Zobrazeno 1 - 10
of 59
pro vyhledávání: '"Rudolf Preussmann"'
Publikováno v:
Food and Chemical Toxicology. 33:625-630
Three varieties of kola nut, Cola acuminata, C. nitida and Garcinia cola, of Nigerian origin, were analysed for their content of primary and secondary amines, and assessed for their relative methylating potential due to nitrosamide formation. Primary
Publikováno v:
Chemical Research in Toxicology. 7:868-876
The acidic nitrosation of hexetidine and hexedine, common antimicrobial agents and drug constituents, leads to a mixture of nitrosamines. The major nitrosamine product, "HEXNO", forms rapidly in yields as high as 60% over the pH range 1-4.8 at incuba
Autor:
Renu Razdan, Rudolf Preussmann, Rajesh Kumar, Lothar Erdinger, Maqsood Siddiqi, Peter Schmezer, Bertold Spiegelhalder
Publikováno v:
Mutation Research/Environmental Mutagenesis and Related Subjects. 292:41-49
Mutagenesis in S. typhimurium and in vitro induction of DNA single-strand breaks in primary rat hepatocytes (DNA-SSB) have been investigated for two new N-nitroso compounds, mononitrosocaffeidine (MNC) and dinitrosocaffeidine (DNC). Mononitrosamidoca
Autor:
Rajesh Kumar, Rudolf Preussmann, Bertold Spiegelhalder, Maqsood Siddiqi, Zia Fazili, C.-D. Wacker
Publikováno v:
Cancer Letters. 65:139-143
The effect of dietary nitrate on endogenous nitrosation of a therapeutic dose of piperazine has been described in five human volunteers who acted as their own controls. The urinary excretion of endogenously formed N-nitrosomonopiperazine (MNPz) range
Autor:
C.-D. Wacker, Rudolf Preussmann, Maqsood Siddiqi, Rajesh Kumar, Bertold Spiegelhalder, P. Mende
Publikováno v:
Carcinogenesis. 13:2179-2182
Salted tea prepared in Kashmir by adding sodium bicarbonate shows high methylating activity (equivalent to 3 p.p.m. N-methylnitrosourea) upon in vitro nitrosation. Pure caffeine treated under conditions of the tea preparation formed caffeidine and ca
Publikováno v:
Carcinogenesis. 13:2435-2441
Toxicological mechanisms involved in organotropism of tumor induction may include cell-specific metabolic activation of the carcinogen, in vivo distribution of active metabolites and persistance of induced DNA damage. In order to elucidate which fact
Publikováno v:
Carcinogenesis. 13:1331-1335
Analytical data on aliphatic amines and nitrate from the most commonly used fresh and sun-dried vegetables, red chillies and a widely consumed beverage, salted tea, are presented from a high risk area for oesophageal and gastric cancer in Kashmir. Ex
Publikováno v:
Cancer Letters. 57:219-222
Nitrosatability of dried Nigerian vegetables and spices was investigated under simulated gastric conditions. N-Nitroso-dimethylamine (NDMA) was the only volatile nitrosamine found above the preformed level except in ugwu where N-nitroso-piperidine (2
Publikováno v:
Carcinogenesis. 11:723-730
The origin of tobacco-specific nitrosamines (TSNA) in mainstream smoke and the possible contribution of synthesis during the smoking procedure was investigated. Addition of the nitrosamine precursors nitrate and nicotine to the tobacco prior to smoki
Autor:
S. Ivankovic, Dymitr Komitowski, Jens Seibel, Rudolf Preussmann, Bertold Spiegelhalder, Maqsood Siddiqi
Publikováno v:
Carcinogenesis. 19(5)
Mononitrosocaffeidine (MNC) and dinitrosocaffeidine (DNC) are new N-nitroso compounds obtained from in vitro nitrosation of caffeidine, a hydrolysis product of caffeine present in a typically made and widely consumed tea from Kashmir (India), a high