Enumeration and characterization of arsenic-tolerant diazotrophic bacteria in a long-term heavy-metal-contaminated soil

The abundance of arsenic-tolerant diazotrophic bacteria was compared in a long-term contaminated soil versus a non-contaminated one. In addition, the characterization of tolerant diazotrophic bacteria was carried out. Differences in the number of heterotrophic N2 fixers were found between soils. Contaminated soil showed a decrease in the microbial population size of about 80%, confirming the great sensitivity of this group of soil bacteria to metals. However, quantitative analysis of the response to increased doses of arsenic reveals that the proportion of the culturable diazotrophic community tolerant to arsenic was identical for both soils (contaminated and non-contaminated). Twentytwo arsenic-tolerant diazotrophic isolates were obtained and further characterized. 16S ribosomal DNA sequence analysis revealed that these bacterial isolates were distributed among four taxons (Actinobacteria, Firmicutes, γ-Proteobacteria, and β-Proteobacteria). Most genera recovered from the contaminated soil were also found in the uncontaminated soi

Potencial Antibacteriano De Plantas Nativas Do Bioma Caatinga Frente A Staphylococcus Spp.: Isolados De Mastite Em Pequenos Ruminantes

The aim of the present study is to assess the antibacterial potential of plants from the Caatinga biome of the semi-arid region of Pernambuco, against Staphylococcus spp. isolates from cases of subclinical mastitis in small ruminants, such as goats and ewes. Ethanolic extracts of the following plants from the Caatinga biome were used: Encholirium spectabile Mart., Bromelia laciniosa Mart., Neoglaziovia variegata Mez., Amburana cearensis (Fr. Allem.) A.C.Smith, Hymenaea martiana Hayne, and Selaginella convoluta Spring. The presence of phenolic components, flavonoids, steroids, and terpenoids was verified for all the tested extracts. The mean minimal bactericide concentrations of the extracts of E. spectabile, B. laciniosa, and N. variegate were 11,379, 11,405, and 11,995 μg/mL, respectively. The highest inhibitory activities were observed for A. cearensis and H. martiana, which inhibited 88.1 and 99.4% of the isolates, respectively. Other studies focusing on in vitro and in vivo activities should be undertaken. © 2016, Universidade Federal Rural do Semi-Arid. All Rights Reserved.29375876

Concomitant essential thrombocythemia with jak2 v617f mutation in a patient with chronic myeloid leukemia with major molecular response with imatinib and long-term follow-up

The association of chronic myeloid leukemia (CML) with other myeloproliferative neoplasms (MPNs), in particular with the V617F mutation in the Janus kinase 2 (JAK2) gene, is very uncommon, and there are only a few cases reported in the literature. In the present study, the case of a 73-year-old man with CML and persistent thrombocytosis, is reported. The patient achieved a complete cytogenetic response and major molecular response (MR) with imatinib. The patient presented JAK2 V617F mutation, and bone marrow morphology was consistent with essential thrombocythemia. The patient was treated with imatinib and hydroxyurea to control the platelet count, and maintains complete MR with imatinib upon 10 years of follow-up. Although rare, the association of breakpoint cluster region-Abelson rearrangement and JAK2 V617F mutation should be investigated in patients with MPN, since both genetic anomalies may be present at diagnosis or may emerge during treatment, and require different therapeutic approaches.The association of chronic myeloid leukemia (CML) with other myeloproliferative neoplasms (MPNs), in particular with the V617F mutation in the Janus kinase 2 (JAK2) gene, is very uncommon, and there are only a few cases reported in the literature. In the121485487sem informaçãosem informaçã

Single Mutations in Cytochrome P450 Oxidoreductase Can Alter the Specificity of Human Cytochrome P450 1A2-Mediated Caffeine Metabolism

Funding Information: F.E. and M.K.: UID/BIM/0009/2020 of the Portuguese Fundação para a Ciência e a Tecnologia (FCT) and HLTH-2022-STAYHLTH-02/grant agreement 101095679 of the European Horizon´s research and innovation program. Publisher Copyright: © 2023 by the authors.A unique cytochrome P450 (CYP) oxidoreductase (CPR) sustains activities of human microsomal CYPs. Its function requires toggling between a closed conformation enabling electron transfers from NADPH to FAD and then FMN cofactors and open conformations forming complexes and transferring electrons to CYPs. We previously demonstrated that distinct features of the hinge region linking the FAD and FMN domain (FD) modulate conformer poses and their interactions with CYPs. Specific FD residues contribute in a CYP isoform-dependent manner to the recognition and electron transfer mechanisms that are additionally modulated by the structure of CYP-bound substrate. To obtain insights into the underlying mechanisms, we analyzed how hinge region and FD mutations influence CYP1A2-mediated caffeine metabolism. Activities, metabolite profiles, regiospecificity and coupling efficiencies were evaluated in regard to the structural features and molecular dynamics of complexes bearing alternate substrate poses at the CYP active site. Studies reveal that FD variants not only modulate CYP activities but surprisingly the regiospecificity of reactions. Computational approaches evidenced that the considered mutations are generally in close contact with residues at the FD–CYP interface, exhibiting induced fits during complexation and modified dynamics depending on caffeine presence and orientation. It was concluded that dynamic coupling between FD mutations, the complex interface and CYP active site exist consistently with the observed regiospecific alterations.publishersversionpublishe

Deltamethrin to control the boll weevil

Estudou-se o efeito do deltamethrin nas formulações CE, FLOW, UBV e do Cypermethrin ED no controle ao bicudo-do-algodoeiro, Anthonomus grandis Boheman, 1843 (Coleoptera: Curculionidae), no município de Campina Grande, PB. O delineamento experimental foi o de blocos ao acaso, com quatro repetições e oito tratamentos, a saber: Deltamethrin, nas formulações Decis FLOW 50 SC) a 10 e 12,5 g i.a./ha; DECIS UBV 4 a 7,5; 10,0 e 12,5 g. i.a./ha; (Decis CE 25) a 12,5 g i.a./ha; Cypermethrin (Cymbush 30 ED bico branco) a 8,34 g i.a./ha e testemunha. Todos os tratamentos foram eficientes em manter a infestação ao redor do nível de controle, que é de 10% de botões atacados, até oito dias após a terceira pulverização. Altas populações podem ser reduzidas por três aplicações com intervalo de três dias.The effect of the EC, FLOW and ULV formulation of deltamethrin and cypermethrin ED on the cotton boll weevil Anthonomus grandis Boheman, 1843 (Coleoptera: Curculionidae) at Campina Grande, PB, Brazil, was studied. The randomized complete block design with four replications and eight treatments as folows was used: Deltamethrin (Decis FLOW 50 SC) 10 and 12,5 g a.i./ha; (Decis ULV) 7,5; 10,0 and 12,5 g a.i./ha; (Decis EC) 12,5 g a.i./ha; Cypermethrin (Cymbush 30 ED white nozzle) 8,34 g a.i./ha and check. All the treatments were efficient to maintain the square infestation around the action level, which is 10% of infested squares, up to eight days after the third application. High weevil density may be reduced by three insecticide applications at a three-day interval

The effect of pH on the simultaneous determination of Sulfamethoxazole and Trimethoprim by Ultraviolet Spectrophotometry and Multivariate Calibration

Analytical techniques based on Ultraviolet (UV) spectrophotometry are widely used in pharmaceutical analysis, because they are simple and inexpensive. The choice of pH is critical in the development of univariate methods for pharmaceutical quantitation by UV spectrophotometry since changes may modify the absorption spectrum profile. Similar to univariate methods by UV spectrophotometry changes in pH may influence the predictive ability of multivariate models, affecting the resultant analytical performance. We report herein on the influence of pH on the simultaneous determination of sulfamethoxazole (SMZ) and trimethoprim (TMP) in tablets using UV spectrophotometry and multivariate calibration. Data were recorded using a UV spectrophotometer in the wavelength range of 200 to 350 nm. The experimental matrix was constructed using 36 synthetic samples of SMZ-TMP mixtures. The concentration ranges used for the investigation were 14.0 to 26.0 mg L-1 for SMZ and 2.8 to 5.2 mg L-1 for TMP. The Partial Least Squares (PLS) regression models were generated with full-spectrum and multiple pH levels. At pH 4.3, lower values of relative standard error of prediction (RSEP %) for SMZ (1.83) and TMP (1.13) were obtained. The PLS model at pH 4.3 was used for the quantification of real samples (tablets obtained from 13 different manufacturers) and the results were compared with conventional procedures using high performance liquid chromatography (HPLC).

Physiological and biochemical responses to low non-freezing temperature of two Eucalyptus globulus clones differing in drought resistance

Abstract – We have compared the metabolic responses of leaves and roots of two Eucalyptus globulus L. clones CN5 and ST51 that differ in their sensitivity to water deficits (ST51 is more drought sensitive), with regard to the effect of chilling (10/5 ◦C, day/night). We studied changes in growth, osmotic potential and osmotically active compounds, soluble proteins, leaf pigments, and membrane lipid composition. Our data showed that both clones have the ability to acclimatize to chilling temperatures. As a result of 10 days of acclimation, an increase of soluble sugars in leaves of treated plants of both clones was observed that disappeared later on. Differences between clones were observed in the photosynthetic pigments and soluble protein content which were more stable in CN5 under chilling. It also was apparent that CN5 presented a less negative predawn water potential (ψpd) and a higher leaf turgor than ST51 throughout the chilling treatment. In the case of the CN5, increased total lipids (TFA) and concomitant increase of linolenic acid (C18:3) in leaves after acclimatization may be related to a better clone performance under chilling temperatures. Moreover, a higher constitutive investment in roots in the case of CN5 as compared to ST51 may benefit new root regeneration under low temperatures favoring growth after cold Mediterranean winter

Metastable liquid lamellar structures in binary and ternary mixtures of Lennard-Jones fluids

We have carried out extensive equilibrium molecular dynamics (MD) simulations to investigate the Liquid-Vapor coexistence in partially miscible binary and ternary mixtures of Lennard-Jones (LJ) fluids. We have studied in detail the time evolution of the density profiles and the interfacial properties in a temperature region of the phase diagram where the condensed phase is demixed. The composition of the mixtures are fixed, 50% for the binary mixture and 33.33% for the ternary mixture. The results of the simulations clearly indicate that in the range of temperatures $78 < T < 102 ^{\rm o}$K, --in the scale of argon-- the system evolves towards a metastable alternated liquid-liquid lamellar state in coexistence with its vapor phase. These states can be achieved if the initial configuration is fully disordered, that is, when the particles of the fluids are randomly placed on the sites of an FCC crystal or the system is completely mixed. As temperature decreases these states become very well defined and more stables in time. We find that below $90 ^{\rm o}$K, the alternated liquid-liquid lamellar state remains alive for 80 ns, in the scale of argon, the longest simulation we have carried out. Nonetheless, we believe that in this temperature region these states will be alive for even much longer times.Comment: 18 Latex-RevTex pages including 12 encapsulated postscript figures. Figures with better resolution available upon request. Accepted for publication in Phys. Rev. E Dec. 1st issu

Influence du système de conduite, lyre vs traditionnel, sur la physiologie et la productivité d’un cépage vigoureux

info:eu-repo/semantics/publishedVersio