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M Sanchez-Moreno

Publications and source records attributed to M Sanchez-Moreno.

At least 19 recordsLinked to original sources
PubMed1998

Proton nuclear magnetic resonance analysis of metabolic end products of the Bolivia strain of Trypanosoma cruzi and three of its clones.

Proton nuclear magnetic resonance (1H NMR) was used to study the in vivo metabolism of Trypanosoma cruzi, the pathogen causing American trypanosomiasis (Chagas' disease). Three clones were isolated from a strain of T. cruzi (Bolivia strain), The clones I, II and III and the original strain were characterized according to the spectra of their metabolic pathways to test the hypothesis that clonal evolution of T. cruzi has a major impact on biologically relevant properties of this parasite. T. cruzi (Bolivia strain) excreted acetate, alanine, glycerol, and succinate as major end products, in the proportion 6:4:2:2. Comparing the spectra of T. cruzi clones with the original Bolivia strain revealed both quantitative, as well as qualitative differences in the metabolites excreted: the clones I and II, as opposed to the Bolivia strain and clone III, excreted significant quantities of ethanol.

Acetates↗
PubMed1998

In vitro and in vivo activity of two Pt(IV) salts against leishmania donovani.

The activities of 8 platinum drug complex salts were determined against Leishmania donovani promastigotes. The three most active salts were selected: [PtIVBr6]H2 (pentamidine); [PtIVBr6]H2 (stilbamidine), and [PtIVCl6]H2 (2-piperazinyl(1) ethyl amine), which induced growth-inhibition rates of more than 50% at 24 h of treatment and at the maximum dosage tested. The cytotoxicity assays on the macrophage cell line J-774 showed high cytotoxicity for the salt [PtIVBr6]H2 (stilbamidine) with a percentage of specific 51Cr release of 58.2% at 24 h of incubation and 100 microg/ml. Meanwhile, assays of the other compounds showed practically no cytotoxicity. The salt [PtIVBr6]H2 (pentamidine) notably inhibited the incorporation of 3H-thymidine in the treated parasites. The ultrastructural alterations observed in the flagellates treated with the salts [PtIVCl6]H2 (2-piperazinyl(1)ethyl amine) and [PtIVBr6]H2 (pentamidine) suggest that both act preferentially at the nuclear level and at the kinetoplast-mitochondrion complex. Both compounds showed a high in vivo activity in parasitized Wistar rats.

Animals↗
PubMed1997

Induction of stress proteins in the plant trypanosome Phytomonas characias.

The present study of the synthesis of new proteins in plant trypanosomatids in the genus Phytomonas as a response to different types of stress demonstrates the production of a number of proteins that can be grouped into four families similar to those that appear in other organisms (heat-shock proteins). In the study of stress, Phytomonas cultures were subjected to changes in temperature from 22 degrees to 37 degrees C, deprived of glucose, grown in the presence of sodium arsenite, and treated with calcium ionophore. In addition, the culture medium was changed from Grace's medium (330 mosmol/1) to a plant-culture medium with an osmolarity of 286 mosmol/l, implying the exertion of stress during the parasite's normal biological cycle of passage from the insect vector to the plant host. The treatment with actinomycin D demonstrated that some of the mRNAs that codify these proteins are found in normal presynthesized conditions. To measure the effect of temperature on the macromolecule biosynthesis we compared the incorporation of labeled analogues ([3H]-thymidine, [3H]-uridine, and [3H]-leucine) by flagellates cultured at 22 degrees C with that by parasites cultivated at 37 degrees C.

Animals↗
PubMed1996

Activity and mode of action of acridine compounds against Leishmania donovani.

In the present work, we have assayed both the in vitro and in vivo action of two acridine compounds against Leishmania donovani. As part of this effort, we have studied the possible action mechanism of these compounds at the ultrastructural and biochemical levels and in relation to the synthesis of macromolecules. The two acridinones inhibit the in vitro growth of the promastigote forms of L. donovani at the highest concentration assayed (100 micrograms/ml). The in vivo results indicate that both compounds reduce the number of amastigotes per gram of spleen, and decrease parasitism, by more than 40%. With respect to the action mechanism, both compounds inhibit the incorporation of [3H]thymidine, inducing alterations at the ultrastructural level in the DNA and mitochondria. Alterations are also caused in the enzymes of the Krebs cycle.

Acridines↗
PubMed1996

Inhibition of superoxide dismutase from Ascaris suum by benzimidazoles and synthesized pyrimidine and glycine derivatives.

Copper-zinc superoxide dismutase was purified from Ascaris suum (Nematoda). Four benzimidazole derivatives, six recently synthesized pyrimidine derivatives and eleven recently synthesized glycine derivatives were shown to inhibit: (1) purified extracts of A. suum superoxide dismutase; (2) superoxide dismutase from host liver, and (3) purified extracts of superoxide dismutase from living A. suum incubated in the presence of these drugs. Thiabendazole compounds, with a documented effect against helminth parasites, were found to affect the superoxide dismutase. The inhibitory effects of some pyrimidine and glycine derivatives were higher than those of benzimidazoles, and the pyrimidine compounds failed to inhibit the host's enzyme. These derivatives are candidate anthelmintics, acting as inhibitors of certain metalloenzymes in parasites.

Analysis of Variance↗
PubMed1996

In vitro activity and biochemical effectiveness of new organometallic complexes of osmium(III) against Leishmania donovani and Trypanosoma cruzi.

In the present paper, the in vitro activities of 10 osmium(III) complexes with [OSIII(L)] degrees structure against promastigote forms of Leishmania donovani and epimastigote forms of Trypanosoma cruzi haven been assayed. The complexes OSIII-2,4dinitroimidazole dithiocarbamate, OSIII-4-nitroimidazole dithiocarbamate, OSIII-benznidazole dithiocarbamate and OSIII-2-amino-6-Br-benzothiazole dithiocarbamate induced high percentages of growth inhibition in the parasites. The four compounds showed moderate cell toxicity. The inhibitory effects of these complexes on macromolecule synthesis have been evaluated using [3H]-thymidine, [3H]-uridine and [3H]-leucine incorporation. These metal-drug complexes clearly inhibit the DNA, RNA and protein synthesis, as well as the enzymatic activities of succinate dehydrogenase, malate dehydrogenase and pyruvate kinase.

Animals↗
PubMed1995

Metabolic studies by 1H NMR of different forms of Trypanosoma cruzi as obtained by 'in vitro' culture.

By culturing Trypanosoma cruzi epimastigotes in modified Grace's medium with 10% foetal bovine serum, a significant quantity of metacyclic forms could be obtained. Transformation was observed after 8 days of culture, with metacyclic forms reaching 75%. Cultured Vero cells were infected with metacyclic forms and maintained until free-amastigote forms were obtained. Additionally, amastigote-like forms could be obtained by subjecting metacyclic cultures to heat shock. Parasites were grown with glucose as the major carbon source. The metabolites produced and excreted during culture were identified by difference proton nuclear magnetic resonance spectroscopy and quantified by enzymatic methods. The final products of glucose catabolism differed not only quantitatively but also qualitatively for the three major life-cycle stages of T. cruzi. The end products of metabolism produced by epimastigote forms were mainly acetate and pyruvate and, to a lesser extend, L-alanine and ethanol. Differences between epimastigotes and metacyclic forms were only quantitative. However, free amastigotes as well as amastigote-like forms, excreted acetate, glycerol, and pyruvate and to a lesser extent succinate, but no L-alanine or ethanol.

Animals↗
PubMed1995

Leishmania donovani: in vitro culture and [1H] NMR characterization of amastigote-like forms.

When Leishmania donovani promastigote forms, were cultured in TC-199 medium at 28 degrees C and subsequently incubated at 38 degrees C, they turned into aflagellate (amastigote-like) forms. A return of the incubation-culture temperature to 28 degrees C these amastigote-like forms to revert to promastigotes. The amastigotes obtained by heat-shock, were viable and retained antigenic capacity being recognized by the sera of naturally infected patients. These forms, remained also capable of multiplying inside the J-774A.1 macrophages. When the amastigote-like forms are kept in culture at 38 degrees C retained their rounded appearance and their biological characteristics for more than 3 months subculturing every 6 days. These amastigote-like forms, when used for subcultures at 28 degrees C, transformed into promastigotes capable of multiplying as flagellate forms. The amastigote-like forms obtained in vitro can be used in biochemical studies related to chemotherapy and immunology studies, as part of an effort to combat this parasite. The end-products of of glycolysis were studied in both the amastigote-like and promastigote forms of L. donovani, by proton magnetic resonance analysis of the culture media. Alanine, succinate, and acetate, were predominant, and to a lesser extent pyruvate, glycine and D-lactate. Our results suggest that both forms of Leishmania use different biochemical strategies to obtain their energy.

Animals↗
PubMed1995

Isolation, in vitro culture, ultrastructure study, and characterization by lectin-agglutination tests of Phytomonas isolated from tomatoes (Lycopersicon esculentum) and cherimoyas (Anona cherimolia) in southeastern Spain.

Plants of Lycopersicon esculentum (grown in greenhouses) and Anona cherimolia cultivated in southeastern Spain were examined for the presence of trypanosomatid flagellates. Kinetoplastid protozoa were found in the fruits but not in the phloem or other plant tissues. Parasites were detected from the onset of fruiting. Isolates were detected from the onset of fruiting. Isolates were adapted to in vitro culturing in monophase media. The form and the structural organization was studied by scanning and transmission electron microscopy. The parasites showed an ultrastructural pattern similar to that of other species of the genus Phytomonas. In tomatoes experimentally inoculated with flagellates cultivated in vitro, we observed that the parasites did not lose their infectious capacity. Three strains of trypanosomatids of the genus Phytomonas, isolated from different species of Euphorbia (E. characias and E. hyssopifolia) and from Cocos nucifera, were compared with our isolates by lectin-agglutination tests. Our isolates were different from the two strains isolated from Euphorbia, but with this technique we could not differentiate our isolates from those of the coconut, nor could we differentiate between the isolates, their ultrastructural similarity together with their similar behavior in the lectin-agglutination test suggesting that these isolates have a common origin.

Agglutination Tests↗
PubMed1994

Copper-zinc superoxide dismutase from Ascaris suum (Nematoda): purification and characterization.

Copper-zinc superoxide dismutase from Ascaris suum (Nematoda) was purified in a new, more efficient, and faster manner. The process included differential centrifugation, fractionation with ammonium sulfate, and sodium dodecyl sulfate-polyacrylamide electrophoresis, yielding a 340-fold purification (specific activity of 47 units/mg). Optimal storage conditions, optimal pH range, thermostability, molecular weight and ultraviolet-visible absorption spectrum of the enzyme are described, and a new enzymatic model for pharmacological screening is suggested.

Ammonium Sulfate↗
PubMed1992

Characterization of carbohydrate metabolism and demonstration of glycosomes in a Phytomonas sp. isolated from Euphorbia characias.

Phytomonas sp. isolated from Euphorbia characias was adapted to SDM-79 medium. Cells isolated in the early stationary phase of growth were analyzed for their capacity to utilize plant carbohydrates for their energy requirements. The cellulose-degrading enzymes amylase, amylomaltase, invertase, carboxymethylcellulase, and the pectin-degrading enzymes polygalacturonase and oligo-D-galactosiduronate lyase were present in Phytomonas sp. and were all, except for amylomaltase, excreted into the external medium. Glucose, fructose and mannose served as the major energy substrates. Catabolism of carbohydrates occurred mainly via aerobic glycolysis according to the Embden-Meyerhof pathway, of which all the enzymes were detected. Likewise, the end-products of glycolysis, acetate and pyruvate, glycerol, succinate and ethanol were detected in the culture medium, as were the enzymes responsible for their production. Mitochondria were incapable of oxidizing succinate, 2-oxoglutarate, pyruvate, malate and proline, but had a high capacity to oxidize glycerol 3-phosphate. This oxidation was completely inhibited by salicylhydroxamic acid. No cytochromes could be detected either in intact mitochondria or in sub-mitochondrial particles. Mitochondrial respiration was not inhibited by antimycin, azide or cyanide. The glycolytic enzymes, from hexokinase to phosphoglycerate kinase, and the enzymes glycerol kinase, glycerol-3-phosphate dehydrogenase, phosphoenolpyruvate carboxykinase, malate dehydrogenase and adenylate kinase, were all associated with glycosomes that had a buoyant density of about 1.24 g cm-1 in sucrose. Cytochemical staining revealed the presence of catalase in these organelles. The cytosolic enzyme pyruvate kinase was activated by fructose 2,6-bisphosphate, typical of all other pyruvate kinases from Kinetoplastida. The energy metabolism of the plant parasite Phytomonas sp. isolated from E. characias resembled that of the bloodstream form of the mammalian parasite Trypanosoma brucei.

Animals↗
PubMed1992

Superoxide dismutase from Trichuris ovis--inhibition by benzimidazoles and pyrimidine derivatives.

Three superoxide dismutase isoenzymes of different cellular location were detected in an homogenate of Trichuris ovis. Each of these molecular forms was purified by differential centrifugation and precipitation with ammonium sulphate, followed by chromatography on DEAE-cellulose and Sephadex G-75 columns. The activity levels of the two molecular forms detected in the mitochondrial (one cyanide sensitive Cu-Zn-SOD and the other cyanide insensitive Mn-SOD) were higher than that of the superoxide dismutase detected in the cytoplasmic fraction (cyanide sensitive Cu-Zn-SOD). All molecular forms present evident differences to the SODs contained in the host liver. Molecular mass and some of the physical and chemical properties of the enzyme was determined for all three molecular forms. An inhibitory effect on the SOD of the parasite an the host was detected with a series of compounds, some of which markedly inhibited parasite enzyme but not host enzyme.

Animals↗
PubMed1990

Electrophoretic analysis of gene-enzyme systems in Chabertia ovina.

In Chaberia ovina species an electrophoretic study of 15 loci of the following enzymes has been conducted: glucose phosphate isomerase, mannose phosphate isomerase, glucose-6-phosphate dehydrogenase, glutamate-oxaloacetate transaminase, superoxide dismutase, isocitrate dehydrogenase, hexokinase, adenylate kinase, malate dehydrogenase, malic enzyme, carbonic anhydrase and 6-phosphogluconate dehydrogenase. The genetic variability has been relatively high, with 40% polymorphism values noted, an 0.10 mean heterozygosity observed and an 0.17 mean heterozygosity expected. The greater part of the allele frequencies were not in Hardy-Weinberg equilibrium.

Alleles↗
PubMed1989

Superoxide dismutase in strains of the genus Flavobacterium: isolation and characterization.

Two electrophoretically different forms of superoxide dismutase, one of them containing manganese-protein and the other iron-protein, were detected in eleven different strains of the genus Flavobacterium. The activities of the different strains were similar to those described for other bacteria. The two molecular forms of the enzyme differed clearly with regard to activity, electrophoretic behaviour, sensitivity to cyanide and peroxide, and NaCl requirement. Both molecular forms were isolated from Flavobacterium halmephilum. Molecular mass absorption spectra, metal content, optimum pH, heat-sensitivity and stability were described.

Chromatography, DEAE-Cellulose↗
PubMed1989

Cu-Zn-superoxide dismutase activity in Moniezia expansa: inhibition by pyrimidine derivatives.

Copper-zinc, cyanide-sensitive superoxide dismutase (Cu-Zn-SOD) was detected in homogenates of Moniezia expansa. The enzyme was purified by a sequence of multiple differential centrifugations, ammonium sulphate precipitation, ion-exchange and G-75 Sephadex column chromatography. The final enzyme preparation had a specific activity of 623.00 +/- 9.97U per mg protein and, after isolation, a single-staining band on acrylamide-SDS gels was detected which coincided with enzyme activity. The inhibitory activities of several benzimidazoles and several novel pyrimidine derivatives were determined on purified extracts of the M. expansa Cu-Zn-SOD. The results indicated that the percentage inhibition of Cu-Zn-SOD by some pyrimidine derivatives (6-amino-1, 3-dimethyl-5-nitroso-uracil, 6-amino-5-methyl-5-nitroso-uracil and 5-amino-uracil) was markedly higher than inhibition with the benzimidazoles.

Animals↗
PubMed1989

Cellular distribution, purification and electrophoretic properties of malate dehydrogenase in Trichuris ovis and inhibition by benzimidazoles and pyrimidine derivatives.

High levels of malate dehydrogenase were found in Trichuris ovis. Two molecular forms of the enzyme, of different cellular location and electrophoretic pattern, were isolated and purified. The activity of soluble malate dehydrogenase was greater than that of mitochondrial malate dehydrogenase. Both forms also displayed different electrophoretic profiles in comparison with purified extracts from goat (Capra hircus) liver. Substrate concentration directly affected enzyme activity. Host and parasite malate dehydrogenase activity were both inhibited by a series of benzimidazoles and pyrimidine-derived compounds, some of which markedly reduced parasite enzyme activity, but not host enzyme activity. Percentage inhibition by some pyrimidine derivatives was greater than that produced by benzimidazoles.

Animals↗
PubMed1989

Isoenzyme patterns of phosphatases and esterases in Fasciola hepatica and Dicrocoelium dendriticum.

A study was made of alkaline and acid phosphatase isoenzymes and non-specific esterases in homogenates of the trematodes Fasciola hepatica and Dicrocoelium dendriticum obtained from infected tissues of Capra hircus and Ovis aries using horizontal polyacrylamide gel electrophoresis. The esterase patterns in F. hepatica and D. dendriticum were different. Homogenate of F. hepatica from both hosts gave four enzyme bands. For D. dendriticum, however, while homogenates of parasites from C. hircus also gave four bands, those of O. aries gave only three bands. Acid and alkaline phosphatases in homogenates of both parasites showed three enzyme bands, but there was a host species difference between the enzyme patterns of specimens collected from C. hircus versus O. aries.

Acid Phosphatase↗