ABSTRACT
To explore the potential mechanisms underlying the effects of a probiotic in cirrhotic patients, we analyzed the blood metabolome using proton nuclear magnetic resonance (1H-NMR) spectroscopy in 32 patients with cirrhosis and cognitive dysfunction or falls. Patients were randomized to receive a multistrain probiotic or placebo for 12 weeks. Among the 54 metabolites identified, the only significant changes in the probiotic group were an increase in glutamine, a decrease in glutamate, and an increase in the glutamine/glutamate ratio. In the placebo group, glutamate increased and the glutamine/glutamate ratio decreased. Our results suggest the multistrain probiotic could influence glutamine/glutamate metabolism, increasing the capacity of ammonia detoxification.
Subject(s)
Glutamine , Probiotics , Humans , Glutamine/metabolism , Glutamic Acid/metabolism , Metabolomics/methods , Liver Cirrhosis , Probiotics/therapeutic useABSTRACT
Cytokine-induced inflammation and mitochondrial oxidative stress are key drivers of liver tissue injury. Here, we describe experiments modeling hepatic inflammatory conditions in which plasma leakage leads to large amounts of albumin to reach the interstitium and parenchymal surfaces to explore whether this protein plays a role in preserving hepatocyte mitochondria against the damaging actions of the cytotoxic cytokine tumor necrosis factor alpha (TNFα). Hepatocytes and precision-cut liver slices were cultured in the absence or presence of albumin in the cell media and then exposed to mitochondrial injury with the cytokine TNFα. The homeostatic role of albumin was also investigated in a mouse model of TNFα-mediated liver injury induced by lipopolysaccharide and D-galactosamine (LPS/D-gal). Mitochondrial ultrastructure, oxygen consumption, ATP and reactive oxygen species (ROS) generation, fatty acid ß-oxidation (FAO), and metabolic fluxes were assessed by transmission electron microscopy (TEM), high-resolution respirometry, luminescence-fluorimetric-colorimetric assays and NADH/FADH2 production from various substrates, respectively. TEM analysis revealed that in the absence of albumin, hepatocytes were more susceptible to the damaging actions of TNFα and showed more round-shaped mitochondria with less intact cristae than hepatocytes cultured with albumin. In the presence of albumin in the cell media, hepatocytes also showed reduced mitochondrial ROS generation and FAO. The mitochondria protective actions of albumin against TNFα damage were associated with the restoration of a breakpoint between isocitrate and α-ketoglutarate in the tricarboxylic acid cycle and the upregulation of the antioxidant activating transcription factor 3 (ATF3). The involvement of ATF3 and its downstream targets was confirmed in vivo in mice with LPS/D-gal-induced liver injury, which showed increased hepatic glutathione levels, indicating a reduction in oxidative stress after albumin administration. These findings reveal that the albumin molecule is required for the effective protection of liver cells from mitochondrial oxidative stress induced by TNFα. These findings emphasize the importance of maintaining the albumin levels in the interstitial fluid within the normal range to protect the tissues against inflammatory injury in patients with recurrent hypoalbuminemia.
Subject(s)
Albumins , Liver Diseases , Tumor Necrosis Factor-alpha , Animals , Mice , Albumins/metabolism , Apoptosis , Cytokines/metabolism , Hepatocytes/metabolism , Lipopolysaccharides , Liver/metabolism , Liver Diseases/metabolism , Mitochondria/metabolism , Oxidative Stress , Reactive Oxygen Species/metabolism , Tumor Necrosis Factor-alpha/pharmacologyABSTRACT
This work presents a comparison between an environmental impact assessment (EIA) and a life cycle assessment (LCA) using a case study: upgrading of biogas. The upgrading of biogas is studied using three solvents: water, physical solvent and amine. The EIA follows the requirements of the legislation of Santa Fe Province (Argentina), and the LCA follows ISO 14040. The LCA results showed that water produces a minor impact in most of the considered categories whereas the high impact in the process with amines is the result of its high energy consumptions. The positive results obtained in the EIA (mainly associated with the cultural and socioeconomic components) make the project feasible and all the negative impacts can be mitigated by preventive and remedial measures. From the strengths and weaknesses of each tool, it is inferred that the EIA is a procedure that can complement the LCA.
Subject(s)
Biofuels , Carbon Dioxide/isolation & purification , Environment , Methane/chemical synthesis , Water Pollutants, Chemical/isolation & purification , Water Purification/methods , Argentina , Carbon Dioxide/chemistry , Computer Simulation , Environmental Monitoring/methods , Models, Theoretical , Solvents/chemistry , Water Pollutants, Chemical/chemistryABSTRACT
Amastigotes from L. (L.)amazonensis (La), L. (L.)venezuelensis (Lv), L. (V.)brasiliensis (Lb), and L. (L.)chagasi (Lch) were cultured in a free cells liquid culture medium. Patients (n = 87) from a cutaneous leishmaniasis (CL) hyperendemic region receiving different treatments were followed up from January 1994 to August 2000. Time for remission of lesions were spontaneous remission (SR) 7 weeks; Glucantime (Glu) chemotherapy 9 weeks; immunotherapy with La, Lv, Lb, and Lch amastigotes Tosyl-Lysil Chloromethyl-ketone (TLCK) treated and Nonidet P-40(NP-40) extracted (VT) 7 weeks. Delayed type hypersensitivity (DTH) response with leishmanine intradermic reaction (IDR) was higher in CL patients than healthy controls (P < 0.05) and increased in active secondary versus primary infection (P < 0.001) with diagnostic value 1.74 for active infection and 1.81 postclinical remission. Antibodies to amastigotes characterized by Enzyme Linked Immunosorbent Assay (ELISA) decreased in sera postclinical remission versus active infections (P < 0.001), with a diagnostic value from 1.50 to 1.84. Immunoblottings antigenic bands frequency as well as Integral Optical Density (IOD) Area Densitometry decreased with sera from SR, after Glu or VT treatments in CL volunteers. Intracellular parasitism is due to normal antibodies recognizing parasite antigens after inoculation by vector. VT vaccine induced mainly cellular immunity, for remission of lesions and protection from CL infection.
ABSTRACT
The "Natural Killer" cells play an important roll in the immune response to tumoral cells and viral infections, and also they particpate in the rejection processes in allogeneic bone marrow transplantation. The interaction of natural killer cells and their receptors, with special reference to human diversity in killer cell inhibitory receptor genes, are described in this article with consideration to a normal Argentine population
Subject(s)
Rabbits , Killer Cells, Natural , Polymorphism, Genetic/genetics , Chromosomes, Human, Pair 19/geneticsABSTRACT
The "Natural Killer" cells play an important roll in the immune response to tumoral cells and viral infections, and also they particpate in the rejection processes in allogeneic bone marrow transplantation. The interaction of natural killer cells and their receptors, with special reference to human diversity in killer cell inhibitory receptor genes, are described in this article with consideration to a normal Argentine population
Subject(s)
Rabbits , Killer Cells, Natural , Chromosomes, Human, Pair 19 , Polymorphism, Genetic/geneticsABSTRACT
Se aislan y se caracterizan los antigenos de la superficie y los antigenos excretados al medio de cultivo por T.cruzi y T.rangeli, cultivados entre 26§ y 34§C en medios químicamente definidos, donde estos parásitos crecen sin suplemento proteico alguno. T.cruzi muestra 25-30 proteínas en su superficie, siendo las más concentradas las de 107,95,80,77,55,49,47 kDa de peso molecular, no encontrándose variación en el patrón electroforético en SDA-acrimilamida en las distintas cepas, como tampoco a las diversas temperaturas de cultivo. T.rangeli presenta 10-11 proteínas en su superficie, siendo las de mayor concentración a 26§C las correspondientes a 115,106,88,63,50 y 38 kDa, mientras que a 30§C, estas mismas bandas más las correspondientes a 76,57 y 53 kDa predominan sobre las demás. T.cruzi excreta 2 proteínas, una con un peso molecular de 83 kDa y otra cuyo peso molecular abarca un rango de 64 a 76 kDa. La separación de estas proteínas por isoelectroenfoque permite visualizar 12 bandas proteícas con puntos isoeléctricos entre 4,72 y 5,51 con un mayor número de bandas a 34§C que a 26§C, siendo el patrón igual en todas las cepas estudiadas en este trabajo. Al separar las bandas de proteínas onservadas en el isoelectroenfoque madiante cromatografía en DEAE-Sephadex, se observaron 10-15 especies proteícas en cada fracción de la columna, locual permite concluir que el T. cruzi excreta entre 100-150 proteínas de puntos isoeléctricos diferentes. Los sueros de pacientes chagásicos poseen un grupo de anticuerpos que reconocen a las proteínas de superficie de T. cruzi y otros grupos de anticuerpos que reconocen a las proteínas..
Subject(s)
Rats , Animals , Chagas Disease/diagnosis , Enzyme-Linked Immunosorbent Assay , Trypanosoma cruzi/isolation & purification , Trypanosoma/immunology , Trypanosoma/pathogenicity , Trypanosomiasis/diagnosisABSTRACT
Se presenta un medio de cultivo sintético suplementado con péptidos de bajo peso molecular que permite el crecimiento del Trypanosoma cruzi en la forma de epimastigotes entre 26 grados y 37 grados C. El análisis de los requerimientos nutritivos del parásito en este medio de cultivo revela que 9 aminoácidos son esenciales en el medio suplementado con suero fetal bovino o con péptidos desde el primer pasaje a todas las temperaturas, mientras que otros aminoácidos o sus precursores fueron necesarios para permitir el crecimiento después de un segundo pasaje. Cuando la temperatura de crecimiento fue entre 30-37 grado C también fueron necesarios 5 aminoácidos: B-alamina, glutamina, cisteína, ornitina y treonina. Nueve vitaminas fueron necesarias a todas las temperaturas que el ácido ascórnico y el ergocalciferol no se necesitaron en ningún caso. El resto de los aminoácidos y de las vitaminas variaron su papel de factor de crecimiento dependiendo de la temperatura de incubación del medio de cultivo. en el caso de los medios de cultivo suplementados con péptidos, aumentaron en forma ostensible al compararlos con los medios suplementados con proteínas. Un péptido compuesto por un ácido glutámico, dos alaninas y una lisina puede substituir como factor de crecimiento al suero fetal bovino a todas las temperaturas. Se han preparado medios de cultivo mínimo donde epimastigotes de T. cruzi pueden crecer entre 26 y 37 grados C por más de 30 pasajes
Subject(s)
Animals , Culture Media , Trypanosoma cruzi/enzymologyABSTRACT
Hemos desarrollado un medio de cultivo libre de proteinas y se contiene sales, glucosa, D-ribosa, 2-deoxyribosa, hemina, tricina, HEPES, 34 aminoácidos, 23 vitaminas, 6 nucleótidos y ácido tetrahidrofólico, donde 17 cepas de Leishmanias pertenecientes a 4 especies: brasiliensis, mexicana, donovani y garnhami crecen en forma continua a 26 grados C. Las distintas especies presentan una variabilidad muy grande en cuanto a requerimientos nutritivos se refiere, lo cual nos ha llevado a preparar medios minimos químicamente definidos para cada subespecie de Leishmania. La virulencia de los parasitos en estos medios se mantiene después de 30 pasajes en el medio definido. Los requimientos para la diferenciación en amastigotes también cambian según las especies de Leishmanias y varia en función de la temperatura del medio de cultivo así como del contenido proteico del mismo. Los péptidos trípticos obtenidos de la albúmina sérica bovina sustituyen al suero fetal bovino como factor de crecimiento entre 30-34 grados C
