287 research outputs found
L'evoluzione dell'approccio conservativo alla protesi totale d'anca
No full textL'approccio conservativo alla protesi totale d'anca ha come presupposto il risparmio del patrimonio osseo, specialmente nel soggetto giovane ed attivo. Vengono analizzate storia, vantaggi e svantaggi delle protesi di rivestimento e degli steli femorali a conservazione ossea (total collum, partial collum, trochanter sparing)
Optimization of a Vehicle Shape by CFD Code
No full textIn this paper fluid dynamics simulations have been executed using a CFD (Computational Fluid Dynamics) commercial code, on a Maserati Biturbo mod. 222 - 1988. At first some surfaces are optimised, choosing the more important ones for the reduction of the resistance, by a manual variation of their geometry, hence a large surface is optimised in an automatic way, by means of an own software, developed in the MatLab environment, returning the optimised surface according to a specific objective function (the resistance in this paper)
Corso di aggiornamento La displasia congenita d'anca infantile
No full textCorso di aggiornamento La displasia congenita d'anca infantile, indirizzato a medici specializzandi e specialisti in ortopedia e traumatologia e a medici specialisti in pediatria. Epidemiologia, clinica, diagnostica ecografica e radiografica, trattamento ortopedico e chirurgico della displasia d'anca infantile
IDENTIFICATION AND VALIDATION OF CRITICAL 1Q21 'ACHILLES HEEL' VULNERABILITIES OF MULTIPLE MYELOMA
No full textMultiple Myeloma (MM) is malignancy of terminally differentiated plasma cells characterized by a marked heterogeneity of genetic lesions and clinical course. Despite significant efforts towards the development of risk stratification strategies for patients with Multiple Myeloma (MM), we are still limited in our capacity to molecularly predict the natural history of these patients. Recent molecular analyses have illuminated many aspects of the pathogenesis of this heterogeneous disease, although there remains an elemental view of the compendium of genetic elements driving MM initiation and progression and how such genetic alterations functionally contribute to specific aspects of disease pathobiology, prognosis and treatment responses. Indeed, despite considerable progress in the management of MM patients, many studies have shown that some genetic alterations especially t(4;14) translocation, loss of the short arm of chromosome 17, loss of the long arm of chromosome 13 and amplification of chromosome 1q21 remain associated with a poor outcome and represent independent adverse predictors of shorter progression free survival (PFS) and overall survival (OS). The 1q21 amplicon is among the most frequent chromosomal aberrations in patients with MM (about 40% of de novo MM) and is considered a highly poor-risk genetic feature correlated with disease progression and drug resistance; it spans approximately a region of 10-15 Mb containing a large number of possible candidate genes. To date the relevant genes on 1q21 remain unclear and the absence of focal amplifications involving this region strongly suggests that more than a single candidate may represent the driver event responsible for poor outcome of this group of MM patients. Thus, the identification of critical 1q21 ‘Achilles heel’ vulnerabilities may yield a comprehensive catalog of the potential therapeutic targets for these high risk MM and provide a rationale for patient stratification. In an effort to accomplish this goal, we first identified a high-priority list of 78 copy number-driven 1q21 MM-relevant genes. Then, we have designed a high-throughput systematic shRNA screen approach in vitro to identify 1q21 genes whose loss of function results in selective death and/or growth inhibition of MM cells carrying the 1q21 amplification. After excluding shRNAs that display citotoxic activity regardless 1q21 amplification, we defined 1q21 “Achilles heel” vulnerabilities as shRNA target genes whose down-regulation decreases substantially the percentage of GFP-positive MM cells with 1q21 amplification over a time of 7 days based on a GFP-competion assay. This assay provided a list of candidate genes implicated in survival or proliferation of MM cells with 1q21 amplification; MCL1, UBAP2L, INTS3, LASS2, KRTCAP2, and ILF2. By targeting these six genes we performed secondary validation experiments in JJN3 and H929 MM cell lines, carrying 4 copies of 1q21 amplicon. The results of this secondary validation confirmed that the down-regulation of these genes caused an important decrease of proliferation and increase of apoptosis as well as growth cycle arrest. Further GEP analysis and clinical outcome studies revealed that only UBAP2L and ILF2 showed a significant prognostic value but in vivo validation studies on NOD-SCID mice identified only ILF2 correlated with in vivo survival. So our studies focused to investigate the role of ILF2 in 1q21 amplified MM.
Nuclear Factor 45 (NF45) or ILF-2 is widely expressed in normal tissue with a predominant nuclear distribution. NF45/ILF2 associates with NF90/NF110 (ILF3) interacting with DNA and RNA. ILF2 and ILF3 contribute to gene regulation at different levels, transcription, splicing, nuclear exporting, but they are also involved in other important processes like mitotic control and DNA break repair.
Down-regulation of ILF2 in MM cells with 1q21 amplification resulted in multinucleated phenotypes and abnormal nuclear morphologies that were associated with a significant accumulation of γH2AX foci and DNA damage response activation, increased sensitivity to Melphalan, DNA damaging agent, and impaired activation of DNA repair pathways. Experiments of immunoprecipitation combined with mass spectometry showed that ILF2 interacts with numerous RNA binding proteins directly implicated in DNA repair or regulation of DNA damage response by modulating alternative splicing and stability of specific pre-mRNAs. Accordingly, RNA-sequencing analysis of ILF2-depleted MM cells, when compared to cells carrying scrambled shRNAs, identified specific changes in RNA splicing patterns before and after treatment with Melphalan.
Thus, our findings have raised a new tight correlation between 1q21 amplification and DNA damage response. We identified ILF2 as a key driver of this interaction, and our findings support the development of strategies designed to modulate ILF2 expression in patients with high-risk MM carrying 1q21 amplification providing personalized therapies for patients who do not benefit from recent treatment improvements
Techniques for Thermo-Mechanical Analysis, Design and Characterization of Space Instrumentation
No full textThis doctoral thesis, “Techniques for Thermo-Mechanical Analysis, Design and Characterization of Space Instrumentation”, presents a comprehensive study of thermal control systems (TCS) for space missions, with a focus on exoplanetary exploration. The research integrates theoretical modeling, numerical simulations, and experimental validation to address critical challenges in thermal management for spacecraft payloads operating in extreme environments. The work includes the following key aspects: -Mission Design & Thermal Control : Feasibility analysis of thermal architectures for two ESA mission concepts—EXPOSURE (UV exoplanet spectroscopy) and EXODUS (NIR atmospheric escape studies)—emphasizing passive cooling, multi-layer insulation (MLI), and radiator optimization for L2 Lagrange point orbits. This part adopts an analytical approach to estimate the thermal requirements of the two missions to reach the scientific requirements supporting its feasibility. -ARIEL Mission Analysis: Thermal modeling of ESA’s Atmospheric Remote-sensing Infrared Exoplanet Large-survey (ARIEL) payload using ANSYS and ESATAN-TMS, validating cryogenic (<50 K) stability via V-groove radiators and bipod thermal isolators. This numerical analysis allowed to compare the potentialities of a simplified analysis with the finite element (FEM) and lumped parameter (TMM) approaches. Suggesting a combined use that does not compromise system-level thermal assessment reliability and that demonstrates the complementary nature of both tools, validating the potential of hybrid approaches for critical applications — while highlighting how software selection should be based on informed trade-offs between local accuracy (FEM) and global efficiency (LP), according to specific project requirements. -Material Characterization: Experimental modal analysis of Ni-P coated aluminum mirrors subjected to cryogenic conditions (77 K), quantifying Young’s modulus shifts and frequency response for ultra-stable space telescope applications. In this chapter, an experimental setup was developed for non-invasive modal analysis of the samples, along with a procedure that integrates an experimental approach with the numerical analysis and modeling to derive the material properties. The results revealed non-standard properties of the NiP coating, indicating the need for further in-depth studies on varying coating thicknesses and on manufacturing processes involving different aluminum substrate (AW 6082 T6 and RSA). -Finally, the thesis includes an application of the thermal analysis methods to a non-spatial industrial context. Experimental-computational validation of ZeriCAD injection molds with conformal cooling channels, demonstrating ±2°C thermal uniformity and 22% cycle time reduction for engineering thermoplastics (e.g. TPU) under industrial processing conditions (ISO 294-4), which would allow for better technical performance while reducing production time and costs
“Nursing management of the patient operated on for hip arthroplasty: importance of early mobilization.”
No full textreservedIntroduzione: La mobilizzazione precoce del paziente nel post-operatorio di intervento di artroprotesi d’anca è emersa come una strategia chiave per accelerare il recupero funzionale e ridurre le complicanze.
Obiettivi: Questa revisione sistematica della letteratura mira a valutare l'impatto della mobilizzazione precoce sui risultati funzionali e sulla riduzione delle complicanze nei pazienti sottoposti ad intervento di artroprotesi d'anca, sintetizzando le evidenze disponibili e identificando le aree di ricerca future.
Materiali e Metodi: È stata condotta una ricerca sistematica nelle principali banche dati biomediche (PubMed, Cochrane Library, Google Scholar) utilizzando una combinazione di termini MeSH e parole chiave pertinenti. Sono stati inclusi studi clinici randomizzati che hanno messo a confronto l'efficacia della mobilizzazione precoce con i protocolli di riabilitazione tradizionali. Sono stati estratti dati relativi alle caratteristiche dei pazienti, agli interventi, agli outcome primari (dolore, mobilità, forza muscolare) e secondari (complicanze, durata della degenza).
Risultati: La revisione ha incluso 11 studi che hanno coinvolto un totale di 14.054 pazienti. I risultati complessivi suggeriscono che la mobilizzazione precoce è associata a:
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Riduzione del dolore post-operatorio: la maggior parte degli studi ha riportato una riduzione significativa del dolore nei pazienti sottoposti a mobilizzazione precoce.
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Miglioramento della mobilità articolare: la mobilizzazione precoce ha dimostrato di accelerare il recupero della gamma di movimento articolare.
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Aumento della forza muscolare: gli studi inclusi hanno evidenziato un miglioramento della forza muscolare nei gruppi sottoposti a mobilizzazione precoce.
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Diminuzione della durata della degenza ospedaliera: la mobilizzazione precoce è risultata associata a una riduzione significativa della durata della degenza.
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Riduzione del rischio di complicanze: alcuni studi hanno riportato una riduzione del rischio di tromboembolia venosa nei pazienti sottoposti a mobilizzazione precoce, sebbene i risultati siano stati incoerenti.
Discussione: I risultati di questa revisione sistematica supportano l'efficacia della mobilizzazione precoce per migliorare i risultati funzionali e ridurre alcune complicanze nei pazienti sottoposti ad artroprotesi d'anca. Tuttavia sono emerse alcune limitazioni negli studi inclusi come la variabilità ei protocolli di mobilizzazione e dei tempi di valutazioni. Implicazioni sull’efficacia di tale metodica sono influenzate anche dal tipo di chirurgia (accesso chirurgico, tipologia di impianto protesico, perdite ematiche...) e caratteristiche del paziente. Sono necessarie ulteriori ricerche per chiarire l'impatto a lungo termine della mobilizzazione precoce e per identificare i fattori che possono predire la risposta individuale a questa strategia.
Conclusioni: La mobilizzazione precoce rappresenta una componente fondamentale della riabilitazione post-operatoria dell'artroprotesi d'anca. I risultati di questa revisione sistematica suggeriscono che questa pratica clinica dovrebbe essere fortemente raccomandata per migliorare i risultati funzionali e la qualità di vita dei pazienti.
Parole chiave: artroprotesi d'anca, mobilizzazione precoce, riabilitazione, complicanze
Three predictive scores compared in a retrospective multicenter study of nonunion tibial shaft fracture
No full textBACKGROUND Delayed union, malunion, and nonunion are serious complications in the healing of fractures. Predicting the risk of nonunion before or after surgery is challenging. AIM To compare the most prevalent predictive scores of nonunion used in clinical practice to determine the most accurate score for predicting nonunion. METHODS We collected data from patients with tibial shaft fractures undergoing surgery from January 2016 to December 2020 in three different trauma hospitals. In this retrospective multicenter study, we considered only fractures treated with intramedullary nailing. We calculated the tibia FRACTure prediction healING days (FRACTING) score, Nonunion Risk Determination score, and Leeds-Genoa Nonunion Index (LEG-NUI) score at the time of definitive fixation. RESULTS Of the 130 patients enrolled, 89 (68.4%) healed within 9 months and were classified as union. The remaining patients (n = 41, 31.5%) healed after more than 9 months or underwent other surgical procedures and were classified as nonunion. After calculation of the three scores, LEG-NUI and FRACTING were the most accurate at predicting healing. CONCLUSION LEG-NUI and FRACTING showed the best performances by accurately predicting union and nonunion
Infiltrazioni intra-articolari ecoguidate di acido ialuronico (Hyalubrix) nel trattamento di pazienti con grave osteoatrosi d'anca: dati clinici e valutazioni preliminari
No full textL'osteoartrosi dell'anca (AO), nei casi indirizzabili al trattamento chirurgico è solitamente curata con terapie mediche sistemiche. la viscosupplementazione si propone come opzione terapeutica. il presente studio ha mostrato efficacia nel trattamento di pazienti con OA d'anca di grado alto
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