•Pipe material has a clear influence on biomass and bacterial community composition.•PVCC is the preferred material to control microbial growth in drinking water systems.•PVC-P and copper have a ...distinct bacterial community compared to other materials.•Fungi are dominant in water and V. vermiformis is dominant in biofilm.
Biodegradable compounds can cause undesired microbial growth in drinking water systems and these compounds can originate from the water or pipe materials used in drinking water systems. The aim of our study was to determine the influence of different pipe materials on the microbial populations in water and biofilm under semi-stagnant conditions. The microbial communities in biofilm and water, which were in contact with seven different materials, were characterized by determining ATP concentrations, microbial composition gene copy numbers of some specific microbial groups. The ATP concentration in water and biofilm varied between the different materials with glass (negative control) < copper < PVCC < PE-Xc < PE-Xb < PE-100 < PVC-P. Gene copy numbers of Legionella spp., Mycobacterium spp., Pseudomonas spp., Aeromonas spp., fungi and Vermamoeba vermiformis were also higher for PVC-P and PE than for glass, copper and PVCC. The bacterial community composition in water and biofilm varied between materials as well. PERMANOVA and CAP analysis demonstrated that copper and PVC-P are different when compared to the other materials. Furthermore, bacterial community composition and ATP concentrations in water and biofilm were similar after eight and 16 weeks incubation, but differed from results obtained after one week. Finally, the ATP, the specific microbial groups and the bacterial community composition also differed between water and biofilm on each material. We conclude from our study that pipe material is an important factor that influences the biomass concentration, abundance of specific microorganisms and the bacterial community composition in distribution systems with unchlorinated drinking water.
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Carpal tunnel syndrome (CTS) is a common entrapment neuropathy. Electrodiagnostic testing (EMG) is used to confirm the diagnosis. It is not known what the diagnostic accuracy of high-resolution ...sonography is in comparison to EMG.
The aim of this study was to compare the diagnostic accuracy of both tests in CTS patients.
A prospective cohort of 207 patients with possible CTS underwent high-resolution sonography and EMG. The diagnosis of CTS was based on clinical signs and symptoms. The cross-sectional area of the median nerve at the carpal tunnel inlet and at the distal one-third level of the forearm was assessed by an investigator, blinded to the clinical and EMG data. Normal sonographic values were obtained from 137 controls. All patients and 40 controls underwent a standardised nerve conduction study. The kappa coefficient was used to evaluate the relationship between sonography, EMG and clinical diagnosis.
The cross-sectional area at the distal one-third of the forearm was not significantly different between the controls and patients (p = 0.59), whereas the cross-sectional area at the carpal tunnel inlet was significantly increased in the patient group (p<0.0001). The kappa coefficient for EMG using the median-ulnar distal sensory latency difference versus clinical evaluation was 0.64 and, for sonography, this coefficient was 0.69; these were not statistically different (p = 0.37). Combining the two tests resulted in a kappa coefficient of 0.72, which was not significantly different from sonography alone (p = 0.73).
In patients with a clinical diagnosis of CTS, the accuracy of sonography is similar to that for EMG. Sonography is probably preferable because it is painless, easily accessible and preferred by the patients.
An important practical limitation of the three-dimensional geometry of stem-cell derived intestinal organoids is that it prevents easy access to the apical epithelium for testing food components, ...microorganisms, bioactive and toxic compounds. To this end, we here report on a new robust method for generating confluent intestinal cell monolayers from single-cell suspensions of enzymatically-dissociated porcine organoids using modified culture conditions. With this method, cell seeding densities can be standardised, overcoming problems with methods based on mechanical dissociation of organoids. Confluent monolayers formed tight junctions with high transepithelial electrical resistance in three days and could be used in experiments for up to two weeks. Multilineage differentiation of ileal stem cells was demonstrated by immunohistochemistry and RT-qPCR of cell-specific transcripts, also unequivocally confirming the controversial existence of Paneth-like cells in the porcine small intestine. The method described here is useful to standardize primary epithelial monolayer formation from intestinal organoids and allows rapid and robust studies of intestinal physiology.
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•Rapid establishment of 3-D and 2-D cultures of porcine intestinal organoids•Generation of a robust in vitro organoid model for physiological studies•Monolayers contain multilineage cell populations•Organoid model to facilitate luminal exposure to substances•Existence of Paneth-like cells demonstrated in pig ileum
Probiotics, prebiotics and synbiotics have been suggested as dietary strategies to improve intestinal barrier function. This study aimed to assess the effect of two weeks synbiotic supplementation on ...intestinal permeability under basal and stressed conditions. Secondary aims were the assessment of two weeks synbiotic supplementation on systemic immune function and gastrointestinal symptoms including defecation pattern.
Twenty healthy adults completed a double-blind, controlled, randomized, parallel design study.
Groups either received synbiotic (1.5 × 1010 CFU Ecologic® 825 + 10 g fructo-oligosaccharides (FOS P6) per day) or control supplements for two weeks.
Intestinal segment specific permeability was assessed non-invasively by oral administration of multiple sugar probes and, subsequently, assessing the excretion of these probes in urine. This test was conducted at baseline and at the end of intervention, in the absence and in the presence of an indomethacin challenge. Indomethacin was applied to induce a compromised gut state. Plasma zonulin, cytokines and chemokines were measured at baseline and at the end of intervention. Gastrointestinal symptoms and stool frequency were recorded at baseline and daily during intervention.
Significantly more male subjects were in the synbiotic group compared to the control group (P = 0.025). Indomethacin significantly increased urinary lactulose/rhamnose ratio versus without indomethacin, both in the control group (P = 0.005) and in the synbiotic group (P = 0.017). Urinary sugar recoveries and ratios, plasma levels of zonulin, cytokines and chemokines, and gastrointestinal symptom scores were not significantly different after control or synbiotic intervention. Stool frequency within the synbiotic group was significantly increased during synbiotic intervention compared to baseline (P = 0.039) and higher compared to control intervention (P = 0.045).
Two weeks Ecologic® 825/FOS P6 supplementation increased stool frequency, but did not affect intestinal permeability neither under basal nor under indomethacin-induced stressed conditions, immune function or gastrointestinal symptoms in healthy adults.
Background: Modification of the intestinal microbiota by administration of probiotic bacteria may be a potential approach to prevent allergic disease. We aimed to study primary prevention of ...allergic disease in high‐risk children by pre‐ and postnatal supplementation of selected probiotic bacteria.
Methods: In a double‐blind, randomized, placebo‐controlled trial, a mixture of probiotic bacteria selected by in‐vitro experiments (Bifidobacterium bifidum, Bifidobacterium lactis, and Lactococcus lactis; Ecologic® Panda) was prenatally administered to mothers of high‐risk children (i.e. positive family history of allergic disease) and to their offspring for the first 12 months of life.
Results: Parental‐reported eczema during the first 3 months of life was significantly lower in the intervention group compared with placebo, 6/50 vs 15/52 (P = 0.035). After 3 months, the incidence of eczema was similar in both groups. Cumulative incidence of parental‐reported eczema at 1 and 2 years was 23/50 (intervention) vs 31/48 (placebo) and 27 (intervention) vs 34 (placebo), respectively. The number needed to treat was 5.9 at age 3 and 12 months and 6.7 at age 2 years. The intervention group was significantly more frequently colonized with higher numbers of Lc. lactis. Furthermore, at age 3 months, in vitro production of IL‐5 (146 pg/ml vs 72 pg/ml; P = 0.04) was decreased in the probiotic‐group compared with the placebo‐group.
Conclusions: This particular combination of probiotic bacteria shows a preventive effect on the incidence of eczema in high‐risk children, which seems to be sustained during the first 2 years of life. In addition to previous studies, the preventive effect appears to be established within the first 3 months of life.
Maternal prenatal psychosocial stress is associated with altered child emotional and behavioral development. One potential underlying mechanism is that prenatal psychosocial stress affects child ...outcomes via the mother's, and in turn the child's, intestinal microbiota. This study investigates the first step of this mechanism: the relation between psychosocial stress and fecal microbiota in pregnant mothers. Mothers (N = 70) provided a late pregnancy stool sample and filled in questionnaires on general and pregnancy-specific stress and anxiety. Bacterial DNA was extracted and analysed by Illumina HiSeq sequencing of PCR-amplified 16 S ribosomal RNA gene fragments. Associations between maternal general anxiety and microbial composition were found. No associations between the other measured psychosocial stress variables and the relative abundance of microbial groups were detected. This study shows associations between maternal pregnancy general anxiety and microbial composition, providing first evidence of a mechanism through which psychological symptoms in pregnancy may affect the offspring.
•The effect of salt (NaCl) on biological nitrogen removal was studied.•Nitrification process is inhibited at high salt concentrations (⩾24.1g NaCl/L).•Ammonia oxidizing bacterial communities were ...studied by 454-pyrosequencing.•Only 5 OTUs of 42 OTUs were found at all salinities tested.•amoA sequences related to Nitrosospira disappeared at high salinity.
The effect of salt (NaCl) on biological nitrogen removal and community structure of ammonia-oxidizing bacteria (AOB) was investigated in a submerged fixed bed bioreactor (SFBBR). Influent wastewater was supplemented with NaCl at 0 (control), 3.7, 24.1 and 44.1g/L, and the rate of ammonia removal efficiency was measured by ion chromatography. The structure of the AOB community was profiled by 454-pyrosequencing, based on the amplification of partial ammonia-monooxygenase subunit A (amoA) genes. Salinity did not inhibit nitrification at 3.7g/L, while ammonia oxidation activity significantly decreased and nitrite was consequently accumulated in the SFBBR when the salt concentration was ⩾24.1g/L. The sequencing of amoA genes revealed that many of the OTUs found in the control experiment were still present at the full range of NaCl studied, while concentrations of 24.1 and 44.1g of NaCl/L promoted the emergence of new OTUs phylogenetically related to AOB described in saline environments.
To keep the high quality of drinking water in the future for non-chlorinated drinking water systems, knowledge about the variables that most strongly affect this quality is necessary in order to know ...where to focus on and possibly even change aspects of drinking water production and distribution. Therefore, the aim of this study was to investigate which variables (source of drinking water, growth potential and pipe material type) have the biggest influence on bacterial community composition and biomass concentration of drinking water and biofilm in distribution systems. Ten different distribution systems were sampled for water and biofilm, obtained from four different pipe materials, throughout the Netherlands. The distribution systems are supplied either with drinking water produced from groundwater or surface water, and differ in drinking water quality parameters such as the growth potential. We found a significant relationship for growth potential and ATP concentration in water, but for the ATP in the biofilm none of the parameters showed a significant effect. Furthermore, the source of the drinking water and the pipe material did not significantly affect the ATP concentration in water and biofilm. The bacterial composition of in both water and biofilm was significantly different between distribution systems delivering water with low and high growth potential and between drinking water produced from groundwater or surface water. In contrast, the different pipe materials did not significantly affect composition of biofilm-associated communities. We conclude from these results that the growth potential of the treated water best explains the variation in biomass and bacterial composition in water and biofilm of non-chlorinated drinking water distribution systems followed by the drinking water source, whereas pipe materials seem to be of lesser importance.
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•Microbiology in Dutch unchlorinated drinking water distribution systems was studied.•Growth potential best explains the variation of the bacterial composition.•Source of drinking water did not significantly affect bacterial composition in biofilm.•Different pipe materials did not significantly affect bacterial composition in biofilm.
Complex interactions between rumen microbiota, cow genetics, and diet composition may exist. Therefore, the effect of linseed oil, DGAT1 K232A polymorphism (DGAT1), and the interaction between ...linseed oil and DGAT1 on CH4 and H2 emission, energy and N metabolism, lactation performance, ruminal fermentation, and rumen bacterial and archaeal composition was investigated. Twenty-four lactating Holstein-Friesian cows (i.e., 12 with DGAT1 KK genotype and 12 with DGAT1 AA genotype) were fed 2 diets in a crossover design: a control diet and a linseed oil diet (LSO) with a difference of 22 g/kg of dry matter (DM) in fat content between the 2 diets. Both diets consisted of 40% corn silage, 30% grass silage, and 30% concentrates (DM basis). Apparent digestibility, lactation performance, N and energy balance, and CH4 emission were measured in climate respiration chambers, and rumen fluid samples were collected using the oral stomach tube technique. No linseed oil by DGAT1 interactions were observed for digestibility, milk production and composition, energy and N balance, CH4 and H2 emissions, and rumen volatile fatty acid concentrations. The DGAT1 KK genotype was associated with a lower proportion of polyunsaturated fatty acids in milk fat, and with a higher milk fat and protein content, and proportion of saturated fatty acids in milk fat compared with the DGAT1 AA genotype, whereas the fat- and protein-corrected milk yield was unaffected by DGAT1. Also, DGAT1 did not affect nutrient digestibility, CH4 or H2 emission, ruminal fermentation or ruminal archaeal and bacterial concentrations. Rumen bacterial and archaeal composition was also unaffected in terms of the whole community, whereas at the genus level the relative abundances of some bacterial genera were found to be affected by DGAT1. The DGAT1 KK genotype was associated with a lower metabolizability (i.e., ratio of metabolizable to gross energy intake), and with a tendency for a lower milk N efficiency compared with the DGAT1 AA genotype. The LSO diet tended to decrease CH4 production (g/d) by 8%, and significantly decreased CH4 yield (g/kg of DM intake) by 6% and CH4 intensity (g/kg of fat- and protein-corrected milk) by 11%, but did not affect H2 emission. The LSO diet also decreased ruminal acetate molar proportion, the acetate to propionate ratio, and the archaea to bacteria ratio, whereas ruminal propionate molar proportion and milk N efficiency increased. Ruminal bacterial and archaeal composition tended to be affected by diet in terms of the whole community, with several bacterial genera found to be significantly affected by diet. These results indicate that DGAT1 does not affect enteric CH4 emission and production pathways, but that it does affect traits other than lactation characteristics, including metabolizability, N efficiency, and the relative abundance of Bifidobacterium. Additionally, linseed oil reduces CH4 emission independent of DGAT1 and affects the rumen microbiota and its fermentative activity.
The infant gut microbiota affects childhood health. This pioneer microbiota may be vulnerable to antibiotic exposures, but could be supported by prebiotic oligosaccharides found in breast milk and ...some infant formulas. We sought to characterize the effects of several exposures on the neonatal gut microbiota, including human milk oligosaccharides (HMOs), galacto-oligosaccharides (GOS), and infant/maternal antimicrobial exposures. We profiled the stool microbiota of 1023 one-month-old infants from the KOALA Birth Cohort using 16S rRNA gene amplicon sequencing. We quantified 15 HMOs in breast milk from the mothers of 220 infants, using high-performance liquid chromatography-mass spectrometry. Both breastfeeding and antibiotic exposure decreased gut microbial diversity, but each was associated with contrasting shifts in microbiota composition. Other factors associated with microbiota composition included C-section, homebirth, siblings, and exposure to animals. Neither infant exposure to oral antifungals nor maternal exposure to antibiotics during pregnancy were associated with infant microbiota composition. Four distinct groups of breast milk HMO compositions were evident, corresponding to maternal Secretor status and Lewis group combinations defined by the presence/absence of certain fucosylated HMOs. However, we found the strongest evidence for microbiota composition associations between two non-fucosylated HMOs: 6'-sialyllactose (6'-SL) and lacto-N-hexaose (LNH). Among 111 exclusively formula-fed infants, the GOS-supplemented formula was associated with a lower relative abundance of Clostridium perfringens. In conclusion, the gut microbiota is sensitive to some prebiotic and antibiotic exposures during early infancy and understanding their effects could inform future strategies for safeguarding a health-promoting infant gut microbiota.
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