The diagnosis of antileptospiral antibodies in human subjects by solid-phase immunoenzyme analysis

The possibility of using the enzyme-linked immunosorbent assay (ELISA) for the diagnosis of leptospirosis has been shown. This method has proved to be more simple and sensitive than the leptospiral microagglutination and lysis test. The data on obtaining genus-specific leptospiral antigens are presented. As revealed in this study, the antigens obtained by the complex treatment of microbial cells with ultrasound and detergents show the maximum activity in ELISA. The optimum parameters of the ELISA system for the diagnosis of leptospirosis have been established.     

Photoelectric signals from dried oriented purple membranes of Halobacterium halobium

In dried oriented samples of purple membrane isolated from Halobacterium halobium, the photoelectric activity decreases and the light adaptation vanishes when the water content of the sample is lowered. In the photocycle the first steps of the proton movement were accelerated with decreasing humidity, while the last steps of the photocycle could not be observed. From the analysis of the photoelectric signal we conclude that at low humidities the protons move forward in the L decay and return to their original place during M decay.     

Value of prednimustine in treating non Hodgkin's lymphomas of favourable histological type

24 patients with non-Hodgkin's lymphomas of low-grade malignancy (stage III and IV) were treated either with a single drug (prednimustine) or with combination chemotherapy (cyclophosphamide, vincristine and prednisone). Response to therapy was similar in both groups. Prednimustine induced complete remission in 6 from 13 patients, while in that group treated with combination chemotherapy a complete remission was recorded in 4 from 11 patients. Both regimens were well tolerated. Therapy with prednimustin has an advantage in oral administration enabling it to be used in out-patient practice.     

Have the bloody cells gone to our heads?

Recent studies have shown that cells expressing neuronal antigens can be derived from a bone marrow transplant. A new report lends support to and extends these previous results by presenting compelling morphological evidence for the generation and integration of highly differentiated bone marrow-derived neurons.     

Histochemical study of calcium on T-tubule membranes and in the sarcoplasmic reticulum, in frog twitch muscle fibres at rest and during activity

The trigger calcium hypothesis of signal transmission between T-tubules and terminal cisternae (TC) of the sarcoplasmic reticulum (SR) in twitch muscle fibres implies the presence of calcium along T-tubule membranes at rest and its release upon excitation. To test this hypothesis, calcium was immobilised using a fixing and precipitating solution of glutaraldehyde in phosphate buffer at pH 8.0 and the calcium was substituted for by lead. Simultaneous tension recordings revealed the occurrence of contractions or a burst of twitches upon perfusion with the fixative. Procaine or tetrodotoxin (TTX) was used to inhibit this activity. In fibres without fixative-induced activity, precipitates were observed along T-tubules and in adjoining parts of TC. In activated fibres, tubular and TC precipitates were absent. These results are consistent with the trigger calcium hypothesis. In fibres activated by depolarisation, calcium returned to TC after passing successively through different parts of the SR.     

The excavations of La Isabela,the first European city of the New World

In the present note the author presents history of the discovery and of the status of the excavation of the site La Isabela, the first settlement planned by Columbus in the New World during his second trip to America in the summer of 1493.