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M Dolivo

Publications and source records attributed to M Dolivo.

At least 37 records · Page 2Linked to original sources

[Results of a comparative therapeutic trial of single-dose treatment of non-complicated acute male gonorrhea].

A single dose treatment trial with: spectinomycine 2 g, ampicilline + probenecide 3.5 g + 1 g, thiamphenicol 2.5 g, minocycline 300 mg was undertaken. Three teams were involved, epidemiologists clinicians, microbiologists, 636 patients were included, 483 resumed for control. A negative culture on the third day was considered a success. Failure rates were: spectinomycine 4%, ampicilline-probenecide 3%, thiamphenicol 4%, minocycline 3%. No significant difference was noted between the four rates. The delay of clinical cure was 1.98 days for spectinomycin, 1.87 days for ampicilline - probenecide, 2.16 days for thiamphenicol and 2.12 for minocycline without significant difference. When side effects were analysed, 10% of the patients reported asthenia without difference between the four treatments. Thiamphenicol is responsible for diarrhea 28%, P less than 0,01 minocycline more significantly responsible for guidiness 13%, P less than 0,001, and 18% treated by spectinomycine complained of pain at the time of injection. The antibiotics MIC's are studied. After the analysis of the results, the cost, and the resistances, one treatment was selected.

Ampicillin↗

Alteration of the electrophysiological activity in sympathetic ganglia infected with a neurotropic virus. I. Presynaptic origin of the spontaneous bioelectric activity.

The bioelectric activity of the rat superior cervical ganglion (SCG) infected with pseudorabies virus (PRV) was examined in vitro 30-38 h after inoculation. Simultaneous intra- and extracellular recordings on the internal (ICN) and external carotid nerves (ECN) revealed a synchronized spontaneous activity. This synchronization can be ascribed either to the functional organization of the ganglion or to the mechanism of initiation itself. In the infected ganglia two categories of cells were observed: cells displaying abnormal spontaneous discharges, and silent cells whose electrophysiological behavior was similar to control cells. Spontaneously active cells showed intermittent spiking and bursting activity. The discharge pattern was associated with the firing rate of the emitting cell: sporadically active cells emitted single spikes whereas highly active cells fired bursts of action potentials (APs). Long lasting intracellular recordings demonstrated that the cells undergo gradual changes evolving from sporadic on to high activity. Spontaneous APs usually rode on prepotentials similar to the excitatory postsynaptic potentials (EPSPs). A comparative study of spontaneous prepotentials and orthodromically evoked EPSPs in the same cell demonstrated that the spontaneous prepotentials are real synaptic potentials. No pace-maker potentials were observed. The passive and active electrical membrane properties of spontaneously active neurons were not different from those of silent cells or control cells impaled in uninfected ganglia. D-Tubocurarine abolished the spontaneous activity in the whole ganglion. Ortho- and antidromic electrical stimulations of suprathreshold intensity elicited an evoked response in neurons displaying spontaneous activity, followed by a delayed burst whose shape was similar to the spontaneous burst of the cell. Stimuli of subthreshold intensities induced this delayed burst independently from the evoked response. We conclude that the spontaneous bioelectrical activity is of presynaptic, but not necessarily of preganglionic origin. The possible existence of a cholinergic intraganglionic pathway revealed by the viral infection is discussed.

Action Potentials↗

[Progression of the rabies virus in the visual system of the rat].

The CVS rabies virus, inoculated in the anterior chamber of the eye, is transported from the retina to the central nervous system only along the accessory optic tract and invades transsynaptically its terminal nuclei. On the other hand the retino-geniculo-cortical system is affected much later. Thus the virus shows a special affinity for a well defined neuronal system and behaves as a precise tracer of its intracerebral connections.

Animals↗

Isolation and partial characterization of rat CNS axolemma enriched fractions.

Axolemma-enriched fractions were prepared from rat brain by osmotic shock of a purified preparation of myelinated axons and subsequent separation of myelin, two axolemma-enriched fractions and myelin-free axons by density gradient centrifugation. Compared with the starting whole homogenate, the fractions were enriched in specific activity of Na+K+ ATPase, acetylcholinesterase, 5'nucleotidase as well as 2',3'-cyclic nucleotide 3'phosphohydrolase. Compared with myelin, the axolemmal fractions are greatly enriched in high molecular weight proteins. The 1.0/1.2 fraction has a predominant peak of fucose-labeled glycoprotein with a molecular weight between that of the myelin associated glycoprotein and the Wolfgram protein which is absent from the myelin glycoprotein profile. Polyacrylamide gel electrophoresis showed that the protein profile of myelin isolated by this procedure was similar to that of myelin isolated by other procedures and that the myelin specific basic and proteolipid proteins were virtually absent in the axolemma-enriched fractions. Both axolemma fractions were enriched in higher MW proteins, some of which resembled proteins in the myelin protein profile. Both axolemma-enriched fractions specifically bind between 2 and 3 pmoles of [3H]tetrodotoxin per mg protein. The axolemma-enriched fractions incorporated [3H]leucine and [14C]fucose exclusively into high molecular weight proteins and glycoproteins. In contrast myelin concomitantly isolated with the axolemma-enriched fractions had a significant amount of [3H]leucine labeled protein in myelin proteolipid and basic proteins. In addition to the myelin associated g-ycoprotein the [14C]fucose labeled a glycoprotein of slightly larger apparent molecular weight than proteolipid protein was found in the myelin fraction while the comparable labeled glycoprotein was absent in the axolemma-enriched fractions. The possible extent of contamination of these fractions by myelin or myelin subfractions and relationship of these axolemma-enriched fractions to other axolemma preparations are discussed.

2',3'-Cyclic-Nucleotide Phosphodiesterases↗

Ultrastructure and function in sympathetic ganglia isolated from rats infected with pseudorabies virus.

(1) After inoculation of the pseudorabies virus in the anterior chamber of the eye of the rat, virions can be found only in the neurons of the superior cervical sympathetic ganglion and in the sensory ganglion of the fifth nerve on the inoculated side. Other nervous structures--central or peripheral--are not infected. (2) It is shown that the retrograde axonal flow carries the virus from the eye to the sympathetic neurons. (3) The ultrastructure of the infected neuron has been studied at various intervals after inoculation and at different stages of the viral replication. (4) Excised infected ganglia in vitro show a spontaneous electrophysiological activity that can be recorded on both the post- and preganglionic nerve. Such an activity has never been seen in normal excised ganglion of rat. (5) The shape and frequency of the electrophysiological discharges recorded on the postganglionic nerve have been analyzed at various intervals after inoculation. (6) Correlations established between the ultrastructure, the effect of various drugs and the electrophysiological activity permit the proposal of various hypothesis about the abnormal activity of the infected neurons.

Action Potentials↗