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Introduction: Pneumomediastinum is an uncommon condition in pediatrics with a peak incidence in adolescence. The most common symptom of spontaneous pneumomediastinum (SPM) is chest pain; however, most patients are asymptomatic. Hamman's sign is a rare but pathognomonic sign of pneumomediastinum. This clinical sign is characterized by a crunching, rasping sound, synchronous with the heartbeat, heard over the precordium. Hamman's syndrome is a SPM associated with subcutaneous emphysema., Case Description: We report the case of a previously healthy 15-year-old adolescent male, an elite athlete, who was admitted to hospital with a 3-day history of chest pain. There was no history of previous respiratory infections, invasive procedures, or trauma. On physical examination, he had a palpable subcutaneous neck edema and a crackle on cardiac auscultation. Chest and neck radiographs confirmed ectopic air in the mediastinum and subcutaneous neck emphysema. Given the identification of Hamman's sign and the presence of emphysema, the diagnosis of Hamman's syndrome was made and symptomatic treatment was given with complete resolution., Conclusion: This case highlights the value of physical examination and medical semiology in the diagnosis of Hamman's syndrome, especially in the presence of the pathognomonic Hamman's sign., (© 2025 Wiley Periodicals LLC.)

We report the electrochemical detection of estriol using carbon black nanoballs (CNB) decorated with silver nanoparticles (AgNP) as electrode material. Homogeneous, porous films on glassy carbon electrodes (GCE) were obtained, with diameters of 20 - 25nm for CNB and 5 - 6nm for AgNP. CNB/AgNP electrodes had increased conductivity and electroactive area in comparison with bare GCE and GCE/CNB, according to cyclic voltammetry and electrochemical impedance spectroscopy. The oxidation potential peak was also down shifted by 93mV, compared to the bare GC electrode. Differential pulse voltammetry data were obtained in 0.1molL -1 PBS (pH 7.0) to detect estriol without the purification step, in the linear range between 0.2 and 3.0µmolL -1 with detection and quantification limits of 0.16 and 0.5µmolL -1 (0.04 and 0.16mgL -1 ), respectively. The sensor was used to detect estriol in a creek water sample with the same performance as in the official methodology based on high performance liquid chromatography., (Copyright © 2017 Elsevier B.V. All rights reserved.)

We report on the synthesis, characterization and applications of a Printex L6 carbon-silver hybrid nanomaterial (PC-Ag), which was obtained using a polyol method. In addition, we also highlight the use of Printex L6 nano-carbon as a much cheaper alternative to the use of carbon nanotubes and graphene. The silver nanoparticles (AgNP) were prepared directly on the surface of the Printex 6L carbon "nanocarbon" material using ethylene glycol as the reducing agent. The hybrid nanomaterial was characterized by High-angle annular dark-field transmission electron microscopy (HAADF-TEM), energy-dispersive X-ray spectroscopy (EDX), selected area electron diffraction (SAED), Raman spectroscopy and cyclic voltammetry. Optimized electrocatalytic activity on glassy carbon electrode was reached for the architecture GC/PC-Ag, the silver nanoparticles with size ranging between 1 and 2 nm were well-distributed throughout the hybrid material. The synergy between PC nano-carbons and AgNPs was verified by detection of gallic acid (GA) at a low applied potential (0.091 V vs. Ag/AgCl). GA detection was performed in a concentration range between 5.0 × 10(-7) and 8.5 × 10(-6) mol L(-1), with a detection limit of 6.63 × 10(-8) mol L(-1) (66.3 nmol L(-1)), which is considerably lower than similar devices. The approach for fabricating the reproducible GC/PC-Ag electrodes is entirely generic and may be explored for other types of (bio)sensors and devices., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Initial investigations indicated the use of the Marmoset Predator Confrontation Test (MPCT) as an experimental procedure to measure fear/anxiety-related behaviors in non-human primates. However, possible long-term habituation effects and re-use of experimental subjects need to be verified. This study, therefore, compared the behavioral response of experienced versus naïve adult black tufted-ear marmosets (Callithrix penicillata) in the MPCT, with/without diazepam administrations. Subjects were tested in the figure-8 maze and confronted with a taxidermized wild-cat predator stimulus. After four initial 20-min maze habituation sessions, each subject was submitted to two randomly-assigned 20-min predator confrontation sessions: vehicle and 2 mg/kg of diazepam. Confrontation with the predator induced significant behavioral changes; i.e., proximic avoidance and tsik-tsik alarm call. Diazepam administration, concomitant to predator exposure, reversed the behavioral changes observed. In both the experienced and naïve marmosets a similar behavioral profile and response pattern to diazepam was detected, corroborating the important selective pressure that felines seem to have on marmoset behavioral ecology. Therefore, during a more naturalistic-like regimen--i.e., recurring intermittent predator encounters--the general response pattern remains highly consistent, regardless of prior experience. One may consider the re-use of marmoset subjects in the MPCT, particularly under these specific conditions (i.e. repeated 20-min confrontations, 72-h apart).