Uptake of ferritin from the medium byTokophrya infusionum

Summary Tokophrya infusionum, a suctorian, is deprived of a mouth opening. The uptake of ferritin from the medium is accomplished through pits, invaginations of the plasma membrane which are permanent structures. From the pits containing ferritin, flat vesicles are pinched off transporting the ferritin to the cytoplasm.Supported by grant AI-08989 US Public Health Service.The author acknowledges gratefully the excellent technical assistance of Mrs Sondra Lewengrub.     

Effect of catecholamines on ADP aggregation of rat platelets in vivo

Summary The influence of catecholamines on the platelet count was studied in an in vivo experimental model obtained with cannulation of the carotid and of the femoral vein. The i.v. infusion of epinephrine and l-norepinephrine induces a low drop in the platelet count and also potentiate aggregation by ADP.     

Macrocortin: a polypeptide causing the anti-phospholipase effect of glucocorticoids

Anti-inflammatory glucocorticoids inhibit prostaglandin (PG) biosynthesis by preventing arachidonic acid release from phospholipids rather than inhibiting the cyclooxygenase. As in other cells, this steroid action depends on receptor occupation and de novo protein/RNA biosynthesis. We have previously shown in guinea pig perfused lungs and rat peritoneal leukocytes that the effect of steroids in PG generation is mediated by an uncharacterized 'second messenger'. Now, we report that this factor (which we have named 'macrocortin') is an intracellular polypeptide whose release and synthesis are stimulated by steroids. Macrocortin derived from rat peritoneal leukocytes is very similar to that released from guinea pig lungs.     

Thiopyrimidines: Specific inhibitors of poliovirus induced early cell damages

Riassunto Contrariamente ad altri inibitori specifici dei poliovirus che prevengono RNA-sintesi virale ed effetto citopatologico, ma non hano effetto sui danni precoci che l'infezione induce nel metabolismo cellulare, un derivato tiopirimidinico è anche capace di impedire il blocco precocem virus indotto, delle proteino-sinsteis cellulari.

---

---

This work has been supported by the Consigiio Nazionale delle Ricerche, Rome (Italy).