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1.
J Acoust Soc Am ; 152(3): 1932, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36182282

RESUMO

Project-based learning engages students in practical activities related to course content and has been demonstrated to improve academic performance. Due to its reported benefits, this form of active learning was incorporated with an ongoing research project into an introductory, graduate-level Musical Acoustics course at the Peabody Institute of The Johns Hopkins University. Students applied concepts from the course to characterize a contact sensor with a polymer diaphragm for musical instrument recording. Assignments throughout the semester introduced students to completing a literature review, planning an experiment, collecting and analyzing data, and presenting results. While students were given broad goals to understand the performance of the contact sensor compared to traditional microphones, they were allowed independence in determining the specific methods used. The efficacy of the course framework and research project was assessed with student feedback provided through open-ended prompts and Likert-type survey questions. Overall, the students responded positively to the project-based learning and demonstrated mastery of the course learning objectives. The work provides a possible framework for instructors considering using project-based learning through research in their own course designs.


Assuntos
Acústica , Aprendizagem Baseada em Problemas , Retroalimentação , Humanos
2.
Lancet Oncol ; 20(8): 1148-1159, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31296491

RESUMO

BACKGROUND: Pathological complete response to preoperative treatment in adults with soft-tissue sarcoma can be achieved in only a few patients receiving radiotherapy. This phase 2-3 trial evaluated the safety and efficacy of the hafnium oxide (HfO2) nanoparticle NBTXR3 activated by radiotherapy versus radiotherapy alone as a pre-operative treatment in patients with locally advanced soft-tissue sarcoma. METHODS: Act.In.Sarc is a phase 2-3 randomised, multicentre, international trial. Adults (aged ≥18 years) with locally advanced soft-tissue sarcoma of the extremity or trunk wall, of any histological grade, and requiring preoperative radiotherapy were included. Patients had to have a WHO performance status of 0-2 and a life expectancy of at least 6 months. Patients were randomly assigned (1:1) by an interactive web response system to receive either NBTXR3 (volume corresponding to 10% of baseline tumour volume at a fixed concentration of 53·3 g/L) as a single intratumoural administration before preoperative external-beam radiotherapy (50 Gy in 25 fractions) or radiotherapy alone, followed by surgery. Randomisation was stratified by histological subtype (myxoid liposarcoma vs others). This was an open-label study. The primary endpoint was the proportion of patients with a pathological complete response, assessed by a central pathology review board following European Organisation for Research and Treatment of Cancer guidelines in the intention-to-treat population full analysis set. Safety analyses were done in all patients who received at least one puncture and injection of NBTXR3 or at least one dose of radiotherapy. This study is registered with ClinicalTrials.gov, number NCT02379845, and is ongoing for long-term follow-up, but recruitment is complete. FINDINGS: Between March 3, 2015, and Nov 21, 2017, 180 eligible patients were enrolled and randomly assigned and 179 started treatment: 89 in the NBTXR3 plus radiotherapy group and 90 in the radiotherapy alone group. Two patients in the NBTXR3 group and one patient in the radiotherapy group were excluded from the efficacy analysis because they were subsequently discovered to be ineligible; thus, a total of 176 patients were analysed for the primary endpoint in the intention-to-treat full analysis set (87 in the NBTXR3 group and 89 in the radiotherapy alone group). A pathological complete response was noted in 14 (16%) of 87 patients in the NBTXR3 group and seven (8%) of 89 in the radiotherapy alone group (p=0·044). In both treatment groups, the most common grade 3-4 treatment-emergent adverse event was postoperative wound complication (eight [9%] of 89 patients in the NBTXR3 group and eight [9%] of 90 in the radiotherapy alone group). The most common grade 3-4 adverse events related to NBTXR3 administration were injection site pain (four [4%] of 89) and hypotension (four [4%]) and the most common grade 3-4 radiotherapy-related adverse event was radiation skin injury in both groups (five [6%] of 89 in the NBTXR3 group and four [4%] of 90 in the radiotherapy alone group). The most common treatment-emergent grade 3-4 adverse event related to NBTXR3 was hypotension (six [7%] of 89 patients). Serious adverse events were observed in 35 (39%) of 89 patients in the NBTXR3 group and 27 (30%) of 90 patients in the radiotherapy alone group. No treatment-related deaths occurred. INTERPRETATION: This trial validates the mode of action of this new class of radioenhancer, which potentially opens a large field of clinical applications in soft-tissue sarcoma and possibly other cancers. FUNDING: Nanobiotix SA.


Assuntos
Háfnio/uso terapêutico , Nanopartículas/uso terapêutico , Óxidos/uso terapêutico , Radiossensibilizantes/uso terapêutico , Sarcoma/terapia , Neoplasias de Tecidos Moles/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radioterapia/métodos , Adulto Jovem
3.
Acta Chir Belg ; 119(2): 118-122, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30774002

RESUMO

INTRODUCTION: Perivascular epithelioid cell tumor (PEComa) is a family of rare mesenchymal tumors composed of histologically and immunohistochemically distinctive perivascular epithelioid cells (PECs). These tumors have been described at multiple anatomic sites. PEComas presenting in bone are especially rare and they have been reported to be either primary or metastatic lesions. None of them is located at the level of the foot. PATIENT: We report on a case of primary bone PEComa of the talus, the first one to be published to the best of our knowledge. Treatment and result: Limb sparing surgical treatment has been done using intralesional tumor removal, burring and application of argon beam at the tumor walls and primary filling of the tumor cavity by bone cement with so far absence of any tumor recurrence documented by multiple histological sections at second look operation nine months after primary surgery, where cement has been replaced by autologous bone graft, and by subsequent follow-up. CONCLUSIONS: PEComa is a very rare tumor, and its presence in bone is especially rare. The here reported case of PEComa presenting at the level of the talus is, to the best of our knowledge, the first case to be reported in the literature.


Assuntos
Neoplasias Ósseas/cirurgia , Salvamento de Membro/métodos , Neoplasias de Células Epitelioides Perivasculares/cirurgia , Tálus/cirurgia , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias de Células Epitelioides Perivasculares/diagnóstico por imagem , Neoplasias de Células Epitelioides Perivasculares/patologia , Tálus/diagnóstico por imagem , Tálus/patologia
4.
Indian J Surg Oncol ; 15(Suppl 1): 119-126, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38545591

RESUMO

The free vascularised fibular graft represents the mainstay of intercalary bone defect reconstruction after tumour resection. Different reconstruction techniques are described, favouring internal fixation and possibly overlooking potential advantages of external fixation. This series is a description of the technique performed at our institution using an external fixator for the reconstruction of segmental bone defects which enables to maintain limb length and rotational alignment after large segmental bone resection. Data collected were demographic, surgical and histological data, perioperative complications and postoperative data. Eighteen different complications were encountered in seven patients. Mean reoperation rate was 1.3 per patient but no patient required further interventions in order to correct limb length or rotational alignment. Pin-track infection rate was 6%. The limb salvage rate was 100%. Solid final bone healing was obtained in all patients. External fixation for the reconstruction of intercalary bone defects after tumour resection is a safe technique which might offer the advantage of limb length and alignment preservation.

5.
Acta Orthop Belg ; 78(4): 558-63, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23019793

RESUMO

Early and late infection as well as loosening and mechanical failure are among the postoperative complications most often reported following reconstruction with a tumour prosthesis in patients with a sarcoma around the knee. Scarce instances of periprosthetic fractures have been reported. The literature includes the description of two patients with such a complication, however no treatment recommendation was detailed in those articles. We recorded in our experience two patients with a traumatic fracture following a massive prosthetic bone and joint replacement after major resection for a bone sarcoma. The surgical treatment was open reduction and internal fixation using a cable and plate system, allowing preservation of the prosthesis and providing stable fracture fixation and excellent fracture healing.


Assuntos
Neoplasias Ósseas/cirurgia , Traumatismos do Joelho/cirurgia , Prótese do Joelho , Osteossarcoma/cirurgia , Patela/lesões , Fraturas Periprotéticas/cirurgia , Adolescente , Neoplasias Ósseas/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteossarcoma/complicações , Fraturas Periprotéticas/complicações
6.
Clin Orthop Relat Res ; 468(7): 1991-6, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20020334

RESUMO

BACKGROUND: Alendronate is known for its ability to reduce bone loss in osteoporotic and osseous metastatic conditions. Its long-term effects remain unclear although several reports describe cases of proximal femur stress fractures associated with long-term alendronate use. CASE DESCRIPTION: We report the cases of four women who sustained low-energy subtrochanteric or femoral shaft stress fractures while being on alendronate therapy for more than 5 years. All radiographs showed typical patterns consisting of a transverse fracture line with external cortical bone reaction and medial cortical spike. Alendronate discontinuation along with nonoperative treatment was sufficient for one patient, whereas surgical stabilization was required in three patients. LITERATURE REVIEW: The side effects of alendronate therapy include osteonecrosis of the jaw, esophageal irritation, and musculoskeletal pain. Several cases of insufficiency femoral fractures associated with prolonged alendronate use have been reported. Their radiographic pattern and clinical presentation are consistent with our observations. Although various hypotheses have been suggested, the physiopathogenesis of these stress fractures is not completely understood. PURPOSES AND CLINICAL RELEVANCE: Although bisphosphonates play an important role in preventing pathologic fractures in patients with cancer, these subtrochanteric stress fractures associated with prolonged use of alendronate should not be ignored.


Assuntos
Alendronato/efeitos adversos , Conservadores da Densidade Óssea/efeitos adversos , Fraturas do Fêmur/etiologia , Fraturas de Estresse/etiologia , Idoso , Pinos Ortopédicos , Feminino , Fraturas do Fêmur/diagnóstico por imagem , Fraturas do Fêmur/cirurgia , Fixação Intramedular de Fraturas/instrumentação , Fixação Intramedular de Fraturas/métodos , Fixação Intramedular de Fraturas/reabilitação , Fraturas de Estresse/diagnóstico por imagem , Fraturas de Estresse/cirurgia , Humanos , Pessoa de Meia-Idade , Radiografia , Resultado do Tratamento
7.
Acta Orthop Belg ; 76(6): 844-9, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21302587

RESUMO

Extraosseous Ewing's sarcoma represents about 5% of the Ewing family of tumours. Two cases in adult patients are presented, emphasizing the complexity of a multi-modality treatment approach of this tumour. Clinical presentation, chemotherapeutical, surgical and radiotherapeutical approaches are discussed. A thorough literature search was done to correlate our therapeutic attitude with current knowledge of this very rare disease.


Assuntos
Sarcoma de Ewing/diagnóstico , Adolescente , Adulto , Fosfatase Alcalina/sangue , Desmineralização Patológica Óssea , Feminino , Humanos , Tumores Neuroectodérmicos Primitivos Periféricos/diagnóstico , Sarcoma de Ewing/patologia , Sarcoma de Ewing/fisiopatologia
8.
Acta Orthop Belg ; 74(6): 885-90, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19205342

RESUMO

Chondrosarcomas of the spine are rare and are difficult to treat. Three cases of chondrosarcoma are presented, and a series compiling similar cases reported in the literature was established. This study shows that chondrosarcomas of the spine are generally smaller, more difficult to excise, and followed by higher local recurrence compared with chondrosarcomas in the peripheral skeleton. The most important prognostic factor for local control is wide or marginal tumour resection.


Assuntos
Condrossarcoma/cirurgia , Neoplasias da Coluna Vertebral/cirurgia , Adulto , Condrossarcoma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Neoplasias da Coluna Vertebral/patologia
9.
Crit Rev Oncol Hematol ; 62(1): 9-15, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17141519

RESUMO

Soft tissue sarcoma is a heterogeneous group of rare tumours arising predominantly from the embryonic mesoderm. While the prognosis is excellent for patients diagnosed at an early stage and treated by adequate surgery, unresectable or advanced metastatic diseases shrink the overall survival at 5 years dramatically to less than 10%. For metastatic soft tissue sarcoma, the armamentarium of effective chemotherapeutic agents is limited, especially when patients failed anthracycline- and/or ifosfamide-based chemotherapy. Fortunately, progress in the understanding of molecular biology and pathogenesis of soft tissue sarcomas has been made recently and should in the near future translate into molecular tumour characterization and the development of new therapeutic strategies. In this review, we briefly describe the status of current treatment strategies for soft tissue sarcoma. We will focus on the new and emerging compounds including recent developments of targeted therapy and cytotoxics such as antiangiogenic and immunomodulatory drugs, Bcl-2 antisense therapy, raf kinase inhibitors, heat shock protein modulators, anti-cytotoxic T lymphocyte-associated antigen (CTLA)-4 monoclonal antibody, proteasome inhibitors, minor groove binders, topoisomerase I inhibitors, and other agents being extensively developed in these solid tumours.


Assuntos
Antineoplásicos/uso terapêutico , Sarcoma/tratamento farmacológico , Neoplasias de Tecidos Moles/tratamento farmacológico , Animais , Ensaios Clínicos como Assunto , Sistemas de Liberação de Medicamentos , Humanos
10.
Acta Orthop Belg ; 72(6): 769-71, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17260618

RESUMO

Acute colonic pseudo-obstruction (Ogilvie's syndrome) is characterised by abdominal distension and massive colonic dilatation without any mechanical cause of obstruction. The pathogenesis remains unknown but likely involves imbalance between sympathetic and parasympathetic colon innervation. This syndrome is well known in orthopaedic surgery, as trauma and orthopaedic surgery have been reported as aetiological factors. Some cases have been reported after cervical discectomy. We report a case of Ogilvie's syndrome after lumbar spine surgery. Medical treatment including parasympathetic agent was unsuccessful and the patient underwent a right colectomy. The pathophysiology and treatment are discussed based on a review of the literature.


Assuntos
Pseudo-Obstrução do Colo/etiologia , Vértebras Lombares/cirurgia , Complicações Pós-Operatórias , Neoplasias da Coluna Vertebral/cirurgia , Idoso , Ceco/diagnóstico por imagem , Ceco/patologia , Colectomia , Pseudo-Obstrução do Colo/diagnóstico , Pseudo-Obstrução do Colo/diagnóstico por imagem , Pseudo-Obstrução do Colo/cirurgia , Dilatação Patológica , Humanos , Masculino , Mieloma Múltiplo/patologia , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/cirurgia , Neoplasias da Coluna Vertebral/secundário , Tomografia Computadorizada por Raios X
11.
Ann Pathol ; 23(4): 336-9, 2003 Sep.
Artigo em Francês | MEDLINE | ID: mdl-14597897

RESUMO

We report an additional case of inflammatory leiomyosarcoma, arising in the shoulder of a 31-year-old male. The rare inflammatory variant of leiomyosarcoma tends to affect young adults. Histologically it is characterized by a prominent lymphohistiocytic infiltrate often masking fascicles of spindle cells, as well as the presence of clusters of xanthoma cells and psammoma bodies. Smooth muscle differentiation is supported by desmin and smooth muscle actin expression. The differential diagnosis includes so-called inflammatory 'malignant fibrous histiocytoma'and inflammatory myofibroblastic tumor. The outcome of this variant seems to be favorable.


Assuntos
Leiomiossarcoma/patologia , Ombro , Neoplasias de Tecidos Moles/patologia , Adulto , Humanos , Masculino
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