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The effects of BN 52021, a new specific paf-acether receptor antagonist and the total Ginkgo biloba extract (GBE 761) from which this product was isolated, were studied in the rat on paf-acether-induced permeability and cell number changes and on endotoxin-induced lethality. Their activities were compared to those of cycloxygenase, 5-lipoxygenase and phospholipase A inhibitors. BN 52021 given s.c. or orally exerted a dose-related inhibition of paf-acether deleterious effects as well as of endotoxin lethality whereas the other drugs tested were poorly effective. These results strongly suggest paf-acether involvement in endotoxic and septic shock. [ABSTRACT FROM AUTHOR]

Background: Implicit learning of intraoperative auditory stimuli during general anesthesia is very difficult to quantify but may require the presence of noxious stimulation. We hypothesized that an anesthetic regimen with a low dose of opioid would enhance implicit memory, while a regimen with a high dose of opioid would not., Methods: One hundred-twenty patients were randomized into 3 groups. All patients were anesthetized with a target-controlled infusion of propofol and remifentanil, targeting a Bispectral Index (BIS) value of 50. The remifentanil effect-site concentration (in ng/mL) was always double that of propofol (in μg/mL) in the first group and half of that in the second group. Patients in these 2 groups were played a list of 20 words via headphones during surgery. The third group served as control for memory tests and was not played any word during anesthesia. BIS was recorded during word presentation., Results: No statistical difference was found among the 3 groups regarding 3 different memory tests although 67.5% [50.7%; 80.9%] of the patients of the high-opioid group and 72.5% [55.9%; 84.9%] of the low-opioid group had at least 1 episode of BIS >60., Conclusions: We could not demonstrate the presence of implicit or explicit memorization under propofol-remifentanil anesthesia either with a low- or a high-dose opioid anesthetic regimen.

In the immediate postoperative period, some patients present with pain that responds poorly to intravenous opioids. In a double-blind randomized study, we tested the hypothesis that administering small doses of intravenous ketamine (0.125 mg/kg) combined with clonidine (0.5 microg/kg) would enhance the speed of onset and the quality of an opioid analgesic regimen in patients who initially responded poorly to opioids. We enrolled 68 patients in the study, all physical status I to III according to the American Society of Anesthesiologists classification. If the patient's numerical rating scale (NRS) score remained > or = 5 after an initial intravenous injection of 10 mg piritramide (2-mg boluses every 5 minutes) in the post-anesthesia care unit, patients were randomized to either intravenous placebo (sodium chloride 0.9%) or active substances (ketamine 0.125 mg/kg plus clonidine 0.5 microg/kg). Fifteen minutes after administration of either placebo or active agents, patients with severe pain (NRS > 4) again received intravenous opioids until NRS < 4. The primary endpoint of the study was to reduce by 20 minutes the time necessary to achieve an NRS < 4. There was no statistically significant difference between the two groups regarding the time required for patients to achieve an NRS < 4. It was concluded that in the immediate postoperative period, the acute administration of small combined doses of intravenous ketamine (0.125 mg/kg) and clonidine (0.5 mirog/kg) does not reduce the onset of an opioid-based analgesia in patients with an initial poor response to intravenous opioids.

Background: In 1994 we started recombinant human deoxyribonuclease (rhDNase) in every cystic fibrosis (CF) patient whatever his (her) clinical condition, provided they were aged more than 5 years and forced vital capacity (FVC) was > or = 40%., Population and Methods: We reviewed retrospectively the effects of rhDNase in 69 CF children and adolescents during a 2-year follow-up. Patients (35 boys, 34 girls) received 2.5 mg of rhDNase once daily from a mean age of 8.5 years (range 5-16.4). Baseline spirometric values (% predicted) and nutritional status were as followed: FVC = 84.8 +/- 21.7; forced expiratory volume in 1 second (FEV1) = 80.8 +/- 22.2; peak flow = 89.7 +/- 34.2, forced expiratory fraction 25-75% (FEF 25-75) = 71.8 +/- 32.8; Z score weight/height = -0.41 +/- 1.14; Z score weight/age = -0.48 +/- 1.25, body mass index = 15.4 +/- 1.8; caloric intake = 107 +/- 25% of recommended dietary allowances (RDA). Patients had a Shwachman-Kulczycki's score of 87 +/- 9. Spirometric and nutritional data were analysed after 1, 3, 6, 12, 18 and 24 months of treatment and compared to baseline values (changes evaluated as percent change from mean baseline for spirometric data). Shwachman-Kulczycki's score was calculated after 24 months of rhDNase., Results: An improvement of FVC (+10.7%, P < 0.001) and FEV1 (+12%, P < 0.01) was noted after one month of treatment and was maintained throughout the following 2 years around 8.7% (6.4-11.4) for FVC and 8.2% (7.3-9.1) for FEV1, P < or = 0.01. This was particularly observed in children aged 5 to 10 years, in boys and in patients with a baseline FVC under 70% predicted. There was no significant change in FEF 25-75. We observed an improvement of daily caloric intake from the third month (P < 0.05) and of body mass index from the sixth month (P = 0.02). This was particularly noted in girls. Z score weight/age was improved only during the first 3 months of treatment while Z score weight/height increased only after a 2 year follow-up. There was no significant change in Shwachman-Kulczycki's score after 24 months of rhDNase., Conclusion: rhDNase in CF children in effective on lung function as well as on nutritional status and the response to this treatment can be evaluated after the first 3 months.

Since proteolytic enzymes play a key role in endotoxaemia and anaphylaxis, diseases in which PAF-acether may be involved, we have investigated the activity of BN 52021 and BN 52063, two potent and specific PAF-acether antagonists, on plasma protease activity in the rat. After oral administration, both drugs dose-dependently decreased plasma trypsin-like activity (PTLA) although they did not show any inhibitory effect in vitro. PAF-acether and endotoxin injected into rats increased PTLA, the increase with endotoxin appearing more slowly but to a higher extent than with PAF-acether. Inhibition of the endotoxin-induced increase in PTLA was obtained with BN 52021, BN 52063 and dexamethasone, whereas aprotinin was ineffective. Since BN 52021 and BN 52063 reduced also the endotoxin-induced lethality in the rat, their antiprotease activity may be a consequence of their PAF-antagonistic effect. Further studies will be required with other PAF antagonists to assess fully this assumption.

The effects of different concentrations of an extract of Ginkgo biloba (Gb) and of chlorpromazine (CPZ) on the osmotic lysis of rat erythrocytes (produced by dilution of the incubation medium by 30%-70%) were compared in vitro. The erythrocytes were incubated together with Gb or Cpz at the time of the hemolytic reaction at 25 degrees or 37 degrees C in either a simple phosphate buffer or in a more complete buffer containing inorganic salts at physiological concentrations. CPZ produced a dose-dependent increase in the membrane resistance, the maximum effect occurring at 10(-4) M regardless of the experimental conditions used. Gb also increased membrane resistance, but to a lesser extent than CPZ. In addition, Gb was more effective under conditions which increased erythrocyte membrane fragility; i.e., 37 degrees C, simple phosphate buffer. The mechanism of action of Gb seems to differ from that of CPZ. The activity of CPZ (as a membrane stabilizer) is, in part, due to its penetration into the membrane phospholipid layer. Gb might act in a similar manner, but could also modify Na+ transport across the cell membrane by an action on adrenergic receptors, or could stimulate Na+, K+-ATP-ase activity, as has been described for norepinephrine. As Gb contains many molecular constituents: its action on the membrane is likely to be quite complex; but this effect could be associate with its vascular therapeutic action.

Oedema is one of the major complication of cerebral ischaemia being at the same time a consequence and an aggravating factor. Its first phase is intracellular and cytotoxic, with breakdown of ionic pumps through loss of energy, resulting in a whole sequence of ionic perturbations characterized by loss of intracellular K+ and accumulation of water and Na+, Cl-, and Ca2+ ions in the cells of the ischaemic zone. The second phase, termed vasogenic, applies to the accumulation of lactates, inorganic phosphates and free polyunsaturated fatty acids and in particular, arachidonic acid. This last compound is responsible for the production of membrane "aggressors", amongst which free radicals play an important rôle. Ginkgo biloba extract limits the formation of cerebral oedema and suppresses its neurological consequences, whether the oedema is of cytotoxic (triethyltin) or vasogenic (unilateral traumatic oedema) origin. Several membrane mechanisms could be implicated in the protective action manifested by Ginkgo biloba extract against cerebral oedema.