Betaglucanos de «Pleurotus ostreatus» en la prevención de infecciones respiratorias recurrentes / Beta-glucans from Pleurotus ostreatus for prevention of recurrent respiratory tract infections

Introducción: Las infecciones del tracto respiratorio (ITR) recurrentes (ITRR) representan uno de los motivos más frecuentes de consulta en la práctica pediátrica. En estos casos, la suplementación con derivados naturales como los betaglucanos se ha propuesto como una intervención inmunomoduladora a nivel celular y humoral, que favorecería una menor frecuencia de aparición de episodios. Pacientes y métodos: Estudio multicéntrico, observacional y prospectivo de pacientes de 20 consultas pediátricas de Alicante, Barcelona y Valencia que, según la frecuencia de ITR del año previo, se clasificaron como ITRR. Se recomendó una dosis diaria de una solución oral a base de betaglucanos procedentes de Pleurotus ostreatus y vitamina C durante 3 meses. Se compararon el número y el tipo de episodios de ITR en el periodo de octubre a marzo del año previo con los observados durante los 6 meses de estudio, entre otras variables relacionadas. Resultados: Se obtuvieron datos de 151 niños, observándose reducciones significativas tras la suplementación tanto en la media de episodios (8,88 ± 3,35 frente a 4,27 ± 2,21; p <0,001) como en el riesgo de continuar cumpliendo criterios de ITRR (riesgo relativo= 0,36; intervalo de confianza del 95%: 0,3-0,45). Se observó que las visitas a urgencias, la necesidad de tratamiento farmacológico y las faltas a guardería/colegio también fueron menos frecuentes durante el periodo de estudio, además de una menor tasa de incidencia y un menor número de episodios según los tipos de ITR (otitis, resfriados comunes, faringoamigdalitis, laringitis y bronquitis). El 90,7% de los casos presentaron una tolerabilidad buena o muy buena. La mejoría percibida por los padres se estimó en un 85,7%. Conclusiones: En ausencia de medidas para la inmunización activa contra los patógenos más frecuentemente asociados a procesos infecciosos de las vías respiratorias, los resultados sugieren que la suplementación profiláctica con betaglucanos procedentes de P. ostreatus y vitamina C podría ser beneficiosa, particularmente en niños con un patrón recurrente y factores de riesgo específicos (AU)

Introduction: Respiratory tract infections (RTI) are one of the most common reasons for medical visits in paediatric clinical practice. In cases of recurrence, supplementation with natural derivatives such as β-glucans has been proposed as an immunomodulatory intervention which based on its effects on humoral and cell-mediated immune responses, might reduce frequency of respiratory tract infections (RTIs). Patients and methods: A prospective observational multicenter study of patients from 20 paediatric clinics of Alicante, Barcelona and Valencia who were considered with RRI according to the number of RTI during the previous year. Supplementation with a daily dose of a β-glucans from Pleurotus ostreatus and vitamin C for 3 months was recommended. Comparison between the number and type of RTI during the previous October-period, among other variables, were compared with those observed during the 6-month follow-up. Results: Analysis of data from 151 children have shown significant reductions on the average number of RTIs episodes (4.27 ± 2.21 vs. 8.88 ± 3.35; p <0.001) and the risk of been considered as RRI (RR [95%CI]: 0.36 [0.3-0.45]; p <0.0001) after the supplementation. Visits to the Emergency department, use of pharmacological treatment and missed school days were also less frequent when compared with the previous year. Each of the RTI subtypes (otitis, common cold, pharyngitis, laryngitis and bronchitis) showed significant reductions both on incidence and number of episodes. A 90.7% of cases reported a good or very good tolerability and the improvement perceived was reported in 85.7% of parents. Conclusions: In absence of measures for active immunization against pathogens most frequently associated with respiratory infections, prophylactic supplementation β-glucans from Pleurotus ostreatus and vitamin C has may be of benefit particularly in children with recurrences and specific risk factors (AU)

The effect of a partially hydrolysed formula based on rice protein in the treatment of infants with cow's milk protein allergy.

Infants diagnosed with allergy to cow's milk protein (CMP) are fed extensively hydrolysed cow's milk formulas, modified soy formulas or even amino acid-based formulas. Hydrolysed rice protein infant formulas have become available and have been shown to be well tolerated by these infants. A prospective open, randomized clinical study to compare the clinical tolerance of a new hydrolysed rice protein formula (HRPF) with an extensively hydrolysed CMP formula (EHF) in the feeding of infants with IgE-mediated cow's milk allergy. Ninety-two infants (46 boys and 46 girls, mean age 4.3 months, range 1.1-10.1 months) diagnosed with IgE-mediated cow's milk allergy were enrolled in the study. Clinical tolerance to the formula products was tested. Clinical evaluation included skin prick tests with whole cow's milk, soya and rice as well as antigens of CMP (beta-lactoglobulin, alpha-lactalbumin, casein and bovine seroalbumin), HRPF and EHF and specific IgE determinations to CMP using CAP technology. Patients were randomized to receive either an EHF based on CMP or a new HRPF. Follow-up was at 3, 6, 12, 18 and 24 months. Growth parameters were measured at each visit. One infant showed immediate allergic reaction to EHF, but no reaction was shown by any infant in the HRPF group. The number of infants who did not become tolerant to CMP during the study was not statistically different between the two groups. Measurement of IgE levels of infants allergic to CMP during the study showed no significant differences between the two formula groups. Growth parameters were in the normal range and similar between groups. In this study, the HRPF was well tolerated by infants with moderate to severe symptoms of IgE-mediated CMP allergy. Children receiving this formula showed similar growth and development of clinical tolerance to those receiving an EHF. In accordance with current guidelines, this HRPF was tolerated by more than 90% of children with CMP allergy and therefore could provide an adequate and safe alternative to CMP-hydrolysed formulas for these infants.

[The importance of functional ingredients in pediatric milk formulas and cereals]. / La importancia de los ingredientes funcionales en las leches y cereales infantiles.

Feeding during the first months of life has a decisive influence not only in early developmental phases of children but also in their long-term health. Therefore, inclusion of new functional ingredients to pediatric milk formulas is, nowadays, the matter of a number of studies, incorporating day-by-day newer products and more similar to human milk, the gold standard, which contains them in a natural way. Nowadays, technological advances have made possible to obtain these ingredients from animal or vegetal sources for their addition into pediatric milk formulas and cereals. In the present article, the main functional ingredients, such as polyunsaturated fatty acids, palmitate, nucleotides, pre- and probiotic oligosaccharides, carnitine and taurine are reviewed with regards to their nutritional and functional interest in infant feeding. Their incorporation in pediatric foods has been possible after carrying out animal and clinical studies that provide a solid scientific basis which guaranties their proper bioavailability and their efficacy in the newborn. In the future years, thanks to a better understanding of maternal milk composition and to the performance of further studies, it will be possible to add new ingredients that will allow to obtain pediatric milk formulas more and more similar to maternal milk from a nutritional and functional point of view.

La importancia de los ingredientes funcionales en las leches y cereales infantiles / The importance of functional ingredients in pediatric milk formulas and cereals

La alimentación durante los primeros meses de vida tiene una influencia decisiva no sólo en las fases tempranas del desarrollo del niño sino también en su salud a largo plazo. Por ello, la incorporación de nuevos ingredientes funcionales a las leches infantiles es hoy objeto de numerosos estudios, dando cada vez productos más novedosos y semejantes a la leche humana, patrón de oro, que los contiene en forma natural. Hoy día, los avances tecnológicos han permitido la obtención de estos ingredientes a partir de fuentes de tipo animal o vegetal para su adición en leches y cereales infantiles. En el presente estudio se revisa el interés nutricional y funcional de los principales ingredientes funcionales de interés en la alimentación del lactante, como son los ácidos grasos poliinsaturados, b-palmitato, nucleótidos, oligosacáridos con efecto prebiótico, probióticos, carnitina y taurina. Su incorporación en los alimentos infantiles ha sido posible tras la realización de estudios en animales y estudios clínicos que proporcionan una sólida base científica que garantiza tanto su correcta biodisponibilidad como su eficacia en el recién nacido. En el futuro, gracias a un mayor conocimiento de la composición de la leche materna y a la realización de estudios adicionales será posible la incorporación de nuevos ingredientes que permitan la obtención de leches infantiles cada vez más similares a nivel nutricional y funcional a la leche materna (AU)

Feeding during the first months of life has a decisive influence not only in early developmental phases of children but also in their long-term health. Therefore, inclusion of new functional ingredients to pediatric milk formulas is, nowadays, the matter of a number of studies, incorporating day-by-day newer products and more similar to human milk, the gold standard, which contains them in a natural way. Nowadays, technological advances have made possible to obtain these ingredients from animal or vegetal sources for their addition into pediatric milk formulas and cereals. In the present article, the main functional ingredients, such as polyunsaturated fatty acids, palmitate, nucleotides, preand probiotic oligosaccharides, carnitine and taurine are reviewed with regards to their nutritional and functional interest in infant feeding. Their incorporation in pediatric foods has been possible after carrying out animal and clinical studies that provide a solid scientific basis which guaranties their proper bioavailability and their efficacy in the newborn. In the future years, thanks to a better understanding of maternal milk composition and to the performance of further studies, it will be possible to add new ingredients that will allow to obtain pediatric milk formulas more and more similar to maternal milk from a nutritional and functional point of view (AU)

Fatty acid and sn-2 fatty acid composition in human milk from Granada (Spain) and in infant formulas.

OBJECTIVE: To investigate differences in fatty acid and sn-2 fatty acid composition in colostrum, transitional and mature human milk, and in term infant formulas. SETTING: Departament de Nutrició i Bromatologia, University of Barcelona, Spain and University Hospital of Granada, Spain. SUBJECTS: One-hundred and twenty mothers and 11 available types of infant formulas for term infants. DESIGN: We analysed the fatty acid composition of colostrum (n=40), transitional milk (n=40), mature milk (n=40) and 11 infant formulas. We also analysed the fatty acid composition at sn-2 position in colostrum (n=12), transitional milk (n=12), mature milk (n=12), and the 11 infant formulas. RESULTS: Human milk in Spain had low saturated fatty acids, high monounsaturated fatty acids and high linolenic acid. Infant formulas and mature human milk had similar fatty acid composition. In mature milk, palmitic acid was preferentially esterified at the sn-2 position (86.25%), and oleic and linoleic acids were predominantly esterified at the sn-1,3 positions (12.22 and 22.27%, respectively, in the sn-2 position). In infant formulas, palmitic acid was preferentially esterified at the sn-1,3 positions and oleic and linoleic acids had higher percentages at the sn-2 position than they do in human milk. CONCLUSION: Fatty acid composition of human milk in Spain seems to reflect the Mediterranean dietary habits of mothers. Infant formulas resemble the fatty acid profile of human milk, but the distribution of fatty acids at the sn-2 position is markedly different.

Oligosaccharides: application in infant food.

Oligosaccharides are a complex mixture of approximately 130 compounds present in human milk. It has been shown that human milk oligosaccharides induce an increase in the number of bifidobacteria of colonic flora in breast-fed infants, accompanied with a significant reduction in the number of pathogenic potential bacteria, due to their bifidogenic activity. Complex oligosaccharides have the capacity of inhibiting the binding of pathogens to cell surface because they act as competitive receptors. They are associated with a lower risk of infections and diarrhoea and an improvement of the immune system response. Due to the decrease of the pH intestinal caused by their fermentation, oligosaccharides provoke a reduction of the flora pathogens, an increase of bifidobacteria and an increase of the availability of minerals. In the food industry, simple oligosaccharides such as fructooligosaccharides and galactooligosaccharides are used as bifidogenic oligosaccharides and some infant products contain them in the hope that this might provide some of the benefits attributed to oligosaccharides in human milk. This paper reviews characteristics of oligosaccharides, their beneficial effects and use of oligosaccharides in the food industry. In adults, the benefits of some of the oligosaccharides have been established in several clinical trials, but in infants more fundamental research is needed to establish the metabolic role of these components and the daily intake with bifidogenic activity.

Plasma and erythrocyte alpha-tocopherol and plasma retinol concentrations in term infants fed formula enriched with long-chain polyunsaturated fatty acids.

OBJECTIVE: To assess the effect of long-chain polyunsaturated fatty acids (LCPUFA)- and vitamin E-supplemented formula feeding on erythrocyte and plasma alpha-tocopherol (VE), and plasma retinol (VA) concentrations in neonates and to compare these values with those found in infants feeding on infant formula without LCPUFA or breast milk SETTING: University Hospital of Granada, Spain. SUBJECTS: 49 full-term infants. DESIGN AND INTERVENTION: Subjects who chose not to breast feed were fed either (i) unsupplemented infant formula (F) or (ii) infant formula supplemented with LCPUFA and vitamin E (FL). Alpha-tocopherol and retinol were measured at 7 days, 1 month and 3 months. RESULTS: Plasma and erythrocyte VE concentrations and plasma VE/total lipids ratio increased significantly in all groups at 1 month of life (P < 0.05), but did not change significantly between 1 month and 3 months in any group (P > 0.05). Erythrocyte VE and VA retinol concentrations were higher in infants fed an infant formula than in breast milk-fed infants at 1 month of life (P < 0.05). Finally, there were no significant differences in plasma or erythrocyte VE levels, plasma VA or plasma VE/total lipid ratio between any groups at 3 months of life (P > 0.05). CONCLUSION: Infants fed on LCPUFA- and vitamin E-supplemented infant formula for 3 months have similar vitamin E and A status to infants fed on breast milk or infant formula without LCPUFA supplementation.

Comparison of two methods for the determination of fatty acid profiles in plasma and erythrocytes.

We have validated and compared two methods for the determination of fatty acid profiles in biological samples by capillary gas chromatography. Method I consisted of a previous lipid extraction and esterification of fatty acids using boron trifluoride-methanol. Method II was a direct method that combined extraction and esterification of freeze-dried samples in a single step, using acetyl chloride as the reagent. The two methods were applied to the analysis of plasma and erythrocyte samples. Both methods gave similar results in plasma, whereas in erythrocytes, the direct method gave significantly higher contents of total fatty acids. Precision and recovery rates were determined and the results were satisfactory. Detection and quantification limits showed that both methods had excellent sensitivity. It was concluded that the direct method has substantial advantages over the conventional method, such as higher values in erythrocytes, rapidity and less possibility of contamination or fatty acid losses. Therefore, it is preferable for the analysis of biological samples such as plasma and erythrocytes.

Fatty acid composition of plasma and erythrocytes in term infants fed human milk and formulae with and without docosahexaenoic and arachidonic acids from egg yolk lecithin.

Human milk contains small but nutritionally significant amounts of long-chain polyunsaturated fatty acids (LCP), such as arachidonic (AA, 20:4n-6) and docosahexaenoic (DHA, 22:6n-3) acids, which are not present in most infant formulae. In the present study, the fatty acid composition of plasma and erythrocytes was determined at birth and again at 7 days, 1 and 3 months in 49 healthy full-term infants (37-42 week's gestation). One group of infants was fed exclusively with human milk (n=16) and the others were randomly assigned to a standard term formula (F) (n=15) or the same formula with egg yolk lecithin providing DHA (0.15%) and AA (0.30%) (LCP-F) (n=18). Plasma and erythrocyte LCP values of the three dietary groups did not differ at 7 days of age, but the contents of DHA and AA in plasma and erythrocytes at 1 and 3 months were significantly lower (P<0.05) in infants fed non supplemented formula than in infants fed breast milk and supplemented formula. There were no differences in plasma or erythrocyte AA or DHA concentrations between the group fed breast milk and the group fed supplemented formula during the period studied.

Influence of caesarean delivery and maternal factors on fat-soluble vitamins in blood from cord and neonates.

We measured plasma and erythrocyte vitamin E (VE) and plasma vitamin A (VA) profiles in 48 full-term and 8 preterm pairs of neonates and their mothers at birth and we determined whether there is any relationship between maternal and umbilical cord for the nutrients measured. At the same time, we assessed the influence of the delivery type and neonate anthropometric measurements on maternal and cord blood VA and VE levels. We measured vitamin levels in vein and arterial blood in order to establish differences due to fetal metabolism. To determine the influence of pregnancy on vitamin levels, we compared the maternal results with data from a group of 13 non-pregnant women. Cord blood had lower plasma VE (arterial 275.8+/-71.7 microg/dl and vein 282.89+/-64.4 microg/dl values), erythrocyte VE (arterial 256.96+/-50.41 microg/dl packet cells and vein 257.41+/-44.35 microg/dl values), and VA levels (arterial 26.72+/-11.83 microg/dl and 27.15+/-10.05 microg/dl values) and a lower vitamin E/total lipids ratio (VE/LT) (arterial 1.60+/-0.4 and vein 1.62+/-0.3 values) than maternal blood (1474.62+/-424.51 microg/dl, 305.94+/-54.75 microg/dl packet cells, 41.03+/-18.83 microg/dl, 2.34+/-0.5, respectively). VA levels were higher in preterm than full-term neonates (P<0.05). Plasma and erythrocyte VE levels were not correlated in maternal blood but were correlated in neonates and infants (r>0.40; P<0.01). We found a good correlation between erythrocyte tocopherol of maternal and cord blood (r>0.40; P<0.01), although there was no correlation with plasma VE values. Cord vein plasma VE levels were higher than cord arterial blood measurements (P<0.01). The plasma VE and VE/LT of the mother and cord following vaginal delivery were higher than measurements from caesarean delivery (P<0.05), although erythrocyte levels were similar. The plasma VE level was higher in mothers at delivery than non-pregnant women.

Comparison of two methods for the determination of fatty acid profiles in plasma and erythrocytes.

We have validated and compared two methods for the determination of fatty acid profiles in biological samples by capillary gas chromatography. Method I consisted of a previous lipid extraction and esterification of fatty acids using boron trifluoride-methanol. Method II was a direct method that combined extraction and esterification of freeze-dried samples in a single step, using acetyl chloride as the reagent. The two methods were applied to the analysis of plasma and erythrocyte samples. Both methods gave similar results in plasma, whereas in erythrocytes, the direct method gave significantly higher contents of total fatty acids. Precision and recovery rates were determined and the results were satisfactory. Detection and quantification limits showed that both methods had excellent sensitivity. It was concluded that the direct method has substantial advantages over the conventional method, such as higher values in erythrocytes, rapidity and less possibility of contamination or fatty acid losses. Therefore, it is preferable for the analysis of biological samples such as plasma and erythrocytes.

Administration of low doses of fish oil derived N-3 fatty acids to elderly subjects.

OBJECTIVES: To assess the incorporation of n-3 polyunsaturated fatty acids (PUFA) in plasma and erythrocyte lipids of elderly subjects after ingestion of very low doses of fish oil. The effects on alpha-tocopherol and retinol concentrations were also studied. SETTING: Municipal nursing home in Barcelona, Spain. SUBJECTS: Forty-five elderly subjects aged 60-92 y. DESIGN AND INTERVENTION: Subjects received a non-commercialized milk formula containing 1% fish oil for 15 months, which provided 0.40 g/d of n-3 PUFA. Fatty acid profiles and antioxidant concentrations were measured before and after the intervention period. RESULTS: Fish oil ingestion was associated with significant increases in total n-3 PUFA in plasma and erythrocytes by 32% and 18%, respectively. Eicosapentaenoic (EPA) and docosahexaenoic (DHA) acid concentrations were higher after the ingestion period both in plasma and erythrocytes (P < 0.05), whereas linoleic and arachidonic acids remained unchanged. The n-6/n-3 ratio decreased by 21% in plasma and by 16% in erythrocytes (P < 0.05). Moreover, younger subjects showed a greater incorporation of EPA and DHA than older subjects. Plasma alpha-tocopherol and retinol concentrations did not vary significantly, whereas erythrocyte alpha-tocopherol was significantly higher after the intervention period. CONCLUSION: This study shows that low doses of n-3 PUFA supplemented with adequate amounts of alpha-tocopherol can be incorporated into blood lipids in elderly subjects without lowering their antioxidant concentrations.

Fatty acid composition of human milk in Spain.

The fatty acid composition of mature human milk obtained from 40 Spanish women was analyzed by capillary gas chromatography. The women were from two regions in Spain, Navarre and Catalonia. Milk samples were collected between 20 and 30 days postpartum. The fatty acid composition was expressed as weight percentage (% wt/wt of all fatty acids detected with a C8 to C22 chain length). Monounsaturated fatty acids represent 41.97%, mostly 18:1 n-9/n-7 (38.39%). The second major fraction was formed by saturated fatty acids, 41.09%. Polyunsaturated fatty acid fraction (15.23%), included seven long chain polyunsaturated fatty acids (LCPs; 2.21%). Among LCPs, 1.6% accounted for the n-6 series and 0.64% for the n-3 series. LCPn-6/LCPn-3 ratio was 2.51. Mothers reporting a high fish consumption showed higher (p < 0.05) 22:6 n-3 and 20:5 n-3 content. The use of olive oil as the preferential fat source showed higher 18:1 n-9/n-7 and lower 18:2 n-6 content (p < 0.0001), while the use of sunflower oil instead of olive oil significantly (p < 0.0001) increased 18:2 n-6 and decreased 18:1 n-9/n-7. Regional differences (p < 0.05) were detected only for the n-6 LCP and the total LCP content. The higher n-6 LCP and total LCP content was found in Navarre. This could have been due to different diet habits, like higher egg consumption.

Determination of alpha-tocopherol in plasma and erythrocytes by high-performance liquid chromatography.

A reversed-phase high-performance liquid chromatographic method for the determination of alpha-tocopherol in plasma or erythrocytes with photodiode-array detection is described. Using this detector, information about the spectrum, absorption maxima and purity of the peak is obtained. Tocopherol was separated on a 5-microns Spherisorb ODS-2 column with methanol as element at a flow-rate of 1.0 ml/min. As little as 100 microliters of plasma or 150 microliters of erythrocytes can be used for accurate analysis with direct extraction without saponification. The speed, specificity, sensitivity and reproducibility of this technique make it particularly suitable for the routine determination of alpha-tocopherol in plasma or erythrocytes.

Determination of sterol content in different food samples by capillary gas chromatography.

An accurate method for the determination of sterols by capillary gas chromatography was developed and applied to the analysis of food. The procedure includes the following steps: dichloromethane-methanol (2:1, v/v) lipid extraction, saponification at 80 degrees C and separation of the unsaponifiable matter with cyclohexane, derivatization to form trimethylsilyl ethers and gas chromatography using 5 alpha-cholestane as the internal standard. The method shows good accuracy, precision and sensitivity and is suitable for the determination of sterols in food.