Inflating Fat Bubbles in Clusters of Galaxies by Wide Jets

We conduct two-dimensional hydrodynamical simulations of jets expanding in the intra-cluster medium (ICM). We find that for a fat, i.e. more or less spherical, bubble attached to the center to be formed the jet should have high momentum flux and a large opening angle. Typically, the half opening angle should be >50 degrees, and the large momentum flux requires a jet speed of \~10,000 km/sec. The inflation process involves vortices and local instabilities which mix some ICM with the hot bubble. These results predict that most of the gas inside the bubble has a temperature of 3x10^8<T<3x10^9 K, and that large quantities of the cooling gas in cooling flow clusters are expelled back to the intra-cluster medium, and heated up. The magnetic fields and relativistic electrons that produce the synchrotron radio emission might be formed in the shock wave of the jet.Comment: Submitted to ApJ Letter

Effect of Unloading Condition on the Healing Process and Effectiveness of Platelet Rich Plasma as a Countermeasure: Study on In Vivo and In Vitro Wound Healing Models

Wound healing is a very complex process that allows organisms to survive injuries. It is strictly regulated by a number of biochemical and physical factors, mechanical forces included. Studying wound healing in space is interesting for two main reasons: (i) defining tools, procedures, and protocols to manage serious wounds and burns eventually occurring in future long-lasting space exploration missions, without the possibility of timely medical evacuation to Earth; (ii) understanding the role of gravity and mechanical factors in the healing process and scarring, thus contributing to unravelling the mechanisms underlying the switching between perfect regeneration and imperfect repair with scarring. In the study presented here, a new in vivo sutured wound healing model in the leech (Hirudo medicinalis) has been used to evaluate the effect of unloading conditions on the healing process and the effectiveness of platelet rich plasma (PRP) as a countermeasure. The results reveal that microgravity caused a healing delay and structural alterations in the repair tissue, which were prevented by PRP treatment. Moreover, investigating the effects of microgravity and PRP on an in vitro wound healing model, it was found that PRP is able to counteract the microgravity-induced impairment in fibroblast migration to the wound site. This could be one of the mechanisms underlying the effectiveness of PRP in preventing healing impairment in unloading conditions

Le malattie del sistema nervoso centrale, periferico e della muscolatura scheletrica

Questo libro è nato con l'intento principale di ottemperare alle esigenze didattiche degli studenti della Facoltà di Farmacia, nell'ambito delle Scienze Mediche. Infatti, nel volume vengono trattati, oltre ai tradizionali argomenti di Patologia Generale, anche i principali temi di Fisiopatologia degli organi e degli apparati al fine di permettere allo studente una migliore comprensione del meccanismo d'azione e dell'uso clinico dei farmaci e di fornire le basi per un proficuo colloquio con il medico. Il libro è naturalmente rivolto anche a tutti coloro che operano nell'ambito sanitario o scientifico, desiderosi di avere una visione d'insieme aggiornata e ragionata delle principali malattie che colpiscono l'uomo, analizzate soprattutto in termini di meccanismi fisiopatologici di base. Scopo del libro non è, quindi, quello di offrire i mezzi per fare una diagnosi clinica, ma quello di fornire una migliore conoscenza dell'ambito in cui deve svolgersi l'intervento assistenziale

Cementless Primary Total Hip Arthroplasty with a Trabecular Titanium Implant: Results at Short-to-Medium-Term Follow-Up

Over the last two decades, cementless hip prostheses gained increasing popularity. Highly porous, trabecular coatings and their promising bone-friendly properties also came to a wider diffusion. As a consequence, this study was aimed to evaluate clinical and radiographic results at short-to-medium term of cementless prosthetic implants with trabecular titanium cup and titanium femoral metaphyseal stem highly porous coatings. From September 2012 to June 2015 213, cementless total hip arthroplasties were performed in 200 patients. All patients received a cementless Accolade II stem and Tritanium cup with UHMWPE Trident X3 Bearing Technology polyethylene liner. All surgeries were performed using a tissue-sparing modified posterolateral approach. All patients underwent prophylaxis for heterotopic ossifications. For every patient, the following data were collected: age, gender, height, weight, body mass index, blood loss, preoperative and postoperative hemoglobin, surgical time, and complications. Harris Hip Score was obtained for every patient. Radiographic measurements were performed using a freeware software (TraumaCAD 2.0). The computed parameters were inclination and anteversion of acetabular cup and presence of heterotopic ossification. The mean follow-up was 37.7 months from surgery. Data were analyzed by SPSS software v 24.0. The postoperative average Harris Hip Score was 87.4 points (range, 40.5\u201395.7) and 91 patients scored excellent results, with more than 90 points (52.4%). Heterotopic ossifications were seen in 12 patients (6.9%) and correlated to patient weight, surgical timing, and hemoglobin values. There were three cases of dislocation (1.7%) that significantly correlated with cup inclination (R 2\u2009=\u200917.9; p\u2009=\u20090.018). One cup underwent early revision because of undersizing of the component and subsequent lack of integration, thus leading to an overall survivorship of 99.4%. In conclusion, excellent medium-term functional outcome, patient satisfaction, and low complications rate were observed for the studied implant. A higher incidence of heterotopic ossifications was significantly correlated to patient weight, surgical time, blood loss, and transfusions. Also, inclination of the acetabular cup proved to be correlated to hip dislocation

Modeled microgravity affects fibroblast functions related to wound healing

Wound healing is crucial for the survival of an organism. Therefore, in the perspective of space exploration missions, it is important to understand if and how microgravity conditions affect the behavior of the cell populations involved in wound healing and the evolution of the process. Since fibroblasts are the major players in tissue repair, this study was focused on the behavior of fibroblasts in microgravity conditions, modeled by a RCCS. Cell cytoskeleton was studied by immunofluorescence microscopy, the ability to migrate was assessed by microchemotaxis and scratch assay, and the expression of markers of fibroblast activation, angiogenesis, and inflammation was assessed by western blot. Results revealed that after cell exposure to modeled microgravity conditions, a thorough rearrangement of microtubules occurred and α-SMA bundles were replaced by a tight network of faulty and disorganized filaments. Exposure to modeled microgravity induced a decrease in α-SMA and E-CAD expressions. Also, the expression of the pro-angiogenic protein VEGF decreased, while that of the inflammatory signal COX-2 increased. Fibroblast ability to adhere, migrate, and respond to chemoattractants (PRP), closely related to cytoskeleton integrity and membrane junctions, was significantly impaired. Nevertheless, PRP was able to partially restore fibroblast migration