Kinetics of inflammatory biomarkers to predict one-year mortality in older patients hospitalized for pneumonia: a multivariable analysis.

OBJECTIVES: Long-term mortality is increased in older patients with pneumonia. We aimed to test whether residual inflammation is predictive of one-year mortality after pneumonia. METHODS: Inflammation biomarkers (C-reactive protein [CRP], interleukin [IL]-6 and IL-8, tumor necrosis factor-α, serum amyloid A, neopterin, myeloperoxidase, anti-apolipoprotein A-1, and anti-phosphorylcholine IgM) were measured at admission and discharge in older patients hospitalized for pneumonia in a prospective study. Univariate and multivariate analyses were conducted using absolute level at discharge and relative and absolute differences between admission and discharge for all biomarkers, along with usual prognostic factors. RESULTS: In the 133 included patients (median age, 83 years [interquartile range: 78-89]), one-year mortality was 26%. In univariate analysis, the relative difference of CRP levels had the highest area under the receiver operating characteristic curve (0.70; 95% confidence interval [CI] 0.60-0.80). A decrease of CRP levels of more than 67% between admission and discharge had 68% sensitivity and 68% specificity to predict survival. In multivariate analysis, lower body mass index (hazard ratio=0.87 [CI 95% 0.79-0.96], P-value=0.01), higher IL-8 (hazard ratio=1.02 [CI 95% 1.00-1.04], P-value=0.02), and higher CRP (1.01 [95% CI 1.00-1.02], P=0.01) at discharge were independently associated with mortality. CONCLUSION: Higher IL-8 and CRP levels at discharge were independently associated with one-year mortality. The relative CRP difference during hospitalization was the best individual biomarker for predicting one-year mortality.

Design and Simulation Investigation of Si3N4 Photonics Circuits for Wideband On-Chip Optical Gas Sensing around 2 µm Optical Wavelength.

We theoretically explore the potential of Si3N4 on SiO2 waveguide platform toward a wideband spectroscopic detection around the optical wavelength of 2 µm. The design of Si3N4 on SiO2 waveguide architectures consisting of a Si3N4 slot waveguide for a wideband on-chip spectroscopic sensing around 2 µm, and a Si3N4 multi-mode interferometer (MMI)-based coupler for light coupling from classical strip waveguide into the identified Si3N4 slot waveguides over a wide spectral range are investigated. We found that a Si3N4 on SiO2 slot waveguide structure can be designed for using as optical interaction part over a spectral range of interest, and the MMI structure can be used to enable broadband optical coupling from a strip to the slot waveguide for wideband multi-gas on-chip spectroscopic sensing. Reasons for the operating spectral range of the system are discussed.

Pneumonia prevention in the elderly patients: the other sides.

Pneumonia is one of the leading causes of morbidity and mortality from infection in elderly patients. The increased frequency of pneumonia among elderly subjects can be explained by the physiological changes linked to the progressive aging of the respiratory tree and the diminished immunological response. A spiral of event leads to frailty, infection and possible death; preventing pneumonia consists of controlling the risk factors. Dysphagia, which is associated with malnutrition and dehydration, is recognized as one of the major pathophysiological mechanism leading to pneumonia and its screening is crucial for the pneumonia risk assessment. The impairment in the oropharyngeal reflexes results in stagnation of foreign material in the lateral cavities of the pharynx which may then get aspirated repeatedly in the lungs and cause pneumonia. Pneumonia prevention starts with lifestyle modifications such as alcohol and tobacco cessation. A careful review of the risk-benefit of the prescribed medication is critical and adaptation may be required in elders with multiple morbidities. Respiratory physiotherapy and mobilization improve the functional status and hence may help reduce the risk of pneumonia. Maintaining teeth and masticatory efficiency is important if malnutrition and its consequences are to be avoided. Daily oral hygiene and regular professional removal of oral biofilm can prevent the onset of periodontitis and can avoid an oral environment favoring the colonization of respiratory pathogens than can then be aspirated into the lungs.

Accuracy of C-reactive protein, procalcitonin, serum amyloid A and neopterin for low-dose CT-scan confirmed pneumonia in elderly patients: A prospective cohort study.

OBJECTIVE: The diagnosis of pneumonia based on semiology and chest X-rays is frequently inaccurate, particularly in elderly patients. Older (C-reactive protein (CRP); procalcitonin (PCT)) or newer (Serum amyloid A (SAA); neopterin (NP)) biomarkers may increase the accuracy of pneumonia diagnosis, but data are scarce and conflicting. We assessed the accuracy of CRP, PCT, SAA, NP and the ratios CRP/NP and SAA/NP in a prospective observational cohort of elderly patients with suspected pneumonia. METHODS: We included consecutive patients more than 65 years old, with at least one respiratory symptom and one symptom or laboratory finding suggestive of infection, and a working diagnosis of pneumonia. Low-dose CT scan and comprehensive microbiological testing were done in all patients. The index tests, CRP, PCT, SAA and NP, were obtained within 24 hours. The reference diagnosis was assessed a posteriori by a panel of experts considering all available data, including patients' outcome. We used area under the curve (AUROC) and Youden index to assess the accuracy and obtain optimal cut-off of the index tests. RESULTS: 200 patients (median age 84 years) were included; 133 (67%) had pneumonia. AUROCs for the diagnosis of pneumonia was 0.64 (95% CI: 0.56-0.72) for CRP; 0.59 (95% CI: 0.51-0.68) for PCT; 0.60 (95% CI: 0.52-0.69) for SAA; 0.41 (95% CI: 0.32-0.49) for NP; 0.63 (95% CI: 0.55-0.71) for CRP/NP; and 0.61 (95% CI: 0.53-0.70) for SAA/NP. No cut-off resulted in satisfactory sensitivity or specificity. CONCLUSIONS: Accuracy of traditional (CRP, PCT) and newly proposed biomarkers (SAA, NP) and ratios of CRP/NP and SAA/NP was too low to help diagnosing pneumonia in the elderly. CRP had the highest AUROC. CLINICAL TRIAL REGISTRATION: NCT02467092.

Effect of 5-Day Nitrofurantoin vs Single-Dose Fosfomycin on Clinical Resolution of Uncomplicated Lower Urinary Tract Infection in Women: A Randomized Clinical Trial.

Importance: The use of nitrofurantoin and fosfomycin has increased since guidelines began recommending them as first-line therapy for lower urinary tract infection (UTI). Objective: To compare the clinical and microbiologic efficacy of nitrofurantoin and fosfomycin in women with uncomplicated cystitis. Design, Setting, and Participants: Multinational, open-label, analyst-blinded, randomized clinical trial including 513 nonpregnant women aged 18 years and older with symptoms of lower UTI (dysuria, urgency, frequency, or suprapubic tenderness), a positive urine dipstick result (with detection of nitrites or leukocyte esterase), and no known colonization or previous infection with uropathogens resistant to the study antibiotics. Recruitment took place from October 2013 through April 2017 at hospital units and outpatient clinics in Geneva, Switzerland; Lodz, Poland; and Petah-Tiqva, Israel. Interventions: Participants were randomized in a 1:1 ratio to oral nitrofurantoin, 100 mg 3 times a day for 5 days (n = 255), or a single 3-g dose of oral fosfomycin (n = 258). They returned 14 and 28 days after therapy completion for clinical evaluation and urine culture collection. Main Outcomes and Measures: The primary outcome was clinical response in the 28 days following therapy completion, defined as clinical resolution (complete resolution of symptoms and signs of UTI without prior failure), failure (need for additional or change in antibiotic treatment due to UTI or discontinuation due to lack of efficacy), or indeterminate (persistence of symptoms without objective evidence of infection). Secondary outcomes included bacteriologic response and incidence of adverse events. Results: Among 513 patients who were randomized (median age, 44 years [interquartile range, 31-64]), 475 (93%) completed the trial and 377 (73%) had a confirmed positive baseline culture. Clinical resolution through day 28 was achieved in 171 of 244 patients (70%) receiving nitrofurantoin vs 139 of 241 patients (58%) receiving fosfomycin (difference, 12% [95% CI, 4%-21%]; P = .004). Microbiologic resolution occurred in 129 of 175 (74%) vs 103 of 163 (63%), respectively (difference, 11% [95% CI, 1%-20%]; P = .04). Adverse events were few and primarily gastrointestinal; the most common were nausea and diarrhea (7/248 [3%] and 3/248 [1%] in the nitrofurantoin group vs 5/247 [2%] and 5/247 [1%] in the fosfomycin group, respectively). Conclusions and Relevance: Among women with uncomplicated UTI, 5-day nitrofurantoin, compared with single-dose fosfomycin, resulted in a significantly greater likelihood of clinical and microbiologic resolution at 28 days after therapy completion. Trial Registration: ClinicalTrials.gov Identifier: NCT01966653.

Management of Microbial Communities through Transient Disturbances Enhances the Functional Resilience of Nitrifying Gas-Biofilters to Future Disturbances.

Microbial communities have a key role for the performance of engineered ecosystems such as waste gas biofilters. Maintaining constant performance despite fluctuating environmental conditions is of prime interest, but it is highly challenging because the mechanisms that drive the response of microbial communities to disturbances still have to be disentangled. Here we demonstrate that the bioprocess performance and stability can be improved and reinforced in the face of disturbances, through a rationally predefined strategy of microbial resource management (MRM). This strategy was experimentally validated in replicated pilot-scale nitrifying gas-biofilters, for the two steps of nitrification. The associated biological mechanisms were unraveled through analysis of functions, abundances and community compositions for the major actors of nitrification in these biofilters, that is, ammonia-oxidizing bacteria (AOB) and Nitrobacter-like nitrite-oxidizers (NOB). Our MRM strategy, based on the application of successive, transient perturbations of increasing intensity, enabled to steer the nitrifier community in a favorable way through the selection of more resistant AOB and NOB sharing functional gene sequences close to those of, respectively, Nitrosomonas eutropha and Nitrobacter hamburgensis that are well adapted to high N load. The induced community shifts resulted in significant enhancement of nitrification resilience capacity following the intense perturbation.

[Choice of career by French medical students after the national ranking exam in 2012]. / Analyse du choix des 7658 étudiants en médecine après les épreuves classantes nationales 2012.

PURPOSE: Since 2011, the French medical students ranked after a national ranking exam (NRE) are making their career choice among 11 disciplines detailing the chosen one. Before 2011, this precise choice was unknown. Our work is the first descriptive study of French medical students choice of career after the NRE, precising the medical specialty chosen and the city of practical formation. METHODS: We analyzed the Excel(®) file transmitted by the 'Agence régionale de santé d'Aquitaine' once students choice done after the 2012 NRE. A median range analysis was made for disciplines and city formation choices. For medical and surgery specialties, the analysis was compared to regional medical densities. RESULTS: According to the median national choice, the first sixth disciplines chosen are ophthalmology, nephrology, internal medicine, radiology, cardiology and dermatology. Women are more attracted by medical gynecology, obstetrics, pediatrics, or dermatology; men mostly by neurosurgery, general surgery, nuclear medicine or cardiology. The most rated cities of formation according to their national median range of choice are Lyon, Montpellier and Paris. A majority of students (59 %) moved to another city to obtain the desired specialty. Among general practitioners, 56 % of students stayed in the city where they had been trained. PERSPECTIVES: Our study may provide concrete objectives for French medical students accomplishing their second cycle of medical studies, as well as supplemental data for French medical demographic management.

Resistance and resilience of removal efficiency and bacterial community structure of gas biofilters exposed to repeated shock loads.

Since full-scale biofilters are often operated under fluctuating conditions, it is critical to understand their response to transient states. Four pilot-scale biofilters treating a composting gas mixture and undergoing repeated substrate pulses of increasing intensity were studied. A systematic approach was proposed to quantify the resistance and resilience capacity of their removal efficiency, which enabled to distinguish between recalcitrant (ammonia, DMDS, ketones) and easily degradable (esters and aldehyde) compounds. The threshold of disturbing shock intensity and the influence of disturbance history depended on the contaminant considered. The spatial and temporal distribution of the bacterial community structure in response to the perturbation regime was analysed by Denaturing Gradient Gel Electrophoresis (DGGE). Even if the substrate-pulses acted as a driving force for some community characteristics (community stratification), the structure-function relationships were trickier to evidence: the distributions of resistance and composition were only partially coupled, with contradictory results depending on the contaminant considered.

Global change could amplify fire effects on soil greenhouse gas emissions.

BACKGROUND: Little is known about the combined impacts of global environmental changes and ecological disturbances on ecosystem functioning, even though such combined impacts might play critical roles in shaping ecosystem processes that can in turn feed back to climate change, such as soil emissions of greenhouse gases. METHODOLOGY/PRINCIPAL FINDINGS: We took advantage of an accidental, low-severity wildfire that burned part of a long-term global change experiment to investigate the interactive effects of a fire disturbance and increases in CO(2) concentration, precipitation and nitrogen supply on soil nitrous oxide (N(2)O) emissions in a grassland ecosystem. We examined the responses of soil N(2)O emissions, as well as the responses of the two main microbial processes contributing to soil N(2)O production--nitrification and denitrification--and of their main drivers. We show that the fire disturbance greatly increased soil N(2)O emissions over a three-year period, and that elevated CO(2) and enhanced nitrogen supply amplified fire effects on soil N(2)O emissions: emissions increased by a factor of two with fire alone and by a factor of six under the combined influence of fire, elevated CO(2) and nitrogen. We also provide evidence that this response was caused by increased microbial denitrification, resulting from increased soil moisture and soil carbon and nitrogen availability in the burned and fertilized plots. CONCLUSIONS/SIGNIFICANCE: Our results indicate that the combined effects of fire and global environmental changes can exceed their effects in isolation, thereby creating unexpected feedbacks to soil greenhouse gas emissions. These findings highlight the need to further explore the impacts of ecological disturbances on ecosystem functioning in the context of global change if we wish to be able to model future soil greenhouse gas emissions with greater confidence.

Nickel mine spoils revegetation attempts: effect of pioneer plants on two functional bacterial communities involved in the N-cycle.

Nickel mine spoils in New Caledonia represent an extreme environment, rich in nickel and strongly deficient in elementary elements such as carbon and nitrogen. To rehabilitate these sites, revegetation attempts are performed with endemic plant species establishing dinitrogen-fixation symbiosis (Gymnostoma webbianum and Serianthes calycina). As this biological fixation process provides the major source of available nitrogen in this extreme environment, it could be expected that nitrogen cycling would be stimulated. To study the revegetation effect on mine spoils, the effect of the two pioneer plants on the structure and activity of two functional bacterial communities involved in the N-cycle was investigated. nifH and narG genes were used as molecular markers for dinitrogen-fixers and dissimilatory nitrate reducers respectively. In order to assess the influence of the plants on both communities, nine clone libraries were constructed for each targeted gene. Libraries containing 602 and 513 nifH and narG clones, respectively, were screened by restriction fragment length polymorphism (RFLP) analysis. One hundred and forty-one and 78 representative clones from at least all RFLP families containing more than one clone were sequenced from nifH and narG clone libraries respectively. Both pioneer plants modified the diversity and activity of the two functional communities. However, distinct effects were observed depending on the plant species and the community considered. Serianthes calycina strongly selected a diazotroph phylotype and restored the potential activity of both communities. In contrast, G. webbianum selected no particular phylotype and only restored a fixing activity.