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Four independent molecular methods were used to characterize the Salmonella enterica subsp. enterica serovar choleraesuis live vaccine strains SC-54 and Suisaloral and to differentiate them from S. choleraesuis field isolates. Plasmid analysis revealed the presence of seven plasmid profiles. A virulence plasmid of 52-kbp was identified by hybridization with an spvB-spvC gene probe in each of the S. choleraesuis field isolates and in the Suisaloral vaccine strain, but not in the SC-54 vaccine strain. Ribotyping, performed with a gene probe that recognized 23S, 16S, and 5S rRNA genes, resulted in three closely related hybridization patterns. IS200 elements were not detected in the field isolates or in the two S. choleraesuis live vaccine strains. Macrorestriction analysis with the enzymes XbaI, SpeI, NotI, and SfiI differentiated the 29 S. choleraesuis strains included in this study into 10, 13, 8, and 13 different fragment patterns, respectively. While the Suisaloral vaccine strain showed a unique XbaI macrorestriction pattern, the fragment patterns of the SC-54 strain obtained with the different enzymes were shared by 2 to 18 S. choleraesuis field strains. A combination of plasmid analysis and macrorestriction analysis proved to be most suitable for the molecular typing of S. choleraesuis and the differentiation of both live vaccine strains from field isolates of this serovar.

Summary Carotid surgery is frequently associated with postoperative blood pressure alterations. The role of baroreceptors with regard to these alterations was assessed in 50 patients by determining the pre- and postoperative mechanoreceptor sensitivity after Valsalva maneuver and intravenous injections of angiotensin and nitroglycerine as described by Smyth, Sleight and Pickering. In addition, blood pressure was monitored perioperatively and renin and aldosterone levels were measured. In patients with arterial hypertension a postoperative increase of receptor reactivity can be seen necessitating a reduction of antihypertensive therapy in more than 50% of cases. In normotensive patients no uniform response can be observed. A possible explanation for this effect might be the local increase of pressure in the operated vascular segment. The postoperative reintegration of receptor areas which had been adjusted to a reduced pressure level might induce a more sensitive response than can be seen for the remaining receptors, which usually are less responsive in hypertensive patients.

A total of 28 unrelated isolates of the Salmonella enterica subsp. enterica serovar dublin (S. dublin) collected during a 6-year period, as well as four samples of the S. dublin live vaccine strain Bovisaloral and its prototype strain S. dublin 442/039, were investigated by different molecular typing methods for the following reasons: (i) to find the most discriminatory method for the epidemiological typing of isolates belonging to this Salmonella serovar and (ii) to evaluate these methods for their capacity to discriminate among the live vaccine strain Bovisaloral, its prototype strain S. dublin 442/039, and field isolates of the serovar dublin. Five different plasmid profiles were observed; a virulence plasmid of 76 kbp as identified by hybridization with an spvB-spvC gene probe was present in all isolates. The detection of 16S rRNA genes and that of IS200 elements proved to be unsuitable for the epidemiological typing of S. dublin; only one hybridization pattern could be observed with each of these methods. The results obtained from macrorestriction analysis strongly depended on the choice of restriction enzyme. While the enzyme NotI yielded the lowest discriminatory index among all enzymes tested, it was the only enzyme that allowed discrimination between the Bovisaloral vaccine strain and its prototype strain. In contrast to the enzymes XbaI and SpeI, which only differentiated among the S. dublin field isolates, XhoI as well as AvrII also produced restriction fragment patterns of the Bovisaloral strain and of its prototype strain that were not shared by any of the S. dublin field isolates. Macrorestriction analysis proved to be the most discriminatory method not only for the epidemiological typing of S. dublin field isolates but also for the identification of the S. dublin live vaccine strain Bovisaloral.

1. Plasma levels of endothelin were measured in 30 patients with chronic renal failure, 32 patients on chronic haemodialysis treatment and 25 renal graft recipients with stable renal graft function. 2. In patients with chronic renal failure as well as in patients on regular haemodialysis treatment, mean plasma levels of endothelin were significantly increased (4.59 ± 2.09 pg/ml, 10.08 ± 3.12 pg/ml, respectively) when compared with normal subjects (1.88 ± 0.6 pg/ml, P <0.01, P <0.001, respectively). 3. In the group with chronic renal failure a positive correlation between the plasma level of endothelin and the plasma concentration of creatinine was observed (P<0.003). 4. Renal graft recipients on cyclosporin A with stable renal graft function had a normal plasma level of endothelin suggesting that cyclosporin A nephrotoxicity is not mediated by endothelin. 5. Hypertensive patients with chronic renal failure or on regular haemodialysis and hypertensive renal graft recipients did not differ from the corresponding normotensive population with regard to the plasma level of endothelin, demonstrating that an increased plasma level of endothelin does not play a major role in the pathogenesis of renal hypertension.