Placental human papillomavirus infections and adverse pregnancy outcomes.

INTRODUCTION: Knowledge on prevalence and association of human papillomavirus (HPV) in third trimester placentae and adverse pregnancy outcomes is limited. We investigated the prevalence of placental HPV at delivery, explored urine HPV characteristics associated with placental HPV and whether placental HPV increased the risk adverse pregnancy outcomes. METHODS: Pregnant women were enrolled in the Scandinavian PreventADALL mother-child cohort study at midgestation. Human papillomavirus genotyping was performed on placental biopsies collected at delivery (n = 587) and first-void urine at midgestation and delivery (n = 556). Maternal characteristics were collected by questionnaires at gestational week 18 and 34. Adverse pregnancy outcomes were registered from chart data including hypertensive disorders of pregnancy, gestational diabetes mellitus and newborns small for gestational age. Uni- and multivariable regression models were used to investigate associations. RESULTS: Placental HPV was detected in 18/587 (3 %). Twenty-eight genotypes were identified among the 214/556 (38 %) with midgestational urine HPV. Seventeen of the 18 women with placental HPV were midgestational HPV positive with 89 % genotype concordance. Midgestational high-risk-(HR)-HPV and high viral loads of Any- or HR-HPV were associated with placental HPV. Persisting HPV infection from midgestation to delivery was not associated with placental HPV. Adverse pregnancy outcomes were seen in 2/556 (0.4 %) of women with placental HPV. DISCUSSION: In this general cohort of pregnant women, the prevalence of placental HPV was 3 %, and midgestational urinary HPV 38 %. High HPV viral load increased the risk for placental HPV infections. We observed no increased risk for adverse pregnancy outcomes in women with placental HPV.

Frequent oil-baths and skin barrier during infancy in the PreventADALL study.

BACKGROUND: In the general population randomized controlled PreventADALL trial, frequent emollient bath additives from 2 weeks of age did not prevent atopic dermatitis, while the effect on skin barrier function throughout infancy is not established. OBJECTIVE: The primary aim of this exploratory substudy was to assess the effect of mineral based oil-baths on transepidermal water loss (TEWL) and dry skin through infancy, and secondarily to explore if filaggrin (FLG) mutations modified the effect. METHODS: Overall 2153 infants randomized to Skin intervention (SI)(n=995) (oil-bath 4 times/week from 2 weeks through 8 months) or No skin intervention (NSI)(n=1158) with TEWL measurements at 3, 6 and/or 12 months of age were included, of whom 1683 infants also had available FLG mutation status. Effects of the skin intervention on TEWL and dry skin through infancy were assessed by mixed effects regression modelling. Background characteristics and protocol adherence were collected from electronic questionnaires, birth records and weekly diaries. RESULTS: The TEWL (95% CI) was in average 0.42 g/m2/h (0.13-0.70, p= 0.004) higher in the SI compared to NSI group through the first year of life, with significantly higher levels at 3 months, (8.6 (8.3-9.0) versus 7.6 (7.3-7.9)), but similar at 6 and 12 months. Dry skin was significantly more often observed in the NSI group compared to the SI group at 3 months (59% versus 51%) and at 6 months of age (63% versus 53%), while at 12 months of age, the difference was no longer significant. At 3 months, the TEWL of FLG mutation carriers was similar to the TEWL in SI group. No interaction between skin intervention and FLG mutation was found in the first year of life. CONCLUSIONS: Infants with frequent oil-baths from 2 weeks of age had reduced skin barrier function through infancy compared to controls, largely attributed to higher TEWL at 3 months of age, while the skin at 3 and 6 months appeared less dry in infants subjected to the skin intervention.

Birth mode is associated with development of atopic dermatitis in infancy and early childhood.

Background: Birth by caesarean section (CS) is associated with development of allergic diseases, but its role in the development of atopic dermatitis (AD) is less convincing. Objective: Our primary aim was to determine if birth mode was associated with AD in 3-year-olds and secondarily to determine if birth mode was associated with early onset and/or persistent AD in the first 3 years of life. Methods: We included 2129 mother-child pairs from the Scandinavian population-based prospective PreventADALL cohort with information on birth mode including vaginal birth, either traditional (81.3%) or in water (4.0%), and CS before (6.3%) and after (8.5%) onset of labor. We defined early onset AD as eczema at 3 months and AD diagnosis by 3 years of age. Persistent AD was defined as eczema both in the first year and at 3 years of age, together with an AD diagnosis by 3 years of age. Results: AD was diagnosed at 3, 6, 12, 24, and/or 36 months in 531 children (25%). Compared to vaginal delivery, CS was overall associated with increased odds of AD by 3 years of age, with adjusted odds ratio (95% confidence interval) of 1.33 (1.02-1.74), and higher odds of early onset AD (1.63, 1.06-2.48). The highest odds for early onset AD were observed in infants born by CS after onset of labor (1.83, 1.09-3.07). Birth mode was not associated with persistent AD. Conclusion: CS was associated with increased odds of AD by 3 years of age, particularly in infants presenting with eczema at 3 months of age.

Spatiotemporal succession of phosphorous accumulating biofilms during the first year of establishment.

Many wastewater treatment plants are dependent on the utilization of microorganisms in biofilms. Our knowledge about the establishment of these biofilms is limited, particular with respect to biofilms involved in enhanced biological phosphorus removal (EBPR). These biofilms rely on polyphosphate-accumulating organisms (PAOs), requiring alternating oxic and anaerobic conditions for phosphorous uptake. This challenge has been solved using the Hias process, which combines moving-bed biofilm-reactor (MBBR) technology with physical transfer of biofilm-carriers from oxic to anaerobic zones. We combined biofilm fractionation with temporal analyses to unveil the establishment in the Hias process. A stable phosphorous removal efficiency of >95% was reached within 16 weeks of operation. Phosphorus removal, however, was not correlated with the establishment of known PAOs. The biofilms seemed associated with an outer microbiota layer with rapid turnover and an inner layer with a slow expansion. The inner layer showed an overrepresentation of known PAOs. In conclusion, our spatiotemporal analyses of phosphorous accumulating biofilm establishment lead to a new model for biofilm growth, while the mechanisms for phosphorous removal remain largely unresolved.

Effects of a low FODMAP diet on gut microbiota in individuals with treated coeliac disease having persistent gastrointestinal symptoms - a randomised controlled trial.

Individuals with coeliac disease (CeD) often experience gastrointestinal symptoms despite adherence to a gluten-free diet (GFD). While we recently showed that a diet low in fermentable oligo-, di-, monosaccharides and polyols (FODMAP) successfully provided symptom relief in GFD-treated CeD patients, there have been concerns that the low FODMAP diet (LFD) could adversely affect the gut microbiota. Our main objective was therefore to investigate whether the LFD affects the faecal microbiota and related variables of gut health. In a randomised controlled trial GFD-treated CeD adults, having persistent gastrointestinal symptoms, were randomised to either consume a combined LFD and GFD (n 39) for 4 weeks or continue with GFD (controls, n 36). Compared with the control group, the LFD group displayed greater changes in the overall faecal microbiota profile (16S rRNA gene sequencing) from baseline to follow-up (within-subject ß-diversity, P < 0·001), characterised by lower and higher follow-up abundances (%) of genus Anaerostipes (Pgroup < 0·001) and class Erysipelotrichia (Pgroup = 0·02), respectively. Compared with the control group, the LFD led to lower follow-up concentrations of faecal propionic and valeric acid (GC-FID) in participants with high concentrations at baseline (Pinteraction ≤ 0·009). No differences were found in faecal bacterial α-diversity (Pgroup ≥ 0·20) or in faecal neutrophil gelatinase-associated lipocalin (ELISA), a biomarker of gut integrity and inflammation (Pgroup = 0·74), between the groups at follow-up. The modest effects of the LFD on the gut microbiota and related variables in the CeD patients of the present study are encouraging given the beneficial effects of the LFD strategy to treat functional GI symptoms (Registered at clinicaltrials.gov as NCT03678935).

A Globally Distributed Bacteroides caccae Strain Is the Most Prevalent Mother-Child Shared Bacteroidaceae Strain in a Large Scandinavian Cohort.

Bacteroides and Phocaeicola, members of the family Bacteroidaceae, are among the first microbes to colonize the human infant gut. While it is known that these microbes can be transmitted from mother to child, our understanding of the specific strains that are shared and potentially transmitted is limited. In this study, we aimed to investigate the shared strains of Bacteroides and Phocaeicola in mothers and their infants. We analyzed fecal samples from pregnant woman recruited at 18 weeks of gestation from the PreventADALL study, as well as offspring samples from early infancy, including skin swab samples taken within 10 min after birth, the first available fecal sample (meconium), and fecal samples at 3 months of age. We screened 464 meconium samples for Bacteroidaceae, with subsequent selection of 144 mother-child pairs for longitudinal analysis, based on the presence of Bacteroidaceae, longitudinal sample availability, and delivery mode. Our results showed that Bacteroidaceae members were mainly detected in samples from vaginally delivered infants. We identified high prevalences of Phocaeicola vulgatus, Phocaeicola dorei, Bacteroides caccae, and Bacteroides thetaiotaomicron in mothers and vaginally born infants. However, at the strain level, we observed high prevalences of only two strains: a B. caccae strain and a P. vulgatus strain. Notably, the B. caccae strain was identified as a novel component of mother-child shared strains, and its high prevalence was also observed in publicly available metagenomes worldwide. Our findings suggest that mode of delivery may play a role in shaping the early colonization of the infant gut microbiota, in particular the colonization of Bacteroidaceae members. IMPORTANCE Our study provides evidence that Bacteroidaceae strains present on infants' skin within 10 min after birth, in meconium samples, and in fecal samples at 3 months of age in vaginally delivered infants are shared with their mothers. Using strain resolution analyses, we identified two strains, belonging to Bacteroides caccae and Phocaeicola vulgatus, as shared between mothers and their infants. Interestingly, the B. caccae strain showed a high prevalence worldwide, while the P. vulgatus strain was less common. Our findings also showed that vaginal delivery was associated with early colonization of Bacteroidaceae members, whereas cesarean section delivery was associated with delayed colonization. Given the potential for these microbes to influence the colonic environment, our results suggest that understanding the bacterial-host relationship at the strain level may have implications for infant health and development later in life.

Metagenome-mining indicates an association between bacteriocin presence and strain diversity in the infant gut.

BACKGROUND: Our knowledge about the ecological role of bacterial antimicrobial peptides (bacteriocins) in the human gut is limited, particularly in relation to their role in the diversification of the gut microbiota during early life. The aim of this paper was therefore to address associations between bacteriocins and bacterial diversity in the human gut microbiota. To investigate this, we did an extensive screening of 2564 healthy human gut metagenomes for the presence of predicted bacteriocin-encoding genes, comparing bacteriocin gene presence to strain diversity and age. RESULTS: We found that the abundance of bacteriocin genes was significantly higher in infant-like metagenomes (< 2 years) compared to adult-like metagenomes (2-107 years). By comparing infant-like metagenomes with and without a given bacteriocin, we found that bacteriocin presence was associated with increased strain diversities. CONCLUSIONS: Our findings indicate that bacteriocins may play a role in the strain diversification during the infant gut microbiota establishment.

Decreased serum concentrations of antiseizure medications in children with drug resistant epilepsy following treatment with ketogenic diet.

OBJECTIVE: To examine the potential influence of a ketogenic diet on serum concentrations of antiseizure medications (ASMs) in children with drug resistant epilepsy. METHODS: We investigated the serum concentrations of ASMs in 25 children with drug resistant epilepsy, 2-13 years of age, treated with a classical ketogenic diet for 12 weeks. The patients were recruited from the National Centre for Epilepsy from August 15th, 2017, to January 24th, 2022. Changes in ASM serum concentrations were analyzed using a mixed effect model analysis. Significance level was set at P < 0.05 for all comparisons. RESULTS: The participants used 12 different ASMs during the study. The mean number of ASMs was 2.4 (±SD 0.7). None of the participants changed the type or dose of the ASMs during the intervention period. The serum concentrations of clobazam (n = 9, P = 0.002), desmethylclobazam (n = 9, P = 0.010), and lamotrigine (n = 6, P = 0.016) decreased significantly during the dietary treatment. The analytes with the largest reduction in serum concentration after 12 weeks of dietary treatment were clobazam (mean change -38%) and desmethylclobazam (mean change -37%). We found no significant change in the serum concentrations of levetiracetam, topiramate, and valproic acid. SIGNIFICANCE: We identified a significant decrease in the serum concentrations of clobazam, desmethylclobazam, and lamotrigine following a 12-week ketogenic diet intervention in children with drug resistant epilepsy. An unintended decrease in the serum concentrations of ASMs may render the patient prone to seizures. Measurements of ASM serum concentrations might be useful in patients on a ketogenic diet, especially in patients with lack of efficacy of the dietary treatment.

The skin microbiome in the first year of life and its association with atopic dermatitis.

BACKGROUND: Early-life microbial colonization of the skin may modulate the immune system and impact the development of atopic dermatitis (AD) and allergic diseases later in life. To address this question, we assessed the association between the skin microbiome and AD, skin barrier integrity and allergic diseases in the first year of life. We further explored the evolution of the skin microbiome with age and its possible determinants, including delivery mode. METHODS: Skin microbiome was sampled from the lateral upper arm on the first day of life, and at 3, 6, and 12 months of age. Bacterial communities were assessed by 16S rRNA gene amplicon sequencing in 346 infants from the PreventADALL population-based birth cohort study, representing 970 samples. Clinical investigations included skin examination and skin barrier function measured as trans-epidermal water loss (TEWL) at the site and time of microbiome sampling at 3, 6, and 12 months. Parental background information was recorded in electronic questionnaires, and delivery mode (including vaginal delivery (VD), VD in water, elective caesarean section (CS) and emergency CS) was obtained from maternal hospital charts. RESULTS: Strong temporal variations in skin bacterial community composition were found in the first year of life, with distinct patterns associated with different ages. Confirming our hypothesis, skin bacterial community composition in the first year of life was associated with skin barrier integrity and later onsets of AD. Delivery mode had a strong impact on the microbiome composition at birth, with each mode leading to distinct patterns of colonization. Other possible determinants of the skin microbiome were identified, including environmental and parental factors as well as breastfeeding. CONCLUSION: Skin microbiome composition during infancy is defined by age, transiently influenced by delivery mode as well as environmental, parental factors and breastfeeding. The microbiome is also associated with skin barrier integrity and the onset of AD.

Prediction of high fecal propionate-to-butyrate ratios using 16S rRNA-based detection of bacterial groups with liquid array diagnostics.

Butyrate and propionate represent two of three main short-chain fatty acids produced by the intestinal microbiota. In healthy populations, their levels are reportedly equimolar, whereas a deviation in their ratio has been observed in various diseased cohorts. Monitoring such a ratio represents a valuable metric; however, it remains a challenge to adopt short-chain fatty acid detection techniques in clinical settings because of the volatile nature of these acids. Here we aimed to estimate short-chain fatty acid information indirectly through a novel, simple quantitative PCR-compatible assay (liquid array diagnostics) targeting a limited number of microbiome 16S markers. Utilizing 15 liquid array diagnostics probes to target microbiome markers selected by a model that combines partial least squares and linear discriminant analysis, the classes (normal vs high propionate-to-butyrate ratio) separated at a threshold of 2.6 with a prediction accuracy of 96%.

Maternal food-avoidance diets and dietary supplements during breastfeeding.

AIMS: To identify maternal food-avoidance diets and dietary supplement use during breastfeeding, and to explore factors associated with food avoidance diets. DESIGN: A prospective mother-child birth cohort study. METHODS: Electronic questionnaires were answered by 1,462 breastfeeding mothers 6 months postpartum in the Preventing Atopic Dermatitis and Allergies in Children (PreventADALL) study from 2014-2016. Demographic and antenatal factors were analysed for associations with food avoidance diets in 1,368 women by multiple logistic regression. RESULTS: Overall, 289 breastfeeding women (19.8%) avoided at least one food item in their diet, most commonly cow's milk in 99 women (6.8%). Foods were most often avoided due to conditions in the child, maternal factors or lifestyle choice. The odds for food avoidance diets were 2.1 (95% CI: 1.3, 3.4) for food allergy (presumed or diagnosed) and 19.4 (5.4, 70.1) for celiac disease in the mother. Dietary supplements were reported by nearly 80%, most commonly cod liver oil.

The effect of nicotine-containing products and fetal sex on placenta-associated circulating midpregnancy biomarkers.

BACKGROUND: In utero exposure to nicotine, largely assessed by smoking, is a risk factor for impaired offspring health, while potential effects of non-combustible nicotine use such as snus (oral moist tobacco), are less well-known. Maternal serum concentrations of placental growth factor (PlGF) and soluble fms-like tyrosine kinase-1 (sFlt-1) may be viewed as "placenta health markers", known to differ by fetal sex. Maternal smoking during pregnancy has been associated with lower levels of circulating sFlt-1, while the effect of snus on placenta-associated angiogenic factors is unknown. Our aim was to explore if snus and/or smoking exposure was associated with midpregnancy maternal levels of sFlt-1, PlGF and sFlt-1/PlGF ratio if these associations were modified by fetal sex. METHODS: Midpregnancy (16-22 gestational weeks) serum from 2603 Scandinavian women enrolled in the population-based multi-center PreventADALL (Preventing Atopic Dermatitis and ALLergies in children) study was analysed for sFlt-1 and PlGF concentrations by electrochemiluminescence, deriving the sFlt-1/PGF ratio. Nicotine use was assessed by electronic questionnaires at enrollment in 2278 of the women. Univariable and multivariable linear regression models on log transformed outcomes were used to assess the association between nicotine use and biomarker levels. Interaction terms were included to identify whether the associations were modified by fetal sex. RESULTS: Median sFlt-1, PlGF and sFlt-1/PlGF ratios among women with nicotine exposure information were similar to those of all included women and differed by fetal sex. Current snus use was significantly associated with reduced maternal circulating PlGF levels in adjusted analyses [ß - 0.12, (95% CI - 0.20; 0.00) compared to never use, p = 0.020]. A significant interaction between fetal sex and snus exposure was observed for PIGF (p = 0.031). Prior or periconceptional snus use was significantly associated with PIGF in male fetus pregnancies [ß - 0.05 (95% CI - 0.09 to (- 0.02)) and ß - 0.07 (95% CI - 0.12 to (- 0.02)) compared to never use, p = 0.002]. Smoking was not significantly associated with any circulating biomarkers levels. CONCLUSIONS: Midpregnancy maternal angiogenic profile differed by periconceptional snus use and fetal sex. Snus exposure, perceived as "safe" by users, before or during pregnancy seems to affect midpregnancy placental health in a sex dimorphic manner.

Bacterial Butyrate in Parkinson's Disease Is Linked to Epigenetic Changes and Depressive Symptoms.

BACKGROUND: The gut microbiome and its metabolites can impact brain health and are altered in Parkinson's disease (PD) patients. It has been recently demonstrated that PD patients have reduced fecal levels of the potent epigenetic modulator butyrate and its bacterial producers. OBJECTIVES: Here, we investigate whether the changes in the gut microbiome and associated metabolites are related to PD symptoms and epigenetic markers in leucocytes and neurons. METHODS: Stool, whole blood samples, and clinical data were collected from 55 PD patients and 55 controls. We performed DNA methylation analysis on whole blood samples and analyzed the results in relation to fecal short-chain fatty acid concentrations and microbiota composition. In another cohort, prefrontal cortex neurons were isolated from control and PD brains. We identified genome-wide DNA methylation by targeted bisulfite sequencing. RESULTS: We show that lower fecal butyrate and reduced counts of genera Roseburia, Romboutsia, and Prevotella are related to depressive symptoms in PD patients. Genes containing butyrate-associated methylation sites include PD risk genes and significantly overlap with sites epigenetically altered in PD blood leucocytes, predominantly neutrophils, and in brain neurons, relative to controls. Moreover, butyrate-associated methylated-DNA regions in PD overlap with those altered in gastrointestinal (GI), autoimmune, and psychiatric diseases. CONCLUSIONS: Decreased levels of bacterially produced butyrate are related to epigenetic changes in leucocytes and neurons from PD patients and to the severity of their depressive symptoms. PD shares common butyrate-dependent epigenetic changes with certain GI and psychiatric disorders, which could be relevant for their epidemiological relation. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Genome-wide decrease in DNA methylation in adults with epilepsy treated with modified ketogenic diet: A prospective study.

OBJECTIVE: The aim of this study was to investigate the impact of the modified ketogenic diet on DNA methylation in adults with epilepsy. METHODS: In this prospective study, we investigated the genome-wide DNA methylation in whole blood in 58 adults with epilepsy treated with the modified ketogenic for 12 weeks. Patients were recruited from the National Center for Epilepsy, Norway, from March 1, 2011 to February 28, 2017. DNA methylation was analyzed using the Illumina Infinium MethylationEPIC BeadChip array. Analysis of variance and paired t-test were used to identify differentially methylated loci after 4 and 12 weeks of dietary treatment. A false discovery rate approach with a significance threshold of <5% was used to adjust for multiple comparisons. RESULTS: We observed a genome-wide decrease in DNA methylation, both globally and at specific sites, after 4 and 12 weeks of dietary treatment. A substantial share of the differentially methylated positions (CpGs) were annotated to genes associated with epilepsy (n = 7), lipid metabolism (n = 8), and transcriptional regulation (n = 10). Furthermore, five of the identified genes were related to inositol phosphate metabolism, which may represent a possible mechanism by which the ketogenic diet attenuates seizures. SIGNIFICANCE: A better understanding of the modified ketogenic diet's influence at the molecular level may be the key to unraveling the mechanisms by which the diet can ameliorate seizures and possibly to identifying novel therapeutic targets for epilepsy.

Early food intervention and skin emollients to prevent food allergy in young children (PreventADALL): a factorial, multicentre, cluster-randomised trial.

BACKGROUND: Primary prevention of food allergy by early introduction of allergenic foods seems promising. We aimed to determine whether early food introduction or the application of regular skin emollients in infants from a general population reduced the risk of food allergy. METHODS: This 2 × 2 factorial, cluster-randomised trial was done at Oslo University Hospital and Østfold Hospital Trust, Oslo, Norway, and Karolinska University Hospital, Stockholm, Sweden. Infants of women recruited antenatally at the routine 18-week ultrasound examination were cluster-randomised at birth to the following groups: (1) no intervention group; (2) the skin intervention group (skin emollients; bath additives and facial cream; from age 2 weeks to <9 months, both at least four times per week); (3) the food intervention group (early complementary feeding of peanut, cow's milk, wheat, and egg from age 3 months); or (4) combined intervention group (skin and food interventions). Participants were randomly assigned (1:1:1:1) using computer-generated randomisation based on clusters of 92 geographical areas and eight 3-month time blocks. Study personnel performing clinical assessments were masked to group allocation. The primary outcome was allergy to any interventional food at 36 months of age. The primary efficacy analysis was done by intention-to-treat analysis, which included all participants who were randomly assigned, apart from three individuals who withdrew their consent. This was a study performed within ORAACLE (the Oslo Research Group of Asthma and Allergy in Childhood; the Lung and Environment). This study is registered as ClinicalTrials.gov, NCT02449850. FINDINGS: We recruited 2697 women with 2701 pregnancies, from whom 2397 newborn infants were enrolled between April 14, 2015, and April 11, 2017. Of these infants, 597 were randomly assigned to the no intervention group, 575 to the skin intervention group, 642 to the food intervention group, and 583 to the combined intervention group. One participant in each of the no intervention, food intervention, and skin intervention groups withdrew consent and were therefore not included in any analyses. Food allergy was diagnosed in 44 children; 14 (2·3%) of 596 infants in the non-intervention group, 17 (3·0%) of 574 infants in the skin intervention group, six (0·9%) of 641 infants in the food intervention group, and seven (1·2%) of 583 infants in the combined intervention group. Peanut allergy was diagnosed in 32 children, egg allergy in 12 children, and milk allergy in four children. None had allergy to wheat. Prevalence of food allergy was reduced in the food intervention group compared with the no food intervention group (risk difference -1·6% [95% CI -2·7 to -0·5]; odds ratio [OR] 0·4 [95% CI 0·2 to 0·8]), but not compared with the skin intervention group (0·4% [95% CI -0·6 to 1· 5%]; OR 1·3 [0·7 to 2·3]), with no significant interaction effect (p=1·0). Preventing food allergy in one child required early exposure to allergenic foods in 63 children. No serious adverse events were observed. INTERPRETATION: Exposure to allergenic foods from 3 months of age reduced food allergy at 36 months in a general population. Our results support that early introduction of common allergenic foods is a safe and effective strategy to prevent food allergy. FUNDING: Full funding sources listed at end of paper (see Acknowledgments).

Spatial fractionation of phosphorus accumulating biofilm: stratification of polyphosphate accumulation and dissimilatory nitrogen metabolism.

The spatial distribution of microorganisms represents a critical issue in understanding biofilm function. The aim of the current work was to develop a method for biofilm fractionation, facilitating the analysis of individual spatial biofilm layers using metagenomic approaches. Phosphorus accumulating biofilm applied in an enhanced biological phosphorus removal wastewater treatment plant, were fractionated, and analyzed. The fractionated biofilm revealed a surprising spatial distribution of bacteria and genes, where potential polyphosphate accumulating organisms account for ∼ 47% of the inner layer microbiome. A spatial distribution of genes involved in dissimilatory nitrogen reduction was observed, indicating that different layers of the biofilm were metabolically active during the anoxic and aerobic zones of the phosphorus removal process. The physical biofilm separation into individual fractions unveiled functional layers of the biofilm, which will be important for future understanding of the phosphorus removal wastewater process.

Impaired skin barrier and allergic sensitization in early infancy.

BACKGROUND: Factors predicting allergic sensitization in the first 6 months of life are poorly understood. We aimed to determine whether eczema, dry skin, and high transepidermal water loss (TEWL) at 3 months were associated with allergic sensitization at 6 months of age and, secondarily, to establish whether these characteristics predicted sensitization from 3 to 6 months of age. METHODS: At 3 months of age, 1,994 infants from the population-based PreventADALL birth cohort in Norway and Sweden were assessed for eczema and dry skin on the cheeks and/or extensors; impaired skin barrier function, defined as TEWL in the upper quartile (>9.4 g/m2 /h), and allergen-specific IgE levels <0.1 kUA /L, available in 830. At 6 months, we assessed allergic sensitization to any food (egg, cow's milk, peanut, wheat, soy) or inhalant (birch, timothy grass, dog, and cat) allergen by a skin prick test wheal diameter ≥2 mm larger than negative control. RESULTS: Any sensitization was found in 198 of the 1,994 infants (9.9%), the majority to food allergens (n = 177, 8.9%). Eczema, dry skin, and high TEWL at 3 months increased the risk of sensitization at 6 months; adjusted odds ratios 4.20 (95% CI 2.93-6.04), 2.09 (95% CI 1.51-2.90) and 3.67 (95% CI 2.58-5.22), respectively. Eczema predicted sensitization with 55.6% sensitivity and 68.1% specificity; dry skin with 65.3% sensitivity and 57.3% specificity; and high TEWL with 61.7% sensitivity and 78.1% specificity. CONCLUSION: Eczema, dry skin, and high TEWL at 3 months predicted allergic sensitization at 6 months of age.

Naturalizing laboratory mice by housing in a farmyard-type habitat confers protection against colorectal carcinogenesis.

Living in a farm environment in proximity to animals is associated with reduced risk of developing allergies and asthma, and has been suggested to protect against other diseases, such as inflammatory bowel disease and cancer. Despite epidemiological evidence, experimental disease models that recapitulate such environments are needed to understand the underlying mechanisms. In this study, we show that feralizing conventional inbred mice by continuous exposure to a livestock farmyard-type environment conferred protection toward colorectal carcinogenesis. Two independent experimental approaches for colorectal cancer induction were used; spontaneous (Apc Min/+ mice on an A/J background) or chemical (AOM/DSS). In contrast to conventionally reared laboratory mice, the feralized mouse gut microbiota structure remained stable and resistant to mutagen- and colitis-induced neoplasia. Moreover, the feralized mice exhibited signs of a more mature immunophenotype, indicated by increased expression of NK and T-cell maturation markers, and a more potent IFN-γ response to stimuli. In our study, hygienically born and raised mice subsequently feralized post-weaning were protected to a similar level as life-long exposed mice, although the greatest effect was seen upon neonatal exposure. Collectively, we show protective implications of a farmyard-type environment on colorectal cancer development and demonstrate the utility of a novel animal modeling approach that recapitulates realistic disease responses in a naturalized mammal.

Allergy-related diseases and early gut fungal and bacterial microbiota abundances in children.

BACKGROUND: The early gut microbiota has been proposed as an important link between environmental exposures and development of allergy-related diseases. Beyond the widely investigated associations between the gut bacterial microbiota, we investigated the involvement of early gut mycobiota and gut permeability in the pathogenesis of asthma, allergic rhinoconjunctivitis (AR) and eczema. METHODS: In the Probiotics in the Prevention of Allergy among Children in Trondheim trial with maternal probiotic supplementation, we collected faecal samples at four timepoints between 0 and 2 years from a cohort of 278 children. Clinical information on allergy-related diseases was collected in a paediatric examination at 2 years and questionnaires at 6 weeks and 1, 2 and 6 years. By quantitative PCR and 16S/ITS1 MiSeq rRNA gene sequencing, we analysed the gut bacterial and fungal microbiota abundance and bacterial diversity and explored associations with allergy-related diseases. We also measured gut permeability markers (lipopolysaccharide-binding protein [LBP] and fatty acid-binding protein 2 [FABP2]). RESULTS: Children with higher fungal abundance at 2 years were more likely to develop asthma and AR by 6 years, odds ratios 1.70 (95% CI: 1.06-2.75) and 1.41 (1.03-1.93), respectively. We explored causal connections, and children with eczema at 1-2 years appeared to have more mature bacterial microbiota, as well as being depleted of Enterococcus genus. Although LBP and FABP2 did not correlate with eczema, increased bacterial abundance was associated with increased serum FABP2. CONCLUSIONS: We observed positive associations between gut fungal abundance and allergy-related disease, but increased gut permeability does not appear to be involved in the underlying mechanisms for this association. Our findings should be confirmed in future microbiota studies.