Preliminary evaluation of probiotic properties of Lactobacillus strains isolated from Sardinian dairy products

Twenty-three Lactobacillus strains of dairy origin were evaluated for some functional properties relevant to their use as probiotics. A preliminary subtractive screening based on the abilities to inhibit the growth of microbial pathogens and hydrolyze conjugated bile salts was applied, and six strains were selected for further characterization including survival under gastrointestinal environmental conditions, adhesion to gut epithelial tissue, enzymatic activity, and some safety properties. All selected strains maintained elevated cell numbers under conditions simulating passage through the human gastrointestinal tract, well comparable to the values obtained for the probiotic strain Lactobacillus rhamnosus GG, and were able to adhere to Caco-2 cells to various extents (from 3 to 20%). All strains exhibited high aminopeptidase, and absent or very low proteolytic and strong β-galactosidase activities; none was found to be haemolytic or to produce biogenic amines and all were susceptible to tetracycline, chloramphenicol, erythromycin, ampicillin, and amoxicillin/clavulanic acid. Our results indicate that the Lactobacillus strains analyzed could be considered appropriate probiotic candidates, due to resistance to GIT simulated conditions, antimicrobial activity, adhesion to Caco-2 cell-line, and absence of undesirable properties. They could be used as adjunct cultures for contributing to the quality and health related functional properties of dairy products

Dynamic max-consensus with local self-tuning

This work describes a novel control protocol for multi-agent systems to solve the dynamic max-consensus problem. In this problem, each agent has access to an external timevarying scalar signal and has the objective to estimate and track the maximum among all these signals by exploiting only local communications. The main strength of the proposed protocol is that it is able to self-tune its internal parameters in order to achieve an arbitrary small steady-state error without significantly affecting the convergence time. We employ the proposed protocol in the context of distributed graph parameter estimations, such as size, diameter, and radius, and provide simulations in the scenario of open multi-agent systems. Copyright (C) 2022 The Authors

Prediction of intervertebral disc mechanical response to axial load using isotropic and fiber reinforced FE models

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Long-term treatment of the developing retina with the metabotropic glutamate agonist APB induces long-term changes in the stratification of retinal ganglion cell dendrites

The gradual restriction of initially multistratified retinal ganglion cell (RGC) dendrites into ON and OFF sublaminae of the inner plexiform layer (IPL) can be effectively blocked by treating the developing retina with 2-amino-4-phosphonobutyrate (APB), the metabotropic glutamate agonist, or by light deprivation. Previous studies have focused on the short-term consequences of such manipulations, so the long-term effects of arresting dendritic stratification on the structural development of RGCs are as yet unknown. In the present study, we have addressed this issue by performing a morphological analysis of alpha RGCs labeled by retrograde transport of horseradish peroxidase injected into the dorsal lateral geniculate nucleus of adult cats that received monocular injections of APB from postnatal (P) day 2 until P30. A large proportion of the alpha cells in the APB-treated eye (44%) were found to have multistratified dendrites that terminated in both the ON and OFF sublaminae of the IPL. The dendritic arborization pattern in the sublaminae of the IPL of these cells was asymmetric, showing a variety of forms. Immunolabeling of retinal cross-sections showed that mGLUR6 receptors appeared normal in density and location, while qualitative observation suggested an increase in the axonal arborization of rod bipolar cells. These findings indicate that long-term treatment of the neonatal retina with APB induces a long- lasting structural reorganization in retinal circuitry that most likely accounts for some of the previously described changes in the functional properties of RGCs

Should we abandon the APTT for monitoring unfractionated heparin?

INTRODUCTION: The activated partial thromboplastin time (APTT) is commonly used to monitor unfractionated heparin (UFH) but may not accurately measure the amount of heparin present. The anti-Xa assay is less susceptible to confounding factors and may be a better assay for this purpose. MATERIALS AND METHODS: The validity of the APTT for monitoring UFH was assessed by comparing with an anti-Xa assay on 3543 samples from 475 patients (infants [n=165], children 1-15years [n=60] and adults [n=250]) receiving treatment dose UFH. RESULTS: Overall concordance was poor. The highest concordance (66%; 168/254) was seen in children. Concordance (51.8%) or discordance (48.4%) was almost equal in adult patients. Among adult patients whose anti-Xa level was within 0.3-0.7IU/mL, only 38% had an APTT in the therapeutic range whilst 56% were below and 6% were above therapeutic range. Children and adult patients with anti-Xa of 0.3-0.7IU/mL but sub- therapeutic APTT had significantly higher fibrinogen levels compared to those with therapeutic or supra-therapeutic APTT. CONCLUSIONS: When the anti-Xa level was 0.3-0.7IU/mL, the majority of samples from infants demonstrated a supra-therapeutic APTT, whilst adults tended to have a sub-therapeutic APTT. This may lead to under anticoagulation in infants or over anticoagulation in adults with risk of bleeding if APTT is used to monitor UFH. These results further strengthen existing evidence of the limitation of APTT in monitoring UFH. Discordance of APTT and anti-Xa level in adults and children may be due to elevation of fibrinogen level

Prevalence of Candida species in different hospital wards and their susceptibility to antifungal agents: results of a three year survey

Over a three years period, 472 Candida isolates were obtained from specimens of patients hospitalized either in ?at risk?, Bone Marrow Transplant Unit and Intensive Care Unit, or in conventional wards, Pneumological Divisions of the ?Binaghi? Hospital of Cagliari (Italy). Antifungal susceptibility profile to amphotericin B, voriconazole, fluconazole and ketoconazole was determined. Candida albicans was the predominant species while Candida krusei was the most frequent non-albicans species. C. krusei was significantly more common among Bone Marrow Transplant Unit and Intensive Care Unit than Pneumological Divisions patients (17.9% and 14.1% vs. 6.0%; p inf. 0.05). No significant differences were observed when the same distribution was analysed with regard to the other Candida species or when Bone Marrow Transplant Unit and Intensive Care Unit were compared. The profiles of susceptibility to the antifungal drugs among isolates from the different hospital wards showed no significant differences, even though most of MIC values were higher for Intensive Care Unit isolates compared to those for Bone Marrow Transplant Unit and Pneumological Divisions. For C. albicans isolates, amphotericin B was the more efficient antifungal (97.7% S), while fluconazole (6.1% R [Resistant] and 2.6% SDD [Susceptible Dose Dependent]) and ketoconazole (4.1% R and 3.2% SDD) showed the lowest activity. Voriconazole was the more efficient antimycotic for C. krusei (96.7% S) and Candida glabrata (100% S [Sensible]) isolates. This study has shown a significantly higher presence of nonalbicans Candida in at risk wards as well as a decreased susceptibility to the older azoles (ketoconazole and fluconazole) among C. albicans isolates

The MicroBioDiverSar Project: Exploring the Microbial Biodiversity in Ex Situ Collections of Sardinia

In the last decades, biodiversity preservation has gained growing attention and many strategies, laws and regulations have been enacted by governments with this purpose. The Micro-BioDiverSar (MBDS) project, the first one regarding microbiological resources, funded by the Italian Minister of Agricultural, Food and Forestry Policies (Mipaaf) through the Law 194/2015, was aimed at surveying, cataloguing, and managing the microbial resources and the related information of three Sardinian collections (Agris BNSS, Uniss, and Unica). While microorganisms were reordered and inventoried, a federated database, accessible via the web, was designed by the bioinformatician of Ospedale Policlinico San Martino of Genova, according to both international standards and laboratory needs. The resulting MBDS collection boasts a great richness of microbial resources. Indeed, over 21,000 isolates, belonging to over 200 species of bacteria, yeasts, and filamentous fungi isolated from different matrices, mainly food, of animal and vegetable origin, collected in over 50 years, were included in the database. Currently, about 2000 isolates, belonging to 150 species, are available online for both the scientific community and agri-food producers. The huge work done allowed one to know the consistency and the composition of most of the patrimony of the Sardinian microbial collections. Furthermore, the MBDS database has been proposed as a model for other Italian collections that, as the MBDS partners, are part of the Joint Research UnitMIRRI-IT Italian collections network, with the aim of overcoming fragmentation, facing sustainability challenges, and improving the quality of the management of the collections