941 research outputs found

    Geometria e progetto. Ipotesi di riuso per il palazzo Vernazza a Castri

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    Dall’Antichità al Rinascimento, da Pitagora a Keplero, aritmetica, geometria, musica e astronomia hanno indagato il numero, lo spazio, il suono e il movimento dei corpi celesti. Queste quattro discipline venivano già pensate e insegnate da Platone come un insieme unitario, che fondeva lo studio degli oggetti matematici con l’aspirazione filosofica al vero, al bello e al bene. Il Quadrivium viene reinterpretato in questo lavoro e l’edificio diviene testimone, testo parlante, memoria scritta in molti linguaggi e restituisce al lettore di oggi un patrimonio un tempo riservato a pochi. Il Palazzo Vernazza di Castri di Lecce è studiato in questa sperimentazione progettuale a partire dalla riscoperta della sua misura storica, con il contributo delle moderne tecniche di rilievo che hanno supportato questi studi, allo scopo di assegnare al progetto contemporaneo una base linguistica invisibile, un alfabeto che strutturi la costruzione del nuovo

    The surgical treatment of pelvic bone metastases

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    Pelvic bone metastases are a growing concern in the field of orthopedic surgery. Patients with pelvic metastasis are individually different with different needs of treatment in order to attain the best possible quality of life despite the advanced stage of disease. A holistic collaboration among the oncologist, radiation therapist, and orthopedic surgeon is mandatory. Special attention has to be directed to osteolytic lesions in the periacetabular region as they can provoke pathological fractures and subsequent functional impairment. Different reconstruction techniques for the pelvis are available; the choice depends on the patient's prognosis, size of the bone defect, and response of the tumor to adjuvant treatment. If all the conservative treatments are exhausted and the patient is not eligible for surgery, one of the various percutaneous ablation procedures can be considered. We propose a pelvic analogue to the treatment algorithm in long bone metastasis and a scoring system in pelvic metastasis. This algorithm aims to simplify the teamwork and to avoid under-or overtreatment of pelvic bone metastases

    Evolutive pattern of Calomys hummelincki (Husson, 1960; Rodentia, Sigmodontinae) inferred from cytogenetic and allozymic data.

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    The main purpose of this research was to understand the evolutive history of the sigmodontine rodent Calomys hummelincki (Husson 1960), tribe Phyllotini from chromosomal and allozymic data, and evaluate the hypotheses that explains the colonization and evolution of sigmodontine rodents in South America. C. hummelincki is restricted to the Northern South American region, which comprises Venezuela, Aruba and Curaçao islands where specimen sampling was done. The cytogenetic analysis showed that all populations studied have the same diploid number (2n=60) and fundamental number (FN=64). Constitutive heterochromatin was observed on pericentromeric positions in almost all chromosomes. NOR regions were observed on four pairs of acrocentric chromosomes. G-banding allowed us to identify almost all pair positions in the C. hummelincki chromosome complement. The G-banding also permitted a comparison of the C. hummelincki pattern with those published for C. callidus, C. venustus and C. laucha species. G-banded information indicates that hummelincki is not directly derived from laucha. The results are constrained with published allozymic and molecular data obtained in previous studies. The overall analysis seems to support Reig´s hypothesis of a south to north colonization of genus Calomys in South America

    Analysis of a Preliminary microRNA Expression Signature in a Human Telangiectatic Osteogenic Sarcoma Cancer Cell Line

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    Telangiectatic osteosarcoma (TOS) is an aggressive variant of osteosarcoma (OS) with distinctive radiographic, gross, microscopic features, and prognostic implications. Despite several studies on OS, we are still far from understanding the molecular mechanisms of TOS. In recent years, many studies have demonstrated not only that microRNAs (miRNAs) are involved in OS tumorigenesis, development, and metastasis, but also that the presence in high-grade types of OS of cancer stem cells (CSCs) plays an important role in tumor progression. Despite these findings, nothing has been described previously about the expression of miRNAs and the presence of CSCs in human TOS. Therefore, we have isolated/characterized a putative CSC cell line from human TOS (TOS-CSCs) and evaluated the expression levels of several miRNAs in TOS-CSCs using real-time quantitative assays. We show, for the first time, the existence of CSCs in human TOS, highlighting the in vitro establishment of this unique stabilized cell line and an identification of a preliminary expression of the miRNA profile, characteristic of TOS-CSCs. These findings represent an important step in the study of the biology of one of the most aggressive variants of OS and the role of miRNAs in TOS-CSC behavior. View Full-Tex

    Allograft Reconstruction of the Extensor Mechanism after Resection of Soft Tissue Sarcoma

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    Soft tissue tumors around the knee joint still pose problems for the excision and subsequent reconstruction. Methods. In the 6 included patients the soft tissue sarcoma has its base on the anterior surface of the extensor mechanism and expands towards the skin. The entire extensor apparatus (quadriceps tendon, patella, and patellar tendon) was resected and replaced by a fresh-frozen allograft. Results. The mean follow-up was 6.7 years (range: 2-12.4 years). In two patients a local recurrence occurred, resulting in a 5-year local recurrence-free rale of 66.7% (95% CI: 19.5%-90.4%). Distant metastases were found in 4 patients resulting in a 5-year metastasis-free rate of 33.3% (95% CI: 4.6%-67.5%). Two patients underwent at least one revision surgery, including one patient in whom the allograft had to be removed. According to the ISOLS function score 24.7 points (range: 19-28 points) were achieved at the last follow-up. The mean active flexion of the knee joint was 82.5 degrees (range: 25-120 degrees) and a mean extension lag of 10 degrees (range: 0-30 degrees) was observed. Conclusions. Ihe replacement of the extensor mechanism by an allograft is a reasonable option, allowing wide margins and restoration of active extension in most patients. Trial Registration. The presented study is listed on the ISRCTN registry with trial number ISRCTN63060594

    Proximal Humerus Reconstruction after Tumor Resection: An Overview of Surgical Management

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    Proximal humerus is one of the anatomical sites that are most frequently involved by bone and soft tissue malignant tumors. Alone or in association with adjuvant treatments, surgery represents the main therapeutic option to treat and eradicate these diseases. Once the first-line option, in the last decades, amputation lost its role as treatment of choice for the large majority of cases in favor of the modern limb sparing surgery that promises to preserve anatomy and - as much as possible - upper limb functionality. Currently, the main approaches used to replace proximal humerus after a wide resection in oncologic surgery can be summarized in biological reconstructions (allograftsand autografts), prosthetic reconstructions (anatomic endoprostheses, total reverse shoulder prostheses), and graft-prosthetic composite reconstructions. The purpose of this overview is to present nowadays surgical options for proximal humerus reconstruction in oncological patients, with their respective advantages and disadvantages

    Custom-made 3d-printed implants as novel approach to reconstructive surgery after oncologic resection in pediatric patients

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    Recently, custom-made 3D-printed prostheses have been introduced for limb salvage surgery in adult patients, but their use has not been described in pediatric patients. A series of 11 pediatric patients (mean age 10.8 years; range 2–13) with skeletal tumors treated with custom-made implants for the reconstruction of bony defects is described. Patients were followed up every 3 months. Functional results were evaluated by the Musculoskeletal Tumor Society Score (MSTS) for upper and lower limbs. The mean follow-up was 25.7 months (range 14–44). Three patients died after a mean of 19.3 months postoperatively—two because of disease progression and the other from a previous malignancy. Three patients experienced complications related to soft tissues. One patient required device removal, debridement, and antibiotic pearls for postoperative infection. Partial osseointegration between grafts and host bone was observed within a mean of 4 months. At the final follow-up, mean MSTS score was 75%. 3D prostheses may yield biological advantages due to possible integration with the host bone and also through the use of vascularized flaps. Further research is warranted

    Establishment of Cancer Stem Cell Cultures from Human Conventional Osteosarcoma

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    The current improvements in therapy against osteosarcoma (OS) have prolonged the lives of cancer patients, but the survival rate of five years remains poor when metastasis has occurred. The Cancer Stem Cell (CSC) theory holds that there is a subset of tumor cells within the tumor that have stem-like characteristics, including the capacity to maintain the tumor and to resist multidrug chemotherapy. Therefore, a better understanding of OS biology and pathogenesis is needed in order to advance the development of targeted therapies to eradicate this particular subset and to reduce morbidity and mortality among patients. Isolating CSCs, establishing cell cultures of CSCs, and studying their biology are important steps to improving our understanding of OS biology and pathogenesis. The establishment of human-derived OS-CSCs from biopsies of OS has been made possible using several methods, including the capacity to create 3-dimensional stem cell cultures under nonadherent conditions. Under these conditions, CSCs are able to create spherical floating colonies formed by daughter stem cells; these colonies are termed "cellular spheres". Here, we describe a method to establish CSC cultures from primary cell cultures of conventional OS obtained from OS biopsies. We clearly describe the several passages required to isolate and characterize CSCs
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