17 research outputs found
A scientific and Archivistic investigation on Italian scagliola altar frontals
analyses of some pigments found in fragments, many dyes and pigments have been identified and the technique clarifie
A scientific and historical investigation on Italian scagliola
Fragments from works of art made of scagliola, a material typical of northern Italy imitating marble, were investigated. Thefragments are representative of art objects that were once widespread in the region centred on the town of Carpi. Vibrationalspectroscopic techniques were applied in order to identify the pigments used to tint the gypsum paste; in particular, Ramanmicroscopy was used for the identification of pigment particles. Pyrolysis gas chromatography combined with mass spectroscopy wasused to identify binding media. Several documents were examined, both ancient and recent, preserved in local archives, describingthe pigments and dyes and the techniques used in the preparation of scagliola. The information provided in these documents wascompared to results obtained from scientific analysis
Il monitoraggio biologico del cobalto quale metodo di misura per esposizioni professionali ed ambientali dicirca 4 mesi
Dati sulla cinetica del Co nel sangue in un gruppo di 32 lavoratori esposti attraverso il monitoraggio per 16 settimane consecutive degli addotti del cobalto alla globin
Visible light photocatalysis in the late-stage functionalization of pharmaceutically relevant compounds
The late stage functionalization (LSF) of complex biorelevant compounds is a powerful tool to speed up the identification of structure-Activity relationships (SARs) and to optimize ADME profiles. To this end, visible-light photocatalysis offers unique opportunities to achieve smooth and clean functionalization of drugs by unlocking site-specific reactivities under generally mild reaction conditions. This review offers a critical assessment of current literature, pointing out the recent developments in the field while emphasizing the expected future progress and potential applications. Along with paragraphs discussing the visible-light photocatalytic synthetic protocols so far available for LSF of drugs and drug candidates, useful and readily accessible synoptic tables of such transformations, divided by functional groups, will be provided, thus enabling a useful, fast, and easy reference to them
Cleft lip and/or palate : Review
Aim. Aim of the review was to provide a literature overview of the birth defects of cleft lip and/or cleft palate (CL/P). Methods. Through the use of the PubMed database items were collected that would provide information about the condition, leading to the discussion of the following topics: epidemiology, anatomical features, genetics, environmental factors, diagnosis and treatment. Results. According to these data, the CL/P are the most common congenital malformations of the craniofacial region. There are different phenotypes and clinical features of this malformation, which differ according to the anatomical structures involved: cleft lip, cleft lip and cleft palate. The etiology is multifactorial and includes both genetic factors and environmental factors. For proper diagnosis and treatment it is important to complete a multidisciplinary approach to guide the patient from birth to the end of growth. Among the outstanding figures for the care of the anomaly are: the gynecologist, the pediatrician, the maxillofacial surgeon and orthodontist. Individuals with a cleft lip and/or cleft palate may experience problems in feeding, pronunciation, hearing and social integration, which can be corrected to a different extent by surgery, dental treatment, speech therapy and psychosocial interventions. Conclusion. Today the optimal treatment is difficult to find, because of the large variability of malformations and the subjective response of each patient to therapy
Modifications on C6 and C7 Positions of 3-Phenylquinolone Efflux Pump Inhibitors Led to Potent and Safe Antimycobacterial Treatment Adjuvants
Nontuberculous mycobacteria (NTM) are ubiquitous microbes belonging to the Mycobacterium genus. Among all NTM pathogens, M. avium is one of the most frequent agents causing pulmonary disease, especially in immunocompromised individuals and cystic fibrosis patients. Recently, we reported the first ad hoc designed M. avium efflux pump inhibitor (EPI; 1b) able to strongly boost clarithromycin (CLA) MIC against different M. avium strains. Since the 3-phenylquinolone derivative 1b suffered from toxicity issues toward human macrophages, herein we report a two-pronged medicinal chemistry workflow for identifying new potent and safe NTM EPIs. Initially, we followed a computational approach exploiting our pharmacophore models to screen FDA approved drugs and in-house compounds to identify "ready-to-use" NTM EPIs and/or new scaffolds to be optimized in terms of EPI activity. Although nicardipine 2 was identified as a new NTM EPI, all identified molecules still suffered from toxicity issues. Therefore, based on the promising NTM EPI activity of 1b, we undertook the design, synthesis, and biological evaluation of new 3-phenylquinolones differently functionalized at the C6/C7 as well as N1 positions. Among the 27 synthesized 3-phenylquinolone analogues, compounds 11b, 12b, and 16a exerted excellent NTM EPI activity at concentrations below their CC50 on human cells, with derivative 16a being the most promising compound. Interestingly, 16a also showed good activity in M. avium-infected macrophages both alone as well as in combination with CLA. The antimycobacterial activity observed for 16a only when tested in the ex vivo model suggests a high therapeutic potential of EPIs against M. avium, which seems to need functional efflux pumps to establish intracellular infections
Studies on 2-phenylquinoline Staphylococcus aureus NorA efflux pump inhibitors: New insights on the C-6 position
The alarming and rapid spread of antimicrobial resistance among bacteria represents a high risk for global health. Targeting factors involved in resistance to restore the activity of failing antibiotics is a promising strategy to overcome this urgent medical need. Efflux pump inhibitors are able to increase antibiotic concentrations in bacteria, thus they can be considered true antimicrobial resistance breakers. In this work, continuing our studies on inhibitors of the Staphylococcus aureus NorA pump, we designed, synthesized and biologically evaluated novel 2-phenylquinoline derivatives starting from our hits 1 and 2. Two of the synthesized compounds (6 and 7) bearing a C-6 benzyloxy group showed the best NorA inhibition activity, thereby providing an excellent starting point to direct future chemical optimizations
C-2 phenyl replacements to obtain potent quinoline-based Staphylococcus aureus NorA inhibitors
NorA is the most studied efflux pump of Staphylococcus aureus and is responsible for high level resistance towards fluoroquinolone drugs. Although along the years many NorA efflux pump inhibitors (EPIs) have been reported, poor information is available about structure-activity relationship (SAR) around their nuclei and reliability of data supported by robust assays proving NorA inhibition. In this regard, we focussed efforts on the 2-phenylquinoline as a promising chemotype to develop potent NorA EPIs. Herein, we report SAR studies about the introduction of different aryl moieties on the quinoline C-2 position. The new derivative 37a showed an improved EPI activity (16-fold) with respect to the starting hit 1. Moreover, compound 37a exhibited a high potential in time-kill curves when combined with ciprofloxacin against SA-1199B (norA+). Also, 37a exhibited poor non-specific effect on bacterial membrane polarisation and showed an improvement in terms of “selectivity index” in comparison to 1
Identification of Inhibitors of SARS-CoV-2 3CL-Pro Enzymatic Activity Using a Small Molecule in Vitro Repurposing Screen
Compound repurposing is an important strategy for the identification of effective treatment options against SARS-CoV-2 infection and COVID-19 disease. In this regard, SARS-CoV-2 main protease (3CL-Pro), also termed M-Pro, is an attractive drug target as it plays a central role in viral replication by processing the viral polyproteins pp1a and pp1ab at multiple distinct cleavage sites. We here report the results of a repurposing program involving 8.7 K compounds containing marketed drugs, clinical and preclinical candidates, and small molecules regarded as safe in humans. We confirmed previously reported inhibitors of 3CL-Pro and have identified 62 additional compounds with IC50 values below 1 μM and profiled their selectivity toward chymotrypsin and 3CL-Pro from the Middle East respiratory syndrome virus. A subset of eight inhibitors showed anticytopathic effect in a Vero-E6 cell line, and the compounds thioguanosine and MG-132 were analyzed for their predicted binding characteristics to SARS-CoV-2 3CL-Pro. The X-ray crystal structure of the complex of myricetin and SARS-Cov-2 3CL-Pro was solved at a resolution of 1.77 Å, showing that myricetin is covalently bound to the catalytic Cys145 and therefore inhibiting its enzymatic activity