Browsing by Subject "microbiome"

Now showing 1 - 6 of 6
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    Bifidobacterium longum Subspecies infantis (B. infantis) in Pediatric Nutrition: Current State of Knowledge
    (MDPI, 2020-05-28) Chichlowski, Maciej; Shah, Neil; Wampler, Jennifer L.; Wu, Steven S.; Vanderhoof, Jon A.; Pediatrics, School of Medicine
    Since originally isolated in 1899, the genus Bifidobacterium has been demonstrated to predominate in the gut microbiota of breastfed infants and to benefit the host by accelerating maturation of the immune response, balancing the immune system to suppress inflammation, improving intestinal barrier function, and increasing acetate production. In particular, Bifidobacterium longum subspecies infantis (B. infantis) is well adapted to the infant gut and has co-evolved with the mother-infant dyad and gut microbiome, in part due to its ability to consume complex carbohydrates found in human milk. B. infantis and its human host have a symbiotic relationship that protects the preterm or term neonate and nourishes a healthy gut microbiota prior to weaning. To provide benefits associated with B. infantis to all infants, a number of commercialized strains have been developed over the past decades. As new ingredients become available, safety and suitability must be assessed in preclinical and clinical studies. Consideration of the full clinical evidence for B. infantis use in pediatric nutrition is critical to better understand its potential impacts on infant health and development. Herein we summarize the recent clinical studies utilizing select strains of commercialized B. infantis.
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    Childhood Respiratory Viral Infections and the Microbiome
    (Elsevier, 2023-10) Kloepfer, Kirsten M.; Kennedy, Joshua L.; Pediatrics, School of Medicine
    The human microbiome associated with the respiratory tract is diverse, heterogeneous, and dynamic. The diversity and complexity of the microbiome and the interactions between microorganisms, host cells, and the host immune system are complex and multifactorial. Furthermore, the lymphatics provide a direct highway, the gut-lung axis, for the gut microbiome to affect outcomes related to respiratory disease and the host immune response. Viral infections in the airways can also alter the presence or absence of bacterial species, which might increase the risks for allergies and asthma. Viruses infect the airway epithelium and interact with the host to promote inflammatory responses that can trigger a wheezing illness. This immune response may alter the host's immune response to microbes and allergens, leading to T2 inflammation. However, exposure to specific bacteria may also tailor the host's response long before the virus has infected the airway. The frequency of viral infections, age at infection, sampling season, geographic location, population differences, and preexisting composition of the microbiota have all been linked to changes in microbiota diversity and stability. This review aims to evaluate the current reported evidence for microbiome interactions and the influences that viral infection may have on respiratory and gut microbiota, affecting respiratory outcomes in children.
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    Fecal Microbiota Transplantation Is Highly Effective in Real-World Practice: Initial Results From the FMT National Registry
    (Elsevier, 2021-01) Kelly, Colleen R.; Yen, Eugene F.; Grinspan, Ari M.; Kahn, Stacy A.; Atreja, Ashish; Lewis, James D.; Moore, Thomas A.; Rubin, David T.; Kim, Alison M.; Serra, Sonya; Nersesova, Yanina; Fredell, Lydia; Hunsicker, Dea; McDonald, Daniel; Knight, Rob; Allegretti, Jessica R.; Pekow, Joel; Absah, Imad; Hsu, Ronald; Vincent, Jennifer; Khanna, Sahil; Tangen, Lyn; Crawford, Carl V.; Mattar, Mark C.; Chen, Lea Ann; Fischer, Monika; Arsenescu, Razvan I.; Feuerstadt, Paul; Goldstein, Jonathan; Kerman, David; Ehrlich, Adam C.; Wu, Gary D.; Laine, Loren; Medicine, School of Medicine
    Background & Aims Fecal microbiota transplantation (FMT) is used commonly for treatment of Clostridioides difficile infections (CDIs), although prospective safety data are limited and real-world FMT practice and outcomes are not well described. The FMT National Registry was designed to assess FMT methods and both safety and effectiveness outcomes from North American FMT providers. Methods Patients undergoing FMT in clinical practices across North America were eligible. Participating investigators enter de-identified data into an online platform, including FMT protocol, baseline patient characteristics, CDI cure and recurrence, and short and long-term safety outcomes. Results Of the first 259 participants enrolled at 20 sites, 222 had completed short-term follow-up at 1 month and 123 had follow-up to 6 months; 171 (66%) were female. All FMTs were done for CDI and 249 (96%) used an unknown donor (eg, stool bank). One-month cure occurred in 200 patients (90%); of these, 197 (98%) received only 1 FMT. Among 112 patients with initial cure who were followed to 6 months, 4 (4%) had CDI recurrence. Severe symptoms reported within 1-month of FMT included diarrhea (n = 5 [2%]) and abdominal pain (n = 4 [2%]); 3 patients (1%) had hospitalizations possibly related to FMT. At 6 months, new diagnoses of irritable bowel syndrome were made in 2 patients (1%) and inflammatory bowel disease in 2 patients (1%). Conclusions This prospective real-world study demonstrated high effectiveness of FMT for CDI with a good safety profile. Assessment of new conditions at long-term follow-up is planned as this registry grows and will be important for determining the full safety profile of FMT.
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    Iron in Micronutrient Powder Promotes an Unfavorable Gut Microbiota in Kenyan Infants
    (MDPI, 2017-07-19) Tang, Minghua; Frank, Daniel N.; Hendricks, Audrey E.; Ir, Diana; Esamai, Fabian; Liechty, Edward; Hambidge, K. Michael; Krebs, Nancy F.; Pediatrics, School of Medicine
    Iron supplementation may have adverse health effects in infants, probably through manipulation of the gut microbiome. Previous research in low-resource settings have focused primarily on anemic infants. This was a double blind, randomized, controlled trial of home fortification comparing multiple micronutrient powder (MNP) with and without iron. Six-month-old, non- or mildly anemic, predominantly-breastfed Kenyan infants in a rural malaria-endemic area were randomized to consume: (1) MNP containing 12.5 mg iron (MNP+Fe, n = 13); (2) MNP containing no iron (MNP−Fe, n = 13); or (3) Placebo (CONTROL, n = 7), from 6–9 months of age. Fecal microbiota were profiled by high-throughput bacterial 16S rRNA gene sequencing. Markers of inflammation in serum and stool samples were also measured. At baseline, the most abundant phylum was Proteobacteria (37.6% of rRNA sequences). The proteobacterial genus Escherichia was the most abundant genus across all phyla (30.1% of sequences). At the end of the intervention, the relative abundance of Escherichia significantly decreased in MNP−Fe (−16.05 ± 6.9%, p = 0.05) and CONTROL (−19.75 ± 4.5%, p = 0.01), but not in the MNP+Fe group (−6.23 ± 9%, p = 0.41). The second most abundant genus at baseline was Bifidobacterium (17.3%), the relative abundance of which significantly decreased in MNP+Fe (−6.38 ± 2.5%, p = 0.02) and CONTROL (−8.05 ± 1.46%, p = 0.01), but not in MNP-Fe (−4.27 ± 5%, p = 0.4445). Clostridium increased in MNP-Fe only (1.9 ± 0.5%, p = 0.02). No significant differences were observed in inflammation markers, except for IL-8, which decreased in CONTROL. MNP fortification over three months in non- or mildly anemic Kenyan infants can potentially alter the gut microbiome. Consistent with previous research, addition of iron to the MNP may adversely affect the colonization of potential beneficial microbes and attenuate the decrease of potential pathogens.
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    Methods in Lung Microbiome Research
    (American Thoracic Society, 2019-10-29) Carney, Sharon M.; Clemente, Jose C.; Cox, Michael J.; Dickson, Robert P.; Huang, Yvonne J.; Kitsios, Georgios D.; Kloepfer, Kirsten M.; Leung, Janice M.; LeVan, Tricia D.; Molyneaux, Philip L.; Moore, Bethany B.; O’Dwyer, David N.; Segal, Leopoldo N.; Garantziotis, Stavros; Pediatrics, School of Medicine
    The lung microbiome is associated with host immune response and health outcomes in experimental models and patient cohorts. Lung microbiome research is increasing in volume and scope; however, there are no established guidelines for study design, conduct, and reporting of lung microbiome studies. Standardized approaches to yield reliable and reproducible data that can be synthesized across studies will ultimately improve the scientific rigor and impact of published work and greatly benefit microbiome research. In this review, we identify and address several key elements of microbiome research: conceptual modeling and hypothesis framing; study design; experimental methodology and pitfalls; data analysis; and reporting considerations. Finally, we explore possible future directions and research opportunities. Our goal is to aid investigators who are interested in this burgeoning research area and hopefully provide the foundation for formulating consensus approaches in lung microbiome research.
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    Vaginal Glycogen, Not Estradiol, Is Associated With Vaginal Bacterial Community Composition in Black Adolescent Women
    (Elsevier, 2019-03-14) Nunn, Kenetta L.; Ridenhour, Benjamin J.; Chester, Emily M.; Vitzthum, Virginia J.; Fortenberry, J. Dennis; Forney, Larry J.; Pediatrics, School of Medicine
    Purpose The purpose of this study was to characterize the composition of vaginal bacterial communities in a cohort of Black adolescent women and to determine how the species composition of these communities correlate with levels of estradiol, glycogen, and stress. Methods Twenty-one Black adolescent women were sampled longitudinally. The composition of their vaginal communities was determined by analyzing the sequences of the Vl-V3 region of l6S rRNA genes and they were grouped based on patterns in species abundances. The relationships between estradiol, glycogen, psychosocial stress, and the composition of these communities were assessed. Results Vaginal communities could be distinguished and classified into three groups that differed in the abundances of Lactobacillus. Eighty-one percent of study participants had communities dominated by species of Lactobacillus. Glycogen levels were higher in communities dominated by one or multiple species of Lactobacillus as compared to those having low proportions of Lactobacillus. Estradiol and psychosocial stress measurements did not differ among the three groups, while estradiol and glycogen exhibited a weak positive relationship that was not statistically significant. Conclusions The findings of this pilot study suggest that glycogen levels are associated with vaginal community composition in young Black women; however, estradiol and psychosocial stress are not. Additionally, the results suggest there is no simple relationship between levels of estradiol and the production of vaginal glycogen.