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Audet F, Donnard M, Panossian A, Bernier D, Pazenok S, Leroux FR. New Chemical Transformations Involving SO 2 F 2 -Mediated Alcohol Activation. CHEM REC 2023; 23:e202300107. [PMID: 37236146 DOI: 10.1002/tcr.202300107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 05/02/2023] [Indexed: 05/28/2023]
Abstract
Sulfuryl fluoride is a gas produced on a multi-ton scale for its use as a fumigant. In the last decades, it has gained interest in organic synthesis as a reagent with unique properties in terms of stability and reactivity when compared to other sulfur-based reagents. Sulfuryl fluoride has not only been used for sulfur-fluoride exchange (SuFEx) chemistry but also encountered applications in classic organic synthesis as an efficient activator of both alcohols and phenols, forming a triflate surrogate, namely a fluorosulfonate. A long-standing industrial collaboration in our research group drove our work on the sulfuryl fluoride-mediated transformations that will be highlighted below. We will first describe recent works on metal-catalyzed transformations from aryl fluorosulfonates while emphasizing the one-pot processes from phenol derivatives. In a second section, nucleophilic substitution reactions on polyfluoroalkyl alcohols will be discussed and the value of polyfluoroalkyl fluorosulfonates in comparison to alternative triflate and halide reagents will be brought to light.
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Affiliation(s)
- Florian Audet
- Laboratoire d'Innovation Moléculaire et Applications (UMR7042), Université de Strasbourg, Université de Haute-Alsace, CNRS, 25 rue Becquerel, 67000, Strasbourg, France
| | - Morgan Donnard
- Laboratoire d'Innovation Moléculaire et Applications (UMR7042), Université de Strasbourg, Université de Haute-Alsace, CNRS, 25 rue Becquerel, 67000, Strasbourg, France
| | - Armen Panossian
- Laboratoire d'Innovation Moléculaire et Applications (UMR7042), Université de Strasbourg, Université de Haute-Alsace, CNRS, 25 rue Becquerel, 67000, Strasbourg, France
| | - David Bernier
- Bayer S.A.S., 14 impasse Pierre Baizet, 69263, Lyon, France
| | - Sergii Pazenok
- Bayer CropScience AG, Alfred Nobel Straße 50, 40789, Monheim, Germany
| | - Frédéric R Leroux
- Laboratoire d'Innovation Moléculaire et Applications (UMR7042), Université de Strasbourg, Université de Haute-Alsace, CNRS, 25 rue Becquerel, 67000, Strasbourg, France
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Plaçais C, Kaldas SJ, Donnard M, Panossian A, Bernier D, Pazenok S, Leroux FR. Ruthenium-catalyzed Synthesis of Aryl and Alkenyl Halides from Fluorosulfonates. Chemistry 2023:e202301420. [PMID: 37154152 DOI: 10.1002/chem.202301420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 05/05/2023] [Accepted: 05/08/2023] [Indexed: 05/10/2023]
Abstract
Aryl and alkenyl halides are widely used as key intermediates in organic synthesis, particularly for the formation of organometallic reagents or as radical precursors. They are also found in pharmaceutical and agrochemical ingredients. In this work, we report the synthesis of aryl and alkenyl halides from the corresponding fluorosulfonates using commercially available ruthenium catalysts. Notably, this is the first conversion of phenols to aryl halides that is efficient with chloride, bromide, and iodide. Fluorosulfonates are readily prepared using sulfuryl fluoride (SO2F2) and less expensive substitutes for triflates. Although aryl fluorosulfonates and their reactions are well known, this is the first report of an efficient coupling of alkenyl fluorosulfonates. To finish, we have demonstrated, by means of representative examples, that the reaction is possible in a one-pot process, starting directly from the phenol or aldehyde.
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Affiliation(s)
- Clotilde Plaçais
- Université de Strasbourg: Universite de Strasbourg, UMR7042-LIMA, FRANCE
| | - Sherif J Kaldas
- Bayer AG, Chemical Process Development, Active Ingredient Manufacturing Innovation, GERMANY
| | - Morgan Donnard
- Université de Strasbourg: Universite de Strasbourg, UMR7042-LIMA, FRANCE
| | - Armen Panossian
- Université de Strasbourg: Universite de Strasbourg, UMR7042-LIMA, FRANCE
| | | | | | - Frederic R Leroux
- Université de Strasbourg: Universite de Strasbourg, UMR7042-LIMA, 25 Rue Becquerel, 67000, Strasbourg, FRANCE
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Santos L, Audet F, Donnard M, Panossian A, Vors JP, Bernier D, Pazenok S, Leroux FR. Traceless N-Polyfluoroalkylation of Weakly Nucleophilic Nitrogen Containing Compounds. Chemistry 2023:e202300792. [PMID: 36916477 DOI: 10.1002/chem.202300792] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 03/14/2023] [Accepted: 03/14/2023] [Indexed: 03/16/2023]
Abstract
Here we report an efficient access to high-value N-polyfluoroalkyl anilines, primary polyfluoroalkylamines and N,N-bis(polyfluoroalkyl)amines, via N-polyfluoroalkylation of sulfonamides and phthalimide derivatives using sulfuryl fluoride (SO2F2). The in situ formation of polyfluoroalkyl fluorosulfonates from commercially available fluorinated alcohols and economical sulfuryl fluoride is highly advantageous given that some polyfluoroalkyl halides are ozone-depleting substances (ODS) regulated by the Montreal protocol. This general method is applied to the polyfluoroalkylation of a variety of sulfonamides, N-sulfonyl carbamates and phthalimide with a wide tolerance of functional groups. The process thus provides viable access for industry to N-(polyfluoroalkyl)anilines as well as primary and secondary N-(polyfluoroalkyl)amines, which are very valuable but not easily accessible building blocks for life science applications.
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Affiliation(s)
- Laura Santos
- Université de Strasbourg: Universite de Strasbourg, UMR7042-LIMA, FRANCE
| | - Florian Audet
- Université de Strasbourg: Universite de Strasbourg, UMR7042-LIMA, FRANCE
| | - Morgan Donnard
- Université de Strasbourg: Universite de Strasbourg, UMR7042-LIMA, FRANCE
| | - Armen Panossian
- Université de Strasbourg: Universite de Strasbourg, UMR7042-LIMA, FRANCE
| | | | | | | | - Frederic R Leroux
- University of Strasbourg, UMR7042-LIMA, 25 Rue Becquerel, 67000, Strasbourg, FRANCE
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Schwid M, Gray M, Alnuaimi M, Dubsky H, Duggan N, Bernier D, Dashti M, Fischetti C, Goldsmith A, Selame L. 353 The Use of Simulation Ultrasound to Train Emergency Clinicians in Transvaginal Ultrasound. Ann Emerg Med 2022. [DOI: 10.1016/j.annemergmed.2022.08.382] [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: 11/28/2022]
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Sabourin A, Dufour J, Vors JP, Bernier D, Montchamp JL. Synthesis of Carbon‐ and Nitrogen‐Substituted 5‐ and 6‐Membered Benzo‐Phostams. European J Org Chem 2022. [DOI: 10.1002/ejoc.202200141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Axel Sabourin
- Texas Christian University Chemistry and Biochemistry UNITED STATES
| | | | | | | | - Jean-Luc Montchamp
- Texas Christian University Department of Chemistry and Biochemistry 2800 South University DriveSid Richardson Building Room 425 76129 Fort Worth UNITED STATES
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Sabourin A, Dufour J, Vors JP, Bernier D, Montchamp JL. Synthesis of P-Substituted 5- and 6-Membered Benzo-Phostams: 2,3-Dihydro-1 H-1,2-benzazaphosphole 2-Oxides and 2,3-Tetrahydro-1 H-1,2-benzazaphosphinine 2-Oxides. J Org Chem 2021; 86:14684-14694. [PMID: 34633805 DOI: 10.1021/acs.joc.1c01501] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [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
Several approaches were developed for the preparation of phosphorus-substituted 5- and 6-membered benzophostams. Carbodiimide-promoted cyclization of zwitterionic aminophosphinates derived from a nitrobenzene precursor accomplished the cyclization in good yields. Alternatively, a novel copper-catalyzed cross-coupling between a phosphonamide and a bromobenzene precursor produced the heterocycles in moderate to good yields. Three different methods are compared for the synthesis of the P-ethoxy-substituted 5-membered benzophostam.
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Affiliation(s)
- Axel Sabourin
- Department of Chemistry and Biochemistry, TCU Box 298860, Texas Christian University, Fort Worth, Texas 76129, United States
| | - Jeremy Dufour
- Bayer SAS, Centre de Recherche La Dargoire, 14-20 impasse Pierre Baizet, CEDEX, Lyon 69263, France
| | - Jean-Pierre Vors
- Bayer SAS, Centre de Recherche La Dargoire, 14-20 impasse Pierre Baizet, CEDEX, Lyon 69263, France
| | - David Bernier
- Bayer SAS, Centre de Recherche La Dargoire, 14-20 impasse Pierre Baizet, CEDEX, Lyon 69263, France
| | - Jean-Luc Montchamp
- Department of Chemistry and Biochemistry, TCU Box 298860, Texas Christian University, Fort Worth, Texas 76129, United States
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Santos L, Donnard M, Panossian A, Vors JP, Jeschke P, Bernier D, Pazenok S, Leroux FR. SO 2F 2-Mediated N-Alkylation of Imino-Thiazolidinones. J Org Chem 2021; 87:2012-2021. [PMID: 34355900 DOI: 10.1021/acs.joc.1c01247] [Citation(s) in RCA: 1] [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 N-alkylation of ambident and weakly nucleophilic imino-thiazolidinones has been developed via substitution with alkyl fluorosulfonates. These reactive electrophiles are obtained through the transformation of nontoxic, economic, and commercially available alcohol derivatives on exposure to SO2F2 gas. The use of electron-withdrawing groups and DMAc as solvent affords a (Z)- and N-endocyclic selectivity for the easy introduction of a variety of alkyl and polyfluoroalkyl chains.
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Affiliation(s)
- Laura Santos
- University of Strasbourg, University of Haute-Alsace, CNRS, UMR 7042-LIMA, ECPM, 25 Rue Becquerel, 67087 Strasbourg, France
| | - Morgan Donnard
- University of Strasbourg, University of Haute-Alsace, CNRS, UMR 7042-LIMA, ECPM, 25 Rue Becquerel, 67087 Strasbourg, France
| | - Armen Panossian
- University of Strasbourg, University of Haute-Alsace, CNRS, UMR 7042-LIMA, ECPM, 25 Rue Becquerel, 67087 Strasbourg, France
| | - Jean-Pierre Vors
- Bayer S.A.S., 14 Impasse Pierre Baizet, BP99163, 69263 Lyon, Cedex 09, France
| | - Peter Jeschke
- Bayer CropScience AG, Alfred-Nobel-Strasse 50, 40789 Monheim, Germany
| | - David Bernier
- Bayer S.A.S., 14 Impasse Pierre Baizet, BP99163, 69263 Lyon, Cedex 09, France
| | - Sergii Pazenok
- Bayer CropScience AG, Alfred-Nobel-Strasse 50, 40789 Monheim, Germany
| | - Frédéric R Leroux
- University of Strasbourg, University of Haute-Alsace, CNRS, UMR 7042-LIMA, ECPM, 25 Rue Becquerel, 67087 Strasbourg, France
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Plaçais C, Donnard M, Panossian A, Vors JP, Bernier D, Pazenok S, Leroux FR. Synthesis of 3-Amino-5-fluoroalkylfurans by Intramolecular Cyclization. Org Lett 2021; 23:4915-4919. [PMID: 34080423 DOI: 10.1021/acs.orglett.1c01672] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [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
A synthesis to access rarely described 3-amino-5-fluoroalkylfurans has been developed by cyclization of easily accessible fluorovinamides. This method is rapid and simple and affords the desired furans as hydrochloride salts in quantitative or nearly quantitative yields. It is compatible with four different fluorinated groups (-CF3, -CF2CF3, -CHF2, and -CF2Cl) and a wide range of substituents on the amine.
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Affiliation(s)
- Clotilde Plaçais
- Université de Strasbourg, Université de Haute-Alsace, CNRS, UMR 7042-LIMA, ECPM, 25 Rue Becquerel, Strasbourg 67087, France
| | - Morgan Donnard
- Université de Strasbourg, Université de Haute-Alsace, CNRS, UMR 7042-LIMA, ECPM, 25 Rue Becquerel, Strasbourg 67087, France
| | - Armen Panossian
- Université de Strasbourg, Université de Haute-Alsace, CNRS, UMR 7042-LIMA, ECPM, 25 Rue Becquerel, Strasbourg 67087, France
| | - Jean-Pierre Vors
- Bayer S.A.S., 14 Impasse Pierre Baizet, BP99163, 69263 Lyon Cedex 09, France
| | - David Bernier
- Bayer S.A.S., 14 Impasse Pierre Baizet, BP99163, 69263 Lyon Cedex 09, France
| | - Sergii Pazenok
- Bayer CropScience AG, Alfred-Nobel-Strasse 50, 40789 Monheim, Germany
| | - Frédéric R Leroux
- Université de Strasbourg, Université de Haute-Alsace, CNRS, UMR 7042-LIMA, ECPM, 25 Rue Becquerel, Strasbourg 67087, France
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Santymire RM, Adkin A, Bernier D, Hill B. Validating the use of fecal glucocorticoid metabolite analysis to assess the adrenocortical activity of the zoo-housed Sichuan takin (Budorcas taxicolor tibetana). Zoo Biol 2021; 40:479-484. [PMID: 33905549 DOI: 10.1002/zoo.21612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 01/28/2021] [Accepted: 04/05/2021] [Indexed: 11/06/2022]
Abstract
With limited information known about the zoo-housed Sichuan takin (Budorcas taxicolor tibetana), there is a need to gain more knowledge about their basic physiology to be able to better assess their well-being. Our goal was to develop noninvasive methods to evaluate stress physiology in the Sichuan takins housed under human care. The objectives were: (1) validate the use of fecal glucocorticoid metabolite (FGM) analysis to monitor adrenocortical activity and (2) determine the relationship between FGM concentrations and changes in various factors including environmental conditions, reproductive hormones, and social factors. Three (one male and two females) adult Sichuan takins were included in the study from Lincoln Park Zoo. A cortisol enzyme immunoassay was used to analyze FGM from samples that were collected 2-4 times per week. FGM was biochemically validated in the laboratory and biologically validated using pregnancy and parturition. Results showed that 1 day after birth one female had a more than a six-fold increase in FGM. A positive relationship (p < .05) was observed between FGM and temperature for two of the three takins. Finally, FGM values tended to increase during times when aggression (p = .09) and reproductive (p = .08) behaviors were observed. In conclusion, environmental, reproductive, and behavioral factors could affect adrenocortical activity in zoo-housed Sichuan takins; therefore, these methods can be used to assist in the management and conservation of this threatened species both in zoos and potentially in the wild.
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Affiliation(s)
- Rachel M Santymire
- Conservation and Science Department, Davee Center for Epidemiology and Endocrinology, Lincoln Park Zoo, Chicago, Illinois, USA
| | - Angie Adkin
- Department of Physiological Sciences, University of Florida, Gainesville, Florida, USA
| | - David Bernier
- Animal Care Department, Lincoln Park Zoo, Chicago, Illinois, USA
| | - Brandy Hill
- Department of Medical Laboratory Science, Rush University, Chicago, Illinois, USA
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Abstract
The functionalization of 3-(difluoromethyl)pyridine has been developed via direct deprotonation of -CHF2 with a lithiated base and subsequent trapping with various electrophiles in THF. In situ quenching gives access to 3-pyridyl-CF2-SiMe2Ph as a new silylated compound, which can be postfunctionalized with a fluoride source to obtain a larger library of 3-(difluoroalkyl)pyridines that could not be accessed via direct deprotonation.
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Affiliation(s)
- Laura Santos
- Université de Strasbourg, Université de Haute-Alsace, CNRS, UMR 7042-LIMA, ECPM, 25 Rue Becquerel, Strasbourg 67087, France
| | - Armen Panossian
- Université de Strasbourg, Université de Haute-Alsace, CNRS, UMR 7042-LIMA, ECPM, 25 Rue Becquerel, Strasbourg 67087, France
| | - Morgan Donnard
- Université de Strasbourg, Université de Haute-Alsace, CNRS, UMR 7042-LIMA, ECPM, 25 Rue Becquerel, Strasbourg 67087, France
| | - Jean-Pierre Vors
- Bayer S.A.S., 14 Impasse Pierre Baizet, BP99163, 69263 Lyon Cedex 09, France
| | - Sergii Pazenok
- Bayer CropScience AG, Alfred-Nobel-Strasse 50, 40789 Monheim, Germany
| | - David Bernier
- Bayer S.A.S., 14 Impasse Pierre Baizet, BP99163, 69263 Lyon Cedex 09, France
| | - Frédéric R Leroux
- Université de Strasbourg, Université de Haute-Alsace, CNRS, UMR 7042-LIMA, ECPM, 25 Rue Becquerel, Strasbourg 67087, France
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Howell-Stephens J, Bernier D, Brown JS, Mulkerin D, Santymire RM. Using non-invasive methods to characterize gonadal hormonal patterns of southern three-banded armadillos (Tolypeutes matacus) housed in North American zoos. Anim Reprod Sci 2013; 138:314-23. [PMID: 23541612 DOI: 10.1016/j.anireprosci.2013.02.004] [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] [Received: 09/21/2011] [Revised: 01/29/2013] [Accepted: 02/12/2013] [Indexed: 12/01/2022]
Abstract
Understanding the basic reproductive biology and limitations to successful breeding of the southern three-banded armadillo (Tolypeutes matacus) is necessary to maintain viable zoo populations. Our objectives were to: 1) describe the reproductive biology using non-invasive, fecal hormone analysis; 2) assess influence of season on gonadal hormonal patterns in both the sexes; 3) characterize reproductive cyclicity and pregnancy in the female; and 4) characterize the onset of sexual maturity in males. Nineteen armadillos were monitored including: 13 (7 males, 6 females) from Lincoln Park Zoo and six (3 males, 3 females) from San Antonio Zoological Garden. Fecal samples (n=5220; 275/animal/yr) were collected 5 to 7 times a week for 1 year. Hormones were extracted from feces and analyzed for progestagen (females) and androgen (males) metabolite concentrations using enzyme immunoassays. Mean estrous cycle length (26.4±1.3 days) did not vary (P<0.05) among individuals (n=9). Mean gestation length (n=3) was 114.0±0.6 days long with mean fecal progestagen metabolites increasing 10-fold during pregnancy. Seasons did not influence (P<0.05) fecal androgen or progestagen metabolites. These data can assist with management decisions, which will directly affect the success of this species in zoos.
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Affiliation(s)
- J Howell-Stephens
- Department of Biological Sciences, University of Illinois, Chicago, IL 60607, USA.
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Howell-Stephens JA, Brown JS, Bernier D, Mulkerin D, Santymire RM. Characterizing adrenocortical activity in zoo-housed southern three-banded armadillos (Tolypeutes matacus). Gen Comp Endocrinol 2012; 178:64-74. [PMID: 22537671 DOI: 10.1016/j.ygcen.2012.04.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2011] [Revised: 03/22/2012] [Accepted: 04/09/2012] [Indexed: 11/22/2022]
Abstract
Improving the husbandry in the southern three-banded armadillo (Tolypeutes matacus) through gaining knowledge of its stress physiology is imperative to maintaining a healthy, zoo-housed population. Our objectives were to: 1) validate the use of fecal hormone analysis for monitoring adrenocortical activity using both an adrenocorticotropic hormone (ACTH) challenge and biological events; and 2) characterize longitudinal adrenocortical activity in male and female southern three-banded armadillos. An ACTH injection was given intra-muscularly to one male (4IU/kg; 5.6IU total) and one female (5.5IU/kg; 8IU total) southern three-banded armadillo. Fecal samples were collected 1 day pre- and continued 5 days post-ACTH to capture the physiological response measured by elevated fecal glucocorticoid metabolites (FGM) to validate these techniques. Additionally, natural and routine events, including pairing individuals for breeding and veterinary procedures/handling, were used to biologically validate these techniques. To characterize adrenocortical activity, fecal samples (∼3025 total; n=275/animal/yr) were collected from 11 (5 males; 6 females) southern three-banded armadillos 5-7 times a week for 1 year at Lincoln Park Zoo (Chicago, IL). A cortisol enzyme immunoassay was used for FGM analysis. The ACTH challenge in the male resulted in a twofold increase of FGM (1123.2±36.2 ng/g dry feces) above baseline (675.7±10.0 ng/g dry feces) at approximately 54-94h post- injection. The female exhibited a twofold increase (1635.4 ng/g dry feces) over baseline FGMs (608.5±12.3 ng/g dry feces) approximately 30h post-injection. Reproductive behaviors and veterinary procedures resulted in elevated FGM concentrations from all individuals except for one male. The longitudinal characterization demonstrated that sex and season did not influence (P<0.05) FGM concentrations. Individuals were highly variable with mean FGM concentration of 2010.1±862.4 ng/g dry feces (range, 816.3-7889.1 ng/g dry feces). Mean FGM baseline concentration was 878.5±201.8ng/g dry feces (range, 475.2-1955.5 ng/g dry feces) with a mean elevated FGM concentrations of 2694.3±1111.4 ng/g dry feces (range, 1110.3-10,683.3 ng/g dry feces). This study provides the foundation for future research on how the environment directly affects the adrenocortical activity in this species of armadillo.
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Dawson AJ, Hryshko M, Konkin D, Bal S, Bernier D, Tomiuk M, Burnett S, Frosk P, Chodirker BN, Chun K. Origin of a prenatal mosaic supernumerary neocentromeric derivative chromosome 13 determined by QF-PCR. Fetal Diagn Ther 2012; 33:75-8. [PMID: 22614064 DOI: 10.1159/000337537] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2012] [Accepted: 02/14/2012] [Indexed: 11/19/2022]
Abstract
Neocentromeres are mitotically stable human derivative centromeres without alpha-satellite DNA which are able to provide stability to rearranged chromosome fragments that would otherwise be acentric and rapidly lost. A female fetus was found to be mosaic for a supernumerary marker chromosome: 47,XX,+mar[3]/46,XX[36]. The marker was identified by fluorescence in situ hybridization and G-band as an inversion duplication of 13q21→13qter, with a neocentromere present at 13q21, in approximately 9% of colonies examined. Parental blood karyotypes were normal. QF-PCR performed on blood samples from both parents and the second amniotic fluid sample showed evidence of a second maternal allele at markers D13S258 (13q21) and D13S628 (13q31-q32), indicating formation at maternal meiosis I/II. This is the first reported case where the detection and origin of a low-level mosaic prenatal neo(13) were confirmed by QF-PCR.
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Affiliation(s)
- A J Dawson
- Cytogenetics Laboratory, Diagnostic Services of Manitoba, Winnipeg, Manitoba, Canada.
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15
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Brückner R, Bernier D. Novel Synthesis of
Naturally Occurring Pulvinones: A Heck Coupling, Transesterification,
and Dieckmann Condensation Strategy. SYNTHESIS-STUTTGART 2009. [DOI: 10.1055/s-0028-1088054] [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: 10/19/2022]
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Abstract
An improved procedure for the preparation of enamine N-oxides involving aminolysis of epoxides, chlorination, N-oxidation, and dehydrochlorination is described. Although isolated beta-chloroamine N-oxides are prone to rearrangements when isolated, these side reactions can be slowed by the presence of stabilizing organic acids. The scope and limitations of this strategy are discussed.
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Affiliation(s)
- David Bernier
- School of Chemistry, The University of Nottingham, Nottingham, United Kingdom
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Saucier L, Bernier D, Bergeron R, Giguère A, Méthot S, Faucitano L. Effect of feed texture, meal frequency and pre-slaughter fasting on behaviour, stomach content and carcass microbial quality in pigs. Can J Anim Sci 2007. [DOI: 10.4141/a06-072] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
In this study, behaviour in lairage, weight and composition of stomach contents and carcass microbial contamination were studied in 96 barrows assigned to the following treatments: feed texture (FT; mash vs. pellets), meal frequency (MF; 2 vs. five meals per day) and fasting time (WT; 4, 14 and 24 h) according to a 2 × 2 × 3 factorial design. Pigs fed two meals had heavier stomach weights at slaughter than those fed five times per day (P = 0.01). An interaction was found between WT and FT (P = 0.002) for stomach weight. With respect to the contamination of the mouth, total aerobic mesophilic counts were higher than 104 cfu cm-2 but not significantly different between treatments. Coprophagy behaviour in lairage was not correlated with mouth contamination at slaughter. The treatment resulting in the lowest Escherichia coli counts on the thoracic area was feeding the pigs pellets five times per day followed by a 24-h fast. In contrast, the highest E. coli counts were observed in pigs fed mash five times per day followed by a 4-h fast. Comparison a posteriori of these two extreme scenarios yielded a P value of 0.03. Key words: Animal behaviour, carcass hygiene, fasting, feeding, pigs, stomach
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Brückner R, Bernier D. Novel Synthesis of Naturally Occurring Pulvinones: A Heck Coupling, Transesterification, and Dieckmann Condensation Strategy. SYNTHESIS-STUTTGART 2007. [DOI: 10.1055/s-2007-983803] [Citation(s) in RCA: 7] [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: 10/23/2022]
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19
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Brückner R, Bernier D, Moser F. Synthesis and Cyclization of 3-Aryl-2-(arylacetoxy)acrylates: A Three-Step Access to Pulvinones. SYNTHESIS-STUTTGART 2007. [DOI: 10.1055/s-2007-983800] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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20
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Shannon J, Bernier D, Rawson D, Woodward S. Direct asymmetric catalytic 1,2-addition of RZnX to aldehydes promoted by AlMe3 and reversal of expected stereochemistry. Chem Commun (Camb) 2007:3945-7. [PMID: 17896041 DOI: 10.1039/b710681e] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [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: 11/21/2022]
Abstract
Addition of AlMe3 to commercial THF solutions of RZnX (R = aryl, functionalised aryl, vinyl; X = Br, I) simultaneously promotes Schlenk equilibria (leading to competent nucleophiles) and the formation of an Al-Zn-ligand catalyst delivering 80-90% ee for Ar(1)CH(OH)Ar(2) formation from aldehydes.
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Affiliation(s)
- Jonathan Shannon
- School of Chemistry, The University of Nottingham, Nottingham, UKNG7 2RD
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21
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Fallouh F, Bernier D, Virieux D, Cristau HJ, Pirat JL. Synthesis of N-(bisphosphonomethyl)-aza-15-Crown-5 and N-(bisphosphonomethyl)-aza-18-Crown-6 Ethers as Artificial Ion Channels: An Approach to Channel-Type Molecular Structures. PHOSPHORUS SULFUR 2006. [DOI: 10.1080/104265090969766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- F. Fallouh
- a Département de Chimie , Université de Damas , Syrie
| | - D. Bernier
- b Laboratoire de Chimie Organique , France
| | - D. Virieux
- b Laboratoire de Chimie Organique , France
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22
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Pérodeau G, Paquette S, Brissette L, St-Pierre C, Bernier D, Duquette A. [Health professionals in part-time employment: the challenge of balancing work and family]. Can J Commun Ment Health 2001; 20:53-74. [PMID: 11599137] [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: 04/17/2023]
Abstract
Looking at the case of occasional part-time nurses, this study highlights the difficulties in balancing work and family that are inherent in nonstandard jobs. Eight focus groups were held, involving 48 nurses in 4 regions of Quebec. Analysis of the data collected reveals that nurses "on call" are particularly affected by overwork and experience great difficulty in balancing their work and family obligations. The participants proposed a variety of solutions, such as establishing day care centres adapted to the needs of nurses on call and instituting a timetable grid for occasional part-time nurses so that they can plan their work hours.
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Affiliation(s)
- G Pérodeau
- Groupe de recherche sur les aspects sociaux de la santé et de la prévention, Université du Québec à Hull, Case postale 1250, succursale B, Hull, Québec, J8Y 3X7, Canada.
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23
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Turbini L, Munie G, Bernier D, Gamalski J, Bergman D. Examining the environmental impact of lead-free soldering alternatives. ACTA ACUST UNITED AC 2001. [DOI: 10.1109/6104.924786] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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24
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Bernier D. [Pedagogy: representation(s) and education in nursing care]. Soins Form Pedagog Encadr 2000:45-8. [PMID: 10734972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
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25
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Abstract
Genetic analyses have revealed the essential role of the murine Hoxa5 gene for the correct specification of the cervical and upper thoracic region of the skeleton, and for the normal organogenesis and function of the respiratory tract, both structures expressing Hoxa5 during embryogenesis. To understand how the expression domains of the Hoxa5 gene are established during development, we have analyzed the cis-acting control regions mediating Hoxa5 gene expression using a transgenic approach. Four transcripts are derived from the Hoxa5 locus. The shortest and most abundant one displays a specific spatio-temporal profile of expression at earlier stages and in more anterior structures along the embryonic axis than the larger forms. We established that an 11.1 kilobase pair (kb) genomic fragment, extending from position -3.8 kb to +7.3 kb relative to Hoxa5 transcription initiation site, was sufficient to reproduce the temporal expression and substantially reconstitute the spatial pattern of the major Hoxa5 transcript. By deletion analyses, we identified a 2.1 kb fragment located downstream of the Hoxa5 gene that possesses mesodermal enhancer activity. Overall, the findings demonstrate that cis-acting regulatory elements essential for the correct expression of the major Hoxa5 transcript are located both upstream and downstream of the Hoxa5 coding sequences.
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Affiliation(s)
- C Larochelle
- Centre de Recherche en Cancérologie de l'Université Laval, Centre Hospitalier Universitaire de Québec, Canada
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26
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Abstract
Genetic analyses have revealed the essential role of the murine Hoxa5 gene for the correct specification of the cervical and upper thoracic region of the skeleton, and for the normal organogenesis and function of the respiratory tract, both structures expressing Hoxa5 during embryogenesis. To understand how the expression domains of the Hoxa5 gene are established during development, we have analyzed the cis-acting control regions mediating Hoxa5 gene expression using a transgenic approach. Four transcripts are derived from the Hoxa5 locus. The shortest and most abundant one displays a specific spatio-temporal profile of expression at earlier stages and in more anterior structures along the embryonic axis than the larger forms. We established that an 11.1 kilobase pair (kb) genomic fragment, extending from position -3.8 kb to +7.3 kb relative to Hoxa5 transcription initiation site, was sufficient to reproduce the temporal expression and substantially reconstitute the spatial pattern of the major Hoxa5 transcript. By deletion analyses, we identified a 2.1 kb fragment located downstream of the Hoxa5 gene that possesses mesodermal enhancer activity. Overall, the findings demonstrate that cis-acting regulatory elements essential for the correct expression of the major Hoxa5 transcript are located both upstream and downstream of the Hoxa5 coding sequences.
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Affiliation(s)
- C Larochelle
- Centre de Recherche en Cancérologie de l'Université Laval, Centre Hospitalier Universitaire de Québec, Canada
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27
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Moineau S, Bernier D, Jobin M, Hébert J, Klaenhammer TR, Pandian S. Production of Monoclonal Antibodies against the Major Capsid Protein of the
Lactococcus
Bacteriophage ul36 and Development of an Enzyme-Linked Immunosorbent Assay for Direct Phage Detection in Whey and Milk. Appl Environ Microbiol 1993; 59:2034-40. [PMID: 16348980 PMCID: PMC182232 DOI: 10.1128/aem.59.7.2034-2040.1993] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The only major structural protein (35 kDa) of the lactococcal small isometric-headed bacteriophage ul36, a member of the P335 species, was isolated from a preparative sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis. Monoclonal antibodies (MAbs) were raised against the denatured 35-kDa protein. Six MAbs were selected and characterized. Western blots (immunoblots) showed that all MAbs recognized the 35 kDa but also a 45 kDa that is in lower concentration in the phage structure. Binding inhibition assays identified five families of MAbs that recognized nonoverlapping epitopes of the 35- and 45-kDa proteins. Immunoelectron microscopy showed that these two proteins are localized within the phage head, therefore indicating that the 35 kDa is a major capsid protein of ul36 and that the 45 kDa is a minor capsid protein. With two MAbs, a sandwich enzyme-linked immunosorbent assay (ELISA) was developed for direct detection of lactococcal phages in whey and milk samples. Whey and milk components, however, interfered with the conduct of the assay. Partial denaturation of milk samples by heat treatment in the presence of SDS and β-mercaptoethanol removed the masking effect and increased the sensitivity of the assay by 100-fold. With the method used here, 10
7
PFU/ml were detected by the ELISA within 2 h without any steps to enrich or isolate bacteriophages.
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Affiliation(s)
- S Moineau
- Centre de Recherche STELA and Département de Sciences et Technologie des Aliments, Université Laval, Pavillon Comtois, Sainte-Foy, Québec, Canada G1K 7P4; Unité de Recherche Inflammation et Immunologie-Rhumatologie, Centre Hospitalier de l'Université Laval, Sainte-Foy, Québec, Canada G1V 4G2 ; and Southeast Dairy Foods Research Center and Department of Food Science, North Carolina State University, Raleigh, North Carolina 27695-7624
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28
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Bernier D, Thomassin H, Allard D, Guertin M, Hamel D, Blaquière M, Beauchemin M, LaRue H, Estable-Puig M, Bélanger L. Functional analysis of developmentally regulated chromatin-hypersensitive domains carrying the alpha 1-fetoprotein gene promoter and the albumin/alpha 1-fetoprotein intergenic enhancer. Mol Cell Biol 1993; 13:1619-33. [PMID: 7680097 PMCID: PMC359474 DOI: 10.1128/mcb.13.3.1619-1633.1993] [Citation(s) in RCA: 17] [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: 01/26/2023] Open
Abstract
During liver development, the tandem alpha 1-fetoprotein (AFP)/albumin locus is triggered at the AFP end and then asymmetrically enhanced; this is followed by autonomous repression of the AFP-encoding gene. To understand this regulation better, we characterized the two early developmental stage-specific DNase I-hypersensitive (DH) sites so far identified in rat liver AFP/albumin chromatin: an intergenic DH-enhancer site and the AFP DH-promoter site. Mutation-transfection analyses circumscribed the DH-enhancer domain to a 200-bp DNA segment stringently conserved among species. Targeted mutations, DNA-protein-binding assays, and coexpression experiments pinpointed C/EBP as the major activatory component of the intergenic enhancer. Structure-function relationships at the AFP DH-promoter site defined a discrete glucocorticoid-regulated domain activated cooperatively by HNF1 and a highly specific AFP transcription factor, FTF, which binds to a steroid receptor recognition motif. The HNF1/FTF/DNA complex is deactivated by glucocorticoid receptors or by the ubiquitous factor NF1, which eliminates HNF1 by competition at an overlapping, high-affinity binding site. We propose that the HNF1-NF1 site might serve as a developmental switch to direct autonomous AFP gene repression in late liver development. We also conclude that the intergenic enhancer is driven by C/EBP alpha primarily to fulfill albumin gene activation functions at early developmental stages. Factor FTF seems to be the key regulator of AFP gene-specific functions in carcinoembryonic states.
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Affiliation(s)
- D Bernier
- Le Centre de recherche en cancérologie, Université Laval, L'Hôtel-Dieu de Québec, Canada
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29
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Boutin Y, Jobin M, Bernier D, Hébert J. Biological activity of monoclonal anti-idiotypic antibody representing the internal image of the major allergenic component of Lolium perenne pollen. Int Arch Allergy Immunol 1993; 102:10-4. [PMID: 7691293 DOI: 10.1159/000236545] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [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] Open
Abstract
Upon immunization with an anti-Lol p I (major allergenic component of Lolium perenne pollen) monoclonal antibody, we have previously produced anti-idiotypic monoclonal antibody (A7H2) displaying some internal image properties. The present study was designated to evaluate the capacity of this anti-idiotypic monoclonal antibody to mimic functionally the antigen by triggering histamine release from basophils of patients allergic to Lol p I. Anti-idiotypic monoclonal antibody, as the antigen, could induce histamine release in a dose-response fashion in all of the atopic patients (6/6). The inhibition of this histamine release by the addition of the idiotype (290A-167) confirmed the specificity of the reaction. Binding inhibition of human IgE to Lol p I demonstrated that the anti-idiotypic antibody recognized an idiotope expressed in the antigen-combining site of IgE molecules. Altogether, these data confirmed the internal properties of our anti-idiotypic antibody and it can mimic the original antigen in its capacity to trigger histamine release.
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Affiliation(s)
- Y Boutin
- Centre de Recherche Inflammation et Immunologie-Rhumatologie, Centre Hospitalier de l'Université Laval, Ste-Foy, Qué., Canada
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30
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Thomassin H, Hamel D, Bernier D, Guertin M, Belanger L. Molecular cloning of two C/EBP-related proteins that bind to the promoter and the enhancer of the alpha 1-fetoprotein gene. Further analysis of C/EBP beta and C/EBP gamma. Nucleic Acids Res 1992; 20:3091-8. [PMID: 1377818 PMCID: PMC312443 DOI: 10.1093/nar/20.12.3091] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.6] [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: 12/26/2022] Open
Abstract
In an attempt to identify proteins that may regulate alpha 1-fetoprotein (AFP) gene expression, we screened a cDNA expression library from neonatal rat liver with two essential cis-elements of the AFP promoter and enhancer. We isolated two cDNAs which were found to correspond to leucine zipper proteins of the CC-AAT/enhancer binding protein (C/EBP) family: C/EBP beta and C/EBP gamma. The three related proteins C/EBP alpha, beta and gamma bind with indistinguishable specificity to multiple DNA sites in the promoter and the enhancer of the AFP gene. In addition, C/EBP beta and C/EBP gamma readily heterodimerize with each other as well as with C/EBP alpha. The mRNAs coding for C/EBP beta and C/EBP gamma are expressed in a wider variety of rat tissues than C/EBP alpha mRNA, including yolk sac and fetal liver. The steady-state levels of C/EBP alpha, beta and gamma mRNAs increase during liver development, in parallel with their respective gene transcriptional rates. The high levels of C/EBP beta and gamma mRNAs in rat yolk sac and fetal liver, where C/EBP alpha is poorly expressed, suggest that C/EBP beta and/or gamma could be preponderant or early regulators of the AFP gene in these tissues.
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Affiliation(s)
- H Thomassin
- Le Centre de Recherche en Cancérologie, l'Université Laval, L'Hôtel-Dieu de Québec, Canada
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31
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Hébert J, Bernier D, Boutin Y, Jobin M, Mourad W. Generation of anti-idiotypic and anti-anti-idiotypic monoclonal antibodies in the same fusion. Support of Jerne's Network Theory. The Journal of Immunology 1990. [DOI: 10.4049/jimmunol.144.11.4256] [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: 01/01/2023]
Abstract
Abstract
Upon immunization of mice with a mAb (290A-167) directed against an epitope of Lol p I (the major allergenic determinant of Lolium perenne), both anti-idiotypic (aId) mAb (Ab2) and anti-aId mAb (Ab3) were produced. The Ab2 displayed the following internal image properties of Lol p I: it can be affinity-purified on an immobilized Id column; its binding to the anti-Lol p I mAb (290A-167) is inhibited by Lol p I; it inhibits in a dose-response fashion the binding of the specific Id to Ag. It is recognized by anti-Lol p I antisera from different species such as mouse, human, and goat. The Ab3 which binds to Lol p I was also produced from the same fusion. This binding was inhibited significantly by aId mAb (Ab2), anti-Lol p I mAb (290A-167) and Lol p I. These data indicate that the two mAb with specificity for Lol p I (290A-167 and Ab3) share similar reactivity to the Ag and that aId mAb is the internal image of the epitope recognized by the Id. We showed also that the capacity of rabbit aId Ab directed against the 290A-167 Id to inhibit the binding of Ab1 and Ab3 to Ag was almost abolished by passage over a Ab3-coated Sepharose column. This would suggest that not only are the two mAb with reactivity to Lol p I (Ab1 and Ab3) directed against identical epitopes, but that they in fact shared identical idiotopes as well. The production of identical mAb upon immunization with either the Ag or the aId mAb supports that the conceptual framework proposed by Jerne finds its biologic application in the course of an immune response.
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Affiliation(s)
- J Hébert
- Unité de Recherche en Inflammation et Immunologie-Rhumatologie, CHUL, Ste-Foy, Canada
| | - D Bernier
- Unité de Recherche en Inflammation et Immunologie-Rhumatologie, CHUL, Ste-Foy, Canada
| | - Y Boutin
- Unité de Recherche en Inflammation et Immunologie-Rhumatologie, CHUL, Ste-Foy, Canada
| | - M Jobin
- Unité de Recherche en Inflammation et Immunologie-Rhumatologie, CHUL, Ste-Foy, Canada
| | - W Mourad
- Unité de Recherche en Inflammation et Immunologie-Rhumatologie, CHUL, Ste-Foy, Canada
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32
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Hébert J, Bernier D, Boutin Y, Jobin M, Mourad W. Generation of anti-idiotypic and anti-anti-idiotypic monoclonal antibodies in the same fusion. Support of Jerne's Network Theory. J Immunol 1990; 144:4256-61. [PMID: 2341720] [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: 12/31/2022]
Abstract
Upon immunization of mice with a mAb (290A-167) directed against an epitope of Lol p I (the major allergenic determinant of Lolium perenne), both anti-idiotypic (aId) mAb (Ab2) and anti-aId mAb (Ab3) were produced. The Ab2 displayed the following internal image properties of Lol p I: it can be affinity-purified on an immobilized Id column; its binding to the anti-Lol p I mAb (290A-167) is inhibited by Lol p I; it inhibits in a dose-response fashion the binding of the specific Id to Ag. It is recognized by anti-Lol p I antisera from different species such as mouse, human, and goat. The Ab3 which binds to Lol p I was also produced from the same fusion. This binding was inhibited significantly by aId mAb (Ab2), anti-Lol p I mAb (290A-167) and Lol p I. These data indicate that the two mAb with specificity for Lol p I (290A-167 and Ab3) share similar reactivity to the Ag and that aId mAb is the internal image of the epitope recognized by the Id. We showed also that the capacity of rabbit aId Ab directed against the 290A-167 Id to inhibit the binding of Ab1 and Ab3 to Ag was almost abolished by passage over a Ab3-coated Sepharose column. This would suggest that not only are the two mAb with reactivity to Lol p I (Ab1 and Ab3) directed against identical epitopes, but that they in fact shared identical idiotopes as well. The production of identical mAb upon immunization with either the Ag or the aId mAb supports that the conceptual framework proposed by Jerne finds its biologic application in the course of an immune response.
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Affiliation(s)
- J Hébert
- Unité de Recherche en Inflammation et Immunologie-Rhumatologie, CHUL, Ste-Foy, Canada
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33
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Hébert J, Bernier D, Mourad W. Detection of auto-anti-idiotypic antibodies to Lol p I (rye I) IgE antibodies in human sera by the use of murine idiotypes: levels in atopic and non-atopic subjects and effects of immunotherapy. Clin Exp Immunol 1990; 80:413-9. [PMID: 2372990 PMCID: PMC1535190 DOI: 10.1111/j.1365-2249.1990.tb03303.x] [Citation(s) in RCA: 18] [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: 12/31/2022] Open
Abstract
Anti-idiotypic antibodies (anti-Id Abs) are involved in the regulation of a number of immune responses including the IgE antibody production. In atopic patients, the increased synthesis of IgE antibodies could be related to a defective production of regulatory anti-Id Abs. In the present study, we first developed a sensitive assay for measuring the levels of anti-Id Abs directed against antibodies specific for Lol p I, the major allergenic determinant of Lolium perenne (rye grass). In this assay, we used previously described murine monoclonal anti-Lol p I antibodies that were shown to share epitopic specificities with human anti-Lol p I IgE and IgG antibodies, thus short-cutting the need for purification of F(ab')2 fragments of human IgG Abs and insuring optimal specificity and sensitivity. Levels of anti-Id Abs against two anti-Lol p I monoclonal antibodies (290A-167, 348A-6) were higher in normal volunteers than in untreated atopic patients. Specific immunotherapy increased the levels of anti-Id Abs to those of normal volunteers. These observations suggest a role for the Id-anti-Id network in the regulation of IgE antibody production.
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Affiliation(s)
- J Hébert
- Unité de Recherche Inflammation et Immunologie-Rhumatologie Centre Hospitalier de l'Université Laval, Québec City, Canada
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Abstract
Murine monoclonal antibodies (MAbs) against three non-overlapping epitopes of Lol p I allergen were previously produced and subsequently used for purification of the allergen. In the present study, these MAbs were further characterized, and the biological activity of the purified allergen assessed. The three MAbs were of the IgG isotype and carried a kappa light chain. Their affinity constants were in the range of 7.4-15.1 x 10(-9) mol/l. Purified Lol p I kept its biological activity, as shown by its ability to induce histamine release by basophils of Lol p I-sensitive patients. The profiles of histamine release induced by either Lol p I or crude Lolium perenne extracts were comparable. This observation suggests that human IgE bound to basophils are polyspecific which has been confirmed by immunoblot and inhibition assay. Our data indicated also that Lol p I possesses a major allergenic epitope recognized by all human serum IgE tested. This epitope seems to be partially shared by those recognized by the three MAbs. Finally, preincubation of Lol p I with either one of the Mabs did not affect significantly the basophil-histamine release induced by the purified allergen. This suggests that Lol p I possesses allergenic sites other than the one shared by MAbs and IgE Abs.
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Affiliation(s)
- W Mourad
- Unité de Recherche Inflammation et Immunologie-Rhumatologie, Ste-Foy, Canada
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35
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Sady SP, Cullinane EM, Saritelli A, Bernier D, Thompson PD. Elevated high-density lipoprotein cholesterol in endurance athletes is related to enhanced plasma triglyceride clearance. Metabolism 1988; 37:568-72. [PMID: 3374323 DOI: 10.1016/0026-0495(88)90173-4] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
We compared the clearance rate (K2) of plasma triglycerides (TG) following the intravenous (IV) infusion of a fat emulsion in 13 male endurance athletes (age 33 +/- 5.6 years, mean +/- SD) and 12 sedentary men (33 +/- 5.6 years). The athletes had lower fasting triglycerides (TG) (75 +/- 30.4 mg/dL v 125 +/- 52.5 mg/dL) and higher high-density lipoprotein (HDL) cholesterol concentrations (64 +/- 16.2 mg/dL v 42 +/- 9.4 mg/dL) than the sedentary subjects (P less than .01 for all). The higher HDL concentrations were due to increases in both the HDL2 and HDL3 subfractions. K2 in the athletes was 92% higher than that in the sedentary men (4.8 +/- 2.3%/min v 2.5 +/- 0.7%/min, P less than .01), but there was no difference in postheparin lipoprotein lipase activity (LPLA) between the groups (P greater than .05). K2 was positively correlated with LPLA (r = .51) and inversely related to fasting TG concentrations (r = -.73, P less than .01 for both). Furthermore, K2 was directly related to HDL (r = .75), HDL2 (r = .72), and HDL3 (r = .60) cholesterol concentrations (P less than .01 for all). These data suggest that the low TG levels in endurance athletes result at least in part from increased TG removal and that the elevated HDL concentrations of endurance athletes are related to enhanced fat clearance.
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Affiliation(s)
- S P Sady
- Division of Nutrition and Metabolism, Miriam Hospital, Providence, RI 02906
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36
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Guertin M, LaRue H, Bernier D, Wrange O, Chevrette M, Gingras MC, Bélanger L. Enhancer and promoter elements directing activation and glucocorticoid repression of the alpha 1-fetoprotein gene in hepatocytes. Mol Cell Biol 1988; 8:1398-407. [PMID: 2454390 PMCID: PMC363296 DOI: 10.1128/mcb.8.4.1398-1407.1988] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.1] [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: 01/01/2023] Open
Abstract
Mutations were introduced in 7 kilobases of 5'-flanking rat alpha 1-fetoprotein (AFP) genomic DNA, linked to the chloramphenicol acetyltransferase gene. AFP promoter activity and its repression by a glucocorticoid hormone were assessed by stable and transient expression assays. Stable transfection assays were more sensitive and accurate than transient expression assays in a Morris 7777 rat hepatoma recipient (Hepa7.6), selected for its strong AFP repression by dexamethasone. The segment of DNA encompassing a hepatocyte-constitutive chromatin DNase I-hypersensitive site at -3.7 kilobases and a liver developmental stage-specific site at -2.5 kilobases contains interacting enhancer elements sufficient for high AFP promoter activity in Hepa7.6 or HepG2 cells. Deletions and point mutations define an upstream promoter domain of AFP gene activation, operating with at least three distinct promoter-activating elements, PEI at -65 base pairs, PEII at -120 base pairs, and DE at -160 base pairs. PEI and PEII share homologies with albumin promoter sequences, PEII is a near-consensus nuclear factor I recognition sequence, and DE overlaps a glucocorticoid receptor recognition sequence. An element conferring glucocorticoid repression of AFP gene activity is located in the upstream AFP promoter domain. Receptor-binding assays indicate that this element is the glucocorticoid receptor recognition sequence which overlaps with promoter-activating element DE.
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Affiliation(s)
- M Guertin
- Le Centre de Recherche en Cancérologie de l'Université Laval, Québec, Canada
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37
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Piran U, Kohn DW, Uretsky LS, Bernier D, Barlow EH, Niswander CA, Stastny M. Immunochemiluminometric assay of creatine kinase MB with a monoclonal antibody to the MB isoenzyme. Clin Chem 1987. [DOI: 10.1093/clinchem/33.9.1517] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Abstract
Previous two-site immunometric assays for creatine kinase (CK; EC 2.7.3.2) MB isoenzyme have been based on formation of a "sandwich" complex involving CK-MB and antibodies that recognize the CK-MM and the CK-BB isoenzymes. Single-incubation model assays of CK-MB with these antibodies were susceptible to interferences by CK-MM and CK-BB. We produced two anti-CK-MB monoclonal antibodies and studied their suitability for two-site assays. Both antibodies were compatible with anti-CK-MM and anti-CK-BB, but not with each other. Using anti-CK-MB as the tracer antibody eliminated the interference by both CK-MM and CK-BB. Labeling anti-CK-MB with acridinium ester and immobilizing anti-CK-BB on paramagnetic particles, we developed a rapid and highly sensitive chemiluminescent/magnetic separation CK-MB assay. As little as 1 microgram of CK-MB per liter was detectable after 10- or 30-min incubation at room temperature, and the standard curve was linear up to 400 micrograms/L. Results for serum samples by the new assay correlated well (r = 0.94) with those by Corning electrophoretic and the Hybritech Tandem-E immunoenzymometric CK-MB methods. Sera containing macro CK-1 or high concentrations of CK-MM and CK-BB did not interfere. The combined advantages of a more-specific antibody, paramagnetic solid phase, and chemiluminescent label endow this two-site CK-MB assay with performance characteristics and ease of use superior to those of previous assays.
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Piran U, Kohn DW, Uretsky LS, Bernier D, Barlow EH, Niswander CA, Stastny M. Immunochemiluminometric assay of creatine kinase MB with a monoclonal antibody to the MB isoenzyme. Clin Chem 1987; 33:1517-20. [PMID: 3304711] [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: 01/05/2023]
Abstract
Previous two-site immunometric assays for creatine kinase (CK; EC 2.7.3.2) MB isoenzyme have been based on formation of a "sandwich" complex involving CK-MB and antibodies that recognize the CK-MM and the CK-BB isoenzymes. Single-incubation model assays of CK-MB with these antibodies were susceptible to interferences by CK-MM and CK-BB. We produced two anti-CK-MB monoclonal antibodies and studied their suitability for two-site assays. Both antibodies were compatible with anti-CK-MM and anti-CK-BB, but not with each other. Using anti-CK-MB as the tracer antibody eliminated the interference by both CK-MM and CK-BB. Labeling anti-CK-MB with acridinium ester and immobilizing anti-CK-BB on paramagnetic particles, we developed a rapid and highly sensitive chemiluminescent/magnetic separation CK-MB assay. As little as 1 microgram of CK-MB per liter was detectable after 10- or 30-min incubation at room temperature, and the standard curve was linear up to 400 micrograms/L. Results for serum samples by the new assay correlated well (r = 0.94) with those by Corning electrophoretic and the Hybritech Tandem-E immunoenzymometric CK-MB methods. Sera containing macro CK-1 or high concentrations of CK-MM and CK-BB did not interfere. The combined advantages of a more-specific antibody, paramagnetic solid phase, and chemiluminescent label endow this two-site CK-MB assay with performance characteristics and ease of use superior to those of previous assays.
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Cohen E, Bernier D, Tam S, Schimel D, Postel AH, Scheidt S, Stamm JB. Data quality and DRGs: an assessment of the reliability of federal beneficiary discharge data in selected Manhattan hospitals. J Community Health 1985; 10:238-46. [PMID: 3938456 DOI: 10.1007/bf01371017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
New York County Health Services Review Organization (NYCHSRO), the physicians' professional standards review organization of Manhattan, examined whether diagnostic coding errors identified in Manhattan hospitals would affect reimbursement under a diagnostic-related group (DRG) method of financing inpatient services. A sampling of 1,027 Medicare and Medicaid cases representing discharges from 18 Manhattan hospitals during 1982 and 1983 revealed incorrect DRG assignment for 17.5% of patient record abstracts, but these appear to have been unsystematic rather than deliberate errors. The difference between estimated reimbursement based on original and reabstracted records was not statistically significant either in the aggregate or for specific hospitals. It is emphasized that while New York State's Prospective Hospital Reimbursement Methodology (in effect during the study period) is not solely dependent upon DRG's case-mix is one of several factors used to make adjustments to existing per diem rates. A key recommendation is that hospitals conduct internal monitorings with all involved departments to improve the quality of the data abstracting process.
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Abstract
Thyroid-growth-blocking antibodies are present in large proportion of mothers who give birth to hypothyroid infants. In order to devise a prenatal screening test to replace the time-consuming cytobiochemical assay for measurement of the maternal antibodies, a cloned rat-thyroid cell-line (FRTL5) was used. Several approaches that had been tried previously had proved fruitless--eg, in FRTL5 cells immunoglobulin of mothers of affected infants did not displace 125I-labelled TSH from its receptor, did not block TSH-induced increase of cyclic AMP, and did not block TSH-induced 3H-thymidine incorporation. By use of 125I uptake by the cells, mothers of the hypothyroid children were readily distinguished from normal female subjects and normal pregnant women.
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Landry J, Bernier D, Ouellet C, Goyette R, Marceau N. Spheroidal aggregate culture of rat liver cells: histotypic reorganization, biomatrix deposition, and maintenance of functional activities. J Cell Biol 1985; 101:914-23. [PMID: 2411740 PMCID: PMC2113699 DOI: 10.1083/jcb.101.3.914] [Citation(s) in RCA: 424] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Liver cells isolated from newborn rats and seeded on a non-adherent plastic substratum were found to spontaneously re-aggregate and to form, within a few days, spheroidal aggregates that eventually reached a plateaued diameter of 150-175 micron. Analyses on frozen sections from these spheroids by immunofluorescence microscopy using antibodies to various cytoskeletal elements and extracellular matrix components revealed a sorting out and a histotypic reorganization of three major cell types. A first type consisted of cells that segregated out on the aggregate surface forming a monolayer cell lining; a second type was identified as hepatocytes that regrouped in small islands often defining a central lumen; and a third group of cells reorganized into bile duct-like structures. This intercellular organization in the aggregates was paralleled by the accumulation of extracellular matrix components (laminin, fibronectin, and collagen) and their deposition following a specific pattern around each cell population structure. Determinations of albumin secretion and tyrosine aminotransferase induction by dexamethasone and glucagon at various times after the initiation of the cultures revealed a maintenance of the hepatocyte-differentiated functions for at least up to 2 mo at the levels measured at 3-5 d. It is concluded that cells dispersed as single cells from newborn rat liver conserve in part the necessary information to reconstruct a proper three-dimensional cyto-architecture and that the microenvironment so generated most likely represents a basic requirement for the optimal functioning of these differentiated cells.
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Kantor MA, Bianchini A, Bernier D, Sady SP, Thompson PD. Androgens reduce HDL2-cholesterol and increase hepatic triglyceride lipase activity. Med Sci Sports Exerc 1985; 17:462-5. [PMID: 4033402 DOI: 10.1249/00005768-198508000-00010] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
We quantified serum lipids and postheparin plasma lipolytic activities in 5 weightlifters presently self-administering androgenic steroids (users) and an equal number not currently using these drugs (non-users). Mean (+/- SD) age (23 +/- 2 vs 25 +/- 4 yr), body weight (102.7 +/- 11.4 vs 86.8 +/- 13.6 kg), and percent body fat (8.6 +/- 2.5 vs 7.8 +/- 6.0%) were not different in users and non-users, respectively. Similarly, there were no differences in total cholesterol (183 +/- 27 vs 176 +/- 32 mg.dl-1) low-density lipoprotein-cholesterol (138 +/- 25 vs 108 +/- 32 mg.dl-1), or triglyceride (93 +/- 26 vs 93 +/- 41 mg.dl-1) levels in the two groups. High-density lipoprotein (HDL)-cholesterol concentrations, however, were significantly lower in the users (26 +/- 10 vs 50 +/- 13 mg.dl-1; P less than 0.05), and most of the difference was due to lower HDL2-cholesterol concentrations (6 +/- 4 vs 22 +/- 9 mg.dl-1; P less than 0.05). Postheparin plasma lipoprotein lipase activity was only slightly lower in the users (3.49 +/- 2.23 vs 5.36 +/- 1.73 mumol FFA.ml-hr-1; P= NS). but hepatic triglyceride lipase activity was significantly higher in this group (27.99 +/- 6.89 vs 11.15 +/- 2.76, mumol FFA.ml-hr-1: P less than 0.001) and correlated inversely with HDL2-cholesterol concentrations (r = -0.81; P less than 0.01). We conclude that androgenic hormones reduce HDL-cholesterol concentrations and the HDL2-cholesterol subfraction, possibly by enhancing hepatic triglyceride lipase activity.
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Abstract
Abstract
A quantitative assay based on endpoint immunonephelometry was developed for human apolipoprotein A-II (apoA-II) in plasma or serum. Dilution of plasma samples with a 0.1 mol/L solution of sodium cholate enhanced the quantification. We used either purified apoA-II as the primary standard or plasma as a secondary standard. Results correlated well (r = 0.90) with those by a double-antibody radioimmunoassay for 63 serum samples from both normal and hyperlipemic individuals. The interassay coefficient of variation for the immunonephelometric assay was 7% within a working range between 0.05 and 0.7 microgram of apoA-II per sample (corresponding to a 1500-fold final dilution of serum). No extraction of samples with organic solvent is necessary if the triglyceride concentration is less than 4 g/L.
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Rosseneu M, Vinaimont N, Musliner TA, Bernier D, Herbert PN, Belpaire F. Immunonephelometry of apolipoprotein A-II in plasma. Clin Chem 1984; 30:234-7. [PMID: 6420089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
A quantitative assay based on endpoint immunonephelometry was developed for human apolipoprotein A-II (apoA-II) in plasma or serum. Dilution of plasma samples with a 0.1 mol/L solution of sodium cholate enhanced the quantification. We used either purified apoA-II as the primary standard or plasma as a secondary standard. Results correlated well (r = 0.90) with those by a double-antibody radioimmunoassay for 63 serum samples from both normal and hyperlipemic individuals. The interassay coefficient of variation for the immunonephelometric assay was 7% within a working range between 0.05 and 0.7 microgram of apoA-II per sample (corresponding to a 1500-fold final dilution of serum). No extraction of samples with organic solvent is necessary if the triglyceride concentration is less than 4 g/L.
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Landry J, Bernier D, Chrétien P, Nicole LM, Tanguay RM, Marceau N. Synthesis and degradation of heat shock proteins during development and decay of thermotolerance. Cancer Res 1982; 42:2457-61. [PMID: 7074623] [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: 01/23/2023]
Abstract
Morris hepatoma 7777 cells, heat conditioned at 43 degrees for 0.5 hr, become gradually thermoresistant during an incubation at 37 degrees as judged by their ability to form colonies following a second heat challenge. Pulse incorporation of [35S]methionine into proteins at various times after the conditioning treatment and subsequent fractionation of the proteins by polyacrylamide gel electrophoresis indicate that the gradual putative modifications occurring at the cellular level and leading to the thermotolerance state are accompanied by an elevated synthesis above the normal level of a small set of polypeptides with apparent molecular weights of 27,000, 65,000, 68,000, 70,000, 89,000, and 107,000. Both thermotolerance development and protein induction are completed after a 6- to 8-hr period. At the end of this period, thermotolerance is at its maximum level and heat shock protein synthesis is returned to normal. This acquired thermal resistance eventually disappears between 60 and 80 hr following conditioning treatment. In a parallel manner, the heat shock-induced proteins synthesized during the first 4 hr following the conditioning treatment are maintained in the cells at a high level for several hr but become undetectable by 82 hr. The results provide strong circumstantial evidence that heat shock proteins are involved in the acquisition, maintenance, and decay of thermotolerance.
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Bernier D, Gaston L. [Anti-stress intervention with a health and social service clientele.]. Sante Ment Que 1982; 7:28-36. [PMID: 17093744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
The present study concerns an anti-stress intervention involving a social and health services clientele. This category of the population represents the individuals who are statistically the most affected by stress. The anti-stress intervention used consists in assisting the individual to work towards the modification of his "stressors" and to permit him to reduce psycho-physiological tension as a result of the practice of progressive relaxation. Results demonstrate that a portion of this clientele is effectively more anxious than the mean of the population and that the intervention permits a significant reduction of situational anxiety as measured by the STAI.
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Landry J, Chrétien P, Bernier D, Nicole LM, Marceau N, Tanguay RM. Thermotolerance and heat shock proteins induced by hyperthermia in rat liver cells. Int J Radiat Oncol Biol Phys 1982; 8:59-62. [PMID: 7061256 DOI: 10.1016/0360-3016(82)90385-6] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Hepatic epithelial cells become thermotolerant when conditioned with a 30 minute heat-treatment at 43 degrees C. The effect reaches a full amplitude after a 4-8 hour period at 37 degrees C and lasts for more than one day at a level corresponding to a 50-fold increase in cellular thermoresistance. During the development period, electrophoretic patterns of proteins from cells incubated in presence of 35S-methionine reveal an increased synthesis of a small set of proteins with molecular weights of 107, 89, 70, 68 and 27KD. The maximal synthesis of the induced proteins occurs concomitantly with the maximal increase of cell thermotolerance and has returned to normal when thermotolerance levels off. The induction of specific protein synthesis is also observed in other liver epithelial cells of normal and cancerous origins and in freshly isolated hepatocytes. It is suggested that the accumulation of these proteins in the cells plays a role in the process leading to a thermotolerant state.
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