Cocultivation of phytopathogenic Fusarium and Alternaria strains affects fungal growth and mycotoxin production.

AIMS: A laboratory study was conducted to evaluate the influence of cocultivation of toxigenic Fusarium (F.) and Alternaria (A.) fungi with respect to growth and mycotoxin production. METHODS AND RESULTS: Fusarium culmorum Fc13, Fusarium graminearum Fg23 and two Alternaria tenuissima isolates (At18 and At220) were simultaneously or consecutively co-incubated on wheat kernels in an in vitro test system. Fungal biomass was quantified by determining ergosterol content. Three Fusarium toxins (DON, NIV and ZON) and three Alternaria toxins (AOH, AME and ALT) were analysed by a newly developed HPLC/MS/MS method. In simultaneous cocultures, the fungal biomass was enhanced up to 460% compared with individual cultures; Alternaria toxins were considerably depressed down to <5%. Combining At18 and At220 with Fg23 inhibited the toxin production of both fungal partners. In contrast, Fc13 increased its DON and ZON production in competitive interaction with both A. strains. CONCLUSIONS: The interfungal competitive effects aid the understanding of the processes of competition of both fungi in natural environments and the involvement of mycotoxins as antifungal factors. SIGNIFICANCE AND IMPACT OF STUDY: Cocultivation significantly affects fungal growth and mycotoxin production of phytopathogenic Alternaria and Fusarium strains. The impact of mycotoxins on the interfungal competition is highlighted.

Determination of fumonisins B1 and B2 in corn by LC/MS with immunoaffinity column cleanup: interlaboratory study.

An interlaboratory validation study was conducted to establish the method performance characteristics of an immunoaffinity column (IAC) cleanup procedure followed by LC/MS for the determination of fumonisins B1 (FB1) and B2 (FB2) and combined FB1 + FB2 in corn. The test portion is extracted with acetonitrile-methanol-water (25 + 25 + 50). The extract is filtered, diluted with phosphate-buffered saline solution, and applied to an IAC. FB1 and FB2 are removed with methanol, followed by water, then directly determined by RPLC with MS detection using selected-ion monitoring of two characteristic ions in each case. Naturally contaminated corn samples were milled to a fine powder and mixed to produce three samples with target levels of combined FB1 + FB2 ranging from 350 to 4000 microg/kg. Of 15 initially participating laboratories, two failed to report results and another did not follow the prescribed method. Thus, valid results were obtained from 12 participants located in 11 countries. Statistical analysis of the results produced RSDr values of 4.6-11.9, 1.9-12.6, and 1.4-11.5% for FB1, FB2, and combined FB1 + FB2, respectively; the corresponding RSDR values were 19.8-23.8, 18.2-25.5, and 18.8-23.2%. The three concentration levels of combined FB1 + FB2 were 534, 1194, and 1954 microg/kg. HorRat values for r and R were all < 2.0, indicating that the method is suitable as a regulatory method for the enforcement of European Union limits for fumonisins in corn.

[The effect of positive pressure breathing on the correlation between pulmonary wedge and left atrial pressure in hyper-, normo- and hypovolaemic dogs (author's transl)]. / Tierexperimentelle Untersuchungen über den Einfluss des endexspiratorischen Druckes auf die Beziehung zwischen linkem Vorhofdruck und pulmonal-arteriellem Wedge-Druck in Abhängigkeit vom Füllungszustand des Gefässsystems.

The effect of altering end-expiratory inflation pressure from 0 to 20 cm H2O in relation to the pulmonary capillary wedge-pressure (PCWP) and the left atrial pressure (LAP) were studied in dogs, whose blood volume was varied by infusion of dextran or by haemorrhage. In the hyper- and normovolaemic state there was a good correlation between PCWP and LAP up to an end-expiratory pressure of 15 cm H2O. In the hypovolaemic dogs this close agreement existed only up to levels of PEEP 10 cm H2O. Above this end-expiratory pressure pulmonary capillary wedge-pressure increased more than left atrial pressure.

[The computerized anaesthetic record of the 'Universitätsklinik Köln' (author's transl)]. / Das datenverarbeitungsgerechte Anaesthesie-Protokoll der Kölner Universitätskliniken.

Some of the main arguments are presented which led us to develop our present anaesthetic record. This record system and a part of its voluminous code is described. The new version provides for the documentation of arbitrarily complicated status, which are due to the preoperative condition of the patient. Furthermore, the course of aneaesthesia and its effects upon the patient can be numerically recorded in a detailed fashion. The punching is affected by a small rate of error only.

[Experimental studies about the origin of the "wedge-blood" in partially atelectatic lungs of mongrel dogs (author's transl)]. / Untersuchungen zur Herkunft des Wedge-Blutes teilweise atelektatischer Hundelungen.

We measured in 8 experimental studies the oxygen and carbon dioxide partial pressure in systemic arterial, mixed venous and wedge-blood. The results were: 1. In healthy mongrel dogs with controlled intermittent and continuous positive pressure ventilation (FIO2 0,21 and 1,0) paO2 greater than pwO2 greater than pvO2 and pwCO2 less than paCO2 less than pvCO2. 2. During experimentally produced left-sided atelectasis of the lung and positioning of the catheter in the pulmonary artery a) in the ventilated lung we found pwO2 greater than paO2 greater than pvO2 and pwCO2 less than paCO2 less than pvCO2 b) in the atelectatic lung we found paO2 greater than pwO2 greater than pvO2 and paCO2 less than pwCO2 less than pvCO2. According to these findings the sample of highly saturated mixed venous blood from a catheter in the pulmonary artery should be a hint that pulmonary capillary blood is mixed with central venous blood.

[Cardiovascular effects produced by prophylactic digitalization during introduction of anaesthesia (author's transl)]. / Auswirkungen der präoperativen Glykosidprophylaxe auf das Kreislaufverhalten während der Anästhesieeinleitung.

The narrow field of non-controversial indications concerning the application of digitalis glycosides is pointed out. Problems of routine digitalization of older patients not suffering from cardiac insuffiency are discussed with special regard to preparing them for operations. Up to now, from the viewpoint of anaesthesiologists no benefits of prophylactic digitalization have been found. In a retrospective computerized study, clinical hemodynamic parameters during introduction of anaesthesia have been investigated by means of anaesthetic data recorded during three years. Nondigitalized patients older than fifty years showed satisfactory cardiac functions, whereas prophylactically digitalized patients--compared with the control group--have been treated with plasma expanders earlier and at a double rate. Furthermore, higher heart frequencies and greater tendency to arrythmias were observed. Consequently, prophylactic digitalization cannot be recommended in general.

[Anaesthetic problems during resection of the carina (author's transl)]. / Anaesthesiologische Probleme bei der Bifurkationsresektion der Trachea.

Benigne tracheo-bronchial constriction is an infrequent indications for resection of the bifurcation of the trachea. In former times resection and reconstruction of the bifurcation have been performed using extracorporal oxygenation. Nowadays, the method of separate ventilation of both lungs is used more frequently. Pathophysiological variations should be taken into consideration, which may occur during interruption of the ventilation of one side of lung caused by operating procedures. Rapidly developing atelectasis of the non-ventilated but perfused lung endangers the patient, as a result of an increased intrapulmonary right-to-left-shunt. Hypoxaemia can be prevented by temporary occlusion of the pulmonary artery of the nonventilated lung. This procedure is to be recommended in view of the fact that there is no prompt constriction of the vessels. Investigations with dogs show that a slightly developing accommodation of the perfusion can be disturbed by variations of cardiac output or mean pressure of ventilation.