•The algorithm allows individual differential diagnosis of PD and PSP by means of MR images.•The algorithm does not require a priori hypotheses of where useful information may be coded in the ...images.•Classification accuracy was significantly higher compared to other published methods.•The algorithm was able to obtain voxel-based morphological biomarkers of PD and PSP.
Supervised machine learning has been proposed as a revolutionary approach for identifying sensitive medical image biomarkers (or combination of them) allowing for automatic diagnosis of individual subjects. The aim of this work was to assess the feasibility of a supervised machine learning algorithm for the assisted diagnosis of patients with clinically diagnosed Parkinson's disease (PD) and Progressive Supranuclear Palsy (PSP).
Morphological T1-weighted Magnetic Resonance Images (MRIs) of PD patients (28), PSP patients (28) and healthy control subjects (28) were used by a supervised machine learning algorithm based on the combination of Principal Components Analysis as feature extraction technique and on Support Vector Machines as classification algorithm. The algorithm was able to obtain voxel-based morphological biomarkers of PD and PSP.
The algorithm allowed individual diagnosis of PD versus controls, PSP versus controls and PSP versus PD with an Accuracy, Specificity and Sensitivity>90%. Voxels influencing classification between PD and PSP patients involved midbrain, pons, corpus callosum and thalamus, four critical regions known to be strongly involved in the pathophysiological mechanisms of PSP.
Classification accuracy of individual PSP patients was consistent with previous manual morphological metrics and with other supervised machine learning application to MRI data, whereas accuracy in the detection of individual PD patients was significantly higher with our classification method.
The algorithm provides excellent discrimination of PD patients from PSP patients at an individual level, thus encouraging the application of computer-based diagnosis in clinical practice.
To investigate the impact of colonization with carbapenemase-producing Enterobacteriaceae (CPE) on the CPE infection risk after liver transplantation (LT).
Prospective cohort study of all adult ...patients undergoing LT at our centre over an 8-year period (2010–2017). Individuals were screened for CPE colonization by rectal swabs at inclusion onto the waiting list, immediately before LT and weekly after LT until hospital discharge. Asymptomatic carriers did not receive decolonization, anti-CPE prophylaxis or pre-emptive antibiotic therapy. Participants were followed up for 1 year after LT.
We analysed 553 individuals who underwent a first LT, 38 were colonized with CPE at LT and 104 acquired colonization after LT. CPE colonization rates at LT and acquired after LT increased significantly over the study period: incidence rate ratios (IRR) 1.21 (95% CI 1.05–1.39) and 1.17 (95% CI 1.07–1.27), respectively. Overall, 57 patients developed CPE infection within a median of 31 (interquartile range 11–115) days after LT, with an incidence of 3.05 cases per 10 000 LT-recipient-days and a non-significant increase over the study period (IRR 1.11, 95% CI 0.98–1.26). In multivariable analysis, CPE colonization at LT (hazard ratio (HR) 18.50, 95% CI 6.76–50.54) and CPE colonization acquired after LT (HR 16.89, 95% CI 6.95–41.00) were the strongest risk factors for CPE infection, along with combined transplant (HR 2.60, 95% CI 1.20–5.59), higher Model for End-Stage Liver Disease at the time of LT (HR 1.03, 95% CI 1.00–1.07), prolonged mechanical ventilation (HR 2.63, 95% CI 1.48–4.67), re-intervention (HR 2.16, 95% CI 1.21–3.84) and rejection (HR 2.81, 95% CI 1.52–5.21).
CPE colonization at LT or acquired after LT were the strongest predictors of CPE infection. Prevention strategies focused on LT candidates and recipients colonized with CPE should be investigated.
The aim of this study was to evaluate the risk factors for candidaemia in patients with liver cirrhosis.
This was a case–control–control (1:2:2) study performed in four Italian tertiary centres from ...2006 to 2015. Cases were patients with liver cirrhosis developing candidaemia. For every case of candidaemia we enrolled two additional patients undergoing blood cultures for suspected infection yielding isolation of a bacterial pathogen (control A) and two additional patients undergoing blood cultures for suspected infection yielding negative results (control B). Patients were matched according to age, sex and model for end stage liver disease at hospital admission.
During the study period 90 cases, 180 controls A and 180 controls B were included. At multivariate analysis assessed by means of multinomial conditional regression models, factors independently associated with candidaemia were previous (<30 days) acute-on-chronic liver failure (relative risk ratio (RRR) 2.22 (95% confidence interval (CI) 1.09–4.54), p = 0.046), previous(<30 days) gastrointestinal endoscopy (RRR 2.38 (95% CI 1.19–4.78) p = 0.014), previous(<30 days) antibiotic treatment for at least 7 days (RRR 2.74 (95% CI 1.00–7.48), p = 0.049), presence of central venous catheter (RRR 2.77 (95% CI 1.26–6.09, p = 0.011), total parenteral nutrition (RRR 3.90 (95% CI 1.62–9.40), p = 0.002) at infection onset and length of in-hospital stay >15 days (RRR 4.63 (95% CI 2.11–10.18), p <0.001 Conversely, rifaximin treatment was associated with lower rate of candidaemia (RRR 0.38 (95% CI 0.19–0.77), p = 0.007). Multivariable analysis for 30-day mortality showed that patients with isolation of Candida spp. from blood cultures had worse outcome when compared with controls even though the difference did not reach a statistical significance (hazard ratio 1.64 (95% 0.97–2.75) p = 0.06).
We identified previous antibiotic use, gastrointestinal endoscopy or acute-on-chronic liver failure and presence of central venous catheter especially for parenteral nutrition as independent factors associated with candidaemia. Surprisingly, chronic rifaximin use was a protective factor.
The daily patterns of feed intake and rumination influence rumen fermentation, rumen pH, and timing of absorbed nutrients in the dairy cow, but the effects of diet composition on these patterns are ...not well characterized. Data from 3 previously published experiments were examined to determine the influence of dietary starch, fiber, and fatty acids (FA) on daily patterns of intake, rumination, and rumen pH. Dietary neutral detergent fiber (NDF) and starch were investigated in 2 experiments, each with duplicated 4 × 4 Latin square designs with a 2 × 2 factorial arrangement of treatments in cows fed cows 1×/d at 1200 and 1400 h, respectively. To investigate fiber content and digestibility in the first experiment, brown midrib or isogenic conventional corn silage were fed in low- and high-NDF diets (29 and 38%, respectively). To investigate starch source and concentration in the second experiment, ground high-moisture corn or dry ground corn were fed in low- and high-starch diets (21 and 32%, respectively). Effect of fat concentration and saturation was investigated in the third experiment using a replicated 4 × 4 Latin square design that fed cows 1×/d at 0900 h; treatments included a control diet with no added fat and 2.5% added saturated FA, unsaturated FA, or a mixture of the saturated and unsaturated FA. In the first 2 experiments, intake followed a similar daily pattern regardless of starch and NDF concentration or digestibility. Rumination displayed a treatment by time interaction for both NDF and starch concentration, with high-fiber, low-starch diets causing greater rumination overnight but not midday. High-starch diets decreased total daily rumen pH equally across the day, but did not change the daily pattern. Type of corn silage did not affect the daily patterns of rumination or rumen pH, but pH was reduced throughout the day in brown midrib diets. In the third experiment, no interactions between fatty acid supplement and time of day were observed for intake, rumination, or rumen pH. Within all experiments, rumination fit or tended to fit a 24-h rhythm regardless of diet, with the amplitude of the rumination being reduced in low-starch diets and diets containing saturated FA or a mixture of saturated and unsaturated FA. Overall, intake, rumination, and rumen pH follow a daily pattern that was minimally modified by dietary fiber and starch type and level or fat level and fatty acid profile.
The well-known Crab Nebula is at the center of the SN1054 supernova remnant. It consists of a rotationally powered pulsar interacting with a surrounding nebula through a relativistic particle wind. ...The emissions originating from the pulsar and nebula have been considered to be essentially stable. Here, we report the detection of strong gamma-ray (100 mega-electron volts to 10 giga-electron volts) flares observed by the AGILE satellite in September 2010 and October 2007. In both cases, the total gamma-ray flux increased by a factor of three compared with the non-flaring flux. The flare luminosity and short time scale favor an origin near the pulsar, and we discuss Chandra Observatory x-ray and Hubble Space Telescope optical follow-up observations of the nebula. Our observations challenge standard models of nebular emission and require power-law acceleration by shock-driven plasma wave turbulence within an approximately 1-day time scale.
Primary transplantation offers longer life‐expectancy in comparison to hepatic resection (HR) for hepatocellular carcinoma (HCC) followed by salvage transplantation; however, livers not used for ...primary transplantation can be reallocated to the remaining waiting‐list patients, thus, the harm caused to resected patients could be balanced, or outweighed, by the benefit obtained from reallocation of livers originating from HCC patients first being resected. A Markov model was developed to investigate this issue based on literature data or estimated from the United Network for Organ Sharing database. Markov model shows that primary transplantation offers longer life‐expectancy in comparison to HR and salvage transplantation if 5‐year posttransplant survival remains higher than 60%. The balance between the harm for resected patients and the benefit for the remaining waiting list depends on (a) the proportion of HCC candidates, (b) the percentage shifted to HR and (c) the median expected time‐to‐transplant. Faced with a low proportion of HCC candidates, the harm caused to resected patients was higher than the benefit that could be obtained for the waiting‐list population from re‐allocation of extra livers. An increased proportion of HCC candidates and/or an increased median time‐to‐transplant could lead to a benefit for waiting‐list patients that outweighs this harm.
A Markov model developed to investigate this issue found that the balance of benefit and harm is determined by the proportion of HCC candidates, the percentage shifted to hepatic resection, and the expected waiting time.
Improved understanding of risk factors associated with carbapenem‐resistant‐Klebsiella pneumoniae (CR‐KP) infection after liver transplantation (LT) can aid development of effective preventive ...strategies. We performed a prospective cohort study of all adult patients undergoing LT at our hospital during 30‐month period to define risk factors associated with CR‐KP infection. All patients were screened for CR‐KP carriage by rectal swabs before and after LT. No therapy was administered to decolonize or treat asymptomatic CR‐KP carriers. All patients were monitored up to 180 days after LT. Of 237 transplant patients screened, 41 were identified as CR‐KP carriers (11 at LT, 30 after LT), and 20 developed CR‐KP infection (18 bloodstream‐infection, 2 pneumonia) a median of 41.5 days after LT. CR‐KP infection rates among patients non‐colonized, colonized at LT, and colonized after LT were 2%, 18.2% and 46.7% (p < 0.001). Independent risk factors for CR‐KP infection identified by multivariate analysis, included: renal‐replacement‐therapy; mechanical ventilation > 48 h; HCV recurrence, and colonization at any time with CR‐KP. Based on these four variables, we developed a risk score that effectively discriminated patients at low versus higher risk for CR‐KP infection (AUC 0.93, 95% CI 0.86–1.00, p < 0.001). Our results may help to design preventive strategies for LT recipients in CR‐KP endemic areas.
In a single‐center prospective cohort study to assess the risk factors for infection with carbapenem‐resistant Klebsiella pneumoniae after liver transplantation, the authors analyze the significance of carbapenem‐resistant K. pneumoniae rectal carriage before and after liver transplantation, and develop a risk score that effectively discriminates patients at low versus higher risk for infection.
Many patients with asthma or chronic obstructive pulmonary disease (COPD) routinely receive a combination of an inhaled bronchodilator and anti-inflammatory glucocorticosteroid, but those with severe ...disease often respond poorly to these classes of drug. We assessed the efficacy and safety of a novel inhaled dual phosphodiesterase 3 (PDE3) and PDE4 inhibitor, RPL554 for its ability to act as a bronchodilator and anti-inflammatory drug.
Between February, 2009, and January, 2013, we undertook four proof-of-concept clinical trials in the Netherlands, Italy, and the UK. Nebulised RPL554 was examined in study 1 for safety in 18 healthy men who were randomly assigned (1:1:1) to receive an inhaled dose of RPL554 (0·003 mg/kg or 0·009 mg/kg) or placebo by a computer-generated randomisation table. Subsequently, six non-smoking men with mild allergic asthma received single doses of RPL554 (three received 0·009 mg/kg and three received 0·018 mg/kg) in an open-label, adaptive study, and then ten men with mild allergic asthma were randomly assigned to receive placebo or RPL554 (0·018 mg/kg) by a computer-generated randomisation table for an assessment of safety, bronchodilation, and bronchoprotection. Study 2 examined the reproducibility of the bronchodilator response to a daily dose of nebulised RPL554 (0·018 mg/kg) for 6 consecutive days in a single-blind (patients masked), placebo-controlled study in 12 men with clinically stable asthma. The safety and bronchodilator effect of RPL554 (0·018 mg/kg) was assessed in study 3, an open-label, placebo-controlled crossover trial, in 12 men with mild-to-moderate COPD. In study 4, a placebo-controlled crossover trial, the effect of RPL554 (0·018 mg/kg) on lipopolysaccharide-induced inflammatory cell infiltration in induced sputum was investigated in 21 healthy men. In studies 3 and 4, randomisation was done by computer-generated permutation with a block size of two for study 3 and four for study 4. Unless otherwise stated, participants and clinicians were masked to treatment assignment. Analyses were by intention to treat. All trials were registered with EudraCT, numbers 2008-005048-17, 2011-001698-22, 2010-023573-18, and 2012-000742-34.
Safety was a primary endpoint of studies 1 and 3 and a secondary endpoint of studies 2 and 4. Overall, RPL554 was well tolerated, and adverse events were generally mild and of equal frequency between placebo and active treatment groups. Efficacy was a primary endpoint of study 2 and a secondary endpoint of studies 1 and 3. Study 1 measured change in forced expiratory volume in 1 s (FEV1) and provocative concentration of methacholine causing a 20% fall in FEV1 (PC20MCh) in participants with asthma. RPL554 produced rapid bronchodilation in patients with asthma with an FEV1 increase at 1 h of 520 mL (95% CI 320-720; p<0·0001), which was a 14% increase from placebo, and increased the PC20MCh by 1·5 doubling doses (95% CI 0·63-2·28; p=0·004) compared with placebo. The primary endpoint of study 2 was maximum FEV1 reached during 6 h after dosing with RPL554 in patients with asthma. RPL554 produced a similar maximum mean increase in FEV1 from placebo on day 1 (555 mL, 95% CI 442-668), day 3 (505 mL, 392-618), and day 6 (485 mL, 371-598; overall p<0·0001). A secondary endpoint of study 3 (patients with COPD) was the increase from baseline in FEV1. RPL554 produced bronchodilation with a mean maximum FEV1 increase of 17·2% (SE 5·2). In healthy individuals (study 4), the primary endpoint was percentage change in neutrophil counts in induced sputum 6 h after lipopolysaccharide challenge. RPL554 (0·018 mg/kg) did not significantly reduce the percentage of neutrophils in sputum (80·3% in the RPL554 group vs 84·2% in the placebo group; difference -3·9%, 95% CI -9·4 to 1·6, p=0·15), since RPL554 significantly reduced neutrophils (p=0·002) and total cells (p=0·002) to a similar degree.
In four exploratory studies, inhaled RPL554 is an effective and well tolerated bronchodilator, bronchoprotector, and anti-inflammatory drug and further studies will establish the full potential of this new drug for the treatment of patients with COPD or asthma.
Verona Pharma.
Context. The intrinsic shape of galactic bulges in nearby galaxies provides crucial information to separate bulge types. Aims. We aim to derive accurate constraints to the intrinsic shape of bulges ...to provide new clues on their formation mechanisms and set new limitations for future simulations. Methods. We retrieved the intrinsic shape of a sample of CALIFA bulges using a statistical approach. Taking advantage of GalMer numerical simulations of binary mergers we estimated the reliability of the procedure. Analyzing the i-band mock images of resulting lenticular remnants, we studied the intrinsic shape of their bulges at different galaxy inclinations. Finally, we introduced a new (B/A, C/A) diagram to analyze possible correlations between the intrinsic shape and the properties of bulges. Results. We tested the method on simulated lenticular remnants, finding that for galaxies with inclinations of 25° ≤ θ ≤ 65° we can safely derive the intrinsic shape of their bulges. We found that our CALIFA bulges tend to be nearly oblate systems (66%), with a smaller fraction of prolate spheroids (19%), and triaxial ellipsoids (15%). The majority of triaxial bulges are in barred galaxies (75%). Moreover, we found that bulges with low Sérsic indices or in galaxies with low bulge-to-total luminosity ratios form a heterogeneous class of objects; additionally, bulges in late-type galaxies or in less massive galaxies have no preference for being oblate, prolate, or triaxial. On the contrary, bulges with high Sérsic index, in early-type galaxies, or in more massive galaxies are mostly oblate systems. Conclusions. We concluded that various evolutionary pathways may coexist in galaxies, with merging events and dissipative collapse being the main mechanisms driving the formation of the most massive oblate bulges and bar evolution reshaping the less massive triaxial bulges.
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