Use of Theoretical Women and Model-Based Compartmental Analysis to Evaluate the Impact of Vitamin A Intake with or without a Daily Vitamin A Supplement on Vitamin A Total Body Stores and Balance During Lactation.

BACKGROUND: Inadequate vitamin A (VA) intake is common among lactating women in many communities worldwide, but high-dose VA supplementation for postpartum women is not recommended by the World Health Organization as an effective intervention. OBJECTIVES: To simulate the impact of VA intake via diet and daily VA supplements on VA total body stores (TBS) and balance in theoretical lactating women with low/moderate TBS. METHODS: We studied 6 theoretical subjects with assigned values for TBS from 219-624 µmol. Using Simulation, Analysis, and Modeling software and a previously published compartmental model for whole-body VA metabolism, we simulated TBS over 6 mo of established lactation for each subject under 4 conditions: 1) prelactation VA intake was increased to maintain VA balance (LSS); 2) prelactation VA intake was maintained (NLSS); 3) VA intake was the same as 2) but a daily VA supplement (2.8 µmol/d) was added (NLSS+S); and 4) VA intake was as 1) and the daily VA supplement was included (LSS+S). RESULTS: To compensate for the loss of VA via milk while VA balance was maintained (LSS) over 6 mo of lactation, VA intake had to increase by 0.8-1.87 µmol/d (n = 6) compared with NLSS. Over 6 mo of NLSS treatment, VA balance was negative (geometric mean, -0.77 µmol/d) compared with LSS, whereas balance was positive under NLSS+S and LSS+S conditions (0.75 and 1.5 µmol/d, respectively). For LSS, the proportion of total VA disposal was 37% via breastmilk, 32% from VA stores, and 32% from nonstorage tissues. CONCLUSIONS: Adding a daily VA supplement (2.8 µmol/d) to the diet of lactating women with suboptimal VA intake may effectively counterbalance the negative VA balance resulting from the output of VA via breastmilk and thus benefit both mother and infant by maintaining or increasing VA stores and breastmilk VA concentration.

Direct Use of Plasma or Milk Vitamin A Specific Activity Data to Model Retinol Kinetics and Predict Vitamin A Stores in Theoretical Lactating Women.

BACKGROUND: Many applications of the Simulation, Analysis and Modeling software use data on the fraction of an orally administered tracer dose (FD) in plasma; thus, researchers must scale-up measured analyte concentration to the total plasma pool. For studies in lactating women, estimating breast milk pool size is challenging. OBJECTIVES: The objectives were to determine whether the standard vitamin A modeling approach using FD data could be modified to use vitamin A specific activity in milk (SAm) and/or plasma (SAp) for compartmental analysis of vitamin A kinetics and status in theoretical lactating women. METHODS: Using 12 previously studied theoretical subjects with a wide range of assigned values for vitamin A total body stores (TBS) and the coefficient ("FaS") needed to predict TBS using a retinol isotope dilution equation, we simulated data for SAp and SAm for 49 d after oral administration of labeled vitamin A. Then we modeled datasets for SAp and SAm, as well as only SAp or SAm, incorporating a linear scaling factor to automatically convert SA to FD and including several physiologically reasonable constraints as input data. As outcomes, we compared model-predicted TBS and FaS to assigned values. RESULTS: Scaling factors effectively adjusted SA data to adequately predict vitamin A mass in plasma and breast milk pools. Data for SAp and SAm provided model predictions of TBS that were comparable to assigned values (range: 85-107%); using only SAp, ratios ranged from 92% to 108% and for SAm from 85% to 108%. Parallel results were obtained for simulated FaS. CONCLUSIONS: Results show that SA data from plasma and/or milk can be used directly for modeling vitamin A during lactation in theoretical subjects, providing accurate estimates of TBS and FaS. Results suggest that, in free-living lactating women, researchers might measure only SAp or only SAm and adequately describe whole-body vitamin A metabolism and status.

Compartmental Modeling of Vitamin A Stable Isotope Data from Milk or Plasma Provides Comparable Predictions of Vitamin A Stores in Theoretical Lactating Women.

BACKGROUND: Previous compartmental models describing and quantifying whole-body vitamin A (VA) metabolism have been developed from plasma retinol kinetic data after human subjects ingest stable isotope-labeled VA. For humans, models based on data obtained from other sampling sites (e.g., excreta or milk) have not been proposed. OBJECTIVES: Our objective was to determine whether comparable model predictions of VA total body stores (TBS) in theoretical lactating women were obtained using tracer data from only retinol in plasma or VA in milk. METHODS: We used Simulation, Analysis and Modeling software to simulate values for TBS and the coefficients used in the retinol isotope dilution (RID) equation TBS = FaS/SAp (Fa, fraction of dose in stores; S, retinol specific activity (SA) in plasma/SA in stores; SAp, specific activity in plasma). We compared individual subject predictions of TBS and FaS based on modeling only plasma or only milk tracer data to previous results ("assigned values") for 12 theoretical lactating women when modeling was done based on tracer data for chylomicron retinyl esters, plasma retinol, and milk VA. RESULTS: For subjects with a wide range of TBS, model-predicted TBS based on only plasma data were comparable with assigned values (range: 94%-106%). Using only milk data, predictions ranged from 72% to 178%, but when VA intake was included in modeling, predictions were improved (97%-102%). Similar results were obtained for simulated FaS. CONCLUSIONS: If confirmed in free-living lactating women, results indicate that, similar to models based on serial plasma sampling, a model for whole-body VA kinetics, including predictions of TBS and FaS, can be identified based on tracer data for VA in milk when VA intake is included as a modeling constraint. Milk data have not been previously used for compartmental modeling of VA in humans.

Development of a Compartmental Model for Studying Vitamin A Kinetics and Status in Theoretical Lactating Women.

BACKGROUND: Low vitamin A status and suboptimal milk vitamin A concentrations are problems in many populations worldwide. However, limited research has been done on whole-body vitamin A kinetics in women of reproductive age, especially during lactation. OBJECTIVES: Goals were to develop compartmental models describing retinol kinetics in theoretical nonlactating (NL) and lactating (L) women and to determine whether the retinol isotope dilution (RID) method accurately predicted vitamin A total body stores (TBS) in the groups and individuals. METHODS: We adapted 12 previously-used theoretical females with assigned values for retinol kinetic parameters and TBS (225-1348 µmol); subjects were NL or L (nursing one 3- to 6-mo-old infant) during 49-d kinetic studies after isotope dosing. We used an established compartmental model, adding a compartment for chylomicrons and, for L, another for mammary gland milk with inputs from holo-retinol-binding protein and chylomicron retinyl esters and output to milk. Using compartmental analysis, we simulated tracer responses in compartments of interest and calculated TBS using the RID equation TBS =   FaS/SAp [Fa, fraction of dose in stores; S, retinol specific activity in plasma/specific activity in stores; SAp, specific activity of retinol in plasma]. RESULTS: Models for both groups were well identified. Simulated plasma tracer responses were similar for NL and L, with L always below NL; milk tracer paralleled plasma from 10 d postdosing. Geometric mean FaS ratios (L/NL) were ∼0.75 during days 2-30. Using appropriate group FaS, RID provided accurate TBS predictions for >80% of NL and L subjects after day 18 when CV% for FaS was ∼10%. CONCLUSIONS: These new physiologically-based models for vitamin A kinetics may be useful for future research in women of reproductive age. Results indicate that, in groups like these, RID to assess an individual's vitamin A status should be done at 21-28 d after isotope dosing.

Use of Compartmental Modeling and Datasets for Theoretical Lactating Women to Determine Conditions under Which Vitamin A-Specific Activity in Breast Milk Provides Accurate Estimates of Vitamin A Total Body Stores by Retinol Isotope Dilution.

BACKGROUND: Vitamin A concentrations in breast milk are related to maternal vitamin A intake and status. OBJECTIVES: Our objective was to identify conditions under which vitamin A specific activity in breast milk (SAm) could be used instead of retinol specific activity in plasma (SAp) to predict vitamin A total body stores (TBS) by retinol isotope dilution (RID). METHODS: We used 12 previously-studied theoretical lactating women with assigned values for TBS (219-1348 µmol) and retinol kinetic parameters; we assumed subjects ingested a dose of stable isotope-labeled vitamin A. We expanded a 9-compartment steady state tracer model to include a parallel model for tracee (unlabeled retinol) and then adapted that model so vitamin A intake entered the system in 3 meals each day. Using compartmental analysis, we first simulated SAm and SAp after an overnight fast (as in actual RID experiments) and then with vitamin A intake also restricted in sequential meals on the day before sampling for RID. RESULTS: After an overnight fast, SAm at day 21 postdosing was lower than SAp. However, if vitamin A intake was also restricted in 1, 2, or 3 meals before sampling, SAm/SAp (mean ± SD) was 0.92 ± 0.042,  0.96 ± 0.016,  or 0.99 ± 0.004,  respectively; results for days 14 and 28 were similar. When either SAp or SAm was used to predict TBS by RID on day 21 after 1-d restriction, predictions for all subjects were within 25% of assigned TBS. CONCLUSIONS: Results indicate that, for theoretical lactating women with a wide range of vitamin A status, SAm will accurately predict TBS by RID at 2-4 wk postdosing if vitamin A intake is restricted for 1 d before sampling. If confirmed in community settings, results suggest that vitamin A status in lactating women can be determined without collecting blood.

Does the Amount of Stable Isotope Dose Influence Retinol Kinetic Responses and Predictions of Vitamin A Total Body Stores by the Retinol Isotope Dilution Method in Theoretical Children and Adults?

BACKGROUND: To minimize both cost and perturbations to the vitamin A system, investigators limit the amount of stable isotope administered when estimating vitamin A total body stores (TBS) by retinol isotope dilution (RID). OBJECTIVES: We hypothesized that reasonable increases in the mass of stable isotope administered to theoretical subjects would have only transient impacts on vitamin A kinetics and minimal effects on RID-predicted TBS. METHODS: We adapted previously used theoretical subjects (3 children, 3 adults) with low, moderate, or high assigned TBS and applied compartmental analysis to solve a steady state model for tracer and tracee using assigned values for retinol kinetic parameters and plasma retinol. To follow retinol trafficking when increasing amounts of stable isotope were administered [1.39-7 (children) and 2.8-14 µmol retinol (adults)], we added assumptions to an established compartmental model so that plasma retinol homeostasis was maintained. Using model-simulated data, we plotted retinol kinetics versus time and applied the RID equation TBS = FaS/SAp [Fa, fraction of dose in stores; S, retinol specific activity (SA) in plasma/SA in stores; SAp, SA in plasma] to calculate vitamin A stores. RESULTS: The model predicted that increasing the stable isotope dose caused transient early increases in hepatocyte total retinol; increases in plasma tracer were accompanied by decreases in tracee to maintain plasma retinol homeostasis. Despite changes in kinetic responses, RID accurately predicted assigned TBS (98-105%) at all loads for all theoretical subjects from 1 to 28 d postdosing. CONCLUSIONS: Results indicate that, compared with doses of 1.4-3.5 µmol used in recent RID field studies, doubling the stable isotope dose should not affect the accuracy of TBS predictions, thus allowing for experiments of longer duration when including a super-subject design (Ford et al., J Nutr 2020;150:411-8) and/or studying retinol kinetics.

Influence of Vitamin A Status on the Choice of Sampling Time for Application of the Retinol Isotope Dilution Method in Theoretical Children.

BACKGROUND: Vitamin A status may influence the choice of a blood sampling time for applying the retinol isotope dilution (RID) equation to predict vitamin A total body stores (TBS) in children. OBJECTIVES: We aimed to identify time(s) after administration of labeled vitamin A that provide accurate estimates of TBS in theoretical children with low or high TBS. METHODS: We postulated 2- to 5-y-old children (12/group) with low (<200 µmol) or high TBS (≥700 µmol) and used compartmental analysis to simulate individual subject values for the RID equation TBS =   FaS/SAp (Fa, fraction of dose in stores; S, retinol specific activity in plasma/in stores; SAp, retinol specific activity in plasma). Using individual SAp and group geometric mean FaS values from 1-28 d, we calculated individual and group mean TBS and compared them to assigned values. RESULTS: Mean TBS was accurately predicted for both groups at all times. For individuals, predicted and assigned TBS were closest when the CV% for FaS was low [12-14%; 4-13 d (low), 12-28 d (high)]. The mean percentage error for TBS was <10% from 2-19 d (low) and 7-28 d (high). Predicted TBS was within 25% of assigned TBS for ≥80% of children from 3-23 d (low) and 9-28 d (high). Within groups, RID tended to overestimate lower TBS and underestimate higher TBS. CONCLUSIONS: Using a good estimate for FaS, accurate RID predictions of TBS for individuals will be obtained at many times. If vitamin A status is low, results indicate that early sampling (e.g., 4-13 d) is optimal; if vitamin A status is high, sampling at 12-28 d is indicated. When vitamin A status is unknown, sampling at 14 d is recommended, or a super-subject design can be used to obtain the group mean FaS at various times for RID prediction of TBS in individuals.

Prevalence of Food-Hypersensitivity and Food-Dependent Anaphylaxis in Colombian Schoolchildren by Parent-Report.

Background and objectives: The epidemiology of food allergy (FA) and food-dependent anaphylaxis remains unknown in Colombia. Our aim was to estimate by parent-report the prevalence of FA and food-dependent anaphylaxis in a Colombian population of schoolchildren. Materials and methods: A printed questionnaire was sent to parents of schoolchildren aged 5-12 years old from Medellín, Colombia in order to collect FA-related data. Results: Nine hundred and sixty-nine (969) parents returned the questionnaire with valid responses (response rate, 52.5%). The estimated prevalence rates (95% CI) were: adverse food reactions 12.79% (10.76-15.07), "perceived FA, ever" 10.93% (9.08-13.08), "physician-diagnosed FA, ever" 4.33% (3.14-5.81), "immediate-type FA, ever" 6.81% (5.30-8.58), "immediate-type FA, current" 3.30% (2.26-4.63), and food-dependent anaphylaxis 1.85% (1.10-2.92). The most frequently reported food allergens were milk (1.44%), fruits (0.41%), meat (0.41%), and peanut (0.3%). Sixty-one percent of "food-dependent anaphylaxis" cases sought medical attention, but only eleven percent of the cases reported the prescription of an epinephrine autoinjector. Conclusions: FA and food-dependent anaphylaxis are not uncommon among schoolchildren from Colombia. The prescription of epinephrine autoinjectors should be encouraged among health personnel for the optimal management of suspected cases of food-dependent anaphylaxis.

The "Super-Child" Approach Is Applied To Estimate Retinol Kinetics and Vitamin A Total Body Stores in Mexican Preschoolers.

BACKGROUND: Retinol isotope dilution (RID) and model-based compartmental analysis are recognized techniques for assessing vitamin A (VA) status. Recent studies have shown that RID predictions of VA total body stores (TBS) can be improved by using modeling and that VA kinetics and TBS in children can be effectively studied by applying population modeling ("super-child" approach) to a composite data set. OBJECTIVES: The objectives were to model whole-body retinol kinetics and predict VA TBS in a group of Mexican preschoolers using the super-child approach and to use model predictions of RID coefficients to estimate TBS by RID in individuals. METHODS: Twenty-four healthy Mexican children (aged 3-6 y) received an oral dose (2.96 µmol) of [13C10]retinyl acetate in corn oil. Blood samples were collected from 8 h to 21 d after dosing, with each child sampled at 4 d and at 1 other time. Composite data for plasma labeled retinol compared with time were analyzed using a 6-component model to obtain group retinol kinetic parameters and pool sizes. Model-predicted TBS was compared with mean RID predictions at 4 d; RID estimates at 4 d were compared with those calculated at 7-21 d. RESULTS: Model-predicted TBS was 1097 µmol, equivalent to ∼2.4 y-worth of VA; using model-derived coefficients, group mean RID-predicted TBS was 1096 µmol (IQR: 836-1492 µmol). TBS at 4 d compared with a later time was similar (P = 0.33). The model predicted that retinol spent 1.5 h in plasma during each transit and recycled to plasma 13 times before utilization. CONCLUSIONS: The super-child modeling approach provides information on whole-body VA kinetics and can be used with RID to estimate TBS at any time between 4 and 21 d postdose. The high TBS predicted for these children suggests positive VA balance, likely due to large-dose VA supplements, and warrants further investigation.

Bioelectric Impedance Vector Analysis (BIVA) in Breast Cancer Patients: A Tool for Research and Clinical Practice.

Background and objectives: Body composition assessment can provide information associated with breast cancer patients' (BCP) prognosis, that can lead interventions to improve survival outcomes. The aim of this study was to evaluate the effect of an individualized nutrition intervention program on breast cancer patients using bioelectrical impedance vector analysis (BIVA). Materials and Methods: This is a pretest-posttest study in recently diagnosed nonmetastatic BCP undergoing antineoplastic treatment, free of co-morbidities and dietary supplementation. Body composition was assessed at baseline and 6 months after an individualized nutrition intervention program, by dual-energy X-ray absorptiometry and BIVA. According to BIVA, each participant was located in the bivariate tolerance ellipses for Mexican population (50%, 75%, and 95%). In clinical practice, the 50% and 75% ellipses are considered within normality ranges. Results: Nine nonmetastatic BCP completed the intervention and were included in the analysis. After the intervention, they decreased by 5.8 kg of body weight (IQR, 3-6; p < 0.05), 3.8 kg of fat mass (IQR, 0.1-4.2; p < 0.05), and 1.4 kg of fat-free mass (IQR, -0.1 to 4; p < 0.05) while appendicular skeletal muscle mass remained unchanged (-0.2 kg, IQR, -0.8 to 2.3; p = 0.4). Using BIVA at baseline, five participants were among the 50% and 75% ellipses, mainly located in the area corresponding to edema and low lean tissue, two in the cachexia quadrant and two in the athletic quadrant (≥95% ellipse). After 6 months of intervention, six out of nine participants were in the athletic quadrant and eight of nine BCP were above the 5° phase angle cut-off point. One patient initially presented cachexia (≥95% ellipse); at postintervention her vector changed to the 50% ellipse. Conclusions: An individualized nutrition intervention program designed for nonmetastatic BCP was effective to improve the nutritional status of BCP as assessed by BIVA, therefore BIVA can be a useful tool to monitor changes in nonmetastatic BCP body composition in research and clinical practice.

Use of a "Super-child" Approach to Assess the Vitamin A Equivalence of Moringa oleifera Leaves, Develop a Compartmental Model for Vitamin A Kinetics, and Estimate Vitamin A Total Body Stores in Young Mexican Children.

Background: Worldwide, an estimated 250 million children <5 y old are vitamin A (VA) deficient. In Mexico, despite ongoing efforts to reduce VA deficiency, it remains an important public health problem; thus, food-based interventions that increase the availability and consumption of provitamin A-rich foods should be considered.Objective: The objectives were to assess the VA equivalence of 2H-labeled Moringa oleifera (MO) leaves and to estimate both total body stores (TBS) of VA and plasma retinol kinetics in young Mexican children.Methods: ß-Carotene was intrinsically labeled by growing MO plants in a 2H2O nutrient solution. Fifteen well-nourished children (17-35 mo old) consumed puréed MO leaves (1 mg ß-carotene) and a reference dose of [13C10]retinyl acetate (1 mg) in oil. Blood (2 samples/child) was collected 10 times (2 or 3 children each time) over 35 d. The bioefficacy of MO leaves was calculated from areas under the composite "super-child" plasma isotope response curves, and MO VA equivalence was estimated through the use of these values; a compartmental model was developed to predict VA TBS and retinol kinetics through the use of composite plasma [13C10]retinol data. TBS were also estimated with isotope dilution.Results: The relative bioefficacy of ß-carotene retinol activity equivalents from MO was 28%; VA equivalence was 3.3:1 by weight (0.56 µmol retinol:1 µmol ß-carotene). Kinetics of plasma retinol indicate more rapid plasma appearance and turnover and more extensive recycling in these children than are observed in adults. Model-predicted mean TBS (823 µmol) was similar to values predicted using a retinol isotope dilution equation applied to data from 3 to 6 d after dosing (mean ± SD: 832 ± 176 µmol; n = 7).Conclusions: The super-child approach can be used to estimate population carotenoid bioefficacy and VA equivalence, VA status, and parameters of retinol metabolism from a composite data set. Our results provide initial estimates of retinol kinetics in well-nourished young children with adequate VA stores and demonstrate that MO leaves may be an important source of VA.

Amaranth Protein Hydrolysates Efficiently Reduce Systolic Blood Pressure in Spontaneously Hypertensive Rats.

Alcalase is the enzyme of choice to release antihypertensive peptides from amaranth proteins, but the hydrolysis conditions have not been optimized yet. Furthermore, in vivo assays are needed to confirm such a hypotensive effect. Our aim was to optimize the hydrolysis of amaranth protein with alcalase and to test in vivo the hypotensive effect of the hydrolysates. A response surface analysis was carried out to optimize the hydrolysis reaction. The response variable was the Angiotensin Converting Enzyme (ACE-I) inhibition. The hydrolysis degree was determined (free alpha-amino groups measurement). The optimized hydrolysate bioavailability was assessed in the sera of mice and the hypotensive effect was assessed in spontaneously hypertensive rats. Control groups were administered captopril or water. The optimized hydrolysis conditions were: pH = 7.01, temperature = 52 °C, enzyme concentration 0.04 mU/mg, and time = 6.16 h. The optimized hydrolysate showed a 93.5% of ACE-I inhibition and a hydrolysis degree of 74.77%. After supplementation, the hydrolysate was bioavailable in mice from 5 to 60 min, and the hypotensive effect started at 4 h in spontaneously hypertensive rats (p < 0.05 vs. water group). This effect was similar to the captopril hypotensive effect for the next 3 h (p > 0.05). The use of amaranth-optimized hydrolysates as hypotensive supplements or ingredient for functional foods seems feasible.

International experiences in assessing vitamin A status and applying the vitamin A-labeled isotope dilution method.

Inadequate vitamin A (VA) nutrition continues to be a major problem worldwide, and many interventions being implemented to improve VA status in various populations need to be evaluated. The interpretation of results after an intervention depends greatly on the method selected to assess VA status. To evaluate the effect of an intervention on VA status, researchers in Cameroon, India, Indonesia, Mexico, Senegal and Zambia have used serum retinol as an indicator, and have not always found improvement in response to supplementation. One problem is that homeostatic control of serum retinol may mask positive effects of treatment in that changes in concentration are observed only when status is either moderately to severely depleted or excessive. Because VA is stored mainly in the liver, measurements of hepatic VA stores are the “gold standard” for assessing VA status. Dose response tests such as the relative dose response (RDR) and the modified relative dose response (MRDR), allow a qualitative assessment of VA liver stores. On the other hand, the use of the vitamin A-labeled isotope dilution (VALID) technique, (using 13C or 2H-labeled retinyl acetate) serves as an indirect method to quantitatively estimate total body and liver VA stores. Countries including Cameroon, China, Ghana, Mexico, Thailand and Zambia are now applying the VALID method to sensitively assess changes in VA status during interventions, or to estimate a population’s dietary requirement for VA. Transition to the use of more sensitive biochemical indicators of VA status such as the VALID technique is needed to effectively assess interventions in populations where mild to moderate VA deficiency is more prevalent than severe deficiency.

Nutritional interventions in children with acute lymphoblastic leukemia undergoing antineoplastic treatment: a systematic review.

BACKGROUND: A compromised nutritional status jeopardizes a positive prognosis in acute lymphoblastic leukemia (ALL) patients. In low- and middle-income countries, ~ 50% of children with ALL are malnourished at diagnosis time, and undergoing antineoplastic treatment increases the risk of depleting their nutrient stores. Nutrition interventions are implemented in patients with cancer related malnutrition. We aimed to evaluate the effect of nutrition interventions in children diagnosed with ALL under treatment. METHODS: Using a predefined protocol, we searched for published or unpublished randomized controlled trials in: Cochrane CENTRAL, MEDLINE, EMBASE, LILACS, and SciELO, and conducted complementary searches. Studies where at least 50% of participants had an ALL diagnosis in children ≤ 18 years, active antineoplastic treatment, and a nutrition intervention were included. Study selection and data extraction were conducted independently by three reviewers, and assessment of the risk of bias by two reviewers. Results were synthesized in both tabular format and narratively. RESULTS: Twenty-five studies (out of 4097 records) satisfied the inclusion requirements. There was a high risk of bias in eighteen studies. Interventions analyzed were classified by compound/food (n = 14), micronutrient (n = 8), and nutritional support (n = 3). Within each group the interventions and components (dose and time) tested were heterogeneous. In relation to our primary outcomes, none of the studies reported fat-free mass as an outcome. Inflammatory and metabolic markers related to nutritional status and anthropometric measurements were reported in many studies but varied greatly across the studies. For our secondary outcomes, fat mass or total body water were not reported as an outcome in any of the studies. However, some different adverse events were reported in some studies. CONCLUSIONS: This review highlights the need to conduct high-quality randomized controlled trials for nutrition interventions in children with ALL, based on their limited number and heterogeneous outcomes. REGISTRATION OF THE REVIEW PROTOCOL: Guzmán-León AE, Lopez-Teros V, Avila-Prado J, Bracamontes-Picos L, Haby MM, Stein K. Protocol for a Systematic Review: Nutritional interventions in children with acute lymphoblastic leukemia undergoing an tineoplastic treatment. International prospective register of systematic reviews. 2021; PROSPERO CRD:42,021,266,761 ( https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=266761 ).

Vitamin A-fortified milk increases total body vitamin A stores in Mexican preschoolers.

Vitamin A (VA) deficiency (VAD) continues to be a major nutritional problem in developing countries, including Central America. In Mexico, milk is a well-accepted vehicle for the administration of micronutrients, including VA, to preschoolers. Thus, we conducted a randomized, controlled, clinical trial to investigate the efficacy of daily consumption of 250 mL of VA-fortified milk (which provided 196 retinol equivalents/d) for 3 mo on VA stores in mildly to moderately VAD (serum retinol concentration 0.35-0.7 µmol/L) preschoolers who were not enrolled in a food assistance program. Twenty-seven mildly to moderately VAD children were randomly assigned based on screening measurements to either the intervention (n = 14) or control group (n = 13) (children in the control group did not receive placebo). All children in the control group and 79% (n = 11) of the children in the intervention group completed the study. The total body VA (TBVA) pool size was estimated using the deuterated retinol dilution technique before and after the intervention. After 3 mo, median changes in the serum retinol concentration for the intervention and control groups were 0.13 and -0.21 µmol/L, respectively (P = 0.009). Median changes in the TBVA stores were 0.06 and 0.01 mmol, respectively (P = 0.006) and estimated median changes in the liver VA concentration were 0.09 and 0.01 µmol/g, respectively (P = 0.002). The VA-fortified milk was well accepted among preschoolers and significantly increased TBVA stores, liver VA stores, and serum retinol concentration, indicating that it may be an effective means to ameliorate VAD in young Mexican children.

A Food Matrix Triggers a Similar Allergic Immune Response in BALB/c Mice Sensitized with Native, Denatured, and Digested Ovalbumin.

The search for an animal model to evaluate the allergenic potential of processed food products is still ongoing. Both the sensitization to ovalbumin (OVA) in different structural states and the allergic response triggered after intragastric or food challenges were assessed. BALB/c mice were sensitized intraperitoneally to OVA (50 µg) in different structural states (native OVA, N-OVA; denatured OVA, D-OVA; formaldehyde- and lysine-treated OVA, FK-OVA; denatured OVA-FK, OVA-DFK; peptides from pepsin digestion, Pep-OVA). Anti-OVA-specific IgE responses were evaluated using ELISA. Anaphylactic signs and mMCP-1 serum levels were evaluated after intragastric (2.0 mg/OVA) and food (0.41 mg/OVA) challenges. IgE reactivities to N-OVA and D-OVA were similar among groups (p > 0.05). After the challenges, all OVA-sensitized mice developed mild to severe anaphylactic signs (p < 0.05 vs. control). Mice sensitized to N-OVA and D-OVA had the highest mMCP-1 serum levels after challenges (p < 0.05 vs. control). Allergic responses were similar despite the different OVA doses used for the challenges. The N-OVA-sensitized murine model of egg allergy proposed in the present study holds the potential for evaluating the impact of food matrix composition and processing on the threshold of egg-allergic responses.

Assessment of the Route of Exposure to Ovalbumin and Cow's Milk Proteins on the Induction of IgE Responses in BALB/c Mice.

BALB/c mice can be orally sensitized to food proteins under acid suppressive medication, mimicking human exposure and triggering a human-like allergic immune response. However, the reproducibility of such an oral food allergy model remains questionable. Our aim was to evaluate the IgE responses triggered against ovalbumin (OVA) and cow's milk proteins (CMP) after intragastric (IG), either under gastric-acid suppression or not, or intraperitoneal (IP) sensitization in BALB/c mice. OVA (0.2 mg) and different concentrations of CMP were administered with/without the antacid sucralfate by the IG route. For IP sensitization, OVA or CMP (0.5 mg) were administered. ELISA was used to evaluate IgE responses. The IP sensitization protocols triggered more robust and consistent anti-OVA or anti-CMP IgE responses than the intragastric ones (with/without sucralfate) (p < 0.05). 2.7% (1/36), and 5.5% (3/54) of the mice that underwent the sucralfate-assisted IG protocol triggered IgE responses against OVA or CMP, respectively. All the mice were administered OVA or CMP via IP triggered detectable IgE responses. The IP sensitization model is more reliable than the IG one for evaluating the intrinsic sensitizing and/or allergenic potential of food proteins, even if IG immunizations are carried out under gastric-acid suppression.

An individualized food-based nutrition intervention reduces visceral and total body fat while preserving skeletal muscle mass in breast cancer patients under antineoplastic treatment.

BACKGROUND & AIMS: Breast cancer patients (BCP) during treatment often experience an increase in body weight and fat mass, and a decrease in muscle mass known as sarcopenic obesity, affecting their prognosis and quality of life. We aimed to evaluate the effect of a 6-month individualized food-based nutrition intervention program in nonmetastatic BCP body composition during treatment. METHODS: This is a pre-post study in recently diagnosed women with invasive ductal/lobular breast carcinoma (clinical stage I-III). The individualized nutrition intervention was based on the dynamic macronutrient meal equivalent menu method (MEM). Dietary plans were developed according to WCRF/AICR guidelines, BCP total energy expenditure, 1.2-1.5 g/kgBW/d of protein intake, 5-9 servings/day of fruits and vegetables, and a caloric restriction (500-1000 kcal/d) when applicable (BMI ≥ 25 kg/m2). Follow-up was every 2-weeks and a different diet menu was provided in each session during 6 months. Baseline and final measurements included the assessment of anthropometry, body composition, and physical activity. RESULTS: Twenty-two participants completed the study and at diagnosis 68% were overweighed or obese. After the 6-month nutrition intervention program, BCP lost 3.1 kg (p < 0.01) of body weight, 2.7 kg (p < 0.01) of fat-mass, 400 g (p < 0.01) of abdominal fat, 118 g (p < 0.05) of visceral fat, 1.2 kg/m2 of body mass index and 1.1 kg/m2 of fat mass index (p < 0.01). During the period, no changes were observed in bone mineral density (p = 0.3), fat-free mass (p = 0.1) and appendicular skeletal muscle mass (p = 0.2). Menopausal status in BCP did not modify the effect of the nutrition intervention. CONCLUSIONS: The individualized food-based nutrition intervention program empowered BCP to make informed healthy food choices within their personal preferences, socioeconomic and cultural background. With this type of intervention, nonmetastatic BCP reduced body weight, fat-mass, fat mass index, visceral and abdominal fat, while preserving skeletal muscle mass, during antineoplastic treatment. ClinicalTrials.govNCT03625635.

Giardia lamblia infection and its implications for vitamin A liver stores in school children.

BACKGROUND: Vitamin A deficiency (VAD) is a nutritional problem affecting the health of people in developing countries because VAD compromises innate and adaptive immunity, increasing a person's predisposition toward infectious diseases. In addition, a high prevalence of infectious diseases continues to be a problem in developing countries, including Giardia lamblia. G. lamblia may be related to VAD because of its ability to change the intestinal architecture, thereby compromising the absorption of vitamin A. The aim of this study was to evaluate the effect of giardiasis on serum retinol levels and vitamin A liver stores in school children. METHODS: Thirty Giardia-infected school children participated in this study. Vitamin A liver stores were evaluated with the modified relative dose response (MRDR) technique, and antiparasitic treatment was administered. In addition, anthropometric and dietary data were collected. RESULTS: According to anthropometric indicators (age-appropriate Z scores for weight, height and body mass index) and daily vitamin A intake, the children had a normal nutritional status. Although the mean serum retinol levels did not change significantly after treatment for Giardia (p > 0.05), the MRDR values showed significant improvement (p < 0.002). CONCLUSION: Giardiasis not only compromises the vitamin A status through intestinal malabsorption, it also causes profound mobilization of liver retinol stores.