High-responsivity operation of quantum cascade detectors at 9 µm.

Quantum cascade detectors (QCDs) are devices operating at zero external bias with a low dark-current. They show linear detection and high saturation intensities, making them suitable candidates for heterodyne detection in long-wave infrared (LWIR) free space optical communication systems. We present an approach to mitigate the performance limitation at long wavelengths, by a comparison of similar single and multi-period QCDs for optimizing their responsivity and noise behaviour. Our InGaAs/InAlAs/InP ridge QCDs are designed for operation at λ = 9.124 µm. Optical waveguide simulations support the accurate optical characterization. A detailed device analysis reveals room-temperature responsivities of 111 mA/W for the 15-period and 411 mA/W for the single-period device.

Spot urine collection: A valid alternative to total urine collection for metabolomic studies in dairy cattle.

Urine is a highly suitable biological matrix for metabolomics studies. Total collection for 24-h periods is the gold standard as it ensures the presence of all metabolites excreted throughout the day. However, in animal studies, it presents limitations related to animal welfare and also due to alterations of the metabolome originating from the use of acid for preventing microbial growth or microbial contamination. In this study, we investigated whether spot urine collection is a practical alternative to total collection for metabolomic studies in lactating cows. For this purpose, we collected urine samples from 4 lactating Holstein cows fed 4 diets in a 4 × 4 Latin square design. Urine was collected for 24 h using a collecting device (i.e., total collection) or collected once per day 4 h after the morning feeding (i.e., spot urine collection). Dietary treatments differed by the amount of nitrogen content (high vs. low) and by the nature of the energy (starch vs. fiber). Urine metabolome was analyzed by 2 untargeted complementary methods, nuclear magnetic resonance and hydrophilic-interaction liquid chromatography (HILIC) coupled to a time-of-flight mass spectrometer, and by 1 targeted method, HILIC-tandem mass spectrometry. Although sampling technique had an effect on the abundance of metabolites detected, spot urine samples were equally capable of showing differences in urine metabolome than samples from total collection. When considering nitrogen levels in the diet, the robustness and precision for discriminating high- and low-nitrogen diets was equally achieved with both sampling techniques. A total of 22 discriminant metabolites associated with the N level of diets were identified from untargeted HILIC coupled to a time-of-flight mass spectrometer (n = 9) and nuclear magnetic resonance (n = 11), and 2 from targeted HILIC-tandem mass spectrometry. Alternatively, starch or fiber in the diet induced less changes in the metabolome that were not clearly discriminated independently of the sampling technique. We concluded that spot urine collection can successfully reveal differences in the urine metabolome elicited by dietary N levels and be used as a substitute of total urinary 24-h collection for metabolomic studies.

Early life dietary intervention in dairy calves results in a long-term reduction in methane emissions.

Recent evidence suggests that changes in microbial colonization of the rumen prior to weaning may imprint the rumen microbiome and impact phenotypes later in life. We investigated how dietary manipulation from birth influences growth, methane production, and gastrointestinal microbial ecology. At birth, 18 female Holstein and Montbéliarde calves were randomly assigned to either treatment or control (CONT). Treatment was 3-nitrooxypropanol (3-NOP), an investigational anti-methanogenic compound that was administered daily from birth until three weeks post-weaning (week 14). Samples of rumen fluid and faecal content were collected at weeks 1, 4, 11, 14, 23, and 60 of life. Calves were tested for methane emissions using the GreenFeed system during the post-weaning period (week 11-23 and week 56-60 of life). Calf physiological parameters (BW, ADG and individual VFA) were similar across groups throughout the trial. Treated calves showed a persistent reduction in methane emissions (g CH4/d) throughout the post-weaning period up to at least 1 year of life, despite treatment ceasing three weeks post-weaning. Similarly, despite variability in the abundance of individual taxa across weeks, the rumen bacterial, archaeal and fungal structure differed between CONT and 3-NOP calves across all weeks, as visualised using sparse-PLS-DA. Similar separation was also observed in the faecal bacterial community. Interestingly, despite modest modifications to the abundance of rumen microbes, the reductive effect of 3-NOP on methane production persisted following cessation of the treatment period, perhaps indicating a differentiation of the ruminal microbial ecosystem or a host response triggered by the treatment in the early development phase.

Parental acceptance of an intranasal vaccine: Example of influenza vaccine.

BACKGROUND: Influenza vaccination coverage of children with chronic disease is insufficient in France, although a nasal live attenuated influenza vaccine (LAIV) has been approved. OBJECTIVE: We aimed to evaluate the acceptance of nasally administered vaccines by parents of children with chronic illness, by comparing LAIV vs. injectable inactivated influenza vaccine (IIV) acceptance. METHODS: We performed a retrospective, observational study (December 2014 to April 2015) including parents of all children vaccinated with the LAIV during the 2013-2014 influenza vaccination campaign at our university hospital. It was an opinion survey on the tolerance and acceptance of the LAIV. RESULTS: A standardized evaluation form was completed by 67/79 parents of all children who received the LAIV (mean age: 113±56 months; 64% with a chronic respiratory disease). The parents responded that vaccines in general were important (99%) but only 58% of them accepted the injectable route of administration. Of the 48 parents of children who had received both LAIV and IIV in the past, global opinion (P<0.0001) and tolerance (P<0.0001) were better for LAIV. For the future, 81% of parents would prefer LAIV, mainly because of needle absence and/or less painful character, and 18% IIV, mainly because of easier administration or habit. CONCLUSION: The better acceptance of a nasally administrated vaccine could increase vaccination coverage in the future for nasal vaccines.

Impact of the Sofia® Influenza A+B FIA rapid diagnostic test in a pediatric emergency department.

OBJECTIVE: The objective of this study was to evaluate the impact of a rapid diagnostic test for influenza (the Sofia® Influenza A+B FIA rapid diagnostic test [RDT]) in a pediatric emergency department (PED). METHODS: A retrospective, observational, cross-sectional study was conducted in the PED of the Lille University Hospital between 2013 and 2015. All patients under 18 years of age for whom influenza RDT was administered were included. Clinical data, management, and related hospitalizations were compared between positive and negative RDT groups. The length of stay in the PED (main outcome) and the number of additional tests (biological and radiographic tests) between the two groups were compared. RESULTS: A total of 238 tests were reported: 119 positive, 110 negative, nine invalid. The mean length of stay in the PED was significantly lower in the positive RDT group: 4.0h vs. 7.4h (P<10-6). Patients with positive RDT had significantly fewer biological tests (20% vs. 56%; P<10-7) and radiographs (23% vs. 52%; P<10-5). The prevalence of hospitalizations in a short-stay unit was significantly lower in patients with positive RDT (0.8% vs. 9.1%; P=0.009). CONCLUSIONS: This study showed a significant medical impact of the use of Sofia® Influenza RDT A+B FIA in a PED regarding the length of stay and the number of additional explorations.

Extended-spectrum ß-lactamase-producing Enterobacteriaceae, national study of antimicrobial treatment for pediatric urinary tract infection.

OBJECTIVE: To evaluate clinical practices for ESBL-producing urinary tract infection (UTI) in France. METHODS: We performed an observational, retrospective, cross-sectional, hospital-based study in 22 pediatric departments of university or secondary care hospitals. We collected data of the last five patients presenting with ESBL-producing UTI in 2012 and the physicians' therapeutic approach to two case vignettes of acute non-septic ESBL-producing pyelonephritis (7-month-old girl) and cystitis (30-month-old girl). The adequacy of the therapeutic decision was analyzed by a panel of independent infectious disease experts. RESULTS: A total of 80 case patients of ESBL-producing UTI were collected: 54 with acute pyelonephritis (mean age: 28 months, female: 66%), of whom 98% received an intravenous ESBL-adapted antibiotic treatment and 55% a two-drug antibiotic therapy. Carbapenems were used in 56% of cases and aminoglycosides in 36%. Of the 26 cystitis patients (mean age: 5 years, female: 73%), 85% were treated with antibiotics, including three intravenously (carbapenems=2). For the case vignettes, physicians (n=85) would have treated the pyelonephritis patient with carbapenems (76%) and/or aminoglycosides (68%); 71% would have used a two-drug antibiotic treatment. The cystitis patient would have been treated intravenously by 29% of physicians; 8% would have used a two-drug antibiotic treatment, 16% would have prescribed carbapenems, and 11% aminoglycosides. Antibiotic treatments were deemed appropriate in 37% of cases. CONCLUSIONS: Antimicrobial treatment for ESBL-producing UTI greatly varies, and carbapenems are excessively prescribed. Specific guidelines for ESBL infections are required.

Impact of the 13-valent pneumococcal conjugate vaccine on the incidence of pneumococcal meningitis in children.

The impact of the 13-valent pneumococcal conjugate vaccine (PCV13) on the incidence of pneumococcal meningitis (PM) in children is unknown. To determine this impact, a descriptive multicentre retrospective cohort study was conducted from 2008 to 2013 in northern France. All laboratory-confirmed PM in children aged <18 years in all hospitals of the area with paediatric units were included. Two independent databases were used for exhaustive identification of cases: medical plus laboratory records at each hospital and discharge codes. The corrected incidence of PM was determined by a capture-recapture analysis using these two databases. Sixty-two cases were found over the 6-year period. A decrease of the PM corrected incidence was observed in the global population (P = 0·07), significant only for children aged <2 years, from 11·9/100 000 in 2008 in 1·9/100 000 in 2013 [6·4 fold-decrease, 95% confidence interval (CI) 1·4-41, P = 0·01] between years 2008 and 2013. When comparing the pre- and post-PCV13 periods, this decrease was still statistically significant for children aged <2 years [7·32/100 000 (95% CI 4·39-10·25) to 2·78/100 000 (95% CI 0·96-4·60), P = 0·01]. Only three (5%) cases of PM caused by vaccine serotypes could have been prevented. After the introduction of the PCV13 vaccine, a decrease in the incidence of PM cases in children in northern France was observed.

[Management of urinary tract infections in children. Evaluation of clinical practice]. / Évaluation des pratiques de prise en charge des infections urinaires de l'enfant.

OBJECTIVE: To determine the rate of therapeutic management satisfying the institutional protocol for children with urinary tract infection (UTI) in the context of the emergence of extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae. METHODS: A retrospective, single-center, observational study was carried out for 1 year (2010-2011). Data from all children admitted to the emergency department with a diagnosis of UTI were analysed. Adherence to the protocol was evaluated for the initial management and at re-evaluation with the definitive result of the urine culture. Risk factors for nonadherence were analysed. RESULTS: Among the children, 393 were included. An ESBL Enterobacteriaceae-related UTI was identified in 2.2% of urine analyses. The initial therapeutic management satisfied the protocol for 95% of children and at re-evaluation for 80%. Nonadherence was related to poorly adapted treatment (59%) and an erroneous indication of dual antibiotic therapy (20%). Variables associated with the inadequacy of the initial management were age less than 3 months (adjusted OR [aOR]: 9.3; 95%CI: 3.5-24.8) and at re-evaluation age under 3 months (aOR: 12.8; 95%CI: 5.5-29.9) and an unconfirmed infection in the final urine culture (aOR: 30.8; 14.7-64.3). CONCLUSION: Adherence to the protocol was good but could be increased by a better re-evaluation procedure with the result of the urine culture. ESBL Enterobacteriaceae-related UTIs were still rare enough to influence the efficacy of management.

[Evaluation of ambulatory prescribing for community-acquired pneumonia in children]. / Évaluation des prescriptions dans la prise en charge des pneumonies aiguës communautaires de l'enfant.

OBJECTIVE: To determine how national recommendations for the treatment of acute community-acquired pneumonia (CAP) are applied in children. METHODS: A phone survey was conducted in northern France. A standardized questionnaire was submitted to randomized general practitioners (GPs), private pediatricians, and pediatric fellows to analyze their practices for CAP in children. Diagnostic and treatment data were collected for the last child they had treated for CAP and for a factitious clinical case of CAP. Treatments, particularly prescribing antibiotics, were compared to the guidelines published in 2005 for lower respiratory tract infections, in order to determine the percentage of "good prescribers". RESULTS: A total of 101 physicians were involved: 77 senior physicians (62 GPs and 15 private pediatricians) and 24 pediatric fellows. For the last child treated for a CAP (mean age: 4.5 years±3.4), amoxicillin was prescribed in 29% of cases and associated (most of the time by GPs) with clavulanic acid in 54%. For the factitious clinical case (age: 3 years), amoxicillin alone was prescribed in 50% of cases and associated with clavulanic acid in 45%. Also considering recommended doses and length of treatment, the percentage of "good prescribers" for senior physicians for each situation was 15% and 16%, respectively, and for pediatric residents was 52% and 50%. CONCLUSION: Guidelines for CAP in children were insufficiently followed.

Survey of hospital procedures for parapneumonic effusion in children highlights need for standardised management.

AIM: This study sought to evaluate the initial management of children with parapneumonic effusion admitted to all French university hospitals. METHODS: A nationwide survey of all 35 university hospitals took place in 2011 to assess practices for children with parapneumonic effusion, using a hypothetical clinical vignette and a standardised questionnaire. Two to four paediatricians per hospital were interviewed and asked about their initial management, probabilistic antibiotic therapy and its adaptation to microbiological results and subsequent course. Answers from paediatricians working in emergency departments, intensive care units and conventional paediatric units were compared. RESULTS: Of the 100 paediatricians contacted, 95 responded. Of these, 98% would order an initial blood test, 70% would order diagnostic thoracentesis, and all would start immediate antibiotic therapy: 31% with a single drug, 67% with two drugs and 2% with three drugs. The most frequent initial choices were third-generation cephalosporin alone (17%) or combined with rifampicin (34%) or vancomycin (24%). Adaptation varied according to drug used, dose and duration, especially when the microorganism was not Streptococcus pneumoniae. Practices did not differ significantly among the different groups of paediatricians. CONCLUSION: Standardised management of parapneumonic effusion, including routine thoracentesis and more consistent prescription of antibiotics, is needed.

[Fluoroquinolones to prevent bacterial infection in children with chemotherapy induced neutropenia: is it reasonable?]. / Prophylaxie par les fluoroquinolones dans la neutropénie post-chimiothérapie de l'enfant : est-ce bien raisonnable ?

Chemotherapy-induced febrile neutropenia is a frequent event in children with cancer, with a high morbidity. Antibiotic prophylaxis has been proposed for many years to prevent infectious diseases in patients with neutropenia. Fluoroquinolone prophylaxis induced a significant reduction of mortality and infectious morbidities in these situations. Less data are available in children with neutropenia. The emergence of antimicrobial resistance involving not only quinolones, but also cephalosporins, aminoglycosides and penems, is the main long term risk. This article summarise the usefulness of the prophylactic antibiotic treatment and its perspective in children with cancer.

[Reasons for low usage of strep A rapid antigen detection tests for pharyngitis in private medical practice]. / Motifs de la mauvaise utilisation des tests de diagnostic rapide du streptocoque de groupe A en médecine libérale.

UNLABELLED: Rapid group A Streptococcus (GAS) antigen detection tests (RDT) have high diagnostic performance for the management of acute pharyngitis and are recommended before any antibiotic (ATB) prescription in France to reduce ATB use. The rate of general practitioners (GPs) using GAS RDT is low and decreasing. Our aims were to describe the reasons for pediatricians and GPs not using RDT or for prescribing ATB despite of a negative RDT. METHODS: In 2011, a survey was conducted in a random sample of 368 GPs plus all ambulatory pediatricians (n=82) in the Nord-Pas-de-Calais region of France. RESULTS: Response rates were 74% (n=61) for pediatricians and 18% (n=68) for GPs. RDTs for pharyngitis were used by 75% [95% CI: 63-85] of pediatricians and 53% [95% CI: 41-64] of GPs (P<0.001). RDTs were systematically used in children 3years of age and older by only 59% of all physicians using RDTs. An ATB was systematically prescribed in case of positive RDT by 96% of physicians and eventually prescribed in case of negative RDT by 74%. The main reasons for ATB prescription in case of negative RDT were association with otitis media (51%), second visit for the same pharyngitis (45%), and high clinical suspicion of GAS pharyngitis (36%). Forty percent of non-RDT users had used them in the past. The 3 main reasons for not using RDT were the lack of time (57%), high confidence in clinical data to discriminate GAS pharyngitis (48%), and low confidence in RDT (27%). DISCUSSION: This survey highlights the lack of knowledge about low and high discriminant values of clinical data and RDT, respectively, especially the excellent negative predictive value of RDTs, and an erroneous assessment of the low risk of missing GAS pharyngitis compared to the consequences of inappropriate ATB use.

[Recurrent and metastatic infantile fibrosarcoma: a case report]. / Fibrosarcome infantile récidivant et métastatique: à propos d'un cas.

Infantile fibrosarcoma is a rare malignant tumor that usually occurs during the 1st year of life. It accounts for approximately 5-10% of all sarcomas in infants younger than 1 year of age. It usually has indolent progression and metastatic spread is rare. We report the case of a patient who had infantile fibrosarcoma of the trunk. At birth, the baby presented a soft tissue mass of the scapulothoracic region. Histopathological examination after complete surgical resection at first suggested an angioma. Reanalysis of the histology after a metastatic relapse resulted in the diagnosis of infantile fibrosarcoma, which was confirmed by the presence of the specific translocation seen in infantile fibrosarcoma (ETV6/NTRK3). This patient's progression was uncommon because he developed 3 metastatic relapses. The treatment consisted of surgery, chemotherapy, and radiation therapy. The patient is alive with persistent complete remission. We discuss the diagnostic and therapeutic issues of infantile fibrosarcoma. There is a risk of erroneous diagnosis in newborn infants between benign angiomatous tumor and infantile fibrosarcoma. The fusion transcript ETV6-NTRK3 resulting from the specific chromosomal translocation t(12;15)(p13;q25) is now a useful diagnostic tool for infantile fibrosarcoma. Surgery with wide resection is the mainstay of treatment. However, infantile fibrosarcoma is a chemosensitive tumor. If initial surgery cannot be done without mutilation or is impossible, preoperative chemotherapy should be given. The role of radiation therapy is still debated.