2,240 research outputs found
Supracricoid partial laryngectomy as salvage surgery for radiation therapy failure.
The main concern in the treatment of laryngeal carcinomas is tumor control with preservation of laryngeal functions. We believe that salvage supracricoid partial laryngectomy (SPL) should be carefully considered in selected cases of radiotherapy failure, because it can offer the possibility of achieving adequate tumor control with preservation of laryngeal functions.A series of 31 patients who underwent an SPL as salvage procedure after radiotherapy failure was reviewed.Locoregional control rate was 75\%, with 60\% 5-year overall survival; no patients were lost to follow-up, and a death-from-disease rate of 19.35\% was recorded. Restoration of laryngeal functions was achieved in 89.29\% of the patients. No statistically significant differences were found in locoregional control regarding anterior commissure involvement, elective neck dissection versus wait-and-see policy, pathologic positive neck disease, and restage I-II versus restage III-IV.The oncologic and functional results indicate the consistency of salvage SPL, proposing this type of operation as a serious alternative to total laryngectomy in carefully selected cases
Marine dual-fuel engines power smart management by hybrid turbocharging systems
The performance of a marine dual-fuel engine, equipped with an innovative hybrid turbocharger producing electric power to satisfy part of the shipâs electric load, is presented by a simulation comparison with the traditional turbocharging technology. The two distinct fuel types, combined with the hybrid turbocharger, involve a substantial change in the engine control modes, resulting in more flexible and efficient power management. Therefore, the investigation requires a numerical analysis depending on the engine load variation, in both fuelling modes, to highlight different behaviours. In detail, a dual-fuel engine simulation model is validated for a particular application in order to perform a complete comparison, reported in tabular and graphical form, between the two examined turbocharging solutions. The simulation analysis is presented in terms of the engine working data and overall energy conversion efficiency
3d collagen hydrogel promotes in vitro langerhans islets vascularization through ad-mvfs angiogenic activity
Adipose derived microvascular fragments (ad-MVFs) consist of effective vascularization units able to reassemble into efficient microvascular networks. Because of their content in stem cells and related angiogenic activity, ad-MVFs represent an interesting tool for applications in regenerative medicine. Here we show that gentle dissociation of rat adipose tissue provides a mixture of ad-MVFs with a length distribution ranging from 33â955 ”m that are able to maintain their original morphology. The isolated units of ad-MVFs that resulted were able to activate transcriptional switching toward angiogenesis, forming tubes, branches, and entire capillary networks when cultured in 3D collagen type-I hydrogel. The proper involvement of metalloproteases (MMP2/MMP9) and serine proteases in basal lamina and extracellular matrix ECM degradation during the angiogenesis were concurrently assessed by the evaluation of alpha-smooth muscle actin (αSMA) expression. These results suggest that collagen type-I hydrogel provides an adequate 3D environment supporting the activation of the vascularization process. As a proof of concept, we exploited 3D collagen hydrogel for the setting of ad-MVFâislet of Langerhans coculture to improve the islets vascularization. Our results suggest potential employment of the proposed in vitro system for regenerative medicine applications, such as the improving of the islet of Langerhans engraftment before transplantation
Neural Crest-Derived Chondrocytes Isolation for Tissue Engineering in Regenerative Medicine
Chondrocyte transplantation has been successfully tested and proposed as a clinical procedure aiming to repair articular cartilage defects. However, the isolation of chondrocytes and the optimization of the enzymatic digestion process, as well as their successful in vitro expansion, remain the main challenges in cartilage tissue engineering. In order to address these issues, we investigated the performance of recombinant collagenases in tissue dissociation assays with the aim of isolating chondrocytes from bovine nasal cartilage in order to establish the optimal enzyme blend to ensure the best outcomes of the overall procedure. We show, for the first time, that collagenase H activity alone is required for effective cartilage digestion, resulting in an improvement in the yield of viable cells. The extracted chondrocytes proved able to grow and activate differentiation/dedifferentiation programs, as assessed by morphological and gene expression analyses
Neuroendocrine neoplasms of the esophagus and stomach.
Esophageal neuroendocrine neoplasms (E-NENs) are much rarer than other gastro-entero-pancreatic neuroendocrine neoplasms, the majority showing aggressive behavior with early dissemination and poor prognosis. Among E-NENs, exceptionally rare well differentiated neuroendocrine tumors (E-NET) and more frequent esophageal poorly differentiated neuroendocrine carcinomas (E-NEC) and mixed neuroendocrine-non neuroendocrine neoplasms (MiNEN) can be recognized. E-NECs usually exhibit a small cell morphology or mixed small and large cells. Esophageal MiNEN are composed of NEC component admixed with adenocarcinoma or squamous cell carcinoma. Gastric (G) NENs encompass a wide spectrum of entities ranging from indolent G-NETs to highly aggressive G-NECs and MiNENs. Among G-NETs, ECL-cell NETs are the most common and, although composed of histamine-producing cells, are a heterogeneous group of neoplastic proliferations showing different clinical and prognostic features depending on the patient's clinico-pathological background including the morphology of the peri-tumoral mucosa, gastrin serum levels, presence or absence of antral G-cell hyperplasia, and presence or absence of MEN1 syndrome. In general, NET associated with hypergastrinemia show a better outcome than NET not associated with hypergastrinemia. G-NECs and MiNENs are aggressive neoplasms more frequently observed in males and associated with a dismal prognosis
Prognostic role of pneumonia in supracricoid and supraglottic laryngectomies.
The goal of this study was to identify host and tumour factors associated with postoperative pneumonia (PP) in a selected population of laryngeal cancer patients, treated by partial laryngectomy in 20 years at our Institution and to assess its potential prognostic impact. Clinical records of 416 consecutive patients were retrospectively reviewed. Tobacco consumption, body mass index (BMI), previous pulmonary disease, age, sex, preoperative blood gas analysis values, tumour stage and type of surgery were tested as potential risk factors for PP. Finally, the prognostic impact of these variables, including PP, in terms of disease-free and actuarial survival by Kaplan-Meier and Cox analyses were evaluated. PP developed in 73 patients (16.8\%). We identified two groups of patients: 26 patients experienced an early PP within the first 7-9 days after surgery, whilst 44 experienced an ab ingestis PP following attempts of oral food intake restoration, three patients died for PP related sepsis. At multivariate Cox analysis, age older than 60 years and BMI greater than 30 were statistically associated with early PP; whereas male gender and laryngectomy with neck dissection were statistically related to a higher risk of ab ingestis PP. Interestingly, the occurrence of early PP was a negative independent prognostic factor for 5-years disease-free and actuarial survival (p=0.049 and p=0.001, respectively). The occurrence of early-onset pneumonia in laryngeal cancer patients selected for conservative laryngectomies is predictable and associated with poor clinical outcome
Sialoendoscopy: state of the art, challenges and further perspectives. Round Table, 101st SIO National Congress, Catania 2014
This draft of the Official Round Table held during the 101st SIO National Congress is an updated review on sialoendoscopy, a technique used for diagnosis and treatment of obstructive pathologies of salivary glands in a minimally invasive fashion. This review treats many aspects of salivary gland endoscopy, starting from anatomy to deal with the more advanced surgical techniques and analyses the main decisional algorithms proposed in the literature. In addition, particular attention was directed to the current limitations of this technique and to the potential developments that sialoendoscopy could have in the near future
Metamodels of a gas turbine powered marine propulsion system for simulation and diagnostic purposes
The paper presents the application of artificial neural network for simulation and diagnostic purposes applied to a gas turbine powered marine propulsion plant. A simulation code for the propulsion system, developed by the authors, has been extended to take into account components degradation or malfunctioning with the addition of performance reduction coefficients. The above coefficients become input variables to the analysis method and define the system status at a given operating point. The simulator is used to generate databases needed to perform a variable selection analysis and to tune response surfaces for both direct (simulation) and inverse (diagnostic) purposes. The application of the methodology to the propulsion system of an existing frigate version demonstrate the potential of the approach
Nanoformulations based on collagenases loaded into halloysite/VeegumÂź clay minerals for potential pharmaceutical applications
The design and development of nanomaterials capable of penetrate cancer cells is fundamental when anticancer therapy is involved. The use of collagenase (Col) is useful since this enzyme can degrade collagen, mainly present in the tumor extracellular matrix. However, its use is often limited since collagenase suffers from inactivation and short half-life. Use of recombinant ultrapure collagenase or carrier systems for their delivery are among the strategies adopted to increase the enzyme stability. Herein, based on the more stability showed by recombinant enzymes and the possibility to use them in anticancer therapy, we propose a novel strategy to further increase their stability by using halloysite nanotubes (HNTs) as carrier. ColG and ColH were supramolecularly loaded onto HNTs and used as fillers for Veegum gels. The systems could be used for potential local administration of collagenases for solid tumor treatment. All techniques adopted for characterization showed that halloysite interacts with collagenases in different ways depending with the Col considered. Furthermore, the hydrogels showed a very slow release of the collagenases within 24 h. Finally, biological assays were performed by studying the digestion of a type-I collagen matrix highlighting that once released the Col still possessed some activity. Thus we developed carrier systems that could further increase the high recombinant collagenases stability, preventing their inactivation in future in vivo applications for potential local tumor treatment
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