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Estudos hematológicos e caracterização estrutural e funcional das hemoglobinas do peixe pulmonado Lepidosiren paradoxa (Dipnoi, Fitzinger, 1837) e do peixe de respiração aérea facultativa Hoplerythrinus unitaeniatus (Characiformes, Spix, 1829)
(Universidade Federal de São Carlos, 2011-08-01) Silva, Hugo Ribeiro da; Fernandes, Marisa Narciso; https://lattes.cnpq.br/3021357484136942
The blood cell composition in their qualitative and quantitative aspects as well as the functional properties of hemoglobin (Hb) shows characteristic of adaptation to the aquatic environment, aiding the understanding of the adaptability of the fish to the environment. The present study aimed to analyze the peripheral blood cells and the structural and functional characterization (in vitro) of hemoglobins of the South American lungfish, Lepidosiren paradoxa and facultative air-breathing fish H. unitaeniatus collected nearby Cuiaba, MT. The hematological variables, blood cell size, plasma ions, glucose and protein concentrations and the osmolality as well as the electrophoretic patterns of Hbs, the Root effect, quantification and the effect of allosteric modulators (IHP, ATP, GTP, 2.3 - BPG and NaCl) of the affinity of Hb to oxygen and Hb affinity in experiments of oxygenation in the blood stripped to and 4oC, 21oC and 40oC. The blood cells of L. paradoxa are exceptionally large and not numerous compared to H. unitaeniatus. The hematocrit and blood pH were similar in the two species. The erythrocyte number was lower in L. paradoxa (52 .103 ± 17 L-1) than in H unitaeniatus (2386 .103 ± 370 L-1). The hematimetric indexes mean corpuscular volume and mean corpuscular Hb were higher in L. paradoxa while the mean corpuscular Hb concentration and Hb concentration were higher in H. unitaeniatus. Among the white blood cells, in L. paradoxa, the lymphocytes (65.00 ± 4.00 %) were the most frequent cells, followed by eosinophils (19.00 ± 3.00 %), neutrophils (12.00 ± 2.00 %), monocytes (2.00 ± 0.60 %) and basophils (1.40 ± 0.40 %). In H. unitaeniatus lymphocytes were also the most frequent cells (85.14 ± 3.21 %) followed by neutrophils (12.00 ± 3.00 %) and monocytes (2.90 ± 1.23 %). In L. paradoxa the Mg+2, glucose and total protein plasma levels were significantly smaller than in H. unitaeniatus. There were no significant differences in the levels of K+, Ca+2, Cl- and osmolarity of plasma and between both species. Two Hb components, one major and another minor band was identified in L. paradoxa and another smaller; in H. unitaeniatus 6 anode components being 3 slow components and 3 fast component have been identified at different concentrations. In both species the stripped Hbs in three temperatures and in the presence of modulators, showed normal Bohr effect. In L. paradoxa cooperatively values were near 2.00 indicating cooperatively and absence of effect of Root; in H. unitaeniatus the cooperatively values were near 1.50, indicating low cooperatively and presence of Root effect. The affinity of Hb-oxygen proved be higher as decreased the temperature. The 2.3 - BPG was little effective in modulate the Hb in both species. The IHP ATP, GTP, and NaCl acted as negative modulators, being more effective in the modulation of Hb of H. unitaeniatus. The 2.3 - BPG was not detected in H. unitaeniatus and the ATP was the primary nucleotide intraeritrocitário for the two species being approximately 2 times higher than the GTP. In L. paradoxa was detected small amount IP2, but not in H. unitaeniatus. Our results show marked differences between the blood cells of L. paradoxa and H. unitaeniatus and the ability of adaptation of Hbs to environmental conditions to which they living.
Precessão Livre de Onda Contínua (CWFP) como ferramenta para supressão do sinal de solvente em RMN de alta resolução
(Universidade Federal de São Carlos, 2011-08-01) Duarte, Claudimar Junker; Venâncio, Tiago; https://lattes.cnpq.br/4438399441102990; https://lattes.cnpq.br/8065086767122141
The application of Continuous Wave Free Precession (CWFP) method for solvent suppression in high resolution NMR spectroscopy is reported. The applied methodology was based in the use of conventional pulse sequence that use a train of pulses with same phase, intensity and duration, separated by a time interval (Tp) shorter than the longitudinal (T1) and transverse (T2) relaxation times of the sample. After that, it was performed modifications that correspond to the phase alternation of pulses. These modifications allowed to minimize phase anomalies, which result from the refocusing of the magnetization and occur in the 1H spectrum when using the conventional pulse sequence. Through the new sequence, named PA-CWFP, it was possible to suppress solvent signals in several samples with different characteristics and the determination of sucrose content in four different types of grapes (Vitis vinifera), available in the local trade. In addition, the train of pulses with phase alternation was added in two routines 2D experiments: COSY (Correlation Spectroscopy) and HMBC (Heteronuclear Multiple-Bond Correlation Spectroscopy). The results were compared with traditional sequences for solvent suppression and demonstrate the potential of Continuous Wave Free Precession method for experiment of this type.
Isomerização do n-Hexano por platina suportada na zeólita H-ZSM-5 : efeito do teor de alumínio
(Universidade Federal de São Carlos, 2011-08-01) Gomes, Fagner Alves; Cardoso, Dilson; https://lattes.cnpq.br/2462847535959232; https://lattes.cnpq.br/2587990892434114
The objective of this study was to verify the influence of the Si/Al ratio (11.5, 15.0, 25.0, 40.0 and 140.0) in zeolite ZSM-5 in the conversion, activity, selectivity and stability as bifunctional catalysts (Pt/H-ZSM-5) applied to the isomerization reaction of n-hexane. To prepare the bifunctional catalysts, initially the zeolites were submitted, successively, to ion exchange with ammonium cations, ion exchange cations with platinum, calcination and activation process. From the results of the isomerization of n-hexane, it was observed that with the increase of the Si/Al ratio, that is, decreasing the amount of aluminum, there was a reduction in activity and conversion. This is due to decrease the number of acid sites present, responsible to isomerize the carbocation generated in these sites. In contrast, the increase of the Si/Al ratio leads to a better selectivity to the formation of isomers. Among the catalysts, the Pt/H-ZSM-5 (15.0) showed the best result of conversion and activity. In order to compare the Pt/H-ZSM-5 catalysts, the reaction was carried out using the isomerization catalyst Pt/H-Beta (9.0). This catalyst had the best result that all the others, this result may possibly be due to increased acidity of the material and its morphological characteristics, such as type and diameter of pores etc. and/or the crystallite size of zeolites used.