Visceral larva migrans: examinations by means of enzyme-linked immunosorbent assay of human sera for antibodies to excretory-secretory antigens of the second-stage larvae of Toxocara canis

An enzyme-linked immunosorbent assay is described for the detection of serum antibodies to visceral larva migrans (Toxocariasis). Excretory-secretory antigens of the second-stage larvae of Toxocara canis were used as antigen to coat the polystyrene plates. With sera from patients high antibody titers were observed in both ocular and visceral disorders. Cross-reactions due to other parasitic infections could be excluded, including other migrating larval infections such as ascariasis, trichinellosis, strongyloidiasis, filariasis, and anisakiasis. In a small seroepidemiologic survey of healthy primary schoolchildren, a remarkably high percentage (7.1) reacted positively to this method. These children showed eosinophilia as compared to the seronegative group. The data were compared with those observed in other countries and the results prompt reconsideration of the significance of T. canis for public health.     

High-resolution color video cytophotometry

Comparison was made between cytophotometric measurements obtained using two data acquisition systems, one a microphotometer and the other a rapid video camera system, to ascertain whether the degradation of data with the faster video acquisition system still results in recorded images of sufficient quality to permit computer discrimination between cells of very similar appearance. Normal-appearing intermediate cells from cases with normal cytology and those from patients with dysplasia or malignant disease, as well as the subvisual markers within these cells that have rendered them capable of cytophotometric discrimination, were used for the study. Comparison of the data recorded by the two systems indicates that the diagnostic information is preserved in the change-over to a full-field, video-rate scanning system, with differences in the data caused primarily by differences in the spectral response of the two systems. This was reflected in the substantial differences observed in the color-related features and the lesser differences seen in the textural features, while the morphometric features (outline and shape) were virtually unaffected. The differences were primarily expressed on a cell-to-cell basis; in sets of about 300 cells, which would be used in patient-to-patient comparisons, the feature values showed remarkable consistency between the two systems.     

Amiloride-inhibited Na+ uptake into toad bladder microsomes is Na+-H+ exchange

Amiloride-inhibited Na+ transport into toad urinary bladder microsomes is sensitive to a pH gradient across the vesicular membrane. The magnitude of the gradient was measured directly with acridine orange. Also Na+ could stimulate amiloride-sensitive proton efflux from the microsomes. These results indicated that the transport process was Na+-H+ exchange.     

The status of the otter (Lutra lutra) in the British Isles

National field surveys for otters were carried out between 1977 and 1981. The species is apparently absent from large areas of England, although healthy populations still occur in the south-west. In many other areas, populations are isolated and fragmented and there is some evidence for continuing declines. In Wales the otter is rare or absent from the south and parts of the north. Healthy populations are present in the Highland Region of Scotland, on the north and west coasts and in the islands but there is evidence of a decline in the south and east-central lowlands. Otters are widespread and common in Ireland which sustains the best of the known populations in Europe.
Pollution by pesticides probably caused the initial rapid decline of the species but habitat destruction is increasingly important and where habitat is poor, human disturbance assumes greater significance. There is no evidence of competition with mink. The otter is now a protected species but if it is to recover some of its former range, remaining habitat must be retained.
While otter populations have decreased over much of northern Europe, the animal survives, albeit somewhat precariously, in a few southern parts of the continent.     

Stimulation by epinephrine of adenyl cyclase activity, cyclic AMP formation, DNA synthesis and cell proliferation in populations of rat thymic lymphocytes

During the first ten minutes after the beginning of a continuous exposure of rat thymocyte populations (maintained in vitro) to epinephrine, there is an increase in the cellular concentration of cyclic AMP. The hormone also increases the activity of a crude preparation of the thymocyte's cyclic AMP-forming enzyme, adenyl cyclase. Between 30 and 45 minutes after the beginning of exposure to epinephrine, an additional part of the cell population begins to synthesize deoxyribonucleic acid (DNA). These changes are finally followed two to four hours later by an increase of the flow of cells into mitosis. Since cyclic AMP itself is known to stimulate both the initiation of DNA synthesis and thymocyte proliferation, and since the mitogenic action of epinephrine is shown to be potentiated by caffeine and inhibited by imidazole, it is concluded that the mitogenic action of this hormone is mediated by the cyclic nucleotide.