Análises estomática e morfométrica de folhas de plantas diplóides e tetraplóides de Dendrobium nobile Lindl.

Este trabalho objetivou comparar plantas diplóides (2n=2x=38) e tetraplóides induzidos (2n=4x=76) de Dendrobium nobile Lindl., mediante análises estomática e morfométrica das folhas. Para a análise estomática, foram coletadas folhas completamente expandidas do terceiro nó, que foram submetidas aos procedimentos usuais em microtécnica vegetal para microscopia de luz e eletrônica de varredura. Foram avaliados a freqüência estomática, a freqüência das outras células epidérmicas, o índice estomático, os diâmetros polar e equatorial dos estômatos e a relação entre o diâmetro polar e o diâmetro equatorial. Para a análise morfométrica das folhas utilizadas nas análises estomáticas, foram avaliados a altura e o diâmetro do pseudobulbo e a largura e o comprimento das folhas. D. nobile apresentou estômatos elípticos, com laterais gradualmente inclinadas, sendo o tamanho dos estômatos inversamente proporcional ao nível de ploidia. As plantas poliplóides apresentaram menor crescimento quando comparadas com as diplóides. Portanto, foi possível distinguir plantas de D. nobile diplóides das plantas tetraplóides utilizando as análises estomática e morfométrica

Clinical oxidative stress during leprosy multidrug therapy:impact of dapsone oxidation

This study aims to assess the oxidative stress in leprosy patients under multidrug therapy (MDT; dapsone, clofazimine and rifampicin), evaluating the nitric oxide (NO) concentration, catalase (CAT) and superoxide dismutase (SOD) activities, glutathione (GSH) levels, total antioxidant capacity, lipid peroxidation, and methemoglobin formation. For this, we analyzed 23 leprosy patients and 20 healthy individuals from the Amazon region, Brazil, aged between 20 and 45 years. Blood sampling enabled the evaluation of leprosy patients prior to starting multidrug therapy (called MDT 0) and until the third month of multidrug therapy (MDT 3). With regard to dapsone (DDS) plasma levels, we showed that there was no statistical difference in drug plasma levels between multibacillary (0.518±0.029 μg/mL) and paucibacillary (0.662±0.123 μg/mL) patients. The methemoglobin levels and numbers of Heinz bodies were significantly enhanced after the third MDTsupervised dose, but this treatment did not significantly change the lipid peroxidation and NO levels in these leprosy patients. In addition, CAT activity was significantly reduced in MDT-treated leprosy patients, while GSH content was increased in these patients. However, SOD and Trolox equivalent antioxidant capacity levels were similar in patients with and without treatment. These data suggest that MDT can reduce the activity of some antioxidant enzyme and influence ROS accumulation, which may induce hematological changes, such as methemoglobinemia in patients with leprosy. We also explored some redox mechanisms associated with DDS and its main oxidative metabolite DDS-NHOH and we explored the possible binding of DDS to the active site of CYP2C19 with the aid of molecular modeling software

Nuclear effects on the transverse momentum spectra of charged particles in pPb collisions at √SNN = 5.02 TeV

Transverse momentum spectra of charged particles are measured by the CMS experiment at the CERN LHC in pPb collisions at [Formula: see text][Formula: see text], in the range [Formula: see text][Formula: see text] and pseudorapidity [Formula: see text] in the proton-nucleon center-of-mass frame. For [Formula: see text][Formula: see text], the charged-particle production is asymmetric about [Formula: see text], with smaller yield observed in the direction of the proton beam, qualitatively consistent with expectations from shadowing in nuclear parton distribution functions (nPDF). A pp reference spectrum at [Formula: see text][Formula: see text] is obtained by interpolation from previous measurements at higher and lower center-of-mass energies. The [Formula: see text] distribution measured in pPb collisions shows an enhancement of charged particles with [Formula: see text][Formula: see text] compared to expectations from the pp reference. The enhancement is larger than predicted by perturbative quantum chromodynamics calculations that include antishadowing modifications of nPDFs