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Ultra-hypofractionated stereotactic radiotherapy for prostate cancer in 5 fractions: current evidences and our clinical experience
No full textAIMS: The present is a retrospective evaluation of acute genito-urinary (GU) and gastro-intestinal (GI) toxicity, in addition to biochemical recurrence rate in 57 prostate cancer patients treated at our Institution with ultra-hypofractionated RT (UHRT) schedule.
METHODS: From January 2021 to December 2022 we have treated 57 patients with prostate cancer, using an UHRT scheme of 5-fractions every other day for a total dose delivered of 36.25 Gy, according to the PACE-B trial treatment schedule. Good urinary function, assessed by International Prostate Symptom Score (IPSS), were required. The simulation CT scans were acquired in supine position and fused with MRI for CTVs definition for every patient. Each treatment was performed by Accuray's TomoTherapy with daily IGRT. The evaluation of the set-up was very restrictive before daily treatment delivery.
RESULTS: According to RTOG toxicity scale, the acute GU toxicity at 3 months from RT, GU toxicity was G0 for 30 patients (52.6%), G1 for 26 (45.6%) and G2 for one only (1.75%); rectal toxicity was G0 for 56 patients (98.25%) and G1 for one only (1.75%). The median follow-up (FU) was 9 months (2-24 months). In the following FU months, we observed progressively lower urinary and rectal toxicity, except for one patient who showed G2 GU toxicity at 12 months. All but one patient had a progressive PSA value decrease.
CONCLUSIONS: In our experience, UHRT appears to be safe and well tolerated even without the use of rectal spacer devices. A longer FU is necessary to evaluate late toxicity and disease control rate
Investigation on the role of polymeric ligands in heterogeneous nanocatalysis towards the development of hybrid metal-polymer catalysts
No full textThe relationship between catalytic properties and the nature of the active phase is well-established, with increased presence typically leading to enhanced catalysis. However, the costs associated with acquiring and processing these metals can become economically and environmentally unsustainable for global industries. Thus, there is potential for a paradigm shift towards utilizing polymeric ligands or other polymeric systems to modulate and enhance catalytic performance. This alternative approach has the potential to reduce the requisite amount of active phase while preserving effective catalytic activity. Such a strategy could yield substantial benefits from both economic and environmental perspectives. The primary objective of this research is to examine the influence of polymeric hydro-soluble ligands on the final properties, such as size and dispersion of the active phase, as well as the catalytic activity, encompassing conversion, selectivity towards desired products, and stability, of colloidal gold nanoparticles supported on active carbon. The goal is to elucidate the impact of polymers systematically, offering a toolbox for fine-tuning catalytic performances from the initial stages of catalyst design. Moreover, investigating the potential to augment conversion and selectivity in specific reactions through tailored polymeric ligands holds promise for reshaping catalyst preparation methodologies, thereby fostering the development of more economically sustainable materials
Optically, chemically and electrically active (supra)molecular systems: from solution to liposomes and protein nanopores
No full textThis thesis deals with the characterization of stimuli-responsive molecular and supramolecular systems in different environments, including biomimetic settings such as liposomes and protein nanopores.
A substantial portion of the work centers on the investigation of the recently introduced photochromic compound Donor-Acceptor Stenhouse adduct (DASA). Chapter 2 delves into their fundamental photochemical properties and isomerization behavior in organic solution. Their response to both optical and chemical stimulation, probed through photophysical and photochemical techniques, reveals an intriguing multiresponsive behavior.
Chapter 3 details parallel studies on the preparation and characterization of liposomal vesicles doped with DASAs, aiming at obtaining an optically active system for potential applications in controlled drug delivery. As it will be shown, the pronounced polarity contrast between DASAs isomeric forms enables the incorporation of DASA into the liposomal membrane and subsequent release of the molecule into the aqueous compartment upon visible light irradiation.
Chapter 4 delves into the electrophysiological studies conducted on a transmembrane protein nanopore, α-hemolysin. Two approaches to influence by external stimulus the current flowing through the protein are presented. The first involves a novel bioconjugation strategy developed using reactions inspired by DASA synthetic preparation, while the second approach introduces the macrocycle cucurbituril within the pore, acting as a molecular adapter. This study thus represents an advance in understanding modification strategies of biomimetic ion channels.
On a separated research line, in Chapter 5 is presented the characterization of supramolecular host-guest complexes formed in organic solution between calixarene macrocycle/capsule hosts and bipyridinium guests using photophysical techniques. Calixarene-based structures functionalized with urea receptors emerge as excellent heteroditopic hosts, as it will be shown through the thermodynamic and kinetic analysis of their complexes.
Overall, these projects collectively contribute to advancing the understanding of the supramolecular chemistry of these systems and pave the way for future studies in this intriguing field
Dual investigation of Myeloid and Lymphoid compartments: role of miRNAs in MDS and HOXA9 in B-ALL
No full textHere we report an exploration of uncommonly investigated molecules in these diseases, microRNA in MDS, and HoxA9 in B-ALL.
miRNAs are small non-coding RNAs that regulate gene expression and are linked to cancer development and progression. MDS with an increased risk of AML progression are managed using hypomethylating agents(azacytidine), alone or in conjunction with other drugs. miRNA expression of 26 high-risk MDS-patients treated with azacytidine and lenalidomide, at baseline and during therapy, were analyzed. miR-192-5p was discovered as differentially expressed during therapy response. Patients were clustered in responder, non-responder, and early losing-response and showed a different expression of this miRNA, as well as of its target BCL2. This investigation also revealed a significant association between miR-192-5p levels during the therapy and extended Overall Survival (OS) and Leukemia-Free Survival (LFS) in responder patients.
On the ALL side, HoxA9 is a member of the Hox-gene family. Dysregulated expression of HoxA9 has been associated with leukemia, where is commonly upregulated. A recent publication revealed a significant downregulation of HoxA9 mRNA levels in leukemic murine samples when compared with normal B-cell precursors. This was highly surprising, because HoxA9 is an oncogene involved in AML, T-ALL, and B-ALL with MLL rearrangement, and led to speculate on tumor suppressive role of this gene in IL7R mutant B-ALL. Proliferation on human cell lines was then assessed and the result was a proliferative disadvantage associated with HoxA9 overexpression. The downregulation mechanism was then investigated, evaluating on mice-derived leukemic cells the effect of SAHA.
The aim of this dual investigation of miRNA in MDS and HoxA9 in B-ALL is to increase the understanding of the intricate web of molecular events that drive these hematological malignancies, ultimately striving for improved patient management and outcome
Microwave spectroscopy in the gas and solid phases: from rotational spectroscopy on organic molecules to the development of inorganic quantum sensors.
No full textThis thesis deals with two applications of microwave spectroscopy: rotational spectroscopy and quantum sensing.
The first part reports the recording and analysis of rotational spectra under supersonic expansion conditions for two distinct molecular sets. The first set includes 2'-, 3'-, and 4'-aminoacetophenone (2AA, 3AA, and 4AA respectively), while the second set comprises N,N-diethylhydroxylamine (DEHA) and N,N-diethylacetoxylamine (DEAA). The formation of 1:1 weakly bound molecular complexes with water or neon has also been observed, allowing for the spectrum assignment of 2AA:W, 2AA:Ne, and DEHA:W. All these species exhibit complex spectra with hyperfine structures due to the presence of 14N and/or the effects of internal methyl rotation. Several isotopologues at natural abundance have been identified for a total of 39 species analysed. These structures have been interpreted using quantum mechanical models, allowing the determination of nuclear quadrupole coupling constants and methyl rotational barriers. A complementary experimental approach has been used, including Fourier transform microwave spectroscopy, free jet millimeter absorption wave spectroscopy and chirped pulse Fourier transform microwave spectroscopy.
Moreover, DEHA has been investigated through photoelectron spectroscopy, which unveils structural rearrangements upon ionization and effects of dissociation in ethylamine and water. The derived spectroscopic constants enable future investigations in various frequency regions and molecular detection applications in analytical and astrochemical fields.
Transitioning to condensed matter physics, microwave spectroscopy is employed to coherently manipulate and control the spin state of VB- defects in hexagonal Boron Nitride. Significant extension of coherence times through dynamical decoupling protocols (CPMG, XY8-N, and Spinlock) and the potential use of VB- as an RF field sensor are demonstrated. This enhanced spin control opens up possibilities for nanoscale spin sensing in low-dimensional quantum materials and devices
High-strength steels manufactured via Laser Powder Bed Fusion: effect of post-process heat treatments and surface finishing on microstructure and mechanical properties
No full textLaser Powder Bed Fusion (LPBF) permits the manufacturing of parts with optimized geometry, enabling lightweight design of mechanical components in aerospace and automotive and the production of tools with conformal cooling channels. In order to produce parts with high strength-to-weight ratio, high-strength steels are required. To date, the most diffused high-strength steels for LPBF are hot-work tool steels, maraging and precipitation-hardening stainless steels, featuring different composition, feasibility and properties. Moreover, LPBF parts usually require a proper heat treatment and surface finishing, to develop the desired properties and reduce the high roughness resulting from LPBF. The present PhD thesis investigates the effect of different heat treatments and surface finishing on the microstructure and mechanical properties of a hot-work tool steel and a precipitation-hardening stainless steel manufactured via LPBF. The bibliographic section focuses on the main aspects of LPBF, hot-work tool steels and precipitation-hardening stainless steels. The experimental section is divided in two parts. Part A addresses the effect of different heat treatments and surface finishing on the microstructure, hardness, tensile and fatigue behaviour of a LPBF manufactured hot-work tool steel, to evaluate its feasibility for automotive and racing components. Results indicated the possibility to achieve high hardness and strength, comparable to the conventionally produced steel, but a great sensitivity of fatigue strength on defects and surface roughness resulting from LPBF. Part B investigates the effect of different heat treatments on the microstructure, hardness, tensile and notch-impact behaviour of a LPBF produced precipitation-hardening stainless steel, to assess its feasibility for tooling applications. Results indicated the possibility to achieve high hardness and strength also through a simple Direct Aging, enabling heat treatment simplification by exploiting the microstructural features resulting from LPBF
The predictive role of the human gut microbiota in covid-19: implications for disease severity and post-covid syndrome
No full textThe COVID-19 pandemic, sparked by the SARS-CoV-2 virus, stirred global comparisons to historical pandemics. Initially presenting a high mortality rate, it later stabilized globally at around 0.5-3%. Patients manifest a spectrum of symptoms, necessitating efficient triaging for appropriate treatment strategies, ranging from symptomatic relief to antivirals or monoclonal antibodies.
Beyond traditional approaches, emerging research suggests a potential link between COVID-19 severity and alterations in gut microbiota composition, impacting inflammatory responses. However, most studies focus on severe hospitalized cases without standardized criteria for severity. Addressing this gap, the first study in this thesis spans diverse COVID-19 severity levels, utilizing 16S rRNA amplicon sequencing on fecal samples from 315 subjects. The findings highlight significant microbiota differences correlated with severity. Machine learning classifiers, including a multi-layer convoluted neural network, demonstrated the potential of microbiota compositional data to predict patient severity, achieving an 84.2% mean balanced accuracy starting one week post-symptom onset. These preliminary results underscore the gut microbiota's potential as a biomarker in clinical decision-making for COVID-19.
The second study delves into mild COVID-19 cases, exploring their implications for ‘long COVID’ or Post-Acute COVID-19 Syndrome (PACS). Employing longitudinal analysis, the study unveils dynamic shifts in microbial composition during the acute phase, akin to severe cases. Innovative techniques, including network approaches and spline-based longitudinal analysis, were deployed to assess microbiota dynamics and potential associations with PACS. The research suggests that even in mild cases, similar mechanisms to hospitalized patients are established regarding changes in intestinal microbiota during the acute phase of the infection. These findings lay the foundation for potential microbiota-targeted therapies to mitigate inflammation, potentially preventing long COVID symptoms in the broader population. In essence, these studies offer valuable insights into the intricate relationships between COVID-19 severity, gut microbiota, and the potential for innovative clinical applications
Rhodium clusters: investigation of the reactivity towaeds phosphines and selected d- and p-metals
No full textDuring my PhD we focused on different research projects concerning the synthesis and characterization of new rhodium carbonyl clusters. More specifically, we studied the reactivity between Rh4(CO)12 and different bidentate phosphines, obtaining seven different species: Rh4(CO)10(dppe), Rh4(CO)8(dppe)2, Rh4(CO)10(dppf), {Rh4(CO)10(dpp-hexane)}2, {Rh4(CO)10(t-dppe)}2, Rh2(CO)2(dppf)2 and Rh4(CO)9(μ2-dppe)(μ1-dppeO).
The reactivity of [Rh7(CO)16]3- with [AuCl4]- and Au(Et2S)Cl led to the formation of seven bimetallic clusters, of which four new ones, namely [Rh16Au6(CO)36]6-, [Rh10Au(CO)26]3-, [Rh16Au6(CO)36]4-, [Rh16Au6(CO)36]5-, [Rh22Au3(CO)47]5-, [Rh19Au5(CO)40]4- and [Rh20Au7(CO)45]5-. The reactivity of [Rh16Au6(CO)36]6- and [Rh10Au(CO)26]3- was studied as well.
The reactivity of [Rh7(CO)16]3- with AgBF4, AgNO3 and with Pt(Et2S)2Cl2 was investigated, yielding only to the already known [Rh6N(CO)15]-, [PtRh5(CO)15]- and [PtRh4(CO)14]2- compounds.
[Rh7(CO)16]3- war reacted with SnCl2·2H2O in acetone obtaining [Rh7Sn4Cl10(CO)14]5-, and [Rh12Sn(CO)23Cl2]4- was reacted with H+ obtaining [Rh18Sn3Cl2(CO)44]4-.
Reactivity of [Rh7(CO)16]3- with InCl3 resulted in the isolation of [Rh12In(CO)28]3- and [Rh11In3(CO)25Cl2]3-, already known in our research lab, and the new [HRh11In(CO)26]3-. Moreover, a more straightforward synthesis for [Rh6InCl3(CO)15]2- was found, and this also led to the isolation of the [Rh6InCl2(DMF)(CO)15]-.
The recover or rhodium as valuable carbonyl compound was also studied, and starting from a mixture of by-products it was possible to obtain the starting material [Rh7(CO)16]3-
Advanced imaging study in cerebrovascular pathology for the personalization of therapy: from the capillary microcirculation to the vessel wall
No full textObjectives: To investigate the use of intravascular optical coherence tomography (IVOCT) for carotid artery stenting (CAS) procedures in patients with atherosclerotic stenosis. Examine possible markers that might identify the onset of new cerebral ischemic lesions on MRI. Specifically, attention was drawn to the morphological features of the used dual layer stent, which could be underestimated during traditional CAS procedures. Secondary goals are to compare the safety and efficacy of different CAS techniques and the accuracy of the vessel analysis software’s on pre-operative CTA examination used to quantify ICA stenosis with the gold standard IVOCT.
Material and Methods: Ten patients underwent CAS procedure with flow-arrest technique and IVOCT evaluations prior to and following stent deployment, while five matched patients underwent CAS procedure with distal embolic protection device (EPD) technique. All patients underwent 24-hours 3T MRI examination to check for ischemic lesions; all patients were treated with the same dual-layer stent.
Results: Patients with new ischemic lesions demonstrated peculiar stent configuration in the distal end, and a strong Spearman’s rank order correlation was found among the volume of new DWI lesions and the stent configuration in its distal end (Rs: 0.81; p <0.001). No statistically significant differences were observed in the total burden of new ischemic lesions for each technique. The vessel analysis software's on CTA comparison demonstrated a higher diagnostic accuracy in the degree of ICA stenosis compared to the gold standard of IVOCT of the specialized software (ROC curve = 0.63; p = 0.06) compared to the general software (ROC curve = 0.57, p = 0.31).
Conclusions: Study’s results support the use of IVOCT to allow recognition of potential features that can predict the onset of new cerebral ischemic lesions. Additionally, IVOCT made it possible to evaluate specialized software's increased accuracy in the pre-operative evaluation of ICA atherosclerotic stenosis
Toward wellbeing: investigation of traditional, classical and innovative approaches to improve population and environmental health
No full textAs the word population continues to grow and global resources are limited, the WHO definition of health is difficult to achieve for a large part of the population. Humanity is facing the need to improve both environmental and human wellbeing. This can be done through careful planning and management of natural resources, ensuring food safety and reducing and converting wastes.
This work aims to contribute to the improvement of population and environmental health exploring different research fields: urban park ecosystem services, food chemical risk assessment and agri-food by-product valorization.
To highlight the importance of urban parks and their ecosystem services, an ethnobotanical study was carried out in the Ausa urban park in Rimini, using a citizen science approach. The results showed that Ausa Park is an important focal point for plant gatherers in Rimini, as it allows for plant foraging and contributes to preserve the knowledge of the use of plants.
Two food safety studies were carried out, looking at the exposure of Poles to bisphenol A through the consumption of soft drinks and to cadmium through the consumption of chocolate bars. The results, compared with EFSA’s scientific opinion, show that the exposure of the Polish population to BPA is of health concern, while cadmium is not.
In the agri-food by-product valorization, a green extraction method was optimized to recover valuable phenolic compounds from red-fleshed apple pomace; moreover, the possibility of recovering pectin from the residue was evaluated. Furthermore, valuable compounds in four different types of wheat milling by-products, considered as an alternative source of bioactive compounds with potential human health benefits, were investigated.
In conclusion, this work produced usable data in urban green area management and planning, in food chemical risk assessment and in business production decisions, thus contributing to improving environmental and people wellbeing