GUILHERME ALVES LEPSKI
Projetos de Pesquisa
Unidades Organizacionais
Instituto Central, Hospital das Clínicas, Faculdade de Medicina - Médico
LIM/26 - Laboratório de Pesquisa em Cirurgia Experimental, Hospital das Clínicas, Faculdade de Medicina - Líder
LIM/26 - Laboratório de Pesquisa em Cirurgia Experimental, Hospital das Clínicas, Faculdade de Medicina - Líder
6 resultados
Resultados de Busca
Agora exibindo 1 - 6 de 6
- Intraoperative assistive technologies and insular gliomas surgery: Results from a volumetry-based retrospective cohort(2016) LEPSKI, Guilherme; BARBOSA, Breno Jose Alencar Pires; DIMOSTHENI, Artemisia; TEIXEIRA, Manoel Jacobsen; TATAGIBA, Marcos
- Adult Neurogenesis and Glial Oncogenesis: When the Process Fails(2014) BATISTA, Chary Marquez; MARIANO, Eric Domingos; BARBOSA, Breno Jose Alencar Pires; MORGALLA, Matthias; MARIE, Suely Kazue Nagahashi; TEIXEIRA, Manoel Jacobsen; LEPSKI, GuilhermeMalignant brain tumors, including glioblastoma multiforme (GBM), are known for their high degree of invasiveness, aggressiveness, and lethality. These tumors are made up of heterogeneous cell populations and only a small part of these cells (known as cancer stem cells) is responsible for the initiation and recurrence of the tumor. The biology of cancer stem cells and their role in brain tumor growth and therapeutic resistance has been extensively investigated. Recent work suggests that glial tumors arise from neural stem cells that undergo a defective process of differentiation. The understanding of this process might permit the development of novel treatment strategies targeting cancer stem cells. In the present review, we address the mechanisms underlying glial tumor formation, paying special attention to cancer stem cells and the role of the microenvironment in preserving them and promoting tumor growth. Recent advancements in cancer stem cell biology, especially regarding tumor initiation and resistance to chemo-or radiotherapy, have led to the development of novel treatment strategies that focus on the niche of the stem cells that make up the tumor. Encouraging results from preclinical studies predict that these findings will be translated into the clinical field in the near future.
- Insular gliomas and the role of intraoperative assistive technologies: Results from a volumetry-based retrospective cohort(2016) BARBOSA, Breno Jose Alencar Pires; DIMOSTHENI, Artemisia; TEIXEIRA, Manoel Jacobsen; TATAGIBA, Marcos; LEPSKI, GuilhermeIntroduction: In the field of Glioma surgery, there has been an increasing interest in the use of assistive technologies to overcome the difficulty of preserving brain function while improving surgical radicality. In most reports, tumor localization has seldom been considered a variable and the role of intraoperative adjuncts is yet to be determined for gliomas of the insula. Objectives: To evaluate the efficacy of fluorescence-guided resection with 5-ALA, intraoperative neurophysiological monitoring (IOM), neuronavigation, and tractography in the Extent of Resection (EOR), functionality scores, overall survival (OS) and progression-free survival (PFS) in a retrospective cohort of insular gliomas. Methods: We reviewed all cases of insular tumors operated on at the Department of Neurosurgery, University Hospital of Tubingen Germany, between May 2008 and November 2013. EOR was determined by volumetric analysis. Mann Whitney, Chi-square and Kaplan Meier functions were used for assessment of each technology's effect on primary and secondary outcomes. Results: 28 cases (18 men (64%) and 10 women (36%); median age at diagnosis: 52.5 years, range 12 - 59) were considered eligible for analysis. High grade and low grade gliomas accounted for 20 (71%) and 8 (29%) cases, respectively. The most used technologies were IOM (64%) and Neuronavigation (68%). 5-ALA was the only technique associated with EOR >= 90% (p = 0.05). Tractography determined improvement in the Karnofsky Performance Scale (50% vs. 5% cases improved, p = 0.02). There was a positive association between the use of neuronavigation and overall survival (23 vs. 27.4 months, p = 0.03), but the use of 5-ALA was associated with shorter OS (34.8 vs. 21.1 months, p = 0.01) and PFS (24.4 vs. 11.8, p = 0.01). Conclusions: We demonstrate for the first time that for insular gliomas 5-ALA plays a role in achieving higher EOR, although this technology was associated with poor OS and PFS; also tractography and neuronavigation can be of great importance in the treatment of insular gliomas as they determined better functionality and OS in this study, respectively. Prospective studies with a more prominent sample and proper multivariate analysis will help determine the real benefit of these adjuncts in the setting of insular gliomas.
- Current perspectives in stem cell therapy for spinal cord repair in humans: a review of work from the past 10 years(2014) MARIANO, Eric Domingos; BATISTA, Chary Marquez; BARBOSA, Breno Jose Alencar Pires; MARIE, Suely Kazue Nagahashi; TEIXEIRA, Manoel Jacobsen; MORGALLA, Matthias; TATAGIBA, Marcos; LI, Jun; LEPSKI, GuilhermeSpinal cord injury (SCI) and amyotrophic laterals sclerosis (ALS) are devastating neurological conditions that affect individuals worldwide, significantly reducing quality of life, both for patients and their relatives. Objective: The present review aims to summarize the multiple restorative approaches being developed for spinal cord repair, the use of different stem cell types and the current knowledge regarding stem cell therapy. Method: Review of the literature from the past 10 years of human studies using stem cell transplantation as the main therapy, with or without adjuvant therapies. Conclusion: The current review offers an overview of the state of the art regarding spinal cord restoration, and serves as a starting point for future studies.
- Intraoperative assistive technologies and extent of resection in glioma surgery: a systematic review of prospective controlled studies(2015) BARBOSA, Breno Jose Alencar Pires; MARIANO, Eric Domingos; BATISTA, Chary Marquez; MARIE, Suely Kazue Nagahashi; TEIXEIRA, Manoel Jacobsen; PEREIRA, Carlos Umberto; TATAGIBA, Marcos Soares; LEPSKI, Guilherme AlvesSeveral studies published to date about glioma surgery have addressed the validity of using novel technologies for intraoperative guidance and potentially improved outcomes. However, most of these reports are limited by questionable methods and/or by their retrospective nature. In this work, we performed a systematic review of the literature to address the impact of intraoperative assistive technologies on the extent of resection (EOR) in glioma surgery, compared to conventional unaided surgery. We were also interested in two secondary outcome variables: functional status and progression-free survival. We primarily used PubMed to search for relevant articles. Studies were deemed eligible for our analysis if they (1) were prospective controlled studies; (2) used EOR as their primary target outcome, assessed by MRI volumetric analysis; and (3) had a homogeneous study population with clear inclusion criteria. Out of 493 publications identified in our initial search, only six matched all selection criteria for qualitative synthesis. Currently, the evidence points to 5-ALA, DTI functional neuronavigation, neurophysiological monitoring, and intraoperative MRI as the best tools for improving EOR in glioma surgery. Our sample and conclusions were limited by the fact that studies varied in terms of population characteristics and in their use of different volumetric analyses. We were also limited by the low number of prospective controlled trials available in the literature. Additional evidence-based high-quality studies assessing cost-effectiveness should be conducted to better determine the benefits of intraoperative assistive technologies in glioma surgery.
- Do cyclin e levels correlate with recurrence in meningioma? Results from an observational study.(2016) LEPSKI, Guilherme; BARBOSA, Breno Jose Alencar Pires; SANTANA JUNIOR, Pedro Augustto de; SHINJO, Sueli Mieko Oba; AGUIAR, Paulo Henrique Pires de; CASTRO, Isac de; TEIXEIRA, Manoel Jacobsen; MARIE, Suely Kazue Nagahashi