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MacDonald KS, Haq K, Chan J, Iwajomo O, Janes M, Perciani C, Pilon R, Caldwell D, Sandstrom P, Willer DO. O01.6 Persistent SIV-Seronegative Macaque Monkeys Generate Multi-Cytokine Anti- SIV Mucosal Immune Responses Following Serial Low-Dose SIV Mucosal Challenge. Br J Vener Dis 2013. [DOI: 10.1136/sextrans-2013-051184.0088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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2
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Parfett C, Macmillan J, Pilon R. Oxidative stress mediates tumor promoter-induced proliferin gene-expression in c3h10t1/2 cells. Int J Oncol 2012; 3:917-25. [PMID: 21573453 DOI: 10.3892/ijo.3.5.917] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Increased expression of the proliferin gene family occurs upon exposure of C3H10T1/2 cells to a broad range of chemical agents known to promote morphological transformation and likely to increase cellular reactive oxygen species. To determine if proliferin gene expression is influenced by reactive oxygen species, superoxide radicals were generated in culture by the xanthine/xanthine oxidase couple. The 1 kb cytoplasmic proliferin transcript accumulated up to ten-fold following extracellular superoxide production. Within certain concentration ranges of catalase and superoxide dismutase activity, xanthine oxidase-induced proliferin expression was reduced to control levels, while expression was increased at other concentrations. Induction of proliferin by the tumour promoters butylated hydroxytoluene or TPA was efficiently inhibited at certain concentrations of catalase and superoxide dismutase, but retinoic acid had no effect. Proliferin induction by a recently identified promoter of transformation, tri-n-butyltin chloride, was stimulated by catalase, superoxide dismutase and retinoic acid, but inhibited at higher concentrations of N-acetyl cysteine. c-fos preceded proliferin induction by butylated hydroxytoluene, but several other oncogenes and growth-regulated genes were unaffected. The results support a mechanism for tumour promoter-induced proliferin gene expression that involves a response to superoxide anions, hydrogen peroxide or other shifts in the cellular equilibrium between pro-oxidant and anti-oxidant moieties.
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Luo M, Tang D, Capina R, Yuan X, Prego C, Pinto JC, Alonso M, Barry C, Pilon R, Daniuk C, Tuff J, Pillet S, La D, Bielawny T, Czarnecki C, Lacap P, Peters H, Wong G, Kimani M, Wachihi C, Kimani J, Ball TB, Sandstrom P, Kobinger G, Plummer FA. A novel HIV vaccine targets the 12 protease cleavage sites. Retrovirology 2012. [PMCID: PMC3441448 DOI: 10.1186/1742-4690-9-s2-p304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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4
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Orysiuk D, Lawrence J, Prashar T, Spangelo L, Pilon R, Fournier J, Rud E, Sandstrom P, Plummer FA, Luo M. Evidence of recombination producing allelic diversity in MHC class I Mafa-B and -A alleles in cynomolgus macaques. ACTA ACUST UNITED AC 2012; 79:351-8. [PMID: 22489944 DOI: 10.1111/j.1399-0039.2012.01867.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The MHC class I-A and -B genes of cynomolgus macaques are highly polymorphic. These genes encode proteins presenting peptides to CD8+ T cells to initiate adaptive immune response. Recombination events are one way the diversity of these alleles can be increased. Such events have been well characterized in humans, but have not been as well characterized in macaques. In order to identify and examine recombinations that create new alleles, it is important to analyze intron sequences. Intron sequences have been shown to be important to understand the evolutionary mechanisms involved in the generation of major histocompatibility complex (MHC) alleles and loci. Thus far, there have been relatively few intron sequences reported for MHC class I alleles in macaques, and this has hampered the understanding of MHC organization and evolution in macaques. In this study, we present evidence of a gene conversion event generating the Mafa-B*099 allele lineage by the combination of Mafa-B*054 and Mafa-B*095 allele lineages. A potential recombination between the Mafa-A3*13 and Mafa-A4:14 lineages was also observed, but it is less clear due to lack of intron 2 sequence. This report stresses the role that recombination can play in MHC class I diversity in cynomologus macaques, and the importance of introns in identifying and analyzing such events.
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Affiliation(s)
- D Orysiuk
- Department of Medical Microbiology, University of Manitoba, Winnipeg, MB, Canada
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Lawrence J, Orysiuk D, Prashar T, Pilon R, Fournier J, Rud E, Sandstrom P, Plummer FA, Luo M. Identification of 23 novel MHC class I alleles in cynomolgus macaques of Philippine and Philippine/Mauritius origins. ACTA ACUST UNITED AC 2012; 79:306-7. [PMID: 22236321 DOI: 10.1111/j.1399-0039.2011.01829.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We report here novel Mafa-A, -AG and -B alleles identified in two groups of cynomolgus macaques.
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Affiliation(s)
- J Lawrence
- Department of Medical Microbiology, University of Manitoba, Winnipeg, MB, Canada
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6
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Ambagala A, Willer DO, Chan J, Marsh A, Sandstrom P, Pilon R, Fournier J, MacDonald KS. P19-07. Development of a protective HIV/SIV vaccine based on a self-boosting cytomegalovirus vector. Retrovirology 2009. [PMCID: PMC2767834 DOI: 10.1186/1742-4690-6-s3-p327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
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7
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Lorello G, la Porte C, Pilon R, Zhang G, Karnauchow T, MacPherson P. Discordance in HIV-1 viral loads and antiretroviral drug concentrations comparing semen and blood plasma. HIV Med 2009; 10:548-54. [PMID: 19515092 DOI: 10.1111/j.1468-1293.2009.00725.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVES For individuals not on antiretroviral therapy, the risk of heterosexual transmission of HIV appears negligible when blood plasma (BP) viral loads are <1500 HIV-1 RNA copies/mL. It is not clear whether this observation can be extrapolated to individuals on highly active antiretroviral therapy (HAART). Because of differential tissue penetration, antiretroviral drug concentrations may be sufficient to maintain an undetectable viral load in the BP yet not achieve adequate levels to suppress HIV in the genital tract. Therefore, we wanted to correlate HIV viral loads and drug concentrations in semen plasma (SP) and BP. METHODS Thirty-three men were included. All were on combination antiretroviral therapy with an undetectable BP viral load for at least 1 year. Blood and semen samples were collected within 2 h of each other and tested for HIV RNA by the NucliSens QT (bioMerieux, St Laurent, QC, Canada) method; drug concentrations were determined by liquid chromatography tandem mass spectrometry. RESULTS Two of the 33 patients (6.1%) with BP viral loads below detection had time-matched HIV viral loads in SP > or =700 copies/mL. Both patients were on efavirenz, the SP concentrations of which were < or =10% of the levels in BP and well below the minimal therapeutic drug monitoring target concentration required to suppress HIV. CONCLUSIONS Because, at least in part, of poor drug penetration into the genital tract, an undetectable HIV viral load in the BP does not guarantee an undetectable viral load in semen. In view of this, caution should be taken in concluding that patients on HAART with suppressed viraemia are sexually non-infectious.
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Affiliation(s)
- G Lorello
- Faculty of Medicine, University of Ottawa, Ottawa, Canada
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8
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Mandy F, Janossy G, Bergeron M, Pilon R, Faucher S. Affordable CD4 T-cell enumeration for resource-limited regions: A status report for 2008. Cytometry 2008; 74 Suppl 1:S27-39. [DOI: 10.1002/cyto.b.20414] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Grandlic CJ, Geib I, Pilon R, Sandrin TR. Lead pollution in a large, prairie-pothole lake (Rush Lake, WI, USA): effects on abundance and community structure of indigenous sediment bacteria. Environ Pollut 2006; 144:119-26. [PMID: 16513232 DOI: 10.1016/j.envpol.2005.12.029] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2005] [Revised: 12/21/2005] [Accepted: 12/27/2005] [Indexed: 05/06/2023]
Abstract
Rush Lake (WI, USA), the largest prairie-pothole lake east of the Mississippi River, has been contaminated with lead pollution as a result of over 140 years of waterfowl hunting. We examined: (1) the extent of lead pollution in Rush Lake sediments and (2) whether lead pollution in Rush Lake is affecting the abundance and community structure of indigenous sediment bacteria. Sediment lead concentrations did not exceed 59 mg Pb kg(-1) dry sediment. No relationship was observed between sediment lead concentration and the abundance of aerobic (P=0.498) or anaerobic (P=0.416) heterotrophic bacteria. Similarly, lead did not appear to affect bacterial community structure when considering both culturable and nonculturable community members. In contrast, the culturable fraction of sediment bacteria in samples containing 59 mg Pb kg(-1) exhibited a unique community structure. While factors other than lead content likely play roles in determining bacterial community structure in the sediments of Rush Lake, these data suggest that the culturable fraction of sediment bacterial communities is affected by elevated lead levels.
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Affiliation(s)
- Christopher J Grandlic
- Department of Biology and Microbiology, University of Wisconsin Oshkosh, 800 Algoma Blvd, 142 Halsey Science Center, Oshkosh, WI 54901, USA
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10
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Thistle P, Gottesman M, Pilon R, Glazier RH, Arbess G, Phillips E, Wald RL, Chitsike I, Simor A, Chipato T, Silverman M. A randomized control trial of an Ultra-Short zidovudine regimen in the prevention of perinatal HIV transmission in rural Zimbabwe. Cent Afr J Med 2004; 50:79-84. [PMID: 16411341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
OBJECTIVE To assess the practicality and effectiveness of an Ultra-Short zidovudine regimen for prevention of perinatal HIV transmission in rural Zimbabwe. DESIGN Double-blinded placebo-controlled randomized clinical trial. SETTING The Salvation Army Howard Hospital, a district hospital in rural Zimbabwe. SUBJECTS 222 HIV positive pregnant women presenting for antenatal care prior to 36 weeks were randomized. Twenty nine women were lost to follow up. INTERVENTION In the Thai regimen, mothers received zidovudine (300 mg po bid) from 36 weeks gestation until labour, and zidovudine (300 mg po q3h) during labour, and the neonates received a placebo. In the Ultra-Short regimen, the mothers received a placebo from 36 weeks to labour, then zidovudine (300 mg po q3h) in labour. The neonates received zidovudine (2 mg/kg po qid) for the first three days of life. MAIN OUTCOME MEASURE Infant HIV RNA status at six weeks of life. RESULTS Results were available for 90 infants from the Thai group and 89 infants from the Ultra-Short group. Infant HIV seroconversion rates at six weeks of life were 18.9% (95%CI 10.8 to 27.0) with the Thai regimen, and 15.7% [95% Confidence Interval (CI) 8.1 to 23.4] with the Ultra-Short regimen. The upper bound of seroconversion in the Ultra-Short group was lower than the 25% seroconversion boundary that was specified to show equivalence. CONCLUSIONS Although the Ultra-Short regimen has equivalent efficacy to the Thai regimen, it also has many practical advantages. Ultra-Short is thus a preferable protocol.
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Affiliation(s)
- P Thistle
- The Salvation Army Howard Hospital, Glendale, Zimbabwe
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11
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Parfett CL, Marquardt T, Pilon R. Promotion of morphological transformation by Di-n-butyltin dichloride in C3H/10T1/2 cells: prediction by prior expression of tumour promoter-responsive genes. Food Chem Toxicol 2000; 38:339-49. [PMID: 10722888 DOI: 10.1016/s0278-6915(99)00157-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Previous studies in our laboratory have shown that chemical treatments may induce increases in proliferin gene family mRNA accumulation in cultured murine embryonic cells. Proliferin inductions are highly correlated with subsequent promotional outcomes during two-stage focus-formation assays in C3H/10T1/2 cell cultures. In work reported here, the strong affiliation between these two responses was further validated after treating cells with di-n-butyltin dichloride which is a polyvinyl chloride (PVC) plastic additive that often contaminates food and water. Increased proliferin expression and promotion of morphological transformation occurred at similar concentrations. Promotion of transformation was detected at di-n-butyltin dichloride concentrations of 80 nM (24 ng/ml) and above, if added to initiated cultures before confluent monolayers had formed. Proliferin induction and morphological transformation were both reduced in confluent cultures treated with di-n-butyltin dichloride, as compared to subconfluent cultures. Proliferin expression measured in near-confluent cultures was induced up to 10-fold during the 36-hr period following di-n-butyltin dichloride exposure and was accompanied by increased accumulation of transcripts from many genes regulated by oxidative stresses, growth-inducing agents, and/or other promoting agents (asbestos, superoxide radicals ). Di-n-butyltin dichloride-induced mRNA species included members of the fos and jun proto-oncogene families, c-myc, egr1, ribonucleotide reductase (R2 subunit), odc, macrophage chemotactic protein/je, hsp70, metallothionine IIA, c-sod and mn-sod. The observed patterns of RNA accumulation suggested that a small subset of mRNA species, including proliferin, exhibit regulatory behaviour as a response to dissimilar agents or conditions that promote focus-formation in C3H/10T1/2 cultures. Plausible predictions of promotional effects in two-stage morphological transformation assays can be made from gene-expression responses to test agents.
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Affiliation(s)
- C L Parfett
- Mutagenesis Section, Environmental Health Directorate, Health Canada, Environmental Health Centre, Tunney's Pasture, Ottawa, Ontario, Canada.
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12
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Biggar RJ, Janes M, Pilon R, Miotti P, Taha TE, Broadhead R, Mtimivalye L, Kumwenda N, Cassol S. Virus levels in untreated African infants infected with human immunodeficiency virus type 1. J Infect Dis 1999; 180:1838-43. [PMID: 10558939 DOI: 10.1086/315122] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
In developed areas, human immunodeficiency virus (HIV)-infected infants have high virus levels and rapidly progress to death. HIV levels were assessed in 1994-1997 in untreated infants in Malawi by analysis of dried blood spots tested by nucleic acid silica-bound amplification. Of 24 umbilical cord blood (CB)-positive samples, 83% had >10,000 copies/mL. The median virus level was 78,000 copies/mL. First positive sample median levels were 355,000 copies/mL among 52 perinatally infected infants and 130,000 copies/mL among 43 infants infected by breast-feeding. Virus levels were stable, and initial levels predicted levels 1 year after infection (P=.005), at which time levels did not significantly differ among in utero, perinatally, or postnatally infected infants. Thus, neither age at infection nor route of infection significantly influenced HIV levels measured 1 year after infection. Most (87%) CB-positive infants were infected before labor onset, since virus levels greatly exceeded those expected in their mothers.
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Affiliation(s)
- R J Biggar
- Viral Epidemiology Branch, National Cancer Institute, National Institute of Allergy and Infectious Diseases, Rockville, MD 20862, USA.
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Cassol SA, Diaz-Mitoma F, Pilon R, Janes M, Cameron DW. Quantification of HIV-1 RNA in Dried Plasma Spots (DPS) : A Field Approach to Therapeutic Monitoring. Methods Mol Med 1999; 17:139-149. [PMID: 21380665 DOI: 10.1385/0-89603-369-4:139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The ability to accurately measure viral RNA in the plasma (1-3) and intracellular (4-7) compartments of HIV-1-infected persons has led to a dramatic improvement in the understanding of the natural history of HIV-1 and AIDS. A number of recent studies have convincingly demonstrated that high levels of viral replication occur at all stages of disease (8-10), and that changes in viral RNA load are predictive of disease outcome (11,12), and response to therapy (13,14). These findings, combined with the introduction of potent new antivirals (15,16), have stimulated a growing interest in viral load monitoring, both as a function of disease status, and as a predictor of disease progression and therapeutic efficacy.
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Affiliation(s)
- S A Cassol
- Ottawa General Hospital Research Institute, Ottawa, Ontario, Canada
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14
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Cassol S, Gill MJ, Pilon R, Cormier M, Voigt RF, Willoughby B, Forbes J. Quantification of human immunodeficiency virus type 1 RNA from dried plasma spots collected on filter paper. J Clin Microbiol 1997; 35:2795-801. [PMID: 9350736 PMCID: PMC230064 DOI: 10.1128/jcm.35.11.2795-2801.1997] [Citation(s) in RCA: 91] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
To assess dried plasma spots (DPSs) as a source of material for virus quantification, human immunodeficiency virus type 1 (HIV-1) RNA levels were quantified in matched DPS and liquid plasma samples from 73 infected patients, including 5 neonates and 4 adult patients with acute HIV-1 infection. Quantifications were performed by commercially available assays (NASBA [nucleic acid sequence-based amplification] or Amplicor, or both). There was a strong correlation between HIV-1 RNA levels in plasma and DPSs. More importantly, there was no decline in HIV-1 RNA levels in DPSs stored for as long as 2 weeks at 20 degrees C. Similarly, storage of DPSs for 3 days at 37 degrees C resulted in no decrease in viral RNA levels. For patients with primary infection, the DPS method allowed for the measurement of RNA levels in plasma during the initial spike in the level of viremia and in the subsequent period of suppressed viral replication. DPS quantification was equally informative in the neonatal setting, with all five newborns showing HIV-1 RNA loads of greater than 4.991 log10 copies/ml. We conclude that the viral RNA levels in DPSs are equivalent to those measured in fresh-frozen plasma. The ease and economy of DPS sampling, the minute volumes required, and the unexpected stability of dried RNA suggest that the use of DPSs will be particularly valuable for small-volume neonatal samples and large, population-based studies in which cold storage and transportation present special problems, as is often the case in developing countries. The ability to measure viral changes during primary infection suggests that the method will be useful for assessing vaccine efficacy in large field trials.
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Affiliation(s)
- S Cassol
- Ottawa General Hospital Research Institute and the University of Ottawa, Ontario, Canada
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15
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Parfett CL, Pilon R, Caldeira AA. Asbestos promotes morphological transformation and elevates expression of a gene family invariably induced by tumor promoters in C3H/10T1/2 cells. Carcinogenesis 1996; 17:2719-26. [PMID: 9006111 DOI: 10.1093/carcin/17.12.2719] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The murine proliferin gene family, which has been shown to respond consistently to tumor promoters and other cellular pro-oxidant agents in C3H/10T1/2 cells, was used to monitor responses after treatment of these cell cultures with toxic, pro-oxidant asbestos fibres. Proliferin mRNA levels were increased by amosite, crocidolite or chrysotile asbestos fibres, especially in the presence of fresh serum and at low cell densities. Promotion of morphological transformation was confirmed in two-stage focus formation assays using crocidolite at a fibre density that induced proliferin expression. Asbestos-induced gene expression was inhibited by millimolar levels of N-acetylcysteine (NAC), supporting a linkage between: (i) induced oxidant stress that was sufficient to promote morphological transformation; (ii) induction of proliferin expression. Other anti-oxidant compounds (dithiothreitol and pyrrolidine dithiocarbamate) or enzymes (superoxide dismutase and catalase) did not inhibit induced expression. Non-fibrous powders (titanium dioxide, quartz or silica gel) were also effective inducers of proliferin mRNA accumulation. Latex beads and activated charcoal were effective at higher particle densities, implying that ubiquitous particle-induced surface membrane effects can lead to an NAC-reversible step necessary for proliferin induction. The results showed that asbestos resembled all other promoters of morphological transformation in C3H/10T1/2 cells in that an antioxidant-sensitive induction of the proliferin gene family occurred following treatment.
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Affiliation(s)
- C L Parfett
- Environmental Health Directorate, Health Canada, Ottawa
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16
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Parfett CL, Pilon R. Oxidative stress-regulated gene expression and promotion of morphological transformation induced in C3H/10T1/2 cells by ammonium metavanadate. Food Chem Toxicol 1995; 33:301-8. [PMID: 7737603 DOI: 10.1016/0278-6915(94)00141-a] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Promoters of C3H/10T1/2 cell morphological transformation that elevate intracellular oxidant levels can be distinguished by a spectrum of induced gene expression, which includes the oxidant-responsive murine proliferin gene family. Proliferin transcripts were induced 40- to 100-fold by 20 microM ammonium metavanadate, 20-fold by 5 microM vanadium pentoxide but only three-fold by vanadium oxide sulfate. Consistent with its response to other oxidant chemicals, induction of proliferin by ammonium metavanadate was inhibited almost completely by the antioxidant N-acetylcysteine (8 mM). Ammonium metavanadate (5 microM), added as promoter in two-stage morphological transformation assays, amplified yields of Type II and Type III foci in monolayers of 20-methylcholanthrene-initiated C3H/10T1/2 cells. Ammonium metavanadate also induced formation of Type II foci in single-step transformation assays. The results suggest that pentavalent vanadium compounds could promote morphological transformation in C3H/10T1/2 cells by creating a cellular state of oxidative stress, sufficient to induce elevated expression of the proliferin gene family.
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MESH Headings
- Animals
- Antioxidants/pharmacology
- Autoradiography
- Blotting, Northern
- Cell Line
- Cell Transformation, Neoplastic/drug effects
- Cell Transformation, Neoplastic/genetics
- DNA Damage/drug effects
- DNA Damage/genetics
- DNA, Complementary/genetics
- DNA, Complementary/metabolism
- Densitometry
- Gene Expression Regulation, Neoplastic/drug effects
- Gene Expression Regulation, Neoplastic/genetics
- Glycoproteins/genetics
- Growth Substances/genetics
- Intercellular Signaling Peptides and Proteins
- Mice
- Oxidative Stress/drug effects
- Oxidative Stress/genetics
- Prolactin
- Promoter Regions, Genetic
- RNA, Messenger/genetics
- RNA, Messenger/isolation & purification
- Transcription, Genetic/drug effects
- Transcription, Genetic/genetics
- Vanadates/metabolism
- Vanadates/toxicity
- beta 2-Microglobulin/genetics
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Affiliation(s)
- C L Parfett
- Mutagenesis Section, Environmental Health Directorate, Health Canada, Ottawa, Ontario
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17
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Abstract
Transcripts from the murine gene family proliferin, which are increased by a wide assortment of chemical promoters of C3H10T1/2 cell morphological transformation, were shown to be induced by tri-n-butyltin chloride at concentrations above 50 nM. Two-stage transformation assays, with 3-methylcholanthrene as inducer and tri-n-butyltin chloride as promoter, were performed to determine if promotion of morphological transformation and proliferin induction were properties shared by this compound. Tri-n-butyltin chloride synergistically enhanced focus formation at concentrations ranging from 20 to 75 nM. Di-n-butyltin dichloride, n-butyltin trichloride and tin (II) chloride, but not tin (IV) chloride, were also effective inducers of proliferin. Changes in patterns of TPA-inducible, secreted proteins, including those likely to be proliferin, were detected following organotin treatment of confluent monolayers. Tri-n-butyltin chloride resembles other agents active as promoters in C3H10T1/2 two-stage transformation assays by possessing an ability to induce proliferin expression.
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Affiliation(s)
- C L Parfett
- Mutagenesis Section, Environmental Health Directorate, Health and Welfare Canada, Tunney's Pasture, Ottawa, Ontario
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18
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Wong P, MacDonald IM, Sood R, Smith C, Pilon R, Tenniswood M. Identification and partial characterization of a candidate gene for X-linked retinopathies using a lateral approach. Genomics 1993; 15:467-71. [PMID: 8468040 DOI: 10.1006/geno.1993.1096] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Using library to library cross-screening we have identified a number of genomic clones that harbor X-linked sequences expressed in the human choroid/retina. We describe the characterization of one of these, designated XEH.8 (DXS542), which is localized to Xp11.3-q12. Isolation, partial sequencing, and Northern analysis of the cognate cDNA (XEH.8c), has shown that the cDNA has some homology to the dystrophin gene and hybridizes to a 10-kb mRNA present in the choroid and retina but not in fibroblasts. This expressed sequence maps to the same region of the X chromosome as several known X-linked ophthalmic diseases, including Norrie disease, retinitis pigmentosa 2, congenital night blindness and Aland Island eye disease.
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Affiliation(s)
- P Wong
- Department of Biochemistry, University of Ottawa, Ontario, Canada
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19
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Hageman J, Baecke C, Ebskamp M, Pilon R, Smeekens S, Weisbeek P. Protein Import into and Sorting inside the Chloroplast Are Independent Processes. Plant Cell 1990; 2:479-494. [PMID: 12354964 PMCID: PMC159904 DOI: 10.1105/tpc.2.5.479] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Plastocyanin is a nuclear-encoded chloroplast thylakoid lumen protein that is synthesized in the cytoplasm with a large N-terminal extension (66 amino acids). Transport of plastocyanin involves two steps: import across the chloroplast envelope into the stroma, followed by transfer across the thylakoid membrane into the lumen. During transport the N-terminal extension is removed in two parts by two different processing proteases. In this study we examined the functions of the two cleaved parts, C1 and C2, in the transport pathway of plastocyanin. The results show that C1 mediates import into the chloroplast. C1 is sufficient to direct chloroplast import of mutant proteins that lack C2. It is also sufficient to direct import of a nonplastid protein and can be replaced functionally by the transit peptide of an imported stromal protein. C2 is a prerequisite for intraorganellar routing but is not required for chloroplast import. Deletions in C2 result in accumulation of intermediates in the stroma or on the outside of the thylakoids. The fact that C1 is functionally equivalent to a stromal-targeting transit peptide shows that plastocyanin is imported into the chloroplast by way of the same mechanism as stromal proteins, and that import into and routing inside the chloroplasts are independent processes.
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Affiliation(s)
- J. Hageman
- Department of Molecular Cell Biology and Institute of Molecular Biology, University of Utrecht, Padualaan 8, NL 3584 CH Utrecht, The Netherlands
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Abstract
Plastocyanin is a nuclear-encoded protein that is functional in the thylakoid lumen of the chloroplast. It is synthesized in the cytoplasm as a precursor with an N-terminal transit peptide of 66 amino acids. Its transport route involves two steps, import into the chloroplasts and subsequent routing over the thylakoid membrane into the lumen. Concomitant with the transport, the transit peptide is removed in two successive steps. The transit peptide consists of two functionally different domains. In this study we examine to what extent each domain is involved in import and routing and how far these two processes are linked. For this purpose we made deletions in the N-terminal and C-terminal part of the transit peptide and fusion proteins which only contain one of these parts. The results show that the N-terminal part of the transit peptide is responsible for import into the chloroplast. The N-terminal 43 amino acids are sufficient to direct other proteins into the stroma. The C-terminal part of the transit peptide is a prerequisite for routing inside the chloroplast but not for import. When deletions are made in this part, the transport of plastocyanin stops after import and the intermediate accumulates in the stroma or on the outside of the thylakoids. Transgenic tomato plants that constitutively express a foreign plastocyanin gene were used to study protein transport in different tissues. Normally, expression of endogenous plastocyanin genes in plants is restricted to photosynthetic tissues only. However, in the transgenic plants this foreign plastocyanin protein is found in all tissues examined. The protein is transported into the local plastids of these tissues and it is processed to the mature size. We conclude that plastids of developmentally different tissues are capable of importing precursor proteins that are normally not found in these tissues. Most likely such plastids, though functionally and morphologically differentiated, have similar or identical protein import mechanisms when compared to the chloroplasts in green tissue. The precursor of ferredoxin was expressed in Escherichia coli. Surprisingly the precursor interacts with the cytoplasmic membrane and is translocated across this membrane. The unprocessed precursor accumulates in the periplasm.
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Affiliation(s)
- P Weisbeek
- Department of Molecular Cell Biology, University of Utrecht, The Netherlands
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Abstract
An electrophoretic mutation of bacteriophage T4, eph1, appears to code for a missense hoc (highly antigenic outer capsid) protein. This is based on the observation that particles lacking hoc protein (hoc- particles), after incubation in a crude extract of Escherichia coli infected with phage carrying the eph1 mutation acquired the electrophoretic mobility of the eph1 strain (the electrophoretic mobility of the eph1 strain itself is slower than that of hoc- particles). Thus, it is likely that during infection of E. coli with the eph1 strain, a hoc protein is made that has a lower negative charge than normal hoc protein but can nevertheless bind to particles lacking hoc protein. These results confirm that eph1 is a hoc mutation.
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Childs JD, Ellison MJ, Pilon R. Formation of 5-hydroxymethylcytosine-containing pyrimidine dimers in UV-irradiated bacteriophage T4 DNA. Photochem Photobiol 1983; 37:513-9. [PMID: 6348807 DOI: 10.1111/j.1751-1097.1983.tb04510.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Field J, Muir D, Pilon R, Sinclair M, Dodwell P. Infants' orientation to lateral sounds from birth to three months. Child Dev 1980; 51:295-8. [PMID: 7363744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Head turning to off-centered sound was videotaped monthly in a group of infants during their first 3 months of life. Infants turned reliably toward the sound at birth and at 1 and 3 months of age. They failed to respond reliably at 2 months due to an increase in no-turn responses. Potential explanations for the temporary decline in orientation responses to sound are discussed.
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Abstract
The infrared multiphoton chemistry of CF3D has been investigated in the ν2 and ν5 bands. The primary dissociation step forms DF and CF2. The major sink for the biradical is dimerization to form C2F4; this process preserves the 13C/12C isotopic selectivity which is reasonably high (α ≈ 20). The isotopic selectivity for 2H/1H is impaired by some scrambling reaction involving excited substrate. The possible nature of this scrambling reaction is discussed. In comparison with other CF3X systems (X = I, Br, Cl), CF3D is difficult to decompose, having low dissociation probability, and appears to decompose only after collisional activation.
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Hackett PA, Gauthier M, Willis C, Pilon R. The selective decomposition of CF3 13COCF3 molecules at natural abundance: Multiphoton dissociation at threshold. J Chem Phys 1979. [DOI: 10.1063/1.438133] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Drouin M, Gauthier M, Pilon R, Hackett P, Willis C. Enrichment of carbon-13 in the products of the multiphoton dissociation of CF3X Compounds. Chem Phys Lett 1978. [DOI: 10.1016/0009-2614(78)85699-1] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Gauthier M, Hackett PA, Drouin M, Pilon R, Willis C. Carbon-13 enrichment in the room temperature multiphoton decomposition of CF3Br. CAN J CHEM 1978. [DOI: 10.1139/v78-365] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
High isotopic selectivities have been observed in the multiphoton decomposition of CF3Br at room temperature. Photolysis of natural abundance CF3Br gives C2F6 enriched to 42% in carbon-13. This is higher than observed for CF3I even at very low temperatures.
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Sigal JJ, Lasry JC, Guttman H, Chagoya L, Pilon R. Some stable characteristics of family therapists' interventions in real and simulated therapy sessions. J Consult Clin Psychol 1977. [PMID: 845302 DOI: 10.1037//0022-006x.45.1.23] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Sigal JJ, Lasry JC, Guttman H, Chagoya L, Pilon R. Some stable characteristics of family therapists' interventions in real and simulated therapy sessions. J Consult Clin Psychol 1977; 45:23-6. [PMID: 845302 DOI: 10.1037/0022-006x.45.1.23] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Lafont J, Pilon R. Influence of glucocorticoids on some morphological and biochemical aspects of rat small intestinal mucosa. Biochim Biophys Acta Gen Subj 1975; 392:288-98. [PMID: 165835 DOI: 10.1016/0304-4165(75)90010-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Glucocorticoid administration (5 mg/day per 100 g of body weight) to month-old rats elicited a reduction of maltase and alkaline phosphatase. Corticotrophic stimulation on month-old rats elicited a specific rise in maltase and alkaline phosphatase activities, total protein content remaining unchanged. Immunological, histological, radioautographical and biochemical studies have shown that these two opposing phenomena do not depend on enzyme activation, on membrane stabilisation, or on modifications of proliferative parameters of the intestinal epithelium. They appear rather to derive from the same origin, i.e. the action of glucocorticoids on the enterocyte differentiation.
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Pilon R, Dupuis C, Morais R. Studies on liver mitochondrial 5'-endonuclease activity in rats fed carcinogenic amines and on their binding to mitochondrial proteins. Chem Biol Interact 1974; 8:371-8. [PMID: 4211001 DOI: 10.1016/0009-2797(74)90043-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Colin R, Dossa J, Baillat X, Pilon R. [Tissue preservation by freezing with liquid nitrogen. Technics. Current practical applications]. Chirurgie 1972; 98:325-32. [PMID: 5071730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Puech A, Pagès A, Dermenghem M, Pilon R, Chavanette F. [Diffuse neoplastic lymphatic invasion. Ménétrier's syndrome]. Montp Med 1965; 67:75-86. [PMID: 5849653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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