Double lethal coconut crab (Birgus latro L.) poisoning.

We report a double lethal coconut crab Birgus latro L. poisoning in New Caledonia. Both patients died after showing gastro-intestinal symptoms, major bradycardia with marked low blood pressure, and finally asystolia. Both had significative hyperkaliemia, suggesting a digitaline-like substance intoxication. Traditional knowledge in the Loyalty Islands relates coconut crab toxicity to the consumption of the Cerbera manghas fruit by the crustacean. Elsewhere previous descriptions of human poisoning with the kernel of fruits of trees belonging to the genus Cerbera, known to contain cardiotoxic cardenolides, appear to be very similar to our cases. Cardenolides assays were performed on patient's serum samples, fruit kernel and on the crustacean guts, which lead us to suppose these two fatal cases were the result of a neriifolin intoxication, this toxin having been transmitted through the coconut crab.

Screening of New Caledonian and Vanuatu medicinal plants for antiprotozoal activity.

Sixty-seven extracts of 30 medicinal plants traditionally used in New Caledonia or Vanuatu by healers to treat inflammation, fever and in cicatrizing remedies were evaluated in vitro for their antiprotozoal activity against Leishmania donovani, Leishmania amazonensis and Trypanosoma cruzi. Among the selected plants, Pagiantha cerifera was the most active against both Leishmania species; four extracts were active against promastigotes of Leishmania donovani at EC(50) values inferior to 5 microg/ml. Garcinia pedicillata extract had an EC(50) value of 12.5 microg/ml against intracellular amastigotes of Leishmania amazonensis. Alone Amborella trichopoda reduced by more of 80% the trypomastigotes of Trypanosoma cruzi in the blood.

Screening of some New Caledonian and Vanuatu medicinal plants for antimycobacterial activity.

Twenty plants, belonging to sixteen families, used in traditional New Caledonian and Vanuatu medicine for treatment of symptoms potentially related to tuberculosis (cough, fever or inflammation) were screened for antimycobacterial activity. We also screened an original endemic plant, Amborella trichopoda, only member of the monogeneric family Amborellaceae and considered the most primitive living angiosperm. In total, 55 extracts were evaluated for inhibitory activity against Mycobacterium bovis BCG strain at a concentration of 100 microg/ml. Methanolic and dichloromethane extracts of Amborella trichopoda, Codiaeum peltatum, Myristica fatua, and essential oils Myoporum crassifolium showed an activity at this concentration. Methanolic extract of Amborella trichopoda fruits presented a significant activity with a minimal inhibitory concentration included between 1 and 2.5 microg/ml. In the same conditions, this activity was comparable with those of the reference drugs pyrazynamide and ethambutol, at 20 and 2.5 microg/ml, respectively.

Natural and synthetic benzophenones: interaction with the cytosolic binding domain of P-glycoprotein.

A benzophenone glycoside has been isolated from Davallia solida. Its structure was elucidated by chemical and spectral means as 4-O-beta-D-glucopyranosyl-2,6,4'-trihydroxybenzophenone. It bound with moderate affinity to the purified C-terminal cytosolic domain of P-glycoprotein, but the binding affinity was 6- to 10-fold increased for its aglycone derivative and other related benzophenones.

In vitro antiplasmodial activity of extracts of Tristaniopsis species and identification of the active constituents: ellagic acid and 3,4,5-trimethoxyphenyl-(6'-O-galloyl)-O-beta-D-glucopyranoside.

Screening of plants from New Caledonia for antiplasmodial activity against Plasmodium falciparum revealed that methanolic extracts of the leaves and bark of Tristaniopsis calobuxus, T. yateensis, and T.glauca inhibited the growth of chloroquine-sensitive and -resistant clones. Ellagic acid and the new compound 3,4,5-trimethoxyphenyl-(6'-O-galloyl)-O-beta-D-glucopyranoside were identified as the active constituents (IC50 0.5 and 3.2 microM, respectively). The growth inhibition of both clones was comparable. The compounds showed negligible or very low cytotoxicity to human skin fibroblasts and Hep G2 cells when tested at concentrations ranging from 0.5 to 100 microM.

Traditional remedies used in the western Pacific for the treatment of ciguatera poisoning.

Ciguatera is a specific type of food poisoning associated with the ingestion of tropical fish, which, although normally safe for consumption, may at times contain high amounts of ciguatoxin, as well as other chemically related toxins. Widespread in tropical regions where coral reefs are present, ciguatera fish poisoning constitutes a major hindrance for local fishing industries, local economies and foreign trade. Because no symptomatic treatment has been totally satisfactory, folk remedies remain of great interest. In this paper, a list of plants used in treating ciguatera poisoning in the Western Pacific region is presented, with emphasis on species whose exact utilization (part of plant used, preparation, dosage) has been determined.

In vitro cytotoxicity of polyindolenine alkaloids on rat hepatoma cell lines. Structure activity relationships.

New groups of polyindolenine alkaloids have been isolated from new species of the tribe Psychotriae (Rubiaceae). The cyto-inhibitory effects of these compounds on tumoral cell lines have been thoroughly investigated and thus allow the statement of relationships between some original structural patterns and the observed biological effects.

Behavioral effects of Euphorbia hirta L.: sedative and anxiolytic properties.

Lyophilised aqueous extract of Euphorbia hirta L. (Euphorbiaceae) has been evaluated for behavioral effects in mice. The extract did not induce any toxic effect when it was administered i.p. and orally. Sedative properties could be confirmed with high doses (100 mg of dried plant/kg, and more), by a decrease of behavioral parameters measured in non-familiar environment tests (activitest and staircase test), whereas anticonflict effects appeared at lower doses (12.5 and 25 mg of dried plant/kg), by an enhancement of behavioral parameters measured in the staircase test and in the light/dark choice situation test. These findings validate the traditional use of E. hirta as a sedative and reveal original anxiolytic properties.

Alcaloïdes des Annonacées XLIX1: alcaloïdes d'Isolona hexaloba, I zenkeri et I. pilosa.

From ISOLONA HEXALOBA, I. ZENKERI and I. PILOSA, thirteen alkaloids have been isolated. Four of them are bisbenzylisoquinolines, the other ones are proaporphines or aporphines. Two aporphines, zenkerine, 9, and isopiline, 13, are new. Their structures have been established by examination of their spectral data and preparation of derivatives.

[Alkaloids from annonaceae.]. / Alcaloïdes des Annonacées.

From diverse parts of POLYALTHIA NITIDISSIMA, thirteen isoquinoline alkaloids have been isolated and identified. They belong to the structural types of benzylisoquinolines, aporphinoids, protoberberines and mainly bisbenzylisoquinolines. Four of these dimers, namely N,N'-dimethyllindoldhamine, isodaurisoline, 7-O-methyllindoldhamine and 7'-O-methyllindoldhamine, are new natural products.

Etude des hernandiacées.

The alkaloidal content of the leaves and stem barks of H. peltata has been studied; eleven alkaloids and three lignans are isolated from the leaves, eleven alkaloids from the stem barks. Thirteen different alkaloids are identified by means of the spectral analysis; twelve are aporphines and nor-aporphines.