Clostridioides difficile is the leading cause of nosocomial intestinal infections in the United States. Ingested C. difficile spores encounter host bile acids and other cues that are necessary for ...germinating into toxin-producing vegetative cells. While gut microbiota disruption (often by antibiotics) is a prerequisite for C. difficile infection (CDI), the mechanisms C. difficile employs for colonization remain unclear. Here, we pioneered the application of imaging mass spectrometry to study how enteric infection changes gut metabolites. We find that CDI induces an influx of bile acids into the gut within 24 h of the host ingesting spores. In response, the host reduces bile acid biosynthesis gene expression. These bile acids drive C. difficile outgrowth, as mice receiving the bile acid sequestrant cholestyramine display delayed colonization and reduced germination. Our findings indicate that C. difficile may facilitate germination upon infection and suggest that altering flux through bile acid pathways can modulate C. difficile outgrowth in CDI-prone patients.
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•Imaging mass spectrometry (IMS) is applied to study C. difficile infection (CDI)•IMS reveals a rapid influx of bile acids into the gut during CDI•The host then reduces transcriptional flux through bile acid biosynthesis pathways•Increased bile acids contribute to C. difficile spore germination and outgrowth
To illuminate how the gut environment changes during enteric infection, Wexler, Guiberson et al. measured the abundances and distributions of gut metabolites during C. difficile infection using imaging mass spectrometry. They find that C. difficile rapidly alters host bile acid physiology during colonization, which facilitates spore germination and outgrowth.
Abstract
Objectives
To control the emerging threat of antimicrobial resistance, international policy appeals for appropriate monitoring of antimicrobial usage (AMU) at supranational, species and farm ...level. The aim of this study was to quantify AMU in broilers at farm and flock level in nine European countries.
Methods
Antimicrobial treatment data of one flock and purchased antimicrobials over one year were collected at 181 European broiler farms. Afterwards AMU was quantified using treatment incidence (TI) per 100 days based on Defined Daily Dose (DDDvet), Defined Course Dose (DCDvet) or Used Daily Dose (UDDvet) values. Total AMU at flock level was obtained by summing the TIDDDvet of all treatments in the sampled flock (TIDDDvetFl*).
Results
The median TIDDDvetFl* was 9.0 (95% CI 5.5–10.8), meaning that broilers were treated with antimicrobials during 9% of their rearing period. TIDDDvetFl* varied considerably within and between countries. However, in every country at least one untreated flock was present. Average TIDDDvetFl* at country level ranged from 3.3 to 36.7. Polymyxins, extended-spectrum aminopenicillins and fluoroquinolones were the most used antimicrobials, accounting for 26%, 26% and 18% of total AMU, respectively. Twenty-six percent of the farms started a treatment on day 1 of production, and 49% of overall AMU was administered within the first week.
Conclusions
Results show that rearing broilers without AMU is feasible. However, a huge variation in AMU in terms of amount, moment of administration and antimicrobial classes was observed. This shows that there is still ground to be covered when it comes to AMU on broiler farms.
Parasites are major effectors of natural selection and also play a role in sexual selection processes. Haemosporidian blood parasites are common in vertebrates and have been shown to vary in their ...effects depending on both the parasite and host species, on the host trait investigated as well as on host condition and stage of infection. Here we investigated infection of adult barn swallows Hirundo rustica by Plasmodium, Leucocytozoon and Haemoproteus species during the chronic stage of infection and the consequences for host fitness traits. Prevalence was higher than 10% only for Plasmodium. Chronic stage infection by Plasmodium was associated with reduced female breeding success, but did not affect breeding dates. Infection did not affect the expression of male secondary sexual traits (tail length and melanin‐based plumage coloration), but was associated with paler coloration of females. Finally, we found a negative effect of infection by Plasmodium on feather growth rate in older but not in yearling individuals. Because feathers are moulted during wintering in sub‐Saharan Africa where infection of barn swallows by Plasmodium occurs, our results suggest that male secondary sexual traits have little potential to reveal acute‐stage infection whereas plumage coloration of females may advertise their infection status. In addition, these results suggest that infection by Plasmodium can influence the course of plumage moult. Thus, our results add to the observations of negative effects of haemosporidian infection on fitness traits in birds and provides evidence that these effects can vary among traits and in relation to age and sex.
Abstract
Observations from past missions such as RXTE and Beppo-SAX suggested the presence of inverse Compton (IC) scattering at hard X-ray energies within the intracluster medium of some massive ...galaxy clusters. In subsequent years, observations by, e.g., Suzaku, and now NuSTAR, have not been able to confirm these detections. We report on NuSTAR hard X-ray searches for IC emission in two massive galaxy clusters, A665 and A2146. To constrain the global IC flux in these two clusters, we fit global NuSTAR spectra with three models: single (1T) and two-temperature (2T) models, and a 1T plus power-law component (T+IC). The temperature components are meant to characterize the thermal ICM emission, while the power law represents the IC emission. We find that the 3–30 keV A665 and 3–20 keV A2146 spectra are best described by thermal emission alone, with average global temperatures of
kT
= (9.15 ± 0.1) keV for A665 and
kT
= (8.29 ± 0.1) keV for A 2146. We constrain the IC flux to
F
NT
<0.60 × 10
−12
erg s
−1
cm
−2
and
F
NT
< 0.85 × 10
−12
erg s
−1
cm
−2
(20–80 keV) for A665 and A2146, respectively both at the 90% confidence level. When we couple the IC flux limits with 1.4 GHz diffuse radio data from the VLA, we set lower limits on the average magnetic field strengths of >0.14
μ
G and >0.011
μ
G for A665 and A2146, respectively.
Abstract
Background and Aims:
Efforts to slow or prevent the progressive course of inflammatory bowel diseases IBD include early and intensive monitoring and treatment of patients at higher risk for ...complications. It is therefore essential to identify high-risk patients – both at diagnosis and throughout disease course.
Methods:
As a part of an IBD Ahead initiative, we conducted a comprehensive literature review to identify predictors of long-term IBD prognosis and generate draft expert summary statements. Statements were refined at national meetings of IBD experts in 32 countries and were finalized at an international meeting in November 2014.
Results:
Patients with Crohn’s disease presenting at a young age or with extensive anatomical involvement, deep ulcerations, ileal/ileocolonic involvement, perianal and/or severe rectal disease or penetrating/stenosing behaviour should be regarded as high risk for complications. Patients with ulcerative colitis presenting at young age, with extensive colitis and frequent flare-ups needing steroids or hospitalization present increased risk for colectomy or future hospitalization. Smoking status, concurrent primary sclerosing cholangitis and concurrent infections may impact the course of disease. Current genetic and serological markers lack accuracy for clinical use.
Conclusions:
Simple demographic and clinical features can guide the clinician in identifying patients at higher risk for disease complications at diagnosis and throughout disease course. However, many of these risk factors have been identified retrospectively and lack validation. Appropriately powered prospective studies are required to inform algorithms that can truly predict the risk for disease progression in the individual patient.
Inflammatory bowel diseases (IBD) affect the gastrointestinal tract: they include Crohn's disease (CD) and ulcerative colitis (UC). Each has a different phenotypic spectrum, characterized by ...gastrointestinal and extra-intestinal manifestations. People living with IBD are very interested in diet, but little is known about the impact of diet on these patients; no guidelines are available yet. In this review, we analyze the dietary patterns of patients with IBD and the approach to the choices of foods both in adults and pediatric patients. Very often, IBD patients report an intentional avoidance of gluten to manage the disease; furthermore, a proportion of IBD patients believe that dairy products worsen their symptoms and that avoidance may help the disease. They have a low compliance with the Mediterranean Diet, which is considered to have potential benefits but is little used in practice. In conclusion, the review underscores the pivotal role of nutritional counselling in IBD patients, and the importance of future clinical studies to evaluate the beneficial effects of dietary recommendations in the management of IBD.
The aim of the study was to identify new potential chemical markers of extra virgin olive oil (EVOO) quality by using a multicomponent analysis approach. Sixty-six EVOOs were purchased from the ...Italian market and classified according to their price as low price EVOOs (LEVOOs) and high price EVOOs (HEVOOs) costing 3.60–5.90euro/L and 7.49–29.80euro/L respectively. Sensory and chemical parameters strictly related to olive oil quality have been investigated, like volatile substances, polar phenolic substances, antioxidant activity, fatty acid composition, and α-tocopherol. Significant differences in terms of chemical composition and sensory features have been highlighted between the two EVOOs classes investigated, proving a generally lower level of quality of LEVOOs, clearly showed also by means of principal component analysis. Among the most interesting outcomes, R ratio (free tyrosol and hydroxytyrosol over total free and bound forms), measuring the extent of secoiridoids hydrolysis, resulted to be significantly higher in LEVOOs than in HEVOOs. Other key differences were found in the volatile substances composition, in the stearic acid percentage and in p-coumaric acid content.
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•Multicomponent study on low (LEVOO) and high price extra virgin olive oils (HEVOO)•Significantly higher sensory quality in HEVOOs than in LEVOOs•R ratio (indicating hydrolysis extent of secoiridoids) significantly higher in LEVOO than in HEVOO•Ratio hexanal/2-(E)-hexenal significantly higher in LEVOO than in HEVOO•Stearic acid % and p-coumaric acid content significantly higher in LEVOO than in HEVOO
The moon jellyfish Aurelia coerulea (Scyphozoa) is one of the most common and largest jellyfish inhabiting coastal lagoons, confined bays, and marinas of temperate and subtropical coastal waters. The ...annual population dynamics of A. coerulea along with some bacterial parameters (bacterial size and biomass, total coliforms, faecal coliforms, intestinal enterococci, culturable Vibrio spp., and culturable bacteria at 37 °C), sea surface temperature (SST), salinity, and an array of nutrients (ammonia, nitrites, nitrates, phosphates, silicates, total nitrogen, and total phosphorus) were assessed in the Varano lagoon (Adriatic Sea) that is subject to anthropogenic pollution. Statistical analyses revealed that jellyfish outbreaks and their consequent biomass deposition significantly correlated to seawater temperature, total nitrogen, phosphates, and ammonia concentrations while negative correlations appeared with nitrite and nitrate concentrations. In addition, bacterial biomass and Vibrio abundance correlated with each other and temperature, jellyfish density, and total nitrogen. These findings suggest that environmental changes could trigger the occurrence of jellyfish bursts in the lagoon which, in turn, may act as one of the central drivers of processes regulating some bacterial components. The positive relationship between jellyfish flush-and-crash dynamics and SST suggests that ongoing global warming will seemingly increase jellyfish outbreaks.
A retrospective telephone survey (n=3490) was conducted in Italy between 2008 and 2009 to estimate the occurrence of self-reported acute gastrointestinal illness (AGI) and to describe subjects' ...recourse to healthcare, using a symptom-based case definition. Three hundred and ten AGI cases were identified. The annual incidence rate was 1·08 episodes/person-year (95% confidence interval 0·90–1·14). The proportion of subjects consulting physicians was 39·5% while only 0·3% submitted a specimen for laboratory investigation. Risk factors for AGI and medical care-seeking were identified using logistic regression analysis. Females, children and young adults had a significantly higher incidence rate of AGI. Factors associated with medical care-seeking were age <10 years, presence of fever, diarrhoea, and duration of illness >3 days. Our results provide a relevant contribution towards estimating the global burden of AGI using standard methods that ensure a good level of comparability with other studies.
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