Search

Your search keyword '"Wolff T"' showing total 78 results
Start Over Author "Wolff T" Language undetermined
78 results on '"Wolff T"'

2. Developing Recommendations for Evidence-Based Clinical Preventive Services for Diverse Populations: Methods of the U.S. Preventive Services Task Force

Author

Bibbins-Domingo, K, Whitlock, E, Wolff, T, Ngo-Metzger, Q, Phillips, WR, Davidson, KW, Krist, AH, Lin, JS, Mangione, CM, Kurth, AE, Garcia, FAR, Curry, SJ, Grossman, DC, Landefeld, CS, Jr, EJW, and Siu, AL

Subjects
Evidence-Based Medicine, Information Dissemination, Prostate Cancer, Prevention, Advisory Committees, Diabetes, Health Services, Medical and Health Sciences, United States, Research Design, Clinical Research, General & Internal Medicine, Preventive Health Services, Practice Guidelines as Topic, Breast Cancer, Humans, Cancer
Abstract

The U.S. Preventive Services Task Force (USPSTF) summarizes the principles and considerations that guide development of its recommendations for diverse U.S. populations. It uses these principles through each step in the evidence-based guideline process: developing the research plan, conducting the evidence review, developing the recommendation, and communicating to guideline users. Three recent recommendations provide examples of how the USPSTF has used these principles: the 2015 recommendation on screening for abnormal blood glucose and type 2 diabetes; the 2016 recommendation on screening for breast cancer; and the recommendation on screening for prostate cancer, which is currently in progress. A more comprehensive list of recommendations that includes considerations for specific populations is also provided.

Published
2017

3. Measurement of charm production in antineutrino charged-current interactions

Author

Onengüt, G, Van Dantzig, R, De Jong, M, Konijn, J, Melzer, O, Oldeman, R G C, Pesen, E, Van der Poel, C A F J, Visschers, J L, Güler, M, Köse, U, Serin-Zeyrek, M, Kama, S, Sever, R, Tolun, P, Zeyrek, M T, Catanesi, M G, De Serio, M, Ieva, M, Muciaccia, M T, Radicioni, E, Simone, S, Bülte, A, Winter, Klaus, Van de Vyver, B, Vilain, P, Wilquet, G, Saitta, B, Di Capua, E, Ogawa, S, Shibuya, H, Artamonov, A V, Brunner, J, Chizhov, M, Cussans, D G, Doucet, M, Fabre, Jean-Paul, Hristova, I R, Kawamura, T, Kolev, D, Litmaath, M, Meinhard, H, Panman, J, Papadopoulos, I M, Ricciardi, S, Rozanov, A, Saltzberg, D, Tsenov, R V, Uiterwijk, J W E, Zucchelli, P, Goldberg, J, Chikawa, M, Arik, E, Song, J S, Yoon, C S, Kodama, K, Ushida, N, Aoki, S, Hara, T, Delbar, T, Favart, D, Grégoire, G, Kalinin, S, Makhlyoueva, I V, Gorbunov, P, Khovanskii, V D, Shamanov, V V, Tsukerman, I, Bruski, N, Frekers, D, Rondeshagen, D, Wolff, T, Hoshino, K, Kawada, J, Komatsu, M, Miyanishi, M, Nakamura, M, Nakano, T, Narita, K, Niu, K, Niwa, K, Nonaka, N, Sato, O, Toshito, T, Buontempo, S, Cocco, A G, D'Ambrosio, N, De Lellis, G, De Rosa, G, Di Capua, F, Ereditato, A, Fiorillo, G, Marotta, A, Messina, M, Migliozzi, P, Pistillo, C, Santorelli, R, Scotto-Lavina, L, Strolin, P, Tioukov, V, Nakamura, K, Okusawa, T, Dore, U, FLoverre, P, Ludovici, L, Maslennikov, A L, Righini, P, Rosa, G, Santacesaria, R, Satta, A, Spada, F R, Barbuto, E, Bozza, C, Grella, G, Romano, G, Sirignano, C, Sorrentino, S, Sato, Y, Tezuka, I, Other Research IHEF (IoP, FNWI), UCL - SC/PHYS - Département de physique, Çukurova Üniversitesi, Önengüt, G., van Dantzig, R., de Jong, M., Melzer, O., Oldeman, R. G. C., Pesen, E., Visschers, J. L., Güler, M., Köse, U., Serin Zeyrek, M., Sever, R., Tolun, P., Zeyrek, M. T., Catanesi, M. G., De Serio, M., Ieva, M., Muciaccia, M. T., Radicioni, E., Simone, S., Bülte, A., Winter, K., Van de Vyver, B., Vilain, P., Wilquet, G., Saitta, B., Di Capua, E., Ogawa, S., Shibuya, H., Artamonov, A., Chizhov, M., Doucet, M., Hristova, I. R., Kayis Topaksu, A., Kawamura, T., Kolev, D., Meinhard, H., Panman, J., Papadopoulos, I. M., Ricciardi, S., Rozanov, A., Tsenov, R., Uiterwijk, J. W. E., Zucchelli, P., Goldberg, J., Chikawa, M., Arik, E., Song, J. S., Yoon, C. S., Kodama, K., Ushida, N., Aoki, S., Hara, T., Delbar, T., Favart, D., Grégoire, G., Kalinin, S., Makhlioueva, I., Gorbunov, P., Khovansky, V., Shamanov, V., Tsukerman, I., Bruski, N., Frekers, D., Hoshino, K., Kawada, J., Komatsu, M., Miyanishi, M., Nakamura, M., Nakano, T., Narita, K., Niu, K., Niwa, K., Nonaka, N., Sato, O., Toshito, T., Buontempo, S., Cocco, A. G., D'Ambrosio, N., De Lellis, G., De Rosa, G., DI CAPUA, Francesco, Ereditato, A., Fiorillo, Giuliana, Marotta, A., Messina, M., Migliozzi, P., Pistillo, C., Scotto Lavina, L., Strolin, P., Tioukov, V., Nakamura, K., Okusawa, T., Dore, U., Loverre, P. F., Ludovici, L., Righini, P., Rosa, G., Santacesaria, R., Satta, A., Spada, F. R., Barbuto, E., Bozza, C., Grella, G., Romano, G., Sirignano, C., Sorrentino, S., Sato, Y., Tezuka, I., G., Onengut, R. v., Dantzig, M. d., Jong, O., Melzer, R. G., C., E., Pesen, J. L., Visscher, M., Guler, U., Kose, M., Serin Zeyrek, R., Sever, P., Tolun, M. T., Zeyrek, M. G., Catanesi, M. D., Serio, M., Ieva, M. T., Muciaccia, E., Radicioni, S., Simone, A., Bulte, K., Winter, B. V., De, P., Vilain, G., Wilquet, B., Saitta, E. D., Capua, S., Ogawa, H., Shibuya, A., Artamonov, M., Chizhov, M., Doucet, I. R., Hristova, A., Kayis Topaksu, T., Kawamura, D., Kolev, H., Meinhard, J., Panman, I. M., Papadopoulo, S., Ricciardi, A., Rozanov, R., Tsenov, J. W., E., P., Zucchelli, J., Goldberg, M., Chikawa, J. S., Song, C. S., Yoon, K., Kodama, N., Ushida, S., Aoki, T., Hara, T., Delbar, D., Favart, G., Gregoire, S., Kalinin, I., Makhlioueva, P., Gorbunov, V., Khovansky, V., Shamanov, I., Tsukerman, N., Bruski, D., Freker, K., Hoshino, J., Kawada, M., Komatsu, M., Miyanishi, M., Nakamura, T., Nakano, K., Narita, K., Niu, K., Niwa, N., Nonaka, O., Sato, T., Toshito, S., Buontempo, A. G., Cocco, N., D'Ambrosio, DE LELLIS, Giovanni, DE ROSA, Gianfranca, A., Ereditato, A., Marotta, M., Messina, P., Migliozzi, C., Pistillo, L. S., Lavina, P., Strolin, V., Tioukov, K., Nakamura, T., Okusawa, U., Dore, P. F., Loverre, L., Ludovici, P., Righini, G., Rosa, R., Santacesaria, A., Satta, F. R., Spada, E., Barbuto, C., Bozza, G., Grella, G., Romano, C., Sirignano, S., Sorrentino, Y., Sato, and I., Tezuka

Subjects
Physics, NEUTRINO INTERACTIONS, CHORUS EXPERIMENT, Nuclear and High Energy Physics, Particle physics, Muon, Large Hadron Collider, Physics::Instrumentation and Detectors, High Energy Physics::Phenomenology, Charge (physics), BEAMS, EVENTS, Nuclear physics, OPPOSITE-SIGN DIMUONS, High Energy Physics::Experiment, Production (computer science), Charm (quantum number), Neutrino, Nuclear Experiment, Particle Physics - Experiment, Charged current, Beam (structure)
Abstract

During the years 1994-1997, the emulsion target of the CHORUS detector was exposed to the wide-band neutrino beam of the CERN SPS collecting about 10 6 neutrino interactions. A measurement of ?¯µ-induced charm production is performed by using the presence of a 5% ?¯µ component in the ?µ beam. The measurement takes advantage of the capability to observe the decay topology in the emulsion. The analysis is based on a sample of charged-current interactions with at least one identified muon. About 100000 were located in the emulsion target and fully reconstructed. By requiring a positive muon charge as determined by the CHORUS muon spectrometer, 32?¯µ-induced charm events were observed with an estimated background of 3.2 events. At an average antineutrino energy in the neutrino beam of 18 GeV, the charm production rate induced by antineutrinos is measured to be ?(?¯µN›µ+c¯X)/?(?¯µN›µ+X) =(5.0-0.9+1.4(stat)±0.7(syst))%. The ratio between neutral and charged charm production rates in this process is (2.6-1.0+1.7(stat)±0.8(syst)). The charm production rate as a function of the antineutrino energy is found to be in good agreement with previous results derived from di-lepton data. © 2004 Elsevier B.V. All rights reserved. Bundesministerium für Bildung und Forschung Promotion and Mutual Aid Corporation for Private Schools of Japan Grant Foundation: KRF-2003-005-C00014 Israel Science Foundation: 328/94 CERN Brussels Instituut voor Milieubeheer Instituto Nazionale di Fisica Nucleare Foundation for Fundamental Research on Matter Korean Foundation for Cancer Research We gratefully acknowledge the help and support of the neutrino-beam staff and of the numerous technical collaborators who contributed to the detector construction, operation, emulsion pouring, development, and scanning. The experiment was made possible by grants from the Institut Interuniversitaire des Sciences Nucléaires and the Interuniversitair Instituut voor Kernwetenschappen (Belgium); the Israel Science Foundation (Grant 328/94) and the Technion Vice President Fund for the Promotion of Research (Israel); CERN (Geneva, Switzerland); the German Bundesministerium für Bildung und Forschung (Germany); the Institute of Theoretical and Experimental Physics (Moscow, Russia); the Istituto Nazionale di Fisica Nucleare (Italy); the Promotion and Mutual Aid Corporation for Private Schools of Japan and Japan Society for the Promotion of Science (Japan); Korea Research Foundation Grant (KRF-2003-005-C00014) (Republic of Korea); the Foundation for Fundamental Research on Matter FOM and the National Scientific Research Organization NWO (The Netherlands); and the Scientific, and Technical Research Council of Turkey (Turkey). We gratefully acknowledge their support.

Published
2004

4. Laboratory capability and surveillance testing for middle east respiratory syndrome coronavirus infection in the who European region, June 2013

Author

Pereyaslov, D., Rosin, P., Palm, D., Zeller, H., Gross, D., Brown, C. S., Struelens, M. J., Robo, A., Hatibi, I. H., Alis, J. C., Sargsyan, S., Gurbanov, S., Gribkova, N., Ranst, M., Ieven, G., Patteet, S., Tomic, S., Korsun, N., Drazenovic, V., Pieridou-Bagkatzouni, D., Jirincova, H., Havlickova, M., Fomsgaard, A., Rae, K., Lappalainen, M., Ikonen, N., Lina, B., Sylvie van der WERF, Manuguerra, J. -C, Machablishvili, A., Eickmann, M., Wolff, T., Dobler, G., Schmidt-Chanasit, J., Drosten, C., Papa, A., Mentis, A. F., Kis, Z., Löve, A., Coughlan, S., Mandelboim, M., Capobianchi, M. R., Landini, M. P., Baldanti, F., Palu, G., Ghisetti, V., Donatelli, I., Nusupbayeva, G., Tokhtabakiyeva, Z., Kasymbekova, K., Storozenko, J., Erne, S., Griskevicius, A., Opp, M., Barbara, C., Vratnica, Z., Reusken, C., Dudman, S. G., Hungnes, O., Pancer, K., Guiomar, R., Eder, V., Lupulescu, E., Yatsyshina, S., Pisareva, M., Buzitskaya, Z., Sergeev, A., Nedeljković, J., Staroňová, E., Županc, T. A., Petrovec, M., Korva, M., Prosenc, K., Casas, I., Gaines, H., Cherpillod, P., Zakirova, N., Bosevska, G., Altas, B., Ciblak, M., Mironenko, A., Dykhanovska, T., Demchyshyna, I., Bermingham, A., Rakhimov, R., Organisation Mondiale de la Santé / World Health Organization Office (OMS / WHO), European Centre for Disease Prevention and Control [Stockholm, Sweden] (ECDC), Experts of the MERS-CoV Working Group Members of this working group who provided survey data: Albania: Alma Robo, Iris Hasibra (Hatibi), Institute of Public Health, Tirana Andorra: Josep Casals Alis, Ministry of Health, Welfare and Labour, Andorra la Vella Armenia: Shushan Sargsyan, Virology Laboratory, Centre for Diseases Control and Prevention, Yerevan Austria: Stephan Aberle, Department of Virology, Medical University of Vienna, Vienna Azerbaijan: Sadraddin Gurbanov, National Virology Laboratory, National Anti-Plague Station, Baku Belarus: Natalia Gribkova, Laboratory for Influenza and Influenza-like Diseases, Republican Research and Practical Center for Epidemiology and Microbiology, Minsk Belgium: Marc Van Ranst, Greet Ieven and Sophie Patteet, National Reference Centre of Respiratory Viruses, University Hospital Leuven and UZA Antwerpen, Antwerpen Bosnia and Herzegovina: Stanka Tomic, Microbiology Department, Institute of Public Health of the Republic of Srpska, Banja Luka Bulgaria: Neli Korsun, National Laboratory 'Influenza and ARD', Department of Virology, National Centre of Infectious and Parasitic Diseases, Sofia Croatia: Vladimir Drazenovic, National Influenza Centre, Croatian National Institute of Public Health, Zagreb Cyprus: Despo Pieridou-Bagkatzouni, Microbiology Department, Nicosia General Hospital, Nicosia Czech Republic: Helena Jirincova, Martina Havlickova, National Reference Laboratory for Influenza, National Institute for Public Health, Prague Denmark: Anders Fomsgaard, Virus Research and Development Laboratory, Department Microbiology Diagnostic and Virology, Statens Serum Institut, Copenhagen Estonia: Külli Rae, Laboratory of Communicable Diseases, Health Board, Tallinn Finland: Maija Lappalainen, Department of Virology and Immunology, Helsinki University Hospital, Laboratory Services (HUSLAB) and Niina Ikonen, Virology Unit, National Institute for Health and Welfare, Helsinki France: Bruno Lina, Centre National de Référence des Virus Influenza – HCL, Lyon and Sylvie van der Werf, Unit of Molecular Genetics of RNA viruses, Institut Pasteur and Jean-Claude Manuguerra, Cellule d’Intervention Biologique d’Urgence (CIBU), Institut Pasteur, Paris Georgia: Ann Machablishvili, National Influenza Centre, National Centre for Disease Control and Public Health, Tbilisi Germany: Markus Eickmann, Institut für Virologie der Philipps-Universität in Marburg and Thorsten Wolff, Div of Influenza and other Respiratory viruses, Robert Koch-Institut, and Dr. Gerhard Dobler, Bundeswehr Instittue of Microbiology, and Jonas Schmidt-Chanasit, WHOCC for Arbovirus and Haemorrhagic Fever Reference and Research at Bernhard Nocht Institute for Tropical Medicine, Hamburg, and Christian Drosten, Virology Institute, Bonn Greece: Anna Papa, National Reference Laboratory for Arboviruses and Hemorrhagic Fever viruses, Aristotle University of Thessaloniki, Thessaloniki and Andreas F. Mentis, National Influenza Reference Laboratory of Southern Greece/Hellenic Pasteur Institute, Athens Hungary: Zoltan Kis, Department for Respiratory Viruses / National Biosafety Laboratory, B. Johan National Center for Epidemiology, Budapest Iceland: Arthur Löve, Department of Virology, Landspitali- National University Hospital, Reykjavik Ireland: Suzie Coughlan, National Virus Reference Laboratory/University College Dublin, Dublin Israel: Michal Mandelboim, Central Virology Laboratory, Sheba Medical Center, Tel Hashomer Italy: Maria R. Capobianchi, Laboratory of Virology/National Institute for Infectious Diseases Lazzaro Spallanzani, and Maria Paola Landini, Regional Center for Emerging Infections (CRREM)/ Unit of Clinical Microbiology, St. Orsola General Hospital, Bologna, and Fausto Baldanti, Molecular Virology Unit, Department of Microbiology and Virology, Fondazione IRCCS Policlinico San Matteo, Pavia, and Giorgio Palu, Microbiology and Virology/Padova University Hospital, and Valeria Ghisetti, Laboratory of Microbiology and Virology, Amedeo di Savoia Hospital, Torino, and Isabella Donatelli, National Influenza Centre, Instituto Superiore di Sanita, Kazakhstan: Gaukhar Nusupbayeva, Zarina Tokhtabakiyeva, National Reference Laboratory on Control of Viral Infections, Scientifical-Practical Center of Sanitary and Epidemiological Expertise and Monitoring, Almaty Kyrgyzstan: Kaliya Kasymbekova, Centre of Molecular-Genetic and Microbiological Investigations, Department of State Sanitary Epidemiological Surveillance, Bishkek Latvia: Jelena Storozenko, Riga East University Hospital, Latvian Centre of Infectious Diseases, National Microbiology Reference Laboratory, Riga Liechtenstein: Sabine Erne, Office of Public Health, Country Administration of Principality of Liechtenstein Lithuania: Algirdas Griskevicius, National Public Health Surveillance Laboratory, Vilnius Luxembourg: Matthias Opp, Laboratoire National de Santé, Luxembourg Malta: Christopher Barbara, Pathology Department, Mater Dei Hospital, Msida Montenegro: Zoran Vratnica, Centre for Medical Microbiology, Public Health Institute of Montenegro, Podgorica Netherlands: Chantal Reusken, Centre for Infectious Disease Research, Diagnostics and Screening, National Institute for Public Health and the Environment, Bilthoven Norway: Susanne Gjeruldsen Dudman and Olav Hungnes, Department of Virology, Norwegian Institute of Public Health, Oslo Poland: Katarzyna Pancer, National Institute of Public Health- National Institute of Hygiene, Department of Virology, Warsaw Portugal: Raquel Guiomar, National Influenza Reference Laboratory, Infectious Diseases Department, National Institute of Health, Lisboa Republic of Moldova: Veronica Eder, Laboratory of Viral Respiratory Infections, National Center for Public Health, Chisinau Romania: Emilia Lupulescu, Laboratory for Respiratory Viruses/ NIRDMI Cantacuzino, Bucharest Russian Federation: Svetlana Yatsyshina, Reference Centre for Infection Agents, Central Research Institute of Epidemiology (CRIE), Rospotrebnadzor, Moscow, and Maria Pisareva and Zhanna Buzitskaya, Laboratory of Molecular Virology and Genetic Engineering, Research Institute of Influenza, St Petersburg, and Alexander Sergeev, State Research Center of Virology and Biotechnology VECTOR, Novosibirsk Serbia: Jasminka Nedeljković, Respiratory Department, Torlak Institute of Immunology and Virology, Belgrade Slovakia: Edita Staroňová, National Influenza Center/Public Health Authority, Bratislava Slovenia: Tatjana Avšič Županc, Miroslav Petrovec, Miša Korva, University of Ljubljana, Faculty of Medicine, Institute of Microbiology and Immunology, and Katarina Prosenc, Laboratory for Virology, National Public Health Institute Slovenia, Ljubljana Spain: Inmaculada Casas, Influenza National Reference Laboratory, National Influenza Center-Madrid, Instituto de Salud Carlos III, Majadahonda, Madrid and Ramon Cisterna Clinical microbiology and infection control, Hospital Basurto Bilbao Spain Sweden: Hans Gaines, Swedish Institute for Communicable Disease Control, Stockholm Switzerland: Pascal Cherpillod, National Reference Centre for Emerging Viral Infections, Laboratory of Virology, Division of Infectious Diseases University of Geneva Hospitals, Geneva Tajikistan: Niginamo Zakirova, Virology Laboratory, State Sanitary-Epidemiological Surveillance, Dushanbe The former Yugoslav Republic of Macedonia: Golubinka Bosevska, Laboratory for Virology and Molecular Diagnostics, Institute of Public Health, Skopje Turkey: Basak Altas, National Influenza Centre, Virology Reference and Research Laboratory, Public Health Institutions of Turkey, Ankara, and Meral Ciblak, National Influenza Reference Laboratory, Faculty of Medicine, University of Istanbul, Istanbul Turkmenistan: Central Reference Laboratory, Sanitary Epidemiologic Service, Ashgabat Ukraine: Alla Mironenko, National Influenza Centre, L.V.Gromashevsky Institute of Epidemiology & Infectious diseases NAMS, and Tetiana Dykhanovska and Iryna Demchyshyna, Centre of influenza and ARVI, Central Sanitary and Epidemiological Station, Kiev United Kingdom: Alison Bermingham, Respiratory Virus Unit, Virus Reference Department, Public Health England, London Uzbekistan: Ravshan Rakhimov, National Influenza Centre, Institute of Virology, Tashkent., and We thank the ECDC National Microbiology Focal Points in EU/EEA countries, focal points from laboratories of the EuroFlu and ENIVD networks for coordinating data collection and for dedicated and rapid responses to the surveys.

Subjects
Epidemiology, Middle East respiratory syndrome coronavirus, [SDV]Life Sciences [q-bio], SARS (Disease), MERS (Disease), medicine.disease_cause, World Health Organization, Communicable Diseases, Emerging, World health, Viral genetics, Coronavirus infections -- Laboratory manuals, Environmental protection, Virology, Environmental health, medicine, media_common.cataloged_instance, Humans, European Union, European union, Coronavirus, media_common, Middle East, business.industry, Reverse Transcriptase Polymerase Chain Reaction, Public Health, Environmental and Occupational Health, Reference Standards, European region, Health Surveys, Diseases -- Causes and theories of causation, Middle East Respiratory Syndrome Coronavirus, RNA, Viral, Disease prevention, business, Coronavirus Infections, Laboratories, Sentinel Surveillance, Sequence Analysis
Abstract

Since September 2012, over 90 cases of respiratory disease caused by a novel coronavirus, now named Middle East respiratory syndrome coronavirus (MERS-CoV), have been reported in the Middle East and Europe. To ascertain the capabilities and testing experience of national reference laboratories across the World Health Organization (WHO) European Region to detect this virus, the European Centre for Disease Prevention and Control (ECDC) and the WHO Regional Office for Europe conducted a joint survey in November 2012 and a follow-up survey in June 2013. In 2013, 29 of 52 responding WHO European Region countries and 24 of 31 countries of the European Union/European Economic Area (EU/EEA) had laboratory capabilities to detect and confirm MERS-CoV cases, compared with 22 of 46 and 18 of 30 countries, respectively, in 2012. By June 2013, more than 2,300 patients had been tested in 23 countries in the WHO European Region with nine laboratory-confirmed MERS-CoV cases. These data indicate that the Region has developed significant capability to detect this emerging virus in accordance with WHO and ECDC guidance. However, not all countries had developed capabilities, and the needs to do so should be addressed. This includes enhancing collaborations between countries to ensure diagnostic capabilities for surveillance of MERS-CoV infections across the European Region., peer-reviewed

Published
2014

10. Organic solvents as modifiers of aldrin epoxidase in reconstituted monooxygenase systems and in microsomes

Author

F. P. Guengerich, Wolff T, and Wanders H

Subjects
Male, Hemeprotein, Cytochrome, 1-Propanol, Biochemistry, Mixed Function Oxygenases, Cytochrome P-450 Enzyme System, Cytochrome c oxidase, Animals, Pharmacology, chemistry.chemical_classification, biology, Cytochrome P450, Rats, Inbred Strains, Monooxygenase, Enzyme assay, Rats, Enzyme, chemistry, Enzyme Induction, Phenobarbital, biology.protein, Microsome, Microsomes, Liver, Solvents
Abstract

To examine the response of individual cytochrome P-450 species catalysing the epoxidation of aldrin (Wolff T and Guengerich FP, Biochem Pharmacol 36 : 2581–2588, 1987), monooxygenase systems reconstituted from these species were assayed in the presence of 5% (v/v) = 0.87 M ethanol. The activity of cytochromes P-450 pb.b and P-450 pb-d , two enzymes inducible by phenobarbital was increased seven-fold. The activity of two other P-450 enzymes purified from these animals was either inhibited by 50%, as observed for cytochrome P-450 pb-c or remained unchanged, as noted with cytochrome P-450 pcn-e . Two P-450 enzymes purified from untreated rats, cytochromes P-450 ut-f and P-450 ut-h , showed an inhibition by 50 and 20%, respectively, while the activity of cytochrome P-450 ut-a was slightly increased by 50%. Indirect evidence that solvents enhance aldrin epoxidation by interacting with the hemoprotein was obtained by the finding that ethanol stimulated the activity of cytochrome P-450 pb-b already, before addition of the lipid component, l -α-1,2-dilauroyl-in-glycero-3-phosphocholine. The K m of cytochrome P-450 pb.b for NADPH cytochrome P-450 reductase was not altered by ethanol indicating that the interaction between the two enzymes was not affected by the solvent. Other results indicate that the stimulatory solvent binds to a site, apart from the type I or type II binding site. The potency of various hydrophylic solvents to modify aldrin epoxidase activity was assayed in microsomes of rats pretreated with phenobarbital and of untreated male rats. Ethanol, n -propranol, n -butanol, acetone and tetrahydrofuran enhanced enzyme activity of phenobarbital pretreated rats to a maximal extent of two-fold and, at similar concentrations, inhibited the enzyme activity of untreated rats by 50%. The potency of these solvents correlated with their lipophilicity. Methanol and dimethylsulfoxide only slightly modified the activity of induced and noninduced animals. In the presence of 0.5 M n -propranol as the modifying agent, microsomal epoxidase activity of rats pretreated with pregnenolone-16α-carbonitrile, dexamethasone, 3-methylcholanthrene and of control rats was inhibited by 60–80%, whereas the activity of animals pretreated with phenobarbital, DDT, or the polychlorinated biphenyl mixture, Clophen A 50, was stimulated between two- and three-fold. The results reveal that organic solvents frequently used to dissolve monooxygenase substrates may considerably modify the activity of cytochrome P-450 dependent reactions, in particular when purified enzymes are assayed.

Published
1989

Catalog

Books, media, physical & digital resources
See catalog results