Characteristics of Patients with Persistent COVID-19 Symptoms and Unscheduled Return Visits to a Centre for COVID-19 Evaluation.

This retrospective study aimed to evaluate the characteristics of patients with long COVID syndrome. This study included 457 adults who had at least one persistent symptom after COVID-19 infection. The median time interval between the last SARS-CoV-2 infection and emergency room presentation was 3 months.

Promoting Regeneration in Degenerative Disc Disease.

Objective: The degenerative disc disease has a multifactorial etiology and mechanical stress is one of the most important etiological factor. The purpose of this study was to evaluate the intervertebral disc (IVD) after axial stress diminution from the point of view of its proteoglycan (PG) content, with preoteoglicans (PGs) being very important in the normal function but also in the degenerative or regenerative processes.

Methods: This is a single-center, prospective, non-randomized study of 38 degenerated intervertebral discs treated with monosegmental or polisegmental posterior lumbar spinal fixation in 27 patients.

Performance and modelling of retention in microemulsion liquid chromatography.

The capability of liquid chromatography with microemulsions (MEs) as mobile phases was studied for the analysis of four parabens (butylparaben, ethylparaben, methylparaben, and propylparaben) and seven β-adrenoceptor antagonists (acebutolol, atenolol, carteolol, metoprolol, oxprenolol, propranolol, and timolol). MEs were formed by mixing aqueous solutions of the anionic surfactant sodium dodecyl sulphate, the alcohol 1-butanol that played the role of co-surfactant, and octane as oil. In order to guarantee the formation of stable MEs, a preliminary study was carried out to determine the appropriate ranges of concentrations of the three components.