•Effect of water in the diluent in supercritical fluid chromatography is investigated.•Compression of peaks is observed for early-eluting compounds.•Peaks eluting after water are broadened.•Adding ...water or formic acid to the mobile phase has little effect
In this study, the impact of introducing water in the sample solvent upon the injection in SFC is investigated. Adsorption of water on the stationary phase was indicated. Using a set of ten neutral test compounds and four ionizable test compounds, spread all along the co-solvent gradient, several parameters were scrutinized (i.e. water content in the sample diluent, nature of the sample diluent, nature of the co-solvent) in regards to peak broadening. From this systematic investigation, the competition for adsorption on the stationary phase between the analytes and the water molecules contained in the diluent was highlighted. The chromatographic peaks of neutral molecules eluting before water molecules were compressed and the ones eluting after were broadened. While the extent of this phenomenon was related to the peak position for neutral molecules, it was not observed on acidic molecules.
Although vaccination of pregnant women against influenza is recommended, the vaccination rate remains low. We conducted a study to identify determinants of influenza vaccination uptake in pregnancy ...in order to identify strategies to improve seasonal influenza vaccination rates.
Prospective observational hospital-based study in the French hospital performing the highest number of deliveries, located in the city of Lille, among all women who had given birth during the 2014-2015 influenza season. Data were collected through a self-completed questionnaire and from medical files. The vaccination uptake was self-reported. Determinants of vaccination uptake were identified using logistic regression analysis.
Of the 2045 women included in the study, 35.5% reported that they had been vaccinated against influenza during their pregnancy. The principal factors significantly associated with greater vaccination uptake were previous influenza vaccination (50.9% vs 20.2%, OR 4.1, 95% CI 3.1-5.5), nulliparity (41.0% vs 31.3%, OR 2.5, 95% CI 1.7-3.7), history of preterm delivery < 34 weeks (43.4% vs 30.3%, OR 2.3, 95% CI 1.1-4.9), the mother's perception that the frequency of vaccine complications for babies is very low (54.6% vs 20.6%, OR 1.1, 95% CI 0.5-2.2), the mother's good knowledge of influenza and its vaccine (61.7% vs 24.4%, OR 3.1, 95% CI 2.2-4.4), hospital-based prenatal care in their first trimester of pregnancy (55.0% vs 30.2%, OR 2.1, 95% CI 1.2-3.7), vaccination recommendations during pregnancy by a healthcare worker (47.0% vs 2.7%, OR 18.8, 95% CI 10.0-35.8), receipt of a vaccine reimbursement form (52.4% vs 18.6%, OR 2.0, 95% CI 1.5-2.7), and information from at least one healthcare worker about the vaccine (43.8% vs 19.1%, OR 1.8, 95% CI 1.3-2.6).
Our findings suggest that in order to increase flu vaccination compliance among pregnant women, future public health programmes must ensure cost-free access to vaccination, and incorporate education about the risks of influenza and the efficacy/safety of vaccination and clear recommendations from healthcare professionals into routine antenatal care.
Une revue de question sur l’expérience scolaire des élèves en situation de handicap, à l’appui d’enquêtes qualitatives et quantitatives, questionne les objectifs affichés des politiques de ...l’éducation inclusive. Ces études montrent une expérience ressentie plus favorablement en classe spécialisée, du fait d’un rapport à la scolarité détérioré en classe ordinaire et d’un sentiment d’isolement et d’incompétence développée face aux difficultés rencontrées. La recherche menée dans une ULIS-collège parcours bilingue LSF–français écrit, auprès d’élèves sourds et entendants scolarisés ensemble en classe ordinaire, laisse entendre d’autres récits. La manière dont sont conduites les situations scolaires et d’enseignement au sein de ce dispositif d’aide, engage chez ces élèves une expérience valorisante et capacitante, permettant d’occuper une place d’élève reconnue dans la classe et parmi les pairs. L’apprentissage de la LSF, le travail des traducteurs au niveau linguistique comme au niveau pédagogique et didactique, le rôle soutenant des systèmes didactiques auxiliaires, participent au processus d’accessibilisation des situations scolaires notamment à l’accessibilité didactique, ouvrant aux élèves un espace d’opportunité scolaire.
A review on the educational experience of students with disabilities, based on qualitative and quantitative surveys, questions the stated objectives of inclusive education policies. These studies show a more favourable experience in the specialized classe, due to a deteriorated relationship to schooling in the regular classroom and a sense of isolation and incompetence developed faced of difficulties. Research conducted in a bilingual French sign language-French written device, in secondary school with deaf and hearing students schooled together in the regular classroom, suggests other stories. The way in which school and teaching situations are conducted within this aid system, engages these students in a rewarding and capaciting experience, to be a recognized student in the classroom and among peers. Learning French sign language, the work of translators at the linguistic as well as pedagogical and educational level, the supporting role of auxiliary teaching systems, participate in the process of accessing school situations, especially to educational accessibility, thus providing students with a space of opportunity to attend school.
Muscotoxins are cyanobacterial cyclic lipopeptides with potential applications in biomedicine and biotechnology. In this study,
CCALA125 strain extracts were enriched by polymeric resin treatment, ...and subjected to HPCCC affording three cyclic lipopeptides (
⁻
), which were further repurified by semi-preparative HPLC, affording
,
, and
, with a purity of 86%, 92%, and 90%, respectively. The chemical identities of
⁻
were determined as muscotoxins A and B, respectively, by comparison with previously reported ESI-HRMS/MS data, whereas
was determined as a novel muscotoxin variant (muscotoxin C) using NMR and ESI-HRMS/MS data. Owing to the high yield (50 mg), compound
was broadly screened for its antimicrobial potential exhibiting a strong antifungal activity against
,
, and
, with minimum inhibitory concentration (MIC) values of 0.58, 2.34, and 2.34 µg/mL; respectively, and weak antibacterial activity against
with a MIC value of 37.5 µg/mL. Compounds
and
were tested only against the plant pathogenic fungus
due to their low yield, displaying a moderate antifungal activity. The developed chromatographic method proved to be an efficient tool for obtaining muscotoxins with potent antifungal properties.
The analysis of complex samples is facilitated by the emergence of two-dimensional liquid chromatography. Despite optimization efforts to reach tremendous peak capacities, the separation of neutral ...compounds remains limited. Indeed, most combinations of chromatographic modes suffer either from a lack of orthogonality or from serious solvent incompatibilities. The two-dimensional separation involving a combination of liquid chromatography and supercritical fluid chromatography seems to offer new opportunities for the separation of ionizable and neutral solutes. This review highlights the orthogonality the combination can offer thanks to a wide range of stationary phases. Injection effects occurring in SFC, that may drastically reduce the performances of online LC × SFC are also discussed in details. Finally, despite net improvement in SFC instrumentation in the recent years, instrumental limitations still have to be overcome. While this review highlights the potential of LC and SFC combination and its complementarity with 2D-LC, it also demonstrates that its development requires the joint efforts of researchers and instrumental suppliers before comprehensive LC × SFC gets adopted by the scientific community.
•The separation of neutral molecules is limited in LC × LC.•Two-dimensional LC × SFC or SFC × LC combinations exhibit interesting orthogonality for the separation of neutral molecules.•Injection effects in SFC are still under investigation.•Specific interfaces have been proposed but a commercial instrumentation is still lacking.
OBJECTIVE:The pathogenesis and the outcome of Pseudomonas aeruginosa ventilator-acquired pneumonia depend on the virulence factors displayed by the bacteria as well as the host response. Thus, quorum ...sensing, lipopolysaccharide, and type 3 secretion system have each individually been shown to be important virulence systems in laboratory reference strains. However, the relative contribution of these three factors to the in vivo pathogenicity of clinically relevant strains has never been studied. We analyzed the virulence of 56 nonclonal Pseudomonas aeruginosa strains isolated from critically ill patients with ventilator-acquired pneumonia. To avoid the variation of human immune response, we used a murine model of pneumonia. The aim was to determine which virulence factor was the most important.
SETTING:Research laboratory of a university.
SUBJECTS:Male adult BALB/c mice.
INTERVENTIONS:In vitro, the phenotype of each strain was established as to the expression of quorum sensing-regulated factors (elastase and pyocyanin), type 3 secretion system exotoxin secretion (Exotoxin U, S and/or T, or “nonsecreting”), and lipopolysaccharide O-antigen serotype. Strain pathogenicity was evaluated in vivo in a mouse model of acute pneumonia through lung injury assessment by measuring alveolar–capillary barrier permeability to proteins, lung wet/dry weight ratio, and bacterial dissemination. Associations were then sought between virulence system phenotypes and levels of lung injury.
MEASUREMENTS AND MAIN RESULTS:In univariate analysis, elastase production, O11 serotype, and type 3 secretion system exotoxin secretion were associated with increased lung injury and exotoxin U was linked to an increase risk of bacteremia. In multivariate analysis, we observed that type 3 secretion system exotoxin secretion and to a lesser degree elastase production were associated with increased lung injury.
CONCLUSION:In a murine model of pneumonia, our data suggest that type 3 secretion system and elastase are the most important virulence factors in clinically relevant P. aeruginosa strains.
Objective
High volume hemofiltration (HVHF) has shown potential benefits in septic animals and a few reports suggested a hemodynamic improvement in humans. However, randomized studies are still ...lacking. Our goal was to evaluate the hemodynamic effects of HVHF in septic shock patients with acute renal failure (ARF).
Design and setting
Prospective randomized study in an intensive care unit (ICU).
Patients
Twenty patients with septic shock and ARF.
Interventions
Patients were randomized to either high volume hemofiltration HVHF 65 ml/(kg h) or low volume hemofiltration LVHF 35 ml/(kg h). Vasopressor dose was adjusted to reach a mean arterial pressure (MAP) > 65 mmHg.
Measurements and results
We performed six hourly measurements of MAP, norepinephrine dose, PaO
2
/FiO
2
and lactate, and four daily urine output and logistic organ dysfunction (LOD) score. Baseline characteristics of the two groups were comparable on randomization. Mean norepinephrine dose decreased more rapidly after 24 h of HVHF treatment compared to LVHF treatment (
P
= 0.004) whereas lactate and PaO
2
/FiO
2
did not differ between the two treatment groups. During the 4-day follow-up, urine output was slightly increased in the HVHF group (
P
= 0.059) but the LOD score evolution was not different. Duration of mechanical ventilation, renal replacement therapy and ICU length of stay were also comparable. Survival on day 28 was not affected.
Conclusion
HVHF decreased vasopressor requirement and tended to increase urine output in septic shock patients with renal failure. However, a larger trial is required to confirm our results and perhaps to show a benefit in survival.
Cet article propose des résultats d’une recherche qui suit la mise en place du dispositif « devoirs-faits » dans un collège REP+ de Marseille, et qui associe des chercheurs avec des acteurs de ...terrain. Il tente de comprendre et de décrire les liens (explicites et / ou implicites) qui se tissent entre les séances de « devoirs-faits » proposées au sein du dispositif et les séances en classes entières. À travers l’analyse d’études de cas de séances relativement différentes, nous cherchons à modéliser les structures et les fonctions de ces systèmes didactiques auxiliaires (SDA) ainsi que les articulations qu’ils entretiennent ou non avec le travail en classe entière que nous nommons système didactique principal (SDP). Dans cet article, l’analyse mésogénétique menée (Sensevy et al ., 2000 ; Chevallard, 1992) aboutit à une proposition de trois modèles d’articulation possible entre SDA et SDP. Cette étude permet en outre de faire évoluer la catégorisation des objets de savoirs initialement proposée par Mercier (1995, 1996, 1999).
Despite widely disseminated guidelines, pneumococcal and influenza vaccination coverage (VC) remains insufficient in patients with cancer receiving cancer treatment. We performed an interventional ...study to evaluate VC in patients with cancer treated at the medical oncology departments of three North-of-France hospitals and to assess the effect of medical staff training on VC in these patients.
A standardized questionnaire assessed VC in adult patients with cancer receiving anticancer treatment at three day hospitals during December 2–7, 2019. Subsequently (January 2020), we organized educational training sessions for medical staff from each hospital to discuss the current vaccination guidelines. To assess the impact of training on pneumococcal and influenza VC, we re-administered the same questionnaire in March 2020. Because there are no specific guidelines on Diphtheria-Tetanus-Pertussis (DTP) vaccination and no improvement was expected, DTP VC acted as an internal control.
In total, 272 patients from all three hospitals were enrolled in the “before study”; 156 patients from only two hospitals were enrolled in the “after study” as medical training and data collection at the third were impossible because of administrative reasons and COVID-19 pandemic. The predictors were age for DTP VC; treatment center for pneumococcal VC; and age, sex, and tumor histology (adenocarcinoma vs. others) for influenza VC. Neither influenza VC (42.6% vs. 55.1%, p = 0.08), nor pneumococcal VC were significantly improved post-intervention (11.8% vs. 15.4%, p = 1). There seems to be a small effect in the most fragile for influenza VC.
As expected, VC was very low in patients with cancer, consistent with the literature. There was no impact of the intervention for pneumococcal and influenza VC.
PDF
