Implementation and evaluation of a paediatric nurse-driven sedation protocol in a paediatric intensive care unit

Background

Optimal sedation and analgesia is a challenge in paediatric intensive care units (PICU) because of difficulties in scoring systems and specific metabolism inducing tolerance and withdrawal. Excessive sedation is associated with prolonged mechanical ventilation and hospitalisation. Adult and paediatric data suggest that goal-directed sedation algorithms reduce the duration of mechanical ventilation. We implemented a nurse-driven sedation protocol in a PICU and evaluated its impact.

Methods

We conducted a before and after protocol implementation study in a population of children aged 0–18 years who required mechanical ventilation for at least 24 h between January 2013 and March 2015. After the protocol implementation in January 2014, nurses managed analgesia and sedation following an algorithm that included the COMFORT behaviour scale (COMFORT-B). Duration of mechanical ventilation was the primary outcome; secondary outcomes were total doses and duration of medications, PICU length of stay, incidence of ventilator-associated pneumonia, and occurrence of withdrawal symptoms. Pre–post analysis followed with segmented regression analysis of interrupted time series was used to assess the effect of protocol.

Results

A total of 200 children were analysed, including 107 before implementation and 93 children after implementation of the protocol. After implementation of the protocol, the total number of COMFORT-B scores per day of mechanical ventilation significantly increased from 3.9 ± 2.5 times during the pre-implementation period to 6.6 ± 3.5 times during the post-implementation period (p < 10⁻³). Mean duration of mechanical ventilation tended to be lower in the post-implementation period (8.3 ± 7.3 vs 6.6 ± 5.6 days, p = 0.094), but changes in either the trend per trimester from pre-implementation to post-implementation (p = 0.933) or the immediate change after implementation (p = 0.923) were not significant with segmented regression analysis. No significant change between pre- and post-implementation was shown for total dose of sedatives, withdrawal symptoms, agitation episodes, or unplanned endotracheal extubations.

Conclusions

These results were promising and suggested that implementation of a nurse-driven sedation protocol in a PICU was feasible. Evaluation of sedation and analgesia was better after the protocol implementation; duration of mechanical ventilation and occurrence of withdrawal symptoms tended to be reduced.

Electronic supplementary material

The online version of this article (doi:10.1186/s13613-017-0256-7) contains supplementary material, which is available to authorized users.

Randomized comparative evaluation of endoscopic submucosal dissection self-learning software in France and Japan

Background and study aim: Endoscopic submucosal dissection (ESD) is currently the reference method to achieve an en bloc resection for large lesions; however, the technique is difficult and risky, with a long learning curve. In order to reduce the morbidity, training courses that use animal models are recommended. Recently, self-learning software has been developed to assist students in their training. The aim of this study was to evaluate the impact of this tool on the ESD learning curve. Methods: A prospective, randomized, comparative study enrolled 39 students who were experienced in interventional endoscopy. Each student was randomized to one of two groups and performed 30 ESDs of 30 mm standardized lesions in a bovine colon model. The software group used the self-learning software whereas the control group only observed an ESD procedure video. The primary outcome was the rate of successful ESD procedures, defined as complete en bloc resection without any perforation and performed in less than 75 minutes. Results: A total of 39 students performed 1170 ESDs. Success was achieved in 404 (70.9 %) in the software group and 367 (61.2 %) in the control group (P = 0.03). Among the successful procedures, there were no significant differences between the software and control groups in terms of perforation rate (22 [4.0 %] vs. 29 [5.1 %], respectively; P = 0.27) and mean (SD) procedure duration (34.1 [13.4] vs. 32.3 [14.0] minutes, respectively; P = 0.52). For the 30th procedure, the rate of complete resection was superior in the software group (84.2 %) compared with the control group (50.0 %; P = 0.01). Conclusion: ESD self-learning software was effective in improving the quality of resection compared with a standard teaching method using procedure videos. This result suggests the benefit of incorporating such software into teaching programs.

Determinants of sick-leave length: still limited to diagnosis elements

PURPOSE

Sickness certification implies that a health problem impairs ability to work. However, its assessment is seldom performed by physicians. Our objective was, therefore, to assess the specific influence of functional and environmental limitations on the length of sick-leave prescriptions.

METHOD

We conducted a cross-sectional study in French general teaching practices and recorded 353 initial sick-leave certifications. For each of them, the functional and environmental limitations were collected using the ATCIF questionnaire, derived from the International Classification of Functioning. Data analysis was based on a linear regression multivariate model.

RESULTS

Among the functional limitations, "pain" was the main body function impairment (22% of impairments) and "mobility" the main activity limitation (48%). An environmental barrier was identified in 39% of sick-listed patients, mainly relating to "products and technology" (20%), which refers to workplace factors. The prescription was longer in cases of activity limitations relating to "mobility" and in cases of environmental barriers relating to "products and technology". The multivariate model explained 27% of the variability of sick-leave length through diagnosis elements and only 7% through functional and contextual elements.

CONCLUSION

In sick-leave prescription, a functional and contextual approach, in addition to the traditional diagnosis-based approach, could better support patients' shared understanding and follow-up, and accountability towards health authorities. Implication for Rehabilitation Although sickness certification implies that a health problem impairs ability to work, decision on sick-leave length in general practice is primarily based on diagnosis. A more functional and contextual approach could better support patients' and other health professionals' shared understanding and follow-up, and accountability towards health authorities. Such evolution requires a change of paradigm in medical education, and the way of reasoning of healthcare professionals.

Long-term effectiveness of an educational and physical intervention for preventing low-back pain recurrence: a randomized controlled trial

OBJECTIVE

Low-back pain (LBP) is a common and recurrent condition, but the evidence is scarce about effective strategies to prevent recurrence and disability in the longer term. This study investigated the effect of a light exercise program, initiated in the workplace and continued at home, in reducing recurrence of LBP episodes among healthcare workers.

METHODS

A total of 353 healthcare workers from ten hospitals were enrolled in a randomized controlled trial (RCT) and were randomized to the intervention or control groups, the latter of which received usual care. The intervention comprised three steps: (i) a 2-hour education session, (ii) five weekly 90-minutes exercise training sessions in the workplace, and (iii) a home-based self-managed exercise program. The main outcome was recurrence of LBP with sick-leave at 24-months follow-up.

RESULTS

At two-year follow-up, 35 workers (24%) in the intervention group and 31 workers (21%) in the control group had at least one LBP recurrence with sick leave. No effect was observed between groups [odds ratio (OR) 1.22, 95% confidence interval (95% CI) 0.67-2.23, P=0.516]. The intervention was effective in reducing fear avoidance with a mean reduction of -3.6 (95% CI -4.8- -2.4) points on the fear-avoidance beliefs questionnaire score for physical activity (FABQ-P) in the intervention group compared with -1.3 (95% CI -2.2- -0.3) points in the control group (P<0.05). It was also effective in improving muscle endurance with a mean increase of 13.9 (95% CI 3.3-24.5) minutes on the Sorensen test in the intervention group compared with -8.3 (95% CI-17.5-0.9) minutes in the control group (P<0.05). Healthcare utilization was reduced in the intervention group for painkillers, medical visits, imaging and outpatient physiotherapy.

CONCLUSION

It was not possible to conclude about the effectiveness of a light exercise program to reduce LBP recurrence episodes in the long-term in healthcare workers. However, it was effective to improve muscle endurance, and to reduce fear-avoidance beliefs and healthcare utilization. Further studies are necessary in order to identify effective interventions to reduce LBP recurrence and related sick-leaves.

Cluster randomized trial to evaluate the impact of team training on surgical outcomes

Background

The application of safety principles from the aviation industry to the operating room has offered hope in reducing surgical complications. This study aimed to assess the impact on major surgical complications of adding an aviation-based team training programme after checklist implementation.

Methods

A prospective parallel-group cluster trial was undertaken between September 2011 and March 2013. Operating room teams from 31 hospitals were assigned randomly to participate in a team training programme focused on major concepts of crew resource management and checklist utilization. The primary outcome measure was the occurrence of any major adverse event, including death, during the hospital stay within the first 30 days after surgery. Using a difference-in-difference approach, the ratio of the odds ratios (ROR) was estimated to compare changes in surgical outcomes between intervention and control hospitals.

Results

Some 22 779 patients were enrolled, including 5934 before and 16 845 after team training implementation. The risk of major adverse events fell from 8·8 to 5·5 per cent in 16 intervention hospitals (adjusted odds ratio 0·57, 95 per cent c.i. 0·48 to 0·68; P &lt; 0·001) and from 7·9 to 5·4 per cent in 15 control hospitals (odds ratio 0·64, 0·50 to 0·81; P &lt; 0·001), resulting in the absence of difference between arms (ROR 0·90, 95 per cent c.i. 0·67 to 1·21; P = 0·474). Outcome trends revealed significant improvements among ten institutions, equally distributed across intervention and control hospitals.

Conclusion

Surgical outcomes improved substantially, with no difference between trial arms. Successful implementation of an aviation-based team training programme appears to require modification and adaptation of its principles in the context of the the surgical milieu. Registration number: NCT01384474 (http://www.clinicaltrials.gov).

Dolutegravir as monotherapy in HIV-1-infected individuals with suppressed HIV viraemia

BACKGROUND

Reducing drug burden is a key challenge for achieving lifelong suppressive HIV therapy. Dolutegravir, with a high potency, long half-life and high genetic barrier, offers potential for monotherapy.

METHODS

This observational single-centre study enrolled all patients with HIV RNA (viral load) <50 copies/mL for at least 12 months, with CD4 >350 cells/mm(3) and with no failure under integrase inhibitor therapy who had switched from suppressive ART to dolutegravir monotherapy (50 mg/day). Primary outcome was proportion of patients with viral load <50 copies/mL at week 24.

RESULTS

Twenty-eight patients treated for a median ART duration of 17 years (IQR 11-20), virally suppressed for a median of 79 months (IQR 42-95) and with a median CD4 count of 624 cells/mm(3) (IQR 524-761), were enrolled. Baseline ART consisted of a three-drug (n = 10), two-drug (n = 10) or single-drug (n = 8) regimen with integrase inhibitor exposure in 13 patients. The proportion of patients maintaining viral load <50 copies/mL was 96% (95% CI 79%-100%) at week 4, 100% (95% CI = 85%-100%) at week 8, 93% (95% CI 76%-99%) at week 12 and 92% (75-99) at week 24. Three patients (3.70%; 95% CI 3.4%-10.8%) with prior integrase inhibitor experience had HIV RNA rebound with the presence of resistance mutations. Genotyping of HIV DNA using the Sanger method or ultradeep sequencing showed no integrase inhibitor resistance-associated mutations (RAMs) except for the mutation 74I in a patient on a suppressive elvitegravir regimen. The median within- and between-subject variability of dolutegravir C24 was 25% and 34%, respectively. Nine patients with a year of follow-up remained virally suppressed.

CONCLUSIONS

Dolutegravir has the potency to be further investigated as a single ART in randomized studies, particularly in patients with no prior exposure to integrase inhibitors.

Effectiveness of a nurse educational oral feeding programme on feeding outcomes in neonates: protocol for an interrupted time series design

INTRODUCTION

Oral feeding is a complex physiological process. Several scales have been developed to assess the ability of the neonate to begin suck feedings and assist caregivers in determining feeding advancement. However, feeding premature neonates remains an ongoing challenge and depends above all on caregivers' feeding expertise. We will evaluate the effect of a nurse training programme on the achievement of full oral feeding with premature neonates.

METHODS AND ANALYSIS

The study design will be an interrupted time series design with 3 phases: (1) A 6-month baseline period; (2) a 22-month intervention period and (3) a 6-month postintervention period. The intervention will consist of an educational programme, for nurses and assistant nurses, on feeding patterns in neonates. The training modules will be composed of a 2-day conference, 2 interactive multidisciplinary workshops, and routine practice nurse coaching. A total of 120 nurses and 12 assistant nurses, who work at the neonatal unit during the study period, will participate in the study. All premature neonates of <34 weeks postmenstrual age (PMA) will be included. The primary outcome will be the age of tube withdrawal PMA and chronological age are taken into account. The secondary outcomes will be the transition time, length of hospital stay, competent suckle feeding without cardiorespiratory compromise, rate of neonates presenting with feeding issues or feeding rejection signs, and current neonatal pathologies or deaths during hospital stay. A segmented regression analysis will be performed to assess the impact of the programme.

ETHICS AND DISSEMINATION

Approval for the study was obtained from the Hospital Ethics Committee, and the Institutional Review Board, as well as the French Data Protection Agency. The findings from the study will be disseminated through peer-reviewed journals, national and international conference presentations and public events.

TRIAL REGISTRATION NUMBER

NCT02404272 (https://clinicaltrials.gov).

Trends of labile trace metals in tropical urban water under highly contrasted weather conditions

The spatio-temporal trend of trace metals (Cd, Co, Cr, Cu, Ni, Pb, and Zn) in a tropical urban estuary under the influence of monsoon was determined using diffusive gradient in thin films (DGT) in situ samplers. Three different climatic periods were observed: period 1, dry with dredging activity; period 2, intermediate meaning from dry to wet event; and period 3, wet having continuous rainfall. Conforming to monsoon regimes, these periods correspond to the following: transition from winter to summer, winter, and summer monsoons, respectively. The distinction of each period is defined by their specific hydrological and physico-chemical conditions. Substantial concentrations of the trace metals were detected. The distribution and trend of the trace metals under the challenge of a tropical climate were able to follow using DGT as a sensitive in situ sampler. In order to identify the differences among periods, statistical analyses were performed. This allowed discriminating period 2 (oxic water) as significantly different compared to other periods. The spatio-temporal analysis was then applied in order to distinguish the trend of the trace metals. Results showed that the trend of trace metals can be described according to their response to (i) seasonal variations (Cd and Cr), (ii) spatio-temporal conditions (Co, Cu, Ni, and Pb), and (iii) neither (i) nor (ii) meaning exhibiting no response or having constant change (Zn). The correlation of the trace metals and the physico-chemical parameters reveals that Cd, Co, Cu, and Cr are proportional to the dissolved oxygen (DO), Cd and Ni are correlated pH, and Zn lightly influenced by salinity.

Implementation of a computerized system in pediatric wards to improve nutritional care: a cluster randomized trial

BACKGROUND/OBJECTIVES

Malnutrition occurs frequently in hospitalized children. We aimed to assess whether a computerized system could lead to improved clinical practices in malnourished children.

SUBJECTS/METHODS

Healthcare workers (242) from six departments in a pediatric university hospital participated in a cluster randomized trial, studying 1457 malnourished children hospitalized from September 2009 to August 2011. Following a baseline observational pre-intervention period, all departments were randomized into either intervention or control arms. A computerized malnutrition-screening system was implemented in the intervention group to automatically trigger a dietetic referral in real time. Furthermore, the nutrition support team conducted an awareness campaign with healthcare workers and a leadership-based strategy to reinforce the message during the entire study period. Adherence to practice guidelines (daily weights, investigation of etiology for malnutrition, management by a dietitian and application of refeeding protocols) was compared between pre- and post-intervention periods in both the intervention and trial arms.

RESULTS

When compared with the pre-intervention period, the clinical practices were significantly improved within the intervention arm for every outcome (P<0.01), whereas remained unchanged in the control arm. In addition, during the post-intervention period, malnutrition etiology investigation by physicians (adjusted odds ratio (OR) of 4.4, 95% confidence interval (CI) 1.7-11.8, P=0.003) and management by a dietitian (OR 2.7, 95% CI 1.0-6.9, P=0.046) occurred more frequently in the intervention clusters.

CONCLUSIONS

Implementation of an electronic system to detect malnutrition in real time was associated with a rapid improvement in clinical practices for better care of hospitalized children.

Perineal retraining improves conservative treatment for faecal incontinence: a multicentre randomized study

BACKGROUND

Anal incontinence is a frequent complaint that profoundly affects quality of life. Our aim was to determine whether perineal retraining gives additional benefits to standard medical treatment.

METHODS

Patients with anal incontinence and a Wexner score >4 were randomly assigned to standard conservative treatment (control) or perineal retraining, including biofeedback, in addition to standard treatments (biofeedback). Diaries, self-administered questionnaires and satisfaction scores quantified the benefits. Self-evaluated improvement was the primary outcome measure. A score ≥3 (in an improvement scale from -5 to +5) defined success.

RESULTS

Overall, 157 patients were included; 80 in the control group (75% females, mean age 60.1 ± 13.2 years) and 77 in the biofeedback group (79% females, mean age 61.9 ± 10.2 years). After a 4-month follow-up, the success rate was significantly higher in the biofeedback group (57% versus 37%; p<0.021). In the biofeedback group, daily stool frequency, leakage, and faecal urgency significantly decreased, and daily non-urgent perception of stool increased. Conversely, symptomatic scores and quality of life scales did not significantly differ between groups. In a multivariate model, the adjusted odds ratio showed that perineal retraining was significantly associated with a higher chance of self-rated improvement (adjusted Odd Ratio [95%CI]: 2.34 [1.14-4.80]; p=0.021).

CONCLUSIONS

Perineal retraining offers a moderate but significant benefit for patients suffering from anal incontinence.

Multifaceted intervention to enhance the screening and care of hospitalised malnourished children: study protocol for the PREDIRE cluster randomized controlled trial

BACKGROUND

Hospital malnutrition is an underestimated problem and as many as half of malnourished patients do not receive appropriate treatment. In order to extend the management of malnutrition in health care facilities, multidisciplinary teams focusing on clinical nutrition were established in France. The establishment of such teams within hospital facilities remains nonetheless difficult. We have consequently developed a multifaceted intervention coordinated by a Nutritional Support Team (NST). Our study aims to evaluate the impact of this multifaceted intervention coordinated by a NST, in adherence to recommended practices for the care of malnourished children, among health care workers of a paediatric university hospital.

METHODS/DESIGN

We carried out 1) a six-month observational phase focusing on the medical care procedures relative to malnourished children followed by 2) a cluster randomised controlled trial phase to evaluate the impact of a multidisciplinary nutrition team over an 18 month time frame.Based on power analyses and assuming a conservative intracluster correlation coefficient, 1289 children were needed to detect a 25% difference in rates between the two groups of the cluster trial.The implementation of our intervention was coordinated by the NST and had three major components: a) access to a computerised malnutrition screening system associated with an automatic alert system, b) an awareness campaign directed toward the health care workers and c) a leadership based strategy.Main outcomes included the number of daily weighings during hospitalisation, the investigation of malnutrition etiology and the management of malnutrition by a dietician and/or the NST.Due to the clustered nature of the data with children nested in departments, a generalized estimated equations approach will be used to analyse the impact of the multifaceted intervention on primary and secondary outcomes.

DISCUSSION

Our results will provide an overall response regarding the effectiveness of our multifaceted intervention and we should be able to suggest an organization and mode of operation of NST.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT01081587.

Prevalence, characteristics, and prognosis role of type 1 ST elevation in the peripheral ECG leads in patients with Brugada syndrome

BACKGROUND

Despite isolated reports of Brugada syndrome (BrS) in the inferior or lateral leads, the prevalence and prognostic value of ST elevation in the peripheral electrocardiographic (ECG) leads in patients with BrS remain poorly known.

OBJECTIVE

To study the prevalence, characteristics, and prognostic value of type 1 ST elevation and ST depression in the peripheral ECG leads in a large cohort of patients with BrS.

METHODS

ECGs from 323 patients with BrS (age 47 ± 13 years; 257 men) with spontaneous (n = 141) or drug-induced (n = 182) type 1 ECG were retrospectively reviewed. Two hundred twenty-five (70%) patients were asymptomatic, 72 (22%) patients presented with unexplained syncope, and 26 (8%) patients presented with sudden death (12 patients) or appropriated implantable cardioverter-defibrillator therapies (14 patients) at diagnosis or over a mean follow-up of 48 ± 34 months.

RESULTS

Thirty (9%) patients presented with type 1 ST elevation in at least 1 peripheral lead (22 patients in the aVR leads, 2 in the inferior leads, 5 in both aVR and inferior leads, and 1 in the aVR and VL leads). Patients with type 1 ST elevation in the peripheral leads more often had mutations in the SCN5A gene, were more often inducible, had slower heart rate, and higher J-wave amplitude in the right precordial leads. Twenty-seven percent (8 of 30) of the patients with type 1 ST elevation in the peripheral leads experimented sudden death/appropriate implantable cardioverter-defibrillator therapy, whereas it occurred in only 6% (18 of 293) of other patients (P < .0001). In multivariate analysis, type 1 ECG in the peripheral leads was independently associated with malignant arrhythmic events (odds ratio 4.58; 95% confidence interval 1.7-12.32; P = .0025).

CONCLUSIONS

Type 1 ST elevation in the peripheral ECG leads can be seen in 10% of the patients with BrS and is an independent predictor for a malignant arrhythmic event.

The PRESLO study: evaluation of a global secondary low back pain prevention program for health care personnel in a hospital setting. Multicenter, randomized intervention trial

Background

Common low back pain represents a major public health problem in terms of its direct cost to health care and its socio-economic repercussions. Ten percent of individuals who suffer from low back pain evolve toward a chronic case and as such are responsible for 75 to 80% of the direct cost of low back pain. It is therefore imperative to highlight the predictive factors of low back pain chronification in order to lighten the economic burden of low back pain-related invalidity. Despite being particularly affected by low back pain, Hospices Civils de Lyon (HCL) personnel have never been offered a specific, tailor-made treatment plan. The PRESLO study (with PRESLO referring to Secondary Low Back Pain Prevention, or in French, PREvention Secondaire de la LOmbalgie), proposed by HCL occupational health services and the Centre Médico-Chirurgical et de Réadaptation des Massues – Croix Rouge Française, is a randomized trial that aims to evaluate the feasibility and efficiency of a global secondary low back pain prevention program for the low back pain sufferers among HCL hospital personnel, a population at risk for recurrence and chronification. This program, which is based on the concept of physical retraining, employs a multidisciplinary approach uniting physical activity, cognitive education about low back pain and lumbopelvic morphotype analysis. No study targeting populations at risk for low back pain chronification has as yet evaluated the efficiency of lighter secondary prevention programs.

Methods/Design

This study is a two-arm parallel randomized controlled trial proposed to all low back pain sufferers among HCL workers, included between October 2008 and July 2011 and followed over two years. The personnel following their usual treatment (control group) and those following the global prevention program in addition to their usual treatment (intervention group) are compared in terms of low back pain recurrence and the impairments measured at the beginning and the end of the study. The global prevention program is composed of a two-hour information session about low back pain and pain pathways, followed by five weekly 90-min exercise sessions with one physiotherapist per group of eight to ten personnel. A booklet for home use with patient-managed exercise instructions and information (The Back Book) is given to each participant at the end of the program.

An X-ray assessment of the entire spinal column of each participant (in both the control and intervention groups) is performed at the onset of the study in order to analyze sagittal spinopelvic balance as well as lombopelvic morphotype.

Discussion

The results of this study, which is innovative and unique in France, will be available in 2014 and will make it possible to draw conclusions regarding the program’s impact on the risk of recurrence and chronification of low back pain.

Trial registration

http://www.clinicaltrials.gov # NCT00782925

A French observational study of botulinum toxin use in the management of children with cerebral palsy: BOTULOSCOPE

BACKGROUND

Dystonia and spasticity are common symptoms in children with Cerebral Palsy (CP), whose management is a challenge to overcome in order to enable the harmonized development of motor function during growth.

AIM

To describe botulinum toxin A (BTX-A) use and efficacy as a treatment of focal spasticity in CP children in France.

METHODS

This prospective observational study included 282 CP children mostly administered according to French standards with BTX-A in lower limbs. Realistic therapeutic objectives were set with parents and children together before treatment initiation and assessed using the Visual Analogue Scale (VAS). Child management was recorded and the efficacy of injections was assessed during a 12-month follow-up period by physicians (Modified Ashworth Scale, joint range of motion, Physician Rating Scale, Gillette Functional Assessment Questionnaire and Gross Motor Function Measure-66) and by patients/parents (Visual Analogue Scale).

RESULTS

BTX-A treatment was administered in different muscle localizations at once and at doses higher than those recommended by the French Health Authorities. Children were treated in parallel by physiotherapy, casts and ortheses. Injections reduced spasticity and improved joint range of motion, gait pattern and movement capacity. Pain was reduced after injections. BTX-A administration was safe: no botulism-like case was reported. The log of injected children who were not included in the study suggested that a large population could benefit from BTX-A management.

CONCLUSIONS

We showed here the major input of BTX-A injections in the management of spasticity in CP children. The results are in favor of the use of BTX-A as conservative safe and efficient treatment of spasticity in children, which enables functional improvement as well as pain relief.

A high sensitivity ultralow temperature RF conductance and noise measurement setup

We report on the realization of a high sensitivity RF noise measurement scheme to study small current fluctuations of mesoscopic systems at milli-Kelvin temperatures. The setup relies on the combination of an interferometric amplification scheme and a quarter-wave impedance transformer, allowing the measurement of noise power spectral densities with gigahertz bandwidth up to five orders of magnitude below the amplifier noise floor. We simultaneously measure the high frequency conductance of the sample by derivating a portion of the signal to a microwave homodyne detection. We describe the principle of the setup, as well as its implementation and calibration. Finally, we show that our setup allows to fully characterize a subnanosecond on-demand single electron source. More generally, its sensitivity and bandwidth make it suitable for applications manipulating single charges at GHz frequencies.

[High resolution MR imaging of the skin: normal imaging features]

PURPOSE

To describe the qualitative and quantitative MR imaging features of normal skin.

MATERIALS AND METHODS

Thirty-one normal subjects underwent MR evaluation on a 1.5 Tesla magnet using a dedicated coil. Several skin sites were evaluated (back at the scapular level, posterior calf and inferior heel). Two pulse sequences were acquired: a SE T1W and a gradient-echo sequence (FIESTA). Qualitative and quantitative analysis was performed for all three sites.

RESULTS

In normal subjects, the different skin layers (callus, epidermis, dermis, hypodermis and pilosebaceous follicles) can be separated and measured on MR. Epidermis and hypodermis are hyperintense whereas dermis is hypointense. Our results confirm the presence of qualitative and quantitative variations between different skin regions. In some cases, a differentiation between papillary and reticular dermis can be achieved. Pilosebaceous follicles and the deep vascular network were clearly depicted on the FIESTA sequence. Measurements for each skin layer were compared based on sex, site and MR pulse sequence.

CONCLUSION

MRI provides evaluation of the different skin layers, epidermis, dermis, and hypodermis, and their different components.

[Shoulder radiography: useful radiographic views in current practice]

The purposes of this paper are: 1) to review the different radiographic projections commonly used to explore shoulder pathology; 2) to propose a practical approach for radiographic evaluation of the shoulder, adapted to the main clinical situations; 3) to recognize the different imaging features of the most frequent shoulder diseases.

Discovery of new Gram-negative antivirulence drugs: structure and properties of novel E. coli WaaC inhibitors

Heptosyltransferases such as WaaC represent promising and attractive targets for the discovery of new Gram-negative antibacterial drugs based on antivirulence mechanisms. We report herein our approach to the identification of the first micromolar inhibitors of WaaC and the preliminary SAR generated from this family of 2-aryl-5-methyl-4-(5-aryl-furan-2-yl-methylene)-2,4-dihydro-pyrazol-3-ones identified by virtual screening.

Influenza burden in febrile infants and young children in a pediatric emergency department

BACKGROUND

In France, epidemiologic data in children in ambulatory settings are scarce. We aimed to measure the burden of influenza in young children.

METHODS

Febrile children younger than 36 months were consecutively recruited in a pediatric emergency department during the 2002 epidemic peak. Virology analysis and follow-up were systematic.

RESULTS

During calendar weeks 3 to 6, 2002, 575 children were recruited; 49% were positive: A/H3N2 in 44% and B in 5%. Prevalence rate was 57% in 12- to 35-month-old children and 39% in infants younger than 12 months. The main clinical pictures were nonrespiratory in one third of them. One of 8 patients had a complication. One of 10 patients was hospitalized, and the estimated specific hospitalization rate for the study period was 237 of 100,000 in the general population among infants younger than 12 months. Forty-two percent of children (n = 110) were prescribed antibiotics and at least 34% of them were inappropriate (n = 89). Median length of disease was 8 days, and 25% of the children had not fully recovered by day 11. Only one child had been previously vaccinated of 65 with chronic conditions. Both epidemic strains were covered by the vaccine.

CONCLUSIONS

Health outcomes showed that influenza disease burden in young French children is similar to that observed in North America. An active vaccination strategy would have strongly reduced the burden of influenza and lowered antibiotic use. Continuous efforts are needed to reach requirements of our influenza vaccination policy.

A new long-chain UV absorber derived from 4-tert-butyl-4'-methoxydibenzoylmethane: absorbance stability under solar irradiation

A new UV filter, the 1-(4-tert-butylphenyl)-2-decanyl-3-(4'-methoxyphenyl)-propane 1,3-dione called C10-DBM, was prepared by grafting a ten-carbon aliphatic chain to the alpha-carbonyl position of 4- tert -butyl-4'-methoxydibenzoylmethane (BM-DBM).(1) UVA absorption efficiency of a cosmetic preparation containing this new filter, called C10-DBM, was tested and compared to an identical preparation containing BM-DBM. The two preparations were irradiated under a 150-W xenon lamp or exposed to natural sunlight. The originality of this new filter resided in that its UVA absorbance appeared during the irradiation of the molecule. Moreover, although the molar absorption coefficient of C10-DBM in the UVA domain was lower than that of BM-DBM, its absorption showed much more photostable behavior under both methods of irradiation. After two hours of sunlight exposure, the preparation containing the BM-DBM lost 85% of its UVA absorbance, whereas the UVA absorbance of the preparation containing C10-DBM showed a decrease of 3% in comparison to the maximum absorbance obtained after 30 minutes of irradiation. Also, after two hours of exposure to natural sunlight, the UVA absorbance of the preparation containing C10-DBM remained above its initial value (before the irradiation began).

Comparative expression of vascular endothelial growth factor family members, VEGF-B, -C and -D, by normal human keratinocytes and fibroblasts

The vascular endothelial growth factor (VEGF) family includes the related polypeptides VEGF-B, -C and -D, which contribute to endothelial and lymphatic vessel development. The parental VEGF molecule, VEGF-A, has been widely described in the skin, but the other members of the VEGF family have not yet been reported. The aim of our study was to determine whether the two main skin cells, keratinocytes and fibroblasts, expressed VEGF-B, -C and -D in basal condition and after stimulation by either growth factors or the pro-inflammatory cytokine tumour necrosis factor-alpha (TNF-alpha). Reverse-transcription polymerase chain reaction (RT-PCR) analysis on cultured normal human keratinocytes (NHKs) and normal human fibroblasts (NHFs) allowed the detection of different levels of VEGF-B, -C and -D mRNA, in both cell types with similar RT-PCR products in the skin cells. A semi-quantitative evaluation of the VEGF family proteins by dot blot, using the different human recombinant VEGFs, showed different levels of VEGF-B, -C and -D, in NHKs and NHFs. After cell stimulation by growth factors (epidermal growth factor (EGF) and transforming growth factor-beta1 (TGF-beta1) for NHKs and NHFs, respectively), a significant up-regulation of the VEGF family member proteins was observed in NHFs but not in NHKs. Conversely, TNF-alpha did not exert a significant effect. However, we could not detect any transcriptional modification in stimulated cells, whatever the stimulation duration. The addition of cycloheximide to the cell cultures strongly inhibited the increase of VEGF proteins in TGF-beta1-stimulated NHFs. Taken together, the results underline the major role played by NHFs in the elaboration of the VEGF family proteins known to regulate wound healing, chronic inflammation and tumour angiogenesis and lymphangiogenesis.