Development of systemic and mucosal immune responses against gut microbiota in early life and implications for the onset of allergies.

The early microbial colonization of human mucosal surfaces is essential for the development of the host immune system. Already during pregnancy, the unborn child is prepared for the postnatal influx of commensals and pathogens via maternal antibodies, and after birth this protection is continued with antibodies in breast milk. During this critical window of time, which extends from pregnancy to the first year of life, each encounter with a microorganism can influence children's immune response and can have a lifelong impact on their life. For example, there are numerous links between the development of allergies and an altered gut microbiome. However, the exact mechanisms behind microbial influences, also extending to how viruses influence host-microbe interactions, are incompletely understood. In this review, we address the impact of infants' first microbial encounters, how the immune system develops to interact with gut microbiota, and summarize how an altered immune response could be implied in allergies.

Maternal Overweight and Obesity and Their Effect on the Growth of the Newborn During the First Six Months of Life.

INTRODUCTION:  Maternal overweight and obesity during pregnancy have been shown to have multiple negative effects on the mother's health, which can even affect the infant's growth by increasing weight gain and altering various indicators, such as weight for age, length for age and weight for length. While breast milk on the other hand reduces these risks, and it's the best and most complete food for the newborn. It's a dynamic fluid capable of being modified to meet the needs of each stage of the newborn, but despite this capacity and the fact that maternal body mass index can have an impact on its components, through complex biological mechanisms, it manages to reduce the negative effects accumulated during pregnancy and even promotes a healthy state in the baby. In a country like Mexico, where overweight and obesity affect a large part of the population, it is important to study their causes and which could be the effect of this increased maternal overweight during pregnancy and lactation on newborns. OBJECTIVE: Identify the alterations associated with increased maternal body mass index during pregnancy and breastfeeding on mothers' health and their possible effect on the growth of the newborn during the first six months of life. MATERIAL AND METHODS: This was a prospective cohort study. Forty-two healthy binomials (mother and child), without problems during delivery and without serious illnesses during the breastfeeding period, were included. Maternal body mass index at the beginning of pregnancy allowed us to create two comparison groups between mothers: one with adequate weight, another with overweight or obesity. Follow-up was carried out once a month during the first six months of life, evaluating the somatometric development of mothers and children. All mothers completed the six-month period of exclusive breastfeeding. RESULTS:  There were differences between both groups of women. The one that included overweight and obese women compared to the group of women with adequate weight had a higher number of pregnancies, abortions, plasma glucose levels in the third trimester of pregnancy, and a lower number of prenatal control visits and plasma platelet levels (all with p<0.05). Regarding the baby's growth, there was a difference between the weight for length classification at 60-, 120-, 150- and 180-day follow-ups. The group to which the mother was assigned with respect to her body mass index at the beginning of pregnancy (adequate weight group and overweight/obese group) was the only factor associated with the risk of the baby being overweight according to weight for length indicator at the 180-day follow-up, with an OR = 5.2 (95%CI 1.02-26.59). CONCLUSIONS: Maternal overweight and obesity during pregnancy have a negative effect on the mother's health and baby's weight gain in its weight-for-length classification during the first six months of life. Although breastfeeding has been shown to have a positive effect on the growth of the baby, exposure to a higher maternal body mass index during pregnancy triggers important metabolic alterations that promote the development of diseases. It is important to establish weight control guidelines in women who wish to become pregnant to reduce the negative effects on the mother and offspring.

Passively administered fluoxetine reaches the juvenile brain of FSL rats and reduces antioxidant defences, without altering serotonin turnover.

BACKGROUND: Fluoxetine is present in breast milk, yet it is unclear to what extent it, or its active metabolite, norfluoxetine, reaches the brain of the infant and what the effects of such exposure on neurobiological processes are. We therefore aimed to quantify the concentration of passively administered fluoxetine and norfluoxetine in the whole brains of exposed Flinders sensitive line (FSL) offspring and establish their influence on serotonergic function and redox status. METHODS: Adult FSL dams received fluoxetine (10 mg/kg/day), or placebo for fourteen days, beginning on postpartum day 04. Offspring were passively exposed to fluoxetine until postnatal day 18 and euthanized on postnatal day 22. Whole brain fluoxetine, norfluoxetine, serotonin (5-HT), 5-hydroxyindoleacetic acid (5-HIAA), and reduced (GSH) and oxidized glutathione (GSSG) concentrations were measured via liquid chromatography-mass spectrometry (LC-MS) analysis. RESULTS: Whole-brain serotonin and 5-hydroxyindoleacetic acid concentrations, and serotonin turnover (5-HIAA/5-HT) were comparable between strains. Treatment-naïve FSL rats had lower GSH and higher GSSG whole-brain concentrations, relative to FRL controls, and an overall decreased GSH/GSSG ratio. Passively administered fluoxetine resulted in undetectable whole-brain concentrations, while norfluoxetine averaged 41.28 ± 6.47 ng/g. Serotonin turnover of FSL rats was unaffected by passively administered fluoxetine, while redox status (GSH/GSSG) was decreased. CONCLUSION: Our findings confirm that passively administered fluoxetine reaches the infant brain in the form of norfluoxetine and may manipulate processes of oxidative stress regulation. Further studies into the long-term bio-behavioural effects are however needed to effectively inform breast feeding mothers on the safety of antidepressant-use.

Assessing immune factors in maternal milk and paired infant plasma antibody binding to human rhinoviruses.

Introduction: Before they can produce their own antibodies, newborns are protected from infections by transplacental transfer of maternal IgG antibodies and after birth through breast milk IgA antibodies. Rhinovirus (RV) infections are extremely common in early childhood, and while RV infections often result in only mild upper respiratory illnesses, they can also cause severe lower respiratory illnesses such as bronchiolitis and pneumonia. Methods: We used high-density peptide arrays to profile infant and maternal antibody reactivity to capsid and full proteome sequences of three human RVs - A16, B52, and C11. Results: Numerous plasma IgG and breast milk IgA RV epitopes were identified that localized to regions of the RV capsid surface and interior, and also to several non-structural proteins. While most epitopes were bound by both IgG and IgA, there were several instances where isotype-specific and RV-specific binding were observed. We also profiled 62 unique RV-C protein loop sequences characteristic of this species' capsid VP1 protein. Discussion: Many of the RV-C loop sequences were highly bound by IgG from one-year-old infants, indicating recent or ongoing active infections, or alternatively, a level of cross-reactivity among homologous RV-C sites.

Comparison of prenatal and postnatal exposure to neonicotinoids and their temporal trends in breast milk.

Although the potential effects of neonicotinoids (NEOs) in early life have received considerable attention, data on the exposure of mothers and infants to NEOs are scarce. In this study, four parent NEOs and one metabolite were widely detected in paired maternal serum (MS), umbilical cord serum (UCS) and breast milk (BM) samples, with median total NEO concentrations (ΣNEOs) of 113, 160 and 69 ng/L, respectively. Decreasing trends were observed for N-desmethyl-acetamiprid (30 %/year), acetamiprid (22 %/year) and ΣNEOs (15 %/year) in breast milk between 2014 and 2022, whereas increasing trends were seen for clothianidin (17 %/year) and thiamethoxam (30 %/year). N-desmethyl-acetamiprid was the predominant compound in all matrices. However, the contributions of N-desmethyl-acetamiprid (35 %) and thiamethoxam (36 %) in breast milk were similar in 2022. Moreover, thiamethoxam has become the predominant contributor to the estimated daily intake of ΣNEOs since 2018, with the highest contribution of 71 % in 2022, suggesting the effects of NEOs continue to evolve and more attention should be paid to the new NEOs. Notably, the correlations and ratios of NEOs between paired UCS and MS were more significant and higher than those between paired BM and MS, respectively, indicating that NEO exposure was largely affected by the prenatal period.

Quantification of ADHD medication in biological fluids of pregnant and breastfeeding women with liquid chromatography: a comprehensive review.

Attention Deficit/Hyperactivity Disorder (ADHD) is a neurodevelopmental disorder that has long been considered a concern only in the pediatric population. However, symptoms often sustain into adulthood and may require medication. For women with ADHD, this also means dealing with the disorder during the reproductive period. Medication safety during pregnancy and breastfeeding is a critical concern, and the potential transfer of ADHD medication to infants remains a topic of scientific interest. The quantification of ADHD medications in both maternal blood and breast milk are vital for understanding their pharmacokinetics and potential exposure risks for (nursing) infants. This review aims (1) to compile and critically assess existing research on the transfer of ADHD medications into breast milk and the potential implications for nursing infants and (2) to provide a comprehensive overview and discussion of the literature regarding the quantification of methylphenidate, amphetamine, atomoxetine, viloxazine, guanfacine, clonidine and bupropion in the blood, urine, oral fluid, and breast milk with liquid chromatography. A literature search was conducted using PubMed, Scopus, and Web of Science, to identify relevant articles published from January 2014 up to December 2023. We illustrate the lack of methods to simultaneously monitor multiple ADHD medications as well as the lack of developed methods for breast milk. Finally, we highlight the need for continued research to refine our understanding of medication transfer into breast milk and potential risks, and to develop clinical guidelines to support mothers with ADHD in making informed choices regarding medication use during pregnancy and lactation.

Diet at birth is critical for healthy growth, independent of effects on the gut microbiota.

BACKGROUND: Colostrum is the first milk for a newborn. Its high content in microbiota shaping compounds and its intake at the time of gut microbiota seeding suggests colostrum may be critical in the establishment of a healthy microbiota. There is also accumulating evidence on the importance of the gut microbiota for healthy growth. Here, we aimed to investigate the contribution of colostrum, and colostrum-induced microbiota to growth promotion. Addressing this question is highly significant because (1) globally, less than half of the newborns are fully colostrum fed (2) the evidence for the importance of the microbiota for the prevention of undernutrition has only been demonstrated in juvenile or adult pre-clinical models while stunting already starts before weaning. RESULTS: To address the importance of diet at birth in growth failure, we developed a unique mouse model in which neonates are breastfed by mothers at an advanced stage of lactation who no longer provide colostrum. Feeding newborn mice with mature milk instead of colostrum resulted in significant growth retardation associated with the biological features of chronic undernutrition, such as low leptin levels, dyslipidemia, systemic inflammation, and growth hormone resistance. We next investigated the role of colostrum in microbiota shaping. At the end of the lactation period, we found a major difference in gut microbiota alpha diversity, beta diversity, and taxa distribution in control and colostrum-deprived mice. To determine the causal relationship between changes in microbiota and growth trajectories, we repeated our experiment in germ-free mice. The beneficial effect of colostrum on growth remained in the absence of microbiota. CONCLUSION: Our data suggest that colostrum may play an important role in the prevention of growth failure. They highlight that the interplay between neonatal gut microbiome assembly and diet may not be as crucial for growth control in the developing newborn as described in young adults. This opens a paradigm shift that will foster research for colostrum's bioactives that may exert a similar effect to microbiota-derived ligands in promoting growth and lead to new avenues of translational research for newborn-tailored prevention of stunting. Video Abstract.

Trends and practices of weaning in infants across India: A comprehensive review.

Weaning is a critical phase in an infant's life, during which there is a transition from exclusive breastfeeding or formula feeding to consuming solid foods. Weaning is a critical step in determining a child's nutritional status, growth, and general health. India is a multiethnic and culturally diverse nation and has a variety of weaning practices that are affected by local customs, religious beliefs, and socioeconomic concerns. Malnutrition brought on by inadequate weaning methods used in infancy and early childhood may have an impact on cognitive, motor and social, development and productivity of the child, more importantly manifesting in later ages. Weaning customs in India have a long history of being ingrained in both family and cultural traditions. The variety of Indian cuisine is reflected in the meals that are offered to the infant during weaning. Homemade food commonly prepared like mashed fruits and vegetables, lentil soups, and rice porridge are the most popular. However, the inclination by parents toward professionally produced infant foods and formulas has increased because of urbanization and globalization; there have been observable changes in weaning practices over the past few decades because of changing lifestyles and easier access. These foods are frequently thought of as more convenient but may not be as nutrient-dense as homemade alternatives. Not following the medically recommended mandate of an exclusive diet of mother's breast milk to the infant, many parents often begin introducing complementary foods as early as four months. Still most concerningly also the timing of weaning commencement varies significantly across areas and communities. Overall, this review offers valuable insights into the current trends and practices of weaning in infants across India, underscoring the importance of culturally sensitive and informed strategies to ensure the well-being of the nation's youngest population.

Screening for compounds with bioaccumulation potential in breast milk using their retention behavior in two-dimensional gas chromatography.

Discovery of emerging pollutants in breast milk will be helpful for understanding the hazards to human health. However, it is difficult to identify key compounds among thousands present in complex samples. In this study, a method for screening compounds with bioaccumulation potential was developed. The method can decrease the number of compounds needing structural identification because the partitioning properties of bioaccumulative compounds can be mapped onto GC×GC chromatograms through their retention behaviors. Twenty pooled samples from seven provinces in China were analyzed. 1,286 compounds with bioaccumulation potential were selected from over 3,000 compounds. Sixty-two compounds, including aromatic compounds, phthalates, and phenolics etc., were identified with a high level of confidence and then quantified. Among them, twenty-seven compounds were found for the first time in breast milk. Three phthalate plasticizers and two phenolic antioxidants were found in significantly higher concentrations than other compounds. A toxicological priority index approach was applied to prioritize the compounds considering their concentrations, detection frequencies and eight toxic effects. The prioritization indicated that 13 compounds, including bis(2-ethylhexyl) phthalate, dibutyl phthalate, 1,3-di-tert-butylbenzene, phenanthrene, 2,6-di-tert-butyl-1,4-benzoquinone, 2,4-di-tert-butylphenol, and others, showed higher health risks. Meanwhile, some compounds with high risk for a particular toxic effect, such as benzothiazole and geranylacetone, were still noteworthy. This study is important for assessing the risks of human exposure to organic compounds.

Transfer of celiac disease-associated immunogenic gluten peptides in breast milk: variability in kinetics of secretion.

Background: Exposure to antigens is crucial for child immune system development, aiding disease prevention and promoting infant health. Some common food antigen proteins are found in human breast milk. However, it is unclear whether gluten antigens linked to celiac disease (CD) are transmitted through breast milk, potentially impacting the development of the infant's immune system. Objective: This study aimed to analyze the passage of gluten immunogenic peptides (GIP) into human breast milk. We evaluated the dynamics of GIP secretion after lactating mothers adopted a controlled gluten-rich diet. Methods: We prospectively enrolled 96 non-CD and 23 CD lactating mothers, assessing total proteins and casein in breast milk, and GIP levels in breast milk and urine. Subsequently, a longitudinal study was conducted in a subgroup of 12 non-CD lactating mothers who adopted a controlled gluten-rich diet. GIP levels in breast milk and urine samples were assayed by multiple sample collections over 96 hours. Results: Analysis of a single sample revealed that 24% of non-CD lactating mothers on a regular unrestricted diet tested positive for GIP in breast milk, and 90% tested positive in urine, with significantly lower concentrations in breast milk. Nevertheless, on a controlled gluten-rich diet and the collection of multiple samples, GIP were detected in 75% and 100% of non-CD participants in breast milk and urine, respectively. The transfer dynamics in breast milk samples were long-enduring and GIP secretion persisted from 0 to 72 h. In contrast, GIP secretion in urine samples was limited to the first 24 h, with inter-individual variations. In the cohort of CD mothers, 82.6% and 87% tested negative for GIP in breast milk and urine, respectively. Conclusions: This study definitively established the presence of GIP in breast milk, with substantial inter-individual variations in secretion dynamics. Our findings provide insights into distinct GIP kinetics observed in sequentially collected breast milk and urine samples, suggesting differential gluten metabolism patterns depending on the organ or system involved. Future research is essential to understand whether GIP functions as sensitizing or tolerogenic agents in the immune system of breastfed infants.

Relationship between Receipt of the Samples of Breast Milk Substitutes in Hospitals and Breastfeeding Practice in Japan.

Objective: This study estimated the percentage of mothers who received samples of breast milk substitutes at medical facilities and examined the relationship between receipt of the samples and breastfeeding practices in Japan. Methods: We used the data from the "The Japan COVID-19 and Society Internet Survey (JACSIS)" conducted in 2021. Two groups of mothers were analyzed: mothers 0-5 months postpartum (n = 1,412) and mothers 5-12 months postpartum (n = 2,045). Logistic regression analysis was conducted with the practice of exclusive breastfeeding as the dependent variable and the receipt of the sample as the explanatory variable. Exclusive breastfeeding was defined in different ways for each group: "exclusive breastfeeding under five months" as measured by 24-hour recall for mothers 0-5 months postpartum, and "exclusive breastfeeding for the first five months" as defined by asking mothers 5-12 months postpartum when they first fed infant formula or baby food and when they finished breastfeeding. Results: The proportion of mothers who received the samples was 82.4%. We found that mothers who received the samples were found to be less likely to continue "exclusive breastfeeding under five months" (odds ratio: 0.71, 95% confidence interval [CI]: 0.51-0.98). In addition, a similar trend was found in a subsample analysis restricted to mothers who intended to breastfeed during pregnancy (odds ratio: 0.62, 95% CI: 0.40-0.94). Conclusions: This study showed that more than 80% of mothers had received the samples of breast milk substitutes, and that receipt of the samples decreased the probability of their practicing exclusive breastfeeding. Regulating distribution of the samples at medical facilities is necessary to prevent interruptions of exclusive breastfeeding.

Biological clock and circadian rhythm of breast milk composition.

Breast milk provides numerous benefits for both the baby and the mother, making it a unique and valuable food. The World Health Organization and the United Nations International Children's Emergency Found (UNICEF) state that exclusive breastfeeding in the first six months of life is an important strategy for reducing mortality and morbidity in infants. The circadian rhythm formation, which starts in the mother's womb, continues after the baby is born. Breast milk plays an active role in regulating the baby's circadian rhythm through the hormones, basic immune factors and bioactive components it contains, as well as meeting almost all nutritional elements for babies. Since the neural control mechanisms in the newborn are not yet fully developed, breast milk undertakes the task of helping the biological rhythms in the regulation of the infant's sleep-wake cycles, thanks to the circadian rhythm of some elements in its composition. There are studies showing that breast milk contains high levels of cortisol and amino acids that promote activity during the day, while night milk has high levels of melatonin and tryptophan, and micronutrients vary throughout the day. A better understanding of the circadian rhythm displayed by the elements in the composition of breast milk is important for improving maternal and infant health. Since there are many factors affecting the composition of breast milk, it is recommended that breast milk studies should be done on a country or regional basis, and breastfeeding policies can be developed as a result of the results to be obtained.

Smoking-induced suppression of ß-casein in milk is associated with an increase in miR-210-5p expression in mammary epithelia.

Smoking during lactation harmfully affects the amount and constituents of breast milk. Infants who consume breast milk containing miR-210-5p may have a higher risk of brain-related diseases. We investigated whether smoking during lactation decreases ß-casein concentrations in milk and whether miR-210-5p expression is involved in smoking-induced ß-casein suppression. During lactation, maternal CD1 mice were exposed to cigarette smoke (1.7 mg of tar and 14 mg of nicotine) in a smoke chamber for 1 h twice/day for five consecutive days. Control mice were placed in an air-filled chamber equivalent in size to the smoke chamber, with maternal separation times identical to those of the smoked mice. Maternal exposure to smoke during lactation significantly decreased ß-casein expression in the mammary epithelia of smoked mice compared to that of the control mice. Signal transducer and activator transcription 5 (STAT5) and phosphorylated STAT5 (pSTAT5) are transcription factors involved in ß-casein expression. In the mammary epithelia of smoked mice, the pSTAT5 and STAT5 levels were significantly lower, and miR-210-5p expression was significantly higher than that of the control mice. The ß-casein, pSTAT5, and STAT5 protein levels of miR-210-5p mimic-transfected human mammary epithelial MCF-12A cells were significantly lower than those of control siRNA-transfected cells. These results indicate that smoke exposure led to an increase in miR-210-5p expression in mammary epithelium and a decrease in pSTAT5 and ß-casein protein levels through the inhibition of STAT5 expression. Moreover, nicotine treatment decreased ß-casein protein levels and increased miR-210-5p expression in non-malignant human mammary epithelial MCF-12A cells in a concentration-dependent manner, demonstrating that nicotine significantly affects the ß-casein and miR-210-5p levels of breast milk. These results highlight the adverse effects of smoking on breast milk, providing essential information for healthcare professionals and general citizens.

The relationship between mothers' body composition and anthropometric characteristics of baby and breast milk nutrient content: A cross-sectional study.

BACKGROUND: The composition and amount of breast milk is affected by factors such as the duration and frequency of breastfeeding, the time between two breastfeeding sessions, the effectiveness of breastfeeding, breastfeeding technique, genetic characteristics of the mother and diet. Breast milk macronutrients are provided by milk synthesized in lactocytes, mother's diet and maternal stores. RESEARCH AIM: This study was conducted to investigate the relationship between the body composition of mothers and the anthropometric characteristics of the baby and the nutritional content of breast milk. METHOD: The descriptive study was conducted between March and November 2023 in a hospital in a low socioeconomic neighbourhood in Turkey. The study sample consisted of 96 mothers and ibabies. Anthropometric measurements of mothers and babies and the nutrient content of breast milk were evaluated on the first postpartum day, Days 5 and 15. Breast milk macronutrient content was analyzed by Miris milk analyzer and body composition of mothers was analyzed by TANITA BC 730. RESULTS: From the weight and body composition of the mothers in the study group; a positive correlation was found between body fat, muscle and water ratio, and breast milk carnonhydrate and protein (p < 0.05). There was no correlation between the gestational age of the baby and the content of breast milk (p > 0.05). A positive correlation was found between the weight and height of the babies and the macronutrients of breast milk (p < 0.05). CONCLUSION: As the weight of mothers increases, breast milk protein and carbohydrate levels increase. As breast milk macronutrients increase, babies' weight and height increase.

A rapid review of motives and barriers for living substance of human origin donation and an extended typology.

Our objective is to review motives and barriers for non-reproductive, living substance of human origin (SoHO) donation, and to extend existing typologies beyond blood. The expansion of SoHO collection is currently unmatched by increased living donors. Thus, there is a critical need to understand how to effectively recruit and retain donors to ensure a sustainable supply of SoHO. We undertook a rapid review and narrative synthesis of published, peer-reviewed literature reporting on motives and/or barriers for living SoHO donation (whole-blood, blood products [2009-2023], bone marrow/stem cells, cord blood, organ, human breast milk, intestinal microbiota [2000-2023]). Results were interpreted through directed qualitative content analysis using an extended typology of motives/barriers largely drawn from blood donation research, and subsequently refined based on results to be inclusive of other SoHO. 234 articles with 237 studies met review criteria. Most were quantitative (74.3%), conducted in Western countries (63.8%), focused on blood donation (64.2%), reported motives and barriers (51.9%) and did not examine differences by donor characteristics or history (74%). We present a revised typology inclusive of motives/barriers for donation of substances beyond blood. This shows while broader motives and barriers are shared across substances donated, there are critical differences at the subcategory level that may account for heterogeneity in results of prior interventions. The nuances in how broad categories of motives and barriers manifest across different SoHO are critical for blood collection agencies to consider as they attempt to expand collection of products beyond whole-blood, plasma, and platelets. WHAT IS KNOWN ABOUT THE TOPIC?: Blood collection agencies (BCAs) continue to expand SoHO product collection beyond whole-blood, plasma, and platelets. The demand for SoHO is currently unmatched by increased living donors. The need to understand how to recruit new and retain existing living donors to ensure a sustainable supply of SoHO remains critical. However, there is no available synthesis of the factors, such as motives/facilitators and barriers/deterrents, to inform our understanding. WHAT IS NEW?: Comprehensively reviewed evidence for motives and barriers of willing/actual donors and nondonors across all types of non-reproductive living SoHO donation. Explored variations in motives and barriers based on substance, donor history and demographic differences (gender, age, ethnicity or culture). Extended typology of motives and barriers inclusive of all non-reproductive living SoHO, beyond solely whole-blood and blood products. Identified that while there are commonalities in the overarching motive and barrier categories across substances (e.g., prosocial motivation, low self-efficacy), within these broader constructs there are differences at the subcategory level (e.g., low-self efficacy was about eligibility, lifestyle barriers, or lack/loss of financial or material resources depending on the substance donated) that are crucial for development of future interventions and for BCAs to consider as they expand SoHO product collection. Highlighted the continued focus on motives and barriers for whole-blood and blood product donation to the exclusion of other, particularly newer, SoHO; lack of qualitative work for newer SoHO; and lack of consideration of differences based on donor characteristics (especially ethnicity/culture) and donor history, which limits our understanding. WHAT ARE THE KEY QUESTIONS FOR FUTURE WORK ON THE TOPIC?: What are the motives and barriers (in both qualitative and quantitative studies) for donation of newer SoHO such as stem cells, cord blood, human milk, and intestinal microbiota? Are there differences in motives and barriers within and across SoHO that are informed by individual and contextual-level factors? How can we develop interventions that respond to the nuances of motives and barriers present across different forms of SoHO that are effective in encouraging new and maintaining continuing donors?

Investigating the Dietary Impact on Trans-Vaccenic Acid (Trans-C18:1 n-7) and Other Beneficial Fatty Acids in Breast Milk and Infant Formulas.

Maternal diet plays a significant role in the fatty acid composition of breast milk. Dietary products such as milk and meat are the primary sources of natural TFAs for humans. These peculiar fatty acids hold nutritional significance as they not only lack the detrimental effects of industrially produced trans fats on the endothelium characteristic, but they also exhibit anti-inflammatory properties. The relationship between the presence of eight fatty acids in breast milk (including natural TFAs trans-vaccenic and conjugated linoleic acid) and the maternal diet has been explored, and their abundance has been compared to that of infant formulas. Two cohorts of lactating women, originating from a Spanish region, participated in this study; they adhered to the Southern European Atlantic diet or the Atlantic diet. While the consumption of conventional meat or dairy products does not seem to increase the abundance of TFAs in breast milk, trans-vaccenic and oleic acid are among the most distinctive features of breast milk fat in mothers consuming naturally improved dairy products with an improved fatty acid profile. The most significant differences between natural breastfeeding and formula feeding lie in natural TFAs, since formulas are notably deficient in natural TFAs while being overfortified in alpha-linolenic acid in comparison to breast milk. We suggest an improvement in the formulation of these products through using cow's milk with an optimal fatty acid profile that better mimics the fatty acid composition found in human milk.

The Assessment of Iodine Concentrations in Colostrum and Breast Milk Using ICP-MS: The Impact of Delivery Type, Thyroid Function and Gestational Diabetes-A Pilot Study.

Considering the spectrum of benefits of breast milk feeding, determining the essential components of an infant's only food-mother's milk-seems justified, especially in the case of those whose deficiency (e.g., iodine) may result in developmental disorders. The main aim of this study was the determination of the total iodine content of breast milk (including colostrum and mature milk). A secondary objective was to assess the influence of factors such as the type of delivery, hypothyroidism, gestational diabetes or the stage of lactation on this parameter. The study materials were colostrum and milk after 1 (n = 14), 2 and 3 months (n = 8) of lactation with a range of iodine concentrations (µg/L): 195-1648 and 170-842, 174-650 and 273-751, respectively. Iodine was determined using the inductively coupled plasma mass spectrometry (ICP-MS). Multivariate statistical analysis revealed, e.g., that delivery by caesarean section or dose of L-thyroxine taken by women to normalise thyroid hormones, had a significant effect on iodine concentrations in breast milk. Further research aimed at assessing the quality of breast milk should also include determining the factors influencing it.

Detection of Microplastics in Human Breast Milk and Its Association with Changes in Human Milk Bacterial Microbiota.

Background: Presently, there is increasing public consciousness regarding the contamination and detection of microplastics (MPs) within the human body, and studies on the detection and characterization of MPs in human breast milk are limited. Objectives: This study aims to investigate the prevalence and characteristics of MPs found in human breast milk and examine the relationship between maternal hygiene practices, complications that may arise during breastfeeding, and the composition of the bacterial microbiota. Methods: Postpartum breast milk was analyzed for MPs using Raman micro-spectroscopy. The relationship between MP detection, maternal hygiene, breastfeeding complications, and bacterial microbiota was examined. In order to identify correlations and differences between groups that had detected and non-detected MPs, statistical analyses were performed, which involved demographic comparisons and correlation network analysis. Results: The mean age of the 59 postpartum women was 28.13 years. We found MPs in 38.98% of breast milk samples (23 of 59), exhibiting diverse morphological and chemical characteristics. Most MP polymers were polypropylene, polyethylene, polystyrene, and polyvinyl chloride. Maternal hygiene and breastfeeding complications differed between the MPs-detected and non-detected groups. Maternal behaviors may influence the presence of microplastics in breast milk, which were associated with these differences. Bacterial microbiota analysis revealed significant taxonomic differences between the MPs-detected and non-detected groups. Staphylococcus and Streptococcus dominated the MPs-detected group, while Enterobacter, Escherichia, Pseudomonas, and Acinetobacter dominated the non-detected group. The MPs-detected group had a more even bacterial distribution, especially Bacteroides. Conclusions: This study found MPs in 38.98% of breast milk samples using Raman micro-spectrometry, with PP, PE, and PVC being the most common. Significant differences in maternal hygiene and breastfeeding complications were found between the groups with and without MPs. Breast milk microbiota may be linked to MP detection. Further study should be conducted to identify the possible maternal-child health.

Factors Influencing Breast Milk Antibody Titers during the Coronavirus Disease 2019 Pandemic: An Observational Study.

The COVID-19 pandemic has highlighted the role of breastfeeding in providing passive immunity to infants via specific anti-SARS-CoV-2 antibodies in breast milk. We aimed to quantify these antibodies across different lactation stages and identify influencing factors. This prospective study involved mother-child dyads from Innsbruck University Hospital, Austria, with a positive maternal SARS-CoV-2 test during pregnancy or peripartum between 2020 and 2023. We collected breast milk samples at various lactation stages and analyzed anti-Spike S1 receptor-binding domain (S1RBD) immunoglobulins (Ig). Maternal and neonatal data were obtained from interviews and medical records. This study included 140 mothers and 144 neonates. Anti-S1RBD-IgA (72.0%), -IgG (86.0%), and -IgM (41.7%) were highly present in colostrum and decreased as milk matured. Mothers with natural infection and vaccination exhibited higher anti-S1RBD-IgA and -IgG titers in all milk stages. Mothers with moderate to severe infections had higher concentrations of anti-S1RBD-IgA and -IgG in transitional milk and higher anti-S1RBD-IgA and -IgM in mature milk compared to those with mild or asymptomatic infections. Variations in antibody responses were also observed with preterm birth and across different virus waves. This study demonstrates the dynamic nature of breast milk Ig and underscores the importance of breastfeeding during a pandemic.