Difference in electrical activity during wakefulness and the phase of ‘sleep with muscular twitches’ as recorded from the cortex of the marsupialDidelphis azarae (South American opossum)

Resumen Se ha observado una neta diferencia entre los registros electroencefalográficos de la vigilia y la fase de « Sueño con sacudidas musculares » del MarsupialDidelphis azarae según sea la posición de los electrodos sobre la corteza cerebral.     

Distribution of inulin space in the rabbit thoracic aorta

Zusammenfassung Die ganze Länge und Dicke des extrazellulären Raumes der thorakalen Kaninchenaorta wurde gemessen. Der Raum ist unverändert die ganze Länge des Blutgefässes hindurch und entspricht 0,59 ml/g 0,39 ml/g für die Adventitia und die Media. In jeder dieser Tunicae ist der Raum durch ihre ganze Dicke gleichmässig verteilt.

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Supported by grants from The American Medical Association Education and Research Foundation, U.S. Public Health Service (HE-08359) and the Los Angeles County Heart Association (408 IG).     

On the synthesis of poliovirus RNA at supraoptimal temperatures

Riassunto La scarsa incorporazione di precursori dello ARN in cellule infette da poliovirus ed incubate a 41,5°C è dovuta ad una inibizione della sintesi dello ARN virale più che non ad una sua digestione ad opera di nucleasi.

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Work supported by a Grant of Consiglio Nazionale delle Ricerche, Rome.     

Biological and biomedical implications of the co-evolution of pathogens and their hosts

Co-evolution between host and pathogen is, in principle, a powerful determinant of the biology and genetics of infection and disease. Yet co-evolution has proven difficult to demonstrate rigorously in practice, and co-evolutionary thinking is only just beginning to inform medical or veterinary research in any meaningful way, even though it can have a major influence on how genetic variation in biomedically important traits is interpreted. Improving our understanding of the biomedical significance of co-evolution will require changing the way in which we look for it, complementing the phenomenological approach traditionally favored by evolutionary biologists with the exploitation of the extensive data becoming available on the molecular biology and molecular genetics of host-pathogen interactions.