Pesticides monitoring in biological fluids: Mapping the gaps in analytical strategies

Pesticides play a key-role in the development of the agrifood sector allowing controlling pest growth and, thus, improving the production rates. Pesticides chemical stability is responsible of their persistency in environmental matrices leading to bioaccumulation in animal tissues and hazardous several effects on living organisms. The studies regarding long-term effects of pesticides exposure and their toxicity are still limited to few studies focusing on over-exposed populations, but no extensive dataset is currently available. Pesticides biomonitoring relies mainly on chromatographic techniques coupled with mass spectrometry, whose large-scale application is often limited by feasibility constraints (costs, time, etc.). On the contrary, chemical sensors allow rapid, in-situ screening. Several sensors were designed for the detection of pesticides in environmental matrices, but their application in biological fluids needs to be further explored. Aiming at contributing to the implementation of pesticides biomonitoring methods, we mapped the main gaps between screening and chromatographic methods. Our overview focuses on the recent advances (2016-2021) in analytical methods for the determination of commercial pesticides in human biological fluids and provides guidelines for their application.

Cationic palladium(II)-indenyl complexes bearing phosphines as ancillary ligands: synthesis, and study of indenyl amination and anticancer activity

The reactivity of palladium(II) indenyl derivatives and their applications are topics relatively less studied, though in recent times these compounds have been used as pre-catalysts able to promote challenging cross-coupling processes. Herein, we propose the first systematic study concerning the nucleophilic attack on the palladium(II) coordinated indenyl fragment and, for this purpose, we have prepared a library of new Pd-indenyl complexes bearing mono- or bidentate phosphines as spectator ligands, developing specific synthetic strategies. All novel compounds are thoroughly characterized, highlighting that the indenyl ligand presents always a hapticity intermediate between η³ and η⁵. Secondary amines have been chosen as nucleophiles for the present study and indenyl amination has been monitored by UV-Vis and NMR spectroscopies, deriving a second order rate law, with dependence on both complex and amine concentrations. The rate-determining step of the process is the initial attack of the amine to the coordinated indenyl fragment, and this conclusion has been supported also by DFT calculations. The determination of second order rate constants has allowed us to assess the impact of the phosphine ligands on the kinetics of the process and identify the steric and electronic descriptors most suitable for predicting the reactivity of these systems. Finally, in vitro tests have proven that these organometallic compounds promote antiproliferative activity towards ovarian cancer cells better than cisplatin and possibly by adopting a different mechanism of action.

Uncommon clinical presentation of Kimura’s disease as bilateral retroauricular masses in a young Malian male: successful surgical approach

We present a case of a 27 year-old Malian male referred to our hospital for two large, painless retroauricolar masses that had appeared two years earlier. Bilateral cervical painless lymphadenopathy was present at physical examination, without any other systemic symptoms. His history was relevant for bilateral Kimura’s disease lesions resected 5 years earlier in the same locations. Lymphocytosis and a mild hypereosinophilia were found in routine blood tests, together with increased total IgE levels. After surgery, histology showed lymphoid infiltrates with reactive prominent germinal centres containing eosinophils, suggesting relapse of Kimura’s disease, in the context of nonencapsulated fibrous proliferation with discontinuous collagen fibers, consistent with keloid. Three months after removal of retroauricular masses, abnormal laboratory findings reverted to normal. To the best our knowledge, this is the first case in literature of bilateral keloid lesions developed after surgery for Kimura Disease and harbouring its histopathologic features. Clinicians should be aware of these unusual reactive phenomena and their possible simulators.