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In an experimental and then clinical investigation, the intention has been to demonstrate that tissue adhesive (Histoacryl Braun) is a useful safety factor in a wide variety of difficult intestinal sutures, in both emergency surgery and in that of choice. Experiments were carried out on about a hundred rabbits which received colic anastomosis, after clean, complete section, anastomosis of the viscera, with four cardinal sutures in 000 silk and the remaining suture of a diameter of about 3 cm with adhesive. This stage having been surmounted with excellent results, work continued with the experiment in emergency surgery and surgery of choice, on the basis of the criterion of greater safety as a complement of the traditional high dehiscence risk suture technique. The clinical results obtained thus far have been encouraging enough to suggest its experiments.

The effects of the following vasoactive drugs: Bencyclan fumarate, Cetiedil citrate, Cinepazide maleate, Dihydroergocristine methane sulphonate, Nafthydrofuril acid oxalate, Papaverine hydrochloride, Piribedil monomethane sulphonate, Raubasine, Thymoxamine hydrochloride and Xanthinol nicotinate, in concentrations ranging between 0.001 - 2 mM, were tested on the compound action potentials led off from human isolated sympathetic ganglions. The experiments, carried out on 50 isolated lumbar ganglion preparations removed from 23 subjects with arteriopathy of the limbs, indicated that all the drugs are able to impair the synaptic transmission, although at different concentrations. These findings are in favour of the hypothesis that the vasodilatatory effects observed after therapeutic treatment of patients with vasoactive drugs are partially produced by the vasodilatation following the depression of the sympathetic nervous transmission.

L-glutamate (Glu) has at least two sites of action in the frog semicircular canal: the hair cell (presynaptic) and the primary afferent nerve fibres (postsynaptic). Glu's action on the hair cell results in an increased release of the natural transmitter which is responsible for a substantial increase in the frequency of firing in primary afferents. The presynaptic action of Glu is antagonized by D-alpha-aminoadipate (D alpha AA). Glu produces a long-lasting depolarization on the afferent nerve fibres which does not by itself elicit any afferent discharge of impulses when the release of the natural transmitter is prevented. Glu-induced nerve depolarization is only partially antagonized by D alpha AA. The difficulty of reconciling some of the observations made of the effects of Glu in semicircular canals with its presumed role as an afferent transmitter in this organ is discussed, but this role is not definitely rejected.

An analysis of the EPSPs recorded intracellularly from single fibres of the VIII nerve revealed that the resting release of chemical transmitter at the cyto-neural junctions in the sensory organ of frog semicircular canals displays a rather low temperature dependence. This provides evidence that, in labyrinthine receptors, the resting activity is actually "evoked" in nature. A comparison between the discharge of EPSPs and propagated spikes in the VIII nerve fibres has shown that the "encoders" of primary vestibular neurones are highly sensitive to temperature changes and irreversibly damaged at temperatures exceeding 28 degrees C.

An appraisal is made of the methods adopted by surgeons from different schools in the surgical management of perforated diverticulitis of the colon. For this purpose, an examination is made of 27 cases treated over the course of 5 years at the First-Aid Section of the Genoa General Hospital. While approval is expressed of an eclectic approach to individual cases in the light of the patient's condition, it is felt that the long-established tactic of exteriorisation and resection according to Mikulicz is still perfectly sound.

The percutaneous absorption of diclofenac diethylammonium 1.16% (w/w) in a combination of emulsion cream and gel (Voltaren Emulgel) and of diclofenac sodium 1% (w/w) in a cream formulation (Voltaren cream) was investigated in guinea-pig, rabbit and man. The percutaneous absorption of diclofenac sodium in guinea-pig was 3 to 6% of the dose when the cream formulation in doses of 320, 100 or 40 mg was applied on 10 cm2 of occluded skin and left in place for 6 h. The transdermal delivery of 14C-labelled diclofenac yielded plateau plasma concentrations of radiotracer from 1.5 h after application until removal of the residual cream. Subsequently the steady state drug depots in the skin and muscle tissue were depleted promptly. During daily administration the steady state levels in the muscle tissue in proximity to the application site were about 3 times higher than in distant muscle tissue. By topical application on knee joints of rabbits diclofenac penetrated into the patellar ligament, the adipose corpus and the synovial fluid. In man the percutaneous absorption was 6% of the dose when the Emulgel formulation was spread by 5 mg/cm2 and left for 12 h on non-occluded skin. The pattern of metabolites of diclofenac in human urine was the same after topical and oral administration. In man, upon daily topical administration of 3 times 2.5 g cream formulation (10 mg/cm2) the diclofenac steady state plasma levels were 20 to 40 nmol/l.(ABSTRACT TRUNCATED AT 250 WORDS)

A method has been developed for the removal, preservation and electrophysiological study 'in vitro' of sympathetic lumbar chains (L1-L3) from subjects undergoing lumbar ganglionectomy in the treatment of peripheral vascular diseases. Extracellular recordings from interganglionic trunks, and intracellular recordings from single sympathetic neurons, were performed. The extracellular experiments substantiated the concept, hitherto deduced from animal experiments, that the preganglionic fibres in the sympathetic lumbar chain are mainly of a descending nature. In fact, stimulation of the interganglionic trunk cranial to ganglia is always much more effective in driving ganglion neurons to fire than stimulation of the interganglionic trunk caudal to ganglia. The intracellular experiments produced a good definition of the main electrical characteristics of human sympathetic neurons. The results can be summarized as follows: the resting membrane potential ranged from 50 to 75 mV (63.4 +/- 9.2 mV; 21 neurons); action potential amplitude from 62 to 93 mV (74.3 +/- 8.1 mV; 27 neurons); membrane input resistance was 42.3 +/- 12.6 m omega (8 neurons) and total membrane capacitance 83.7 +/- 15.3 pF (8 neurons).

The functional organization of the efferent vestibular system (EVS) was studied in the isolated frog labyrinth. To ascertain whether, besides the efferent branching fibres that innervate several end-organs, the EVS is also endowed with efferent non-branching axons which might control a given population of sensory units in each end-organ, the 8th nerve and one of its branchlets were electrically stimulated while recordings of the spontaneous activity arising from the different sensors were made by impaling single afferent axons in all the 8th nerve branchlets. The results demonstrated that the vast majority of the sensory units whose activity was modified by stimulating the whole 8th nerve was also affected by stimulating an 8th nerve branchlet. These findings therefore rule out the possibility that the EVS is endowed with projective fibres and strengthen the view that the EVS is a highly divergent system with collaterals arising from single parent axons that innervate several end-organs. These experiments have also shown that the percentage of sensory units which are actually controlled by the EVS varies amongst the different labyrinthine organs. It is maximal in the sacculus (ca. 90%), somewhat lower in canal organs (ca. 80%) and the utriculus (ca. 70%) and considerably lower in the lagena (ca. 50%). This EVS arrangement therefore might allow information arising from some organs to be modified more extensively than that from others.

The temperature dependence of conversion processes in the sensory organ of frog semicircular canals has been tested in the range 0-28 degrees C by recording the ampullar (Adc) and nerve (Ndc) slow potentials as well as the afferent discharge of impulses (Nfr) in the VIII nerve fibres. The results have shown that Adc is scarcely affected by temperature changes (Q10 less than 2) thus suggesting that stimulus conversion in labyrinthine cells does not imply chemical processes but mainly potassium conductance changes at their apical membrane. By converse, postsynaptic potentials and propagated spikes are markedly reduced at low temperatures (Q10 2.8 and 7 respectively) and only slightly increased between 20 and 28 degrees C. These observations are interpreted by considering the chemical nature of the processes which are involved. The temperature dependence in labyrinthine receptor activation is discussed in the view of its physiological meaning.

The effect of rapid changes in K+ concentration (from 0 up to 5 mM) in the perilymphatic fluid was tested on ampullar receptor activity in isolated semicircular canals of the frog. The effects of the different K-concentrations were evaluated by recording both the transepithelium potentials (Adc) and the postsynaptic potentials (EPSPs and spikes discharge) led off from the ampullar nerve. The results have clearly demonstrated that crista ampullaris sensory cells are extremely sensitive to K-changes (+/- 0.25 mM). In fact both transepithelial potentials and discharge activity (EPSPs and propagated spikes) of first order vestibular neurones may be decreased or increased by decreasing or increasing the K-concentration in the outer fluid. The possible mechanism of action of K+ on ampullar receptors is discussed.

Glutamate (Glu) has at least two sites of action in the frog semicircular canal: the hair cell (presynaptic) and the primary afferent nerve fibres (postsynaptic). Glu's action on the hair cell results in an increased release of the natural transmitter which is responsible for a substantial increase in the frequency of firing in primary afferents. Glu produces a long-lasting depolarization in the afferent nerve fibres which does not by itself elicit any afferent discharge of impulses when the release of the natural transmitter is prevented. The difficulty of reconciling some of the observations made of the effects of Glu in semicircular canals with its presumed role as an afferent transmitter in this organ is discussed.