One year of surgical mask testing at the University of Bologna labs: Lessons learned from data analysis

The outbreak of SARS-CoV-2 pandemic highlighted the worldwide lack of surgical masks and personal protective equipment, which represent the main defense available against respiratory diseases as COVID-19. At the time, masks shortage was dramatic in Italy, the first European country seriously hit by the pandemic: aiming to address the emergency and to support the Italian industrial reconversion to the production of surgical masks, a multidisciplinary team of the University of Bologna organized a laboratory to test surgical masks according to European regulations. The group, driven by the expertise of chemical engineers, microbiologists, and occupational physicians, set-up the test lines to perform all the functional tests required. The laboratory started its activity on late March 2020, and as of the end of December of the same year 435 surgical mask prototypes were tested, with only 42 masks compliant to the European standard. From the analysis of the materials used, as well as of the production methods, it was found that a compliant surgical mask is most likely composed of three layers, a central meltblown filtration layer and two external spunbond comfort layers. An increase in the material thickness (grammage), or in the number of layers, does not improve the filtration efficiency, but leads to poor breathability, indicating that filtration depends not only on pure size exclusion, but other mechanisms are taking place (driven by electrostatic charge). The study critically reviewed the European standard procedures, identifying the weak aspects; among the others, the control of aerosol droplet size during the bacterial filtration test results to be crucial, since it can change the classification of a mask when its performance lies near to the limiting values of 95 or 98%.

Diagnostic imaging of ankle impingement syndromes in athletes

The chronic ankle pain is a very frequent clinical problem, which is often characterized by a painful mechanical limitation of full-range ankle movement. A large amount of causes are involved in its pathogenesis, but the most common forms are secondary to an osseous or soft tissue abnormality. Especially for professional athletes, impingement lesions are the most important causes of chronic pain; however, this symptomatology can also affect ordinary people, mostly in those who work in environments that cause severe mechanical stress on the joints. This group of pathologies is characterized by a joint conflict secondary to an abnormal contact among bone surfaces or between bones and soft tissues. Diagnosis is mainly clinic and secondly supported by imaging in order to localize the critical area of impingement and determine the organic cause responsible for the joint conflict. Treatments for different forms of impingement are similar. Usually, the first step is a conservative approach (rest, physiotherapy, ankle bracing, shoe modification and local injection of corticosteroids), and only in case of unsuccessful response, the second step is the operative treatment with open and arthroscopic techniques. The aim of the study is to describe different MR imaging patterns, comparing our data with those reported in the literature, in order to identify the best accurate diagnostic protocol.

Synthesis, pharmacological evaluation, and structure-activity relationship and quantitative structure-activity relationship studies on novel derivatives of 2,4-diamino-6,7-dimethoxyquinazoline alpha1-adrenoceptor antagonists

A new series of novel piperazine and non-piperazine derivatives of 2, 4-diamino-6,7-dimethoxyquinazoline was synthesized and evaluated for binding affinity toward alpha1-adrenergic and other G-protein-coupled aminergic receptors. The alpha1-adrenoceptor (AR) subtype selectivity was also investigated for the most interesting compounds. Only compound 16 showed moderate selectivity toward the alpha1b-AR subtype. Selected compounds were tested in vivo in a dog model indicating activity on blood pressure and on the lower urinary tract. Compound 10 showed in vivo potency close to that of prazosin. Powerful interpretative and predictive theoretical QSAR models have been obtained. The theoretical descriptors employed in the rationalization of the alpha1-adrenergic binding affinity depict the key features for receptor binding which can be summarized in an electrostatic interaction between the protonated amine function and a primary nucleophilic site of the receptor, complemented by short-range attractive (polar and dispersive) and repulsive (steric) intermolecular interactions. Moreover, on predictive grounds, the ad hoc derived size and shape QSAR model developed in a previous paper (Rastelli, G.; et al. J. Mol. Struct. 1991, 251, 307-318) proved to be successful in predicting nanomolar alpha1-adrenergic binding affinity for compound 28.