909 resultados para Omission of micronutrients
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Iron, copper, and zinc are essential for all living organisms. Moreover, the homeostasis of these metals is vital to microorganisms during pathogenic interactions with a host. Most pathogens have developed specific mechanisms for the uptake of micronutrients from their hosts in order to counteract the low availability of essential ions in infected tissues. We report here an analysis of genes potentially involved in iron, copper, and zinc uptake and homeostasis in the fungal pathogens Paracoccidioides brasiliensis, Cryptococcus neoformans var. grubii, and Cryptococcus gattii. Although prior studies have identified certain aspects of metal regulation in Cryptococcus species, little is known regarding the regulation of these elements in P. brasiliensis. We also present amino acid sequences analyses of deduced proteins in order to examine possible conserved domains. The genomic data reveals, for the first time, genes associated to iron, copper, and zinc assimilation and homeostasis in P. brasiliensis. Furthermore, analyses of the three fungal species identified homologs to genes associated with high-affinity uptake systems, vacuolar and mitochondrial iron storage, copper uptake and reduction, and zinc assimilation. However, homologs to genes involved in siderophore production were only found in P. brasiliensis. Interestingly, in silico analysis of the genomes of P. brasiliensis Pb01, Pb03, and Pb18 revealed significant differences in the presence and/or number of genes involved in metal homeostasis, such as in genes related to iron reduction and oxidation. The broad analyses of the genomes of P. brasiliensis, C. neoformans var. grubii, and C. gattii for genes involved in metal homeostasis provide important groundwork for numerous interesting future areas of investigation that are required in order to validate and explore the function of the identified genes and gene pathways.
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Nutritional deficiencies, especially micronutrient deficiencies, can occur in obese individuals. Surgical treatment may aggravate or cause these deficiencies, depending on the type of procedure, food intake and the use of multivitamins, minerals or other supplements. The objective of the study was to evaluate the nutrient intake of women who had undergone Roux-en-Y gastric bypass (RYGB) surgery. A cross-sectional, controlled study was conducted among 44 women after RYGB (operated-group, OG; mean years post-operation = 3.4) and a control group of 38 healthy women (non-operated group, NOG) matched by age and economic condition. The women reported their dietary intake using a 4-day record. The Dietary Reference Intakes was used as a reference. The macronutrient contributions to dietary energy intake presented an acceptable distribution for proteins and carbohydrates. Lipid intake was high among women in the OG and the NOG (43.2 and 55.3 %, respectively). In the evaluation of micronutrients, a statistically significant difference was observed between the groups for iron, zinc and vitamins B1 and B12. Both groups were at high risk for inadequate calcium intake, and the OG was at risk for inadequate zinc, iron and vitamin B1 intake. The nutrient intake of women who had undergone RYGB is very similar to that of non-operated women, with the exception of a reduced intake of iron, zinc and vitamins B1 and B12, which may be due to the difficulty of consuming meat and a balanced diet. The findings of this study emphasize the importance of appropriate nutritional intervention and the regular use of multivitamin and mineral supplements for these patients.
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Objective This study analyzed the internal functioning, organization and political participation of the local food and nutrition security council and possible implications of their participation on the creation of a municipal food and nutrition security policy in the city of Sao Paulo. Methods This qualitative study was done in three stages: document analysis; observation of meetings and semi-structured interviews with board members considered key informants. The axis of analysis was the political participation of the council, considering its internal aspects, like board members, operating dynamics of political participation of its members and the relationship between these topics and the council's actions for the definition and creation of a food and nutrition security policy. Results The intellectual profile of the board members does not represent the majority of the population, thereby facilitating the omission of actual issues in council discussions. Its strict internal dynamics and the asymmetry of its members generally prevent the active participation of board members and, specifically, discussions about a food and nutrition security policy. The so-called "militant members" have a differentiated, more aggressive participation, with greater mastery of the subject and its topics. Conclusion The board member profiles, internal organization of the council, complexity of the subject and its low insertion in the society distance the council from social needs and lead them to act incipiently with regard to the municipal policies of food and nutrition security.
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Economic theory distinguishes two concepts of utility: decision utility, objectively quantifiable by choices, and experienced utility, referring to the satisfaction by an obtainment. To date, experienced utility is typically measured with subjective ratings. This study intended to quantify experienced utility by global levels of neuronal activity. Neuronal activity was measured by means of electroencephalographic (EEG) responses to gain and omission of graded monetary rewards at the level of the EEG topography in human subjects. A novel analysis approach allowed approximating psychophysiological value functions for the experienced utility of monetary rewards. In addition, we identified the time windows of the event-related potentials (ERP) and the respective intracortical sources, in which variations in neuronal activity were significantly related to the value or valence of outcomes. Results indicate that value functions of experienced utility and regret disproportionally increase with monetary value, and thus contradict the compressing value functions of decision utility. The temporal pattern of outcome evaluation suggests an initial (∼250 ms) coarse evaluation regarding the valence, concurrent with a finer-grained evaluation of the value of gained rewards, whereas the evaluation of the value of omitted rewards emerges later. We hypothesize that this temporal double dissociation is explained by reward prediction errors. Finally, a late, yet unreported, reward-sensitive ERP topography (∼500 ms) was identified. The sources of these topographical covariations are estimated in the ventromedial prefrontal cortex, the medial frontal gyrus, the anterior and posterior cingulate cortex and the hippocampus/amygdala. The results provide important new evidence regarding “how,” “when,” and “where” the brain evaluates outcomes with different hedonic impact.
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Neonates are particularly susceptible to malnutrition due to their limited reserves of micronutrients and their rapid growth. In the present study, we examined the effect of vitamin C deficiency on markers of oxidative stress in plasma, liver and brain of weanling guinea pigs. Vitamin C deficiency caused rapid and significant depletion of ascorbate (P < 0.001), tocopherols (P < 0.001) and glutathione (P < 0.001), and a decrease in superoxide dismutase activity (P = 0.005) in the liver, while protein oxidation was significantly increased (P = 0.011). No changes in lipid oxidation or oxidatively damaged DNA were observed in this tissue. In the brain, the pattern was markedly different. Of the measured antioxidants, only ascorbate was significantly depleted (P < 0.001), but in contrast to the liver, ascorbate oxidation (P = 0.034), lipid oxidation (P < 0.001), DNA oxidation (P = 0.13) and DNA incision repair (P = 0.014) were all increased, while protein oxidation decreased (P = 0.003). The results show that the selective preservation of brain ascorbate and induction of DNA repair in vitamin C-deficient weanling guinea pigs is not sufficient to prevent oxidative damage. Vitamin C deficiency may therefore be particularly adverse during the neonatal period.
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The molecular interactions between the host molecule, perthiolated beta-cyclodextrin (CD), and the guest molecules, adamantaneacetic acid (AD) and ferroceneacetic acid (FC), have been inestigated theoretically in both the gas and aqueous phases. The major computations have been carried out at the theoretical levels, RHF/6-31G and B3LYP/6- 31G. MP2 electronic energies were also computed based at the geometries optimized by both the RHF and B3LYP methods in the gas phase to establish a better estimate of the correlation effect. The solvent phase computations were completed at the RHF/6-31G and B3LYP/6-31G levels using the PCM model. The most stable structures optimized in gas phase by both the RHF and B3LYP methods were used for the computations in solution. A method to systematically manipulate the relative position and orientation between the interacting molecules is proposed. In the gas phase, six trials with different host-guest relative positions and orientations were completed successfully with the B3LYP method for both the CD-AD and CD-FC complexes. Only four trials were completed with RHF method. In the gas phase, the best results from the RHF method gives for the association Gibbs free energy (ΔG°) values equal to -32.21kj/mol for CD-AD and -25.73kj/mol for CD-FC. And the best results from the B3LYP method have ΔG° equal to -47.57kj/mol for CD-AD and -41.09kj/mol for CD-FC. The MP2 correction significantly lowers ΔG° based on the geometries from both methods. For the RHF structure, the MP2 computations lowered ΔG° to -60.64kj/mol for CD-AD and -54.10 for CD-FC. For the structure from the B3LYP method, it was reduced to -59.87 kj/mol for CD-AD and -54.84 kj/mol for CDFC. The RHF solvent phase calculations yielded following results: ΔG°(aq) equals 107.2kj/mol for CD-AD and 111.4kj/mol for CD-FC. Compared with the results from the RHF method, the B3LYP method provided clearly better solvent phase results with ΔG° (aq) equal to 38.64kj/mol for CD-AD and 39.61kj/mol for CD-FC. These results qualitatively explain the experimental observations. However quantitatively they are in poor agreement with the experimental values available in the literature and those recently published by Liu et al. And the reason is believed to be omission of hydrophobic contribution to the association. Determining the global geometrical minima for these very large systems was very difficult and computationally time consuming, but after a very thorough search, these were identified. A relevant result of this search is that when the complexes, CD-AD and CD-FC, are formed, the AD and FC molecules are only partially embedded inside the CD cavity. The totally embedded complexes were found to have significantly higher energies. The semiempirical method, ZINDO, was employed to investigate the effect of complexation on the first electronic excitation of CD anchored to a metal nano-particle. The computational results revealed that after complexation to FC, the transition intensity declines to about 25% of the original value, and after complexation with AD, the intensity drops almost 50%. The tighter binding and transition intensity of CD-AD qualitatively agrees with the experimental result that the addition of AD to a solution of CD and FC restores the fluorescence of CD that was quenched by the addition of FC. A method to evaluate the “hydrophobic force” effect is proposed for future work.
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Displacements of the Earth’s surface caused by tidal and non-tidal loading forces are relevant in high-precision space geodesy. Some of the corrections are recommended by the international scientific community to be applied at the observation level, e.g., ocean tidal loading (OTL) and atmospheric tidal loading (ATL). Non-tidal displacement corrections are in general recommended not to be applied in the products of the International Earth Rotation and Reference Systems Service, in particular atmospheric non-tidal loading (ANTL), oceanic and hydrological non-tidal corrections. We assess and compare the impact of OTL, ATL and ANTL on SLR-derived parameters by reprocessing 12 years of SLR data considering and ignoring individual corrections. We show that loading displacements have an influence not only on station long-term stability, but also on geocenter coordinates, Earth Rotation Parameters, and satellite orbits. Applying the loading corrections reduces the amplitudes of annual signals in the time series of geocenter and station coordinates. The general improvement of the SLR station 3D coordinate repeatability when applying OTL, ATL and ANTL corrections are 19.5 %, 0.2 % and 3.3 % respectively, w.r.t. the solutions without loading corrections. ANTL corrections play a crucial role in the combination of optical (SLR) and microwave (GNSS, VLBI, DORIS) space geodetic observation techniques, because of the so-called Blue-Sky effect: SLR measurements can be carried out only under cloudless sky conditions—typically during high air pressure conditions, when the Earth’s crust is deformed, whereas microwave observations are weather-independent. Thus, applying the loading corrections at the observation level improves SLR-derived products as well as the consistency with microwave-based results. We assess the Blue-Sky effect on SLR stations and the consistency improvement between GNSS and SLR solutions when ANTL corrections are included. The omission of ANTL corrections may lead to inconsistencies between SLR and GNSS solutions of up to 2.5 mm for inland stations. As a result, the estimated GNSS–SLR coordinate differences correspond better to the local ties at the co-located stations when applying ANTL corrections.
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BACKGROUND Fever and neutropenia (FN) often complicate anticancer treatment and can be caused by potentially fatal infections. Knowledge of pathogen distribution is paramount for optimal patient management. METHODS Microbiologically defined infections (MDI) in pediatric cancer patients presenting with FN by nonmyeloablative chemotherapy enrolled in a prospective multi-center study were analyzed. Effectiveness of empiric antibiotic therapy in FN episodes with bacteremia was assessed taking into consideration recently published treatment guidelines for pediatric patients with FN. RESULTS MDI were identified in a minority (22%) of pediatric cancer patients with FN. In patients with, compared to without MDI, fever (median, 5 [IQR 3-8] vs. 2 [IQR1-3] days, p < 0.001) and hospitalization (10 [6-14] vs. 5 [3-8] days, p < 0.001) lasted longer, transfer to the intensive care unit was more likely (13 of 95 [14%] vs. 7 of 346 [2.0%], p < 0.001), and antibiotics were given longer (10 [7-14] vs. 5 [4-7], p < 0.001). Empiric antibiotic therapy in FN episodes with bacteremia was highly effective if not only intrinsic and reported antimicrobial susceptibilities were considered but the purposeful omission of coverage for coagulase negative staphylococci and enterococci was also taken into account (81% [95%CI 68 - 90] vs. 96.6% [95%CI 87 - 99.4], p = 0.004) CONCLUSIONS: MDI were identified in a minority of FN episodes but they significantly affected management and the clinical course of pediatric cancer patients. Compliance with published guidelines was associated with effectiveness of empiric antibiotic therapy in FN episodes with bacteremia.
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OBJECTIVE Anorexia nervosa is associated with several serious medical complications related to malnutrition, severe weight loss, and low levels of micronutrients. The refeeding phase of these high-risk patients bears a further threat to health and potentially fatal complications. The objective of this study was to examine complications due to refeeding of patients with anorexia nervosa, as well as their mortality rate after the implementation of guidelines from the European Society of Clinical Nutrition and Metabolism. METHODS We analyzed retrospective, observational data of a consecutive, unselected anorexia nervosa cohort during a 5-y period. The sample consisted of 65 inpatients, 14 were admitted more than once within the study period, resulting in 86 analyzed cases. RESULTS Minor complications associated with refeeding during the first 10 d (replenishing phase) were recorded in nine cases (10.5%), four with transient pretibial edemas and three with organ dysfunction. In two cases, a severe hypokalemia occurred. During the observational phase of 30 d, 16 minor complications occurred in 14 cases (16.3%). Six infectious and 10 non-infectious complications occurred. None of the patients with anorexia nervosa died within a follow-up period of 3 mo. CONCLUSIONS Our data demonstrate that the seriousness and rate of complications during the replenishment phase in this high-risk population can be kept to a minimum. The findings indicate that evidence-based refeeding regimens, such as our guidelines are able to reduce complications and prevent mortality. Despite anorexia nervosa, our sample were affected by serious comorbidities, no case met the full diagnostic criteria for refeeding syndrome.
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The phloem mobility of heavy metals is relevant to the redistribution of micronutrients and pollutants and, ultimately, to the quality of harvested plant parts. The relative mobility in wheat may vary considerably between different cations. In the study reported here, radio-labeled nickel (Ni), cobalt (Co), manganese (Mn), zinc (Zn) and cadmium (Cd) were introduced into either intact young winter wheat (Triticum aestivum L. cv. Arina) via a leaf flap, or detached maturing shoots via the cut stem. Elements fed into the lamina of the second leaf of 21-day-old plants were translocated to the younger (expanding) leaves and to the roots but not or only in trace amounts to the first (already fully expanded) leaf. The 63Ni and 65Zn were exported more rapidly compared with the other heavy metals. Most of 54Mn was retained in the originally labeled leaf. The peduncle of some maturing shoots was steam-girdled below the ear to distinguish between xylem and phloem transport. This phloem interruption reduced the content of 63Ni in the ear to about 25%. Intermediate effects were observed for 65Zn, 57Co, and 109Cd. Total 54Mn accumulation in the ear was hardly affected by steam-girdling, indicating a transport of this element within the xylem to the ear. These results suggest that the relative phloem mobility of Ni and Zn in young wheat plants and in maturing wheat shoots is higher than the mobility of Co and Cd, whereas the mobility of Mn is very low.
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Cysteine synthesis from sulfide andO-acetyl-L-serine (OAS) is a reaction interconnecting sulfate, nitrogen, and carbon assimilation. UsingLemna minor, we analyzed the effects of omission of CO2 from the atmosphere and simultaneous application of alternative carbon sources on adenosine 5′-phosphosulfate reductase (APR) and nitrate reductase (NR), the key enzymes of sulfate and nitrate assimilation, respectively. Incubation in air without CO2 led to severe decrease in APR and NR activities and mRNA levels, but ribulose-1,5-bisphosphate carboxylase/oxygenase was not considerably affected. Simultaneous addition of sucrose (Suc) prevented the reduction in enzyme activities, but not in mRNA levels. OAS, a known regulator of sulfate assimilation, could also attenuate the effect of missing CO2 on APR, but did not affect NR. When the plants were subjected to normal air after a 24-h pretreatment in air without CO2, APR and NR activities and mRNA levels recovered within the next 24 h. The addition of Suc and glucose in air without CO2 also recovered both enzyme activities, with OAS again influenced only APR.35SO4 2− feeding showed that treatment in air without CO2 severely inhibited sulfate uptake and the flux through sulfate assimilation. After a resupply of normal air or the addition of Suc, incorporation of 35S into proteins and glutathione greatly increased. OAS treatment resulted in high labeling of cysteine; the incorporation of 35S in proteins and glutathione was much less increased compared with treatment with normal air or Suc. These results corroborate the tight interconnection of sulfate, nitrate, and carbon assimilation.
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Using Arabidopsis, we analyzed the effect of omission of a nitrogen source and of the addition of different nitrogen-containing compounds on the extractable activity and the enzyme and mRNA accumulation of adenosine 5′-phosphosulfate reductase (APR). During 72 h without a nitrogen source, the APR activity decreased to 70% and 50% of controls in leaves and roots, respectively, while cysteine (Cys) and glutathione contents were not affected. Northern and western analysis revealed that the decrease of APR activity was correlated with decreased mRNA and enzyme levels. The reduced APR activity in roots could be fully restored within 24 h by the addition of 4 mM each of NO3 −, NH4 +, or glutamine (Gln), or 1 mM O-acetylserine (OAS). 35SO4 2− feeding showed that after addition of NH4 +, Gln, or OAS to nitrogen-starved plants, incorporation of 35S into proteins significantly increased in roots; however, glutathione and Cys labeling was higher only with Gln and OAS or with OAS alone, respectively. OAS strongly increased mRNA levels of all three APR isoforms in roots and also those of sulfite reductase, Cys synthase, and serine acetyltransferase. Our data demonstrate that sulfate reduction is regulated by nitrogen nutrition at the transcriptional level and that OAS plays a major role in this regulation.
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Giardia duodenalis is considered the most common protozoan infecting humans worldwide. Molecular characterization of G. duodenalis isolates has revealed the existence of eight groups (assemblages A to H) which differ in their host distribution. A cross-sectional study was conducted in 639 children from La Habana between January and December 2013. Two assemblage-specific PCRs were carried out for the molecular characterization. The overall prevalence of Giardia infection was 11.9%. DNA from 63 of 76 (82.9%) samples was successfully amplified by PCR-tpi, while 58 from 76 (76.3%) were detected by PCRE1-HF. Similar results by both PCRs were obtained in 54 from 76 samples (71%). According to these analyses, assemblage B and mixed assemblages A + B account for most of the Giardia infections in the cohort of children tested. Our current study identified assemblage B as predominant genotype in children infected with Giardia. Univariate analysis indicated that omission of washing hands before eating and keeping dogs at home were significant risk factors for a Giardia infection. In the future, novel molecular tools for a better discrimination of assemblages at the subassemblages level are needed to verify possible correlations between Giardia genotypes and symptomatology of giardiasis.
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It is the aim of this paper to examine iron supplementation programs which receive funding from United States Agency for International Development (USAID) but approach combating iron deficiency anemia in two vastly different ways. A brief literature review and background information on iron deficiencies and the differences between supplementation programs and micronutrient fortification were reviewed. Two non-governmental organizations (NGO's) were examined for this paper: the Food and Nutrition Technical Assistance II (FANTA) and the MicroNutrient Initiative. The FANTA program included an educational component to their supplementation program while the MicroNutrient Initiative solely used supplementation of micronutrients to their population. Methods used were cost-benefit analysis and cost-effectiveness analysis to determine the overall effectiveness of each program in reducing iron deficiency anemia in each population, if the added costs of the incentives in the FANTA program changed the cost-effectiveness of the program compared to the MicroNutrient Initiative program and to determine which program imparted the greatest benefit to each population by reducing the disease burden in Disability Adjusted Life Years (DALY). Results showed that the unit cost of the FANTA program per person was higher than the MicroNutrient Initiative program due to the educational component. The FANTA program reduced iron deficiency anemia less overall but cost less for each percentage point of anemia decreased in their respective populations. The MicroNutrient Initiative program had a better benefit cost ratio for the populations it served. The MicroNutrient Initiative's large scale program imparted many advantages by reducing unit cost per person and decreasing iron deficiency anemia. The FANTA program was more effective at decreasing iron deficiency anemia with less money: $5,660 per 1% decrease in iron deficiency anemia versus $18,450 per 1% decrease in iron deficiency anemia for the MicroNutrient Initiative program. ^ In conclusion, economic analysis cannot measure all of the benefits associated with programs that contain an educational component or large scale supplementation. More information needs to be gathered by NGOs and reported to USAID, such as detailed prevalence rates of iron deficiency anemia among the populations served. Further research is needed to determine the effects an educational supplementation program has on compliance rates of participants and motivation to participate in supplementation programs whose aim is to decrease iron deficiency anemia in a targeted population.^