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A birdcage resonant helicon antenna is designed, mounted, and tested in the toroidal device TORPEX. The birdcage resonant antenna is an alternative to the usual Boswell or half-helical antenna designs commonly used for ∼10 cm diameter helicon sources in low temperature plasma devices. The main advantage of the birdcage antenna lies in its resonant nature, which makes it easily operational even at large scales, an appealing feature for the TORPEX device whose poloidal cross section is 40 cm in diameter. With this antenna, helicon waves are shown to be launched and sustained throughout the whole torus of TORPEX. The helicon waves can be launched at low power on a pre-existing magnetron-generated plasma with little effect on the density profiles. The birdcage antenna can also be used alone to produce plasma, which removes the constraint of a narrow range of applied magnetic fields required by the magnetron, opening the way to a new range of studies on TORPEX with the external magnetic field as a control parameter., (© 2024 Author(s). Published under an exclusive license by AIP Publishing.)

Following a screening program for orally active antithrombotic drugs, it was found that a series of thioxyloside compounds presented with good venous antithrombotic properties. Of more than 500 compounds, LF 09-0055, LF 04-0212, and LF 05-0030 were the most active at inhibiting venous thrombus formation in the rat and rabbit Wessler model after intravenous and oral dosing. LF 05-0030 showed the greatest activity with an ED80 value of 6 mg/kg on oral administration in rats. This activity was maintained in several different models of venous thrombosis and shown to be devoid of anticoagulant effects or hemorrhage. Kinetic studies have demonstrated that maximal levels of activity, following either intravenous or oral dosing, occurred between 2 and 4 hours after administration. This may reflect the type of mechanism involved, since it has been well documented in the literature that xylosides are capable of initiating glycosaminoglycan (GAG) synthesis. Moreover, in vitro galactosyltransferase 1 (the second enzyme involved in GAG polymerization) enzymic assays showed that these thioxyloside derivatives were good acceptors for galactose transfer and therefore at initiating GAG formation. Further in vivo experimentation demonstrated that after treatment by these molecules an important elevation in circulating GAG occurred, with LF 05-0030 presenting the greatest activity, being five times higher than control levels. In addition it was found that dermatan sulfate levels, expressed as antithrombin activity by heparin cofactor II, were significantly increased over control values. As such, this dermatan sulfate moiety is believed to support the antithrombotic activity observed. Studies are underway to investigate the activity of these interesting molecules in atherosclerosis and other vessel wall diseases.

1) Glycopeptides were prepared by pronase digestion of the urea extract of dermis of two isogenic mouse strains C3H/He and C57BL/6. 2) The major glycopeptide fractions from both strains contain, glucosamine, galactose, mannose, fucose and sialic acid. 3) The sugar composition, the behaviour on gel filtration and yields of the glycopeptides with identical electrophoretic mobilities, isolated from the two strains, were identical.

Blood serum of severely burned patients contains several substances which are not present in normal sera. One of these substances, a small protein of an approximate molecular weight of 12 to 14,000 daltons displayed a toxic action on the circulatory system. This cardiotoxic factor was obtained in a purified form by alcohol precipitation followed by gel filtration and carboxymethyl cellulose chromatography. The purified preparation seems to be a low molecular weight protein of about 8000 daltons. The biological effects of this substance consist essentially of alterations of the ECG pattern, indicating decreased cardiac output and ischaemia of the cardial muscle. The blood pressure decreases and respiratory function is also altered. The presence of such a toxic factor in sufficient concentration in the blood serum may explain the cardiovascular complications observed in some burned patients.

The presence of antibodies against bovine herpesvirus 1 (BHV-1), bovid herpesvirus 6 (BHV-6), herpesvirus of Cervidae type 1 (HVC-1), reindeer herpesvirus, bovine herpesvirus 2 (BHV-2) and bovid herpesvirus 4 (BHV-4) was investigated in wild ruminants of France and Belgium between 1981 and 1986. There were no animals serologically positive for BHV-4. Antibodies against BHV-2 were demonstrated in roe deer (Cervus capreolus) (less than 1%) and chamois (Rupicapra rupicapra) (1%) in France. Animals seropositive to the four related viruses (BHV-1, BHV-6, HVC-1, reindeer herpesvirus) were detected in red deer (Cervus elaphus) in France and Belgium (1% and 11%, respectively), in roe deer (less than 1%) from France, in chamois (4%) in France and in ibex (Capra ibex) (4%) from France. The presence of antibodies against HVC-1, especially in red deer from Belgium, may suggest that wild ruminants in continental Europe are now infected with this virus, which previously has been isolated only in Scotland.

Upon incubation with human platelets previously labelled with [14C]arachidonic acid, a new immunomodulator, LF 1695, induced the accumulation of [14C]-12-(S)-hydroxy-5,8,10,14-eicosatetraenoic acid (12-HETE). Although the time course of [14C]HETE accumulation was identical with 60 microM LF 1695 and calcium ionophore A23187, the latter compound also promoted the formation of 14C-labelled thromboxane B2 and 12-(S)-hydroxy-5,8,10-heptadecatrienoic acid (HHT), whereas 12-HETE was the only arachidonic acid metabolite generated under the action of LF 1695, suggesting that the drug inhibited cyclo-oxygenase. This was further confirmed by the fact that LF 1695 inhibited the second wave of platelet aggregation induced by ADP as well as arachidonic acid effects. Cell lipid analysis revealed that arachidonic acid was liberated from both triacylglycerol and phosphatidylcholine. The effect was observed in the concentration range 15-90 microM, with a half-maximal effect at 30 microM for HETE production, 15 microM for triacylglycerol hydrolysis and 45 microM for phosphatidylcholine deacylation. Incubation of platelets with [14C]arachidonic acid in the presence of 60 microM LF 1695 resulted in a strong inhibition of arachidonic acid incorporation into the various cell lipids, indicating that arachidonic acid mobilization might be due to inhibition of reacylation processes. It is concluded that LF 1695 displays an original and complex effect on platelet lipid metabolism, resulting in the specific generation of lipoxygenase metabolites.

Cardio-circulatory and neurological complications may appear between the second and seventh day of treatment of severely burnt (greater than 30% of body surface, 3rd degree) patients between the 2nd and 7th day, even if their lesions follow an apparently favorable course. The purpose of the present work was to isolate substances from the sera of such patients which would be responsible for the toxic effects. The sera of several patients were fractionated by Cohn's method n degree 6 and the fractions were tested in vivo in rabbits, rats and mice for their toxic effects. We could demonstrate in some of the fractions (II + III, IV and VI) toxic activity on the central nervous system, on the cardiocirculatory and respiratory systems. An acute toxic activity was also present as well as a substance increasing the permeability of the blood-brain barrier. All these factors together may be involved in the production of the above-mentioned clinical symptoms. Their appearance may depend on the concentration of toxic substances in the blood and on the resistance of the patients.

Blood serum of heavily burned patients contains neurotoxic substances which are not present in normal control sera. In the present paper, we describe the purification by gel filtration and ultracentrifugation of such a neurotoxic factor. The purified factor appeared to be a high molecular weight (2 to 3.10(6) daltons) lipoprotein. This factor was present in all the sera of patients with more than 35 per cent of the body surface burned. When injected into rabbits the lipoprotein caused a flattening of the EEG tracing, then trembling and convulsions with bursts of spikes on the EEG. The activity of this neurotoxic substance was enhanced when the permeability of the blood-brain barrier was increased by previous intraventricular injection of collagenase. The presence of such a neurotoxic factor in the blood serum of burned patients, together with the increased serum collagenase activity they exhibit may explain the neurotoxic symptoms observed in them.