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Malik J, Kaufmann G, Hirsiger P, Kümmerlen D, Arnold C, Spring P, Sidler X. Influence of personal attitude of the manager on antibiotic use in pig production. SCHWEIZ ARCH TIERH 2015; 157:675-81. [DOI: 10.17236/sat00045] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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2
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Affiliation(s)
- A. Müller
- Anorganisch-Chemisches Institut der Universität Göttingen
| | - R. Kebabcioglu
- Anorganisch-Chemisches Institut der Universität Göttingen
| | - M. J. F. Leroy
- Laboratoire de Chimie Minérale, Faculté de Sciences de Strasbourg
| | - G. Kaufmann
- Laboratoire de Chimie Minérale, Faculté de Sciences de Strasbourg
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Voigt JP, Kaufmann G, Hirsch B, Leonhardt S, Jarry H, Oehme P, Wuttke W. In vivo-effect of intraadrenal nicotine and substance P application on rat adrenal medullary catecholamine secretion. Exp Clin Endocrinol 2009; 102:111-7. [PMID: 7520004 DOI: 10.1055/s-0029-1211272] [Citation(s) in RCA: 5] [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] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The present study was conducted to characterize in vivo the intraadrenal catecholamine (CA) secretion in rats. This was possible by using a microdialysis system (MDS) which mimics some properties of an artificial capillary. One end of this system was connected to a peristaltic pump, from the other end fractions were sampled at 5 min intervals. Concentrations of epinephrine (E) and norepinephrine (NE) in adrenal dialysate fractions were determined by HPLC electrochemical detection. Through this MDS nicotine was administered directly into the adrenal medulla of freely moving rats and the response of catecholamine release was determined. In the second part of the study the effect of exogenous substance P (SP) on spontaneous as well as on nicotine-stimulated CA release was investigated. Like nicotine, SP was administered directly into the adrenal medulla. At a flow rate of 25 microliter/min the transfer rates of CA and nicotine were approximately 1% whereas SP passed at a rate of 01.-0.2%. Under resting conditions CA release remained constant. In response to 2 x 10(-7) M nicotine (which resulted in local concentration of 2 x 10(-7) M), E and NE secretion increased 2.9 and 5.4-fold, respectively. However, due to an increased E response this difference attenuated with a later onset of the first stimulus. The higher concentrations of 10(-4) M resulted in 8.1 and 10.8-fold increases for E and NE. This latter response is clearly supraphysiologic and therefore the 2 x 10(-5) M concentration was used for further experimentation. CA secretion was stimulated with nicotine four times at 30 min intervals.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- J P Voigt
- University of Göttingen, Department of Obstetrics and Gynecology, Germany
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6
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Oettel M, Breitbarth H, Elger W, Gräser T, Hübler D, Kaufmann G, Moore C, Patchev V, Römer W, Schröder J, Sobek L, Zimmermann H. The pharmacological profile of dienogest. EUR J CONTRACEP REPR 2009. [DOI: 10.3109/13625189909085259] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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8
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Kaufmann G, Wanner J, Amsler H. Tuberkelbazillen in resezierten Lungenherden. Respiration 2009. [DOI: 10.1159/000191597] [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: 11/19/2022] Open
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9
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Nager F, Kaufmann G, Schaub F. Die Leistungsfähigkeit mechanokardiographischer Untersuchungen in der Erfassung der Mitralinsuffizienz und ihres Schweregrades unter besonderer Berücksichtigung der kombinierten Mitralvitien. Cardiology 2008. [DOI: 10.1159/000167905] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Scheu H, Rutishauser W, Kaufmann G, Lüthy E. Rechts-links Shunt bei unkompliziertem Vorhofseptumdefekt. Cardiology 2008. [DOI: 10.1159/000167712] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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13
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Lüthy E, Rutishauser W, Scheu H, Kaufmann G. Das enddiastolische Volumen und seine haemodynamischen Korrelationen beini suffizienten linken Ventrikel. Cardiology 2008. [DOI: 10.1159/000167710] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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14
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17
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Ehrhard S, Wernli M, Kaufmann G, Pantaleo G, Rizzardi GP, Gudat F, Erb P, Battegay M. Effect of antiretroviral therapy on apoptosis markers and morphology in peripheral lymph nodes of HIV-infected individuals. Infection 2008; 36:120-9. [PMID: 18379725 DOI: 10.1007/s15010-008-7368-9] [Citation(s) in RCA: 11] [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] [Received: 09/20/2007] [Accepted: 12/04/2007] [Indexed: 11/30/2022]
Abstract
BACKGROUND CD4+ T cell depletion and destruction and the involution of the lymphoid tissue are hallmarks of HIV infection. Although the underlying mechanisms are still unclear, apoptosis appears to play a central role. The objective of this study was to investigate the effect of antiretroviral therapy on the lymph node tissue, particularly with respect to morphology and apoptosis. PATIENTS AND METHODS Between 1997 and 1999, two inguinal lymph nodes were excised from 31 previously untreated individuals who were in an early stage of HIV infection, the first one prior to treatment and the second after 16 to 20 months of treatment. Paraffin sections were investigated for lymph node architecture, distribution of cellular and viral markers, apoptosis, and expression of apoptotic key molecules which indirectly reflect apoptotic processes. RESULTS After 16-20 months of antiretroviral therapy, a significant decrease in highly activated HIV-driven immune response was observed in the lymph node tissue as a marked reduction in follicular hyperplasia, a normalization of the follicular dendritic cell network, a significant increase in the number of CD4+ T cells, and a significant decrease in the number of CD8+ T cells. The expression of several proapoptotic (Fas, TRAIL, and active caspase 3) and antiapoptotic (Bcl-2 and IL-7Ralpha) molecules that were reconstituted in the tissues during therapy resembled their expression in lymph nodes of HIV-negative individuals. Limitations of the study are (a) the lack of untreated patients in the late stages, (b) for ethical reasons, the lack of a control group with untreated patients, and (c) for methodological reasons, the restriction of sequential measurements of apotpotic markers to one-third of the patients. CONCLUSION Antiretroviral therapy initiated in the early stages in HIV infection may halt the irreversible destruction of the lymph node tissue and may partially normalize apoptotic processes.
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Affiliation(s)
- S Ehrhard
- Institute for Medical Microbiology, University of Basel, Basel, Switzerland
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18
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Elzi L, Kaufmann G, Weber R, Hirschel B, Cavassini M, Furrer H, Bernasconi E, Vernazza P, Klimkait T, Rickenbach M, Battegay M. 71 Discontinuation of enfuvirtide after long-term administration in HIV-1-infected patients: the Swiss HIV cohort study (SHCS). Int J Infect Dis 2006. [DOI: 10.1016/s1201-9712(06)80068-8] [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: 10/24/2022] Open
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19
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Görlitzer K, Bonnekessel C, Jones PG, Kaufmann G. [Unexpected formation of an estrone derivative from androsta-1,4-diene-3,17-dione]. Pharmazie 2002; 57:808-10. [PMID: 12561240] [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: 02/28/2023]
Abstract
Reaction of androsta-1,4-diene-3,17-dione (1) with pyrrolidine and p-toluenesulfonic acid in toluene gives 3-pyrrolidino-estra-1,3,5(10)-triene-6,17-dione (7) in poor yield, whose structure is shown by X-ray analysis. Compared with 3H-estradiol, compound 7 shows only a weak receptor binding activity tested in an in vitro screening using rabbit uterus cytosol.
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Affiliation(s)
- K Görlitzer
- Institut für Pharmazeutische Chemie, Technischen Universität Braunschweig, Germany.
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20
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Kaufmann G. State v. Chabot: a euthanasia case from the Netherlands. Ohio North Univ Law Rev 2002; 20:815-20. [PMID: 12199252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
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21
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Choplin F, Marc R, Kaufmann G, Wipke WT. Computer Design of Synthesis in Phosphorus Chemistry: Automatic Treatment of Stereochemistry. ACTA ACUST UNITED AC 2002. [DOI: 10.1021/ci60014a016] [Citation(s) in RCA: 9] [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: 11/28/2022]
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22
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Schwarz S, Thieme I, Kosemund D, Undeutsch B, Kummer M, Görls H, Römer W, Kaufmann G, Elger W, Hillisch A, Schneider B. Studies on modified estrogens: towards the synthesis of novel 14,15-cyclopropa[a]estra-1,3,5(10),8-tetraenes. Pharmazie 2001; 56:843-9. [PMID: 11817166] [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: 02/23/2023]
Abstract
To improve the ratio of non-hormonal to hormonal activity, estrogens 3 and 4 were modified at various molecule positions. Isomerization of the 14 alpha,15 alpha-methylene bridge, controlled 3-methoxy group cleavage with respect to the 14 alpha,15 alpha-methylene bridge stereochemistry, reduction of the 8-double bond, and substitution of the oxyfunctionality at C-17 by a methylene and a difluoromethylene moiety were in the focus. As a result of in vivo and in vitro tests, compounds 27 and 29 were selected as potential follow-up candidates of lead 3.
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Affiliation(s)
- S Schwarz
- Division of Research and Development, Jenapharm GmbH & Co. KG, Jena, Germany.
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23
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Kaufmann G. [Not Available]. Zur Medizingesch Abh 2001; 263:1-52. [PMID: 11625874] [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: 02/21/2023]
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24
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Mass G, Nethanel T, Lavrik OI, Wold MS, Kaufmann G. Replication protein A modulates its interface with the primed DNA template during RNA-DNA primer elongation in replicating SV40 chromosomes. Nucleic Acids Res 2001; 29:3892-9. [PMID: 11557822 PMCID: PMC55912 DOI: 10.1093/nar/29.18.3892] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The eukaryal single-stranded DNA binding protein replication protein A (RPA) binds short oligonucleotides with high affinity but exhibits low cooperativity in binding longer templates, opposite to prokaryal counterparts. This discrepancy could reflect the smaller size of the replicative template portion availed to RPA. According to current models, this portion accommodates an RNA-DNA primer (RDP) of <40 nt (nested discontinuity) or a several-fold longer Okazaki fragment (initiation zone). Previous in situ UV-crosslinking revealed that RPA also interacts with nascent DNA, especially growing RDPs. Here we compare nascent SV40 DNA chains UV-crosslinked to the middle and large RPA subunits and use the data to re-examine the two models. The middle subunit interacted with the nascent chains after a few DNA residues were added to the RNA primer while the large subunit became accessible after extension by several more. Upon RDP maturation, the middle subunit disengaged while the large subunit remained accessible during further limited extension. A corresponding shift in preference in favor of the large subunit has been reported for purified RPA and synthetic gapped duplexes upon reduction of the gap from 19 to 9 nt. Combined, these facts support the proposal that the mature RDP faces downstream a correspondingly small gap, possibly created by removal of the RNA primer moiety from an adjacent, previously synthesized RDP (nested discontinuity) but insufficient for continuous elongation of the RDP into an Okazaki fragment (initiation zone).
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Affiliation(s)
- G Mass
- Department of Biochemistry, Tel Aviv University, Ramat Aviv, 69978 Israel
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25
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Kähler CM, Pischel AB, Haller T, Meierhofer C, Djanani A, Kaufmann G, Wiedermann CJ. Signal transduction pathways in directed migration of human monocytes induced by human growth hormone in vitro. Int Immunopharmacol 2001; 1:1351-61. [PMID: 11460315 DOI: 10.1016/s1567-5769(01)00067-4] [Citation(s) in RCA: 10] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The human growth hormone (GH) was shown to modulate leukocyte functions such as stimulating directed migration of human monocytes in vitro. Dimerisation of GH-receptors leads to the activation of various signalling mechanisms. As transduction of GH signals to monocytes is unknown, we investigated GH signalling mechanisms in monocyte migration using a modified Boyden chamber chemotaxis assay. Inhibition of tyrosyl phosphorylation of GH receptor-associated tyrosine kinase by tyrphostin-23 or staurosporine blocked GH-stimulated monocyte migration down to random levels. Furthermore, pre-incubation with effective concentrations of 4B-phorbol-12-myristate-13-acetate (PMA), staurosporine and bisindolylmaleimide I, inhibitors of protein kinase C, significantly decreased GH-induced migration, suggesting that PKC is involved in the signalling cascade. Additionally, phosphatidylinositol 3-kinase and mitogen-activated protein kinase (MAPK) activation seems to be required. This study revealed signalling pathways in monocyte movement toward GH in vitro.
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Affiliation(s)
- C M Kähler
- Pneumology Service, Department of General Internal Medicine, Faculty of Medicine, University of Innsbruck, Anichstrasse, 35, 6020 Innsbruck, Austria
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26
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Abstract
The bacterial tRNA(Lys)-specific PrrC-anticodon nuclease cleaves its natural substrate 5' to the wobble base, yielding 2',3'-cyclic phosphate termini. Previous work has implicated the anticodon of tRNA(Lys) as a specificity element and a cluster of amino acid residues at the carboxy-proximal half of PrrC in its recognition. We further examined these assumptions by assaying unmodified and hypomodified derivatives of tRNA(Lys) as substrates of wild-type and mutant alleles of PrrC. The data show, first, that the anticodon sequence and wobble base modifications of tRNA(Lys) play major roles in the interaction with anticodon nuclease. Secondly, a specific contact between the substrate recognition site of PrrC and the tRNA(Lys) wobble base is revealed by PrrC missense mutations that suppress the inhibitory effects of wobble base modification mutations. Thirdly, the data distinguish between the anticodon recognition mechanisms of PrrC and lysyl-tRNA synthetase.
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MESH Headings
- Alleles
- Amino Acid Sequence
- Anticodon/genetics
- Anticodon/metabolism
- Bacterial Proteins/chemistry
- Bacterial Proteins/genetics
- Bacterial Proteins/metabolism
- Base Sequence
- Binding Sites
- Escherichia coli/enzymology
- Escherichia coli/genetics
- Escherichia coli/growth & development
- Escherichia coli Proteins
- Genes, Bacterial/genetics
- Genes, Bacterial/physiology
- Lysine-tRNA Ligase/metabolism
- Molecular Sequence Data
- Mutation, Missense/genetics
- Point Mutation/genetics
- Protein Structure, Secondary
- RNA, Bacterial/genetics
- RNA, Bacterial/metabolism
- RNA, Transfer, Lys/genetics
- RNA, Transfer, Lys/metabolism
- Ribonucleases/chemistry
- Ribonucleases/genetics
- Ribonucleases/metabolism
- Substrate Specificity
- Suppression, Genetic/genetics
- tRNA Methyltransferases/genetics
- tRNA Methyltransferases/metabolism
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Affiliation(s)
- Y Jiang
- Department of Biochemistry, Tel Aviv University, Ramat Aviv 69978, Israel
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27
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Kähler CM, Pischel A, Kaufmann G, Wiedermann CJ. Influence of neuropeptides on neutrophil adhesion and transmigration through a lung fibroblast barrier in vitro. Exp Lung Res 2001; 27:25-46. [PMID: 11202062 DOI: 10.1080/019021401459752] [Citation(s) in RCA: 12] [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: 10/16/2022]
Abstract
The lung is richly supplied with peptidergic nerves that store and secrete substance P (SP), vasoactive intestinal peptide (VIP), and other neuropeptides known to potently modulate leukocyte function in vitro and airway inflammation in vivo. We examined the effect of SP, VIP and the novel sensory neuropeptide secretoneurin (SN), as well as of interleukin (IL)-8, IL-6, IL-1 beta, transforming growth factor (TGF)-beta, and tumor necrosis factor (TNF), all associated with acute lung injury, on human neutrophil migration across a 5-mu pore polycarbonate filter system covered by human lung fibroblast monolayers. Additionally, we tested the ability of these neuropeptides to elicit neutrophil adhesion to fibroblast monolayers. SP, but not VIP and SN, may be important in directly influencing neutrophil adhesion to and subsequent migration across a subendothelial barrier of fibroblasts and extracellular matrix towards lung inflammatory sites. The effect was mainly mediated by neurokinin (NK)-1 receptors, as evaluated by a specific NK-1 antagonist, [[(S,S)Pro-Leu(spiro-y-lactam)]9,10, Trp11]substance P (1-11), whereas a specific NK-2 receptor antagonist, [Tyr5, D-Trp6,8,9, Lys10]neurokinin A (4-10), was ineffective. The SP analog septide and the NK-1 receptor agonist ([Sar9 Met(O2)11)SP were comparably effective. Furthermore, the SP effect was concentration and time dependent. However, the other tested neuropeptides might also affect neutrophil recruitment in inflammatory lung by modulating other lung cell functions. Additionally, all tested cytokines stimulated neutrophil transfibroblast migration in vitro, except IL-6. In conclusion, SP in concert with proinflammatory cytokines may regulate neutrophil interstitial accumulation and their traffic to the alveolar space in lung inflammation.
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Affiliation(s)
- C M Kähler
- Department of Internal Medicine, Division of General Internal Medicine-Pulmonology and ICU, Faculty of Medicine, University of Innsbruck, Innsbruck, Austria.
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28
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Elger W, Bartley J, Schneider B, Kaufmann G, Schubert G, Chwalisz K. Endocrine pharmacological characterization of progesterone antagonists and progesterone receptor modulators with respect to PR-agonistic and antagonistic activity. Steroids 2000; 65:713-23. [PMID: 11108882 DOI: 10.1016/s0039-128x(00)00178-1] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.6] [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] [Indexed: 11/18/2022]
Abstract
Studies were conducted to assess progesterone antagonists (PAs) and progesterone receptor modulators (PRMs) with respect to PR agonistic and antagonistic activities in vivo. These properties are not always adequately reflected in transactivation in vitro models. Studies were performed in pregnant rats, estrogen-primed rabbits (McPhail -Test), and cycling and pregnant guinea pigs. Tested compounds included mifepristone (RU486), onapristone, J867, J956, J1042, and ZK137316. J-compounds induced sub-maximum endometrial transformation and, paradoxically, inhibited effects of progesterone in rabbits. Mifepristone, onapristone, and ZK137316 behaved as 'pure' antagonists in this species. Inhibition of uterine PGF(2alpha) secretion and inhibition of luteolysis in cycling guinea pigs were more sensitive parameters of PR-agonistic and antagonistic properties. 'Pure' PAs inhibited uterine PGF(2alpha) secretion and luteal regression completely. The PR agonist R5020 reversed both effects which demonstrates a PR mediation. Agonistic PRMs (J-substances and mifepristone) showed no or blunted antiluteolytic effects compared to the 'pure' PR antagonist onapristone. When tested in pregnant guinea pigs for their labor-inducing potential, PR agonistic PRMs had much reduced or abolished abortifacient activity compared to mifepristone (mifepristone > J956 > J867/J912 > J1042). However, in cycling animals, superior antiovulatory and antiproliferative properties of the J-substances were seen. Antiovulatory effects of 'pure' and agonistic PRMs are probably due to different mechanisms. The relevance of rodent studies for antiovulatory and uterine antiproliferative effects for the human is still uncertain. The non-abortifacient PRM J1042 induced stromal compaction and inhibition of endometrial proliferation in monkeys, but this effect was not stronger than that of the 'purer' PAs. 'Pure' PAs are important pharmacological tools analogous to PRKO models to study the role of PR in the menstrual cycle and in pregnancy.
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Affiliation(s)
- W Elger
- EnTec GmbH Labor Jena, Adolf Reichweinstrabetae 20, 07745, Jena, Germany.
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29
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Abstract
Carboxymethyl cellulose (CMC) powder formulation of apomorphine was prepared by lyophilization and characterized with respect to the in vitro and intranasal in vivo release of apomorphine in rabbits. This was compared to apomorphine release from degradable starch microspheres (DSM) and lactose, as well as in vivo absorption after subcutaneous injection. In vitro apomorphine release from CMC was sustained, unlike that of DSM and lactose. Changing the drug loading of CMC from 15 to 30% (w/w) influenced drug release rate, which increased with increased drug loading. In vivo absorption of apomorphine from lactose, DSM and subcutaneous injection were rapid and not sustained. Slower absorption rates of apomorphine occurred from CMC. The fastest absorption rate was obtained with lactose and the slowest with CMC of 15% (w/w) drug loading. The T(max) from the CMC dosage forms were significantly prolonged compared to the immediate release forms. Plasma drug levels were sustained with CMC. The plasma concentration was maintained within 50% of the C(max), longer (15% (w/w), 70 min; 30% (w/w), 40 min) compared to the rest (lactose, 20 min; DSM, 25 min, subcutaneous injection, 35 min). The sustained plasma level of apomorphine by CMC was achieved with relative bioavailabilities equivalent to subcutaneous injection.
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Affiliation(s)
- M Ikechukwu Ugwoke
- Laboratorium voor Farmacotechnologie en Biofarmacie, Campus Gasthuisberg O&N, Katholieke Universiteit Leuven, B-3000, Leuven, Belgium
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30
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31
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Abstract
A tRNALys-specific anticodon nuclease is kept in a latent form in a rare Escherichia coli strain, complexed with a DNA restriction enzyme. A phage T4 inhibitor of DNA restriction activates anticodon nuclease, but other T4 proteins restore tRNALys. Detection of a homologous system in Neisseria and a different anticodon nuclease in colicin E5 suggest ubiquity and diversity of such tRNA toxins. Analysis of these systems could reveal novel RNA recognition and cleavage mechanisms.
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Affiliation(s)
- G Kaufmann
- Dept of Biochemistry, Tel Aviv University, Ramat Aviv 69978, Israel.
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32
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Kaufmann G, Dautzenberg H, Henkel H, Müller G, Schäfer T, Undeutsch B, Oettel M. Nitrile hydratase from Rhodococcus erythropolis: metabolization of steroidal compounds with a nitrile group. Steroids 1999; 64:535-40. [PMID: 10493599 DOI: 10.1016/s0039-128x(99)00028-8] [Citation(s) in RCA: 10] [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] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The progestin dienogest (17alpha-cyanomethyl-17beta-hydroxy-estra-4,9-dien-3-one) was metabolized by the nitrile hydratase-containing microorganism Rhodococcus erythropolis. An enzymatic hydrolysis of the nitrile group at the 17alpha-side chain was intended to obtain novel derivatives and to test them for progesterone receptor affinity. In contrast to the rapid enzymatic hydrolysis of nonsteroidal nitriles, the nitrile group of dienogest was cleaved very slowly. The dominant reaction was an aromatization of ring A. After prolonged fermentation, the 17alpha-acetamido derivatives of estradiol and of 9(11)-dehydroestradiol were formed. Three of the metabolites were also prepared synthetically. They were tested for hormonal activity by assessing their binding to progesterone and estrogen receptors in vitro. Neither the aromatized 17alpha-acetamido derivatives nor the dienogest derivative 17alpha-acetamido-17beta-hydroxy-estra-4,9-dien-3-one, which was prepared synthetically only, exhibited affinity for the progesterone receptor.
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Affiliation(s)
- G Kaufmann
- Division of Research and Development, Jenapharm GmbH & Co. KG, Jena, Germany
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33
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Abstract
The tRNALys-specific anticodon nuclease exists in latent form in Escherichia coli strains containing the optional prr locus. The latency is a result of a masking interaction between the anticodon nuclease core-polypeptide PrrC and the Type IC DNA restriction-modification enzyme EcoprrI. Activation of the latent enzyme by phage T4-infection elicits cleavage of tRNALys 5' to the wobble base, yielding 5'-OH and 2', 3'-cyclic phosphate termini. The N-proximal half of PrrC has been implicated with (A/G) TPase and EcoprrI interfacing activities. Therefore, residues involved in recognition and cleavage of tRNALys were searched for at the C-half. Random mutagenesis of the low-G+C portion encoding PrrC residues 200-313 was performed, followed by selection for loss of anticodon nuclease-dependent lethality and production of full-sized PrrC-like protein. This process yielded a cluster of missense mutations mapping to a region highly conserved between PrrC and two putative Neisseria meningitidis MC58 homologues. This cluster included two adjacent members that relaxed the inherent enzyme's cleavage specificity. We also describe another mode of relaxed specificity, due to mere overexpression of PrrC. This mode was shared by wild-type PrrC and the other mutant alleles. The additional substrates recognised under the promiscuous conditions had, in general, anticodons resembling that of tRNALys. Taken together, the data suggest that the anticodon of tRNALys harbours anticodon nuclease identity elements and implicates a conserved region in PrrC in their recognition.
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Affiliation(s)
- R Meidler
- Department of Biochemistry, Tel Aviv University, Ramat Aviv, 69978, Israel
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34
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Rudakoff B, Undisz K, Mayer G, Sobek L, Kaufmann G, Thiericke R, Grabley S, Munder T. Dual reporter systems in yeast and mammalian cells for assessing progesterone receptor modulators. J Cell Biochem 1999; 73:126-36. [PMID: 10088731] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
In the present study we describe the set-up of a new one-hybrid reporter gene assay in Saccharomyces cerevisiae composed of the human progesterone receptor fused to the DNA-binding domain of the yeast transcriptional activator Gal4. This assay allows the convenient estimation of receptor mediated progestogenic as well as antiprogestogenic actions of compounds. The induction of the beta-galactosidase reporter gene expression correlated well with the progesterone receptor affinity and the concentration of the progestins tested. The results corresponded to those obtained from a reporter gene assay in the cancer cell line CV-1 and in vitro binding experiments using rabbit uterus cytosol. In both the yeast and CV-1 cells the activity of antiprogestins was detectable by inhibition of the progestin-induced reporter gene expression. Secondary reporter genes under the transcriptional control of receptor unrelated promoters have been introduced into yeast and mammalian test strains to distinguish between specific receptor mediated antihormone actions and nonspecific effects on cellular metabolism.
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Affiliation(s)
- B Rudakoff
- Hans-Knöll-Institut für Naturstoff-Forschung e.V., Jena, Germany
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35
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Kähler CM, Kaufmann G, Hogue-Angeletti R, Fischer-Colbrie R, Dunzendorfer S, Reinisch N, Wiedermann CJ. A soluble gradient of the neuropeptide secretoneurin promotes the transendothelial migration of monocytes in vitro. Eur J Pharmacol 1999; 365:65-75. [PMID: 9988125 DOI: 10.1016/s0014-2999(98)00814-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [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: 11/21/2022]
Abstract
Secretoneurin, derived from the chromogranin secretogranin II, triggers the selective migration of human monocytes, eosinophils, fibroblasts, endothelial and smooth muscle cells. More recently, we located specific binding sites on the human monocytic cell line MonoMac-6. Differentiated U937 transendothelial diapedesis was evaluated using an in vitro model of the vascular wall and specific monoclonal antibodies against CD11/CD18 and the alpha-chains of the very late activation antigen (VLA)-4 were used to evaluate involved adhesion molecules. Results showed a significant migratory response to secretoneurin between 10(-8) to 10(-10) M. Migration was comparable to a maximal effect induced by the monocyte chemotactic agent N-formyl-Met-Leu-Phe (fMLP, 10(-8) M). Rabbit anti-secretoneurin antibodies were able to block the neuropeptide effect but not of fMLP and a trypsinized secretoneurin preparation as well as the secretogranin II-fragment EL-17 were ineffective in eliciting migration. Transmigration of U937 across endothelial-layers toward secretoneurin is inhibited by antibodies to CD11/CD18 adhesion molecules. The novel neuropeptide secretoneurin may play a role in regulating migration of monocytes into the subendothelial space, supposing a role in inflammatory responses.
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Affiliation(s)
- C M Kähler
- Department of Internal Medicine, Faculty of Medicine, University of Innsbruck, Austria
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36
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Abstract
We construct a model based on biological principles of the interaction of HIV-1 with the CD4+ T cells at primary infection. Most of the parameters are obtained from the literature, the remainder from fitting the output of the model to data from seven patients. On the basis of the model we find that initial viral containment is due to an effective immune response. The viral level after the initial peak, a surrogate marker of disease progression, was determined by the rate of reactivation of memory cells. Differences in this rate may occur because of inter- or intra-individual differences in the capability of memory cells to recognise and dispose of variants of HIV, either due to immune escape mutations within the virus or because the virus directly inhibits reactivation. With no choice of parameters could direct and indirect killing produce the gradual loss in CD4+ T cells with the observed viral behaviour. The loss of CD4+ T cells is perhaps due to defective expansion of activated cells of both HIV specific and nonspecific cells. As less memory cells are produced as a result then this compartment decreases and hence so do naive numbers through less reversion of memory cells to the naive phenotype.
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Affiliation(s)
- J M Murray
- School of Mathematics, University of New South Wales, Sydney, Australia.
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37
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Mass G, Nethanel T, Kaufmann G. The middle subunit of replication protein A contacts growing RNA-DNA primers in replicating simian virus 40 chromosomes. Mol Cell Biol 1998; 18:6399-407. [PMID: 9774655 PMCID: PMC109225 DOI: 10.1128/mcb.18.11.6399] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.4] [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: 11/20/2022] Open
Abstract
The eukaryotic single-stranded DNA binding protein replication protein A (RPA) participates in major DNA transactions. RPA also interacts through its middle subunit (Rpa2) with regulators of the cell division cycle and of the response to DNA damage. A specific contact between Rpa2 and nascent simian virus 40 DNA was revealed by in situ UV cross-linking. The dynamic attributes of the cross-linked DNA, its size distribution, its RNA primer content, and its replication fork polarity were determined [corrected]. These data suggest that Rpa2 contacts the early DNA chain intermediates synthesized by DNA polymerase alpha-primase (RNA-DNA primers) but not more advanced products. Possible signaling functions of Rpa2 are discussed, and current models of eukaryotic lagging-strand DNA synthesis are evaluated in view of our results.
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Affiliation(s)
- G Mass
- Department of Biochemistry, Tel Aviv University, Ramat Aviv 69978, Israel
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38
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Kähler CM, Herold M, Kaufmann G, Pischel AB, Schratzberger P, Reinisch N, Gruber B, Bellmann R, Dunzendorfer S, Kieselbach G, Wiedermann CJ. Induction of arachidonic acid metabolite release by human fibroblasts in proliferative vitreoretinopathy. Eur J Pharmacol 1998; 341:111-7. [PMID: 9489863 DOI: 10.1016/s0014-2999(97)01466-0] [Citation(s) in RCA: 2] [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: 02/06/2023]
Abstract
Proliferative vitreoretinopathy is a severe ocular disorder characterized by unwanted proliferation of cells and excessive production of fibrous tissue, which leads to the formation of cellular membranes on the surface of the retina and in the vitreous. Proliferative vitreoretinopathy is the most common cause of failure in retinal reattachment surgery, approximately occurring in one out of ten operated eyes. Proliferation of retinal pigment epithelial cells and fibroblasts is a cornerstone in the pathogenesis of proliferative vitreoretinopathy. An in vitro-proliferation assay showed previously that intraocular fluid from patients with proliferative vitreoretinopathy is potently effective in stimulating proliferation of human fibroblasts. Here we show that exposure of human fibroblasts to vitreous fluids from patients with proliferative vitreoretinopathy causes a rapid and sustained increase in arachidonic acid metabolite release as measured by competitive enzyme-immunoassay. The findings implicate prostaglandin E2 as a contributor to enhanced intraocular fibrosis in proliferative vitreoretinopathy. As prostaglandin E2 is a mediator of continuous aqueous-blood retinal barrier breakdown in this severe disease, cycclooxygenase inhibitors such as acetylsalicylic acid, which was successfully used in this study for blocking the effect of intraocular fluid, may be useful agents in targeting the progression of intraocular fibrosis.
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Affiliation(s)
- C M Kähler
- Department of Internal Medicine, Faculty of Medicine, University of Innsbruck, Austria.
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39
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Kähler CM, Kirchmair R, Kaufmann G, Kähler ST, Reinisch N, Fischer-Colbrie R, Hogue-Angeletti R, Winkler H, Wiedermann CJ. Inhibition of proliferation and stimulation of migration of endothelial cells by secretoneurin in vitro. Arterioscler Thromb Vasc Biol 1997; 17:932-9. [PMID: 9157958 DOI: 10.1161/01.atv.17.5.932] [Citation(s) in RCA: 35] [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] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Vascular cell responses in inflammation are affected by several neuropeptides of perivascular nerve fibers. Secretoneurin is a 33-amino acid peptide that is coreleased from these nerve endings with other proinflammatory neuropeptides, eg, substance P and calcitonin gene-related peptide. Furthermore, secretoneurin has been shown to be chemotactic for human skin fibroblasts and human blood monocytes in vitro and in vivo. An action on cellular components of the vascular wall is not yet reported. We therefore investigated in vitro effects of this novel sensory neuropeptide on endothelial cells. Secretoneurin exerted a potent and reversible inhibitory effect both on endothelial cell growth under low serum conditions (1% fetal calf serum) and endothelial cell growth factor-activated endothelial cell proliferation. We show in the present study that secretoneurin exerts this effect on aortic (rat) and pulmonary artery (bovine) endothelial cells, as well as venous (human umbilical vein) endothelium. Endothelial cell chemotaxis was tested by means of three different migration assays employing nitrocellulose and polycarbonate micropore filters. Secretoneurin consistently exhibited potent chemoattractant activity. The effective concentrations for the observed effects were in the picomolar range. The combination of chemotactic and antiproliferative effects on endothelial cells suggests that secretoneurin may act as a regulatory factor of vascular cell functions.
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Affiliation(s)
- C M Kähler
- Department of Internal Medicine, Faculty of Medicine, University of Innsbruck, Anichstrasse, Austria
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40
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Affiliation(s)
- Th. Hanser
- Laboratoire de Modèles Informatiques Appliqués à la Synthèse, URA 405 du CNRS, Université Louis Pasteur, 67000 Strasbourg, France
| | - Ph. Jauffret
- Laboratoire de Modèles Informatiques Appliqués à la Synthèse, URA 405 du CNRS, Université Louis Pasteur, 67000 Strasbourg, France
| | - G. Kaufmann
- Laboratoire de Modèles Informatiques Appliqués à la Synthèse, URA 405 du CNRS, Université Louis Pasteur, 67000 Strasbourg, France
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41
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42
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Goetz-Grandmont G, Chaoui Roqai M, Brunette J, Kaufmann G. MOLECULAR MODELLING AND SPECTROSCOPIC STUDIES OF THE INTERACTIONS BETWEEN CHELATING AND ELECTRON-DONOR METAL EXTRACTANTS: THE SYSTEM TRI-N-OCTYLPHOSPHINE OXIDE - 3-PHENYL-4-BENZOYL-ISOXAZOL-5-ONE ( ‘HPBI‘ ) IN WET TOLUENE AND CHLOROFORM. Solvent Extraction and Ion Exchange 1996. [DOI: 10.1080/07366299608918362] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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43
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Zlotkin T, Kaufmann G, Jiang Y, Lee MY, Uitto L, Syväoja J, Dornreiter I, Fanning E, Nethanel T. DNA polymerase epsilon may be dispensable for SV40- but not cellular-DNA replication. EMBO J 1996; 15:2298-305. [PMID: 8641295 PMCID: PMC450155] [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] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
The contributions of DNA polymerases alpha, delta, and epsilon to SV40 and nuclear DNA syntheses were evaluated. Proteins were UV-crosslinked to nascent DNA within replicating chromosomes and the photolabelled polymerases were immunopurified. Only DNA polymerases alpha and delta were detectably photolabelled by nascent SV40 DNA, whether synthesized in soluble viral chromatin or within nuclei isolated from SV40-infected cells. In contrast, all three enzymes were photolabelled by the nascent cellular DNA. Mitogenic stimulation enhanced the photolabelling of the polymerases in the alpha>delta>epsilon order of preference. The data agree with the notion that DNA polymerases alpha and delta catalyse the principal DNA polymerisation reactions at the replication fork of SV40 and, perhaps, also of nuclear chromosomes. DNA polymerase epsilon, implicated by others as a cell-cycle checkpoint regulator sensing DNA replication lesions, may be dispensable for replication of the small, fast propagating virus that subverts cell cycle controls.
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Affiliation(s)
- T Zlotkin
- Department of Biochemistry, Tel Aviv University, Ramat Aviv, Israel
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44
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Abstract
The optional Escherichia coli prr locus encodes two physically associated restriction systems: the type IC DNA restriction-modification enzyme EcoprrI and the tRNA(Lys)-specific anticodon nuclease, specified by the PrrC polypeptide. Anticodon nuclease is kept latent as a result of this interaction. The activation of anticodon nuclease, upon infection by phage T4, may cause depletion of tRNA(Lys) and, consequently, abolition of T4 protein synthesis. However, this effect is counteracted by the repair of tRNA(Lys) in consecutive reactions catalysed by the phage enzymes polynucleotide kinase and RNA ligase. Stp, a short polypeptide encoded by phage T4, has been implicated with activation of the anticodon nuclease. Here we confirm this notion and also demonstrate a second function of Stp: inhibition of EcoprrI restriction. Both effects depend, in general, on the same residues within the N-proximal 18 residue region of Stp. We propose that Stp alters the conformation of EcoprrI and, consequently, of PrrC, allowing activation of the latent anticodon nuclease. Presumably, Stp evolved to offset a DNA restriction system of the host cell but was turned, eventually, against the phage as an activator of the appended tRNA restriction enzyme.
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Affiliation(s)
- M Penner
- Department of Biochemistry Tel Aviv University, Israel
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45
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Shterman N, Elroy-Stein O, Morad I, Amitsur M, Kaufmann G. Cleavage of the HIV replication primer tRNALys,3 in human cells expressing bacterial anticodon nuclease. Nucleic Acids Res 1995; 23:1744-9. [PMID: 7784179 PMCID: PMC306931 DOI: 10.1093/nar/23.10.1744] [Citation(s) in RCA: 11] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Anticodon nuclease is a bacterial restriction enzyme directed against tRNA(Lys). We report that anticodon nuclease also cleaves mammalian tRNA(Lys) molecules, with preference and site specificity shown towards the natural substrate. Expression of the anticodon nuclease core polypeptide PrrC in HeLa cells from a recombinant vaccinia virus elicited cleavage of intracellular tRNA(Lys),3. The data justify an inquiry into the possible application of anticodon nuclease as an inhibitor of tRNA(Lys),3-primed HIV replication. They also indicate that the anticodon region of tRNA(Lys) is a substrate recognition site and suggest that PrrC harbors the enzymatic activity.
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Affiliation(s)
- N Shterman
- Department of Biochemistry, Tel Aviv University, Israel
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46
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Kaufmann G, Cleland J. Maternal education and child survival: anthropological responses to demographic evidence. Health Transit Rev 1994; 4:196-9. [PMID: 10150519] [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: 04/12/2023]
Affiliation(s)
- G Kaufmann
- MacArthur Program in Population and Development Center for Population and Development Studies, Cambridge MA, USA
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47
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Sobek L, Di Lorenzo D, Oettel M, Kaufmann G. Normal and stable transfected cancer cell lines: tools for a screening of progestogenic, antiprogestogenic and antiglucocorticoid substances. Methods Find Exp Clin Pharmacol 1994; 16:545-51. [PMID: 7885082] [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: 01/27/2023]
Abstract
Synthetic ligands for steroid receptors represent important drugs in the control of fertility and in the therapy of a large variety of endocrinological diseases. In the present study we describe the establishment of different biochemical and molecular biological screening methods. We developed a microtiter plate assay for the induction of the de novo synthesis of alkaline phosphatase in T47D cells as a suitable and fast system for the measurement of actions of progestogenic and antiprogestogenic compounds. We compared several progestogenic activities with relative molar binding affinities (RBA) to the progesterone receptor. The ED50 values for the induction of alkaline phosphatase are in good accordance with RBA to the progesterone receptor. Furthermore, glucocorticoid and antiglucocorticoid effects were measured in the stable transfected breast cancer cell line ZR75/-763AGP-CAT. The construct AGP-CAT contains the glucocorticoid responsible element of the rat alpha-1-acid glycoprotein (AGP) gene with the bacterial chloramphenicol acetyltransferase (CAT) gene. The rat hepatoma Reuber cell line H4-II-E with the tyrosine aminotransferase gene is a further suitable marker of glucocorticoid action and was used as a second model for glucocorticoid activity. Thus, we demonstrated in three cell systems the antiprogestogenic and antiglucocorticoid activities of the model compound mifepristone.
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Affiliation(s)
- L Sobek
- Jenapharm GmbH, Department of Research and Development, Jena, Germany
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48
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Kaufmann G. [A case from practice (293). HIV-infection and histoplasmosis]. Schweiz Rundsch Med Prax 1994; 83:525-526. [PMID: 8191197] [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: 05/22/2023]
Affiliation(s)
- G Kaufmann
- Medizinische Universitätspoliklinik, Kantonsspital, Basel
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49
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Morad I, Chapman-Shimshoni D, Amitsur M, Kaufmann G. Functional expression and properties of the tRNA(Lys)-specific core anticodon nuclease encoded by Escherichia coli prrC. J Biol Chem 1993; 268:26842-9. [PMID: 8262917] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Escherichia coli carrying the optional locus prr harbor a latent, tRNA(Lys)-specific anticodon nuclease, activated by the product of phage T4 stp. Anticodon nuclease latency is ascribed to the masking of prrC, implicated with the enzymatic activity, by flanking, type Ic DNA restriction modification genes (prrA, B&D-hsdM, S&R). Overexpression of plasmid-borne prrC elicited anticodon nuclease activity in uninfected E. coli. In vitro, the prr-C-coded core activity was indifferent to a synthetic Stp polypeptide, GTP, ATP, and endogenous DNA, effectors that synergistically activate the latent enzyme. Several facts suggested that PrrC is highly labile in the absence of the masking proteins. The core activity decayed with t1/2 below 1 min at 30 degrees C, and the PrrC portion of a fusion protein was unstable. Moreover, expression of prrC from its own promoter at low plasmid copy number did not allow detection of core activity. Yet, it sufficed for establishment of a latent, T4-inducible enzyme when complemented by the masking Hsd proteins, which were provided by another replicon. Interaction between the antagonistic components of latent anticodon nuclease was also demonstrated immunochemically. The coupling of anticodon nuclease with a DNA restriction modification system may serve to ward off its inadvertent toxicity and maintain it as an antiviral contingency.
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Affiliation(s)
- I Morad
- Department of Biochemistry, Tel Aviv University, Ramat Aviv, Israel
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50
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Morad I, Chapman-Shimshoni D, Amitsur M, Kaufmann G. Functional expression and properties of the tRNA(Lys)-specific core anticodon nuclease encoded by Escherichia coli prrC. J Biol Chem 1993. [DOI: 10.1016/s0021-9258(19)74188-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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