85 research outputs found
Pyrosequencing Unveils Cystic Fibrosis Lung Microbiome Differences Associated with a Severe Lung Function Decline
Chronic airway infection is a hallmark feature of cystic fibrosis (CF) disease. In the present study, sputum samples from CF patients were collected and characterized by 16S rRNA gene-targeted approach, to assess how lung microbiota composition changes following a severe decline in lung function. In particular, we compared the airway microbiota of two groups of patients with CF, i.e. patients with a substantial decline in their lung function (SD) and patients with a stable lung function (S). The two groups showed a different bacterial composition, with SD patients reporting a more heterogeneous community than the S ones. Pseudomonas was the dominant genus in both S and SD patients followed by Staphylococcus and Prevotella. Other than the classical CF pathogens and the most commonly identified non-classical genera in CF, we found the presence of the unusual anaerobic genus Sneathia. Moreover, the oligotyping analysis revealed the presence of other minor genera described in CF, highlighting the polymicrobial nature of CF infection. Finally, the analysis of correlation and anti-correlation networks showed the presence of antagonism and ecological independence between members of Pseudomonas genus and the rest of CF airways microbiota, with S patients showing a more interconnected community in S patients than in SD ones. This population structure suggests a higher resilience of S microbiota with respect to SD, which in turn may hinder the potential adverse impact of aggressive pathogens (e.g. Pseudomonas). In conclusion, our findings shed a new light on CF airway microbiota ecology, improving current knowledge about its composition and polymicrobial interactions in patients with CF
Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis
BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London
Surgical site infection after gastrointestinal surgery in high-income, middle-income, and low-income countries: a prospective, international, multicentre cohort study
Background: Surgical site infection (SSI) is one of the most common infections associated with health care, but its importance as a global health priority is not fully understood. We quantified the burden of SSI after gastrointestinal surgery in countries in all parts of the world.
Methods: This international, prospective, multicentre cohort study included consecutive patients undergoing elective or emergency gastrointestinal resection within 2-week time periods at any health-care facility in any country. Countries with participating centres were stratified into high-income, middle-income, and low-income groups according to the UN's Human Development Index (HDI). Data variables from the GlobalSurg 1 study and other studies that have been found to affect the likelihood of SSI were entered into risk adjustment models. The primary outcome measure was the 30-day SSI incidence (defined by US Centers for Disease Control and Prevention criteria for superficial and deep incisional SSI). Relationships with explanatory variables were examined using Bayesian multilevel logistic regression models. This trial is registered with ClinicalTrials.gov, number NCT02662231.
Findings: Between Jan 4, 2016, and July 31, 2016, 13 265 records were submitted for analysis. 12 539 patients from 343 hospitals in 66 countries were included. 7339 (58·5%) patient were from high-HDI countries (193 hospitals in 30 countries), 3918 (31·2%) patients were from middle-HDI countries (82 hospitals in 18 countries), and 1282 (10·2%) patients were from low-HDI countries (68 hospitals in 18 countries). In total, 1538 (12·3%) patients had SSI within 30 days of surgery. The incidence of SSI varied between countries with high (691 [9·4%] of 7339 patients), middle (549 [14·0%] of 3918 patients), and low (298 [23·2%] of 1282) HDI (p < 0·001). The highest SSI incidence in each HDI group was after dirty surgery (102 [17·8%] of 574 patients in high-HDI countries; 74 [31·4%] of 236 patients in middle-HDI countries; 72 [39·8%] of 181 patients in low-HDI countries). Following risk factor adjustment, patients in low-HDI countries were at greatest risk of SSI (adjusted odds ratio 1·60, 95% credible interval 1·05–2·37; p=0·030). 132 (21·6%) of 610 patients with an SSI and a microbiology culture result had an infection that was resistant to the prophylactic antibiotic used. Resistant infections were detected in 49 (16·6%) of 295 patients in high-HDI countries, in 37 (19·8%) of 187 patients in middle-HDI countries, and in 46 (35·9%) of 128 patients in low-HDI countries (p < 0·001).
Interpretation: Countries with a low HDI carry a disproportionately greater burden of SSI than countries with a middle or high HDI and might have higher rates of antibiotic resistance. In view of WHO recommendations on SSI prevention that highlight the absence of high-quality interventional research, urgent, pragmatic, randomised trials based in LMICs are needed to assess measures aiming to reduce this preventable complication
Closed innovation vs Open innovation: cambiamenti nei modelli di business. Il caso LEGO
Alla luce dell’avvento della digitalizzazione, il tema dell’innovazione assume un nuovo significato.
Il primo capitolo analizza i limiti del modello dell’innovazione chiusa, quindi le dinamiche che hanno condotto alla diffusione dell’open innovation.
Nel secondo capitolo vengono presentati i tre pilastri dell’innovazione e una descrizione della giusta configurazione business model, affinché risultino adeguate al nuovo contesto competitivo.
Nel terzo capitolo viene introdotto il caso LEGO Group. Un nuovo approccio (open) all’innovazione e una ridefinizione delle variabili del business model ha consentito a LEGO di superare la crisi e rinascere più forte di prima
Erosional characteristics and behavior of large pyroclastic density currents
Factors influencing the erosive behavior of large pyroclastic density currents (PDCs), both mainly massive and thinly stratified, are not well understood. To investigate the parameters influencing the erosive behavior of PDCs produced during the flowing phase of large, caldera-forming Plinian (Campanian Ignimbrite) and phreatoplinian (Neapolitan Yellow Tuff) eruptions, we use scoured fall deposits at the base of, or interstratified with, PDC deposits from the Campanian region of Italy. At several localities, we calculated the depth of PDC erosion by comparing the measured thickness of eroded remnants to reconstructed thickness at each site (estimated by isopach mapping), and recorded the (1) distance from vent, (2) elevation of the locality, and (3) paleoslopes. Furthermore, we have considered how these factors can be influenced by outcrop exposure. Depth of erosion correlates with distance from the vent in low-relief landscape, while across very rugged topography the only related parameter is elevation. The different erosive patterns appear to show how pyroclastic currents interact with the topography in the surrounding terrain. When a PDC crosses relatively flat surfaces, it decelerates away from the vent, decreasing its erosive capacity; but when moving through steep terrain, a PDC accelerates down the valley, increasing its erosive capacity
Stratigraphy and physical parameters of the Plinian phase of the Campanian Ignimbrite eruption
The Campanian Ignimbrite eruption
(39 ka) was the most powerful eruptive event
of the Campi Flegrei caldera (southern Italy).
This event coincided with the onset of a cold
climatic phase and the Paleolithic transition
from Neanderthals to modern humans. The
eruption started with a sustained column
that emplaced a widespread pyroclastic fall
deposit covering an area >4000 km2 within
the 15 cm isopach. For the first time, we present
the complete longitudinal variation from
the coarse and 10-m-thick proximal (down
to 15 km) sequence, through the well-stratified
pumice lapilli deposit in medial areas
(30–80 km), to the distal tephra (hundreds to
thousands of kilometers distant). The Plinian
pumice fall deposit shows a strong lateral
heterogeneity due to variations in stratification,
grading, and abundance of components.
All Campanian Ignimbrite fall layers display
Plinian dispersal. Variation of grain size with
stratigraphic height suggests that the convective
plume was far from steady state. Initially,
the plume dispersed 1.3 km3 of tephra toward
the ENE (N75°E) from a height of 29 km
(layer A). A gradual increase in intensity resulted
in inverse grading of layer B. Column
height increased from 26 to 37 km at a vertical
velocity of 3.6 m/s. It had a main dispersal
axis to the east (N97°E) and a secondary lobe
to the southeast (N137°E). During this phase,
a maximum volume of 1.73 km3 of tephra was
emplaced. Accessory lithics concentrated in
layer C are possibly due to vent clearing after
partial blockage of the vent. The 33-km-high
column dispersed ejecta to the east (N95°E),
with only 0.2 km3 of tephra erupted during
this phase. During the successive gradual
decline in eruption intensity (column height
decreased from 38 to 32 km at a velocity of
4.2 m/s), a normally graded layer (D) with
a volume of 1 km3 accumulated to the east
(N95°E). The sustained column phase ended
with a pulsating and partially collapsing column
that reached 23 km in height and dispersed
1.1 km3 of a stratified and lithic-rich
succession (layer E) to the southeast (N112°E).
If we include the distal co-Plinian deposit, a
total volume of 7.8 km3 (dense rock equivalent
[DRE]) of magma was released (containing
0.09 km3 of accessory lithics). Tephra mass
for the single layers is on the order of 1011 kg,
and the total mass is ~2 × 1012 kg (2 × 1013 kg
including the co-Plinian ash). Mass discharge
rates ranged from 0.9 to 6.7 × 108 kg/s. The
calculated magnitude of the sustained column
phase is 6.3. The duration of the Plinian
phase of this eruption, based on the ratio of
two parameters,
erupted mass divided by discharge
rate, is estimated to have been ~20 h
(including co-Plinian ash).
This study shows that Plinian deposits are
not always homogeneous and, as for pyroclastic
current deposits, can show an articulate
architecture. Only the complete reconstruction
of vertical and lateral variations
in components, stratification, and grading
might provide insights into the temporal and
spatial evolution of the sustained plum
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