Heat-shock proteins in sea urchin embryos. Transcriptional and posttranscriptional regulation

The production of heat-shock proteins in sea urchin embryos is accompanied by the appearance at the polysomal level of their relative mRNAs, as shown by their translation in a cell-free system; thus suggesting that the regulation of their production occurs at a transcriptional level. The mechanism for the inhibition of the bulk protein synthesis and for its reversal on the other hand should be looked for at a posttranscriptional level, since both these phenomena occur also in the presence of actinomycin D. The heat-shock proteins produced as early as at the mesenchyme blastula stage persist within the embryo at least till the pluteus stage.

[Extra-hospital emergencies. Proposal for a regional aid plan for Northern Lombardy and adjacent areas using helicopters]

An aid service based on the use of helicopters for Northern Lombardy and its adjacent areas is proposed. This would be based on the Varese Hospital and on existing heliports and airports in the area, this being one of Europe's most heavily populated and industrialised regions. The question of airborne aid is discussed, together with the solutions adopted in Italy, and those proposed and partly put into effect in Italy. An examination is also made of the factors in favour of the placement proposed; geographical features, road infrastructures, distances, prevailing weather conditions, and other points. The proposal is seen as a working hypothesis available for the authorities responsible under the current legislation, and as a model for similar investigations in other areas.

Inverse affects on thymidine incorporation in dissociated blastula cells of the sea urchin Paracentrotus lividus induced by butanol treatment and fab addition

When dissociated blastula cells of the sea urchin Paracentrotus lividus were prevented from aggregating by extracting them with 2.5% n-butanol in sea water, they became unable to incorporate labelled thymidine, like over-diluted dissociated cells. If, however, cells were prevented from aggregating by the addition of Fab against plasma membranes, thymidine incorporation was not blocked, but increased compared to that of spontaneously aggregating cells. At the same time amino acid incorporation also increased.

Synthesis of "heat shock" proteins in sea urchin embryos

Heating at 31 degrees C produces in sea urchin gastrulae a general and severe inhibition of the protein synthesis together with a marked increase in the rate of synthesis of one or very few classes of specific proteins.

Archenteron cells are responsible for the increase in ribosomal RNA synthesis in sea urchin gastrulae

Paracentrotus lividus embryos were continuously labeled with P32 from hatching blastula to pluteus. The archenteron cells were then separated from the rest of the embryo and the radioactivity accumulated into the ribosomal RNA of the two cell groups measured. The results clearly indicate that the bulk of ribosomal RNA is mainly if not entirely, synthesized in this time interval by the archenteron cells.

[The anesthesia outpatient department. A structure in keeping with the Health Service Reform]

Attention is drawn to the pressing need to establish out-patient departments for anaesthesia and anaesthesiological treatment within anaesthesia, resuscitation and intensive therapy services. In addition to offering specialist services, such as anaesthesiological therapy, and such services as may be in keeping with the local situation, such departments should be engaged in research, and towards the provision of preoperative anaesthesiological management prior to admission, on behalf of patients undergoing surgery of choice, so as to cut down the overlong period of preoperative stay. An assessment is made of the economic and social benefits of such departments, particularly in the light of the experience gained from similar structures that have long been in use in other countries.

Studies on the structure and possible function of the RNA "cap" in developing sea urchins

Paracentrotus lividus embryos at the hatching blastula stage very quickly incorporate radioactivity from labeled nucleosides (except uridine) or 32P- or methyl-labeled methionine into a portion of the RNA that has been identified as a "cap". The most probable sequence of this cap is m7G (5') ppp (5')mAmpCp. A very active "capping" and methylation of the "cap" of preexisting RNA molecules was shown to occur at the blastula stage.

The RNA of unfertilized sea urchin eggs is "capped"

It is shown that the RNA of unfertilized sea urchin eggs is active in stimulating protein synthesis in a wheat germ cell free system. This activity is not lowered by conditions that inhibit the methylation processes but is inhibited by a treatment that damages the "cap", A difference in activity in a wheat germ cell free system between the RNA of unfertilized eggs and the RNA from early embryos is described.

[Enflurane-pancuronium combination: real progress toward greater safe conditions in general anesthesia]

The literature data and personal experience with high - and very high - risk patients show that the association of enflurane as anaesthetic and pancuronium as muscle-relaxant constitutes a positive advance in balanced general anaesthesia. Cardiocirculatory depression is not encountered; if anything, there is an improvement of homeostatic conditions. This results in increased safety, even for patients regarded as inoperable. Confirmation of the reasons for associating these two drugs has certainly been obtained. The method cannot, however, be employed indiscriminately, but, at least in theory, should be avoided in patients with serious hypertension or a myocardium that is particularly sensitive to endogenic catecholamine incretion. In hypotension, on the other hand, cases of imminent or frank shock, or situations where surgery cannot be postponed, the association is, paradoxically, a true pharmacological "support", backed up, of course, by other usual procedures. This contradiction of modern views concerning the peripheral circulation is only apparent, since the duration of anaesthesia is reduced; main aim in this period is the maintenance of sufficient circulation to the more important organs. Comparison with associations combining d-Tubocurarine, halothane and methoxyfluorane is still an open question as far as objective assessment of their usefulness is concerned. There can be no doubt, however, that the association of enflurane and pancuronium has eliminated a large sector of contraindications in the field of general anaesthesia.