Can We Exploit β-Lactamases Intrinsic Dynamics for Designing More Effective Inhibitors?

β-lactamases (BLs) represent the most frequent cause of antimicrobial resistance in Gram-negative bacteria. Despite the continuous efforts in the development of BL inhibitors (BLIs), new BLs able to hydrolyze the last developed antibiotics rapidly emerge. Moreover, the insurgence rate of effective mutations is far higher than the release of BLIs able to counteract them. This results in a shortage of antibiotics that is menacing the effective treating of infectious diseases. The situation is made even worse by the co-expression in bacteria of BLs with different mechanisms and hydrolysis spectra, and by the lack of inhibitors able to hit them all. Differently from other targets, BL flexibility has not been deeply exploited for drug design, possibly because of the small protein size, for their apparent rigidity and their high fold conservation. In this mini-review, we discuss the evidence for BL binding site dynamics being crucial for catalytic efficiency, mutation effect, and for the design of new inhibitors. Then, we report on identified allosteric sites in BLs and on possible allosteric inhibitors, as a strategy to overcome the frequent occurrence of mutations in BLs and the difficulty of competing efficaciously with substrates. Nevertheless, allosteric inhibitors could work synergistically with traditional inhibitors, increasing the chances of restoring bacterial susceptibility towards available antibiotics

Comparative study of three low-tech soilless systems for the cultivation of geranium (Pelargonium zonale): A commercial quality assessment

The study evaluated the feasibility of simplified hydroponics for the growth of rooted cuttings of geranium (Pelargonium zonale) for commercial purposes in local farms in Northern Italy. Tested systems included a control where soilless system on substrate (peat) (T-1), usually adopted by local farmers, was compared against an open-cycle drip system on substrate (peat) (T-2), and a Nutrient Film Technique system (T-3). For commercial features, assessed parameters included flowering degree (flowering timing, numbers of inflorescences plant−1, and number of flowers inflorescence−1), numbers of leaves plant−1, number of branches plant−1, final height of plant, and the aesthetic-commercial assessment index. Assessed parameters also included fresh and dry weight, SPAD Index, the water consumption, and the water use efficiency (WUE). The soilless systems typology significantly affected rooted cuttings growth, commercial features, and WUE. The adoption of an open-cycle drip system (T-2) resulted in a significant improvement of all the crop commercial characteristics as compared with other treatments, making plants more attractive for the market. The water consumption was higher in T-2 as compared with T-1 and T-3, but it allowed for the highest fresh weight, and therefore also the highest WUE. The results indicate that the typology of soilless system significantly enhances the commercial characteristics of geranium

Eco-efficiency assessment and food security potential of home gardening: a case study in Padua, Italy

In the expanding urban agriculture phenomenon in Europe, home gardens are a traditional form that have kept agriculture within cities, even becoming crucial in certain historical periods (e.g., war periods). However, horticultural practices in home gardens can also have negative consequences. The goal of this paper is to assess the eco-efficiency of home gardens as a type of urban agriculture. To do so, a case study in Padua (Italy) was evaluated following life cycle assessment and life cycle costing methods. A home garden of 30.6 m(2) and 21 crop cycles were evaluated. The functional unit of the assessment was 1 kg of harvested fresh vegetable at the consumption point, and the ReCiPe method was employed for impact assessment. Environmental assessment indicated that organic fertilization, use of tap water, mineral fertilization and pesticides were the most contributing elements of the entire life cycle. Furthermore, the relevance of garden design and crop selection was a determinant in the eco-efficiency results. The assessed home garden could satisfy the food requirements of between 1 and 2 members of the household. Crop management and design recommendations are provided to improve eco-efficiency and food security potential of home gardens

Improving water use efficiency in vertical farming: Effects of growing systems, far-red radiation and planting density on lettuce cultivation

Vertical farms (VFs) are innovative urban production facilities consisting of multi-level indoor systems equipped with artificial lighting in which all the environmental conditions are controlled independently from the external climate. VFs are generally provided with a closed loop fertigation system to optimize the use of water and nu-trients. The objective of this study, performed within an experimental VF at the University of Bologna, was to quantify the water use efficiency (WUE, ratio between plant fresh weight and the volume of water used) for a lettuce (Lactuca sativa L.) growth cycle obtained in two different growing systems: an ebb-and-flow substrate culture and a high pressure aeroponic system. Considering the total water consumed (water used for irrigation and climate management), WUE of ebb-and-flow and aeroponics was 28.1 and 52.9 g L-1 H2O, respectively. During the growing cycle, the contribution generated by the recovery of internal air moisture from the heating, ventilation and air conditioning (HVAC) system, was quantified. Indeed, by recovering water from the dehu-midifier, water use decreases dramatically (by 67 %), while WUE increased by 206 %. Further improvement of WUE in the ebb-and-flow system was obtained through ameliorated crop management strategies, in particular, by increasing planting densities (e.g., 153, 270 and 733 plants m-2) and by optimizing the light spectrum used for plant growth (e.g., adjusting the amount of far-red radiation in the spectrum). Strategies for efficient use of water in high-tech urban indoor growing systems are therefore proposed

Structure-Based Optimization of 1,2,4-Triazole-3-Thione Derivatives: Improving Inhibition of NDM-/VIM-Type Metallo-β-Lactamases and Synergistic Activity on Resistant Bacteria

: The worldwide emergence and dissemination of Gram-negative bacteria expressing metallo-β-lactamases (MBLs) menace the efficacy of all β-lactam antibiotics, including carbapenems, a last-line treatment usually restricted to severe pneumonia and urinary tract infections. Nonetheless, no MBL inhibitor is yet available in therapy. We previously identified a series of 1,2,4-triazole-3-thione derivatives acting as micromolar inhibitors of MBLs in vitro, but devoid of synergistic activity in microbiological assays. Here, via a multidisciplinary approach, including molecular modelling, synthesis, enzymology, microbiology, and X-ray crystallography, we optimized this series of compounds and identified low micromolar inhibitors active against clinically relevant MBLs (NDM-1- and VIM-type). The best inhibitors increased, to a certain extent, the susceptibility of NDM-1- and VIM-4-producing clinical isolates to meropenem. X-ray structures of three selected inhibitors in complex with NDM-1 elucidated molecular recognition at the base of potency improvement, confirmed in silico predicted orientation, and will guide further development steps

Virtual screening identifies broad-spectrum \u3b2-lactamase inhibitors with activity on clinically relevant serine- and metallo-carbapenemases

Bacteria are known to evade \u3b2-lactam antibiotic action by producing \u3b2-lactamases (BLs), including carbapenemases, which are able to hydrolyze nearly all available \u3b2-lactams. The production of BLs represents one of the best known and most targeted mechanisms of resistance in bacteria. We have performed the parallel screening of commercially available compounds against a panel of clinically relevant BLs: class A CTX-M-15 and KPC-2, subclass B1 NDM-1 and VIM-2 MBLs, and the class C P. aeruginosa AmpC. The results show that all BLs prefer scaffolds having electron pair donors: KPC-2 is preferentially inhibited by sulfonamide and tetrazole-based derivatives, NDM-1 by compounds bearing a thiol, a thiosemicarbazide or thiosemicarbazone moiety, while VIM-2 by triazole-containing molecules. Few broad-spectrum BLs inhibitors were identified; among these, compound 40 potentiates imipenem activity against an NDM-1-producing E. coli clinical strain. The binary complexes of the two most promising compounds binding NDM-1 and VIM-2 were obtained at high resolution, providing strong insights to improve molecular docking simulations, especially regarding the interaction of MBLs with inhibitors

Burden of paediatric Rotavirus Gastroenteritis (RVGE) and potential benefits of a universal Rotavirus vaccination programme with a pentavalent vaccine in Spain

<p>Abstract</p> <p>Background</p> <p>Rotavirus is the most common cause of gastroenteritis in young children worldwide. The aim of the study was to assess the health outcomes and the economic impact of a universal rotavirus vaccination programme with RotaTeq, the pentavalent rotavirus vaccine, versus no vaccination programme in Spain.</p> <p>Methods</p> <p>A birth cohort was followed up to the age of 5 using a cohort model. Epidemiological parameters were taken from the REVEAL study (a prospective epidemiological study conducted in Spain, 2004-2005) and from the literature. Direct and indirect costs were assessed from the national healthcare payer and societal perspectives by combining health care resource utilisation collected in REVEAL study and unit costs from official sources. RotaTeq per protocol efficacy data was taken from a large worldwide rotavirus clinical trial (70,000 children). Health outcomes included home care cases, General Practioner (GP)/Paediatrician, emergency department visits, hospitalisations and nosocomial infections.</p> <p>Results</p> <p>The model estimates that the introduction of a universal rotavirus vaccination programme with RotaTeq (90% coverage rate) would reduce the rotavirus gastroenteritis (RVGE) burden by 75% in Spain; 53,692 home care cases, 35,187 GP/Paediatrician visits, 34,287 emergency department visits, 10,987 hospitalisations and 2,053 nosocomial infections would be avoided. The introduction of RotaTeq would avoid about 76% of RVGE-related costs from both perspectives: €22 million from the national health system perspective and €38 million from the societal perspective.</p> <p>Conclusions</p> <p>A rotavirus vaccination programme with RotaTeq would reduce significantly the important medical and economic burden of RVGE in Spain.</p

Oncoplastic and reconstructive surgery in SENONETWORK Italian breast centers: lights and shadows

Highlights: • Despite the significance of oncoplastic procedure, an italian database is lacking. • Senonetwork established a multidisciplinary survey to assess their safety and efficacy. • Reconstructive outcomes were positive across low and high-volume centers. • After mastectomy, implant-based techniques are common. DTI reconstruction is advantageuos. • This contributes to the global understanding of effective strategies against breast cancer

Techniques and crops for efficient rooftop gardens in Bologna, Italy

Urban rooftop farming favours local food production. Although rooftop farming is perceived as 33 a sustainable system, there is a lack of quantitative studies on rooftop farming. There we set up 34 experiments in the community rooftop garden of a public housing building in Bologna, Italy, 35 between 2012 and 2014. We grew lettuce, a leafy vegetable, using three techniques: nutrient 36 film, floating hydroponic and soil cultivation. We also grew tomato, chilli pepper, eggplant, 37 melon, watermelon on soils. Data was analysed by life cycle assessment for environmental and 38 economic performance. Results reveal that the best techniques of lettuce cultivation to address 39 global warming were floating in the summer, with 65-85% less environmental impact per kg 40 than nutrient film; and soil production in the winter, with 85-95% less environmental impact. 41 Furthermore, floating production was 25% cheaper in summer and soil was 65% cheaper in 42 winter, compared to the nutrient film technique. For soil production, eggplants and tomatoes 43 showed the best environmental performances of about 74 g CO2 per kg. Eggplant production in 44 soil gave in the cheapest crop of 0.13 € per kg

A community effort in SARS-CoV-2 drug discovery.

peer reviewedThe COVID-19 pandemic continues to pose a substantial threat to human lives and is likely to do so for years to come. Despite the availability of vaccines, searching for efficient small-molecule drugs that are widely available, including in low- and middle-income countries, is an ongoing challenge. In this work, we report the results of an open science community effort, the "Billion molecules against Covid-19 challenge", to identify small-molecule inhibitors against SARS-CoV-2 or relevant human receptors. Participating teams used a wide variety of computational methods to screen a minimum of 1 billion virtual molecules against 6 protein targets. Overall, 31 teams participated, and they suggested a total of 639,024 molecules, which were subsequently ranked to find 'consensus compounds'. The organizing team coordinated with various contract research organizations (CROs) and collaborating institutions to synthesize and test 878 compounds for biological activity against proteases (Nsp5, Nsp3, TMPRSS2), nucleocapsid N, RdRP (only the Nsp12 domain), and (alpha) spike protein S. Overall, 27 compounds with weak inhibition/binding were experimentally identified by binding-, cleavage-, and/or viral suppression assays and are presented here. Open science approaches such as the one presented here contribute to the knowledge base of future drug discovery efforts in finding better SARS-CoV-2 treatments.R-AGR-3826 - COVID19-14715687-CovScreen (01/06/2020 - 31/01/2021) - GLAAB Enric