1,173 research outputs found
Synthesis and CO2 adsorption capacity of biomass waste functionalized by nanoparticles
Two composite materials were synthesized based on sodium alginate and biochar derived from licorice processing waste functionalized with silicon dioxide nanoparticles (SiO2) and iron oxide (Fe2O3), respectively, enabling the valorization of industrial waste. The adsorptive capacities of the two materials (Alg-SiO2 and BCLFe2O3) toward CO2 in the gaseous stream with nitrogen were evaluated by acid titration of carbonates present in a trap for CO2 consisting of a KOH solution placed downstream of the adsorption column. The aim of the present work is to evaluate the CO2 adsorption capacity of material functionalized by nanoparticles. AdamsâBohart, Thomas models, and % removal efficiency curves for the adsorption were examined to investigate the dynamic behavior of the column. From the tests performed in CO2 and N2 flow, the BCL-Fe2O3 material was demonstrated to have an adsorbent higher capacity than Alg-SiO2, respectively CO2 adsorbed 25 and 6 mg/g
Occurrence of Legionella spp. in thermal environments: Virulence factors and biofilm formation in isolates from a spaâ , ââ
Abstract The aim of the study was to evaluate the occurrence of Legionella spp. in the water system of a spa in the city of Naples by analyzing water, air and surface samples. On the whole, 312 samples were collected and analyzed in the course of 10 months. Legionella CYE Agar Base and Legionella Latex Test (Oxoid©) were used to identify and serotype presumptive Legionella pneumophila strains. A further identification was carried out by rDNA16S and ITS region amplification followed by a sequence analysis by DNA Sequencing Analysis software (Applied Biosystems). Similarity search was performed using BLAST algorithm against the GenBank database (NCBI GenBank). Specific in-vitro tests aimed to evaluate the production of esoenzymes (hemolysins, collagenases, mucinases, lipases, proteinases, DNAses, elastases) on GC-FC Agar were also carried out. Finally, a crystal violet staining method (absorbance at 570 nm) was used to evaluate the ability of the strains to produce biofilm in a 96-multiwell polyethylene plate. All samples were negative for L. pneumophila. Six different Legionella strains were isolated from water samples and identified as Legionella londiniensis and Legionella spp. A significant (from 1000 to 10,000 CFU/L) and a low to moderate (from 100 to 1000 CFU/L) contamination were detected respectively in the 5% and 4% of samples; 91% of water samples showed a Legionella spp. amount less than 100 CFU/L. Two Legionella londiniensis isolates showed collagenases, caseinases, proteinases and gelatinases activities, being classified as potentially pathogenic bacteria. None of the isolates were classified as strong biofilm producer but they showed a moderate to weak ability to form biofilm on polyethylene. This result is significant because large part of the spa pipelines is plastic-coated. The highest frequency of isolation of Legionella spp. was detected in the unit for Thermal Mud Therapy, which showed a relative risk value equal to 1.69 (CI 95% 0.60â4.70). Although our results proved a moderate contamination in different water samples, the presence of potentially pathogenic environmental strains of Legionella spp. should not be underestimated because most part of costumers attending the spa are old and sick people, and Legionella strains can represent a real risk
Initial pH Conditions Shape the Microbial Community Structure of Sewage Sludge in Batch Fermentations for the Improvement of Volatile Fatty Acid Production
Conversion of wastewater treatment plants into biorefineries is a sustainable alternative for obtaining valuable compounds, thus reducing pollutants and costs and protecting the environment and human health. Under specific operating conditions, microbial fermentative products of sewage sludge are volatile fatty acids (VFA) that can be precursors of polyhydroxyalkanoate thermoplastic polyesters. The role of various operating parameters in VFA production has yet to be elucidated. This study aimed to correlate the levels of VFA yields with prokaryotic microbiota structures of sewage sludge in two sets of batch fermentations with an initial pH of 8 and 10. The sewage sludge used to inoculate the batch fermentations was collected from a Sicilian WWTP located in Marineo (Italy) as a case study. Gas chromatography analysis revealed that initial pH 10 stimulated chemical oxygen demands (sCOD) and VFA yields (2020 mg COD/L) in comparison with initial pH 8. Characterization of the sewage sludge prokaryotic community structures-analyzed by next-generation sequencing of 16S rRNA gene amplicons-demonstrated that the improved yield of VFA paralleled the increased abundance of fermenting bacteria belonging to Proteobacteria, Bacteroidetes, Chloroflexi, and Firmicutes phyla and, conversely, the reduced abundance of VFA-degrading strains, such as archaeal methanogens
Whole exome sequencing in an Italian family with isolated maxillary canine agenesis and canine eruption anomalies
Objective: The aim of this study was the clinical and molecular characterization of a family segregating a trait consisting of a phenotype specifically involving the maxillary canines, including agenesis, impaction and ectopic eruption, characterized by incomplete penetrance and variable expressivity. Design: Clinical standardized assessment of 14 family members and a whole-exome sequencing (WES) of three affected subjects were performed. WES data analyses (sequence alignment, variant calling, annotation and prioritization) were carried out using an in-house implemented pipeline. Variant filtering retained coding and splice-site high quality private and rare variants. Variant prioritization was performed taking into account both the disruptive impact and the biological relevance of individual variants and genes. Sanger sequencing was performed to validate the variants of interest and to carry out segregation analysis. Results: Prioritization of variants âby functionâ allowed the identification of multiple variants contributing to the trait, including two concomitant heterozygous variants in EDARADD (c.308C>T, p.Ser103Phe) and COL5A1 (c.1588G>A, p.Gly530Ser), specifically associated with a more severe phenotype (i.e. canine agenesis). Differently, heterozygous variants in genes encoding proteins with a role in the WNT pathway were shared by subjects showing a phenotype of impacted/ectopic erupted canines. Conclusions: This study characterized the genetic contribution underlying a complex trait consisting of isolated canine anomalies in a medium-sized family, highlighting the role of WNT and EDA cell signaling pathways in tooth development
The GEANT4 toolkit capability in the hadron therapy field: simulation of a transport beam line
At Laboratori Nazionali del Sud of the Instituto Nazionale di Fisica Nucleare of Catania (Sicily, Italy), the first Italian hadron therapy facility named CATANA (Centro di AdroTerapia ed Applicazioni Nucleari Avanzate) has been realized. Inside CATANA 62 MeV proton beams, accelerated by a superconducting cyclotron, are used for the radiotherapeutic treatments of some types of ocular tumours. Therapy with hadron beams still represents a pioneer technique, and only a few centers worldwide can provide this advanced specialized cancer treatment. On the basis of the experience so far gained, and considering the future hadron-therapy facilities to be developed (Rinecker, Munich Germany, Heidelberg/GSI, Darmstadt, Germany, PSI Villigen, Switzerland, CNAO, Pavia, Italy, Centro di Adroterapia, Catania, Italy) we decided to develop a Monte Carlo application based on the GEANT4 toolkit, for the design, the realization and the optimization of a proton-therapy beam line. Another feature of our project is to provide a general tool able to study the interactions of hadrons with the human tissue and to test the analytical-based treatment planning systems actually used in the routine practice. All the typical elements of a hadron-therapy line, such as diffusers, range shifters, collimators and detectors were modelled. In particular, we simulated the Markus type ionization chamber and a Gaf Chromic film as dosimeters to reconstruct the depth (Bragg peak and Spread Out Bragg Peak) and lateral dose distributions, respectively. We validated our simulated detectors comparing the results with the experimental data available in our facility
Modulation of sewage sludge microbiota for enhancing the transition from wastewater treatment plants into biorefineries in the circular economy era
Transitioning traditional wastewater treatment plants into biorefineries offers an environmentally and economically sustainable solution. Indeed, valuable compounds can still be extracted from waste. Utilizing sewage sludge (SS) with its microbial component, materials such as volatile fatty acids (VFAs) and polyhydroxyalkanoates (PHAs) within specially designed WWTP reactors can be obtained. VFAs serve as precursors to PHAs, which provide an eco-friendly alternative to petroleum-based plastics. Understanding the impact of various operating conditions on microbial components is crucial for driving microbial metabolism toward the biosynthesis of these molecules. This innovative study, part of the European project âAchieving wider uptake of water-smart solutionsâ, focused on evaluating the effects of two operating conditionsâthe headspace volume in the fermenter and the organic loading rate (ORL) in the selective-sequence batch reactor (S-SBR)âon VFA and PHA production. The wastewater from the Palermo University campus was used to inoculate a pilot plant to simulate a real urban WWTP. Our approach is based on comparing the microbial community before and after the incubation process through metagenomic DNA extraction and 16S rDNA sequencing and on quantifying PHA and VFA yields by gas chromatography analysis. This analysis revealed that 40% of headspace volume in a 225L fermenter and an ORL of 1.3 g COD Lâ1dâ1 in S-SBR maximized VFA and PHA production. The metataxonomic analysis showed significant changes in the SS microbiota structure, promoting the growth of bacteria like Proteobacteria, Firmicutes, and Actinobacteria while reducing Verrucomicrobia. These findings enhance our understanding of bacterial modulation under various operational conditions and highlight the potential for exploiting the resources in SS within a circular economy framework
Antitumoral efficacy of the protease inhibitor gabexate mesilate in colon cancer cells harbouring KRAS, BRAF and PIK3CA mutations
The employment of anti-epidermal growth factor receptor (EGFR) antibodies
represents a backbone of the therapeutic options for the treatment of metastatic
colorectal cancer (mCRC). However, this therapy is poorly effective or ineffective in
unselected patients. Mutations in KRAS, BRAF and PIK3CA genes have recently
emerged as the best predictive factors of low/absent response to EGFR-targeted
therapy. Due to the need for efficacious treatment options for mCRC patients bearing
these mutations, in this short report we examined the antitumoral activity of the
protease inhibitor gabexate mesilate, alone and in combination with the anti-EGFR
monoclonal antibody cetuximab, in a panel of human CRC cell lines harbouring a
different expression pattern of wild-type/mutated KRAS, BRAF and PIK3CA genes.
Results obtained showed that gabexate mesilate significantly inhibited the growth,
invasive potential and tumour-induced angiogenesis in all the CRC cells employed in
this study (including those ones harbouring dual KRAS/PIK3CA or BRAF/PIK3CA
mutation), while cetuximab affected these parameters only in CRC cells with KRAS,
BRAF and PIK3CA wild-type. Notably, the antitumoral efficacy of gabexate mesilate
and cetuximab in combination was found to be not superior than that observed with
gabexate mesilate as single agent. Overall, these preliminary findings suggest that
gabexate mesilate could represent a promising therapeutic option for mCRC patients,
particularly for those harbouring KRAS, BRAF and PIK3CA mutations, either as monotherapy
or in addition to standard chemotherapy regimens. Further studies to better
elucidate gabexate mesilate mechanism of action in CRC cells are therefore
warranted
Enhancing volatile fatty acid production from sewage sludge in batch fermentation tests
Volatile fatty acids (VFA) from sewage sludge represent an excellent recovered resource from wastewater treatment. This study investigated four sludge pre-treatments (namely, potassium permanganate - KMnO4, initial pH = 10, initial pH = 2.5 and low-temperature thermal hydrolysis) by operating batch reactors under acidogenic fermentation conditions. Results revealed that 0.1 g KMnO4/g of total suspended solids represents the best pre-treatment obtaining up to 2713 mgCOD L-1 and 452 mgCOD/g of volatile suspended solids. These results also paralleled metataxonomic analysis highlighting changes in prokaryotic microbial structures of sewage sludge of the batch fermentations subjected to the different pre-treatments
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