Effect of Increasing Concentrations of Zinc on the Absorption of Iron from Iron-Fortified Milk

The cofortification of milk with iron (Fe) and zinc (Zn) is a strategy used to prevent these deficiencies during childhood. Given that Zn can negatively interact with iron in aqueous solutions, the objective of the present study was to determine the effect of Zn on Fe absorption of milk fortified with Fe and Zn. Twenty-eight women between 33 and 47?years of age, with contraception and a negative pregnancy test, participated in one of two absorption studies. They received on four different days, after an overnight fast, 200?mL of milk (26?% fat) fortified with 10?mg Fe/L, as (A) ferrous sulfate, or the same milk but with graded doses of added Zn, as Zn sulfate of (B) 5, (C) 10, and (D) 20?mg/L (study 1, n?=?15). In study 2 (n?=?13), subjects received the same milk formulations, but these were also fortified with ascorbic acid (70?mg/L). Milk was labeled with radioisotopes ⁵⁹Fe or ⁵⁵Fe, and the absorption of iron was measured by erythrocyte incorporation of radioactive Fe. The geometric mean and range of ±1 SD of Fe absorption in study 1 were as follows: formula A?=?6.0?% (2.8?C13.0?%); B?=?6.7?% (3.3?C13.6?%); C?=?5.4?% (2.2?C13.2?%); and D?=?5.2?% (2.8?C10.0?%) (ANOVA for repeated measures, not significant). For study 2, data are as follows: 8.2?% (3.6?C18.7?%); B?=?6.4?% (2.5?C16.4?%); C?=?7.7?% (3.2?C18.9?%); and D?=?5.2 (1.8?C14.8?%) (ANOVA for repeated measures, not significant). In conclusion, according to the results from this study, it appears that the addition of zinc up to 20?mg/L does not significantly inhibit iron absorption from milk fortified with 10?mg/L of iron.     

Non-heme Iron as Ferrous Sulfate Does Not Interact with Heme Iron Absorption in Humans

The absorption of heme iron has been described as distinctly different from that of non-heme iron. Moreover, whether heme and non-heme iron compete for absorption has not been well established. Our objective was to investigate the potential competition between heme and non-heme iron as ferrous sulfate for absorption, when both iron forms are ingested on an empty stomach. Twenty-six healthy nonpregnant women were selected to participate in two iron absorption studies using iron radioactive tracers. We obtained the dose?Cresponse curve for absorption of 0.5, 10, 20, and 50?mg heme iron doses, as concentrated red blood cells. Then, we evaluated the absorption of the same doses, but additionally we added non-heme iron, as ferrous sulfate, at constant heme/non-heme iron molar ratio (1:1). Finally, we compare the two curves by a two-way ANOVA. Iron sources were administered on an empty stomach. One factor analysis showed that heme iron absorption was diminished just by increasing total heme iron (P?<?0.0001). The addition of non-heme iron as ferrous sulfate did not have any effect on heme iron absorption (P?=?NS). We reported evidence that heme and non-heme iron as ferrous sulfate does not compete for absorption. The mechanism behind the absorption of these iron sources is not clear.     

Reducing endoplasmic reticulum stress does not improve steatohepatitis in mice fed a methionine- and choline-deficient diet

Endoplasmic reticulum (ER) stress has been implicated in the pathogenesis of nonalcoholic steatohepatitis. The ER stress response is activated in the livers of mice fed a methionine- and choline-deficient (MCD) diet, yet the role of ER stress in the pathogenesis of MCD diet-induced steatohepatitis is unknown. Using chemical chaperones on hepatic steatosis and markers of inflammation and fibrosis in mice fed a MCD diet, we aim to determine the effects of reducing ER stress. C57BL/6J mice were fed a MCD diet with or without the ER chemical chaperones 4-phenylbutyric acid (PBA) and tauroursodeoxycholic acid (TUDCA) for 2 wk. TUDCA and PBA effectively attenuated the ER stress response in MCD diet-fed mice, as evidenced by reduced protein levels of phosphorylated eukaryotic initiation factor 2α and phosphorylated JNK and suppression of mRNA levels of CCAAT/enhancer binding protein homologous protein, glucose-regulated protein 78 kDa, and X-box binding protein 1. However, PBA and TUDCA did not decrease MCD diet-induced hepatic steatosis. MCD diet-induced hepatic inflammation, as evidenced by increased plasma alanine aminotransferase and induction of hepatic TNFα expression, was also not reduced by PBA or TUDCA. PBA and TUDCA did not attenuate MCD diet-induced upregulation of the fibrosis-associated genes tissue inhibitor of metalloproteinase-1 and matrix metalloproteinase-9. ER chemical chaperones reduce MCD diet-induced ER stress, yet they do not improve MCD diet-induced hepatic steatosis, inflammation, or activation of genes associated with fibrosis. These data suggest that although the ER stress response is activated by the MCD diet, it does not have a primary role in the pathogenesis of MCD diet-induced steatohepatitis.     

Baja ingesta de yodo durante la gestación: Relación con el desarrollo placentario y el perímetro cefálico del recién nacido

IntroductionIodine is considered to be an essential micronutrient in pregnant women. Iodine placental transport to the embryo-fetus is essential for hormone synthesis and is crucial for nervous system development. However, the relationship between iodine intake and placental weight and its potential implications for the newborn have not been studied.Material and methodsIodine intake was analyzed in 77 pregnant women based on urinary iodine excretion (UIE) levels, measured using Pinós modified method (normal value, ≥ 150 μg/L). Placental weight was measured (PW: normal, ≥500 g). In the newborn, weight, height, and head perimeter (HP) were also measured. Placental index (PI: placental weight/newborn weight) was calculated, and was considered normal if ≥0.15.ResultsUIE was normal in 50 pregnant women (mean ± SD, 279 μg/L ± 70.22 μg/L) and decreased in 27 (94 μg/L ± 31.49 μg/L). Newborns of mothers with low UIE had a similar weight (3357 g ± 416.30 g; n: 27) to those of mothers with normal UIE (3489 g ± 560.59 g; n: 50). Forty-four percent of mothers with low UIE had PW <500 g, and statistically lower HPs were found in newborns of mothers with low PW (PW³500 g: 36.05 cm ± 0.55 cm, n: 54; PW <500 g: 33.93 cm ± 15 cm, n:23, p < 0.019). Similar results were found with PI, but they did not reach statistical significance (0,17 ± 0,04; p = 0.066). No differences were seen in all other parameters.ConclusionThe study suggests the existence of a relationship between PW and HP. This finding may be related to iodine intake during pregnancy.     

Oral Administration of Lactobacillus Strains Isolated from Breast Milk as an Alternative for the Treatment of Infectious Mastitis during Lactation

In this study, 20 women with staphylococcal mastitis were randomly divided in two groups. Those in the probiotic group daily ingested 10 log₁₀ CFU of Lactobacillus salivarius CECT5713 and the same quantity of Lactobacillus gasseri CECT5714 for 4 weeks, while those in the control one only ingested the excipient. Both lactobacillus strains were originally isolated from breast milk. On day 0, the mean staphylococcal counts in the probiotic and control groups were similar (4.74 and 4.81 log₁₀ CFU/ml, respectively), but lactobacilli could not be detected. On day 30, the mean staphylococcal count in the probiotic group (2.96 log₁₀ CFU/ml) was lower than that of the control group (4.79 log₁₀ CFU/ml). L. salivarius CECT5713 and L. gasseri CECT5714 were isolated from the milk samples of 6 of the 10 women of the probiotic group. At day 14, no clinical signs of mastitis were observed in the women assigned to the probiotic group, but mastitis persisted throughout the study period in the control group women. In conclusion, L. salivarius CECT5713 and L. gasseri CECT5714 appear to be an efficient alternative for the treatment of lactational infectious mastitis during lactation.     

Signaling lymphocytic activation molecule expression and regulation in human intracellular infection correlate with Th1 cytokine patterns.

Induction of Th1 cytokines, those associated with cell-mediated immunity, is critical for host defense against infection by intracellular pathogens, including mycobacteria. Signaling lymphocytic activation molecule (SLAM, CD150) is a transmembrane protein expressed on lymphocytes that promotes T cell proliferation and IFN-gamma production. The expression and role of SLAM in human infectious disease were investigated using leprosy as a model. We found that SLAM mRNA and protein were more strongly expressed in skin lesions of tuberculoid patients, those with measurable CMI to the pathogen, Mycobacterium leprae, compared with lepromatous patients, who have weak CMI against M. leprae. Peripheral blood T cells from tuberculoid patients showed a striking increase in the level of SLAM expression after stimulation with M. leprae, whereas the expression of SLAM on T cells from lepromatous patients show little change by M. leprae stimulation. Engagement of SLAM by an agonistic mAb up-regulated IFN-gamma production from tuberculoid patients and slightly increased the levels of IFN-gamma in lepromatous patients. In addition, IFN-gamma augmented SLAM expression on M. leprae-stimulated peripheral blood T cells from leprosy patients. Signaling through SLAM after IFN-gamma treatment of Ag-stimulated cells enhanced IFN-gamma production in lepromatous patients to the levels of tuberculoid patients. Our data suggest that the local release of IFN-gamma by M. leprae-activated T cells in tuberculoid leprosy lesions leads to up-regulation of SLAM expression. Ligation of SLAM augments IFN-gamma production in the local microenvironment, creating a positive feedback loop. Failure of T cells from lepromatous leprosy patients to produce IFN-gamma in response to M. leprae contributes to reduced expression of SLAM. Therefore, the activation of SLAM may promote the cell-mediated immune response to intracellular bacterial pathogens.     

Dinitrogen fixation and infection of grass leaves byPseudomonas rubrisubalbicans andHerbaspirillum seropedicae

Bacteria causing mottled stripe disease in sugar cane, known asPseudomonas rubrisubalbicans, were shown to be able to fix molecular N₂ and to grow on it. The root associated diazotroph known asHerbaspirillum seropedicae, after artificial inoculation caused mottled stripe disease symptoms on sorghum and Napier grass but not on sugar cane. Both bacteria could be reisolated from leaves even 60 days after. Sugar cane leaves contained large numbers of these bacteria even in the uninoculated controls. Additional physiological characteristics of six strains ofP. rubrisubalbicans were compared with those of twoH. seropedicae strains and were shown to be very similar.     

Effect of Zinc Sulfate Fortificant on Iron Absorption from Low Extraction Wheat Flour Co-Fortified with Ferrous Sulfate

The co-fortification of wheat flour with iron (Fe) and zinc (Zn) is a strategy used to prevent these deficiencies in the population. Given that Zn could interact negatively with Fe, the objective was to assess the effect of Zn on Fe absorption from bread prepared with wheat flour fortified with Fe and graded levels of Zn fortificant. Twelve women aged 30–43 years, with contraception and a negative pregnancy test, participated in the study. They received on four different days, after an overnight fast, 100 g of bread made with wheat flour (70 % extraction) fortified with 30 mg Fe/kg as ferrous sulfate (A) or prepared with the same Fe-fortified flour but with graded levels of Zn, as zinc sulfate: 30 mg/kg (B), 60 mg/kg (C), or 90 mg/kg (D). Fe radioisotopes (⁵⁹Fe and ⁵⁵Fe) of high specific activity were used as tracers and Fe absorption iron was measured by the incorporation of radioactive Fe into erythrocytes. Results: The geometric mean and range of ±1 SD of Fe absorption were: A?=?19.8 % (10.5–37.2 %), B?=?18.5 % (10.2–33.4 %), C?=?17.7 % (7.7–38.7 %), and D?=?11.2 % (6.2–20.3 %), respectively; ANOVA for repeated measures F?=?5.14, p?<?0.01 (Scheffè’s post hoc test: A vs D and B vs D, p?<?0.05). We can conclude that Fe is well absorbed from low extraction flour fortified with 30 mg/kg of Fe, as ferrous sulfate, and up to 60 mg/kg of Zn, as Zn sulfate. A statistically significant reduction of Fe absorption was observed at a Zn fortification level of 90 mg Zn/kg.     

Antibiotic production by Pseudomonas reptilivora as a phage conversion

The ability of Pseudomonas reptilivora to produce three broad-spectrum antimicrobial substances is easily lost when bacteria are subcultured. The study of the antibiotic production under defined culture conditions has shown that the biosynthesis of these substances depends upon the presence of a temperature-sensitive temperate phage. Antibiotic production is lost after phage induction.