Practising Chemistry in the British Empire: George Christian Hoffmann (1837-1917) and the Geological Survey of Canada

George Christian Hoffmann, of German extraction, was born in London. After studying at the Royal School of Mines and working in London as a chemical analyst, he set out on a career that took him to Natal, in south-east Africa, to Melbourne in the Australian colony of Victoria, and to Canada where he had a long career with the Geological Survey, becoming Deputy Director in 1880 and retiring in 1907. In his work with the Geological Survey, he determined the chemical composition and identity of mineral samples collected by and submitted to the Survey, assessing their economic potential.George Christian Hoffmann, d’origine allemande, est né à Londres. Il a étudié à la Royal School of Mines et a travaillé à Londres comme analyste chimique avant de se lancer dans une carrière qui l’a mené au Natal, dans le sud-est de l’Afrique, à Melbourne, dans la colonie australienne de Victoria, puis au Canada, où il a eu une longue carrière au sein de la Commission géologique du Canada (CGC); il en est devenu le directeur adjoint en 1880, et a pris sa retraite en 1907. À la Commission géologique, il déterminait la composition chimique d’échantillons minéraux recueillis ou reçus par la CGC et définissait ainsi leur identité, et en évaluait le potentiel économique

Significance of histamine formation and release in the development of endotoxic shock: proof of current concepts by randomized controlled studies in rats

The significance of histamine in the initiation and progression of septic (endotoxic) shock is still uncertain. Increased new formation and increased release of histamine are the two hypotheses currently considered as the basis for a causal relationship. Both hypotheses were tested in a standardized rat model of endotoxic shock. Several randomized controlled studies were performed with inhibitors of histamine formation (histidine decarboxylase inhibitors) and of its action via receptors (H1 and H2 receptor antagonists). Two inhibitors of histamine formation (alpha-methylhistidine and alpha-fluoromethylhistidine) in a wide range of doses exerted no significant effects on survival curves for rats in endotoxic shock, despite enzyme inhibition in vitro and in homogenates of liver obtained from rats immediately after death. In addition, three H1 and three H2 receptor antagonists, which were selected on the basis of markedly different antihistaminic efficacies and of defined non-antihistaminic (nonspecific) efficacies, gave no indications of specific histamine-mediated effects on survival parameters in these studies when tested either singly or in various combinations. Thus, histamine cannot be shown to be a predominant factor in the lethal outcome of endotoxic shock in rats

Storage of histamine in the blood following liberation from liver and antrum through trypsin: protective mechanism or a factor promoting pancreatic shock (transl.)

In dogs histamine was predominantly released from liver and antrum by intravenous injection of trypsin. The histamine content of the human liver was found to be high enough to allow the invasion of mg amounts of histamine into the circulation after histamine release. In blood histamine was rapidly taken up by corpuscular elements. At present it cannot be decided whether this mechanism leads to detoxification or to a more powerful action of histamine in the microcirculation