J Ethnopharmacol
January 2005
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.
View Article and Find Full Text PDFThree Annonaceous acetogenins exhibited in vitro antimalarial activities on a chloroquine-resistant Plasmodium falciparum strain, with IC50s ranging from 5 to 10 microM. Structure-activity relationships showed that maximal antimalarial activity occurred in the presence of at least one tetrahydrofuran moiety and a synergistic action with chloroquine was observed. These acetogenins partially inhibited the P.
View Article and Find Full Text PDFTwelve acetogenins from Annonaceae were evaluated in vitro for their antileishmanial activities in order to search for new lead-compounds having antileishmanial properties. The compounds were comparatively evaluated by the 50% inhibitory concentrations (IC50) determination on promastigote forms of wild-type and four drug-resistant lines of Leishmania donovani. In addition, after testing the toxicity on mouse peritoneal macrophages, the compounds were evaluated on amastigote infected macrophages and a therapeutic index was calculated.
View Article and Find Full Text PDFThe 24-alkylated sterols have been shown previously to be absent in membranes of amphotericin B (AmB)-resistant Leishmania donovani promastigotes, suggesting that the S- adenosyl-l-methionine:C-24-Delta-sterol-methyltransferase (SCMT or ERG6) was not functional or not expressed in AmB-resistant (AmB-R) parasites. From an L. donovani wild-type clone, we cloned two cDNAs with an identical open reading frame encoding a putative SCMT, the enzyme responsible for a first sterol methylation at the C-24 position.
View Article and Find Full Text PDFUnlabelled: 99mTc-Annexin-V (ANX), which allows in vivo detection of apoptotic cells, is potentially a promising noninvasive tool to diagnose myocarditis. To test this assumption, we compared the myocardial uptake of ANX (imaging and quantitative autoradiography) in experimental subacute myocarditis (Wistar Bonn/Kobori rats [WBN/Kob]) and in normal Wistar rats. WBN/Kob is an inbred strain of Wistar rat in which myocardial injury mimicking subacute catecholamine-induced myocarditis spontaneously develops (course duration, 18 mo).
View Article and Find Full Text PDFThe efficacy and pharmacokinetics of a new parenteral formulation of halofantrine were studied in mice infected with Plasmodium berghei. The formulation consisted of nanocapsules with an oily core, prepared from either poly(D,L-lactide) (PLA) homopolymer or PLA that was surface modified with grafted polyethylene glycol chains. They were compared with a previously described intravenous halofantrine preparation.
View Article and Find Full Text PDFWe carried out a multicenter performance evaluation of three new DNA-based human leukocyte antigen (HLA) typing assays: INNO-LiPA HLA-A Update, INNO-LiPA HLA-B Update, and INNO-LiPA HLA-DQB1 Update. After optimization, the accuracy rates were all 100%, and the final observed resolutions were 99.4, 92.
View Article and Find Full Text PDFThe phospholipid analogue miltefosine or hexadecylphosphocholine (HePC) is a drug of high interest in the treatment for fatal visceral leishmaniasis (VL) due to Leishmania donovani particularly because of its activity by oral route. In this study, the interaction of HePC with a monolayer of beta-palmitoyl-gamma-oleyl-phosphatidylcholine (POPC) as membrane model or sterol (ergosterol or cholesterol) was investigated. At a constant pressure of 25 mN/m, the adsorption kinetics of HePC into the monolayers showed that HePC molecules are inserted into the monolayer of lipids as monomers until the critical micellar concentration (CMC).
View Article and Find Full Text PDFAntimicrob Agents Chemother
March 2004
Miltefosine (hexadecylphosphocholine [HePC]) has proved to be a potent oral treatment for human visceral leishmaniasis due to Leishmania donovani. The molecular mechanisms that contribute to the antileishmanial activity of HePC are still unknown. We report that in wild-type promastigotes of Leishmania donovani HePC is able to induce a cell death process with numerous cytoplasmic, nuclear, and membrane features of metazoan apoptosis, including cell shrinkage, DNA fragmentation into oligonucleosome-sized fragments, and phosphatidylserine exposure.
View Article and Find Full Text PDFObjective: To determine whether cytokine gene polymorphisms of interferon-gamma (IFNgamma), interleukin-6 (IL-6), IL-10, tumor necrosis factor alpha (TNFalpha), and transforming growth factor beta1 (TGFbeta1) predispose subjects to the development of primary Sjögren's syndrome (SS).
Methods: Single-base-exchange cytokine gene polymorphisms were analyzed in 129 French patients with primary SS who fulfilled the American-European Consensus Group criteria, as well as in 96 unrelated healthy subjects.
Results: The frequency of the TNF-308A (TNF2) allele was significantly higher in the SS patients (26% versus 11%).
During an ethnopharmacological survey of antiparasitic medicinal plants used in Ivory Coast, 17 plants were identified and collected. Polar, non-polar and alkaloidic extracts of various parts of these species were evaluated in vitro in an antiparasitic drug screening. Antimalarial, leishmanicidal, trypanocidal, antihelminthiasis and antiscabies activities were determined.
View Article and Find Full Text PDFAntimicrob Agents Chemother
December 2003
The aim of the present study was to evaluate the toxicity and the activity of a new lipid complex formulation of amphotericin B (AMB) (LC-AMB; dimyristoyl phosphatidylcholine, dimyristoyl phosphatidylglycerol, and AMB) that can be produced by a simple process. Like other lipid formulations, this new complex reduced both the hemolytic activity of AMB (the concentration causing 50% hemolysis of human erythrocytes, >100 microg/ml) and its toxicity toward murine peritoneal macrophages (50% inhibitory concentration, >100 microg/ml at 24 h). The in vivo toxicity of the new formulation (50% lethal dose, >200 mg/kg of body weight for CD1 mice) was similar to those of other commercial lipid formulations of AMB.
View Article and Find Full Text PDFStimulation of nitrification and denitrification by long term (from years to decades) grazing has commonly been reported in different grassland ecosystems. However, grazing generally induces important changes in plant species composition, and whether changes in nitrification and denitrification are primarily due to changes in vegetation composition has never been tested. We compared soil nitrification- and denitrification-enzyme activities (NEA and DEA, respectively) between semi-natural grassland sites experiencing intensive (IG) and light (LG) grazing/mowing regimes for 13 years.
View Article and Find Full Text PDFObjective: To reevaluate, in a large series of patients with Sjögren's syndrome (SS) recruited from 2 French centers, the question of whether HLA is associated with SS itself or with a pattern of secretion of autoantibodies.
Methods: One hundred forty-nine white patients fulfilling the American-European Consensus Group criteria for SS were divided into 3 subgroups, according to their anti-Ro/SSA and anti-La/SSB status, as follows: group 1 (n = 53), no antibody; group 2 (n = 46), anti-SSA only; group 3 (n = 50), both anti-SSA and anti-SSB. Patients were compared with 222 unrelated healthy subjects representative of the white population in France.
Modulation of cytokine expression represents a potentially useful approach for the treatment of idiopathic pulmonary fibrosis (IPF). To identify potential targets for such intervention, semi-quantitative reverse transcriptase-polymerase chain reaction was used to compare the expression of messenger ribonucleic acids (mRNAs) coding for 17 cytokines in lung tissue obtained from patients with IPF at the time of diagnosis and control subjects. Some cytokines were also studied at the protein level by immunohistochemical techniques.
View Article and Find Full Text PDFWe have studied the antiprotozoal activity of some recently prepared and characterized arsonoliposome formulations. Plain arsonoliposomes and phosphatidylcholine arsonoliposomes prepared with palmitoyl- (C16) or lauroyl-(C12) acyl side chain arsonolipids showed in-vitro antileishmanial activity after a 72-h incubation period against wild-type promastigote forms of Leishmania donovani. The IC50 values ranged from 0.
View Article and Find Full Text PDFThe acaricidal effects of tonka bean, Dipterix odorata, extracts were investigated on Dermatophagoides pteronyssinus, the European house dust mite, and compared with benzyl benzoate as a standard acaricidal compound. A cyclohexane extract was the most effective, with an EC(50) = 0.075 g/m(2) after a 24 h period, as compared with benzyl benzoate (0.
View Article and Find Full Text PDFThe aim of the work was to develop a new submicronic delivery system that can be used with poorly water soluble drugs for which sustained circulating concentrations are necessary. This system consists of oily core surrounded by a shell made of a copolymer of poly (D,L-lactid) and poly (ethylene glycol). Covalent coupling between the hydrophylic poly (ethylene glycol) and poly (D,L lactid) and high molecular weight of the poly (ethylene glycol) chains yield long circulating particles after intra-venous administration in mice.
View Article and Find Full Text PDFThe activity of formulations for amphotericin B (AmB) associated with poly(epsilon-caprolactone) nanospheres and coated with variable amounts of a non ionic surfactant poloxamer 188, was evaluated against AmB-susceptible (WT) and AmB-resistant (AmB(r)) strains of Leishmania donovani amastigotes in thioglycolate-elicited peritoneal macrophages. AmB-nanospheres were more actives than free AmB only against amastigotes of wild strain. The activity was not influenced by the concentration of poloxamer 188 used to stabilize the nanospheres in spite of this surfactant was previously reported to synergy with AmB on the membrane of the resistant parasite.
View Article and Find Full Text PDFPemphigus is a group of autoimmune blistering diseases caused by autoantibodies directed against keratinocyte adhesion molecules. Pemphigus vulgaris (PV) and pemphigus foliaceus (PF), in which autoantibodies bind, respectively, to desmoglein 3 and desmoglein 1, are strongly associated with HLA-class II DR4 and DR14 alleles. In paraneoplastic pemphigus (PNP), a rare variant associated with neoplasia, autoantibodies target proteins of the plakin family in addition to desmogleins 1 and 3.
View Article and Find Full Text PDFChitinolytic activities in Trichomonas vaginalis membrane extracts were assessed by assays of three enzyme systems: N-acetyl-beta-D-hexosaminidase (NAHase), chitobiosidase and chitotriosidase. N-acetyl-beta-D-hexosaminidase was the enzyme that showed the highest specific activity. After successive subcutaneous inoculations into mice and parasite recovery in culture, the enzyme activities increased significantly with the number of inoculations for up to eight passages.
View Article and Find Full Text PDFIn order to evaluate the impact of HLA-DBP1 incompatibilities on the occurrence of acute graft-versus-host disease (GVHD) in unrelated hematopoietic cell transplantation, we studied 57 donor/recipient pairs characterized by their allelic identity for HLA-A, B, C, DRB1 and DQB1 and also for DRB3, 4, 5 loci and aimed to correlate DPB1 mismatches to already described risk factors for GVHD using multivariate Cox regression analysis. DPB1 identity between donor and recipient was observed in 24% and DPB1 compatibility (GVHD vector) in 42%. Two factors were independently associated with severe acute GVHD: two DP incompatibilities (RR = 8.
View Article and Find Full Text PDFThe Sixth Eilat Conference on New Antiepileptic Drugs (AEDs) took place in Taormina, Sicily, Italy from 7th to 11th April, 2002. Basic scientists, clinical pharmacologists and neurologists from 27 countries attended the conference, whose main themes included dose-response relationships with conventional and recent AEDs, teratogenic effects of conventional and recent AEDs, update on clinical implications of AED metabolism, prevention of epileptogesis, and seizure aggravation by AEDs. According to tradition, the central part of the conference was devoted to a review of AEDs in development, as well to updates on AEDs, which have been marketed in recent years.
View Article and Find Full Text PDFSome perketals were synthesized by the Dussault procedure using simple bromides and 2-methoxyprop-2-yl hydroperoxide. Treatment with acetic acid gave the corresponding hydroperoxides. Both perketals and hydroperoxides were tested in vitro as trichomonacidal agents.
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