In annular combustion chambers of aero-engines and gas turbines, acoustic coupling may arise from azimuthal modes which are less well damped than axial modes. Also, since the circumference is the ...largest length in the combustor, the azimuthal modes have the lowest resonance frequencies and are most prone to instability. Such a coupling raises many scientific issues which are considered in a small number of fundamental experiments. The present investigation focuses on this problem and provides experimental data on a special type of combustion instability in which the thermo-acoustic resonant coupling involves a combination of modes. This produces an unusual pattern of flame responses in which the distribution of heat release rate is slanted. Data are provided in the form of free radical light intensity patterns (interpreted as heat release rate distributions) and microphone signals detected in the plenum and chamber. It is shown that the slanted pattern is the signature of a combination of two modes with coinciding frequencies, the first being a standing azimuthal mode while the second is an axial mode. Measurements of the flame describing function on a single matrix burner at the fundamental frequency are used to explain the observed phase shift and amplitude in the flame responses of the different injectors in the annular combustor.
We describe the most widely used temporary hospital in Europe during the first pandemic wave, its structure, function, and achievements. Other models of care developed during the pandemic around the ...world were reviewed including their capacity, total bed/ICU bed ratio and time of use. We particularly analyzed the common and differential characteristics of this type of facilities. IFEMA Exhibition Center was transformed into a temporary 1,300-bed hospital, which was in continuous operation for 42 days. A total of 3,817 people were treated, generally patients with mild to moderate COVID-19, 91% of whom had pneumonia. The average length of stay was 5 to 36 days. The most frequent comorbidities were hypertension (16.5%), diabetes mellitus (9.1%), COPD (6%), asthma (4.6%), obesity (2.9%) and dementia (1.6%). A total of 113 patients (3%) were transferred to another centers for aggravation, 19 (0.5%) were admitted to ICU and 16 patients (0.4%) died. An element of great help to reducing the overload of care in large hospitals during peaks of health emergencies could be these flexible structures capable of absorbing the excess of patients. These must be safe, breaking domestic transmission and guarantee social and emotional needs of patients. The success of these structures depends on delimitation in admission criteria taking into account the proportion of patients who may require, during admission, assistance in the critical care area.
In most countries the coverage of seasonal influenza vaccination in pregnant women is low. We investigated the acceptance, reasons for rejection and professional involvement related to vaccine ...information in pregnant women in Valencia, Spain.
Observational retrospective study in 200 pregnant women, 100 vaccinated and 100 unvaccinated, were interviewed during the 2014/2015 vaccination campaign. Electronic medical records, immunization registry and telephone interviews were used to determine reasons for vaccination and immunization rejection.
40.5% of pregnant women in the health department were vaccinated. The midwife was identified as source of information for 89% of women. The vaccine was rejected due to low perceptions of risk of influenza infection (23%), lack of information (19%), considering the vaccine as superfluous (16%), close proximity of delivery date (13%) and fear of side effects (12%).
Pregnant women in Spain declined to be vaccinated due to under-estimation of the risk of contracting or being harmed by influenza, and lack of information. Interventions aiming to optimize vaccination coverage should include information addressing the safety and effectiveness of the current vaccine together with improved professional training and motivation.
The high transmissibility of SARS-CoV-2 before and shortly after the onset of symptoms suggests that only diagnosing and isolating symptomatic patients may not be sufficient to interrupt the spread ...of infection; therefore, public health measures such as personal distancing are also necessary. Additionally, it will be important to detect the newly infected individuals who remain asymptomatic, which may account for 50% or more of the cases. Molecular techniques are the "gold standard" for the diagnosis of SARS-CoV-2 infection. However, the massive use of these techniques has generated some problems. On the one hand, the scarcity of resources (analyzers, fungibles and reagents), and on the other the delay in the notification of results. These two facts translate into a lag in the application of isolation measures among cases and contacts, which favors the spread of the infection. Antigen detection tests are also direct diagnostic methods, with the advantage of obtaining the result in a few minutes and at the very "pointof-care". Furthermore, the simplicity and low cost of these tests allow them to be repeated on successive days in certain clinical settings. The sensitivity of antigen tests is generally lower than that of nucleic acid tests, although their specificity is comparable. Antigenic tests have been shown to be more valid in the days around the onset of symptoms, when the viral load in the nasopharynx is higher. Having a rapid and real-time viral detection assay such as the antigen test has been shown to be more useful to control the spread of the infection than more sensitive tests, but with greater cost and response time, such as in case of molecular tests. The main health institutions such as the WHO, the CDC and the Ministry of Health of the Government of Spain propose the use of antigenic tests in a wide variety of strategies to respond to the pandemic. This document aims to support physicians involved in the care of patients with suspected SC2 infection, in the context of a growing incidence in Spain since September 2020, which already represents the second pandemic wave of COVID-19.
Fosfomycin is a bactericidal antibiotic that interferes with cell wall synthesis. The drug therefore has a broad spectrum of activity against a wide range of Gram-positive and Gram-negative bacteria. ...Both the European Medicines Agency (EMA) and the US Food and Drug Administration (FDA) have started review processes of the accumulated information on the use of fosfomycin and on information from new clinical trials. The intent is to establish usage terms in Europe and to authorize the sale of fosfomycin in the US. This monograph reviews the most current aspects of the compound. From the microbiological point of view, fosfomycin's single mechanism of action can provide a synergistic effect to other classes of antibiotics, including β-lactams, aminoglycosides, lipopeptides and fluoroquinolones. The resistance mechanisms include the reduced intracellular transport of the antibiotic, the change in target and the direct inactivation of the antibiotic by metalloenzymes and kinases; however, the clinical impact of some of these mechanisms has not yet been elucidated. The lack of agreement in determining the sensitivity cutoffs between the Clinical and Laboratory Standards Institute (CLSI) (≤64 mg/L) and the European Committee on Antimicrobial Susceptibility Testing (EUCAST) (≤32 mg/L), the fact that a number of microorganisms require a higher MIC (Klebsiella spp., Enterobacter spp., Serratia spp., Pseudomonas aeruginosa) and the drug's different effective concentrations against Gram-positive and Gram-negative bacteria have resulted in recommended dosages for treating multiresistant microorganism infections that vary between 8 and 12 g/day for Gram-positive bacteria and 16 and 24 g/day for Gram-negative bacteria. Fosfomycin has 3 presentations (intravenous with disodium salt, oral with calcium salt and combined with tromethamine),has good distribution in tissues and abscesses and is well tolerated. The pharmacodynamic ratio of dosage production for fosfomycin is AUC/MIC. However, the pharmacokinetics/pharmacodynamic ratio could be optimized in daily practice based on the pathogen, the patient's clinical profile or the infection model. Fosfomycin is the treatment of choice for cystitis in immunocompetent patients, patients with transplants, pregnant women and in pediatric settings. The drug is especially useful due to its microbiological activity and oral posology in cystitis caused by ESBL bacteria. Administer intravenously at high doses and combined with other antimicrobial agents. Fosfomycin has been useful in treating infections by multiresistant Gram-negative bacteria, such as Enterobacteriaceae, carbapenemase carriers and P. aeruginosa, extensively resistant or panresistant in urinary infections and in skin and soft tissue. Fosfomycin has also been shown active in combination with daptomycin or imipenem in osteoarticular infections by methicillin-resistant Staphylococcus aureus. Fosfomycin is an old antibiotic that still has much to reveal.
Background:The overall occurrence of Herpes zoster (HZ) infections in patients with rheumatoid arthritis (RA) is greater than in the general population although is controversial whether the use of ...the different disease-modifying antirheumatic drugs (DMARDs) increases this risk.Objectives:To investigate the incidence and factors associate to HZ infections in patients with RA exposed to biologic agents (BA) and small molecule JAK inhibitors (JAKi), and to describe RA disease features at the moment of HZ infection.Methods:Retrospective longitudinal study was conducted. We included RA patients seen at the rheumatology outpatient clinic of tertiary hospital, commencing BA (anti-TNF therapy and no anti-TNF therapy) or JAKi from Jan 2007 until Dec 2017, and followed up until end of study (Dec 2019). The outcome of interest was the occurrence of HZ infection, the diagnosis of HZ events was based on the rheumatologist’s report. Covariables: sociodemographic, clinical, and concomitant treatments including glucocorticoids, conventional synthetic DMARDs (csDMARDs). Survival techniques were used to estimate the incidence of HZ (IR), per 1000 patient-year (PYs) with the respective Confidence Interval 95%CI. Cox multivariate regression model to compare the risk of HZ was performed. Results were expressed in Hazard ratio (HR).Results:474 RA patients were included, starting 881 different courses of treatment (1954.86 patients-years of follow-up). 382 (80.6%) were women with a mean (SD) age of 56.9 (15.0) years at first BA. Across all groups of treatments, a total 18 HZ were recorded, events were non-serious and involved 1 or 2 dermatomes. The mean age (SD) at moment of the infection was 62 (11) years and 10 cases were on prednisone > 7.5 mg/day. 13 HZ cases (72.2%) occurred on treatment with anti-TNF treatment (6 with adalimumab, 4 with certolizumab and 1 with infliximab), 4 (22.2%) cases were on treatment with rituximab one occurred during tocilizumab prescription. The overall incidence of HZ was 9.20 cases per 1000PYs 5.80-14.61. The crude IR was similar between gender, increased with age (Patients < 46 years: 2.17 0.3-15.4; >70 years 14.1 5.8-33.8), was higher with concomitant use of two csDMARDs (IR: 15.68 7.8-31.7, and was similar between anti-TNF and non anti-TNF therapy. None HZ event was recorded in patients exposed to JAKi. In the multivariate analysis, age (HR: 1.05, p: 0.006), prednisone dose > 7.5 mg/day (HR: 2.83, p: 0.02) and the concomitant use of two csDMARDs (HR: 2.34 p: 0.039) increase the risk for HZ. Lymphopenia (HR: 2.6; p=0.06) achieved a trend and BA therapy dropped from the model.Conclusion:HZ incidence rate was 9.20 cases per 1000PYs, HZ occurrence in RA patients cannot be attributed solely to the current BA or JAKi treatment and other factors involved must be taking in count as age, concomitant DMARDs prescriptions, and use of glucocorticoids. Our data suggest that preventive strategies for HZ should be developed for patients with RA.Disclosure of Interests:None declared
Background. From April through June 2008, we identified 12 patients in the intensive care unit and 3 patients on other wards infected with methicillin-resistant Staphylococcus aureus that was also ...resistant to linezolid. We investigated the mechanism of resistance —point mutations in domain V of 23S ribosomal RNA (rRNA) or presence of the cfr gene —involved in the outbreak. Methods. Strains for the study were obtained in the intensive care unit and other wards. Minimal inhibitory concentrations were determined using automated methods, the E-test, or dilution in Mueller-Hinton agar in accordance with Clinical and Laboratory Standards Institute guidelines. Strains were genotyped using pulsed-field gel electrophoresis and were sequenced to determine the presence of point mutations in 23S rRNA. The presence of the cfr gene was determined by specific polymerase chain reaction. Results. The minimal inhibitory concentrations of linezolid ranged from 16 mg/L to 32 mg/L, and all the strains were susceptible to tigecycline, vancomycin, and daptomycin. Typing of strains sequentially isolated by pulsed-field gel electrophoresis showed that each patient carried only 1 clonal type of linezolid-resistant, methicillin-resistant S. aureus as detected by sequential isolations. The presence of the cfr gene was confirmed in all the isolates. Furthermore, sequencing of domain V of 23S rRNA showed that the most common mechanism of linezolid resistance reported to date, mutation G2576T, was not detected in any of the strains analyzed. Conclusions. We report the presence of the cfr gene underlying the resistance mechanism involved in a clinical outbreak of linezolid-resistant S. aureus.
Delafloxacin (DLX) is a new fluoroquinolone pending approval, which has shown a good in vitro and in vivo activity against major pathogens associated with skin and soft tissue infections and ...community-acquired respiratory tract infections. DLX also shows good activity against a broad spectrum of microorganisms, including those resistant to other fluoroquinolones, as methicillin-resistant
. Its pharmacokinetic properties and excellent activity in acidic environments make DLX an alternative in the treatment of these and other infections. In this manuscript, a detailed analysis of this new fluoroquinolone is performed, from its chemical structure to its in vivo activity in recently published clinical trials. Its possible place in the current antimicrobial outlook and in other infectious models is also discussed.
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