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
40 resultados
Resultados de Busca
Agora exibindo 1 - 10 de 40
- Pain inhibition through transplantation of fetal neuronal progenitors into the injured spinal cord in rats(2019) BATISTA, Chary M.; MARIANO, Eric D.; DALE, Camila S.; CRISTANTE, Alexandre F.; BRITTO, Luiz R.; OTOCH, Jose P.; TEIXEIRA, Manoel J.; MORGALLA, Matthias; LEPSKI, GuilhermeNeuropathic pain after spinal cord injury (SCI) is a complex condition that responds poorly to usual treatments. Cell transplantation represents a promising therapy; nevertheless, the ideal cell type in terms of neurogenic potential and effectiveness against pain remains largely controversial. Here, we evaluated the ability of fetal neural stem cells (fNSC) to relieve chronic pain and, secondarily, their effects on motor recovery. Adult Wistar rats with traumatic SCI were treated, 10 days after injury, with intra-spinal injections of culture medium (sham) or fNSCs extracted from telencephalic vesicles (TV group) or the ventral medulla (VM group) of E/14 embryos. Sensory (von Frey filaments and hot plate) and motor (the Basso, Beattie, Bresnahan locomotor rating scale and inclined plane test) assessments were performed during 8 weeks. Thereafter, spinal cords were processed for immunofluorescence and transplanted cells were quantified by stereology. The results showed improvement of thermal hyperalgesia in the TV and VM groups at 4 and 5 weeks after transplantation, respectively. Moreover, mechanical allodynia improved in both the TV and VM groups at 8 weeks. No significant motor recovery was observed in the TV or VM groups compared with sham. Stereological analyses showed that similar to 70% of TV and VM cells differentiated into NeuN(+) neurons, with a high proportion of enkephalinergic and GABAergic cells in the TV group and enkephalinergic and serotoninergic cells in the VM group. Our study suggests that neuronal precursors from TV and VM, once implanted into the injured spinal cord, maturate into different neuronal subtypes, mainly GABAergic, serotoninergic, and enkephalinergic, and all subtypes alleviate pain, despite no significant motor recovery. The study was approved by the Animal Ethics Committee of the Medical School of the University of Sao Paulo (protocol number 033/14) on March 4, 2016.
- Neuroscience Knowledge and Endorsement of Neuromyths among Educators: What Is the Scenario in Brazil?(2022) SIMOES, Estefania; FOZ, Adriana; PETINATI, Fernanda; MARQUES, Alcione; SATO, Joao; LEPSKI, Guilherme; AREVALO, AnaliaThe field of neuroscience has seen significant growth and interest in recent decades. While neuroscience knowledge can benefit laypeople as well as professionals in many different areas, it may be particularly relevant for educators. With the right information, educators can apply neuroscience-based teaching strategies as well as protect themselves and their students against pseudoscientific ideas and products based on them. Despite rapidly growing sources of available information and courses, studies show that educators in many countries have poor knowledge of brain science and tend to endorse education-related neuromyths. Poor English skills and fewer resources (personal, institutional and governmental) may be additional limitations in Latin America. In order to better understand the scenario in Latin America's largest country, we created an anonymous online survey which was answered by 1634 individuals working in education from all five regions of Brazil. Respondents stated whether they agreed with each statement and reported their level of confidence for each answer. Significant differences in performance were observed across regions, between educators living in capital cities versus the outskirts, between those teaching in private versus public schools, and among educators teaching different levels (pre-school up to college/university). We also observed high endorsement of some key neuromyths, even among groups who performed better overall. To the best of our knowledge, this is the first study to conduct a detailed analysis of the profile of a large group of educators in Brazil. We discuss our findings in terms of efforts to better understand regional and global limitations and develop methods of addressing these most efficiently.
- MRI-Based Radiation-Free Method for Navigated Percutaneous Radiofrequency Trigeminal Rhizotomy(2015) LEPSKI, Guilherme; MESQUITA FILHO, Paulo Moacir; RAMINA, Kristofer; BISDAS, Sotirios; ERNEMANN, Ulrike; TATAGIBA, Marcos; MORGALLA, Matthias; FEIGL, GuentherBackground/Study Aims Percutaneous radiofrequency trigeminal rhizotomy (RTR) is a standardized treatment for trigeminal neuralgia, yet it has been associated with serious complications related to the cannulation of the foramen ovale. Some of these complications, such as carotid injury, are potentially lethal. Neuronavigation was recently proposed as a method to increase the procedure's safety. All of the techniques described so far rely on pre- or intraoperative computed tomography scanning. Here we present a simple method based on magnetic resonance imaging (MRI) (radiation free) used to target the foramen ovale under navigation guidance. Patients/Material and Methods We retrospectively analyzed nine patients who had undergone navigated percutaneous RTR based solely on preoperative MRI and compared them with 35 patients who underwent conventional RTR guided by fluoroscopy. We analyzed immediate and late outcome and categorized the results into pain free, > 70% pain reduction, and persistent pain. We also compared groups in terms of the duration of the procedure and the complication rates. Here we describe the navigation method in detail and review the anatomical landmarks for target definition. Results The duration of the surgical procedure was similar in both groups (32.1 in the standard technique versus 34.5 minutes with navigation; p = 0.5157). There was no significant difference between groups regarding pain reduction at the immediate (p = 1.0) or late follow-up (p = 0.6284) time points. Furthermore, no serious complications were observed in the navigated group. Conclusions We present a simple radiation-free method for neuronavigation-assisted percutaneous RTR. This method proved to be safe and effective, and it is especially recommended for young, inexperienced neurosurgeons.
- Characterization of traumatic spinal cord injury model in relation to neuropathic pain in the rat(2019) BATISTA, Chary Marquez; MARIANO, Eric Domingos; ONUCHIC, Fernando; DALE, Camila Squarzoni; SANTOS, Gustavo Bispo dos; CRISTANTE, Alexandre Fogaca; OTOCH, Jose Pinhata; TEIXEIR, Manoel Jacobsen; MORGALLA, Matthias; LEPSKI, GuilhermePurpose/aim: Neuropathic pain following spinal cord injury (SCI) has a tremendous impact on patient's quality of life, and frequently is the most limiting aspect of the disease. In view of the severity of this condition and the absence of effective treatments, the establishment of a reliable animal model that reproduces neuropathic pain after injury is crucial for a better understanding of the pathophysiology and for the development of new therapeutic strategies. Thus, the objective of the present study was to standardize the traumatic SCI model in relation to neuropathic pain.Materials and methods: Wistar rats were submitted to SCI of mild intensity (pendulum height 12.5mm) or moderate intensity (pendulum height 25mm) using the New York University Impactor equipment. Behavioural assessment was performed during 8weeks. Thereafter, spinal cords were processed for immunohistochemistry.Results: The animals of the moderate injury group in comparison with mild injury had a greater motor function deficit, worse mechanical allodynia, and latter bladder recovery; moreover, histological analysis revealed more extensive lesions with lower neuronal population.Conclusions: Our study suggests that moderate SCI causes a progressive and long-lasting painful condition (at least 8weeks), in addition to motor impairment, and thus represents a reliable animal model for the study of chronic neuropathic pain after SCI.
- Editorial: How to improve neuroscience education for the public and for a multi-professional audience in different parts of the globe(2022) AREVALO, Analia; ABUSAMRA, Valeria; LEPSKI, Guilherme
- Laser-evoked potentials recover gradually when using dorsal root ganglion stimulation, and this influences nociceptive pathways in neuropathic pain patients(2022) MORGALLA, Matthias Hubert; ZHANG, Yi; BARROS FILHO, Marcos Fortunato de; LEPSKI, Guilherme; CHANDER, Bankim SubhashObjective Dorsal root ganglion stimulation (DRGS) is able to relieve chronic neuropathic pain. There seems evidence that DRGS might achieve this by gradually influencing pain pathways. We used laser-evoked potentials (LEP) to verify our hypothesis that the recovery of the LEP may reflect DRGS-induced changes within the nociceptive system. Methods Nine patients (mean age 56.8 years, range 36-77 years, two females) diagnosed with chronic neuropathic pain in the knee or groin were enrolled in the study. We measured each patient's LEP at the painful limb and contralateral control limb on the first, fourth, and seventh day after implantation of the DRGS system. We used the numeric rating scale (NRS) for the simultaneous pain assessment. Results The LEP amplitude of the N2-P2 complex showed a significant increase on day 7 when compared to day 1 (Z = -2.666, p = 0.008) and to day 4 (Z = -2.547, p = 0.011), respectively. There was no significant difference in the N2-P2 complex amplitude between ON and OFF states during DRGS. The patients' NRS significantly decreased after 1 day (p = 0.007), 4 days (p = 0.007), and 7 days (p = 0.007) when compared to the baseline. Conclusions The results show that with DRGS, the LEP recovered gradually within 7 days in neuropathic pain patients. Therefore, reduction of the NRS in patients with chronic neuropathic pain might be due to DRGS-induced processes within the nociceptive system. These processes might indicate neuroplasticity mediated recovery of the LEP.
- 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.
- Electrophysiological predictors of hearing deterioration based on AEP monitoring during petroclival meningioma resection(2021) LEPSKI, Guilherme; AREVALO, Analia; ROSER, Florian; LIEBSCH, M.; TATAGIBA, MarcosThe objective of this study was to calculate the risk of postsurgical hearing deterioration as a function of changes in the amplitude and latency of the most stable components (waves III and V) of the auditory evoked potential (AEP) during petroclival meningioma resection surgery. We retrospectively analyzed intraoperative AEP monitoring results and pre- and postsurgical hearing status in 40 consecutive patients who were surgically treated for petroclival meningiomas. Statistical analyses were conducted to identify the most sensitive and specific way to predict hearing dysfunction after surgery. Patients' mean age was 59 +/- 10 years, and 31 (77.5%) were women. Twelve (30%) patients presented with clinically detectable hearing impairment preoperatively. At the first postoperative assessment, four of those 12 patients reported subjective improvement, and eight reported hearing deterioration. Of those eight, four remained stable and four recovered hearing by the last assessment. Wave III latency reached its highest specificity (100%) and sensitivity (71.43%) atx = 143%. Wave V latency, on the other hand, reached its highest sensitivity (71%) and specificity (93%) atx = 124%. Finally, wave V amplitude reached its highest sensitivity (100%) and specificity (79%) atx = 74%. Intraoperative alterations of wave III latency and wave V amplitude seem to be highly sensitive and specific at predicting the risk of auditory dysfunction in patients undergoing petroclival meningioma resection and should be used to determine maximum resection with preservation of function.
- 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.
- Everything old is new again. revisiting hypophysectomy for the treatment of refractory cancer-related pain: a systematic review(2024) ALMEIDA, Timoteo; MONACO, Bernardo A.; VASCONCELOS, Fernando; PIEDADE, Guilherme S.; MORELL, Alexis; OGOBUIRO, Ifeanyichukwu; LEPSKI, Guilherme A.; FURLANETTI, Luciano L.; CORDEIRO, Karina K.; BENJAMIN, Carolina; JAGID, Jonathan R.; CORDEIRO, Joacir G.Cancer-related pain is a common and debilitating condition that can significantly affect the quality of life of patients. Opioids, NSAIDs, and antidepressants are among the first-line therapies, but their efficacy is limited or their use can be restricted due to serious side effects. Neuromodulation and lesioning techniques have also proven to be a valuable instrument for managing refractory pain. For patients who have exhausted all standard treatment options, hypophysectomy may be an effective alternative treatment. We conducted a comprehensive systematic review of the available literature on PubMed and Scielo databases on using hypophysectomy to treat refractory cancer-related pain. Data extraction from included studies included study design, treatment model, number of treated patients, sex, age, Karnofsky Performance Status (KPS) score, primary cancer site, lead time from diagnosis to treatment, alcohol injection volume, treatment data, and clinical outcomes. Statistical analysis was reported using counts (N, %) and means (range). The study included data from 735 patients from 24 papers treated with hypophysectomy for refractory cancer-related pain. 329 cancer-related pain patients were treated with NALP, 216 with TSS, 66 with RF, 55 with Y90 brachytherapy, 51 with Gamma Knife radiosurgery (GK), and 18 with cryoablation. The median age was 58.5 years. The average follow-up time was 8.97 months. Good pain relief was observed in 557 out of 735 patients, with complete pain relief in 108 out of 268 patients. Pain improvement onset was observed 24 h after TSS, a few days after NALP or cryoablation, and a few days to 4 weeks after GK. Complications varied among treatment modalities, with diabetes insipidus (DI) being the most common complication. Although mostly forgotten in modern neurosurgical practice, hypophysectomy is an attractive option for treating refractory cancer-related pain after failure of traditional therapies. Radiosurgery is a promising treatment modality due to its high success rate and reduced risk of complications.