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Respiratory viruses cause airway inflammation, resulting in epithelial injury and repair. miRNAs, including miR-149-5p, regulate different pathological conditions. We aimed to determine how miR-149-5p functions in regulating pro-inflammatory IL-6 and p63, key regulators of airway epithelial wound repair, in response to viral proteins in bronchial (BEAS-2B) and alveolar (A549) epithelial cells. BEAS-2B or A549 cells were incubated with poly (I:C, 0.5 µg/mL) for 48 h or SARS-CoV-2 spike protein-1 or 2 subunit (S1 or S2, 1 µg/mL) for 24 h. miR-149-5p was suppressed in BEAS-2B challenged with poly (I:C), correlating with IL-6 and p63 upregulation. miR-149-5p was down-regulated in A549 stimulated with poly (I:C); IL-6 expression increased, but p63 protein levels were undetectable. miR-149-5p remained unchanged in cells exposed to S1 or S2, while S1 transfection increased IL-6 expression in BEAS-2B cells. Ectopic over-expression of miR-149-5p in BEAS-2B cells suppressed IL-6 and p63 mRNA levels and inhibited poly (I:C)-induced IL-6 and p63 mRNA expressions. miR-149-5p directly suppressed IL-6 mRNA in BEAS-2B cells. Hence, BEAS-2B cells respond differently to poly (I:C), S1 or S2 compared to A549 cells. Thus, miR-149-5p dysregulation may be involved in poly (I:C)-stimulated but not S1- or S2-stimulated increased IL-6 production and p63 expression in BEAS-2B cells.
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Células Epiteliales , Interleucina-6 , MicroARNs , Poli I-C , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Interleucina-6/metabolismo , Células A549 , Células Epiteliales/metabolismo , Células Epiteliales/efectos de los fármacos , Células Epiteliales/virología , Poli I-C/farmacología , SARS-CoV-2 , COVID-19/metabolismo , COVID-19/virología , Proteínas Supresoras de Tumor/metabolismo , Proteínas Supresoras de Tumor/genética , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Regulación de la Expresión Génica/efectos de los fármacosRESUMEN
Background: Human identification and kinship testing in forensic science rely on Short Tandem Repeat (STR) multiplex kits, typically containing loci recommended by standard sets. However, complementary kits with additional STR loci can be valuable in complex cases. Allele frequency databases specific to the population are essential for accurate forensic analysis.Aim: This study aimed to generate allele frequencies and population genetic data for 44 autosomal STR loci from SureID® PanGlobal and 27comp kits in English and Irish populations for forensic casework, human identification, and kinship testing.Subjects and methods: Buccal swab samples from 645 White Caucasians (365 English, 280 Irish) were collected. DNA was extracted and amplified using the mentioned kits. Quality control, statistical analysis, and genetic distance calculations were performed.Results: Both kits demonstrated robustness with no significant deviations from Hardy-Weinberg Equilibrium (HWE). Variant alleles and minor discordances between kits were observed. Syntenic STR pairs were identified but showed no significant linkage. A close genetic relationship was found between English and Irish populations, allowing for combined databases.Conclusions: The SureID® PanGlobal and 27comp kits showed high discriminatory power and reliability in the English and Irish populations. Care is needed when handling variant alleles, discordances, and syntenic loci. Combining data from both populations is feasible for a comprehensive database. Further studies are required to explore their effectiveness in diverse populations.
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ADN , Genética de Población , Humanos , Reproducibilidad de los Resultados , Frecuencia de los Genes , ADN/genética , Repeticiones de Microsatélite/genética , Variación GenéticaRESUMEN
OBJECTIVE: To determine the impact of supplemental bovine lactoferrin on the gut microbiome and metabolome of preterm infants. DESIGN: Cohort study nested within a randomised controlled trial (RCT). Infants across different trial arms were matched on several clinical variables. Bacteria and metabolite compositions of longitudinal stool and urine samples were analysed to investigate the impact of lactoferrin supplementation. SETTING: Thirteen UK hospitals participating in a RCT of lactoferrin. PATIENTS: 479 infants born <32 weeks' gestation between June 2016 and September 2017. RESULTS: 10 990 stool and 22 341 urine samples were collected. Analyses of gut microbiome (1304 stools, 201 infants), metabolites (171 stools, 83 infants; 225 urines, 90 infants) and volatile organic compounds (314 stools, 117 infants) were performed. Gut microbiome Shannon diversity at 34 weeks corrected age was not significantly different between infants in the lactoferrin (mean=1.24) or placebo (mean=1.06) groups (p=0.11). Lactoferrin receipt explained less than 1% variance in microbiome compositions between groups. Metabolomic analysis identified six discriminative features between trial groups. Hospital site (16%) and postnatal age (6%) explained the greatest variation in microbiome composition. CONCLUSIONS: This multiomic study identified minimal impacts of lactoferrin but much larger impacts of hospital site and postnatal age. This may be due to the specific lactoferrin product used, but more likely supports the findings of the RCT in which this study was nested, which showed no impact of lactoferrin on reducing rates of sepsis. Multisite mechanistic studies nested within RCTs are feasible and help inform trial interpretation and future trial design.
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Lactoferrina , Sepsis , Recién Nacido , Lactante , Humanos , Nutrición Enteral , Recien Nacido Prematuro , Edad GestacionalRESUMEN
A differentiated air-liquid interface model shows that the airway epithelium plays a key role in response to respiratory viral infections in people with asthma https://bit.ly/3yDgiX1.
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Studies of microbiota reveal inter-relationships between the microbiomes of the gut and lungs. This relationship may influence the progression of lung disease, particularly in patients with cystic fibrosis (CF), who often experience extraoesophageal reflux (EOR). Despite identifying this relationship, it is not well characterised. Our hypothesis is that the gastric and lung microbiomes in CF are related, with the potential for aerodigestive pathophysiology. We evaluated gastric and sputum bacterial communities by culture and 16S rRNA gene sequencing in 13 CF patients. Impacts of varying levels of bile acids, pepsin and pH on patient isolates of Pseudomonas aeruginosa (Pa) were evaluated. Clonally related strains of Pa and NTM were identified in gastric and sputum samples from patients with symptoms of EOR. Bacterial diversity was more pronounced in sputa compared to gastric juice. Gastric and lung bile and pepsin levels were associated with Pa biofilm formation. Analysis of the aerodigestive microbiomes of CF patients with negative sputa indicates that the gut can be a reservoir of Pa and NTM. This combined with the CF patient's symptoms of reflux and potential aspiration, highlights the possibility of communication between microorganisms of the gut and the lungs. This phenomenon merits further research.
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Fibrosis Quística , Reflujo Gastroesofágico , Microbiota , Bacterias , Bilis , Fibrosis Quística/microbiología , Jugo Gástrico/microbiología , Reflujo Gastroesofágico/complicaciones , Humanos , Pulmón/microbiología , Microbiota/genética , Pepsina A , Pseudomonas aeruginosa/genética , ARN Ribosómico 16S/genética , Esputo/microbiologíaRESUMEN
Formalin-Fixed Paraffin-Embedded (FFPE) tissues are routinely collected, archived, and used for clinical diagnosis, including maternal and neonatal health. Applying FFPE samples to microbiota research would be beneficial to reduce preparation, storage and costs associated with limited available frozen samples. This research aims to understand if FFPE fetal membrane samples are comparable to frozen tissues, which are the current gold standard for DNA microbiota analysis. Extracted DNA from nine matched paired patients were sequenced by Illumina sequencing of the V4 16S rRNA gene region. This included duplicate frozen amnion and chorion fetal membrane rolls or FFPE combined amniochorionic samples. Negative controls of surrounding wax blocks and DNA extraction reagents were processed alongside samples using identical methods. DNA quality and quantity was assessed by NanoDrop, agarose gel electrophoresis and Bioanalyzer. Decontam and SourceTracker were integrated into microbiota analysis to identify the presence of contaminating sources. The bacterial profile and nine genera differed between FFPE and frozen fetal membranes. There were no differences in bacterial profiles between FFPE samples and corresponding wax negative controls, with 49% of bacteria in FFPE fetal membrane samples matched to the source origin of paraffin wax, and 40% originating from DNA extraction reagent sources. FFPE samples displayed high fragmentation and low quantity of extracted DNA compared to frozen samples. The microbiota of FFPE fetal membrane samples is influenced by processing methods, with the inability to differentiate between the microbiota of the tissue sample and the surrounding wax block. Illumina sequencing results of FFPE and frozen fetal membrane samples should not be compared using the methods employed here. Variation could be influenced by limitations including storage time, DNA extraction and purification methods. To utilise FFPE fetal membrane samples in microbiota research then contamination prevention and detection methods must be included into optimised and standardised protocols, with recommendations presented here.
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Formaldehído , Microbiota , Bacterias , ADN , Membranas Extraembrionarias , Humanos , Recién Nacido , Microbiota/genética , Adhesión en Parafina/métodos , ARN Ribosómico 16S/genética , Fijación del Tejido/métodosRESUMEN
Given the increase in resistance to antibacterial agents, there is an urgent need for the development of new agents with novel modes of action. As an interim solution, it is also prudent to reinvestigate old or abandoned antibacterial compounds to assess their efficacy in the context of widespread resistance to conventional agents. In the 1970s, much work was performed on the development of peptide mimetics, exemplified by the phosphonopeptide, alafosfalin. We investigated the activity of alafosfalin, di-alanyl fosfalin and ß-chloro-L-alanyl-ß-chloro-L-alanine against 297 bacterial isolates, including carbapenemase-producing Enterobacterales (CPE) (n = 128), methicillin-resistant Staphylococcus aureus (MRSA) (n = 37) and glycopeptide-resistant enterococci (GRE) (n = 43). The interaction of alafosfalin with meropenem was also examined against 20 isolates of CPE. The MIC50 and MIC90 of alafosfalin for CPE were 1 mg/L and 4 mg/L, respectively and alafosfalin acted synergistically when combined with meropenem against 16 of 20 isolates of CPE. Di-alanyl fosfalin showed potent activity against glycopeptide-resistant isolates of Enterococcus faecalis (MIC90; 0.5 mg/L) and Enterococcus faecium (MIC90; 2 mg/L). Alafosfalin was only moderately active against MRSA (MIC90; 8 mg/L), whereas ß-chloro-L-alanyl-ß-chloro-L-alanine was slightly more active (MIC90; 4 mg/L). This study shows that phosphonopeptides, including alafosfalin, may have a therapeutic role to play in an era of increasing antibacterial resistance.
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Antibacterianos , Enterococcus faecalis/crecimiento & desarrollo , Enterococcus faecium/crecimiento & desarrollo , Staphylococcus aureus Resistente a Meticilina/crecimiento & desarrollo , Péptidos , Fosfoproteínas , Antibacterianos/química , Antibacterianos/farmacología , Pruebas de Sensibilidad Microbiana , Péptidos/química , Péptidos/farmacología , Fosfoproteínas/química , Fosfoproteínas/farmacologíaRESUMEN
INTRODUCTION: It is widely debated whether fetal membranes possess a genuine microbiome, and if bacterial presence and load is linked to inflammation. Chorioamnionitis is an inflammation of the fetal membranes. This research focussed on inflammatory diagnosed histological chorioamnionitis (HCA) and aimed to determine whether the bacterial load in fetal membranes correlates to inflammatory response, including histological staging and inflammatory markers in HCA. METHODS: Fetal membrane samples were collected from patients with preterm spontaneous labour and histologically phenotyped chorioamnionitis (HCA; n = 12), or preterm (n = 6) and term labour without HCA (n = 6). The bacterial profile of fetal membranes was analysed by sequencing the V4 region of the 16S rRNA gene. Bacterial load was determined using qPCR copy number/mg of tissue. The association between bacterial load and bacterial profile composition was assessed using correlation analysis. RESULTS: Bacterial load was significantly greater within HCA amnion (p = 0.002) and chorion (p = 0.042), compared to preterm birth without HCA. Increased bacterial load was positively correlated with increased histological staging (p = 0.001) and the expression of five inflammatory markers; IL8, TLR1, TLR2, LY96 and IRAK2 (p=<0.050). Bacterial profiles were significantly different between membranes with and without HCA in amnion (p = 0.012) and chorion (p = 0.001), but no differences between specific genera were detected. DISCUSSION: Inflammatory HCA is associated with infection and increased bacterial load in a dose response relationship. Bacterial load is positively correlated with HCA severity and the TLR signalling pathway. Further research should investigate the bacterial load threshold required to generate an inflammatory response in HCA.
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Corioamnionitis/microbiología , Membranas Extraembrionarias/microbiología , Microbiota/fisiología , Adulto , Carga Bacteriana , Femenino , Edad Gestacional , Humanos , Embarazo , Estudios RetrospectivosAsunto(s)
Enterocolitis Necrotizante , Microbioma Gastrointestinal , Sepsis , Humanos , Lactante , Recién Nacido , Recien Nacido PrematuroRESUMEN
Objective: The objective of this study is to determine whether the health effects of smoking and moderate alcohol use persist with aging. Method: Smoking status, alcohol use, and measures of function and health were obtained from 9,704 women aged ≥65 years at baseline and over 10- and 20-year follow-up periods. Adjusted multiple linear and logistic regression and Cox proportional hazard models estimated associations. Results: Current versus never smokers had worse walking speed, self-reported health, difficulty with instrumental activities of daily living (IADLs), and depression at 10 years and higher death rates at 10 and 20 years. Moderate versus never drinkers had better grip strength, walking speed, self-reported health, and less difficulty with IADLs and were less likely to live in nursing homes at 10 years and die at 10 and 20 years. Discussion: Among aging women over 20 years, smoking is associated with worse physical function, including death, while moderate alcohol use is associated with better outcomes.
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RATIONALE: Aspiration of infective subglottic secretions causes ventilator-associated pneumonia (VAP) in mechanically ventilated patients. Mechanisms underlying subglottic colonization in critical illness have not been defined, limiting strategies for targeted prevention of VAP. OBJECTIVES: To characterize subglottic host defense dysfunction in mechanically ventilated patients in the ICU; to determine whether subglottic mucin contributes to neutrophil phagocytic impairment and bacterial growth. METHODS: Prospective subglottic sampling in mechanically ventilated patients (intubated for four or more days), and newly intubated control patients (intubated for less than 30 min); isolation and culture of primary subglottic epithelial cells from control patients; laboratory analysis of host innate immune defenses. MEASUREMENTS AND MAIN RESULTS: Twenty-four patients in the ICU and 27 newly intubated control patients were studied. Subglottic ICU samples had significantly reduced microbiological diversity and contained potential respiratory pathogens. The subglottic microenvironment in the ICU was characterized by neutrophilic inflammation, significantly increased proinflammatory cytokines and neutrophil proteases, and altered physical properties of subglottic secretions, including accumulation of mucins. Subglottic mucin from ICU patients impaired the capacity of neutrophils to phagocytose and kill bacteria. Phagocytic impairment was reversible on treatment with a mucolytic agent. Subglottic mucus promoted growth and invasion of bacterial pathogens in a novel air-liquid interface model of primary human subglottic epithelium. CONCLUSIONS: Mechanical ventilation in the ICU is characterized by substantial mucin secretion and neutrophilic inflammation. Mucin impairs neutrophil function and promotes bacterial growth. Mucolytic agents reverse mucin-mediated neutrophil dysfunction. Enhanced mucus disruption and removal has potential to augment preventive benefits of subglottic drainage.
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Inflamación/inmunología , Inflamación/fisiopatología , Mucinas/inmunología , Neutrófilos/inmunología , Respiración Artificial/efectos adversos , Adulto , Anciano , Enfermedad Crítica , Femenino , Glotis/inmunología , Glotis/fisiopatología , Humanos , Inmunidad Innata/inmunología , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Adulto JovenRESUMEN
BACKGROUND: Late onset sepsis (LOS) in preterm infants is associated with considerable morbidity and mortality. While studies have implicated gut bacteria in the aetiology of the disease, functional analysis and mechanistic insights are generally lacking. We performed temporal bacterial (n = 613) and metabolomic (n = 63) profiling on extensively sampled stool from 7 infants with LOS and 28 matched healthy (no LOS or NEC) controls. RESULTS: The bacteria isolated in diagnostic blood culture usually corresponded to the dominant bacterial genera in the gut microbiome. Longitudinal changes were monitored based on preterm gut community types (PGCTs), where control infants had an increased number of PGCTs compared to LOS infants (P = 0.011). PGCT 6, characterised by Bifidobacteria dominance, was only present in control infants. Metabolite profiles differed between LOS and control infants at diagnosis and 7 days later, but not 7 days prior to diagnosis. Bifidobacteria was positively correlated with control metabolites, including raffinose, sucrose, and acetic acid. CONCLUSIONS: Using multi-omic analysis, we show that the gut microbiome is involved in the pathogenesis of LOS. While the causative agent of LOS varies, it is usually abundant in the gut. Bifidobacteria dominance was associated with control infants, and the presence of this organism may directly protect, or act as a marker for protection, against gut epithelial translocation. While the metabolomic data is preliminary, the findings support that gut development and protection in preterm infants is associated with increased in prebiotic oligosaccharides (e.g. raffinose) and the growth of beneficial bacteria (e.g. Bifidobacterium).
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Microbioma Gastrointestinal , Tracto Gastrointestinal/fisiología , Enfermedades del Prematuro/microbiología , Metaboloma , Sepsis Neonatal/microbiología , Ácido Acético/metabolismo , Traslocación Bacteriana , Bifidobacterium/aislamiento & purificación , Bifidobacterium/fisiología , Heces/microbiología , Tracto Gastrointestinal/microbiología , Humanos , Lactante , Recién Nacido , Recien Nacido Prematuro , Enfermedades del Prematuro/diagnóstico , Metabolómica/métodos , Sepsis Neonatal/diagnóstico , Rafinosa/metabolismo , Sacarosa/metabolismoRESUMEN
The short and long-term impact of birth mode on the developing gut microbiome in neonates has potential implications for the health of infants. In term infants, the microbiome immediately following birth across multiple body sites corresponds to birth mode, with increased Bacteroides in vaginally delivered infants. We aimed to determine the impact of birth mode of the preterm gut microbiome over the first 100 days of life and following neonatal intensive care unit (NICU) discharge. In total, 867 stool samples from 46 preterm infants (21 cesarean and 25 vaginal), median gestational age 27 weeks, were sequenced (V4 region 16S rRNA gene, Illumina MiSeq). Of these, 776 samples passed quality filtering and were included in the analysis. The overall longitudinal alpha-diversity and within infant beta-diversity was comparable between cesarean and vaginally delivered infants. Vaginally delivered infants kept significantly more OTUs from 2 months of life and following NICU discharge, but OTUs lost, gained, and regained were not different based on birth mode. Furthermore, the temporal progression of dominant genera was comparable between birth modes and no significant difference was found for any genera following adjustment for covariates. Lastly, preterm gut community types (PGCTs) showed some moderate differences in very early life, but progressed toward a comparable pattern by week 5. No PGCT was significantly associated with cesarean or vaginal birth. Unlike term infants, birth mode was not significantly associated with changes in microbial diversity, composition, specific taxa, or overall microbial development in preterm infants. This may result from the dominating effects of NICU exposures including the universal use of antibiotics immediately following birth and/or the lack of Bacteroides colonizing preterm infants.
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Necrotising enterocolitis (NEC) and sepsis are serious diseases of preterm infants that can result in feeding intolerance, the need for bowel resection, impaired physiological and neurological development, and high mortality rates. Neonatal healthcare improvements have allowed greater survival rates in preterm infants leading to increased numbers at risk of developing NEC and sepsis. Gut bacteria play a role in protection from or propensity to these conditions and have therefore, been studied extensively using targeted 16S rRNA gene sequencing methods. However, exact epidemiology of these conditions remain unknown and the role of the gut microbiota in NEC remains enigmatic. Many studies have confounding variables such as differing clinical intervention strategies or major methodological issues such as the inability of 16S rRNA gene sequencing methods to determine viable from non-viable taxa. Identification of viable community members is important to identify links between the microbiota and disease in the highly unstable preterm infant gut. This is especially important as remnant DNA is robust and persists in the sampling environment following cell death. Chelation of such DNA prevents downstream amplification and inclusion in microbiota characterisation. This study validates use of propidium monoazide (PMA), a DNA chelating agent that is excluded by an undamaged bacterial membrane, to reduce bias associated with 16S rRNA gene analysis of clinical stool samples. We aim to improve identification of the viable microbiota in order to increase the accuracy of clinical inferences made regarding the impact of the preterm gut microbiota on health and disease. Gut microbiota analysis was completed on stools from matched twins (n = 16) that received probiotics. Samples were treated with PMA, prior to bacterial DNA extraction. Meta-analysis highlighted a significant reduction in bacterial diversity in 68.8% of PMA treated samples as well as significantly reduced overall rare taxa abundance. Importantly, overall abundances of genera associated with protection from and propensity to NEC and sepsis such as: Bifidobacterium; Clostridium, and Staphylococcus sp. were significantly different following PMA-treatment. These results suggest non-viable cell exclusion by PMA-treatment reduces bias in gut microbiota analysis from which clinical inferences regarding patient susceptibility to NEC and sepsis are made.
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Bacterias/clasificación , Enterocolitis Necrotizante/microbiología , Microbioma Gastrointestinal , Tracto Gastrointestinal/microbiología , Azidas , Bacterias/genética , Bacterias/aislamiento & purificación , Sesgo , Biodiversidad , ADN Bacteriano/genética , Enterocolitis Necrotizante/epidemiología , Enterocolitis Necrotizante/mortalidad , Heces/microbiología , Humanos , Lactante , Recien Nacido Prematuro , Reacción en Cadena de la Polimerasa , Probióticos/uso terapéutico , Propidio/análogos & derivados , ARN Ribosómico 16S/genética , Tasa de SupervivenciaRESUMEN
Large randomized controlled trials (RCTs) in preterm infants offer unique opportunities for mechanistic evaluation of the risk factors leading to serious diseases, as well as the actions of interventions designed to prevent them. Necrotizing enterocolitis (NEC) a serious inflammatory gut condition and late-onset sepsis (LOS) are common feeding and nutrition-related problems that may cause death or serious long-term morbidity and are key outcomes in two current UK National Institutes for Health Research (NIHR) trials. Speed of increasing milk feeds trial (SIFT) randomized preterm infants to different rates of increases in milk feeds with a primary outcome of survival without disability at 2 years corrected age. Enteral lactoferrin in neonates (ELFIN) randomizes infants to supplemental enteral lactoferrin or placebo with a primary outcome of LOS. This is a protocol for the mechanisms affecting the gut of preterm infants in enteral feeding trials (MAGPIE) study and is funded by the UK NIHR Efficacy and Mechanistic Evaluation programme. MAGPIE will recruit ~480 preterm infants who were enrolled in SIFT or ELFIN. Participation in MAGPIE does not change the main trial protocols and uses non-invasive sampling of stool and urine, along with any residual resected gut tissue if infants required surgery. Trial interventions may involve effects on gut microbes, metabolites (e.g., short-chain fatty acids), and aspects of host immune function. Current hypotheses suggest that NEC and/or LOS are due to a dysregulated immune system in the context of gut dysbiosis, but mechanisms have not been systematically studied within large RCTs. Microbiomic analysis will use next-generation sequencing, and metabolites will be assessed by mass spectrometry to detect volatile organic and other compounds produced by microbes or the host. We will explore differences between disease cases and controls, as well as exploring the actions of trial interventions. Impacts of this research are multiple: translation of knowledge of mechanisms promoting gut health may explain outcomes or suggest alternate strategies to improve health. Results may identify new non-invasive diagnostic or monitoring techniques, preventative or treatment strategies for NEC or LOS, or provide data useful for risk stratification in future studies. Mechanistic evaluation might be especially informative where there are not clear effects on the primary outcome (ISRCTN 12554594).
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BACKGROUND: The preterm microbiome is crucial to gut health and may contribute to necrotising enterocolitis (NEC), which represents the most significant pathology affecting preterm infants. From a cohort of 318 infants, <32 weeks gestation, we selected 7 infants who developed NEC (defined rigorously) and 28 matched controls. We performed detailed temporal bacterial (n = 641) and metabolomic (n = 75) profiling of the gut microbiome throughout the disease. RESULTS: A core community of Klebsiella, Escherichia, Staphyloccocus, and Enterococcus was present in all samples. Gut microbiota profiles grouped into six distinct clusters, termed preterm gut community types (PGCTs). Each PGCT reflected dominance by the core operational taxonomic units (OTUs), except of PGCT 6, which had high diversity and was dominant in bifidobacteria. While PGCTs 1-5 were present in infants prior to NEC diagnosis, PGCT 6 was comprised exclusively of healthy samples. NEC infants had significantly more PGCT transitions prior to diagnosis. Metabolomic profiling identified significant pathways associated with NEC onset, with metabolites involved in linoleate metabolism significantly associated with NEC diagnosis. Notably, metabolites associated with NEC were the lowest in PGCT 6. CONCLUSIONS: This is the first study to integrate sequence and metabolomic stool analysis in preterm neonates, demonstrating that NEC does not have a uniform microbial signature. However, a diverse gut microbiome with a high abundance of bifidobacteria may protect preterm infants from disease. These results may inform biomarker development and improve understanding of gut-mediated mechanisms of NEC.
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Bacterias/clasificación , Enterocolitis Necrotizante/microbiología , Microbioma Gastrointestinal , Enfermedades del Prematuro/microbiología , Proteómica/métodos , Análisis de Secuencia de ADN/métodos , Bacterias/genética , Bacterias/aislamiento & purificación , Bacterias/metabolismo , ADN Bacteriano/análisis , ADN Ribosómico/análisis , Enterocolitis Necrotizante/metabolismo , Heces/microbiología , Femenino , Humanos , Recién Nacido , Recien Nacido Prematuro , Enfermedades del Prematuro/metabolismo , Ácido Linoleico/metabolismo , Estudios Longitudinales , Masculino , Redes y Vías Metabólicas , Filogenia , ARN Ribosómico 16S/análisisRESUMEN
OBJECTIVES: The objective of this study was to describe a novel cadaver model and to determine the utility of this model for teaching and assessing students in performing knee, elbow, and wrist arthrocentesis. METHODS: Third year medical students were evaluated while performing arthrocentesis during a fresh cadaver training sessions. RESULTS: Sixty-three participants were included in this analysis. There was statistically significant improvement between the pre- and post-test analysis in all aspects assessed in our study of elbow, knee and wrist arthrocentesis. CONCLUSIONS: The use of fresh cadavers for the education and assessment of arthrocenteses is an effective training model.
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Isolation of nontuberculous mycobacteria (NTM) from the sputum of patients with cystic fibrosis (CF) is challenging due to overgrowth by rapidly growing species that colonize the lungs of patients with CF. Extended incubation on Burkholderia cepacia selective agar (BCSA) has been recommended as an expedient culture method for the isolation of rapidly growing NTM in this setting. The aim of this study was to assess five selective media designed for the isolation of Burkholderia cepacia complex, along with two media designed for the isolation of mycobacteria (rapidly growing mycobacteria [RGM] medium and Middlebrook 7H11 agar), for their abilities to isolate NTM. All seven media were challenged with 147 isolates of rapidly growing mycobacteria and 185 isolates belonging to other species. RGM medium was then compared with the most selective brand of BCSA for the isolation of NTM from 224 sputum samples from patients with CF. Different agars designed for the isolation of B. cepacia complex varied considerably in their inhibition of other bacteria and fungi. RGM medium supported the growth of all isolates of mycobacteria and was more selective than any other medium. NTM were recovered from 17 of 224 sputum samples using RGM medium, compared with only 7 samples using the most selective brand of BCSA (P = 0.023). RGM medium offers a superior option, compared to other selective agars, for the isolation of rapidly growing mycobacteria from the sputum of patients with CF. Furthermore, the convenience of using RGM medium enables routine screening for rapidly growing NTM in all submitted sputum samples from patients with CF.
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Técnicas Bacteriológicas/métodos , Medios de Cultivo/química , Fibrosis Quística/complicaciones , Infecciones por Mycobacterium no Tuberculosas/diagnóstico , Micobacterias no Tuberculosas/aislamiento & purificación , Esputo/microbiología , Adulto , Niño , Preescolar , Femenino , Humanos , Masculino , Tamizaje Masivo/métodosAsunto(s)
Microbioma Gastrointestinal/inmunología , Trasplante de Células Madre Hematopoyéticas , Inmunodeficiencia Combinada Grave/microbiología , Inmunodeficiencia Combinada Grave/terapia , Microbioma Gastrointestinal/genética , Enfermedad Injerto contra Huésped/etiología , Enfermedad Injerto contra Huésped/microbiología , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Humanos , Lactante , Masculino , Metaboloma/inmunología , Inmunodeficiencia Combinada Grave/inmunología , Factores de TiempoRESUMEN
BACKGROUND: Probiotics are live microbial supplements that colonize the gut and potentially exert health benefit to the host. OBJECTIVES: We aimed to determine the impact of a probiotic (Infloran®: Lactobacillus acidophilus-NCIMB701748 and Bifidobacterium bifidum-ATCC15696) on the bacterial and metabolic function of the preterm gut while in the neonatal intensive care unit (NICU) and following discharge. METHODS: Stool samples (n = 88) were collected before, during, and after probiotic intake from 7 patients, along with time-matched controls from 3 patients. Samples were also collected following discharge home from the NICU. Samples underwent bacterial profiling analysis by 16S rRNA gene sequencing and quantitative PCR (qPCR), as well as metabolomic profiling using liquid chromatography mass spectrometry. RESULTS: Bacterial profiling showed greater Bifidobacterium (15.1%) and Lactobacillus (4.2%) during supplementation compared to the control group (4.0% and 0%, respectively). While Lactobacillus became reduced after the probiotic had been stopped, Bifidobacterium remained high following discharge, suggestive of successful colonisation. qPCR analysis showed a significant increase (p ≤ 0.01) in B. bifidum in infants who received probiotic treatment compared to controls, but no significant increase was observed for L. acidophilus (p = 0.153). Metabolite profiling showed clustering based on receiving probiotic or matched controls, with distinct metabolites associated with probiotic administration. CONCLUSIONS: Probiotic species successfully colonise the preterm gut, reducing the relative abundance of potentially pathogenic bacteria, and effecting gut functioning. Bifidobacterium (but not Lactobacillus) colonised the gut in the long term, suggesting the possibility that therapeutically administered probiotics may continue to exert important functional effects on gut microbial communities in early infancy.