Frequency analysis of sound by the cochlea is the most fundamental property of the auditory system. Despite its importance, the resolution of this frequency analysis in humans remains controversial. ...The controversy persists because the methods used to estimate tuning in humans are indirect and have not all been independently validated in other species. Some data suggest that human cochlear tuning is considerably sharper than that of laboratory animals, while others suggest little or no difference between species. We show here in a single species (ferret) that behavioral estimates of tuning bandwidths obtained using perceptual masking methods, and objective estimates obtained using otoacoustic emissions, both also employed in humans, agree closely with direct physiological measurements from single auditory-nerve fibers. Combined with human behavioral data, this outcome indicates that the frequency analysis performed by the human cochlea is of significantly higher resolution than found in common laboratory animals. This finding raises important questions about the evolutionary origins of human cochlear tuning, its role in the emergence of speech communication, and the mechanisms underlying our ability to separate and process natural sounds in complex acoustic environments.
Frequency selectivity is a fundamental property of hearing which affects almost all aspects of auditory processing. Here auditory filter widths at 1, 3, 7, and 10 kHz were estimated from behavioural ...thresholds using the notched-noise method Patterson, Nimmo-Smith, Weber, and Milroy, J. Acoust. Soc. Am. 72, 1788-1803 (1982) in ferrets. The mean bandwidth was 21% of the signal frequency, excluding wider bandwidths at 1 kHz (65%). They were comparable although on average broader than equivalent measurements in other mammals (∼11%-20%), and wider than bandwidths measured from the auditory nerve in ferrets (∼18%). In non-human mammals there is considerable variation between individuals, species, and in the correspondence with auditory nerve tuning.
Guidelines advocate minimally invasive drainage rather than open surgery for infected pancreatic necrosis (IPN) after acute pancreatitis. We hypothesized that the conservative approach could be ...extended even further by treating patients using an antibiotics-only protocol.
Between June 2009 and July 2017, patients with IPN were selectively managed with carbapenem antibiotics for a minimum of 6 weeks. We compared these patients with patients who underwent minimal access retroperitoneal pancreatic necrosectomy (MARPN) for IPN to identify characteristics of this patient group.
Of 33 patients with radiologically proven IPN, 13 patients received antibiotics without any surgical or radiological intervention and resulted in no disease-specific mortality and one case of pancreatic insufficiency. In comparison, 44 patients underwent MARPN with a mortality of 20%, and 81.8% developed pancreatic insufficiency. The modified Glasgow score and computed tomography severity score was less in the antibiotic-only group (P<0.001 and P=0.014, respectively). Patients who underwent MARPN had lower serum haemoglobin and albumin levels (P=0.030 and 0.001, respectively), and a higher C-reactive protein (P=0.027).
Conservative treatment of IPN with antibiotics is a valid management option for haemodynamically stable patients experiencing less severe disease, requiring careful selection by experienced clinicians.
Background: The use of mobile technologies for data capture and transmission has the potential to streamline clinical trials, but researchers lack methods for collecting, processing, and interpreting ...data from these tools. Objectives: To assess the performance of a technical platform for collecting and transmitting data from six mobile technologies in the clinic and at home, to apply methods for comparing them to clinical standard devices, and to measure their usability, including how willing subjects were to use them on a regular basis. Methods: In part 1 of the study, conducted over 3 weeks in the clinic, we tested two device pairs (mobile vs. clinical standard blood pressure monitor and mobile vs. clinical standard spirometer) on 25 healthy volunteers. In part 2 of the study, conducted over 3 days both in the clinic and at home, we tested the same two device pairs as in part 1, plus four additional pairs (mobile vs. clinical standard pulse oximeter, glucose meter, weight scale, and activity monitor), on 22 healthy volunteers. Results: Data collection reliability was 98.1% in part 1 of the study and 95.8% in part 2 (the percentages exclude the wearable activity monitor, which collects data continuously). In part 1, 20 of 1,049 overall expected measurements were missing (1.9%), and in part 2, 45 of 1,083 were missing (4.2%). The most common reason for missing data was a single malfunctioning spirometer (13 of 20 total missed readings) in part 1, and that the subject did not take the measurement (22 of 45 total missed readings) in part 2. Also in part 2, a higher proportion of at-home measurements than in-clinic readings were missing (12.6 vs. 2.7%). The data from this experimental study were unable to establish repeatability or agreement for every mobile technology; only the pulse oximeter demonstrated repeatability, and only the weight scale demonstrated agreement with the clinical standard device. Most mobile technologies received high “willingness to use” ratings from the patients on the questionnaires. Conclusions: This study demonstrated that the wireless data transmission and processing platform was dependable. It also identified three critical areas of study for advancing the use of mobile technologies in clinical research: (1) if a mobile technology captures more than one type of endpoint (such as blood pressure and pulse), repeatability and agreement may need to be established for each endpoint to be included in a clinical trial; (2) researchers need to develop criteria for excluding invalid device readings (to be identified by algorithms in real time) for the population studied using ranges based on accumulated subject data and established norms; and (3) careful examination of a mobile technology’s performance (reliability, repeatability, and agreement with accepted reference devices) during pilot testing is essential, even for medical devices approved by regulators.
Acute exacerbation of idiopathic pulmonary fibrosis has been defined as an acute, clinically significant, respiratory deterioration of unidentifiable cause. The objective of this international ...working group report on acute exacerbation of idiopathic pulmonary fibrosis was to provide a comprehensive update on the topic. A literature review was conducted to identify all relevant English text publications and abstracts. Evidence-based updates on the epidemiology, etiology, risk factors, prognosis, and management of acute exacerbations of idiopathic pulmonary fibrosis are provided. Finally, to better reflect the current state of knowledge and improve the feasibility of future research into its etiology and treatment, the working group proposes a new conceptual framework for acute respiratory deterioration in idiopathic pulmonary fibrosis and a revised definition and diagnostic criteria for acute exacerbation of idiopathic pulmonary fibrosis.
The aim of this study was to compare radiology-based prediction models in rheumatoid arthritis-related interstitial lung disease (RAILD) to identify patients with a progressive fibrosis ...phenotype.RAILD patients had computed tomography (CT) scans scored visually and using CALIPER and forced vital capacity (FVC) measurements. Outcomes were evaluated using three techniques, as follows. 1) Scleroderma system evaluating visual interstitial lung disease extent and FVC values; 2) Fleischner Society idiopathic pulmonary fibrosis (IPF) diagnostic guidelines applied to RAILD; and 3) CALIPER scores of vessel-related structures (VRS). Outcomes were compared to IPF patients.On univariable Cox analysis, all three staging systems strongly predicted outcome (scleroderma system hazard ratio (HR) 3.78, p=9×10
; Fleischner system HR 1.98, p=2×10
; and 4.4% VRS threshold HR 3.10, p=4×10
). When the scleroderma and Fleischner systems were combined, termed the progressive fibrotic system (C-statistic 0.71), they identified a patient subset (n=36) with a progressive fibrotic phenotype and similar 4-year survival to IPF. On multivariable analysis, with adjustment for patient age, sex and smoking status, when analysed alongside the progressive fibrotic system, the VRS threshold of 4.4% independently predicted outcome (model C-statistic 0.77).The combination of two visual CT-based staging systems identified 23% of an RAILD cohort with an IPF-like progressive fibrotic phenotype. The addition of a computer-derived VRS threshold further improved outcome prediction and model fit, beyond that encompassed by RAILD measures of disease severity and extent.
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