Growth and production of cowpea beans under potassium doses in soil of cerrado in Amapá, Brazil.

The cowpea bean [Vigna unguiculata (L.) Walp.], a legume of great socioeconomic importance, it was previously cultivated exclusively for subsistence and commercial purposes, especially in the North and Northeast regions. This crop has a low production cost and high nutritional value, in addition to a high potential for productivity growth and expansion to other regions. The objective of this work was to evaluate parameters of growth and production in cowpea culture, as a function of potassium fertilization in soil of the cerrado of Amapá. The parameters of growth and production of the cowpea culture were evaluated, as a function of potassium fertilization in the soil of the cerrado of Amapá. The experiment was conducted in a greenhouse, using a completely randomized experimental design, with four replications, in a 5x2 factorial scheme, totaling 40 experimental units, which were composed of plastic pots containing 7 dm3 of soil collected from the arable layer (0-20 cm ) of a typical Hyperdystrophic Yellow Argisol, with a sandy clay loam texture, in a cerrado area in the municipality of Porto Grande-AP. The factors consisted of the control treatment (without K), four doses of K (45, 90, 135 and 180 kg ha-1) in the form of potassium chloride, and two cowpea cultivars (Pretinho and BRS Tumucumaque). The cultivar BRS Tumucumaque shows better growth and production of cowpea plants. Doses of 90 kg ha-1 provided greater height (98.75 cm) and stem diameter (10.0 mm). As for production, the dose of 135 kg ha-1 caused greater grain weight gain (5.25 g) and dry mass of pods (13.92 g), and the doses of 90 and 180 kg ha-1 induced greater number and length of pods (3.16 pods) respectively. These results show better responsiveness of the BRS Tumucumaque cultivar at doses of 90, 135 and 180 kg ha-1 in the type of soil where the study was conducted.

Assessment of the stability of sheep sausages with the addition of different concentrations of Origanum vulgare extract during storage.

The aim of this study was to assess the stability of sheep sausages with the addition of different concentrations of Origanum vulgare extract during storage. Five treatments were prepared: without natural antioxidant (control), sodium erythorbate 500mg/kg (ER), and three amounts of extract (N1=4964.51mg/kg, N2=6630.98mg/kg and N3=8038.20mg/kg). From appearance sensory analysis, control treatment differed significantly compared to ER (P<0.05) and N3 (P<0.01) groups, with intense red color, agreeing with trend of a* values. On the other hand, oregano extract improved the lipid and protein stability of cooked sausages during the storage time. Regarding volatile compounds from lipid oxidation, the N2 group presented the lowest values at the end of chilled period. In conclusion, the oregano extract showed antioxidant potential equivalent to sodium erythorbate at intermediate and high levels, calculated by DPPH∙ and FRAP methods, and most of the parameters were not compromised, allowing synthetic antioxidants replaced while maintaining the nutritional and sensory quality of cooked sausages.

Selection of maize inbred lines and gene expression for resistance to ear rot.

In recent years, there has been a large incidence of fungi causing "ear rot" in maize in Brazil, the main fungus being Fusarium verticillioides. The most efficient and competitive alternative for control of this disease consists of using maize hybrids resistant to this pathogen. Thus, the aims of this study were to analyze the genetic variability of maize inbred lines in regard to resistance to ear rot to observe if there is a maternal effect to resistance to ear rot, to study genetic control of the traits evaluated in hybrids originating from inbred lines of the maize breeding program at the Agriculture Department of Universidade Federal de Lavras (Lavras, MG, Brazil), and characterize the gene expression pattern related to the plant defense mechanism against F. verticillioides. High genetic availability was observed for resistance to this disease among the inbred lines evaluated. Considering combined diallel analysis, it was observed that the mean square of general combining ability (GCA) was not significant for the characteristic under study. However, specific combining ability (SCA) was significant, which indicates the predominance of non-additive effects involved in control of the characteristic for the population evaluated. A maternal effect was not observed for the characteristic of ear rot resistance in this study. Inbred lines 22, 58, and 91 showed potential for use in breeding programs aiming at resistance to F. verticillioides. Only two genes, LOX8 and Hsp82, had a satisfactory result that was able to be related to a plant defense mechanism when there is ear rot infection, though expression of these genes was observed in only one susceptible genotype. Thus, the genes LOX8 and Hsp82 are potential molecular markers for selection of maize inbred lines resistant to F. verticillioides.

Evaluation of oxidative stability of lamb burger with Origanum vulgare extract.

The objective was to evaluate replacement of sodium erythorbate with a natural antioxidant (oregano extract) on physicochemical and sensory stability of lamb burgers, and determine the appropriate amount. Five treatments were prepared, including control (without antioxidant), sodium erythorbate, and three concentrations of oregano extract (13.32, 17.79 and 24.01mL/kg), based on antioxidant capacity determined using the Folin-Ciocalteu, 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) methods, respectively. Burgers containing oregano extract, at the concentration determined by FRAP method, had higher oxidative stability, evidenced by an 80% reduction (P<0.001) in thiobarbituric acid reactive substances, effective inhibition of protein oxidation (P<0.01) and less colour loss during frozen storage. Oregano extract did not impair (P>0.05) consumers' sensory acceptance of the lamb burgers. Under the conditions tested, addition of 24mL/kg of oregano extract could be recommended as a natural antioxidant in lamb burgers.

Evaluation of antioxidant capacity of 13 plant extracts by three different methods: cluster analyses applied for selection of the natural extracts with higher antioxidant capacity to replace synthetic antioxidant in lamb burgers.

The aims of this study were: to evaluate the total equivalent antioxidant capacities (TEAC) and phenolic contents of 13 plants extracts; to select the most promising extracts regarding reducing activity using cluster analysis multivariate statistical technique; and to analyse evaluate sensory acceptance of lamb burgers produced with the most promising natural antioxidants replacing sodium erythorbate. Plant extracts were evaluated regarding TEAC by DPPH(•) and FRAP methods, and total phenolics contents by Folin-Ciocalteau assay. The TEAC values ranged from 0.50 to 9.06 g trolox/100 g dry weight (dw) and from 43.6 to 472.32 µmol trolox/g dw for DPPH(•) and FRAP methods, respectively, and the total phenolic contents from 5.98 to 74.01 mg GAE/g dw. Extracts from Origanum vulgare, Melissa officinalis, Origanum majorana L. and Rosmarinus officinalis were grouped as the ones with higher antioxidant capacities by cluster analysis. All burgers produced with each one of these four plant extracts or with sodium erythorbate showed no differences (P > 0.05) regarding consumers' sensory acceptance. In conclusion, it is possible to replace sodium erythorbate in lamb burgers by any of the four natural extracts selected without compromising sensory acceptance of this meat product.

Induction of oxidative stress in Prototheca zopfii by indole-3-acetic acid/HRP or 2,4-pentanedione/HRP systems and their oxidation products.

We investigated the toxic effects on Prototheca zopfii of indole-3-acetic acid (IAA) and 2,4-pentanedione (PD) combined with horseradish peroxidase (HRP) alongside the oxidation products of 3-methyl-2-oxindole (MOI) and indole-3-carbinol (I3C) from the IAA/HRP system and methylglyoxal (MGO) from the PD/HRP system. The microorganism was incubated in the absence (control) or presence of IAA, PD, IAA/HRP, PD/HRP, MOI, I3C and MGO and determined: (1) cytotoxicity by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium) assay; (2) growth inhibitory concentration by resazurin assay and (3) antioxidant enzymes activities of: catalase (CAT), glutathione reductase (GR) and superoxide dismutase (SOD). P. zopfii was more susceptible to IAA at 40 mM than PD at the same concentration, which seems to indicate that IAA was more effective at initiating cell death. These data corroborate results from the resazurin assay. Concentrations of 40 mM of IAA, IAA/HRP and PD/HRP, 20 mM of PD/HRP, 10 mM of MOI, 2 mM of I3C and 8 mM of MGO inhibited the growth of P. zopfii. With sub-inhibitory concentrations of IAA and IAA/HRP at 30 mM, MOI at 8 mM and I3C at 1 mM, the activities of CAT and GR increased, whereas no statistical difference was observed for CAT activity with IAA/HRP. Thus, PD at 30 mM and MGO at 6 mM increased the activities of CAT and GR, whereas PD/HRP system at 15 mM decreased CAT activity and PD/HRP and MGO showed no statistical difference for SOD activity. In conclusion, IAA/HRP or PD/HRP systems and their oxidation products exert cytotoxic effects on P. zopffi; however, I3C and MGO appear to exert greater microbicidal effect on P. zopfii.

Organic selenium supplementation increases PHGPx but does not improve viability in chilled boar semen.

This study evaluated the effects of dietary organic selenium (Se) on viability of chilled boar semen. Twelve boars were divided into three groups: control (CON), 0.3 mg kg(-1) sodium selenite; inorganic (INO), 0.5 mg kg(-1) sodium selenite and organic (ORG), 0.5 mg kg(-1) Se yeast. The experiment was conducted within 10 weeks, and analysis was performed fortnightly, in storage semen by 72 h. No effect was observed on motility; however, straightness and linearity percentages were higher (P < 0.05) in the animals receiving CON diet compared with INO group. Percentages of cells with both plasma and acrosomal intact membranes, lipidic membrane peroxidation and mitochondrial membrane potential were similar on all treatments. Animals receiving CON diet presented higher (P < 0.05) values of ATP when compared with INO group. The PHGPx was higher (P < 0.05) in animals that received ORG in comparison with INO group. In conclusion, organic selenium supplementation increases PHGPx but does not improve chilled semen viability in 72 h.

Efeito da suplementação de cobre e selênio na dieta de novilhos Brangus sobre o desempenho e fermentação ruminal / The effects of copper and selenium supplementation in the diet of Brangus steers on performance and rumen fermentation

Vinte e oito bovinos Brangus foram usados para determinar o efeito da suplementação de cobre e selênio no desempenho e na fermentação ruminal. Os animais foram divididos em: 1) C(Controle) - sem a suplementação de cobre e selênio; 2) Se - 2mg Se/kg de matéria seca na forma de selenito de sódio; 3) Cu - 40mg Cu/kg de matéria seca na forma de sulfato de cobre; 4) Se/Cu - 2mg Se/kg de matéria seca na forma de selenito de sódio e 40mg Cu/kg de matéria seca na forma de sulfato de cobre. As pesagens dos animais foram feitas em intervalos de 28 dias, após jejum completo de 18 horas. Foram colhidas amostras de líquido ruminal para análises de ácidos graxos voláteis e pH. O ganho de peso diário aumentou com a suplementação de Se (P<0,05). A ingestão de matéria seca não foi alterada pelos tratamentos (P>0,05). Os animais submetidos à suplementação com Cu apresentaram menor pH ruminal quando comparado com a suplementação Se/Cu (P<0,05). Os animais suplementados com Se/Cu apresentaram maior proporção de ácido acético quando comparado com o controle (P<0,05). Para o ácido propiônico e butírico, não houve diferenças significativas (P>0,05) entre os tratamentos. Apesar do pouco efeito na fermentação ruminal, as suplementações de selênio, cobre e selênio/cobre proporcionaram uma melhor eficiência alimentar.

Twenty-eight Brangus cattle were used to determine the effect of copper and selenium supplementation on performance and rumen fermentation. The animals were divided in: 1) (Control) - without supplementation of copper and selenium; 2) Se - 2mg Se/kg of dry matter as sodium selenite; 3) Cu - 40mg Cu/kg of dry matter as copper sulphate; 4) Se/Cu - 2mg Se/kg of dry matter as sodium selenite and 40mg Cu/kg of dry matter as copper sulphate. Animal weighing was performed in 28 day intervals, after 18 hours of fasting. Samples of rumen liquid were collected for analysis of volatile fatty acid and pH. The daily weight gain increased with selenium supplementation (P<0.05). The dry matter intake was not altered by treatments (P>0.05). The animals that received copper supplementation had lower pH rumen compared with selenium/copper supplementation (P<0.05). The animals supplemented with selenium/copper had a high proportion of acetic acid when compared to control (P<0.05). For propionic and butyric acid, there was no difference (P>0.05) among treatments. Despite the little effect on rumen fermentation, the supplementations of selenium, copper and selenium/copper provided better feed efficiency.

Changes in morphometric parameters of bone tissue due tophysical exercise: a systematic review

It is known that physical exercise can influence the morphometry of bone tissue. Thisinfluence depends on the intensity, frequency, duration and mode of exercise. However, these aspects arenot well described in literature. Futhermore, morphometric parameters for the study of bone tissue are moresuitable to investigate this effect. Given these uncertainties, we intend to investigate the effects of exercise inbone morphometry. Materials and methods: For this study, we performed a systematic search of articles inPUBMED, MEDLINE, OLD MEDLINE, SciELO and LILACS. We used the keywords: “morphometry”,“physical exercise” and “bone”. Results: Initially we found a total of 40 articles. Articles in which animalswere submitted to pharmacological or surgery intervention as well as those where rats had some disease orhormonal alteration were excluded. After selection according to inclusion and exclusion criteria, only threearticles remained. Discussion: Newhall, Kenneth, Marjoleine et al. (1991) investigated the effects of exercisein a non-systematic way, with no definitions of exercise parameters. It is suggested that various features ofphysical exercise, besides intensity, can influence on bone mechanical properties. The results of this researchshow the need to establish defined standards concerning the mode, intensity, frequency and duration ofexercise. Conclusion: It was not possible to determine which morphometric parameters are the best torepresent these changes. More studies in this area are suggested in order to comprehend the influence ofphysical exercise on bone tissue.

Effect of Cysticercus cellulosae on neutrophil function and death.

Neutrophils, eosinophils and macrophages interact with invading parasites and naive hosts. The initial reaction of leukocytes is the generation of reactive oxygen species (ROS). The cytotoxic effects of extracts derived from intact Cysticercus cellulosae and from the scolex or membrane fractions on neutrophils were examined. DNA fragmentation of neutrophils was observed when cells were incubated with an extract from the intact metacestode; however, the addition of antioxidant enzymes to the incubation medium had a protective effect. The scolex and membrane extracts did not affect DNA fragmentation of neutrophils. Hydrogen peroxide production of neutrophils incubated with metacestode fractions from C. cellulosae increased by 190% (total extract), 120% (scolex) or 44% (membrane). An increase in antioxidant catalase activity (28%) concomitant with the increased production of ROS was observed in neutrophils incubated with metacestode fractions, which could be an attempt at self-protection. ROS production by neutrophils in the presence of the intact cysticerci extract did not alter phagocytosis. In contrast, the scolex and membrane fractions increased the phagocytic capacity of neutrophils by 44 and 28%, respectively. The results showed that the extract from intact C. cellulosae was toxic for neutrophils via ROS production, leading to DNA fragmentation and inhibition of phagocytic capacity, but neutrophils are able to protect themselves against oxidative stress by via catalase activity.

Fish oil given by gavage increases lymphocyte proliferation and production of hydrogen peroxide by rat macrophages.

1. The effect of fish oil (FO) administration by gavage (0.4% body weight) on macrophage and lymphocyte function was investigated in young male rats. The results were compared with those obtained by administration of soybean oil (SB) and cocoa butter (CB). 2. Lymphocyte proliferation was markedly increased by FO administration compared with control and other oils. 3. Macrophage phagocytosis capacity was not affected by FO, but it was increased by CB and SB. 4. The oils did not affect the production of O2.- but increased the production of H2O2 in the presence of PMA. 5. The administration of the oils did not markedly affect the activity of antioxidant enzymes in macrophages, except for a decrease in superoxide dismutase activity by FO.

Percentage of phagocytosis, production of O2.-, H2O2 and NO, and antioxidant enzyme activities of rat neutrophils in culture.

Changes in the integrity, ultrastructure, phagocytosis capacity, and production of H2O2, O2.- and NO2- were evaluated in cultured neutrophils. The activities of the antioxidant enzymes (catalase-CAT, superoxide dismutase-SOD and glutathione-dependent peroxidase-GSH-Px) were measured under similar conditions. The integrity of the cells remained unchanged up to 18 h. After 24 h, the number of viable cells in culture dropped by 16 per cent. The percentage of viable cells in culture was of 72 per cent even after 72 h. An ultrastructural analysis of the cells was carried out after 3, 6, 12, 24, 48, and 72 h in culture. Neutrophils started developing morphologic changes after 24 h: decreased cell volume, abundant vacuoles (mainly around the nucleus), and also the presence of autophagic vacuoles. This period was then chosen for the study of neutrophil function and antioxidant enzyme activities. Neutrophils cultured for 24 h presented reduced phagocytosis capacity. The rates of production of H2O2 and O2.- remained unchanged after 24 h in culture. Concomitantly, these cells were also able to produce NO in significant amounts. The production of O2.- in response to PMA stimulus was lowered in 24-h cultured cells. Possibly, the production of oxygen and nitrogen reactive species accomplished with a decrease in the activities of CAT and GSH-Px play a key role for the process of apoptosis which takes place in neutrophils under these conditions.

Glutamine utilization by rat neutrophils: presence of phosphate-dependent glutaminase.

The capacity of rat neutrophils to utilize glutamine was investigated by 1) determination of oxygen consumption in the presence of glucose or glutamine, 2) measurement of maximal activity of phosphate-dependent glutaminase, 3) Northern blot, Western blot, and immunocytochemical detection of glutaminase, and 4) measurement of glutamine utilization and also production of ammonia, glutamate, aspartate, alanine, and lactate and decarboxylation of [U-14C]glutamine in cells incubated for 1 h. The rate of respiration by isolated neutrophils in the absence of added substrate was 5.0 nmol x min(-1) x 10(7) cells(-1). Maximal activity of phosphate-dependent glutaminase was 56 nmol x min(-1) x mg protein(-1) in freshly obtained neutrophils; the Michaelis-Menten constant was 3.5 mM for glutamine. This enzyme activity was inhibited by 2 mM glutamate, 2 mM oxoglutarate, and 2 mM NH4Cl. The presence of glutaminase protein (65 kDa) was confirmed by Western blot and immunocytochemical detection and the presence of the mRNA (6.0 kb) by Northern blot analysis. Glutamine was utilized by neutrophils incubated for 1 h at a rate of 12.8 nmol x min(-1) x mg protein(-1) when the amino acid was added to the medium at 2 mM, which is three to four times higher than the physiological concentration. In the presence of 0.5 mM glutamine, the amino acid was utilized at a rate of 2.9 nmol x min(-1) x mg protein(-1). The addition of 0.5 mM glutamate to the incubation medium caused a marked reduction (by 70%) in glutamine utilization by neutrophils. Glucose was utilized at 7.7 nmol x min(-1) x mg protein(-1) when cells were incubated in 5 mM glucose. The conversion of [U-14C]glutamine to 14CO2 was very low: <1% was totally oxidized. The formation of ammonia was approximately 27% of glutamine utilization, and the conversion of glutamine to glutamate, aspartate, alanine, and lactate accounted for approximately 84.6% of the total amino acid utilized by neutrophils. In this study, evidence is presented that, in addition to lymphocytes and macrophages, neutrophils also utilize glutamine.

Peroxidase activity may play a role in the cytotoxic effect of indole acetic acid.

Peroxidase activity in neutrophils is higher than in thioglycollate macrophages, while in lymphocytes this enzyme activity is very low. Indole-3-acetic acid is oxidized by peroxidase and the role of this enzyme in the cytotoxic effect of the compound was evaluated by measuring oxygen consumption, light emission and cell death in neutrophils, macrophages and lymphocytes. The increase in light emission, oxygen consumption and rate of cell death in cells cultured in the presence of indole-3-acetic acid presented a direct correlation with the peroxidase activity of the cells as follows: neutrophils > thioglycollate macrophages > resident macrophages > lymphocytes. Indeed, in lymphocytes that possess very low peroxidase activity, indole-3-acetic acid did not result in an increase in light emission or oxygen consumption and it was not cytotoxic.

Chemiexcitation in the peroxidative metabolism of N-methylcarbazole: mechanistic implications.

The peroxidative metabolism of N-methylcarbazole emits light independently of the presence of oxygen. It is likely that two chemiexcited transients are formed by electron transfer to the activated peroxidase, the cation radical by one electron transfer and a cation biradical by two electron transfer consistent with the failure to observe horseradish peroxidase-II in the steady state of the reaction. In the spectral range investigated (390-700 nm) the observed emission (570-700 nm) is ascribed to the biradical, as the latter is equivalent to an excited state of the postulated iminium cation. While lipoxygenase has no effect upon N-methylcarbazole, it markedly enhances the emission if peroxidase is present. This effect requires oxygen and is ascribed to an excited product formed by lipoxygenase acting upon an intermediate hydroperoxide of the aerobic process promoted by peroxidase. Our results are of importance on two counts. First they extend to N-methylcarbazole the formation of excited species in the peroxidative metabolism of important xenobiotics. Second, the mechanistic information they provide supports the scheme of metabolism postulated by Kedderis et al. (1986, J. Biol. Chem. 261, 15910-15914).

Horseradish peroxidase-catalyzed aerobic oxidation of indole-3-acetic acid. II. Oxygen uptake and chemiexcitation.

Light emission from the horseradish peroxidase-catalyzed aerobic or anaerobic oxidation of indole-3-acetic acid has been investigated under opposite extreme conditions of enzyme/substrate ratio. The O2-dependent chemiluminescent processes represent a minor part of the total oxygen consumption. Superoxide is involved in chemiexcitation as is evident from the observed inhibitory effect of superoxide dismutase. At high enzyme/substrate ratio, only a part of the emission is dependent on superoxide ion; at low ratio the dependence is extensive. At high ratio, some of the emission is independent of superoxide and O2. The identical quenching effects of D- and L-tryptophan are consistent with the formation of the quenching species only in bulk solution. The similarity of the emission spectra under extreme conditions indicates that the same main emitters are formed. This is also supported by the effect of quenchers. Possibly some of the emitters originate in the oxidative cleavage of the 2,3-double bond of the indole ring.

Horseradish peroxidase-catalyzed aerobic oxidation and peroxidation of indole-3-acetic acid. I. Optical spectra.

A study of the indole-3-acetate reaction with horse-radish peroxidase, in the absence or presence of hydrogen peroxide, has been performed, employing rapid scan and conventional spectrophotometry. We present here the first clear spectral evidence, obtained on the millisecond time scale, indicating that at pH 5.0 and for high [enzyme/substrate] ratios peroxidase compound III is formed. Most, if not all, of the compound III is formed by oxygenation of the ferrous peroxidase. There is an inhibitory effect of superoxide dismutase and histidine on compound III formation which indicates the involvement of the active oxygen species superoxide and singlet oxygen. It is concluded that the oxidation of indole-3-acetate by horseradish peroxidase at pH 5.0 proceeds through compound III formation to the catalytically inactive forms P-670 and P-630. A reaction path in which the enzyme is directly reduced by indole-3-acetate might be involved as an initiation step. Rapid scan spectral data, which indicate differences in the formation and decay of enzyme intermediate compounds at pH 7.0, in comparison with those observed at pH 5.0, are also presented. At pH 7.0 compound II is a key intermediate in oxidation--peroxidation of substrate. Mechanisms of reactions consistent with the experimental data are proposed and discussed.

Parasitoses intestinais em menores hospitalizados, filhos de previdenciarios. / Intestinal parasitoses in children hospitalized

Estudou-se a frequencia de enteropatias em 7.363 criancas, filhos de previdenciarios e hospitalizados no IMIP. O percentual de positividade foi de 48,06%, examinando-se uma amostra de fezes de cada paciente pelo metodo de Hoffman, Pons & Janer.Poliparasitismo foi observado em 21,89% da casuistica. Ascaridiase, tricuriase e giardiase foram as parasitoses mais comuns