Background: Recently, attention was drawn to a role for progranulin in the central nervous system with the identification of mutations in the progranulin gene (GRN) as an important cause of frontotemporal lobar degeneration. GRN mutations are associated with a strong reduction of circulating progranulin and widely variable clinical phenotypes: thus, the dosage of plasma progranulin is a useful tool for a quick and inexpensive large-scale screening of carriers of GRN mutations. Objective: To establish the best cutoff threshold for normal versus abnormal levels of plasma progranulin. Methods: 309 cognitively healthy controls (25–87 years of age), 72 affected and unaffected GRN+ null mutation carriers (24–86 years of age), 3 affected GRN missense mutation carriers, 342 patients with neurodegenerative diseases and 293 subjects with mild cognitive impairment were enrolled at the Memory Clinic, IRCCS S. Giovanni di Dio-Fatebenefratelli, Brescia, Italy, and at the Alzheimer Unit, Ospedale Maggiore Policlinico and IRCCS Istituto Neurologico C. Besta, Milan, Italy. Plasma progranulin levels were measured using an ELISA kit (AdipoGen Inc., Seoul, Korea). Results: Plasma progranulin did not correlate with age, gender or body mass index. We established a new plasma progranulin protein cutoff level of 61.55 ng/ml that identifies, with a specificity of 99.6% and a sensitivity of 95.8%, null mutation carriers among subjects attending to a memory clinic. Affected and unaffected GRN null mutation carriers did not differ in terms of circulating progranulin protein (p = 0.686). A significant disease anticipation was observed in GRN+ subjects with the lowest progranulin levels. Conclusion: We propose a new plasma progranulin protein cutoff level useful for clinical practice.

In addition to the main function of promoting polymerization and stabilization of microtubules, other roles are being attributed to tau, now considered a multifunctional protein. In particular, previous studies suggest that tau is involved in chromosome stability and genome protection. We performed cytogenetic analysis, including molecular karyotyping, on lymphocytes and fibroblasts from patients affected by frontotemporal lobar degeneration carrying different mutations in the microtubule-associated protein tau gene, to investigate the effects of these mutations on genome stability. Furthermore, we analyzed the response of mutated lymphoblastoid cell lines to genotoxic agents to evaluate the participation of tau to DNA repair systems. We found a significantly higher level of chromosome aberrations in mutated than in control cells. Mutated lymphocytes showed higher percentages of stable lesions, clonal and total aneuploidy (medians: 2 versus 0, p $\ll$ 0.01; 1.5 versus 0, p $\ll$ 0.01; 16.5 versus 0, p $\ll$ 0.01, respectively). Fibroblasts of patients showed higher percentages of stable lesions, structural aberrations and total aneuploidy (medians: 0 versus 0, p = 0.03; 5.8 versus 0, p = 0.02; 26.5 versus 12.6, p $\ll$ 0.01, respectively). In addition, the in depth analysis of DNA copy number variations showed a higher tendency to non-allelic homologous recombination in mutated cells. Finally, while our analysis did not support an involvement of tau in DNA repair systems, it revealed its role in stabilization of chromatin. In summary, our findings indicate a role of tau in genome and chromosome stability that can be ascribed to its function as a microtubule-associated protein as well as a protein protecting chromatin integrity through interaction with DNA.

Non-steroidal anti-inflammatory drugs (NSAIDs) can damage the small intestine, mainly through an involvement of enteric bacteria. This study examined the pathophysiology of NSAID-associated intestinal lesions in a rat model of diclofenac-enteropathy and evaluated the effect of rifaximin on small bowel damage. Enteropathy was induced in 40-week old male rats by intragastric diclofenac (4 mg/kg BID, 14 days). Rifaximin (delayed release formulation) was administered (50 mg/kg BID) 1 h before the NSAID. At the end of treatments, parameters dealing with ileal damage, inflammation, barrier integrity, microbiota composition, and TLR-NF-κB-inflammasome pathway were evaluated. In addition, the modulating effect of rifaximin on NLRP3 inflammasome was tested in an in vitro cell system. Diclofenac induced intestinal damage and inflammation, triggering an increase in tissue concentrations of tumor necrosis factor and interleukin-1β, higher expression of TLR-2 and TLR-4, MyD88, NF-κB and activation of caspase-1. In addition, the NSAID decreased ileal occludin expression and provoked a shift of bacterial phyla toward an increase in Proteobacteria and Bacteroidetes abundance. All these changes were counterbalanced by rifaximin co-administration. This drug was also capable of increasing the proportion of Lactobacilli, a genus depleted by the NSAID. In LPS-primed THP-1 cells stimulated by nigericin (a model to study the NLRP3 inflammasome), rifaximin reduced IL-1β production in a concentration-dependent fashion, this effect being associated with inhibition of the up-stream caspase-1 activation. In conclusion, diclofenac induced ileal mucosal lesions, driving inflammatory pathways and microbiota changes. In conclusion, rifaximin prevents diclofenac-induced enteropathy through both anti-bacterial and anti-inflammatory activities.

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Rapid identification of bloodstream pathogens by MALDI-TOF MS and the recently introduced rapid antimicrobial susceptibility testing (rAST) directly from positive blood cultures allow clinicians to promptly achieve a targeted therapy, especially for multidrug resistant microorganisms. In the present study, we propose a comparison between phenotypical rASTs performed in light-scattering technology (Alfred 60AST, Alifax®) and fluorescence in situ hybridization (Pheno™, Accelerate) directly from positive blood cultures, providing results in 4–7 hours. Blood samples from 67 patients admitted to the Azienda Ospedaliero-Universitaria Pisana were analyzed. After the direct MALDI-TOF MS identification, the rAST was performed at the same time both on Alfred 60AST and Pheno. Alfred 60AST provided qualitative results, interpreted in terms of clinical categories (SIR). Pheno provided identification and MIC values for each antibiotic tested. Results were compared to the broth microdilution assay (SensiTitre™, Thermo Fisher Scientific), according to EUCAST rules. Using Alfred 60AST, an agreement was reached, 91.1% for Gram-negative and 95.7% for Gram-positive bacteria, while using Pheno, the agreement was 90.6% for Gram-negative and 100% for Gram-positive bacteria. Both methods provided reliable results; Alfred 60AST combined with MALDI-TOF MS proved itself faster and cheaper. Pheno provided identification and MIC determination in a single test and, although more expensive, may be useful whenever MIC value is necessary and where MALDI-TOF MS is not present.