9 research outputs found
Ottimizzazione di mix design di geopolimeri a base di metacaolino e studio dei relativi processi di formatura
Il seguente lavoro di tesi si pone come obiettivo di ottimizzare il mix design di materiali geopolimerici a base di metacaolino in modo da ottimizzare il procedimento di formatura tramite pressatura tipico delle piastrelle ceramiche.
La parte iniziale del lavoro sperimentale è stata incentrata sullo studio dell’ottimizzazione delle formulazioni per ottenere impasti geopolimerici a base di metacaolino idonei per la pressatura e il colaggio; sono stati quindi preparate diverse formulazioni ottenute variando diversi parametri di processo, quali il contenuto totale di acqua dell’impasto e la concentrazione di quarzo utilizzato come filler inerte.
Su tali mix è stato individuato il processo di formatura più idoneo dal punto di vista di temperatura di consolidamento, modalità e tempi di cottura ed è stato messo a punto il procedimento ottimale per la preparazione dei materiali, procedimento che è stato poi mantenuto per l’intero decorso dello studio. Nella produzione degli impasti si è deciso di eliminare sistematicamente quelle formulazioni che avevano prodotto materiali con peggiori prestazioni fisiche, come alcune formulazioni testate per il colaggio.
Successivamente, dopo avere preparato i campioni, su di essi sono state eseguite le prove di assorbimento d’acqua e porosimetria ad intrusione di mercurio, per valutare le caratteristiche fisiche dei vari impasti prodotti, osservazioni al microscopio ottico e al microscopio a scansione elettronica, per analizzare i campioni selezionati dal punto di vista microstrutturale e morfologico e prove al microscopio riscaldante, per studiarne il comportamento alle alte temperature.
I risultati ottenuti sono stati messi a confronto con quelli dei materiali ceramici tradizionali, per avere indicazioni sulla potenzialitĂ dei prodotti a base geopolimerica come alternativa alla produzione di piastrelle ceramiche
Work-related eye injuries: A relevant health problem. main epidemiological data from a highly-industrialized area of northern Italy
The province of Modena is one of the most industrialized areas of Northern Italy. The medical records of the Ophthalmological Emergency Department (OED) of Modena University Hospital were studied: there were 13, 470 OED accesses in 2014 and in 754 cases that an occupational eye injury occurred. The frequency of work-related eye injuries (3â°) was lower compared to other published studies, but the absolute number is still relevant, showing the need for more adequate prevention, especially in metal work, construction work, and agriculture, where the worst prognoses were observed. Intervention programs must be implemented as early as possible in the working life, considering that the frequency in younger workers is about double that of the oldest age class (3.5â°vs. 1.8â°), and special attention should also be given to foreigners, who have a 50% higher injury risk. Furthermore, the planning of specific interventions for eye-injured workers may be useful, considering that a previous injury does not appear to encourage the adoption of preventive interventions, and a subgroup of eye-injured workers have a potential risk for new injuries. Finally, the data presented here indicates how OED records, integrated with specific occupational information, can be applied for studies on work-related eye injuries
Intraspecies characterization of bacteria via evolutionary modeling of protein domains
The ability to detect and characterize bacteria within a biological sample is crucial for the monitoring of infections and epidemics, as well as for the study of human health and its relationship with commensal microorganisms. To this aim, a commonly used technique is the 16S rRNA gene targeted sequencing. PCR-amplified 16S sequences derived from the sample of interest are usually clustered into the so-called Operational Taxonomic Units (OTUs) based on pairwise similarities. Then, representative OTU sequences are compared with reference (human-made) databases to derive their phylogeny and taxonomic classification. Here, we propose a new reference-free approach to define the phylogenetic distance between bacteria based on protein domains, which are the evolving units of proteins. We extract the protein domain profiles of 3368 bacterial genomes and we use an ecological approach to model their Relative Species Abundance distribution. Based on the model parameters, we then derive a new measurement of phylogenetic distance. Finally, we show that such model-based distance is capable of detecting differences between bacteria in cases in which the 16S rRNA-based method fails, providing a possibly complementary approach , which is particularly promising for the analysis of bacterial populations measured by shotgun sequencing
Automated Prediction of the Response to Neoadjuvant Chemoradiotherapy in Patients Affected by Rectal Cancer
Simple Summary Colorectal cancer is the second most malignant tumor per number of deaths after lung cancer and the third per number of new cases after breast and lung cancer. The correct and rapid identification (i.e., segmentation of the cancer regions) is a fundamental task for correct patient diagnosis. In this study, we propose a novel automated pipeline for the segmentation of MRI scans of patients with LARC in order to predict the response to nCRT using radiomic features. This study involved the retrospective analysis of T-2-weighted MRI scans of 43 patients affected by LARC. The segmentation of tumor areas was on par or better than the state-of-the-art results, but required smaller sample sizes. The analysis of radiomic features allowed us to predict the TRG score, which agreed with the state-of-the-art results. Background: Rectal cancer is a malignant neoplasm of the large intestine resulting from the uncontrolled proliferation of the rectal tract. Predicting the pathologic response of neoadjuvant chemoradiotherapy at an MRI primary staging scan in patients affected by locally advanced rectal cancer (LARC) could lead to significant improvement in the survival and quality of life of the patients. In this study, the possibility of automatizing this estimation from a primary staging MRI scan, using a fully automated artificial intelligence-based model for the segmentation and consequent characterization of the tumor areas using radiomic features was evaluated. The TRG score was used to evaluate the clinical outcome. Methods: Forty-three patients under treatment in the IRCCS Sant'Orsola-Malpighi Polyclinic were retrospectively selected for the study; a U-Net model was trained for the automated segmentation of the tumor areas; the radiomic features were collected and used to predict the tumor regression grade (TRG) score. Results: The segmentation of tumor areas outperformed the state-of-the-art results in terms of the Dice score coefficient or was comparable to them but with the advantage of considering mucinous cases. Analysis of the radiomic features extracted from the lesion areas allowed us to predict the TRG score, with the results agreeing with the state-of-the-art results. Conclusions: The results obtained regarding TRG prediction using the proposed fully automated pipeline prove its possible usage as a viable decision support system for radiologists in clinical practice
Analysis of BTA6 in Bruna Italiana and Pezzata Rossa cattle assayed with 2,535 SNPs
A high density SNP marker panel (54,000 SNPs) was used to investigate the genome of 775 Bruna
Italiana and 493 Pezzata Rossa bulls. Observed and expected heterozygosities were calculated overall
and per chromosome. In both breeds, values were not significantly different. Bos taurus Chromosome
6 (BTA6), carrying the casein loci, was analysed in higher detail. Overall, 2,535 markers were assayed
on this chromosome. After discarding monomorphic markers, those having more than 10 missing values,
and those having minor allele frequency below 2%, 1,814 and 2,061 SNPs were retained in Bruna
Italiana and Pezzata Rossa, respectively. To detect signatures of ancient and recent selection, we
calculated FIS inbreeding coefficient values of all BTA6 polymorphic markers, within sliding windows
of groups of 5 adjacent SNPs and within 122 adjacent regions spanning 1 Mb intervals. These preliminary
analyses indicated that genotyping of several thousand SNPs potentially allows the detection of
the footprint of selection dodging the confounding effects of the population demographic history (i.e.,
effective population size, genetic structure, and mating pattern). A wider understanding of how and
where selection shaped patterns of genetic variation along the genome may provide important insights
into the dynamics of evolutionary change, facilitating both the identification of functionally significant
genomic regions and genotype-phenotype correlations. Outlining such regions could allow focusing
the fine mapping strategy to identify candidate genes and causative mutations affecting important
economic or adaptive traits
Micelle polimeriche stabilizzate con polidopamina e loro interazione con acido folico
In questo lavoro di tesi è stato sintetizzato un copolimero a blocchi con proprietà anfifiliche per un loro utilizzo nel campo del drug delivery. Si è partiti dalla sintesi di poli (glicidil metacrilato) mediante tecnica RAFT (Reversible Addition-Fragmentation chain Transfer), con il fine di ottenere un polimero con una distribuzione del peso molecolare ben definita. Il trattamento del polimero con un opportuno nucleofilo fornisce un materiale con caratteristiche differenti da quelle di partenza, con l’ottenimento di un polimero solubile in acqua in grado di autoassemblarsi, con formazione di micelle. Quest’ultime sono state sottoposte a trattamenti per aumentarne la stabilità fisica mediante reticolazione di polidopamina sulla superficie esterna della micella. Inoltre, nell'ottica di migliorare l’inglobamento delle micelle all'interno di cellule target, si è deciso di effettuare una funzionalizzazione del guscio esterno con acido folico. Infine, le micelle sono state marcate con un cromoforo fluorescente che ha permesso di poter verificare e comparare l’inglobamento delle micelle all'interno delle cellule attraverso microscopia confocale
Beyond pain: can antidepressants improve depressive symptoms and quality of life in patients with neuropathic pain? A systematic review and meta-analysis
Neuropathic pain can be a predictor of severe emotional distress, up to full blown depressive states. In these patients, it is important to move beyond the sole treatment of pain, in order to recognize depressive symptoms, and to ultimately improve the quality of life.We systematically searched for published and unpublished clinical trials assessing the efficacy and tolerability of antidepressants versus placebo on depression, anxiety and quality of life in patients with neuropathic pain, and pooled data in a meta-analysis.A total of 37 studies fulfilled eligibility criteria and 32 provided data for meta-analysis. Antidepressants were more effective than placebo in improving depressive symptoms (standardized mean difference -0.11; 95% confidence interval -0.20 to -0.02), although the magnitude of effect was small, with a number-needed-to-treat of 24. No significant difference emerged between antidepressants and placebo in reducing anxiety. Quality of life appeared improved in patients on antidepressants, as did pain. Acceptability and tolerability were higher in patients on placebo.To our knowledge, this is the first meta-analysis specifically focusing on the effect of antidepressants on psychiatric symptoms and quality of life in patients with neuropathic pain. Our findings suggest that, despite their potential benefit in patients with neuropathic pain, antidepressants should be prescribed with particular care, as they might be less tolerable in such a fragile population. However, our findings warrant further research to explore how a correct use of antidepressants can help patients to cope with the consequences of neuropathic pain on their psychosocial health and quality of life
Human chorionic gonadotropin stimulation gives evidence of differences in testicular steroidogenesis in Klinefelter syndrome, as assessed by liquid chromatography-tandem mass spectrometry
BACKGROUND:
Men with Klinefelter syndrome (KS) show hypergonadotropic hypogonadism, but the pathogenesis of hypotestosteronemia remains unclear. Testicular steroidogenesis in KS men was evaluated over three decades ago after human chorionic gonadotropin (hCG) stimulation, but inconclusive results were obtained. Intriguingly, some recent studies show increased intratesticular testosterone concentrations in men with KS.
OBJECTIVE:
To analyze serum steroid profile, as a proxy of testicular steroidogenesis, after hCG stimulation in KS compared with control men.
DESIGN:
A prospective, longitudinal, case-control, clinical trial.
METHODS:
Thirteen KS patients (36±9 years) not receiving testosterone (TS) replacement therapy and 12 eugonadic controls (32±8 years) were enrolled. Serum steroids were measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS) at baseline and for five consecutive days after intramuscular injection of 5000IU hCG.
RESULTS:
Progesterone (P), 17-hydroxyprogesterone (17OHP), TS, and estradiol (E2) showed a significant increase (P<0.001) after hCG stimulation in both groups. On the contrary, androstenedione (AS) and dehydroepiandrosterone did not increase after hCG stimulation. The 17OHP/P ratio increased in both groups (P<0.001), the TS/AS ratio (17β-hydroxysteroid dehydrogenase type 3 (17βHSD3) activity) did not increase after hCG in any group, and the E2/TS ratio (aromatase activity) increased significantly in both groups (P=0.009 in KS and P<0.001 in controls). Luteinizing hormone decreased after hCG in both groups (P=0.014 in KS and P<0.001 in controls), whereas follicle-stimulating hormone decreased only in control men (P<0.001).
CONCLUSION:
This study demonstrates for the first time using LC-MS/MS that Leydig cells of KS men are able to respond to hCG stimulation and that the first steps of steroidogenesis are fully functional. However, the TS production in KS men is impaired, possibly related to reduced hydroxysteroid deydrogenase activity due to an unfavorable intratesticular metabolic state