Bifidobacterium Species Colonization in Infancy: A Global Cross-Sectional Comparison by Population History of Breastfeeding

Bifidobacterium species are beneficial and dominant members of the breastfed infant gut microbiome; however, their health benefits are partially species-dependent. Here, we characterize the species and subspecies of Bifidobacterium in breastfed infants around the world to consider the potential impact of a historic dietary shift on the disappearance of B. longum subsp. infantis in some populations. Across populations, three distinct patterns of Bifidobacterium colonization emerged: (1) The dominance of Bifidobacterium longum subspecies infantis, (2) prevalent Bifidobacterium of multiple species, and (3) the frequent absence of any Bifidobacterium. These patterns appear related to a country’s history of breastfeeding, with infants in countries with historically high rates of long-duration breastfeeding more likely to be colonized by B. longum subspecies infantis compared with infants in countries with histories of shorter-duration breastfeeding. In addition, the timing of infant colonization with B. longum subsp. infantis is consistent with horizontal transmission of this subspecies, rather than the vertical transmission previously reported for other Bifidobacterium species. These findings highlight the need to consider historical and cultural influences on the prevalence of gut commensals and the need to understand epidemiological transmission patterns of Bifidobacterium and other major commensals.     

Poly(vinyl alcohol)/Plant Extracts Films: Preparation,Surface Characterization and Antibacterial Studies against Gram Positive and Gram Negative Bacteria

In this study, we aim to obtain biomaterials with antibacterial properties by combining poly(vinyl alcohol) with the extracts obtained from various selected plants from Romania. Natural herbal extracts of freshly picked flowers of the lavender plant (Lavandula angustifolia) and leaves of the peppermint plant (Mentha piperita), hemp plant (Cannabis sativa L.), verbena plant (Verbena officinalis) and sage plant (Salvia officinalis folium) were selected after an intensive analyzing of diverse medicinal plants often used as antibacterial and healing agents from the country flora. The plant extracts were characterized by different methods such as totals of phenols and flavonoids content and UV-is spectroscopy. The highest amounts of the total phenolic and flavonoid contents, respectively, were recorded for Salvia officinalis. Moreover, the obtained films of poly(vinyl alcohol) (PVA) loaded with plant extracts were studied concerning the surface properties and their antibacterial or cytotoxicity activity. The Attenuated Total Reflection Fourier Transform Infrared analysis described the successfully incorporation of each plant extract in the poly(vinyl alcohol) matrix, while the profilometry demonstrated the enhanced surface properties. The results showed that the plant extracts conferred significant antibacterial effects to films toward Staphylococcus aureus and Escherichia coli and are not toxic against fibroblastic cells from the rabbit.     

Mild Choline Deficiency and MTHFD1 Synthetase Deficiency Interact to Increase Incidence of Developmental Delays and Defects in Mice

Folate and choline are interconnected metabolically. The MTHFD1 R653Q SNP is a risk factor for birth defects and there are concerns that choline deficiency may interact with this SNP and exacerbate health risks. 80–90% of women do not meet the Adequate Intake (AI) for choline. The objective of this study was to assess the effects of choline deficiency on maternal one-carbon metabolism and reproductive outcomes in the MTHFD1-synthetase deficient mouse (Mthfd1S), a model for MTHFD1 R653Q. Mthfd1S^+/+ and Mthfd1S^+/− females were fed control (CD) or choline-deficient diets (ChDD; 1/3 the amount of choline) before mating and during pregnancy. Embryos were evaluated for delays and defects at 10.5 days gestation. Choline metabolites were measured in the maternal liver, and total folate measured in maternal plasma and liver. ChDD significantly decreased choline, betaine, phosphocholine, and dimethylglycine in maternal liver (p < 0.05, ANOVA), and altered phosphatidylcholine metabolism. Maternal and embryonic genotype, and diet-genotype interactions had significant effects on defect incidence. Mild choline deficiency and Mthfd1S^+/− genotype alter maternal one-carbon metabolism and increase incidence of developmental defects. Further study is required to determine if low choline intakes contribute to developmental defects in humans, particularly in 653QQ women.     

Effects of eating behavior on mood: A review of the literature

The literature focusing on the use of food as a regulator of a negative mood state is reviewed. This literature reveals that individuals experiencing a negative mood state arising from disorders ranging from tobacco withdrawal to premenstrual symptoms make use of carbohydrate ingestion, especially simple carbohydrates, to provide a temporary lifting of mood. However, other evidence suggests that some individuals may obtain a more permanent control of their negative mood state by eliminating simple carbohydrates from their diet. While the literature is consistent in demonstrating that carbohydrate consumption can alter a negative mood state, the underlying mechanism mediating this relationship is unknown. © 1993 by John Wiley & Sons, Inc.     

Early structural brain development in infants exposed to HIV and antiretroviral therapy in utero in a South African birth cohort

IntroductionThere is a growing population of children who are HIV‐exposed and uninfected (HEU) with the successful expansion of antiretroviral therapy (ART) use in pregnancy. Children who are HEU are at risk of delayed neurodevelopment; however, there is limited research on early brain growth and maturation. We aimed to investigate the effects of in utero exposure to HIV/ART on brain structure of infants who are HEU compared to HIV‐unexposed (HU).MethodsMagnetic resonance imaging using a T2‐weighted sequence was undertaken in a subgroup of infants aged 2–6 weeks enrolled in the Drakenstein Child Health Study birth cohort, South Africa, between 2012 and 2015. Mother–child pairs received antenatal and postnatal HIV testing and ART per local guidelines. We compared subcortical and total grey matter volumes between HEU and HU groups using multivariable linear regression adjusting for infant age, sex, intracranial volume and socio‐economic variables. We further assessed associations between brain volumes with maternal CD4 cell count and ART exposure.ResultsOne hundred forty‐six infants (40 HEU; 106 HU) with high‐resolution images were included in this analysis (mean age 3 weeks; 50.7% male). All infants who were HEU were exposed to ART (88% maternal triple ART). Infants who were HEU had smaller caudate volumes bilaterally (5.4% reduction, p < 0.05) compared to HU infants. There were no group differences in other subcortical volumes (all p > 0.2). Total grey matter volume was also reduced in infants who were HEU (2.1% reduction, p < 0.05). Exploratory analyses showed that low maternal CD4 cell count (<350 cells/mm³) was associated with decreased infant grey matter volumes. There was no relationship between timing of ART exposure and grey matter volumes.ConclusionsLower caudate and total grey matter volumes were found in infants who were HEU compared to HU in the first weeks of life, and maternal immunosuppression was associated with reduced volumes. These findings suggest that antenatal HIV exposure may impact early structural brain development and improved antenatal HIV management may have the potential to optimize neurodevelopmental outcomes of children who are HEU.     

From the Cover: Association of improved air quality with lower dementia risk in older women

Late-life ambient air pollution is a risk factor for brain aging, but it remains unknown if improved air quality (AQ) lowers dementia risk. We studied a geographically diverse cohort of older women dementia free at baseline in 2008 to 2012 (n = 2,239, aged 74 to 92). Incident dementia was centrally adjudicated annually. Yearly mean concentrations of fine particulate matter (PM_2.5) and nitrogen dioxide (NO₂) were estimated using regionalized national universal kriging models and averaged over the 3-y period before baseline (recent exposure) and 10 y earlier (remote exposure). Reduction from remote to recent exposures was used as the indicator of improved AQ. Cox proportional hazard ratios (HRs) for dementia risk associated with AQ measures were estimated, adjusting for sociodemographic, lifestyle, and clinical characteristics. We identified 398 dementia cases during follow up (median = 6.1 y). PM_2.5 and NO₂ reduced significantly over the 10 y before baseline. Larger AQ improvement was associated with reduced dementia risks (HR_PM2.5 0.80 per 1.78 μg/m³, 95% CI 0.71–0.91; HR_NO2 0.80 per 3.91 parts per billion, 95% CI 0.71–0.90), equivalent to the lower risk observed in women 2.4 y younger at baseline. Higher PM_2.5 at baseline was associated with higher dementia risk (HR_PM2.5 1.16 per 2.90 μg/m³, 95% CI 0.98–1.38), but the lower dementia risk associated with improved AQ remained after further adjusting for recent exposure. The observed associations did not substantially differ by age, education, geographic region, Apolipoprotein E e4 genotypes, or cardiovascular risk factors. Long-term AQ improvement in late life was associated with lower dementia risk in older women.

Consistent evidence from epidemiologic studies and toxicological experiments has shown that ambient air pollution is an important modifiable risk factor of dementia (1). Several studies have shown an increased risk of dementia associated with late-life exposures to regional fine particulate matter (PM_2.5; with aerodynamic diameter < 2.5 μm) (2–15) and gaseous pollutants (e.g., NO₂; NO_x) (2–4, 11, 12, 15–17) in particular. Over the past 50 y, significant improvements in air quality (AQ) have been observed across the United States because of national policies and strategies aimed at regulating pollution from stationary (power plants; factories) and mobile (vehicles) sources (18). Several US studies have shown that these long-term reductions in air pollution levels are associated with improved lung function (19), decreased bronchitic symptoms (20), lower asthma incidence (21), lengthened life expectancy (22), and reduced mortality (23). However, it remains unclear whether improved AQ also benefits the aging brains.Therefore, we conducted a multiyear study to examine the association between improved AQ and incidence of dementia, which was based on Diagnostic and Statistical Manual of Mental Disorders (Fourth edition) criteria and centrally adjudicated annually (24, 25). We examined data from the Women’s Health Initiative (WHI) Memory Study (WHIMS)—Epidemiology of Cognitive Health Outcomes (WHIMS-ECHO) that included a combined 20 y of data on individual-level outdoor air pollution (1998 to 2012) estimated using regionalized national universal kriging models (26–28) and cognitive function assessed annually (2008 to 2018) in a geographically diverse sample of community-dwelling older women in the United States. We hypothesized that improved AQ over the span of 10 y, as indicated by reductions in PM_2.5 and NO₂ (proxy for traffic pollutants), was associated with lower dementia risk.