glyceryl trinitrate (GTN). 4. Increasing concentrations of CHF 2363 elevated platelet guanosine 3':5'-cyclic monophosphate (cyclic GMP) levels. Adenosine 3':5'-cyclic monophosphate (cyclic AMP) levels were unaffected. 5. Oxyhaemoglobin reduced all the pharmacological actions of the test compound. Moreover, CHF 2363 concentration-dependently released nitric oxide (NO) in platelet-rich plasma. The NO release was correlated to its ability to increase platelet cyclic GMP levels. 6. After exposure of rat aortic strips to supramaximal concentrations of GTN (550 microM), the vasorelaxant activity of CHF 2363 did not change, although that of GTN decreased about 55 fold. 7. It has been concluded that the new furoxan derivative CHF 2363 exerts a potent antiaggregating and vasorelaxant activity via NO release and increase of cyclic GMP levels. No in vitro cross tolerance between GTN and CHF 2363 was observed. PMID:8799563

  7. Gastroprotective activity of Annona muricata leaves against ethanol-induced gastric injury in rats via Hsp70/Bax involvement

    PubMed Central

    Moghadamtousi, Soheil Zorofchian; Rouhollahi, Elham; Karimian, Hamed; Fadaeinasab, Mehran; Abdulla, Mahmood Ameen; Kadir, Habsah Abdul

    2014-01-01

    The popular fruit tree of Annona muricata L. (Annonaceae), known as soursop and graviola, is a widely distributed plant in Central and South America and tropical countries. Leaves of A. muricata have been reported to possess antioxidant and anti-inflammatory activities. In this study, the gastroprotective effects of ethyl acetate extract of A. muricata leaves (EEAM) were investigated against ethanol-induced gastric injury models in rats. The acute toxicity test of EEAM in rats, carried out in two doses of 1 g/kg and 2 g/kg, showed the safety of this plant, even at the highest dose of 2 g/kg. The antiulcer study in rats (five groups, n=6) was performed with two doses of EEAM (200 mg/kg and 400 mg/kg) and with omeprazole (20 mg/kg), as a standard antiulcer drug. Gross and histological features showed the antiulcerogenic characterizations of EEAM. There was significant suppression on the ulcer lesion index of rats pretreated with EEAM, which was comparable to the omeprazole effect in the omeprazole control group. Oral administration of EEAM to rats caused a significant increase in the level of nitric oxide and antioxidant activities, including catalase, glutathione, and superoxide dismutase associated with attenuation in gastric acidity, and compensatory effect on the loss of gastric wall mucus. In addition, pretreatment of rats with EEAM caused significant reduction in the level of malondialdehyde, as a marker for oxidative stress, associated with an increase in prostaglandin E2 activity. Immunohistochemical staining also demonstrated that EEAM induced the downregulation of Bax and upregulation of Hsp70 proteins after pretreatment. Collectively, the present results suggest that EEAM has a promising antiulcer potential, which could be attributed to its suppressive effect against oxidative damage and preservative effect toward gastric wall mucus. PMID:25378912

  8. [Involvement of extracellular cAMP-specific phosphodiesterase in control of motile activity of Physarum polycephalum plasmodium].

    PubMed

    Matveeva, N B; Morozov, M A; Nezvetski?, A R; Orlova, T G; Teplov, V A; Be?lina, S I

    2010-01-01

    Possible involvement of extracellular cAMP-specific phosphodiesterase in the control of cell motile behavior has been investigated in Physarum polycephalum plasmodium, a multinuclear amoeboid cell with the autooscillatory mode of motility. It was found that the rate of the hydrolysis of 10 mM cAMP by a partially purified preparation of cAMP-specific phosphodiesterase secreted by the plasmodium in the course of migration decreases 20-30 times under the action of 1 mM dithiothreitol. In the presence of 1-5 mM of this strong reducing agent, the onset of the plasmodium spreading and the transition to the stage of migration were delayed in a concentration-dependent manner. In accordance with the morphological pattern of motile behavior, the duration of the maintenance of high frequency autooscillations, which normally precede the increase in the rate of the spreading and appear also in response to the application of attractants at spatially uniform concentrations, strongly increased by the action of dithiothreitol. The results obtained suggest that the autocrine production of cAMP and extracellular cAMP-specific phosphodiesterase is an important constituent of the mechanism controlling the motile behavior of the Physarum polycephalum plasmodium. PMID:21268353

  9. Aphid Feeding Activates Expression of a Transcriptome of Oxylipin-Based Defense Signals in Wheat Involved in Resistance to Herbivory

    PubMed Central

    SMITH, C. MICHAEL; LIU, XUMING; WANG, LIANG J.; LIU, XIANG; CHEN, MING-SHUN; STARKEY, SHARON; BAI, JIANFA

    2013-01-01

    Damage by the Russian wheat aphid (RWA), Diuraphis noxia, significantly reduces wheat and barley yields worldwide. In compatible interactions, virulent RWA populations flourish and susceptible plants suffer extensive leaf chlorophyll loss. In incompatible interactions, RWA reproduction and population growth are significantly reduced and RWA-related chlorophyll loss in resistant plants is minor. The objectives of this study were to develop an understanding of the molecular and phytochemical bases of RWA resistance in plants containing the Dnx resistance gene. Microarray, real-time polymerase chain reaction, and phytohormone assays were conducted to identify transcriptome components unique to RWA-infested Dnx plants and susceptible (Dn0) plants, and to identify and characterize putative genes involved in Dnx plant defense responses. We found that RWA-infested Dnx plants upregulated > 180 genes related to reactive oxygen species, signaling, pathogen defense, and arthropod allelochemical and physical defense. The expression of several of these genes in RWA-infested Dnx plants increased significantly from 6- to 24-h post infestation (hpi), but their expression in Dn0 plants, when present, was delayed until 48- to 96 hpi. Concentrations of 16- and 18-carbon fatty acids, trans-methyl-12-oxophytodienoic acid, and abscisic acid were significantly greater in Dnx foliage than in Dn0 foliage after RWA infestation, suggesting that Dnx RWA defense and resistance genes may be regulated via the oxylipin pathway. These findings provide a foundation for the elucidation of the molecular basis for compatible- and incompatible plant-aphid interactions. PMID:20229216

  10. Decolorizing activity of malachite green and its mechanisms involved in dye biodegradation by Achromobacter xylosoxidans MG1.

    PubMed

    Wang, Ji'ai; Qiao, Min; Wei, Kangbi; Ding, Junmei; Liu, Zhongzhong; Zhang, Ke-Qin; Huang, Xiaowei

    2011-01-01

    An Achromobacter xylosoxidans MG1 strainisolated from the effluent treatment plant of a textile and dyeing factory from Yunnan Province in China was found capable of decolorizing the malachite green dye at a high efficacy. Strain MG1 reduced 86% malachite green at the concentration of 2,000 mg/l within 1 h, representing a greater ability for decolorizing and a higher tolerance of this compound than all previously reported bacteria. Color removal was optimal at pH 6 and 38°C. Further experimental evidences demonstrated that both cytoplasmic and extracellular biodegradation contributed to the decolorization of malachite green. Nested PCR was employed to identify the candidate genes responsible for malachite green decolorization, and we identified a cytoplasmic triphenylmethane reductase gene with 100% amino acid similarity to the corresponding gene in Citrobacter sp. strain. In contrast to our expectation, the addition of metyrapone had little effect on the cytoplasmic biodegradation, suggesting that cytochrome P450 was not involved in the high-performance reduction. The extracellular biodegradation was likely attributable to the secretion of extracellular proteases and some heat-resistant compounds. PMID:21865764

  11. Protection conferred by Corticotropin-releasing hormone in rat primary cortical neurons against chemical ischemia involves opioid receptor activation.

    PubMed

    Charron, Charlaine; Schock, Sarah C; Proulx, Geneviève; Thompson, Charlie S; Hakim, Antoine M; Plamondon, Hélène

    2009-02-27

    Different studies have supported neuroprotective effects of Corticotropin-releasing hormone (CRH) against various excitotoxic and oxidative insults in vitro. However, the physiological mechanisms involved in this protection remain largely unknown. The present study was undertaken to determine the impact of CRH administration (at concentrations ranging from 200 fmol to 2 nmol) before and at delayed time intervals following potassium cyanide (KCN)-induced insult in rat primary cortical neurons. A second objective aimed to determine whether kappa and delta opioid receptor (KOR and DOR) blockade, using nor-binaltorphimine and naltrindole respectively (10 microM), could alter CRH-induced cellular protection. Our findings revealed that CRH treatments before or 3 and 8 h following KCN insult conferred significant protection against cortical injury, an effect blocked in cultures treated with alpha-helical CRH (9-41) prior to KCN administration. In addition, KOR and DOR blockade significantly reduced CRH-induced neuronal protection observed 3 but not 8 h post-KCN insult. Using western blotting, we demonstrated increased dynorphin, enkephalin, DOR and KOR protein expression in CRH-treated primary cortical neurons, and immunocytochemistry revealed the presence of opioid peptides and receptors in cortical neurons. These findings suggest protective effects of CRH against KCN-induced neuronal damage, and the contribution of the opioid system in modulating CRH actions. PMID:19146834

  12. Stimulation of hyaluronan biosynthesis by platelet-derived growth factor-BB and transforming growth factor-beta 1 involves activation of protein kinase C.

    PubMed Central

    Suzuki, M; Asplund, T; Yamashita, H; Heldin, C H; Heldin, P

    1995-01-01

    The intracellular signal transduction pathways that mediate the stimulatory effects of platelet-derived growth factor (PDGF)-BB and transforming growth factor (TGF)-beta on hyaluronan biosynthesis in human fibroblasts were investigated. The stimulatory effects of both PDGF-BB and TGF-beta 1 were dependent on protein kinase C (PKC), since the PKC inhibitor calphostin C inhibited the stimulation by the growth factors. Direct activation of PKC by phorbol 12-myristate 13-acetate (PMA) also stimulated hyaluronan production, and the combination of either PDGF-BB or TGF-beta 1 and PMA gave an increased effect. One possible mechanism for activation of PKC is via induction of phospholipase C (PLC) activity; U-17322, an inhibitor of PLC-gamma, was found to inhibit partially PDGF-BB-stimulated hyaluronan synthesis. PDGF-BB is known to activate PLC-gamma through tyrosine phosphorylation; however, a PDGF beta-receptor mutant unable to interact with and activate PLC-gamma was still able to mediate induction of hyaluronan biosynthesis, indicating that PDGF-mediated stimulation is not entirely dependent on PLC-gamma. The stimulations by PDGF-BB and TGF-beta 1 were partly dependent on protein synthesis, since parts of the effects were inhibited by cycloheximide; in contrast, the effects mediated by PMA were not. Our results indicate that PKC is involved in the transduction of the effects of growth factors on hyaluronan biosynthesis, and that the effects involve direct or indirect activation of existing hyaluronan synthetase molecules, as well as induction of new enzyme molecules. PMID:7741713

  13. Midazolam induces apoptosis in MA-10 mouse Leydig tumor cells through caspase activation and the involvement of MAPK signaling pathway

    PubMed Central

    So, Edmund Cheung; Lin, Yu-Xuan; Tseng, Chi Hao; Pan, Bo-Syong; Cheng, Ka-Shun; Wong, Kar-Lok; Hao, Lyh-Jyh; Wang, Yang-Kao; Huang, Bu-Miin

    2014-01-01

    Purpose The present study aims to investigate how midazolam, a sedative drug for clinical use with cytotoxicity on neuronal and peripheral tissues, induced apoptosis in MA-10 mouse Leydig tumor cells. Methods The apoptotic effect and underlying mechanism of midazolam to MA-10 cells were investigated by flow cytometry assay and Western blotting methods. Results Data showed that midazolam induced the accumulation of the MA-10 cell population in the sub-G1 phase and a reduction in the G2/M phase in a time- and dose-dependent manner, suggesting an apoptotic phenomenon. Midazolam could also induce the activation of caspase-8, -9, and -3 and poly (ADP-ribose) polymerase proteins. There were no changes in the levels of Bax and cytochrome-c, whereas Bid was significantly decreased after midazolam treatment. Moreover, midazolam decreased both pAkt and Akt expression. In addition, midazolam stimulated the phosphorylation of p38 and c-Jun NH2-terminal kinase but not extracellular signal-regulated kinase. Conclusion Midazolam could induce MA-10 cell apoptosis through the activation of caspase cascade, the inhibition of pAkt pathway, and the induction of p38 and c-Jun NH2-terminal kinase pathways. PMID:24611016

  14. Involvement of ?3-adrenergic receptor activation via cyclic GMP- but not NO-dependent mechanisms in human corpus cavernosum function

    PubMed Central

    Cirino, Giuseppe; Sorrentino, Raffaella; di Villa Bianca, Roberta d'Emmanuele; Popolo, Ada; Palmieri, Alessandro; Imbimbo, Ciro; Fusco, Ferdinando; Longo, Nicola; Tajana, Gianfranco; Ignarro, Louis J.; Mirone, Vincenzo

    2003-01-01

    The ?3-adrenoreceptor plays a major role in lipolysis but the role and distribution of ?3-receptors in other specific sites have not been extensively studied. ?3-adrenergic receptors are present not only in adipose tissue but also in human gall bladder, colon, prostate, and skeletal muscle. Recently, ?3-adrenergic receptor stimulation was shown to elicit vasorelaxation of rat aorta through the NO–cGMP signal transduction pathway. Here we show that ?3-receptors are present in human corpus cavernosum and are localized mainly in smooth muscle cells. After activation by a selective ?3-adrenergic receptor agonist, BRL 37344, there was a cGMP-dependent but NO-independent vasorelaxation that was selectively blocked by a specific ?3-receptor antagonist. In addition, we report that the human corpus cavernosum exhibits basal ?3-receptor-mediated vasorelaxant tone and that ?3-receptor activity is linked to inhibition of the RhoA/Rho-kinase pathway. These observations indicate that ?3-receptors may play a physiological role in mediating penile erection and, therefore, could represent a therapeutic target for treatment of erectile dysfunction. PMID:12707413

  15. Volatile Compounds in Honey: A Review on Their Involvement in Aroma, Botanical Origin Determination and Potential Biomedical Activities

    PubMed Central

    Manyi-Loh, Christy E.; Ndip, Roland N.; Clarke, Anna M.

    2011-01-01

    Volatile organic compounds (VOCs) in honey are obtained from diverse biosynthetic pathways and extracted by using various methods associated with varying degrees of selectivity and effectiveness. These compounds are grouped into chemical categories such as aldehyde, ketone, acid, alcohol, hydrocarbon, norisoprenoids, terpenes and benzene compounds and their derivatives, furan and pyran derivatives. They represent a fingerprint of a specific honey and therefore could be used to differentiate between monofloral honeys from different floral sources, thus providing valuable information concerning the honey’s botanical and geographical origin. However, only plant derived compounds and their metabolites (terpenes, norisoprenoids and benzene compounds and their derivatives) must be employed to discriminate among floral origins of honey. Notwithstanding, many authors have reported different floral markers for honey of the same floral origin, consequently sensory analysis, in conjunction with analysis of VOCs could help to clear this ambiguity. Furthermore, VOCs influence honey’s aroma described as sweet, citrus, floral, almond, rancid, etc. Clearly, the contribution of a volatile compound to honey aroma is determined by its odor activity value. Elucidation of the aroma compounds along with floral origins of a particular honey can help to standardize its quality and avoid fraudulent labeling of the product. Although only present in low concentrations, VOCS could contribute to biomedical activities of honey, especially the antioxidant effect due to their natural radical scavenging potential. PMID:22272147

  16. Fractalkine (CX3CL1) is involved in the early activation of hypothalamic inflammation in experimental obesity.

    PubMed

    Morari, Joseane; Anhe, Gabriel F; Nascimento, Lucas F; de Moura, Rodrigo F; Razolli, Daniela; Solon, Carina; Guadagnini, Dioze; Souza, Gabriela; Mattos, Alexandre H; Tobar, Natalia; Ramos, Celso D; Pascoal, Vinicius D; Saad, Mario J; Lopes-Cendes, Iscia; Moraes, Juliana C; Velloso, Licio A

    2014-11-01

    Hypothalamic inflammation is a common feature of experimental obesity. Dietary fats are important triggers of this process, inducing the activation of toll-like receptor-4 (TLR4) signaling and endoplasmic reticulum stress. Microglia cells, which are the cellular components of the innate immune system in the brain, are expected to play a role in the early activation of diet-induced hypothalamic inflammation. Here, we use bone marrow transplants to generate mice chimeras that express a functional TLR4 in the entire body except in bone marrow-derived cells or only in bone marrow-derived cells. We show that a functional TLR4 in bone marrow-derived cells is required for the complete expression of the diet-induced obese phenotype and for the perpetuation of inflammation in the hypothalamus. In an obesity-prone mouse strain, the chemokine CX3CL1 (fractalkine) is rapidly induced in the neurons of the hypothalamus after the introduction of a high-fat diet. The inhibition of hypothalamic fractalkine reduces diet-induced hypothalamic inflammation and the recruitment of bone marrow-derived monocytic cells to the hypothalamus; in addition, this inhibition reduces obesity and protects against diet-induced glucose intolerance. Thus, fractalkine is an important player in the early induction of diet-induced hypothalamic inflammation, and its inhibition impairs the induction of the obese and glucose intolerance phenotypes. PMID:24947351

  17. OsKinesin-13A Is an Active Microtubule Depolymerase Involved in Glume Length Regulation via Affecting Cell Elongation

    PubMed Central

    Deng, Zhu Yun; Liu, Ling Tong; Li, Tang; Yan, Song; Kuang, Bai Jian; Huang, Shan Jin; Yan, Chang Jie; Wang, Tai

    2015-01-01

    Grain size is an important trait influencing both the yield and quality of rice and its major determinant is glume size. However, how glume size is regulated remains largely unknown. Here, we report the characterization of OsKinesin-13A, which regulates cell elongation and glume length in rice. The mutant of OsKinesin-13A, sar1, displayed length reduction in grains and other organs including internodes, leaves and roots. The grain phenotype in sar1 was directly caused by reduction in glume length, which in turn restricted caryopsis size. Histological results revealed that length decrease in sar1 organs resulted from abnormalities in cell elongation. The orientation of cellulose microfibrils was defective in sar1. Consistently, sar1 showed reduced transverse orientation of cortical microtubules. Further observations demonstrated that microtubule turnover was decreased in sar1. OsKinesin-13A was shown to be an active microtubule depolymerase and mainly distributed on vesicles derived from the Golgi apparatus and destined for the cell surface. Thus, our results suggest that OsKinesin-13A utilizes its microtubule depolymerization activity to promote microtubule turnover, which may not only influence transverse orientation of cortical microtubules but also facilitate vesicle transport from the Golgi apparatus to the cell surface, and thus affects cellulose microfibril orientation and cell elongation. PMID:25807460

  18. Camalexin-Induced Apoptosis in Prostate Cancer Cells Involves Alterations of Expression and Activity of Lysosomal Protease Cathepsin D

    PubMed Central

    Smith, Basil; Randle, Diandra; Mezencev, Roman; Thomas, LeeShawn; Hinton, Cimona; Marah, Valerie

    2015-01-01

    Camalexin, the phytoalexin produced in the model plant Arabidopsis thaliana, possesses antiproliferative and cancer chemopreventive effects. We have demonstrated that the cytostatic/cytotoxic effects of camalexin on several prostate cancer (PCa) cells are due to oxidative stress. Lysosomes are vulnerable organelles to Reactive Oxygen Species (ROS)-induced injuries, with the potential to initiate and or facilitate apoptosis subsequent to release of proteases such as cathepsin D (CD) into the cytosol. We therefore hypothesized that camalexin reduces cell viability in PCa cells via alterations in expression and activity of CD. Cell viability was evaluated by MTS cell proliferation assay in LNCaP and ARCaP Epithelial (E) cells, and their respective aggressive sublines C4-2 and ARCaP Mesenchymal (M) cells, whereby the more aggressive PCa cells (C4-2 and ARCaPM) displayed greater sensitivity to camalexin treatments than the lesser aggressive cells (LNCaP and ARCaPE). Immunocytochemical analysis revealed CD relocalization from the lysosome to the cytosol subsequent to camalexin treatments, which was associated with increased protein expression of mature CD; p53, a transcriptional activator of CD; BAX, a downstream effector of CD, and cleaved PARP, a hallmark for apoptosis. Therefore, camalexin reduces cell viability via CD and may present as a novel therapeutic agent for treatment of metastatic prostate cancer cells. PMID:24699144

  19. Astringency is a trigeminal sensation that involves the activation of G protein-coupled signaling by phenolic compounds.

    PubMed

    Schöbel, Nicole; Radtke, Debbie; Kyereme, Jessica; Wollmann, Nadine; Cichy, Annika; Obst, Katja; Kallweit, Kerstin; Kletke, Olaf; Minovi, Amir; Dazert, Stefan; Wetzel, Christian H; Vogt-Eisele, Angela; Gisselmann, Günter; Ley, Jakob P; Bartoshuk, Linda M; Spehr, Jennifer; Hofmann, Thomas; Hatt, Hanns

    2014-07-01

    Astringency is an everyday sensory experience best described as a dry mouthfeel typically elicited by phenol-rich alimentary products like tea and wine. The neural correlates and cellular mechanisms of astringency perception are still not well understood. We explored taste and astringency perception in human subjects to study the contribution of the taste as well as of the trigeminal sensory system to astringency perception. Subjects with either a lesion or lidocaine anesthesia of the Chorda tympani taste nerve showed no impairment of astringency perception. Only anesthesia of both the lingual taste and trigeminal innervation by inferior alveolar nerve block led to a loss of astringency perception. In an in vitro model of trigeminal ganglion neurons of mice, we studied the cellular mechanisms of astringency perception. Primary mouse trigeminal ganglion neurons showed robust responses to 8 out of 19 monomeric phenolic astringent compounds and 8 polymeric red wine polyphenols in Ca(2+) imaging experiments. The activating substances shared one or several galloyl moieties, whereas substances lacking the moiety did not or only weakly stimulate responses. The responses depended on Ca(2+) influx and voltage-gated Ca(2+) channels, but not on transient receptor potential channels. Responses to the phenolic compound epigallocatechin gallate as well as to a polymeric red wine polyphenol were inhibited by the G?s inactivator suramin, the adenylate cyclase inhibitor SQ, and the cyclic nucleotide-gated channel inhibitor l-cis-diltiazem and displayed sensitivity to blockers of Ca(2+)-activated Cl(-) channels. PMID:24718416

  20. Involvement of tristetraprolin in transcriptional activation of hepatic 3-hydroxy-3-methylglutaryl coenzyme A reductase by insulin

    SciTech Connect

    Ness, Gene C., E-mail: gness@hsc.usf.edu [Department of Molecular Medicine, College of Medicine, University of South Florida, Tampa, FL 33612 (United States); Edelman, Jeffrey L.; Brooks, Patricia A. [Department of Molecular Medicine, College of Medicine, University of South Florida, Tampa, FL 33612 (United States)] [Department of Molecular Medicine, College of Medicine, University of South Florida, Tampa, FL 33612 (United States)

    2012-03-30

    Highlights: Black-Right-Pointing-Pointer siRNAs to tristetraprolin blocks transcription of HMGR in vivo in rat liver. Black-Right-Pointing-Pointer siRNAs to tristetraprolin inhibits insulin activation of HMGR transcription. Black-Right-Pointing-Pointer Insulin acts to rapidly increase tristetraprolin in liver nuclear extracts. -- Abstract: Several AU-rich RNA binding element (ARE) proteins were investigated for their possible effects on transcription of hepatic 3-hydroxy-3-methyglutaryl coenzyme A reductase (HMGR) in normal rats. Using in vivo electroporation, four different siRNAs to each ARE protein were introduced together with HMGR promoter (-325 to +20) luciferase construct and compared to saline controls. All four siRNAs to tristetraprolin (TTP) completely eliminated transcription from the HMGR promoter construct. Since insulin acts to rapidly increase hepatic HMGR transcription, the effect of TTP siRNA on induction by insulin was tested. The 3-fold stimulation by insulin was eliminated by this treatment. In comparison, siRNA to AU RNA binding protein/enoyl coenzyme A hydratase (AUH) had no effect. These findings indicate a role for TTP in the insulin-mediated activation of hepatic HMGR transcription.

  1. NK cell responses to cytomegalovirus infection lead to stable imprints in the human KIR repertoire and involve activating KIRs

    PubMed Central

    Liu, Lisa L.; Ivarsson, Martin A.; Sohlberg, Ebba; Björklund, Andreas T.; Retière, Christelle; Sverremark-Ekström, Eva; Traherne, James; Ljungman, Per; Schaffer, Marie; Price, David A.; Trowsdale, John; Michaëlsson, Jakob; Ljunggren, Hans-Gustaf

    2013-01-01

    Human natural killer (NK) cells are functionally regulated by killer cell immunoglobulin-like receptors (KIRs) and their interactions with HLA class I molecules. As KIR expression in a given NK cell is genetically hard-wired, we hypothesized that KIR repertoire perturbations reflect expansions of unique NK-cell subsets and may be used to trace adaptation of the NK-cell compartment to virus infections. By determining the human “KIR-ome” at a single-cell level in more than 200 donors, we were able to analyze the magnitude of NK cell adaptation to virus infections in healthy individuals. Strikingly, infection with human cytomegalovirus (CMV), but not with other common herpesviruses, induced expansion and differentiation of KIR-expressing NK cells, visible as stable imprints in the repertoire. Education by inhibitory KIRs promoted the clonal-like expansion of NK cells, causing a bias for self-specific inhibitory KIRs. Furthermore, our data revealed a unique contribution of activating KIRs (KIR2DS4, KIR2DS2, or KIR3DS1), in addition to NKG2C, in the expansion of human NK cells. These results provide new insight into the diversity of KIR repertoire and its adaptation to virus infection, suggesting a role for both activating and inhibitory KIRs in immunity to CMV infection. PMID:23325834

  2. The Involvement of NFAT Transcriptional Activity Suppression in SIRT1-Mediated Inhibition of COX-2 Expression Induced by PMA/Ionomycin

    PubMed Central

    Huang, Yue; Liu, Guang; Gao, Peng; Wan, Yan-Zhen; Zhang, Ran; Zhang, Zhu-Qin; Yang, Rui-Feng; Tang, Xiaoqiang; Xu, Jing; Wang, Xu; Chen, Hou-Zao; Liu, De-Pei

    2014-01-01

    SIRT1, a class III histone deacetylase, acts as a negative regulator for many transcription factors, and plays protective roles in inflammation and atherosclerosis. Transcription factor nuclear factor of activated T cells (NFAT) has been previously shown to play pro-inflammatory roles in endothelial cells. Inhibition of NFAT signaling may be an attractive target to regulate inflammation in atherosclerosis. However, whether NFAT transcriptional activity is suppressed by SIRT1 remains unknown. In this study, we found that SIRT1 suppressed NFAT-mediated transcriptional activity. SIRT1 interacted with NFAT, and the NHR and RHR domains of NFAT mediated the interaction with SIRT1. Moreover, we found that SIRT1 primarily deacetylated NFATc3. Adenoviral over-expression of SIRT1 suppressed PMA and calcium ionophore Ionomycin (PMA/Io)-induced COX-2 expression in human umbilical vein endothelial cells (HUVECs), while SIRT1 RNAi reversed the effects in HUVECs. Moreover, inhibition of COX-2 expression by SIRT1 in PMA/Io-treated HUVECs was largely abrogated by inhibiting NFAT activation. Furthermore, SIRT1 inhibited NFAT-induced COX-2 promoter activity, and reduced NFAT binding to the COX-2 promoter in PMA/Io-treated HUVECs. These results suggest that suppression of NFAT transcriptional activity is involved in SIRT1-mediated inhibition of COX-2 expression induced by PMA/Io, and that the negative regulatory mechanisms of NFAT by SIRT1 may contribute to its anti-inflammatory effects in atherosclerosis. PMID:24859347

  3. Involvement of the protein tyrosine phosphatase SHP-1 in Ras-mediated activation of the mitogen-activated protein kinase pathway.

    PubMed Central

    Krautwald, S; Büscher, D; Kummer, V; Buder, S; Baccarini, M

    1996-01-01

    Ubiquitously expressed SH2-containing tyrosine phosphatases interact physically with tyrosine kinase receptors or their substrates and relay positive mitogenic signals via the activation of the Ras-mitogen-activated protein kinase (MAPK) pathway. Conversely, the structurally related phosphatase SHP-1 is predominantly expressed in hemopoietic cells and becomes tyrosine phosphorylated upon colony-stimulating factor 1 treatment of macrophages without associating with the colony-stimulating factor 1 receptor tyrosine kinase. Mice lacking functional SHP-1 (me/me and me(v)/me(v)) develop systemic autoimmune disease with accumulation of macrophages, suggesting that SHP-1 may be a negative regulator of hemopoietic cell growth. By using macrophages expressing dominant negative Ras and the me(v)/me(v) mouse mutant, we show that SHP-1 is activated in the course of mitogenic signal transduction in a Ras-dependent manner and that its activity is necessary for the Ras-dependent activation of the MAPK pathway but not of the Raf-1 kinase. Consistent with a role for SHP-1 as an intermediate between Ras and the MEK-MAPK pathway, Ras-independent activation of the latter kinases by bacterial lipopolysaccharide occurred normally in me(v)/me(v) cells. Our results sharply accentuate the diversity of signal transduction in mammalian cells, in which the same signaling intermediates can be rearranged to form different pathways. PMID:8887625

  4. Mapping of Functional Domains of the Lipid Kinase Phosphatidylinositol 4-Kinase Type III Alpha Involved in Enzymatic Activity and Hepatitis C Virus Replication

    PubMed Central

    Harak, Christian; Radujkovic, Danijela; Taveneau, Cyntia; Reiss, Simon; Klein, Rahel; Bressanelli, Stéphane

    2014-01-01

    ABSTRACT The lipid kinase phosphatidylinositol 4-kinase III alpha (PI4KIII?) is an endoplasmic reticulum (ER)-resident enzyme that synthesizes phosphatidylinositol 4-phosphate (PI4P). PI4KIII? is an essential host factor for hepatitis C virus (HCV) replication. Interaction with HCV nonstructural protein 5A (NS5A) leads to kinase activation and accumulation of PI4P at intracellular membranes. In this study, we investigated the structural requirements of PI4KIII? in HCV replication and enzymatic activity. Therefore, we analyzed PI4KIII? mutants for subcellular localization, reconstitution of HCV replication in PI4KIII? knockdown cell lines, PI4P induction in HCV-positive cells, and lipid kinase activity in vitro. All mutants still interacted with NS5A and localized in a manner similar to that of the full-length enzyme, suggesting multiple regions of PI4KIII? are involved in NS5A interaction and subcellular localization. Interestingly, the N-terminal 1,152 amino acids were dispensable for HCV replication, PI4P induction, and enzymatic function, whereas further N-terminal or C-terminal deletions were deleterious, thereby defining the minimal PI4KIII? core enzyme at a size of ca. 108 kDa. Additional deletion of predicted functional motifs within the C-terminal half of PI4KIII? also were detrimental for enzymatic activity and for the ability of PI4KIII? to rescue HCV replication, with the exception of a proposed nuclear localization signal, suggesting that the entire C-terminal half of PI4KIII? is involved in the formation of a minimal enzymatic core. This view was supported by structural modeling of the PI4KIII? C terminus, suggesting a catalytic center formed by an N- and C-terminal lobe and an armadillo-fold motif, which is preceded by three distinct alpha-helical domains probably involved in regulation of enzymatic activity. IMPORTANCE The lipid kinase PI4KIII? is of central importance for cellular phosphatidylinositol metabolism and is a key host cell factor of hepatitis C virus replication. However, little is known so far about the structure of this 240-kDa protein and the functional importance of specific subdomains regarding lipid kinase activity and viral replication. This work focuses on the phenotypic analysis of distinct PI4KIII? mutants in different biochemical and cell-based assays and develops a structural model of the C-terminal enzymatic core. The results shed light on the structural and functional requirements of enzymatic activity and the determinants required for HCV replication. PMID:24920820

  5. Calmodulin activation of an endoplasmic reticulum-located calcium pump involves an interaction with the N-terminal autoinhibitory domain

    NASA Technical Reports Server (NTRS)

    Hwang, I.; Harper, J. F.; Liang, F.; Sze, H.

    2000-01-01

    To investigate how calmodulin regulates a unique subfamily of Ca(2+) pumps found in plants, we examined the kinetic properties of isoform ACA2 identified in Arabidopsis. A recombinant ACA2 was expressed in a yeast K616 mutant deficient in two endogenous Ca(2+) pumps. Orthovanadate-sensitive (45)Ca(2+) transport into vesicles isolated from transformants demonstrated that ACA2 is a Ca(2+) pump. Ca(2+) pumping by the full-length protein (ACA2-1) was 4- to 10-fold lower than that of the N-terminal truncated ACA2-2 (Delta2-80), indicating that the N-terminal domain normally acts to inhibit the pump. An inhibitory sequence (IC(50) = 4 microM) was localized to a region within valine-20 to leucine-44, because a peptide corresponding to this sequence lowered the V(max) and increased the K(m) for Ca(2+) of the constitutively active ACA2-2 to values comparable to the full-length pump. The peptide also blocked the activity (IC(50) = 7 microM) of a Ca(2+) pump (AtECA1) belonging to a second family of Ca(2+) pumps. This inhibitory sequence appears to overlap with a calmodulin-binding site in ACA2, previously mapped between aspartate-19 and arginine-36 (J.F. Harper, B. Hong, I. Hwang, H.Q. Guo, R. Stoddard, J.F. Huang, M.G. Palmgren, H. Sze inverted question mark1998 J Biol Chem 273: 1099-1106). These results support a model in which the pump is kept "unactivated" by an intramolecular interaction between an autoinhibitory sequence located between residues 20 and 44 and a site in the Ca(2+) pump core that is highly conserved between different Ca(2+) pump families. Results further support a model in which activation occurs as a result of Ca(2+)-induced binding of calmodulin to a site overlapping or immediately adjacent to the autoinhibitory sequence.

  6. Collagenolytic Activities of the Major Secreted Cathepsin L Peptidases Involved in the Virulence of the Helminth Pathogen, Fasciola hepatica

    PubMed Central

    Robinson, Mark W.; Corvo, Ileana; Jones, Peter M.; George, Anthony M.; Padula, Matthew P.; To, Joyce; Cancela, Martin; Rinaldi, Gabriel; Tort, Jose F.; Roche, Leda; Dalton, John P.

    2011-01-01

    Background The temporal expression and secretion of distinct members of a family of virulence-associated cathepsin L cysteine peptidases (FhCL) correlates with the entry and migration of the helminth pathogen Fasciola hepatica in the host. Thus, infective larvae traversing the gut wall secrete cathepsin L3 (FhCL3), liver migrating juvenile parasites secrete both FhCL1 and FhCL2 while the mature bile duct parasites, which are obligate blood feeders, secrete predominantly FhCL1 but also FhCL2. Methodology/Principal Findings Here we show that FhCL1, FhCL2 and FhCL3 exhibit differences in their kinetic parameters towards a range of peptide substrates. Uniquely, FhCL2 and FhCL3 readily cleave substrates with Pro in the P2 position and peptide substrates mimicking the repeating Gly-Pro-Xaa motifs that occur within the primary sequence of collagen. FhCL1, FhCL2 and FhCL3 hydrolysed native type I and II collagen at neutral pH but while FhCL1 cleaved only non-collagenous (NC, non-Gly-X-Y) domains FhCL2 and FhCL3 exhibited collagenase activity by cleaving at multiple sites within the ?1 and ?2 triple helix regions (Col domains). Molecular simulations created for FhCL1, FhCL2 and FhCL3 complexed to various seven-residue peptides supports the idea that Trp67 and Tyr67 in the S2 subsite of the active sites of FhCL3 and FhCL2, respectively, are critical to conferring the unique collagenase-like activity to these enzymes by accommodating either Gly or Pro residues at P2 in the substrate. The data also suggests that FhCL3 accommodates hydroxyproline (Hyp)-Gly at P3-P2 better than FhCL2 explaining the observed greater ability of FhCL3 to digest type I and II collagens compared to FhCL2 and why these enzymes cleave at different positions within the Col domains. Conclusions/Significance These studies further our understanding of how this helminth parasite regulates peptidase expression to ensure infection, migration and establishment in host tissues. PMID:21483711

  7. Wnt activity guides facial branchiomotor neuron migration, and involves the PCP pathway and JNK and ROCK kinases

    PubMed Central

    Vivancos, Valérie; Chen, Ping; Spassky, Nathalie; Qian, Dong; Dabdoub, Alain; Kelley, Matthew; Studer, Michèle; Guthrie, Sarah

    2009-01-01

    Background Wnt proteins play roles in many biological processes, including axon guidance and cell migration. In the mammalian hindbrain, facial branchiomotor (FBM) neurons undergo a striking rostral to caudal migration, yet little is known of the underlying molecular mechanisms. In this study, we investigated a possible role of Wnts and the planar cell polarity (PCP) pathway in this process. Results Here we demonstrate a novel role for Wnt proteins in guiding FBM neurons during their rostral to caudal migration in the hindbrain. We found that Wnt5a is expressed in a caudalhigh to rostrallow gradient in the hindbrain. Wnt-coated beads chemoattracted FBM neurons to ectopic positions in an explant migration assay. The rostrocaudal FBM migration was moderately perturbed in Wnt5a mutant embryos and severely disrupted in Frizzled3 mutant mouse embryos, and was aberrant following inhibition of Wnt function by secreted Frizzled-related proteins. We also show the involvement of the Wnt/PCP pathway in mammalian FBM neuron migration. Thus, mutations in two PCP genes, Vangl2 and Scribble, caused severe defects in FBM migration. Inhibition of JNK and ROCK kinases strongly and specifically reduced the FBM migration, as well as blocked the chemoattractant effects of ectopic Wnt proteins. Conclusion These results provide in vivo evidence that Wnts chemoattract mammalian FBM neurons and that Wnt5a is a candidate to mediate this process. Molecules of the PCP pathway and the JNK and ROCK kinases also play a role in the FBM migration and are likely mediators of Wnt signalling. PMID:19210786

  8. Involvement of nitric oxide (NO) signalling pathway in the antidepressant activity of essential oil of Valeriana wallichii Patchouli alcohol chemotype.

    PubMed

    Sah, Sangeeta Pilkhwal; Mathela, Chandra Shekhar; Chopra, Kanwaljit

    2011-11-15

    Valeriana wallichii DC (Valerianaceae), popularly named as Indian valerian has been shown to exist as three chemotypes. The present study evaluated the antidepressant like effect of root essential oil of Valeriana wallichii patchouli alcohol chemotype in both acute and chronic treatment study using forced swim test (FST). Mice (n=6 per group) received 10, 20 and 40 mg/kg p.o. doses of test drug. Single administration of oil significantly inhibited the immobility period (57.6% and 46.9%) at doses 20 and 40 mg/kg respectively without changing the motor function (p<0.05). Similarly, daily administration of essential oil (20mg/kg) for 14 days significantly reduced the immobility period (69.9%) in FST (p<0.05). The neurotransmitter levels in mouse brain were estimated on day 14 after the behavioral study. Significant increase in the level of norepinephrine (29%) and serotonin (19%) (p<0.05) was found at 20mg/kg dose, while no change was observed at 10 and 40 mg/kg doses. The antidepressant-like effect of essential oil (20mg/kg) was prevented by pretreatment of mice with l-arginine (750 mg/kg i.p.) and sildenafil (5mg/kg i.p). On the contrary, pretreatment of mice with l-NAME (10mg/kg i.p.) or methylene blue (10mg/kg i.p.) potentiated the antidepressant action of essential oil (10mg/kg). Taken together, these findings demonstrated that nitric oxide pathway is involved in mediating antidepressant like effect of essential oil from this chemotype. PMID:21795033

  9. A Xanthomonas campestris pv. campestris protein similar to catabolite activation factor is involved in regulation of phytopathogenicity.

    PubMed

    de Crecy-Lagard, V; Glaser, P; Lejeune, P; Sismeiro, O; Barber, C E; Daniels, M J; Danchin, A

    1990-10-01

    A DNA fragment from Xanthomonas campestris pv. campestris that partially restored the carbohydrate fermentation pattern of a cya crp Escherichia coli strain was cloned and expressed in E. coli. The nucleotide sequence of this fragment revealed the presence of a 700-base-pair open reading frame that coded for a protein highly similar to the catabolite activation factor (CAP) of E. coli (accordingly named CLP for CAP-like protein). An X. campestris pv. campestris clp mutant was constructed by reverse genetics. This strain was not affected in the utilization of various carbon sources but had strongly reduced pathogenicity. Production of xanthan gum, pigment, and extracellular enzymes was either increased or decreased, suggesting that CLP plays a role in the regulation of phytopathogenicity. PMID:2170330

  10. Hyperoxia-induced neonatal rat lung injury involves activation of TGF-? and Wnt signaling and is protected by rosiglitazone

    PubMed Central

    Dasgupta, Chiranjib; Sakurai, Reiko; Wang, Ying; Guo, Pinzheng; Ambalavanan, Namasivayam; Torday, John S.; Rehan, Virender K.

    2009-01-01

    Despite tremendous technological and therapeutic advances, bronchopulmonary dysplasia (BPD) remains a leading cause of respiratory morbidity in very low birth weight infants, and there are no effective preventive and/or therapeutic options. We have previously reported that hyperoxia-induced neonatal rat lung injury might be prevented by rosiglitazone (RGZ). Here, we characterize 1) perturbations in wingless/Int (Wnt) and transforming growth factor (TGF)-? signaling, and 2) structural aberrations in lung morphology following 7-day continuous in vivo hyperoxia exposure to neonatal rats. We also tested whether treatment of neonatal pups with RGZ, concomitant to hyperoxia, could prevent such aberrations. Our study revealed that hyperoxia caused significant upregulation of Wnt signaling protein markers lymphoid enhancer factor 1 (Lef-1) and ?-catenin and TGF-? pathway transducers phosphorylated Smad3 and Smad7 proteins in whole rat lung extracts. These changes were also accompanied by upregulation of myogenic marker proteins ?-smooth muscle actin (?-SMA) and calponin but significant downregulation of the lipogenic marker peroxisome proliferator-activated receptor-? (PPAR?) expression. These molecular perturbations were associated with reduction in alveolar septal thickness, radial alveolar count, and larger alveoli in the hyperoxia-exposed lung. These hyperoxia-induced molecular and morphological changes were prevented by systemic administration of RGZ, with lung sections appearing near normal. This is the first evidence that in vivo hyperoxia induces activation of both Wnt and TGF-? signal transduction pathways in lung and of its near complete prevention by RGZ. Hyperoxia-induced arrest in alveolar development, a hallmark of BPD, along with these molecular changes strongly implicates these proteins in hyperoxia-induced lung injury. Administration of PPAR? agonists may thus be a potential strategy to attenuate hyperoxia-induced lung injury and subsequent BPD. PMID:19304912

  11. Neuroprotective Effect of 6-Paradol in Focal Cerebral Ischemia Involves the Attenuation of Neuroinflammatory Responses in Activated Microglia

    PubMed Central

    Park, Sung Hyuk; Chun, Kwang-Hoon; Kim, Sun Yeou; Shin, Dong Yun; Choi, Ji Woong

    2015-01-01

    Paradols are non-pungent and biotransformed metabolites of shogaols and reduce inflammatory responses as well as oxidative stress as shogaols. Recently, shogaol has been noted to possess therapeutic potential against several central nervous system (CNS) disorders, including cerebral ischemia, by reducing neuroinflammation in microglia. Therefore, paradol could be used to improve neuroinflammation-associated CNS disorders. Here, we synthesized paradol derivatives (2- to 10-paradols). Through the initial screening for anti-inflammatory activities using lipopolysaccharide (LPS)-stimulated BV2 microglia, 6-paradol was chosen to be the most effective compound without cytotoxicity. Pretreatment with 6-paradol reduced neuroinflammatory responses in LPS-stimulated BV2 microglia by a concentration-dependent manner, which includes reduced NO production by inhibiting iNOS upregulation and lowered secretion of proinflammatory cytokines (IL-6 and TNF-?). To pursue whether the beneficial in vitro effects of 6-paradol leads towards in vivo therapeutic effects on transient focal cerebral ischemia characterized by neuroinflammation, we employed middle cerebral artery occlusion (MCAO)/reperfusion (M/R). Administration of 6-paradol immediately after reperfusion significantly reduced brain damage in M/R-challenged mice as assessed by brain infarction, neurological deficit, and neural cell survival and death. Furthermore, as observed in cultured microglia, 6-paradol administration markedly reduced neuroinflammation in M/R-challenged brains by attenuating microglial activation and reducing the number of cells expressing iNOS and TNF-?, both of which are known to be produced in microglia following M/R challenge. Collectively, this study provides evidences that 6-paradol effectively protects brain after cerebral ischemia, likely by attenuating neuroinflammation in microglia, suggesting it as a potential therapeutic agent to treat cerebral ischemia. PMID:25789481

  12. The two N-glycans present on bovine Pofut1 are differently involved in its solubility and activity.

    PubMed

    Loriol, Céline; Audfray, Aymeric; Dupuy, Fabrice; Germot, Agnès; Maftah, Abderrahman

    2007-03-01

    O-Fucosylation is a post-translational glycosylation in which an O-fucose is covalently attached to the hydroxyl group of a specific serine or threonine residue. This modification occurs within the consensus sequence C2X(4-5)(S/T)C3 present on epidermal growth factor-like repeats of several proteins, including the Notch receptors and their ligands. The enzyme responsible for the addition of O-fucose to epidermal growth factor-like repeats is protein O-fucosyltransferase 1. Protein O-fucosyltransferase 1-mediated O-fucosylation is essential in Notch signaling, folding and targeting to the cell surface. Here, we studied the expression pattern of protein O-fucosyltransferase 1 in cattle and showed that the active enzyme is present in all tissues examined from embryo and adult as a glycoprotein with two N-glycans. By comparing protein O-fucosyltransferase 1 sequences available in databases, we observed that mammalian protein O-fucosyltransferase 1 enzymes possess two putative N-glycosylation sites, and that only the first is conserved among bilaterians. To gain more insight regarding the significance of N-glycans on protein O-fucosyltransferase 1, we substituted, by site-directed mutagenesis, bovine protein O-fucosyltransferase 1 N65, N163 or both, with L or Q. We demonstrated that the loss of N-glycan on N163 caused a slight decrease in protein O-fucosyltransferase 1 activity. In contrast, glycosylation of N65 was crucial for protein O-fucosyltransferase 1 functionality. Loss of glycosylation at N65 resulted in aggregation of protein O-fucosyltransferase 1, suggesting that N-glycosylation at this site is essential for proper folding of the enzyme. PMID:17263732

  13. P2X7R is involved in the progression of atherosclerosis by promoting NLRP3 inflammasome activation

    PubMed Central

    PENG, KUANG; LIU, LUSHAN; WEI, DANGHENG; LV, YUNCHENG; WANG, GANG; XIONG, WENHAO; WANG, XIAOQING; ALTAF, AFRASYAB; WANG, LILI; HE, DAN; WANG, HONGYAN; QU, PENG

    2015-01-01

    Purinergic 2X7 receptor (P2X7R) and nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) are expressed in macrophages in atherosclerotic lesions. However, the mechanisms through which P2X7R participates in the inflammatory response in atherosclerosis remain largely unknown. The aim of the present study was to investigate the role of P2X7R in atherosclerosis and the mechanisms of action of the NLRP3 inflammasome following stimulation with oxidized low-density lipoprotein (oxLDL). We observed the expression and distribution of P2X7R in the atherosclerotic plaque in the coronary arteries from an autopsy specimen and in that of the aortic sinuses of apoE?/? mice by immunohistochemistry and immunofluorescence staining. The specificity of short interfering RNA (siRNA) was used to suppress P2X7R and NLRP3 m