92 research outputs found

    Equipartition of energy for the wave equation associated to the Dunkl-Cherednik Laplacian

    Full text link
    This paper is concerned with energy properties of the wave equation associated to the Dunkl-Cherednik Laplacian. We establish the conservation of the total energy, the strict equipartition of energy under suitable assumptions and the asymptotic equipartition in the general case.Comment: nombre de pages

    A rapid and easy method for the DNA extraction from Cryptococcus neoformans

    Get PDF
    DNA isolation from C. neoformans is difficult due to a thick and resistant capsule. We have optimized a new and rapid DNA isolation method for Cryptococcus using a short urea treatment followed by a rapid method using a chelex resin suspension. This procedure is simpler than previously reported methods

    Atividade moluscicida e larvicida das partes aéreas de Atriplex inflata contra o molusco Galba truncatula, hospedeiro intermediário da Fasciola hepatica

    Get PDF
    Fasciolose é uma parasitose generalizada que ocorre em animais de fazendas em muitos países em desenvolvimento. Por esta razão, é necessária a busca de novas substâncias contra as doenças parasitárias causadas por vermes. De fato, uma grande variedade de plantas terrestres foi objeto de testes farmacológicos e químicos a fim de descobrir o seu potencial para utilização em terapêutica humana. As atividades moluscicida e larvicida de Atriplex inflata foram testadas contra estágios larvários de Galba truncatula e Fasciola hepatica infectando este caracol na Tunísia. Testes fitoquímicos foram realizados com extratos a fim de estabelecer uma relação significativa com as atividades moluscicida e larvicida. A atividade moluscicida foi avaliada submetendo os caracóis a soluções aquosas. Conforme o caso, hexano, acetato de etilo, metanol e metanol-água (8:2, v-v) foram utilizados como solventes de extração. Como resultado, hexano e extratos de acetato apresentaram atividades potentes de acordo com a Organização Mundial de Saúde, resultando em LC50 = 7,59 mg/L e 6,69 mg/L para extratos de hexano de folhas e frutos, respectivamente. Extratos de acetato de etilo resultaram em LC50 = 5,90 mg/L e 7,32 mg/L para as folhas e frutos sucessivamente. Atividades moluscicidas das substâncias sob a forma de pó foram menos potentes em caracóis, mas ativas de acordo com a Organização Mundial de Saúde. Hexano e extratos de acetato de folhas e frutos apresentaram atividade larvicida potente, com uma taxa de atraso superior a 45,50% (45,50-98,92%). Testes fitoquímicos mostraram que estas atividades podem ser atribuídas à presença de triterpenóides e/ou esteróis.Fasciolosis is a widespread parasitosis of farm live-stock in many developing countries. For this reason, it is necessary to search for new substances against parasitic diseases caused by flukes. Indeed, a wide variety of terrestrial plants have been subjected to chemical and pharmacological screening in order to discover their potential for human medicinal use. The molluscicidal and larvicidal activities of Atriplex inflata were tested on Galba truncatula and Fasciola hepatica larval stages infecting this snail in Tunisia. Phytochemical tests were conducted on extracts in order to establish a meaningful relationship with molluscicidal and larvicidal activities. The molluscicidal activity was evaluated by subjecting snails to sample aqueous solutions. Accordingly, hexane, ethyl acetate, methanol and methanol-water (8:2, v-v) were used as extraction solvents. As a result, hexane and ethyl acetate extracts showed potent activity, according to the World Health Organization, giving LC50 = 7.59 mg/L and 6.69 mg/L for hexane extracts of leaves and fruits, respectively. Ethyl acetate extracts gave LC50 = 5.90 mg/L and 7.32 mg/L for leaves and fruits, successively. Molluscicidal activities of powders were less potent on snails, but active according to the World Health Organization. Hexane and ethyl acetate extracts from leaves and fruits gave potent larvicidal activities with a delay rate exceeding 45.50% (45.50- 98.92%). Phytochemical tests showed that these activities may be attributed to the presence of triterpenoids and/or sterols

    Protective effect of Ruta Chalepensis L. extract on oxidative stress and liver-kidney function induced by polymicrobial sepsis in rats

    Get PDF
    Sepsis, a systemic inflammatory disease developed after an infectious insult and remains the major cause of death in intensive care units. The aim of this study was to examine the protective effect of the ethanolic extract of Ruta chalepensis L. (ERC) against oxidative stress and liver-kidney functions in cecal and ligation puncture (CLP) rats. In vitro, the results showed that ERC rich in phenolic compounds possessed important antioxidant activity. In vivo, CLP-induced oxidative stress evidenced by the increase of the TBARS and decrease in the enzymatic antioxidants (SOD, CAT, GPX) in liver and kidney. Moreover, CLP induced liver-kidney toxicities showed by an increase in the ALT, AST, PAL, LDH, BUN and creatinine in the plasma. However, the administration of ERC to CLP-rats prevents all these disorders. Positive action of ERC was confirmed by histo-pathological examination. Therefore this study suggests that ERC could be a potential therapeutic agent for sepsis treatment

    0528: The role of brain natriuretic peptide and cystatin C in the evaluation of left ventricular diastolic dysfunction: correlation with echocardio-graphic indexes after myocardial infarction

    Get PDF
    BackgroundThe utility of Brain Natriuretic Peptide (BNP) and cystatin C for detecting left ventricular (LV) diastolic dysfunction after myocardial infarction (MI) in patients without heart failure symptoms still unclear. In this study, we investigated the relation between BNP, serum cystatin C levels and LV diastolic dysfunction after MI in patients without systolic dysfunction.MethodsWe studied 127 patients without renal dysfunction after first acute coronary syndrome (ACS). LV diastolic function was assessed with conventional Doppler, by means of mitral inflow and with tissue Doppler echo-cardiography by means of mitral annulus. The ratio of early diastolic transmitral E wave velocities to tissue Doppler mitral annulus early diastolic E’ wave velocities (E/E’), was used to detect LV filling pressures. Patients were divided in three groups according to E/E’ ratios<10 (group I), E/E’ ratios “between” 10 and 15 (group II) and E/E’ ratios>15 (group III). Plasma concentrations of BNP and serum cystatin C were measured at admission.ResultsThe BNP and serum cystatin C levels were positively correlated significantly with E/E’ ratio (r=0.786, P<0.001 and r=0.458, p=0.02). Patients with elevated LV end diastolic pressure (LVEDP), defined as E/E’>15 had highest BNP (321±75pg/mL) and cystatin C (1.1±0.2mg/L) levels. E/E’ 10 to 15 group had a mean BNP level of 151±28pg/mL and a mean cystatin C value of 0.78±0.1mg/L, and those with E/E’<10 had a mean BNP value of 69±20pg/ mL. A BNP value of 89pg/mL had a sensitivity of 84% and a specificity of 69% for predicting E/E’>15.ConclusionThe assessment of the blood concentration of BNP and cystatin C is of potential value for identification of those patients after myocardial infarction to detect early cardiovascular changes, especially LV diastolic dys-function

    Different roles of heat shock proteins (70 kDa) during abiotic stresses in barley (Hordeum vulgare) genotypes

    Get PDF
    In this work, the involvement of heat shock proteins (HSP70) in barley (Hordeum vulgare) has been studied in response to drought and salinity. Thus, 3 barley genotypes usually cultivated and/or selected in Italy, 3 Middle East/North Africa landraces and genotypes and 1 improved genotype from ICARDA have been studied to identify those varieties showing the best stress response. Preliminarily, a bioinformatic characterization of the HSP70s protein family in barley has been made by using annotated Arabidopsis protein sequences. This study identified 20 putative HSP70s orthologs in the barley genome. The construction of un-rooted phylogenetic trees showed the partition into four main branches, and multiple subcellular localizations. The enhanced HSP70s presence upon salt and drought stress was investigated by both immunoblotting and expression analyses. It is worth noting the Northern Africa landraces showed peculiar tolerance behavior versus drought and salt stresses. The drought and salinity conditions indicated the involvement of specific HSP70s to counteract abiotic stress. Particularly, the expression of cytosolic MLOC_67581, mitochondrial MLOC_50972, and encoding for HSP70 isoforms showed different expressions and occurrence upon stress. Therefore, genotypes originated in the semi-arid area of the Mediterranean area can represent an important genetic source for the improvement of commonly cultivated high-yielding varieties

    Physiological and molecular osmotic stress responses in three durum wheat (Triticum turgidum ssp durum) genotypes

    Get PDF
    This study aims to investigate the activities and expression of enzymes of primary metabolism and relate these data with the growth performance of three dierent durum wheat genotypes (Maali; YT13; and ON66) under osmotic stress. Growth traits—including plant height, dry weight (DW) and relative water content (RWC)—were measured to classify genotypes depending on their tolerance to stress. Several enzymes were investigated: Ascorbate peroxidase (APX), Glutamine Synthetase (GS), Glutamine dehydrogenase (GDH), Glutamate synthase (GOGAT), Glucose 6-phosphate dehydrogenase (G6PDH), and Phosphoenolpyruvate Carboxylase (PEPC). The expression of the cytosolic and plastidic glutamine synthetase (TaGS1 and TaGS2), high anity nitrate transporters (TaNRT2.3) and Glutamate dehydrogenase (TaGDH) were also detected by qRT-PCR. The results indicated dierent growth performances among genotypes, indicating Maali and YT13 as tolerant genotypes and ON66 as a drought-susceptible variety. Data showed a decrease in PEPC and increase in APX activities under osmotic stress; a slight decrease in GS activity was observed, together with an increase in G6PDH in all genotypes; GS and NRT2 expressions changed in a similar pattern in the dierent genotypes. Interestingly, Maali and YT13 showed higher transcript abundance for GDH under stress compared to ON66, suggesting the implication of GDH in protective phenomena upon osmotic stress
    • …
    corecore