[Familial investigations of carriers of Rh 33]. / Familienuntersuchung einer Trägerin von Rh 33.

The erythrocytes of a blood donor (P) showed an unusual pattern with anti-D sera: no agglutination with incomplete sera, and a strong agglutination with 2 out of 5 complete, monoclonal sera. These findings suggested the presence of an Rh 33, which was then confirmed in two external laboratories as the genotyp R0Har. Using anti-e sera, the titer scores of the cells of P were comparable with those of Ee cells but were only half as high as the scores of ee cells. This is consistent with a weak e in R0Har. The red cells of the donor's daughter (T) gave a positive reaction with all anti-D sera, but we observed no or only weak agglutination with several anti-e sera. It is very probable that T is also carrier of R0Har.

Isoenzyme patterns of Entamoeba histolytica isolated from homosexual men.

This is a preliminary report on isoenzyme patterns of Entamoeba histolytica which were examined by starch gel electrophoresis. By this means the amoebae isolated from 17 asymptomatic male homosexuals were characterized into zymodemes. No amoebic strain isolated corresponded to a pathogenic zymodeme.

[Pathogenicity of Acanthamoeba isolated from water]. / Versuche über die Pathogenität von aus Gewässern isolierten Acanthamöben.

Two Acanthamoeba strains were isolated from rivers in Berlin by intranasal inoculation into mice. No clinical or pathological symptoms could be observed in the animals. The intention of this study was to initiate and to increase the pathogenicity of these amoebae. The two strains were passaged in mice as well as in liquid medium followed by inoculation into mice. The pathogenicity was measured by the rate of lethality. The first cases of death were found after the 10th passage in those mice which had been infected with the amoebae only passaged in animals. Acanthamoebae could be isolated from brains and lungs, but pathological changes were found only in lungs. After the 11th and 12th animal passage, respectively, the amoebae were only cultivated in vitro for 15 weeks followed by another series of animal passages. Here, first cases of death were recorded after the 5th and 3rd inoculation into mice, respectively. No animals died having been infected with amoebae only maintained in vitro. A third experiment with animal passaged strains showed that mice died even up to the 6th week p.i. and that amoebae could be re-isolated until the 7th week i.p. The results are discussed in view of a possible selection of pathogenic Acanthamoeba strains by fast passages from man to man.

[Examination of thermally polluted water for free living amoebae and testing for their possible pathogenic properties]. / Untersuchungen von künstlich erwärmten Gewässern auf freilebende Amöben und deren Prüfung auf mögliche pathogene Eigenschaften.

Water and mud samples were collected from canals and rivers which were adjacent to outlets discharging warm water of 3 power plants in Berlin. Downstream samples from 1 bathing resort were also collected. Free living amoebae were isolated from 138 water and 69 mud samples. From these respectively 156 and 73 strains could be cultured and were administered intranasally to mice for pathogenicity tests. Two Acanthamoeba strains from water and 7 from mud could be reisolated from mouse brain and or lungs, although no pathological disorders could be observed. Five Naegleria strains were negative in mouse inoculation tests. Four Acanthamoeba strains which were positive in mice were cultured at + 45 degrees C; no cytopathogenic effects were observed in tissue cultures. Acanthamoeba infective for mice could also be isolated from samples at low water temperatures. Further investigations have to show, whether changes in virulence of amoebic strains are of significance and therefore for epidemiology and pathogenicity in man.