146 resultados para Levels of lysine


Relevância:

100.00% 100.00%

Publicador:

Resumo:

The present experiment was aimed to study the effects of an isocaloric substitution of fat by carbohydrate calories while maintaining the same CP content - on some endocrine parameters and key metabolites of the lipid (L), protein (CP) and carbohydrate (CHO) metabolism and muscle cell membrane integrity of broiler chickens. Ninety male broiler chicks (Cobb) were obtained at 1-day old and raised in an environmentally controlled room. Food and water was provided ad libitum. At day 7, the chicks were provided with the experimental diets: Control diet (CON: 20% CP; 9.1% L; 39.6% CHO), Low lipid diet (LowL: 22% CP; 3.36% L; 59.7% CHO), and low carbohydrate diet (LowCHO: 22% CP; 8.09% L; 46.7% CHO). T e chickens fed the CON manifested the best growth rate feed conversion compared to both other groups. The CO chickens showed the highest plasma T-3 Concentrations at 14 days of age as compared to both LowL and LowCHO chickens. At 35 days of age however, LowL chickens were characterized by the highest plasma T-3 levels. Overall, CON birds had the highest plasma T-4 levels (P < 0.0001) compared to LowL and LowCHO chickens. Plasma corticosterone levels were not affected by diet composition. Glucose levels increased towards the end of the experimental period, but there was no overall effect of diet composition on plasma glucose levels. Chickens fed the CON diet were consistently characterized by the highest plasma uric acid levels compared to LowL and LowCHO chickens. Irrespectively of diet, plasma triglyceride levels were high at 14 days of age, then decreased and finally increased again during the last week. This latter increase was most pronounced for the CON chickens and is congruous with their high fat deposition. At 28 days of age, a significant effect of diet was observed, as CON birds had lower plasma free fatty acid (FFA) levels compared to LowL but not to LowCHO chickens. However there was no overall effect of diet composition on plasma FFA levels. Creatine kinase (CK) activities increased significantly with age and were consistently higher in CON chickens. In conclusion, fast growth in broiler chickens is positively correlated with catabolism of protein from dietary or endogenous origin and (muscle) cell membrane disruption as reflected in high plasma uric acid levels and CK activity, respectively. The currently investigated substitution of fat by CHO had no marked effects on endocrine functioning and intermediary metabolism, but this does not exclude that larger substitutions between both nutrients can have an effect.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Yields and starch pasting characteristics obtained from wet milling of maize samples with low and high levels of defect grains were compared to those from sound samples. Defect grain groups ere established taking into account the defect degree. Thus the first group consisted of fermented, molded, heated and sprouted grains and the second of insect damaged. hollow, fermented (up to 1/4) grains and those injured by other causes. The grain groups, if present at low levels in the samples, 10% for first group and 17% for second group did not affect the chemical composition of starch and its pasting properties. obtained by the rapid visco analyser. Samples with high levels of grain groups (up to 100%). affected wet milling yields and starch viscosity. Samples with 100% of grains in the first group decreased starch, germ yield and peak viscosity and increased gluten yield. Samples with 100% of grains in the second group decreased germ and fiber yield but increased starch yield. (C) 2002 Elsevier B.V. Ltd. All rights reserved.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

INTRODUCTION: Visual analysis is widely used to interpret regional cerebral blood flow (rCBF) SPECT images in clinical practice despite its limitations. Automated methods are employed to investigate between-group rCBF differences in research Studies but have rarely been explored in individual analyses.OBJECTIVES: To compare visual inspection by nuclear physicians with the automated statistical parametric mapping program using a SPECT dataset of patients with neurological disorders and normal control images.METHODS: Using statistical parametric mapping, 14 SPECT images from patients with various neurological disorders were compared individually with a databank of 32 normal images using a statistical threshold of p<0.05 (corrected for multiple comparisons at the level of individual voxels or clusters). Statistical parametric mapping results were compared with Visual analyses by a nuclear physician highly experienced in neurology (A) as well as a nuclear physician with a general background of experience (B) who independently classified images as normal or altered, and determined the location of changes and the severity.RESULTS: of the 32 images of the normal databank, 4 generated maps showing rCBF abnormalities (p<0.05, corrected). Among the 14 images from patients with neurological disorders, 13 showed rCBF alterations. Statistical parametric mapping and physician A completely agreed on 84.37% and 64.28% of cases from the normal databank and neurological disorders, respectively. The agreement between statistical parametric mapping and ratings of physician B were lower (71.18% and 35.71%, respectively).CONCLUSION: Statistical parametric mapping replicated the findings described by the more experienced nuclear physician. This finding suggests that automated methods for individually analyzing rCBF SPECT images may be a valuable resource to complement visual inspection in clinical practice.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Throughout the world, biomonitoring has become the standard for assessing exposure of individuals to toxic elements as well as for responding to serious environmental public health problems. However, extensive biomonitoring surveys require rapid and simple analytical methods. Thus, a simple and high-throughput method is proposed for the determination of arsenic (As), cadmium (Cd), copper (Cu), manganese (Mn), nickel (Ni), lead (Pb), and selenium (Se) in blood samples by using inductively coupled plasma-mass spectrometry (ICP-MS). Prior to analysis, 200 l of blood samples was mixed with 500 l of 10% v/v tetramethylammonium hydroxide (TMAH) solution, incubated for 10 min, and subsequently diluted to 10 ml with a solution containing 0.05% w/v ethylenediamine tetraacetic acid (EDTA) + 0.005% v/v Triton X-100. After that, samples were directly analyzed by ICP-MS (ELAN DRC II). Rhodium was selected as an internal standard with matrix-matching calibration. Method detection limits were 0.08, 0.04, 0.5, 0.09, 0.12, 0.04, and 0.1 g//L for As, Cd, Cu, Mn, Ni, Pb, and Se, respectively. Validation data are provided based on the analysis of blood samples from the trace elements inter-\comparison program operated by the Institut National de Sante Publique du Quebec, Canada. Additional validation was provided by the analysis of human blood samples by the proposed method and by using electrothermal atomic absorption spectrometry (ETAAS). The method was subsequently applied for the estimation of background metal blood values in the Brazilian population. In general, the mean concentrations of As, Cd, Cu, Mn, Ni, Pb, and Se in blood were 1.1, 0.4, 890, 9.6, 2.1, 65.4, and 89.3 g/L, respectively, and are in agreement with other global populations. Influences of age, gender, smoking habits, alcohol consumption, and geographical variation on the values were also considered. Smoking habits influenced the levels of Cd in blood. The levels of Cu, Mn, and Pb were significantly correlated with gender, whereas Cu and Pb were significantly correlated with age. There were also interesting differences in Mn and Se levels in the population living in the north of Brazil compared to the south.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Sleep bruxism (SB) is characterized by repetitive and coordinated mandible movements and non-functional teeth contacts during sleep time. Although the etiology of SB is controversial, the literature converges on its multifactorial origin. Occlusal factors, smoking, alcoholism, drug usage, stress, and anxiety have been described as SB trigger factors. Recent studies on this topic discussed the role of neurotransmitters on the development of SB.Thus, the purpose of this study was to detect and quantify the urinary levels of catecholamines, specifically of adrenaline, noradrenaline and dopamine, in subjects with SB and in control individuals.Urine from individuals with SB (n = 20) and without SB (n = 20) was subjected to liquid chromatography. The catecholamine data were compared by Mann-Whitney's test (p a parts per thousand currency sign 0.05).Our analysis showed higher levels of catecholamines in subjects with SB (adrenaline = 111.4 A mu g/24 h; noradrenaline = 261,5 A mu g/24 h; dopamine = 479.5 A mu g/24 h) than in control subjects (adrenaline = 35,0 A mu g/24 h; noradrenaline = 148,7 A mu g/24 h; dopamine = 201,7 A mu g/24 h). Statistical differences were found for the three catecholamines tested.It was concluded that individuals with SB have higher levels of urinary catecholamines.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This study evaluated the effect of different concentrations of selenium (Se) supplementation on cattle anti-rabies humoral immune response, serum Se concentrations and cortisol levels. Sixty uncastrated male Nelore calves from 10 to 12 months grazing on Brachiaria decumbens forage were studied. The animals were assigned to one of four groups (n = 15 each), which received non-supplemented diets (Gc) or supplemented with daily and individual Selenium ( Se) concentrations of 3.6 mg (G(3.6)), 5.4 mg (G(5.4)) or 6.4 mg (G(6.4)). The calves were immunized on day 0 with one dose of commercial liquid inactivated rabies vaccination. on days 15, 30, 60, 90 and 120, the cattle underwent the same stressing procedures used for vaccination in the corral. Cattle blood samples were collected after vaccination and stressing procedures to determine serum Se levels, rabies antibody titers and serum cortisol. Se levels were also determined in forage samples collected from the paddocks in which the cattle were held. Se concentration in B. decumbens was 0.04 mg of Se/kg dry matter. Baseline Se levels obtained on day 0 were higher in Gc than in G(5.4) and G(6.4) (P = 0.005). Serum Se levels decreased in Gc throughout the experiment (P < 0.004), increased in G(3.6) (P < 0.000) and G(5.4) (P < 0.000) and were kept high from day 60 on in group G(6.4) (P < 0.002). Rabies antibody titers did not differ among control and supplemented groups. However, 120 days after vaccination rabies antibody titers were kept above protective levels (>= 0.5 UI/mL) only in group G(3.6) (P < 0.00002), whereas they dropped in the other groups (P < 0.05). Serum cortisol levels did not differ among the experimental groups (P = 0.79), reached peak levels on day 90 and returned close to baseline levels on day 120. Se and cortisol levels were not markedly correlated. Serum cortisol and rabies antibody titers were correlated only in group G(6.4), on day 60 (R = 0.513; P = 0.05) and 120 (R = 0.644; P = 0.009). Serum Se and rabies antibody titers were correlated only in group G(6.4), on day 60 (R = -0.580; P = 0.023). In conclusion: a) the profile of Se variation is different among groups receiving different concentrations of this element; b) the supplementation dosage of 3.6 mg Se/animal/day is efficient to treat/prevent marginal Se deficiency; c) individual supplementation with daily concentrations of 3.6 mg Se enhances the maintenance of rabies antibody titers in cattle; d) individual supplementation with daily concentrations of 3.6; 5.4 and 6.4 mg Se are ineffective in reducing serum cortisol; e) repeated cattle handling in corrals stress animals that adapt to these procedures, although serum cortisol does not return to baseline levels by 120 days; and f) the stress generated by repeated management in cattle in the corral does not diminish antibody titers after vaccination against rabies.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The objective of the present study was to evaluate the nutrient intake, blood parameters, follicular diameter and performance of pre-puberty crossbred heifers fed isoproteic diets (14.1%CP) containing 0.0; 0.44; 0.88 and 1.32% urea on the total dry matter (DM) of the diet, with a 77:23 roughage:concentrate ratio. Twenty-four 18- month old heifers (Holstein x Zebu), 277.9 kg mean live weight (LW) were used, distributed in four treatments and six replications in a randomized complete design. The following were evaluated: dry matter intake (DM), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), ether extract (EE), hemicellulose (HEM), plasmatic ureic nitrogen (PUN), plasmatic glucose, plasmatic total cholesterol, follicular diameter and daily weight gain (DWG). No influence of the urea levels in the diet was observed on NDF and HEM intake. A maximum intake was obtained of DM (8.75 kg day(-1)), CP (0.88 kg day(-1)), ADF (2.5 kg day(-1)) and EE (0.17 kg day(-1)) respectively for the levels 0.7, 0.8, 0.7 and 0.7% urea in total DM. The 0.6%; 0.77% and 0.6% urea levels in diet were the critical points for obtaining maximum response for the PUN (10.96 mg dL(-1)) and plasmatic glucose (84.97 mg dL(-1)) concentrations and, for follicular diameter (11.08 mm) on the 40(th); 24(th) and 31(st) day, respectively. The plasmatic total cholesterol concentration and DWG were not influenced by the urea added to the diet, with averages of 119.39 mg dL(-1) and 1.66 kg day(-1), respectively. It was concluded that urea can be added up to 1.32% on the total DM of the diet for pre-puberty crossbred heifers.