Differential scanning calorimetric measurement of cartilage destruction caused by Gram-negative septic arthritis

The treatment of the bacterial arthritis of the joints is still a great challenge for orthopedic surgeons and rheumatologists. Aerobic Gram-negative bacteria are involved only in 20–25 % of cases. The inadequate therapy can cause cartilage destruction and can result in severe osteoarthritis of the affected joint. The aim of this study was to demonstrate and follow the destruction of the joints’ hyaline cartilage by calorimetric method. We induced experimental septic arthritis in knee joints of seven New Zealand rabbits by a single inoculation of Escherichia coli ATCC 25922 culture (0.5 mL cc. 10⁸ ± 5 % c.f.u.). The duration of this experiment was 7 days from the first to the last injection. After euthanizing the first subject, all other animals were given an overdose of anesthetics and samples were isolated from the cartilage of the femurs by surgical intervention for calorimetric measurements. The DSC scans clearly demonstrated the development of infective structural destruction in the cartilage from the first to the tenth day of incubation. In case of healthy control the melting temperatures (T _m) were: 57 and 63.1 °C and the total calorimetric enthalpy change (ΔH) was 0.37 J g^?1. After the third day, the enthalpy increased extremely (3.67 J g^?1), the two transition temperatures shifted toward lower temperature: 47.7 and 62.3 °C. At the fifth day, the effect of infection is culminated with T _m = 62.2 °C and a further elevation in ΔH (3.75 J g^?1). These results can indicate a dramatic change of the structure of rabbit cartilage between the third and fifth days. Therefore, the time elapsed seems to be critical and possesses clinical relevance, since by the sixth day, ΔH decreased to 2.6 J g^?1 with a practically unchanged melting temperature. Between the sixth and tenth days, significantly increased melting temperatures (64.9 °C) were observed with decreased (3.38 J g^?1) calorimetric enthalpy. In conclusion, calorimetric measurements have been proven to be a reliable method in the measurement of cartilage destruction, caused by Gram-negative septic arthritis.     

Thioflavin S als Luminescenzindikator

Ohne Zusammenfassung     

Lumineseenz-Titrationen II. Titrationen von Haloid-Ionen und anderen, ?hnlich wirkenden Ionen nebeneinander

Ohne Zusammenfassung     

Zur Fluorescenz des Nicotins

Ohne Zusammenfassung     

Investigation of Thyme (Thymus vulgaris L.) Essential Oil by Use of the BioArena System

JPC – Journal of Planar Chromatography – Modern TLC - The composition of the essential oil of Thymus vulgaris L. has been determined by GC-FID and GC-MS. Because separation of thymol,...     

Nachweis des Folliculins im filtrierten ultravioletten Licht

Zusammenfassung Es wird eine fluoreszenzanalytische Methode beschrieben, welche den Nachweis von 0,001 Folliculin in 1 ccm wäßriger oder alkoholischer Lösung ermöglicht. Mit gewissen Modifikationen ist diese Methode auch zum Nachweis des Folliculins in öligen Lösungen geeignet.

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Summary An analytical method based on fluorescence, is described. It is possible to detect, by means of this method, 0,001 of folliculine in 1 ccm. of aqueous or alcoholic solution. In a slightly modified form, this procedure can be applied for detecting folliculine in oily solutions.

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Résumé L'auteur décrit une méthode, permettant de déceler 0,001 de folliculine dans 1 ccm. de solution aqueuse ou alcoolique à l'aide de l'analyse de fluorescence. Avec certaines modifications, on peut aussi employer cette méthode pour le décèlement de la folliculine en solution huileuse.