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
54 resultados
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- 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.
- 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
- 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.
bookPart Tumores do Sistema Nervoso Central(2016) SOUSA JUNIOR, Leonardo de Moura; LEPSKI, Guilherme Alves- Neurosurgery(2022) LEPSKI, G. A.; NEPOMUCENO, T. B.The oncological treatment of intracranial tumors demands an experienced and multidisciplinary team able to manage vascular complications and perform reconstructive procedures when needed. Some brain tumors dislocate, enclose, and sometimes invade major arterial and venous structures of the brain, which if sacrificed may lead to unacceptable neurological deficits. Since the brain tumor treatment is a balance between preserving function and removing the greatest amount of tumor possible, the oncological neurosurgeon must also be trained to perform arterial and venous reconstruction and bypasses. In the present chapter, we address reconstructive strategies in the arterial and venous systems to preserve brain hemodynamics, either in the elective or emergent conditions. Brain tumors increase the risk of venous thromboembolism, which complicates the decision as to when to start anticoagulation (either before or after brain surgery). In addition, postoperative bleeding is a major complication, potentially culminating in death or serious neurological deficits. Nevertheless, many studies have demonstrated that thromboembolism risk overcomes the risk of postoperative bleeding in the neurosurgical oncology cohort, so that most protocols recommend early prophylaxis. This does not preclude the need for multifactorial and individual-based decision-making, paying careful attention to patient- and surgery-related risks. © Springer Nature Switzerland AG 2022.
- 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.