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BACKGROUND: The substantial risk for respiratory and invasive infections with Streptococcus pneumoniae (Spn) among people with HIV-1 (PWH) begins with asymptomatic colonization. The frequency of Spn colonization among U.S. adults with and without HIV-1 infection is not well-characterized in the conjugate vaccine era. METHODS: We determined Spn colonization frequency by culture and specific lytA gene QPCR and microbiota profile by 16S rRNA gene sequencing in nasopharyngeal (NP) and oropharyngeal (OP) DNA from 138 PWH and 93 control adults and associated clinical characteristics. RESULTS: The frequencies of Spn colonization among PWH and controls did not differ (11.6% vs 8.6%, respectively; p=0.46) using combined results of culture and PCR, independent of vaccination or behavioral risks. PWH showed altered microbiota composition (i.e., beta-diversity. NP: p=0.0028, OP: p=0.0098), decreased alpha-diversity (NP: p=0.024, OP: p=0.0045), and differences in the relative abundance of multiple bacterial taxa. Spn colonization was associated with altered beta-diversity in the NP (p=0.011), but not OP (p=0.21). CONCLUSIONS: Despite widespread conjugate vaccine and antiretroviral use, frequencies of Spn colonization among PWH and controls are currently consistent with those reported in the pre-conjugate era. The persistently increased risk of pneumococcal disease despite ART may relate to behavioral and immunologic variables other than colonization.
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Nonalcoholic steatohepatitis (NASH) is the most common chronic liver disease in the US, partly due to the increasing incidence of metabolic syndrome, obesity, and type 2 diabetes. The roles of bile acids and their receptors, such as the nuclear receptor farnesoid X receptor (FXR) and the G protein-coupled receptor TGR5, on the development of NASH are not fully clear. C57BL/6J male mice fed a Western diet (WD) develop characteristics of NASH, allowing determination of the effects of FXR and TGR5 agonists on this disease. Here we show that the FXR-TGR5 dual agonist INT-767 prevents progression of WD-induced hepatic steatosis, inflammation, and fibrosis, as determined by histological and biochemical assays and novel label-free microscopy imaging techniques, including third harmonic generation, second harmonic generation, and fluorescence lifetime imaging microscopy. Furthermore, we show INT-767 decreases liver fatty acid synthesis and fatty acid and cholesterol uptake, as well as liver inflammation. INT-767 markedly changed bile acid composition in the liver and intestine, leading to notable decreases in the hydrophobicity index of bile acids, known to limit cholesterol and lipid absorption. In addition, INT-767 upregulated expression of liver p-AMPK, SIRT1, PGC-1α, and SIRT3, which are master regulators of mitochondrial function. Finally, we found INT-767 treatment reduced WD-induced dysbiosis of gut microbiota. Interestingly, the effects of INT-767 in attenuating NASH were absent in FXR-null mice, but still present in TGR5-null mice. Our findings support treatment and prevention protocols with the dual FXR-TGR5 agonist INT-767 arrest progression of WD-induced NASH in mice mediated by FXR-dependent, TGR5-independent mechanisms.
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Diabetes Mellitus Tipo 2 , Enfermedad del Hígado Graso no Alcohólico , Animales , Masculino , Ratones , Ácidos y Sales Biliares , Colesterol/metabolismo , Diabetes Mellitus Tipo 2/complicaciones , Dieta Occidental , Ácidos Grasos , Fibrosis , Inflamación/complicaciones , Ratones Endogámicos C57BL , Ratones Noqueados , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Receptores Acoplados a Proteínas G/metabolismoRESUMEN
BACKGROUND: Tobramycin inhalation solution (TIS) and chronic azithromycin (AZ) have known clinical benefits for children with CF, likely due to antimicrobial and anti-inflammatory activity. The effects of chronic AZ in combination with TIS on the airway microbiome have not been extensively investigated. Oropharyngeal swab samples were collected in the OPTIMIZE multicenter, randomized, placebo-controlled trial examining the addition of AZ to TIS in 198 children with CF and early P. aeruginosa infection. Bacterial small subunit rRNA gene community profiles were determined. The effects of TIS and AZ were assessed on oropharyngeal microbial diversity and composition to uncover whether effects on the bacterial community may be a mechanism of action related to the observed changes in clinical outcomes. RESULTS: Substantial changes in bacterial communities (total bacterial load, diversity and relative abundance of specific taxa) were observed by week 3 of TIS treatment for both the AZ and placebo groups. On average, these shifts were due to changes in non-traditional CF taxa that were not sustained at the later study visits (weeks 13 and 26). Bacterial community measures did not differ between the AZ and placebo groups. CONCLUSIONS: This study provides further evidence that the mechanism for AZ's effect on clinical outcomes is not due solely to action on airway microbial composition.
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Fibrosis Quística , Microbiota , Infecciones por Pseudomonas , Humanos , Niño , Azitromicina/farmacología , Azitromicina/uso terapéutico , Infecciones por Pseudomonas/tratamiento farmacológico , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Fibrosis Quística/complicaciones , Fibrosis Quística/tratamiento farmacológico , Fibrosis Quística/microbiología , Administración por Inhalación , Pseudomonas aeruginosa/genética , Tobramicina/farmacología , Bacterias/genética , Microbiota/genéticaRESUMEN
BACKGROUND: Evidence regarding the effects of infant feeding type (exclusive breastfeeding compared with exclusive formula feeding) on the gut microbiota and how it impacts infant growth status is limited. OBJECTIVES: The primary objective was to compare gut microbiota by feeding type and characterize the associations between gut microbiota and infant growth status. METHODS: Stool samples from healthy, full-term infants (4-5 mo-old) who were either exclusively breastfed (BF) or exclusively formula-fed (FF) in Denver, CO, United States were collected, and fecal 16S ribosomal ribonucleic acid gene-based profiling was conducted. Length and weight were measured at the time of stool collection. Length-for-age z-score, weight-for-age z-scores (WAZ), and weight-for-length z-scores were calculated based on the World Health Organization standards. Associations between gut microbial taxa and anthropometric z-scores were assessed by Spearman's rank correlation test. RESULTS: A total of 115 infants (BF n = 54; FF n = 61) were included in this study. Feeding type (BF compared with FF) was the most significant tested variable on gut microbiota composition (P < 1 × 10-6), followed by mode of delivery and race. Significant differences were observed in α-diversity, ß-diversity, and relative abundances of individual taxa between BF and FF. BF infants had lower α-diversity than FF infants. Abundances of Bifidobacterium and Lactobacillus were greater in the breastfeeding group. FF infants had a higher relative abundance of unclassified Ruminococcaceae (P < 0.001), which was associated with a higher WAZ (P < 0.001) and length-for-age z-score (P < 0.01). Lactobacillus was inversely associated with WAZ (P < 0.05). CONCLUSIONS: Feeding type is the main driver of gut microbiota differences in young infants. The gut microbiota differences based on feeding type (exclusive breast- or formula feeding) were associated with observed differences in growth status. This trial was registered at clinicaltrials.gov as NCT02142647, NCT01693406, and NCT04137445.
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Lactancia Materna , Microbioma Gastrointestinal , Femenino , Humanos , Lactante , Leche Humana , Fórmulas Infantiles , Fenómenos Fisiológicos Nutricionales del Lactante , Heces/microbiologíaRESUMEN
BACKGROUND: Tobacco smoke exposure increases the risk and severity of lower respiratory tract infections in children, yet the mechanisms remain unclear. We hypothesized that tobacco smoke exposure would modify the lower airway microbiome. METHODS: Secondary analysis of a multicenter cohort of 362 children between ages 31 days and 18 years mechanically ventilated for >72 h. Tracheal aspirates from 298 patients, collected within 24 h of intubation, were evaluated via 16 S ribosomal RNA sequencing. Smoke exposure was determined by creatinine corrected urine cotinine levels ≥30 µg/g. RESULTS: Patients had a median age of 16 (IQR 568) months. The most common admission diagnosis was lower respiratory tract infection (53%). Seventy-four (20%) patients were smoke exposed and exhibited decreased richness and Shannon diversity. Smoke exposed children had higher relative abundances of Serratia spp., Moraxella spp., Haemophilus spp., and Staphylococcus aureus. Differences were most notable in patients with bacterial and viral respiratory infections. There were no differences in development of acute respiratory distress syndrome, days of mechanical ventilation, ventilator free days at 28 days, length of stay, or mortality. CONCLUSION: Among critically ill children requiring prolonged mechanical ventilation, tobacco smoke exposure is associated with decreased richness and Shannon diversity and change in microbial communities. IMPACT: Tobacco smoke exposure is associated with changes in the lower airways microbiome but is not associated with clinical outcomes among critically ill pediatric patients requiring prolonged mechanical ventilation. This study is among the first to evaluate the impact of tobacco smoke exposure on the lower airway microbiome in children. This research helps elucidate the relationship between tobacco smoke exposure and the lower airway microbiome and may provide a possible mechanism by which tobacco smoke exposure increases the risk for poor outcomes in children.
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Microbiota , Infecciones del Sistema Respiratorio , Contaminación por Humo de Tabaco , Humanos , Niño , Contaminación por Humo de Tabaco/efectos adversos , Enfermedad Crítica , Respiración Artificial/efectos adversos , Humo/efectos adversos , Nicotiana , CotininaRESUMEN
OBJECTIVE: The aim of the study was to determine the mucosal microbiota associated with eosinophilic esophagitis (EoE) and eosinophilic gastritis (EoG) in a geographically diverse cohort of patients compared to controls. METHODS: We conducted a prospective study of individuals with eosinophilic gastrointestinal disease (EGID) in the Consortium of Eosinophilic Gastrointestinal Disease Researchers, including pediatric and adult tertiary care centers. Eligible individuals had clinical data, mucosal biopsies, and stool collected. Total bacterial load was determined from mucosal biopsy samples by quantitative polymerase chain reaction (PCR). Community composition was determined by small subunit rRNA gene amplicons. RESULTS: One hundred thirty-nine mucosal biopsies were evaluated corresponding to 93 EoE, 17 EoG, and 29 control specimens (18 esophageal) from 10 sites across the United States. Dominant community members across disease activity differed significantly. When comparing EoE and EoG with controls, the dominant taxa in individuals with EGIDs was increased ( Streptococcus in esophagus; Prevotella in stomach). Specific taxa were associated with active disease for both EoE ( Streptococcus , Gemella ) and EoG ( Leptotrichia ), although highly individualized communities likely impacted statistical testing. Alpha diversity metrics were similar across groups, but with high variability among individuals. Stool analyses did not correlate with bacterial communities found in mucosal biopsy samples and was similar in patients and controls. CONCLUSIONS: Dominant community members ( Streptococcus for EoE, Prevotella for EoG) were different in the mucosal biopsies but not stool of individuals with EGIDs compared to controls; taxa associated with EGIDs were highly variable across individuals. Further study is needed to determine if therapeutic interventions contribute to the observed community differences.
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Esofagitis Eosinofílica , Microbiota , Adulto , Humanos , Niño , Esofagitis Eosinofílica/patología , Estudios ProspectivosRESUMEN
BACKGROUND: Otitis media (OM) susceptibility has significant heritability; however, the role of rare variants in OM is mostly unknown. Our goal is to identify novel rare variants that confer OM susceptibility. METHODS: We performed exome and Sanger sequencing of >1000 DNA samples from 551 multiethnic families with OM and unrelated individuals, RNA-sequencing and microbiome sequencing and analyses of swabs from the outer ear, middle ear, nasopharynx and oral cavity. We also examined protein localisation and gene expression in infected and healthy middle ear tissues. RESULTS: A large, intermarried pedigree that includes 81 OM-affected and 53 unaffected individuals cosegregates two known rare A2ML1 variants, a common FUT2 variant and a rare, novel pathogenic variant c.1682A>G (p.Glu561Gly) within SPINK5 (LOD=4.09). Carriage of the SPINK5 missense variant resulted in increased relative abundance of Microbacteriaceae in the middle ear, along with occurrence of Microbacteriaceae in the outer ear and oral cavity but not the nasopharynx. Eight additional novel SPINK5 variants were identified in 12 families and individuals with OM. A role for SPINK5 in OM susceptibility is further supported by lower RNA counts in variant carriers, strong SPINK5 localisation in outer ear skin, faint localisation to middle ear mucosa and eardrum and increased SPINK5 expression in human cholesteatoma. CONCLUSION: SPINK5 variants confer susceptibility to non-syndromic OM. These variants potentially contribute to middle ear pathology through breakdown of mucosal and epithelial barriers, immunodeficiency such as poor vaccination response, alteration of head and neck microbiota and facilitation of entry of opportunistic pathogens into the middle ear.
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Microbiota , Otitis Media/genética , Otitis Media/microbiología , Inhibidor de Serinpeptidasas Tipo Kazal-5/genética , Adulto , Animales , Bacterias/clasificación , Bacterias/genética , Niño , Susceptibilidad a Enfermedades/microbiología , Oído Externo/microbiología , Oído Medio/microbiología , Exoma , Femenino , Predisposición Genética a la Enfermedad , Humanos , Masculino , Ratones , Boca/microbiología , Nasofaringe/microbiología , Linaje , Análisis de Secuencia de ADN , Análisis de Secuencia de ARNRESUMEN
Nonalcoholic fatty liver disease is a rapidly rising problem in the 21st century and is a leading cause of chronic liver disease that can lead to end-stage liver diseases, including cirrhosis and hepatocellular cancer. Despite this rising epidemic, no pharmacological treatment has yet been established to treat this disease. The rapidly increasing prevalence of nonalcoholic fatty liver disease and its aggressive form, nonalcoholic steatohepatitis (NASH), requires novel therapeutic approaches to prevent disease progression. Alterations in microbiome dynamics and dysbiosis play an important role in liver disease and may represent targetable pathways to treat liver disorders. Improving microbiome properties or restoring normal bile acid metabolism may prevent or slow the progression of liver diseases such as NASH. Importantly, aberrant systemic circulation of bile acids can greatly disrupt metabolic homeostasis. Bile acid sequestrants are orally administered polymers that bind bile acids in the intestine, forming nonabsorbable complexes. Bile acid sequestrants interrupt intestinal reabsorption of bile acids, decreasing their circulating levels. We determined that treatment with the bile acid sequestrant sevelamer reversed the liver injury and prevented the progression of NASH, including steatosis, inflammation, and fibrosis in a Western diet-induced NASH mouse model. Metabolomics and microbiome analysis revealed that this beneficial effect is associated with changes in the microbiota population and bile acid composition, including reversing microbiota complexity in cecum by increasing Lactobacillus and decreased Desulfovibrio The net effect of these changes was improvement in liver function and markers of liver injury and the positive effects of reversal of insulin resistance.
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Ácidos y Sales Biliares/metabolismo , Dieta Occidental , Hígado/efectos de los fármacos , Enfermedad del Hígado Graso no Alcohólico/patología , Sevelamer/farmacología , Animales , Ácidos y Sales Biliares/química , Ciego/microbiología , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Colesterol/análisis , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Cadena alfa 1 del Colágeno Tipo I , Modelos Animales de Enfermedad , Heces/química , Microbioma Gastrointestinal/efectos de los fármacos , Lactobacillus/efectos de los fármacos , Metabolismo de los Lípidos/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/prevención & control , Sevelamer/química , Sevelamer/uso terapéutico , Índice de Severidad de la Enfermedad , Factor de Crecimiento Transformador beta/genética , Factor de Crecimiento Transformador beta/metabolismoRESUMEN
Non-secretor status due to homozygosity for the common FUT2 variant c.461G>A (p.Trp154∗) is associated with either risk for autoimmune diseases or protection against viral diarrhea and HIV. We determined the role of FUT2 in otitis media susceptibility by obtaining DNA samples from 609 multi-ethnic families and simplex case subjects with otitis media. Exome and Sanger sequencing, linkage analysis, and Fisher exact and transmission disequilibrium tests (TDT) were performed. The common FUT2 c.604C>T (p.Arg202∗) variant co-segregates with otitis media in a Filipino pedigree (LOD = 4.0). Additionally, a rare variant, c.412C>T (p.Arg138Cys), is associated with recurrent/chronic otitis media in European-American children (p = 1.2 × 10-5) and US trios (TDT p = 0.01). The c.461G>A (p.Trp154∗) variant was also over-transmitted in US trios (TDT p = 0.01) and was associated with shifts in middle ear microbiota composition (PERMANOVA p < 10-7) and increased biodiversity. When all missense and nonsense variants identified in multi-ethnic US trios with CADD > 20 were combined, FUT2 variants were over-transmitted in trios (TDT p = 0.001). Fut2 is transiently upregulated in mouse middle ear after inoculation with non-typeable Haemophilus influenzae. Four FUT2 variants-namely p.Ala104Val, p.Arg138Cys, p.Trp154∗, and p.Arg202∗-reduced A antigen in mutant-transfected COS-7 cells, while the nonsense variants also reduced FUT2 protein levels. Common and rare FUT2 variants confer susceptibility to otitis media, likely by modifying the middle ear microbiome through regulation of A antigen levels in epithelial cells. Our families demonstrate marked intra-familial genetic heterogeneity, suggesting that multiple combinations of common and rare variants plus environmental factors influence the individual otitis media phenotype as a complex trait.
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Fucosiltransferasas/genética , Variación Genética/genética , Otitis Media/genética , Animales , Células COS , Línea Celular , Chlorocebus aethiops , Oído Medio/microbiología , Exoma/genética , Femenino , Células HEK293 , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Microbiota/fisiología , Otitis Media/microbiología , Linaje , Galactósido 2-alfa-L-FucosiltransferasaRESUMEN
We sought to determine whether temporal changes in the lower airway microbiome are associated with ventilator-associated pneumonia (VAP) in children.Using a multicentre prospective study of children aged 31â days to 18â years requiring mechanical ventilation support for >72â h, daily tracheal aspirates were collected and analysed by sequencing of the 16S rRNA gene. VAP was assessed using 2008 Centers for Disease Control and Prevention paediatric criteria. The association between microbial factors and VAP was evaluated using joint longitudinal time-to-event modelling, matched case-control comparisons and unsupervised clustering.Out of 366 eligible subjects, 66 (15%) developed VAP at a median of 5 (interquartile range 3-5) days post intubation. At intubation, there was no difference in total bacterial load (TBL), but Shannon diversity and the relative abundance of Streptococcus, Lactobacillales and Prevotella were lower for VAP subjects versus non-VAP subjects. However, higher TBL on each sequential day was associated with a lower hazard (hazard ratio 0.39, 95% CI 0.23-0.64) for developing VAP, but sequential values of diversity were not associated with VAP. Similar findings were observed from the matched analysis and unsupervised clustering. The most common dominant VAP pathogens included Prevotella species (19%), Pseudomonas aeruginosa (14%) and Streptococcus mitis/pneumoniae (10%). Mycoplasma and Ureaplasma were also identified as dominant organisms in several subjects.In mechanically ventilated children, changes over time in microbial factors were marginally associated with VAP risk, although these changes were not suitable for predicting VAP in individual patients. These findings suggest that focusing exclusively on pathogen burden may not adequately inform VAP diagnosis.
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Microbiota , Neumonía Asociada al Ventilador , Niño , Humanos , Unidades de Cuidados Intensivos , Neumonía Asociada al Ventilador/epidemiología , Estudios Prospectivos , ARN Ribosómico 16S/genéticaRESUMEN
The presence of methane and other hydrocarbons in domestic-use groundwater aquifers poses significant environmental and human health concerns. Isotopic measurements are often relied upon as indicators of groundwater aquifer contamination with methane. While these parameters are used to infer microbial metabolisms, there is growing evidence that isotopes present an incomplete picture of subsurface microbial processes. This study examined the relationships between microbiology and chemistry in groundwater wells located in the Denver-Julesburg Basin of Colorado, a rapidly urbanizing area with active oil and gas development. A primary goal was to determine if microbial data can reliably indicate the quantities and sources of groundwater methane. Comprehensive chemical and molecular analyses were performed on 39 groundwater well samples from five aquifers. Elevated methane concentrations were found in only one aquifer, and both isotopic and microbial data support a microbial origin. Microbial parameters had similar explanatory power as chemical parameters for predicting sample methane concentrations. Furthermore, a subset of samples with unique microbiology corresponded with unique chemical signatures that may be useful indicators of methane gas migration, potentially from nearby coal seams interacting with the aquifer. Microbial data may allow for more accurate determination of groundwater contamination and improved long-term water quality monitoring compared solely to isotopic and chemical data in areas with microbial methane.
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Agua Subterránea , Contaminantes Químicos del Agua , Colorado , Monitoreo del Ambiente , Humanos , Metano/análisis , Yacimiento de Petróleo y Gas , Contaminantes Químicos del Agua/análisisRESUMEN
BACKGROUND: Acid blockade is commonly prescribed in patients with cystic fibrosis (CF). Growing concerns, however, exist about its possible role in the pathophysiology of pulmonary infections. We aimed to investigate if acid blockade alters esophageal and respiratory microbiota leading to dysbiosis and inflammation. METHODS: We performed a cross sectional study of children with CF who were either prescribed acid blockade or not. Samples from the gastrointestinal and respiratory tracts were obtained and microbiome analyzed. Mixed effect models were used to compare outcomes between cohorts and across sampling sites. A random subject intercept was included to account for the multiple sampling sites per individual. RESULTS: A cohort of 25 individuals, 44% girls with median age of 13.8 years [IQR 11.2--14.8] were enrolled. Alpha diversity, total bacterial load, and beta diversity were similar across anatomic compartments, across the upper gastrointestinal tract, and in respiratory samples. Similar alpha diversity, total bacterial load, and beta diversity results were also observed when comparing individuals on versus those off acid blockade. IL-8 was elevated in the distal versus proximal esophagus in the whole cohort (Pâ<â0.01). IL-8 concentrations were similar in the distal esophagus in patients on and off acid blockade, but significantly greater in the proximal esophagus of subjects on treatment (Pâ<â0.01). CONCLUSIONS: On the basis of these data, acid blockade use does not appear to influence the microbiome of the aerodigestive tract in children with cystic fibrosis suggesting a complex interplay between these medications and the bacterial composition of the esophagus and lung.
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Fibrosis Quística , Microbiota , Adolescente , Bacterias , Niño , Estudios Transversales , Fibrosis Quística/tratamiento farmacológico , Disbiosis , Femenino , Humanos , MasculinoRESUMEN
Our objectives were to characterise the microbiota in cystic fibrosis (CF) bronchoalveolar lavage fluid (BALF), and determine its relationship to inflammation and disease status.BALF from paediatric and adult CF patients and paediatric disease controls undergoing clinically indicated bronchoscopy was analysed for total bacterial load and for microbiota by 16S rDNA sequencing.We examined 191 BALF samples (146 CF and 45 disease controls) from 13 CF centres. In CF patients aged <2â years, nontraditional taxa (e.gStreptococcus, Prevotella and Veillonella) constituted â¼50% of the microbiota, whereas in CF patients aged ≥6â years, traditional CF taxa (e.gPseudomonas, Staphylococcus and Stenotrophomonas) predominated. Sequencing detected a dominant taxon not traditionally associated with CF (e.gStreptococcus or Prevotella) in 20% of CF BALF and identified bacteria in 24% of culture-negative BALF. Microbial diversity and relative abundance of Streptococcus, Prevotella and Veillonella were inversely associated with airway inflammation. Microbiota communities were distinct in CF compared with disease controls, but did not differ based on pulmonary exacerbation status in CF.The CF microbiota detected in BALF differs with age. In CF patients aged <2â years, Streptococcus predominates, whereas classic CF pathogens predominate in most older children and adults.
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Factores de Edad , Fibrosis Quística/microbiología , Inflamación/complicaciones , Pulmón/microbiología , Microbiota , Adolescente , Adulto , Líquido del Lavado Bronquioalveolar/microbiología , Estudios de Casos y Controles , Niño , Preescolar , ADN Bacteriano/análisis , Progresión de la Enfermedad , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Análisis Multivariante , Análisis de Regresión , Esputo/microbiología , Adulto JovenRESUMEN
The two municipal drinking water systems of New Orleans, LA, U.S.A. were sampled to compare the microbiology of independent systems that treat the same surface water from the Mississippi River. To better understand temporal trends and sources of microbiology delivered to taps, these treatment plants and distribution systems were subjected to source-to-tap sampling over four years. Both plants employ traditional treatment by chloramination, applied during or after settling, followed by filtration before distribution in a warm, low water age system. Longitudinal samples indicated microbiology to have stability both spatially and temporally, and between treatment plants and distribution systems. Disinfection had the greatest impact on microbial composition, which was further refined by filtration and influenced by distribution and premise plumbing. Actinobacteria spp. exhibited trends with treatment. In particular, Mycobacterium spp., very low in finished waters, occurred idiosyncratically at high levels in some tap waters, indicating distribution and/or premise plumbing as main contributors of mycobacteria. Legionella spp., another genus containing potential opportunistic pathogens, also occurred ubiquitously. Source water microbiology was most divergent from tap water, and each step of treatment brought samples more closely similar to tap waters.
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Legionella , Microbiología del Agua , Desinfección , Agua Potable/microbiología , Nueva Orleans , Purificación del Agua , Abastecimiento de AguaRESUMEN
PURPOSE: To investigate the presence and microbiology of bacterial biofilms on Jones tubes (JTs) by direct visualization with scanning electron microscopy and polymerase chain reaction (PCR) of representative JTs, and to correlate these findings with inflammation and/or infection related to the JT. METHODS: In this study, prospective case series were performed. JTs were recovered from consecutive patients presenting to clinic for routine cleaning or recurrent irritation/infection. Four tubes were processed for scanning electron microscopy alone to visualize evidence of biofilms. Two tubes underwent PCR alone for bacterial quantification. One tube was divided in half and sent for scanning electron microscopy and PCR. Symptoms related to the JTs were recorded at the time of recovery. RESULTS: Seven tubes were obtained. Five underwent SEM, and 3 out of 5 showed evidence of biofilms (60%). Two of the 3 biofilms demonstrated cocci and the third revealed rods. Three tubes underwent PCR. The predominant bacteria identified were Pseudomonadales (39%), Pseudomonas (16%), and Staphylococcus (14%). Three of the 7 patients (43%) reported irritation and discharge at presentation. Two symptomatic patients, whose tubes were imaged only, revealed biofilms. The third symptomatic patient's tube underwent PCR only, showing predominantly Staphylococcus (56%) and Haemophilus (36%) species. Two of the 4 asymptomatic patients also showed biofilms. All symptomatic patients improved rapidly after tube exchange and steroid antibiotic drops. CONCLUSIONS: Bacterial biofilms were variably present on JTs, and did not always correlate with patients' symptoms. Nevertheless, routine JT cleaning is recommended to treat and possibly prevent inflammation caused by biofilms.
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Biopelículas/crecimiento & desarrollo , Dacriocistorrinostomía/instrumentación , Adulto , Anciano , Contaminación de Equipos , Femenino , Humanos , Masculino , Microscopía Electrónica de Rastreo , Persona de Mediana Edad , Estudios ProspectivosRESUMEN
BACKGROUND: Iron therapy induces inflammation, which could decrease iron absorption. Increased exposure of iron in the gut could also alter microbiome file. Providing antioxidants such as vitamin E with iron therapy has been associated with reduced oxidative potential. OBJECTIVE: The aim of the present study was to test the efficacy of adding vitamin E to therapeutic iron therapy on iron repletion, inflammation markers, and gut microbiome in iron-deficient infants and toddlers. DESIGN: This was a randomized, double-blind, control trial in which infants and toddlers (Denver, CO metro area) who were at risk of iron deficiency were screened. Eligible participants were randomized to receive iron therapy (6 mgâ·âkgâ·âday) plus placebo (nâ=â22) or iron (6 mgâ·âkgâ·âday) and vitamin E (18 mg/day, nâ=â14) for 8 weeks. Iron and inflammation status, and gut microbiome (16S sequencing) were analyzed in all participants before and after the treatment. RESULTS: After 8 weeks of treatment, average serum ferritin level returned to normal for both ironâ+âplacebo and ironâ+âvitamin E groups at 33.3â±â20.2 and 33.5â±â21.5 µg/L, respectively. Serum vitamin E concentration increased in ironâ+âvitamin E group. No change over time was observed regarding serum interleukin-4, tumor necrosis factor-α, or fecal calprotectin. The relative abundance of the genus Roseburia (phylum Firmicutes), a butyrate producer, increased in the Feâ+âE group (Δ1.3%, Pâ<â0.01). Also at the genus level, the genus Escherichia decreased by 1.2% on average among all participants (effect of time Pâ=â0.01). CONCLUSIONS: Using a therapeutic iron dose of 6 mgâ·âkgâ·âday is effective in treating iron deficiency during an 8-week period, without inducing persistent inflammatory response. Changes of the gut microbiome raised the possibility that antioxidant therapy in conjunction with therapeutic iron supplementation could potentially improve microbial community profiles in the intestinal tract.
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Anemia Ferropénica/tratamiento farmacológico , Antioxidantes/uso terapéutico , Microbioma Gastrointestinal , Hierro/administración & dosificación , Vitamina E/administración & dosificación , Anemia Ferropénica/microbiología , Preescolar , Suplementos Dietéticos , Método Doble Ciego , Femenino , Ferritinas/sangre , Humanos , Lactante , Masculino , ARN Ribosómico 16S/genética , Vitamina E/sangreRESUMEN
OBJECTIVES: Bacterial colonization and succession of the human intestine shape development of immune function and risk for allergic disease, yet these processes remain poorly understood. We investigated the relations between delivery mode, initial bacterial inoculation of the infant oropharynx (OP), and intestinal colonization. METHODS: We prospectively collected maternal rectal and vaginal swabs, infant OP aspirates, and infant stool from 23 healthy mother/infant pairs delivering by cesarean (CS) or vaginal delivery (VD) in an academic hospital. Bacterial abundance (16S rRNA sequencing) and community similarity between samples were compared by delivery mode. Shotgun DNA metagenomic sequencing of infant stool was performed. RESULTS: VD infants had higher abundance of Firmicutes (mainly lactobacilli) in OP aspirates whereas CS OP aspirates were enriched in skin bacteria. OP aspirates were more similar to maternal vaginal and rectal microbiomes in VD compared with CS. Bacteroidetes were more abundant through 6 weeks in stool of VD infants. Infant fecal microbiomes in both delivery groups did not resemble maternal rectal or vaginal microbiomes. Differences in fecal bacterial gene potential between CS and VD at 6 weeks clustered in metabolic pathways and were mediated by abundance of Proteobacteria and Bacteroidetes. CONCLUSIONS: CS infants exhibited different microbiota in the oral inoculum, a chaotic pattern of bacterial succession, and a persistent deficit of intestinal Bacteroidetes. Pioneer OP bacteria transferred from maternal vaginal and intestinal communities were not prominent constituents of the early infant fecal microbiome. Oral inoculation at birth may impact the intestinal microenvironment, thereby modulating early succession of intestinal bacteria.
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Parto Obstétrico/métodos , Heces/microbiología , Intestinos/microbiología , Microbiota , Faringe/microbiología , Adulto , Parto Obstétrico/efectos adversos , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Embarazo , Estudios Prospectivos , Recto/microbiología , Análisis de Secuencia de ADN , Piel/microbiología , Vagina/microbiologíaRESUMEN
BACKGROUND: Chronic rhinosinusitis (CRS) is a prevalent multifactorial disease process in which bacteria are believed to play a role in the propagation of inflammation. Multiple subtypes of CRS have been described based on clinical and pathologic features, but a detailed examination of the sinus microbiota in patients with CRS and its clinical subtypes has yet to be performed. OBJECTIVE: We sought to examine the resident microbiota of CRS subtypes and determine whether bacterial diversity is a predictor of disease outcomes. METHODS: Sinus swabs from patients with CRS and healthy subjects collected during endoscopic sinus surgery were analyzed by means of molecular phylogenetic analysis of 16S rDNA pyrosequences. RESULTS: Fifty-six patients with CRS and 26 control subjects were studied. Biodiversity was similar between the CRS and control groups. Among the CRS subtypes examined, only 2 conditions (presence of purulence and comorbid condition of asthma) were associated with significant alterations in microbial community composition. In 27 patients with CRS who were followed postoperatively, those with better outcomes had more diverse bacterial communities present at the time of surgery, along with higher relative abundances of Actinobacteria. CONCLUSION: Analysis of microbiota in a large cohort reveals that particular CRS phenotypes (asthma and purulence) are characterized by distinct compositions of resident bacterial communities. We found that bacterial diversity and composition are predictors of surgical outcome, promoting the concept of community ecology in patients with CRS.
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Asma/cirugía , Bacterias/clasificación , Genes de ARNr , Senos Paranasales/cirugía , Rinitis/cirugía , Sinusitis/cirugía , Corticoesteroides/uso terapéutico , Adulto , Antibacterianos/uso terapéutico , Antiinflamatorios/uso terapéutico , Asma/complicaciones , Asma/tratamiento farmacológico , Asma/microbiología , Bacterias/efectos de los fármacos , Bacterias/genética , Biodiversidad , Estudios de Casos y Controles , Enfermedad Crónica , Estudios Transversales , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Microbiota/efectos de los fármacos , Microbiota/genética , Persona de Mediana Edad , Senos Paranasales/efectos de los fármacos , Senos Paranasales/inmunología , Senos Paranasales/microbiología , Fenotipo , ARN Ribosómico 16S/genética , Rinitis/complicaciones , Rinitis/tratamiento farmacológico , Rinitis/microbiología , Sinusitis/complicaciones , Sinusitis/tratamiento farmacológico , Sinusitis/microbiología , Resultado del TratamientoRESUMEN
Studies of the human microbiome, and microbial community ecology in general, have blossomed of late and are now a burgeoning source of exciting research findings. Along with the advent of next-generation sequencing platforms, which have dramatically increased the scope of microbiome-related projects, several high-performance sequence analysis pipelines (e.g. QIIME, MOTHUR, VAMPS) are now available to investigators for microbiome analysis. The subject of our manuscript, the graphical user interface-based Explicet software package, fills a previously unmet need for a robust, yet intuitive means of integrating the outputs of the software pipelines with user-specified metadata and then visualizing the combined data.
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Gráficos por Computador , Sistemas de Administración de Bases de Datos , Microbiota/genética , Programas Informáticos , Interfaz Usuario-Computador , Biología Computacional , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Metagenoma , Análisis de Secuencia de ADNRESUMEN
The microbial communities associated with deteriorating concrete corrosion fronts were characterized in 35 samples taken from wastewater collection and treatment systems in ten utilities. Bacterial communities were described using Illumina MiSeq sequencing of the V1V2 region of the small subunit ribosomal ribonucleic acid (SSU-rRNA) gene recovered from fresh corrosion products. Headspace gas concentrations (hydrogen sulfide, carbon dioxide, and methane), pore water pH, moisture content, and select mineralogy were tested for correlation to community outcomes and corrosion extent using pairwise linear regressions and canonical correspondence analysis. Corroding concrete was most commonly characterized by moisture contents greater than 10%, pore water pH below one, and limited richness (<10 taxa). Bacterial community composition was not correlated to geographic location when considered independently from other environmental factors. Corrosion was most severe in sites with high levels of hydrogen sulfide (>100 ppm) and carbon dioxide (>1%) gases, conditions which also were associated with low diversity biofilms dominated by members of the acidophilic sulfur-oxidizer genus Acidithiobacillus.