Evaluation of epoxiconazole bioavailability in soil to the earthworm Aporrectodea icterica.

In soil, the determination of total concentration using an exhaustive extraction method has little relevance to evaluate the exposure of an organism to a chemical, because of sorption processes. This study aims to propose a mild extraction method to evaluate the bioavailability of the fungicide epoxiconazole to the earthworm Aporrectodea icterica. Experiments were conducted in soils presenting various textures and organic carbon contents, spiked with formulated epoxiconazole 7 to 56 days prior to their extraction. In parallel, the epoxiconazole concentration was determined in exposed earthworms and the fungicide's effects were evaluated by measuring weight gain, enzymatic activities and total protein contents. Among the various mild chemical solvents tested to evaluate the environmental availability of the fungicide, the 50 mM hydroxypropyl-ß-cyclodextrin solution allowed to extract around 30% of epoxiconazole. This percentage corresponded to the ratio determined in exposed A. icterica under similar soil conditions. Furthermore, this mild method was demonstrated to be sensitive to soil sorption capacities and to ageing. The mild extraction method was then applied to explore the relationship between total and (bio)available concentrations in soil and in A. icterica, over 7- or 28-day exposure time. This demonstrated the proportionality between epoxiconazole concentration in earthworm and available in soil (up to 96%, with regression coefficient R(2) = 0.98). Sublethal effects on earthworm remained not significant.

In vitro and in vivo antimutagenic effects of DIG, a herbal preparation of Berberis vulgaris, Taraxacum officinale and Arctium lappa, against mitomycin C.

DIG, a liquid herbal preparation made from a mixture of diluted mother tinctures of Berberis vulgaris, Taraxacum officinale and Arctium lappa, was assessed for its antimutagenic properties against mitomycin C. The micronucleus assay on Chinese hamster ovary (CHO)-K1 cells was used to evaluate the in vitro anticlastogenic activity of DIG compared to those of separately diluted mother tinctures. The micronucleus assay was performed on mouse erythrocytes and the comet assay was performed on mouse liver, kidney, lung, brain and testicles to assess the protective effects of DIG (0.2 and 2 % at libitum) against an intraperitoneal injection of mitomycin C (1 mg Kg(-1)) in mice. DIG exerted a powerful anticlastogenic activity, under both pretreatment and simultaneous treatment conditions as assessed by the micronucleus assay in CHO-K1 cells. Its protective activity was greater than that observed for each mother tincture. DIG reduced micronuclei levels in mouse erythrocytes and suppressed >80 % of DNA strand breaks in the liver, kidney, lung, brain and testicles of mice exposed to mitomycin C.

Safety of spironolactone in dogs with chronic heart failure because of degenerative valvular disease: a population-based, longitudinal study.

BACKGROUND: Spironolactone treatment in humans is associated with an increased risk of hyperkalemia and renal dysfunction. HYPOTHESIS: Dogs with cardiac disease treated with spironolactone, in addition to conventional therapy, are not at higher risk for adverse events (AEs) than those receiving solely conventional therapy. ANIMALS: One hundred and ninety-six client-owned dogs with naturally occurring myxomatous mitral valve disease. METHODS: Prospective, double-blinded field study with dogs randomized to receive either spironolactone (2 mg/kg once a day) or placebo in addition to conventional therapy (angiotensin-converting enzyme inhibitor, plus furosemide and digoxin if needed). Safety was compared between treatment groups, using the frequency of AEs, death caused by cardiac disease, renal disease, or both, and variations in serum sodium, potassium, urea, and creatinine concentrations. For the latter, population-specific reference intervals were established and out of range values (ORV) analyzed. RESULTS: The number of AEs was similar in the spironolactone and reference groups (188 and 208, respectively), when followed for median duration of 217 days (range [2-1,333]). At each study time point, the percentage of dogs showing ORV was similar between groups. There were a higher number of deaths because of cardiac disease, renal disease or both in the reference group (30.7% versus 13.7%) (P = .0043). CONCLUSIONS AND CLINICAL IMPORTANCE: Dogs with heart failure receiving spironolactone in addition to conventional treatment are not at a higher risk for AEs, death caused by cardiac disease, renal disease, or both, hyperkalemia, or azotemia.

Genotoxic and clastogenic activity of saponins extracted from Nauclea bark as assessed by the micronucleus and the comet assays in Chinese Hamster Ovary cells.

ETHNOPHARMACOLOGICAL RELEVANCE: Bark extracts of Nauclea latifolia, Nauclea diderrichii, Nauclea pobeguinii and Nauclea vandergutchii are used in traditional medicine in West and South Africa for the treatment of fevers, diarrhea and malaria. AIM OF THE STUDY: To estimate the possible long-term toxicity and genotoxicity of plant extracts (dichloromethane, methanol, water/methanol, water) and saponins. MATERIALS AND METHODS: The clastogenicity of plant extracts and saponins was assessed by the micronucleus assay performed on Chinese Hamster Ovary cells. The DNA-damaging activity of saponin mixture was assessed by the comet assay on Chinese Hamster ovary cells. RESULTS: Hydromethanolic extracts from Nauclea latifolia, Nauclea diderrichii and Nauclea pobeguinii exhibited a significant clastogenic/aneugenic activity without S9 mix. The hydromethanolic extract from Nauclea diderrichii was the most clastogenic/aneugenic fraction with a Minimal Active Concentration (MAC) of 23.1 µgm L(-1). It was submitted to a separation step leading to six main saponins identified as quinovic acid glycosides (saponins A, D, E, G, J, K). None of the isolated saponins exerted a significant clastogenic/aneugenic activity by the micronucleus assay, however a mixture made with equal quantities of each of the six saponins exhibited a direct genotoxic/clastogenic activity as assessed by both the micronucleus assay and the comet assay on Chinese Hamster Ovary cells. CONCLUSION: Saponins present in the hydromethanolic extracts of Nauclea induced synergistic in vitro DNA-damage and chromosome mutations in mammalian cells. This genotoxic activity was probably due to the capacity of Nauclea saponins to reduce cell defense against oxidative stress through the inhibition of glutathione-S-transferase activity.

Antiplasmodial, anti-inflammatory and cytotoxic activities of various plant extracts from the Mascarene Archipelago.

AIM OF THE STUDY: Antiplasmodial activity, inhibition of nitric oxide (NO) overproduction, and anti-proliferative activity were investigated in vitro to evaluate the bioactive potential of the traditional pharmacopoeia of the Mascarene Archipelago, which is known for its biodiversity and for the richness of its endemic flora. MATERIALS AND METHODS: A total of 45 methanol (MeOH) and dichloromethane (DCM) extracts were prepared from 19 plant species collected on Réunion and Mauritius Islands. Ninety-six-well microplate assays were performed on chloroquine sensitive Plasmodium falciparum 3D7 strain, on LPS-stimulated Raw 264.7 murine macrophages and on A-549, DLD-1 and WS1 human cells. Activity was evaluated through spectrophotometric methods. RESULTS: Activity was attributed to plant extracts expressing IC(50)<50µg/ml for antiplasmodial response, IC(50)<100µg/ml for cytotoxicity, and IC(50)<130µg/ml for anti-inflammatory reaction. The majority of the extracts tested (69%) exhibited potency in at least one of these three types of activity. This is the first report describing promising antiplasmodial activity (IC(50)<15µg/ml) for Psiadia dentata DCM extract and Terminalia bentzoe MeOH bark extract. NO inhibition assay revealed seven interesting plants, described for the first time as anti-inflammatory: Aphloia theiformis, Buddleja salviifolia, Eupatorium riparium, Hiptage benghalensis, Psiadia arguta, Psiadia dentata, and Scutia commersonii. Finally, anti-proliferative activity was observed for two endemic species, Geniostoma borbonicum and Nuxia verticillata. CONCLUSION: Using the criterion of endemism as part of the criteria for traditional medicinal use raises the chances of finding original active principles. In our case, 86% of the endemic plants tested displayed pharmacological interest.

Effect of green tea extracts on liver functions in Wistar rats.

An herbal medicinal product (Exolise) containing as active ingredient an hydro-alcoholic extract of green tea named AR25 (standardized to 25% catechins) has been implicated in hepatic failures, leading to the withdrawal of the marketing authorization. The active ingredient of Exolise being manufactured with 80% ethanol, the question to know whether the extraction solvent could introduce some toxic components was hypothesized. Two investigations were conducted in Wistar rats to determine if repeated oral administration of different green tea extracts could corroborate the reported hepatotoxicity in humans. In a preliminary 6 week-study, experimental groups (n=9/group) received either the vehicle or a methylene chloride extract (2500 mg/kg body weight) where potential non-polar hepatotoxin(s) could be concentrated. In a second experiment (12 week-study), rats were divided in three groups (n=10/group) and treated with either the vehicle, or an aqueous extract (1400 mg/kg) or AR25 green tea extract (2000 mg/kg). Rat liver functions were assessed by serum biochemistry of hepatotoxicity markers. No sign of evidence of characteristic hepatotoxicity was found in rats treated with very high amount of different green tea extracts in these two experiments (respectively a daily dosage, which was about 900 and 80 times higher to the therapeutic daily dosage of Exolise.

Screening of 14 alkaloids isolated from Haplophyllum A. Juss. for their cytotoxic properties.

Further to a systematic chemotaxonomic study of Uzbek Haplophyllum A. Juss. plants selected on ethnopharmacological data, 14 alkaloids were screened for their cytotoxic properties. As a first selection for interesting compounds, each alkaloid was tested against two human cancer cell lines (HeLa and HCT-116), using WST-1 reagent. Of the 14 alkaloids, 5 were cytotoxic when tested against the HeLa line with an IC50 < 100 microM. These five compounds consisted of three furoquinolines: skimmianine; haplopine and gamma-fagarine and two pyranoquinolones: flindersine and haplamine. Only haplamine was active against the HCT-116 line. The cytotoxic properties of these five alkaloids were further investigated against five additional human cancer cell lines. Their structure-activity relationships will be discussed. Of these five pre-selected alkaloids, only haplamine showed significant cytotoxic activity against all the tested cell lines. This is the first report of the cytotoxic activity of haplamine. Finally, this pyranoquinolone alkaloid was tested here against 14 different cancer cell lines and against normal skin fibroblasts.

In vitro cytotoxic, antileishmanial and antifungal activities of ethnopharmacologically selected Gabonese plants.

Seventy-seven crude extracts from leaves and stem barks of 15 Gabonese plants used in traditional medicine were evaluated for their cytotoxic, antileishmanial and antifungal activities. Most of the extracts exhibited cytotoxic activities toward human monocytes, and most particularly the hydromethanolic 50% (v/v) fraction of Ganophyllum giganteum leaves (IC(50)=1.3 microg/ml) as well as the methanolic extracts of Polyalthia suaveolens, Dioscorea preussii, Augouardia letestui leaves and Cola lizae stem barks (IC(50)<5 microg/ml). The methanolic extract of Polyalthia suaveolens displayed a strong antiproliferative activity against the promastigote form of Leishmania infantum parasites and presented a good antifungal activity on all the tested strains (IC(50)<1mg/ml). This extract was divided into six fractions: fraction F6 demonstrated a cytotoxic activity stronger than those of the crude extract (IC(50)=0.6 microg/ml), fractions F4 and F5 were devoid of cytotoxicity (IC(50)>100 microg/ml) and displayed interesting antileishmanial activity against the intracellular amastigote form of the parasite (IC(50)=5.6 and 12.4 microg/ml), respectively. However, the antifungal activity observed for the crude extract could not be recovered in the corresponding fractions.

Gluco-indole alkaloids from the bark of Nauclea diderrichii. 1H and 13C NMR assignments of 3alpha-5alpha-tetrahydrodeoxycordifoline lactam and cadambine acid.

Detailed (1)H and (13)C NMR assignments of 3alpha-5alpha-tetrahydrodeoxycordifoline lactam and cadambine acid, isolated from the bark of the Nauclea diderrichii (de Wild.) Merr. (Rubiaceae) were achieved by 1D and 2D techniques such as DEPT, HMBC, HMQC, COSY and NOESY.

In vitro activity of the beta-carboline alkaloids harmane, harmine, and harmaline toward parasites of the species Leishmania infantum.

Harmane, harmine, and harmaline were investigated for their in vitro antileishmanial activity toward parasites of the species Leishmania infantum. Harmane and Harmine displayed a moderate antiproliferative activity toward human monocytes and exerted a weak antileishmanial activity toward both the promastigote and the amastigote forms of the parasite. Their mechanism of action on the promastigote form of the parasite involved interactions with DNA metabolism leading to an accumulation of parasites in the S-G(2)M phases of the cell-cycle. Harmaline, at the contrary, was deprived from toxicity toward human cells and Leishmania promastigotes, however it exerted a strong antileishmanial activity toward the intracellular amastigote form of the parasite. This property was shown to partly result from the capacity of the molecule to prevent parasite internalization within macrophages by inhibiting Leishmania PKC activity.

Ethnobotanical survey and in vitro antiplasmodial activity of plants used in traditional medicine in Burkina Faso.

In Burkina Faso, most people in particular, in rural areas, use traditional medicine and medicinal plants to treat usual diseases. In the course of new antimalarial compounds, an ethnobotanical survey has been conducted in different regions. Seven plants, often cited by traditional practitioners and not chemically investigated, have been selected for an antiplasmodial screening: Pavetta crassipes (K. Schum), Acanthospermum hispidum (DC), Terminalia macroptera (Guill. et Perr), Cassia siamea (Lam), Ficus sycomorus (L), Fadogia agrestis (Schweinf. Ex Hiern) and Crossopteryx febrifuga (AFZ. Ex G. Don) Benth. Basic, chloroform, methanol, water-methanol and aqueous crude extracts have been prepared and tested on Plasmodium falciparum chloroquine-resistant W2 strain. A significant activity has been observed with alkaloid extract of P. crassipes (IC(50)<4 microg/ml), of A. hispidum, C. febrifuga, and F. agrestis (4

Antiplasmodial activity of alkaloid extracts from Pavetta crassipes (K. Schum) and Acanthospermum hispidum (DC), two plants used in traditional medicine in Burkina Faso.

In the course of the search for new antimalarial compounds, a study of plants traditionally used against malaria in Burkina Faso was made. An ethnobotanical study permitted the identification of plants currently used by the traditional healers and herbalists. Two plants among them were selected for further study: Pavetta crassipes (K. Schum) and Acanthospermum hispidum (DC). Alkaloid extracts of these plants were tested in vitro against two reference clones of Plasmodium falciparum: the W2 chloroquine-resistant and the D6 chloroquine-sensitive strains. Significant inhibitory activity was observed with Pavetta crassipes (IC(50)=1.23 microg/ml) and A. hispidum (IC(50)=5.02 microg/ml). Antiplasmodial activity was also evaluated against six Plasmodium falciparum isolates from children between 4 and 10 years old. The IC(50) values for the alkaloid extracts were in the range 25-670 ng/ml. These results indicated that P. falciparum wild strains were more sensitive to the alkaloid extracts than strains maintained in continuous culture. Moreover, the alkaloid extracts exhibit good in vitro antimalarial activity and weak cytotoxicity against three human cell lines (THP1, normal melanocytes, HTB-66). Isolation and structural determination are now necessary in order to precisely determine the active compounds.

Antimalarial activity of extracts and alkaloids isolated from six plants used in traditional medicine in Mali and Sao Tome.

Methanol and chloroform extracts were prepared from various parts of four plants collected in Mali: Guiera senegalensis (Gmel.) Combretaceae, Feretia apodanthera (Del.) Rubiaceae, Combretum micranthum (Don.) Combretaceae, Securidaca longepedunculata (Fres.) Polygalaceae and two plants -collected in Sao Tome: Pycnanthus angolensis (Welw.) Myristicaceae and Morinda citrifolia (Benth.) Rubiaceae were assessed for their in vitro antimalarial activity and their cytotoxic effects on human monocytes (THP1 cells) by flow cytometry. The methanol extract of leaves of Feretia apodanthera and the chloroform extract of roots of Guiera senegalensis exhibited a pronounced antimalarial activity. Two alkaloids isolated from the active extract of Guiera senegalensis, harman and tetrahydroharman, showed antimalarial activity (IC(50) lower than 4 microg/mL) and displayed low toxicity against THP1. Moreover, the decrease of THP1 cells in S phase of the cell cycle, after treatment with harman and tetrahydroharman, was probably due to an inhibition of total protein synthesis.

Deciphering Arabidopsis thaliana gene neighborhoods through bibliographic co-citations.

In the framework of genome annotation, scientific literature is obviously the major source of biological knowledge. The aim of the work described in this paper is to exploit this source of data for the model plant Arabidopsis thaliana. The first step has consisted in constituting a relevant bibliographic references dataset for plant genomic research. Genes co-citations have then been systematically annotated in this reference dataset, starting from the simple idea that if genes are cited in the same publication, they must probably share some related functional properties. In order to deal with the synonymous gene name problem, a gene name reference list has been constituted starting from A. thaliana SwissProt entries. This list was used to build clusters of co-cited genes by a single linkage procedure such that any gene in a given cluster possesses at least one co-cited partner in the same cluster. Analysis of the clusters demonstrate the biological consistency of this approach, with only very few fortuitous links. As an example, a cluster including genes related to flowering time is more deeply described in the paper. Finally, a graphical representation of each cluster was performed, which provides a convenient way to retrieve the genes (the nodes of the graphs) and the references in which they were co-cited (the edges of the graphs). All the results can be accessed at the URL http://chlora.Igi.infobiogen.fr:1234/bib_arath/.

Massive sequence comparisons as a help in annotating genomic sequences.

An all-by-all comparison of all the publicly available protein sequences from plants has been performed, followed by a clusterization process. Within each of the 1064 resulting clusters-containing sequences that are orthologous as well as paralogous-the sequences have been submitted to a pyramidal classification and their domains delineated by an automated procedure à la. This process provides a means for easily checking for any apparent inconsistency in a cluster, for example, whether one sequence is shorter or longer than the others, one domain is missing, etc. In such cases, the alignment of the DNA sequence of the gene with that of a close homologous protein often reveals (in 10% of the clusters) probable sequencing errors (leading to frameshifts) or probable wrong intron/exon predictions. The composition of the clusters, their pyramidal classifications, and domain decomposition, as well as our comments when appropriate, are available from http://chlora.infobiogen.fr:1234/PHYTOPROT.

Structure and antiprotozoal activity of triterpenoid saponins from Glinus oppositifolius.

Two new triterpenoid saponins, glinosides A and B, isolated from the aerial parts of Glinus oppositifolius, have been characterized by 1D, 2D, NMR and high-resolution mass spectral (HRMS) techniques. Their structures were established respectively as 16-O-(beta-arabinopyranosyl)-3-oxo-12,16 beta,21 beta,22-tetrahydroxyhopane for glinoside A and 16-O-(beta-arabinopyranosyl)-3-oxo-12,16 beta,22-trihydroxyhopane for glinoside B. Results presented evidence that fractions had a better antiplasmodial activity (IC50 = 31.80 micrograms/ml) than pure glinoside A (IC50 = 42.30 micrograms/ml).

Constituents of Ipomoea fistulosa leaves.

The isolation of flavonol glycosides 1-3 from the leaves of Ipomoea fistulosa is reported.

Antimalarial activity of four plants used in traditional medicine in Mali.

Mitragyna inermis (De Willd.) O. Kuntze Rubiaceae, Nauclea latifolia (Sm.) Rubiaceae, Glinus oppositofolius (Linn) Molluginaceae and Trichilia roka (Forsk.) Chiv. Meliaceae were investigated for their in vitro antimalarial activity. Leaves, roots and stem barks were submitted to aqueous, hydromethano and chloroform extractions and antimalarial activity was evaluated by microscopic and flow cytometric analysis. The results present evidence that the alkaloids contained in chloroform extracts and ursolic acid, purified from the hydromethanol extract of M. inermis induced a significant decrease of parasite proliferation. However, aqueous extracts, traditionally used for medication did not show high antimalarial activity. Statistical comparison between microscopic and cytometric analysis demonstrated the validity of this new technique for the screening of active antimalarial compounds isolated from plants.

Antiprotozoal activity of sesquiterpenes from jasonia glutinosa.

Two sesquiterpene alcohols, [11 R]-eudesm-4(14)-en-5ß,11,12-triol ( 1 ) and [11R]-eudesm-4(14)-en-5a,11-12-triol ( 2 ), from Jasonia glutinosa aerial parts (Asteraceae), have been tested using an in vitro technique against Leishmania donovani (promastigote forms) and Plasmodium falciparum . Sesquiterpene 1 was not effective at the assayed concentrations. Sesquiterpene 2 was found to be active against Leishmania donovani and Plasmodium falciparum .

Codon usage as a tool to predict the cellular location of eukaryotic ribosomal proteins and aminoacyl-tRNA synthetases.

In spite of many efforts, the prediction of the location of proteins in eukaryotic cells (cytoplasm, mitochondrion or chloroplast) is still far from straightforward. In some cases (e.g. ribosomal proteins and aminoacyl-tRNA synthetases) both the cytoplasmic proteins and their organellar counterparts are encoded by the nuclear genome. A factorial correspondence analysis of the codon usage in yeast and Caenorhabditis elegans shows that the codon usage of those nuclear genes encoding ribosomal proteins or aminoacyl-tRNA synthetases is markedly different, depending on the final location of the proteins (cytoplasmic or mitochondrial). As a consequence, the location of such proteins-whose sequences are now frequently determined by systematic genomic sequencing-can be easily and quickly predicted. A WWW interface has been developed, aimed at providing a user-friendly tool for codon usage pattern analysis. It is available from http://www.genetique.uvsq.fr/afc.html