Physostigmine and nitrous oxide in anaesthesia

The present thesis is chiefly concerned with disturbances during recovery from anaesthesia. This area has been poorly studied. Medicine has tended to leave the patient's well-being during the period of wrecoveryM to the powers of nature. At one time~ anaesthetists considered anaesthesia as a good surrogate for sleep. It has proved to be notoriously difficult to eradicate this simplicism because it offers a readily understandable, if misleading, explanation of the action of anaesthetic agents. Such thinking is even perpetuated in the standard pharmacological vocabulary. For example, it is known that no drug or technique we still promise has been found to induce a state of natural sleep~ yet talk about "hypnotics". Ought an anaesthetist~ then to his patient that anaesthesia will be "just like a pleasant sleep"? It is doubtful to what extent contemporary anaesthesia, That erroneously likened to invigorating sleep, is really safe. most illustrious anaesthesiological professional society, the Association of Anaesthetists of Great Britain and Ireland~ displays a noble coat of arms with the motto "In somno securitas". There are occasions when one is inclined to put a question mark after this statement. Fortunately, it is understood nowadays that a good anaesthetic should be less of a pharmacological manipulation tenance of which depresses vital functions and more of a mainnonnill physiological functions in terms of optimal body homeostasis. In other words, an anaesthetic based on preserving, restoring will probably more classical "borrow'd and supporting the functioning of the body closely resemble a pleasant sleep than the likeness of shrunk death" (Shakespeare~ Romeo & Juliet, Act IV, Scene 2~ line 104)

Enzymatic Degradation of PrPSc by a Protease Secreted from Aeropyrum pernix K1

BACKGROUND: An R30 fraction from the growth medium of Aeropyrum pernix was analyzed for the protease that can digest the pathological prion protein isoform (PrP(Sc)) from different species (human, bovine, deer and mouse). METHODOLOGY/PRINCIPAL FINDINGS: Degradation of the PrP(Sc) isoform by the R30 fraction and the purified protease was evaluated using the 6H4 anti-PrP monoclonal antibody. Fragments from the N-terminal and C-terminal of PrP(Sc) were also monitored by Western blotting using the EB8 anti-PrP monoclonal antibody, and by dot blotting using the C7/5 anti-PrP monoclonal antibody, respectively. For detection of smaller peptides from incomplete digestion of PrP(Sc), the EB8 monoclonal antibody was used after precipitation with sodium phosphotungstate. Characterization of the purified active protease from the R30 fraction was achieved, through purification by fast protein liquid chromatography, and identification by tandem mass spectrometry the serine metalloprotease pernisine. SDS-PAGE and zymography show the purified pernisine plus its proregion with a molecular weight of ca. 45 kDa, and the mature purified pernisine as ca. 23 kDa. The purified pernisine was active between 58 °C and 99 °C, and between pH 3.5 and 8.0. The temperature and pH optima of the enzymatic activity of the purified pernisine in the presence of 1 mM CaCl(2) were 105 °C ± 0.5 °C and pH 6.5 ± 0.2, respectively. CONCLUSIONS/SIGNIFICANCE: Our study has identified and characterized pernisine as a thermostable serine metalloprotease that is secreted from A. pernix and that can digest the pathological prion protein PrP(Sc)