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Patients with acute stroke often require venous access to facilitate diagnostic investigations or intravenous therapy. The primary aim of this study was to describe the rate and type of complications associated with the placement of a short peripheral catheter (SPC) in patients with acute ischemic or hemorrhagic stroke. A prospective, observational, single-cohort study was conducted at Niguarda Hospital, Italy, with enrolment in the Emergency Department. Adult patients with an ischemic or hemorrhagic stroke requiring an SPC were enrolled. Complications, such as infiltration, occlusion, phlebitis and dislodgment, were recorded daily. Descriptive statistics were used, and the incidence rate ratio (IRR) was estimated to assess the difference in complications, considering catheter calibre, dominant side, exit site, limb, and limb mobility, ictus type (ischemic/haemorrhagic), impairment deficit (language, motor, visual) and EA-DIVA score. A total of 269 participants and 755 SPC were analysed. Removal of SPC due to at least one local complication occurred in 451 (60%). Dislodgment was the major cause of SPC removal (31%), followed by infiltration (18%), occlusion (6%), and phlebitis (5%). The SPC calibre (22G), exit-site other than antecubital and forearm, visual deficit and EA-DIVA ≥ 8 were associated with a higher rate of SPC complications: IRR, 1.71 [1.31; 2.31]; 1.27 [1.01; 1.60], 1.38 [1.06; 1.80], 1.30 [1.04; 1.64], respectively. No other differences in complication rates were observed according to the insertion site, i.e. dominant side, left side, plegic/hyposthenic limb, or exit site. This study provides novel insights into the frequency and types of complications associated with SPC in patients with acute stroke. Compared to the literature, a higher dislodgment rate was observed, being the first cause of SPC removal, whereas no differences in the number of infiltrations, occlusions, and phlebitis were recorded.

Histone deacetylase 6 (HDAC6) is increasingly recognized for its potential in targeted disease therapy. This study delves into the mechanistic and structural nuances of HDAC6 inhibition by difluoromethyl-1,3,4-oxadiazole (DFMO) derivatives, a class of non-hydroxamic inhibitors with remarkable selectivity and potency. Employing a combination of nuclear magnetic resonance (NMR) spectroscopy and liquid chromatography-mass spectrometry (LC-MS) kinetic experiments, comprehensive enzymatic characterizations, and X-ray crystallography, we dissect the intricate details of the DFMO-HDAC6 interaction dynamics. More specifically, we find that the chemical structure of a DMFO and the binding mode of its difluoroacetylhydrazide derivative are crucial in determining the predominant hydrolysis mechanism. Our findings provide additional insights into two different mechanisms of DFMO hydrolysis, thus contributing to a better understanding of the HDAC6 inhibition by oxadiazoles in disease modulation and therapeutic intervention.

FimH is a mannose-specific adhesin that mediates the adhesion of uropathogenic Escherichia coli (UPEC) to urothelial cells and can be targeted thanks to the glycoside cluster effect given by carbohydrate-lectin interactions [1]. Among the different synthetic scaffolds used to build multivalent glycoconjugates [2], calixarenes show peculiar properties dependent on the different valences of the scaffold and on the stereochemical disposition of the saccharide units. Thus, we inserted two trivalent mannosylated dendrons onto the upper rim of a calix[4]arene scaffold, obtaining hexavalent glycocalixarenes (Figure 1). The antiadhesive properties of compounds 5a-b was then assessed by an assay based on yeast cell agglutination to UPEC, a highly conserved FimH-dependent binding property among isolated E. coli strains. On-cell STD NMR experiments, acquired in the presence of UPEC living cells, confirmed the specific binding of calixarenes functionalized with Man units (5a-b) to FimH proteins at the cell surface [3]. Mannosylated calixarenes 5a-b are thus promising hit compounds for the development of novel antiadhesive therapies aimed at fighting urinary tract infections caused by UPEC. [1] S. N. Abraham, D. Sun, J. B. Dale, E. H. Beachey, Nature 1988, 336, 682 – 684 [2] A. Palmioli, P. Sperandeo, S. Bertuzzi, A. Polissi, C. Airoldi, Bioorg. Chem. 2021, 112 [3] A. Palmioli, L. Moretti, C. A. Vezzoni, L. Legnani, P. Sperandeo, L. Baldini, F. Sansone, C. Airoldi, A. Casnati, Bioorg. Chem. 2023, 138

Antimicrobial resistance emerges as a threat in 21st century, with available antibiotics exerting selective pressure on essential pathways, favoring resistance development across bacterial species. The broad-spectrum nature of most antibiotics compounds the issue, causing lasting harm to the healthy human microbiota. In addition to the development of novel antibacterial molecules exploiting new mechanisms of action, to counteract this alarming scenario there is urgent need for: a) diagnostic tools for a fast identification of pathogen classes (Gram+, Gram-, mycobacteria) to timely select the most suitable antibiotic class. b) novel drugs “disarming” pathogenic bacteria by disrupting their virulence mechanisms, such as those enabling bacteria to colonize, evade or inhibit the host's immune response, and scavenge nutrients. Compounds targeting virulence processes promise reduced evolutionary pressure for resistance, supplementing conventional antibiotics with increased efficacy and minimal impact on the host commensal flora. In pursuit of these goals, we are pioneering the development of multivalent bacteria ligands. These ligands, based on calixarene or dendrimer scaffolds, target specific molecular patterns in different bacteria classes. Examples include the terminal part of peptidoglycan (D-Ala-D-Ala) and teichoic acids for Gram+ bacteria, LPS for Gram- bacteria, and mycolic acid, glycolipids, and trehalose transporter for mycobacteria. Moreover, for a specific pathogen targeting, the adhesin FimH located at the pili end of an uropathogenic strain of Escherichia coli can be targeted through the glycoside cluster effect of carbohydrate-lectin interactions. Our advanced screening approach, using on-cell STD NMR experiments, has successfully identified promising hit compounds as selective bacteria ligands and anti-virulence factors.

Spinocerebellar ataxia type 3 (SCA3) is a neurodegenerative disorder characterized by ataxia and other neurological manifestations, with a poor prognosis and a lack of effective therapies. The amyloid aggregation of the ataxin-3 protein is a hallmark of SCA3 and one of the main biochemical events prompting its onset, making it a prominent target for the development of preventive and therapeutic interventions. Here, we tested the efficacy of an aqueous Lavado cocoa extract and its polyphenolic components against ataxin-3 aggregation and neurotoxicity. The combination of biochemical assays and atomic force microscopy morphological analysis provided clear evidence of cocoa flavanols’ ability to hinder ATX3 amyloid aggregation through direct physical interaction, as assessed by NMR spectroscopy. The chemical identity of the flavanols was investigated by ultraperformance liquid chromatography-high-resolution mass spectrometry. The use of the preclinical model Caenorhabditis elegans allowed us to demonstrate cocoa flavanols’ ability to ameliorate ataxic phenotypes in vivo. To the best of our knowledge, Lavado cocoa is the first natural source whose extract is able to directly interfere with ATX3 aggregation, leading to the formation of off-pathway species.

The aggregation of amyloid peptides and proteins into toxic oligomers is a hallmark of neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease, Machado-Joseph's disease, and transmissible spongiform encephalopathies. Inhibition of amyloid oligomers formation and interactions with biological counterparts, as well as the triggering of non-toxic amorphous aggregates, are strategies towards preventive interventions against these pathologies. NMR spectroscopy addresses the need for structural characterization of amyloid proteins and their aggregates, their binding to inhibitors, and rapid screening of compound libraries for ligand identification. Here we briefly discuss the solution experiments constituting the NMR spectroscopist‘s toolkit and provide examples of their application.

In Antarctica, ice-free areas can be found along the coast, on mountain peaks, and in the McMurdo Dry Valleys, where microorganisms well-adapted to harsh conditions can survive and reproduce. Metabolic analyses can shed light on the survival mechanisms of Antarctic soil communities from both coastal sites, under different plant coverage stages, and inner sites where slow-growing or dormant microorganisms, low water availability, salt accumulation, and a limited number of primary producers make metabolomic profiling difficult. Here, we report, for the first time, an efficient protocol for the extraction and the metabolic profiling of Antarctic soils based on the combination of NMR spectroscopy and mass spectrometry (MS). This approach was set up on samples harvested along different localities of Victoria Land, in continental Antarctica, devoid of or covered by differently developed biological crusts. NMR allowed for the identification of thirty metabolites (mainly sugars, amino acids, and organic acids) and the quantification of just over twenty of them. UPLC-MS analysis identified more than twenty other metabolites, in particular flavonoids, medium- and long-chain fatty acids, benzoic acid derivatives, anthracenes, and quinones. Our results highlighted the complementarity of the two analytical techniques. Moreover, we demonstrated that their combined use represents the “gold standard” for the qualitative and quantitative analysis of little-explored samples, such as those collected from Antarctic soils.

Objectives: To investigate the inter/intra-reliability of ultrasound (US) muscle echogenicity in patients with rheumatic diseases. Methods: Forty-two rheumatologists and 2 radiologists from 13 countries were asked to assess US muscle echogenicity of quadriceps muscle in 80 static images and 20 clips from 64 patients with different rheumatic diseases and 8 healthy subjects. Two visual scales were evaluated, a visual semi-quantitative scale (0–3) and a continuous quantitative measurement (“VAS echogenicity,” 0–100). The same assessment was repeated to calculate intra-observer reliability. US muscle echogenicity was also calculated by an independent research assistant using a software for the analysis of scientific images (ImageJ). Inter and intra reliabilities were assessed by means of prevalence-adjusted bias-adjusted Kappa (PABAK), intraclass correlation coefficient (ICC) and correlations through Kendall’s Tau and Pearson’s Rho coefficients. Results: The semi-quantitative scale showed a moderate inter-reliability [PABAK = 0.58 (0.57–0.59)] and a substantial intra-reliability [PABAK = 0.71 (0.68–0.73)]. The lowest inter and intra-reliability results were obtained for the intermediate grades (i.e., grade 1 and 2) of the semi-quantitative scale. “VAS echogenicity” showed a high reliability both in the inter-observer [ICC = 0.80 (0.75–0.85)] and intra-observer [ICC = 0.88 (0.88–0.89)] evaluations. A substantial association was found between the participants assessment of the semi-quantitative scale and “VAS echogenicity” [ICC = 0.52 (0.50–0.54)]. The correlation between these two visual scales and ImageJ analysis was high (tau = 0.76 and rho = 0.89, respectively). Conclusion: The results of this large, multicenter study highlighted the overall good inter and intra-reliability of the US assessment of muscle echogenicity in patients with different rheumatic diseases.

We report the synthesis and biological characterization of a novel class of multivalent glycoconjugates as hit compounds for the design of new antiadhesive therapies against urogenital tract infections (UTIs) caused by uropathogenic E. coli strains (UPEC). The first step of UTIs is the molecular recognition of high mannose N-glycan expressed on the surface of urothelial cells by the bacterial lectin FimH, allowing the pathogen adhesion required for mammalian cell invasion. The inhibition of FimH-mediated interactions is thus a validated strategy for the treatment of UTIs. To this purpose, we designed and synthesized D-mannose multivalent dendrons supported on a calixarene core introducing a significant structural change from a previously described family of dendrimers bearing the same dendrons units on a flexible pentaerythritol scaffold core. The new molecular architecture increased the inhibitory potency against FimH-mediated adhesion processes by about 16 times, as assessed by yeast agglutination assay. Moreover, the direct molecular interaction of the new compounds with FimH protein was assessed by on-cell NMR experiments acquired in the presence of UPEC cells.

Objectives. To investigate the reliability of the OMERACT US Task Force definition of US enthesitis in SpA. Methods. In this web exercise, based on the evaluation of 101 images and 39 clips of the main entheses of the lower limbs, the elementary components included in the OMERACT definition of US enthesitis in SpA (hypoechoic areas, entheseal thickening, power Doppler signal at the enthesis, enthesophytes/calcifications, bone erosions) were assessed by 47 rheumatologists from 37 rheumatology centres in 15 countries. Inter- and intra-observer reliability of the US components of enthesitis was calculated using Light’s kappa, Cohen’s kappa, Prevalence And Bias Adjusted Kappa (PABAK) and their 95% CIs. Results. Bone erosions and power Doppler signal at the enthesis showed the highest overall inter-reliability [Light’s kappa: 0.77 (0.76–0.78), 0.72 (0.71–0.73), respectively; PABAK: 0.86 (0.86–0.87), 0.73 (0.73–0.74), respectively], followed by enthesophytes/calcifications [Light’s kappa: 0.65 (0.64–0.65), PABAK: 0.67 (0.67–0.68)]. This was moderate for entheseal thickening [Light’s kappa: 0.41 (0.41–0.42), PABAK: 0.41 (0.40–0.42)], and fair for hypoechoic areas [Light’s kappa: 0.37 (0.36–0.38); PABAK: 0.37 (0.37–0.38)]. A similar trend was observed in the intra-reliability exercise, although this was characterized by an overall higher degree of reliability for all US elementary components compared with the inter-observer evaluation. Conclusions. The results of this multicentre, international, web-based study show a good reliability of the OMERACT US definition of bone erosions, power Doppler signal at the enthesis and enthesophytes/calcifications. The low reliability of entheseal thickening and hypoechoic areas raises questions about the opportunity to revise the definition of these two major components for the US diagnosis of enthesitis.

Antimicrobial resistance (AMR) is one of the major threats of the 21st century (1). Available antibiotics target essential pathways imposing selective pressure that favors resistance development, even across distant bacterial species. This leads to the spread of resistance even to last-resort antibiotics. Further, the broad-spectrum nature of most antibiotics has long lasting detrimental effects on the healthy human microbiota. In addition to the development of novel antibacterial molecules exploiting new mechanisms of action, this alarming scenario requires: 1) diagnostic tools for a fast identification of the class of the pathogen (Gram+, Gram-, mycobacteria), thus allowing for a timely selection of the most appropriate antibiotic class to treat the patient; 2) novel drugs disarming pathogenic bacteria by interfering with their virulence mechanisms. Virulence factors are molecules produced by bacteria enabling them to: a) colonize a niche in the host, b) evade the host's immune response, c) inhibit the host's immune response, or d) scavenge nutrients from the host. Compounds targeting virulence processes will impose less evolutionary pressure than standard antibiotics for the development of resistance, will supplement conventional antibiotics to increase efficacy and will have little or no impact on the host commensal flora. To this aim, we are developing new multivalent bacteria ligands, based on calixarene or dendrimer scaffolds, targeting specific molecular patterns of the different bacteria classes, such as the terminal part of peptidoglycan (D-Ala-D-Ala) and teichoic acids for Gram+ bacteria, LPS for Gram- bacteria, mycolic acid, glycolipids and trehalose transporter for mycobacteria. Moreover, for a specific pathogen targeting, the adhesin FimH located at the pili end of an uropathogenic strain of Escherichia coli can be targeted through the glycoside cluster effect of carbohydrate-lectin interactions (2). An advanced approach for the screening of these bact

Introduction: Intraprocedural tip control techniques are critical during central venous catheter placement. According to international guidelines (INS 2021), intracavitary electrocardiography is the first method of choice to verify it; when this technique is not feasible, it is considered acceptable to use a contrast-enhanced ultrasound-based tip location method, commonly known as "bubble-test" as an effective alternative.Objective: To assess whether the length of the vascular catheter can alter the time between the injection of the contrast media and its appearance at the catheter tip and the injection duration. Differences between operators stratified according to experience were evaluated as secondary endpoints.Methods: A bench study was conducted using an extracorporeal circuit. For each catheter length (60, 40, and 20 cm), three injections were obtained by each of the five operators with different levels of experience for a total of 45 measurements. Differences among operators were evaluated using ANOVA, and the impact of catheter length and operator expertise on times was assessed using repeated measurement models.Results: Hub-to-tip times of 247.33 ms (SD 168.82), 166 ms (SD 95.46), 138 ms (SD 54.48), and injection duration of 1620 ms (SD 748.58), 1614 ms (SD 570.95), 1566 ms (SD 302.83) were observed for 60, 40, 20 cm catheter length, respectively. A significant time variability between operators was observed. Moreover, moving from 60 to 20 cm, hubto-tip time was significantly longer for 60 cm devices (p = 0.0124), while little differences were observed for injection duration.Conclusions: Catheter length can change both the time between the injection of the contrast media and its appearance at the catheter tip and the injection duration. Hub-to-tip times obtained with 20 and 40 cm and overall injection duration did not differ significantly; skilled personnel could substantially reduce both values analyzed in this study.

Colorectal cancer (CRC) is the second-leading cause of cancer death, with a worldwide incidence rate constantly increasing; thus, new strategies for its prevention or treatment are needed. Here, we describe the adjuvant effect of the polyphenol-enriched fractions of cinnamon, from cinnamon bark and buds, when co-administered with a potent anticancer drug, cetuximab, used for CRC therapy. The co-administration significantly reduces the cetuximab dose required for the antiproliferative activity against colorectal cancer cell line E705, which is sensitive to EGFR-targeted therapy. The anticancer activity of these cinnamon-derived fractions, whose major components (as assessed by UPLC–HRMS analysis) are procyanidins and other flavonoids, strictly correlates with their ability to induce apoptosis in cancer cell lines through ERK activation and the mitochondrial membrane potential impairment. Due to the severe side effects of cetuximab administration, our results suggest the use of nutraceuticals based on the polyphenolic fractions of cinnamon extracts as adjuvants in the therapy of CRC.

BackgroundEscherichia coli cells are the most frequently used hosts in recombinant protein production processes and mainly require molecules such as IPTG or pure lactose as inducers of heterologous expression. A possible way to reduce the production costs is to replace traditional inducers with waste materials such as cheese whey permeate (CWP). CWP is a secondary by-product generated from the production of the valuable whey proteins, which are obtained from ultrafiltration of cheese whey, a main by-product of the dairy industry, which is rich in lactose.ResultsThe effects of CWP collected from an Italian plant were compared with those of traditional inducers on the production of two model proteins (i.e., green fluorescent protein and the toxic Q55 variant of ataxin-3), in E. coli BL21 (DE3) cells. It was found that the high lactose content of CWP (165 g/L) and the antioxidant properties of its micronutrients (vitamins, cofactors and osmolytes) sustain production yields similar to those obtained with traditional inducers, accompanied by the improvement of cell fitness.ConclusionsCWP has proven to be an effective and low-cost alternative inducer to produce recombinant proteins. Its use thus combines the advantage of exploiting a waste product with that of reducing the production costs of recombinant proteins.

Proteasome inhibitors (PIs) represent the gold standard in the treatment of multiple myeloma. Among PIs, Bortezomib (BTZ) is frequently used as first line therapy, but peripheral neuropathy (PN), occurring approximately in 50% of patients, impairs their life, representing a dose-limiting toxicity. Carfilzomib (CFZ), a second-generation PI, induces a significantly less severe PN. We investigated possible BTZ and CFZ off-targets able to explain their different neurotoxicity profiles. In order to identify the possible PIs off-targets we used the SPILLO-PBSS software that performs a structure-based in silico screening on a proteome-wide scale. Among the top-ranked off-targets of BTZ identified by SPILLO-PBSS we focused on tubulin which, by contrast, did not turn out to be an off-target of CFZ. We tested the hypothesis that the direct interaction between BTZ and microtubules would inhibit the tubulin alfa GTPase activity, thus reducing the microtubule catastrophe and consequently furthering the microtubules polymerization. This hypothesis was validated in a cell-free model, since BTZ (but not CFZ) reduces the concentration of the free phosphate released during GTP hydrolysis. Moreover, NMR binding studies clearly demonstrated that BTZ, unlike CFZ, is able to interact with both tubulin dimers and polymerized form. Our data suggest that different BTZ and CFZ neurotoxicity profiles are independent from their proteasome inhibition, as demonstrated in adult mice dorsal root ganglia primary sensory neurons, and, first, we demonstrate, in a cell free model, that BTZ is able to directly bind and perturb microtubules.

In the title, it should be Oryza instead of Oriza.

Colorectal cancer (CRC) is one of the most common types of cancer, especially in Western countries, and its incidence rate is increasing every year. In this study, for the first time Vigna unguiculata L. Walp. (cowpea) water boiled seed extracts were found to reduce the viability of different colorectal cancer (CRC) cell lines, such as E705, DiFi and SW480 and the proliferation of Caco-2 line too, without affecting CCD841 healthy cell line. Furthermore, the extracts showed the ability to reduce the level of Epidermal Growth Factor Receptor (EGFR) phosphorylation in E705, DiFi and SW480 cell lines and to lower the EC50 of a CRC common drug, cetuximab, on E705 and DiFi lines from 161.7 ng mL-1 to 0.06 ng mL-1 and from 49.5 ng mL-1 to 0.2 ng mL-1 respectively. The extract was characterized in its protein and metabolite profiles by tandem mass spectrometry and 1H-NMR analyses. A Bowman-Birk protease inhibitor was identified within the protein fraction and was supposed to be the main active component. These findings confirm the importance of a legume-based diet to prevent the outbreak of many CRC and to reduce the amount of drug administered during a therapeutic cycle.

Spectroscopic non-targeted methods are gaining ever-growing importance in quality control and authenticity assessment of food products because of their strong potential for identification of specific features of the products by data-driven classifiers. One of the factors hampering the diffusion of spectroscopic non-targeted methods and data-driven classifiers is the lack of harmonized guidelines for their development and validation. In particular, to date, neither conditions to directly compare spectra recorded by different spectrometers nor studies demonstrating the statistical equivalence of the spectra are available. Among the spectroscopic analytical techniques suitable for the development of non-targeted methods, nuclear magnetic resonance (NMR) offers the unique opportunity to generate statistically equivalent signals. In this paper, the feasibility of NMR spectroscopy to generate statistically equivalent NMR signals from a number of different spectrometers was demonstrated for complex mixtures (aqueous extracts of wheat and flour) by organizing an inter-laboratory comparison involving 36 NMR spectrometers. Univariate statistics along with multivariate analysis were exploited to establish unbiased criteria for assessing the statistical equivalence of the NMR signals. The aspects affecting the signal equivalence were investigated, and possible solutions to reduce the extent of the human error were proposed and applied with satisfactory results. This study furnishes the scientific community with an appropriate and easy procedure to validate non-targeted NMR methods and provides error values to be used as a reference for future studies.

Antimicrobial resistance (AMR) is one of the major threats of the 21st century. Available antibiotics target essential pathways imposing selective pressure that favors resistance development, even across distant bacterial species. This leads to the spread of resistance even to last-resort antibiotics. Further, the broad-spectrum nature of most antibiotics has long lasting detrimental effects on the healthy human microbiota. In addition to the development of novel antibacterial molecules exploiting new mechanisms of action, this alarming scenario requires: 1) diagnostic tools for a fast identification of the class of the pathogen (Gram+, Gram-, mycobacteria), thus allowing for a timely selection of the most appropriate antibiotic class to treat the patient; 2) novel drugs disarming pathogenic bacteria by interfering with their virulence mechanisms. Virulence factors are molecules produced by bacteria enabling them to: a) colonize a niche in the host, b) evade the host's immune response, c) inhibit the host's immune response, or d) scavenge nutrients from the host. Compounds targeting virulence processes will impose less evolutionary pressure than standard antibiotics for the development of resistance, will supplement conventional antibiotics to increase efficacy and will have little or no impact on the host commensal flora. To this aim, we are developing new multivalent bacteria ligands, based on calixarene or dendrimer scaffolds, targeting specific molecular patterns of the different bacteria classes, such as the terminal part of peptidoglycan (D-Ala-D-Ala) and teichoic acids for Gram+ bacteria, LPS for Gram- bacteria, mycolic acid, glycolipids and trehalose transporter for mycobacteria. Moreover, for a specific pathogen targeting, the adhesin FimH located at the pili end of an uropathogenic strain of Escherichia coli can be targeted through the glycoside cluster effect of carbohydrate-lectin interactions. An advanced approach for the screening of these bacteria lig

Many biologically relevant molecular recognition processes are highly dynamic and rely on the equilibrium between ligands’ association and dissociation from their receptor(s), because of the reversible nature of the majority of them. Over the last few decades, several NMR experiments allowing the characterization of these interactions have been developed. They are very useful tools for the study of naturally occurring binding events, but also for the screening of both natural and synthetic compounds that, through the interaction with relevant targets, can exert biological and pharmacological activities. The aim of this chapter is to provide a general presentation of the most commonly used NMR experiments based on ligand resonance observation, together with the descriptions of specific examples of their advanced applications in the analysis of unconventional samples, such as those containing complex compound mixtures, multivalent ligands, liposomes, nanoparticles and living cells.

BACKGROUND: When helmet CPAP is performed using a Venturi system, filters are frequently interposed in the respiratory circuit to reduce noise within the helmet. The effect of the interposition of these filters on delivered fresh gas flow and the resulting FIO2 is currently unknown. METHODS: In a bench study, 2 different Venturi systems (WhisperFlow and Harol) were used to generate 3 different gas flow/FIO2 combinations (80 L/min-FIO2 0.6, 100 L/min-FIO2 0.5, 120 L/min-FIO2 0.4). Different combinations of filters were applied at the flow generator input line and/or at the helmet inlet port. Two types of filters were used for this purpose: a heat and moisture exchanger filter and an electrostatic filter. The setup without filters was used as baseline. Gas flow and FIO2 were measured for each setup. RESULTS: Compared to baseline, the interposition of filters reduced the gas flow between 1–13% (P < .001). The application of a filter at the Venturi system or at the helmet generated a comparable flow reduction (-3 ± 2% vs-4 ± 2%, P = .12), whereas a greater flow reduction (-7 ± 4%) was observed when filters were applied at both sites (P < .001). An increase in FIO2 up to 5% was observed with filters applied. A strong inverse linear relationship (P < .001) was observed between the resulting gas flow and FIO2. CONCLUSIONS: The use of filters during helmet CPAP reduced the flow delivered to the helmet and, consequently, modified FIO2. If filters are applied, an adequate gas flow should be administered to guarantee a constant CPAP during the entire respiratory cycle and avoid rebreathing. Moreover, it might be important to measure the effective FIO2 delivered to the patient to guarantee a precise assessment of oxygenation.

Ras oncoproteins play a crucial role in the onset, maintenance, and progression of the most common and deadly human cancers. Despite extensive research efforts, only a few mutant-specific Ras inhibitors have been reported. We show that cmp4-previously identified as a water-soluble Ras inhibitor- targets multiple steps in the activation and downstream signaling of different Ras mutants and isoforms. Binding of this pan-Ras inhibitor to an extended Switch II pocket on HRas and KRas proteins induces a conformational change that down-regulates intrinsic and GEF-mediated nucleotide dissociation and exchange and effector binding. A mathematical model of the Ras activation cycle predicts that the inhibitor severely reduces the proliferation of different Ras-driven cancer cells, effectively cooperating with Cetuximab to reduce proliferation even of Cetuximab-resistant cancer cell lines. Experimental data confirm the model prediction, indicating that the pan-Ras inhibitor is an appropriate candidate for medicinal chemistry efforts tailored at improving its currently unsatisfactory affinity.

Substitution with a carbon or a sulfur atom of the oxygen that in saccharides links one sugar unit to another sugar or to an aglycon generates compounds defined as C-glycosides and S-glycosides, respectively. The interest in these classes of compounds lies in the metabolic stability of the glycosidic linkage, as useful characteristic for potential drugs (inhibitors, agonists, antagonists) of glycosidic nature. After a brief introduction on the biological relevance of C-glycosides and S-glycosides, the chapter describes the different approaches for the synthesis of both classes of compounds, defining the general strategies and the recent applications. C-glycosides have been synthesized not only taking advantage of the electrophilic character of the anomeric center of the sugar, but also converting it into an electrophile or a radical. Not only carbon nucleophiles, such as organometallic reagents, carbanions, silyl enolethers, or allylsilanes, but also electrophilic carbons such as aldehydes, or carbon radical scavengers such as acrylates, can be used. The synthesis of S-glycosides is much simpler and well defined, due to the strong nucleophilic character of thiols that well combines with the electrophilic character of the anomeric center.

Peucedanum ostruthium (L.) W.D.J.Koch (Apiaceae) is an alpine medicinal plant traditionally used as a panacea to treat various ailments. For the first time, its phytotoxic and nematotoxic properties were investigated. The inhibitory activity toward germination and seedling growth of the weeds Echinochloa oryzoides (Ard.) Fritsch and Lolium multiflorum Lam. was evaluated by two in vitro assays, carried out on filter paper and soil, using different aqueous extract concentrations (1, 10, and 20 %) and 0.25 g of powder of P. ostruthium leaves, inflorescences, and rhizomes. The study showed that all samples were more effective on L. multiflorum than E. oryzoides with p-values = 0.000 on both substrate types. Nevertheless, in all cases, the soil mitigated the P. ostruthium effects. Regarding nematicidal activity, the leaf extract was the most active against larvae and adults of the nematode Panagrolaimus rigidus. According to the motility test, their death was 85.6 ± 2.7 % and 90.5 ± 3.1 % 24 h after treatment. Lastly, NMR and UPLC-HR-MS analyses led to the identification of several compounds in the aqueous extracts, including mono- and di-substituted chlorogenic acids, flavonol glycosides, coumarins, and furanocoumarin glycosides. 5-Caffeoylquinic acid was the most abundant phenolic component in all plant organs.

We describe the development of an on-cell NMR method for the rapid screening of FimH ligands and the structural identification of ligand binding epitopes. FimH is a mannose-binding bacterial adhesin expressed at the apical end of type 1 pili of uropathogenic bacterial strains and responsible for their D-mannose sensitive adhesion to host mammalian epithelial cells. Because of these properties, FimH is a key virulence factor and an attractive therapeutic target for urinary tract infection. We prepared synthetic D-mannose decorated dendrimers, we tested their ability to prevent the FimH-mediated yeast agglutination, and thus we used the compounds showing the best inhibitory activity as models of FimH multivalent ligands to set up our NMR methodology. Our experimental protocol, based on on-cell STD NMR techniques, is a suitable tool for the screening and the epitope mapping of FimH ligands aimed at the development of new antiadhesive and diagnostic tools against urinary tract infection pathogens. Notably, the study is carried out in a physiological environment, i.e. at the surface of living pathogen cells expressing FimH.

We report the rational design, synthesis, and in vitro preliminary evaluation of a new small library of non-peptide ligands of Gastrin Releasing Peptide Receptor (GRP-R), able to antagonize its natural ligand bombesin (BN) in the nanomolar range of concentration. GRP-R is a transmembrane G-protein coupled receptor promoting the stimulation of cancer cell proliferation. Being overexpressed on the surface of different human cancer cell lines, GRP-R is ideal for the selective delivery to tumor cells of both anticancer drug and diagnostic devices. What makes very challenging the design of non-peptide BN analogues is that the 3D structure of the GRP-R is not available, which is the case for many membrane-bound receptors. Thus, the design of GRP-R ligands has to be based on the structure of its natural ligands, BN and GRP. We recently mapped the BN binding epitope by NMR and here we exploited the same spectroscopy, combined with MD, to define BN conformation in proximity of biological membranes, where the interaction with GRP-R takes place. The gained structural information was used to identify a rigid C-galactosidic scaffold able to support pharmacophore groups mimicking the BN key residues’ side chains in a suitable manner for binding to GRP-R. Our BN antagonists represent hit compounds for the rational design and synthesis of new ligands and modulators of GRP-R. The further optimization of the pharmacophore groups will allow to increase the biological activity. Due to their favorable chemical properties and stability, they could be employed for the active receptor-mediated targeting of GRP-R positive tumors.

Bortezomib (BTZ) and Carfilzomib (CFZ) are proteasome inhibitors that represent the gold standard in the treatment of multiple myeloma. While both are very effective, they have different side effect profiles. In particular, BTZ induces peripheral neuropathy as a major side effect in a high percentage of patients, while this is only rarely observed with CFZ. In this study, we investigated possible BTZ and CFZ off-targets able to explain the difference in their neurotoxicity profiles. Off-targets were identified using SPILLO-PBSS, a software that perform a 3D in silico screening on a proteome-wide-scale. The hypothesis was biologically validated in vitro in adult mice dorsal root ganglia primary sensory neuron cultures and in a cell free model of tubulin polymerization and depolymerization. NMR binding studies were performed to demonstrate the interaction with the identified off-target. Using an innovative in silico approach, we demonstrated that tubulin is a potential off-target of BTZ. A direct BTZ-microtubules interaction could inhibit the GTPase activity of tubulin, thus reducing microtubule catastrophe and increasing tubulin polymerization. In neuron cultures, BTZ, but not CFZ, induced neurotoxicity and increased the percentage of polymerized tubulin. Moreover, in a cell-free model of tubulin polymerization and depolymerization only BTZ slowed down the depolymerization of microtubules and reduced the free phosphate concentration released during GTP hydrolysis. Lastly, NMR binding studies clearly demonstrated that only BTZ is able to directly interact with both tubulin dimers and polymerized form. In conclusion, our data for the first time gives evidence of a differential molecular mechanism of action of BTZ and CFZ that would explain their different side effect profiles: BTZ neurotoxicity is not related to its well-known proteasome inhibition, but to its ability to directly bind to tubulin, reducing microtubule catastrophe and consequently increasing the rate of