Lateral fluid percussion injury: A rat model of experimental traumatic brain injury.

Traumatic brain injury (TBI) represents one of the leading causes of disability and death worldwide. The annual economic impact of TBI-including direct and indirect costs-is high, particularly impacting low- and middle-income countries. Despite extensive research, a comprehensive understanding of the primary and secondary TBI pathophysiology, followed by the development of promising therapeutic approaches, remains limited. These fundamental caveats in knowledge have motivated the development of various experimental models to explore the molecular mechanisms underpinning the pathogenesis of TBI. In this context, the Lateral Fluid Percussion Injury (LFPI) model produces a brain injury that mimics most of the neurological and systemic aspects observed in human TBI. Moreover, its high reproducibility makes the LFPI model one of the most widely used rodent-based TBI models. In this chapter, we provide a detailed surgical protocol of the LFPI model used to induce TBI in adult Wistar rats. We further highlight the neuroscore test as a valuable tool for the evaluation of TBI-induced sensorimotor consequences and their severity in rats. Lastly, we briefly summarize the current knowledge on the pathological aspects and functional outcomes observed in the LFPI-induced TBI model in rodents.

Motor, Cognitive, and Behavioral Impairment in TLR3 and TLR9 Deficient Male Mice: Insights into the Non-Immunological Roles of Toll-Like Receptors.

BACKGROUND: Toll-like receptors (TLRs) play a critical role in initiating the innate immune response to infection or injury. Recent studies have uncovered their intriguing functions as moonlighting proteins involved in various biological processes, including development, learning, and memory. However, the specific functions of individual TLRs are still largely unknown. AIMS: We investigated the effects of TLR3 and TLR9 receptor deficiency on motor, cognitive, and behavioral functions during development using genetically modified male mice of different ages. METHODS: We evaluated the motor coordination, anxiety-like behavior, spatial learning, and working memory of male mice lacking the TLR3 and TLR9 genes at different ages (two, four, six, and eight months) using the rotarod, open field, water maze, and T-maze tests. RESULTS: We observed that the deletion of either TLR3 or TLR9 resulted in impaired motor performance. Furthermore, young TLR3-deficient mice exhibited reduced anxiety-like behavior and spatial learning deficits; however, their working memory was unaffected. In contrast, young TLR9-knockout mice showed hyperactivity and a tendency toward decreased working memory. CONCLUSIONS: These findings provide valuable insights into the broader roles of the TLR system beyond the innate immune response, revealing its involvement in pathways associated with the central nervous system. Importantly, our results establish a strong association between the endosomal receptors TLR3 and TLR9 and the performance of motor, cognitive, and behavioral tasks that change over time. This study contributes to the growing body of research on the multifaceted functions of TLRs and enhances our understanding of their participation in non-immune-related processes.

Human Embryonic Stem Cell-Derived Immature Midbrain Dopaminergic Neurons Transplanted in Parkinsonian Monkeys.

Human embryonic stem cells (hESCs) differentiate into specialized cells, including midbrain dopaminergic neurons (DANs), and Non-human primates (NHPs) injected with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine develop some alterations observed in Parkinson's disease (PD) patients. Here, we obtained well-characterized DANs from hESCs and transplanted them into two parkinsonian monkeys to assess their behavioral and imaging changes. DANs from hESCs expressed dopaminergic markers, generated action potentials, and released dopamine (DA) in vitro. These neurons were transplanted bilaterally into the putamen of parkinsonian NHPs, and using magnetic resonance imaging techniques, we calculated the fractional anisotropy (FA) and mean diffusivity (MD), both employed for the first time for these purposes, to detect in vivo axonal and cellular density changes in the brain. Likewise, positron-emission tomography scans were performed to evaluate grafted DANs. Histological analyses identified grafted DANs, which were quantified stereologically. After grafting, animals showed signs of partially improved motor behavior in some of the HALLWAY motor tasks. Improvement in motor evaluations was inversely correlated with increases in bilateral FA. MD did not correlate with behavior but presented a negative correlation with FA. We also found higher 11C-DTBZ binding in positron-emission tomography scans associated with grafts. Higher DA levels measured by microdialysis after stimulation with a high-potassium solution or amphetamine were present in grafted animals after ten months, which has not been previously reported. Postmortem analysis of NHP brains showed that transplanted DANs survived in the putamen long-term, without developing tumors, in immunosuppressed animals. Although these results need to be confirmed with larger groups of NHPs, our molecular, behavioral, biochemical, and imaging findings support the integration and survival of human DANs in this pre-clinical PD model.

Cannabidiol Modifies the Glutamate Over-Release in Brain Tissue of Patients and Rats with Epilepsy: A Pilot Study.

Drug-resistant epilepsy (DRE) is associated with high extracellular levels of glutamate. Studies support the idea that cannabidiol (CBD) decreases glutamate over-release. This study focused on investigating whether CBD reduces the evoked glutamate release in cortical synaptic terminals obtained from patients with DRE as well as in a preclinical model of epilepsy. Synaptic terminals (synaptosomes) were obtained from the epileptic neocortex of patients with drug-resistant temporal lobe epilepsy (DR-TLE, n = 10) or drug-resistant extratemporal lobe epilepsy (DR-ETLE, n = 10) submitted to epilepsy surgery. Synaptosomes highly purified by Percoll-sucrose density gradient were characterized by confocal microscopy and Western blot. Synaptosomes were used to estimate the high KCl (33 mM)-evoked glutamate release in the presence of CBD at different concentrations. Our results revealed responsive tissue obtained from seven patients with DR-TLE and seven patients with DR-ETLE. Responsive tissue showed lower glutamate release (p < 0.05) when incubated with CBD at low concentrations (less than 100 µM) but not at higher concentrations. Tissue that was non-responsive to CBD (DR-TLE, n = 3 and DR-ELTE, n = 3) showed high glutamate release despite CBD exposure at different concentrations. Simultaneously, a block of the human epileptic neocortex was used to determine its viability through whole-cell and extracellular electrophysiological recordings. The electrophysiological evaluations supported that the responsive and non-responsive human epileptic neocortices used in the present study exhibited proper neuronal viability and stability to acquire electrophysiological responses. We also investigated whether the subchronic administration of CBD could reduce glutamate over-release in a preclinical model of temporal lobe epilepsy. Administration of CBD (200 mg/kg, p.o. every 24 h for 7 days) to rats with lithium-pilocarpine-evoked spontaneous recurrent seizures reduced glutamate over-release in the hippocampus. The present study revealed that acute exposure to low concentrations of CBD can reduce the glutamate over-release in synaptic terminals obtained from some patients with DRE. This effect is also evident when applied subchronically in rats with spontaneous recurrent seizures. An important finding was the identification of a group of patients that were non-responsive to CBD effects. Future studies are essential to identify biomarkers of responsiveness to CBD to control DRE.

Revisiting the concept of drug-resistant epilepsy: A TASK1 report of the ILAE/AES Joint Translational Task Force.

Despite progress in the development of anti-seizure medications (ASMs), one third of people with epilepsy have drug-resistant epilepsy (DRE). The working definition of DRE, proposed by the International League Against Epilepsy (ILAE) in 2010, helped identify individuals who might benefit from presurgical evaluation early on. As the incidence of DRE remains high, the TASK1 workgroup on DRE of the ILAE/American Epilepsy Society (AES) Joint Translational Task Force discussed the heterogeneity and complexity of its presentation and mechanisms, the confounders in drawing mechanistic insights when testing treatment responses, and barriers in modeling DRE across the lifespan and translating across species. We propose that it is necessary to revisit the current definition of DRE, in order to transform the preclinical and clinical research of mechanisms and biomarkers, to identify novel, effective, precise, pharmacologic treatments, allowing for earlier recognition of drug resistance and individualized therapies.

Transcranial Focal Electric Stimulation Avoids P-Glycoprotein Over-Expression during Electrical Amygdala Kindling and Delays Epileptogenesis in Rats.

Recent evidence suggests that P-glycoprotein (P-gp) overexpression mediates hyperexcitability and is associated with epileptogenesis. Transcranial focal electrical stimulation (TFS) delays epileptogenesis and inhibits P-gp overexpression after a generalized seizure. Here, first we measured P-gp expression during epileptogenesis and second, we assessed if TFS antiepileptogenic effect was related with P-gp overexpression avoidance. Male Wistar rats were implanted in right basolateral amygdala and stimulated daily for electrical amygdala kindling (EAK), P-gp expression was assessed during epileptogenesis in relevant brain areas. Stage I group showed 85% increase in P-gp in ipsilateral hippocampus (p < 0.001). Stage III group presented 58% and 57% increase in P-gp in both hippocampi (p < 0.05). Kindled group had 92% and 90% increase in P-gp in both hippocampi (p < 0.01), and 93% and 143% increase in both neocortices (p < 0.01). For the second experiment, TFS was administrated daily after each EAK stimulation for 20 days and P-gp concentration was assessed. No changes were found in the TFS group (p > 0.05). Kindled group showed 132% and 138% increase in P-gp in both hippocampi (p < 0.001) and 51% and 92% increase in both cortices (p < 0.001). Kindled + TFS group presented no changes (p > 0.05). Our experiments revealed that progression of EAK is associated with increased P-gp expression. These changes are structure-specific and dependent on seizure severity. EAK-induced P-gp overexpression would be associated with neuronal hyperexcitability and thus, epileptogenesis. P-gp could be a novel therapeutical target to avoid epileptogenesis. In accordance with this, TFS inhibited P-gp overexpression and interfered with EAK. An important limitation of the present study is that P-gp neuronal expression was not evaluated under the different experimental conditions. Future studies should be carried out to determine P-gp neuronal overexpression in hyperexcitable networks during epileptogenesis. The TFS-induced lessening of P-gp overexpression could be a novel therapeutical strategy to avoid epileptogenesis in high-risk patients.

A simple and inexpensive method to monitor and minimize exposure from manipulation of cytotoxic drugs.

Pharmacy personnel that manipulate cytotoxic drugs are under continuous exposure risk. Therefore, training and strict adherence to recommended practices should always be promoted. The main objective of this study was to develop and apply a safe, effective and low-cost method for the training and assessment of the safe handling of cytotoxic drugs, using commercially available tonic water. To evaluate the potential of tonic water as a replacement marker for quinine hydrochloride, deliberate spills of 1 mL of four different tonic waters (one coloured and three non-coloured) were analysed under ultraviolet light (300-400 nm). The pigmented sample did not produce fluorescence under ultraviolet (UV) light. The three commercially available tonic waters that exhibited fluorescence were further analysed by UV/Vis spectrophotometry (300-500 nm). Afterwards, a protocol of simulated manipulation of cytotoxic drugs was developed and applied to 12 pharmacy technicians, that prepared 24 intravenous bags according to recommended routine procedures using tonic water. Participants responded to a brief questionnaire to evaluate the adequacy and applicability of the activity. Seven of the participants had spillages during manipulation, the majority of which recorded during manipulation with needles. All participants scored the tonic water manipulation simulation with 4 or 5 points for simplicity, efficiency and feasibility. The obtained results suggest that tonic water can be used to simulate the manipulation of cytotoxic drugs in training and assessment programs. By using this replacement marker for quinine hydrochloride, it is possible to perform a more cost-effective, yet equally effective, assessment.

Hydrogen sulfide prevents the vascular dysfunction induced by severe traumatic brain injury in rats by reducing reactive oxygen species and modulating eNOS and H2S-synthesizing enzyme expression.

AIM: To assess the effects of subchronic administration with NaHS, an exogenous H2S donor, on TBI-induced hypertension and vascular impairments. MAIN METHODS: Animals underweministration does not prevent the body weight loss but slightly imnt a lateral fluid percussion injury, and the hemodynamic variables were measured in vivo by plethysmograph method. The vascular function in vitro, the ROS levels by the DCFH-DA method and the expression of H2S-synthesizing enzymes and eNOS by Western blot were measured in isolated thoracic aortas at day 7 post-TBI. The effect of L-NAME on NaHS-induced effects in vascular function was evaluated. Brain water content was determined 7 days after trauma induction. Body weight was recorded throughout the experimental protocol, whereas the sensorimotor function was evaluated using the neuroscore test at days -1 (basal), 2, and 7 after the TBI induction. KEY FINDINGS: TBI animals showed: 1) an increase in hemodynamic variables and ROS levels in aortas; 2) vascular dysfunction; 3) sensorimotor dysfunction; and 4) a decrease in body weight, the expression of H2S-synthesizing enzymes, and eNOS phosphorylation. Interestingly, NaHS subchronic administration (3.1 mg/kg; i.p.; every 24 h for six days) prevented the development of hypertension, vascular dysfunction, and oxidative stress. L-NAME abolished NaHS-induced effects. Furthermore, NaHS treatment restored H2S-synthesizing enzymes and eNOS phosphorylation with no effect on body weight, sensorimotor impairments, or brain water content. SIGNIFICANCE: Taken together, these results demonstrate that H2S prevents TBI-induced hypertension by restoring vascular function and modulating ROS levels, H2S-synthesizing enzymes expression, and eNOS phosphorylation.

Targeting hydrogen sulfide and nitric oxide to repair cardiovascular injury after trauma.

The systemic cardiovascular effects of major trauma, especially neurotrauma, contribute to death and permanent disability in trauma patients and treatments are needed to improve outcomes. In some trauma patients, dysfunction of the autonomic nervous system produces a state of adrenergic overstimulation, causing either a sustained elevation in catecholamines (sympathetic storm) or oscillating bursts of paroxysmal sympathetic hyperactivity. Trauma can also activate innate immune responses that release cytokines and damage-associated molecular patterns into the circulation. This combination of altered autonomic nervous system function and widespread systemic inflammation produces secondary cardiovascular injury, including hypertension, damage to cardiac tissue, vascular endothelial dysfunction, coagulopathy and multiorgan failure. The gasotransmitters nitric oxide (NO) and hydrogen sulfide (H2S) are small gaseous molecules with potent effects on vascular tone regulation. Exogenous NO (inhaled) has potential therapeutic benefit in cardio-cerebrovascular diseases, but limited data suggests potential efficacy in traumatic brain injury (TBI). H2S is a modulator of NO signaling and autonomic nervous system function that has also been used as a drug for cardio-cerebrovascular diseases. The inhaled gases NO and H2S are potential treatments to restore cardio-cerebrovascular function in the post-trauma period.

Cannabidiol Reduces Short- and Long-Term High Glutamate Release after Severe Traumatic Brain Injury and Improves Functional Recovery.

This study aimed to determine if orally administered cannabidiol (CBD) lessens the cortical over-release of glutamate induced by a severe traumatic brain injury (TBI) and facilitates functional recovery. The short-term experiment focused on identifying the optimal oral pretreatment of CBD. Male Wistar rats were pretreated with oral administration of CBD (50, 100, or 200 mg/kg) daily for 7 days. Then, extracellular glutamate concentration was estimated by cortical microdialysis before and immediately after a severe TBI. The long-term experiment focused on evaluating the effect of the optimal treatment of CBD (pre- vs. pre- and post-TBI) 30 days after trauma. Sensorimotor function, body weight, and mortality rate were evaluated. In the short term, TBI induced a high release of glutamate (738% ± 173%; p < 0.001 vs. basal). Oral pretreatment with CBD at all doses tested reduced glutamate concentration but with higher potency at when animals received 100 mg/kg (222 ± 33%, p < 0.01 vs. TBI), an effect associated with a lower mortality rate (22%, p < 0.001 vs. TBI). In the long-term experiment, the TBI group showed a high glutamate concentration (149% p < 0.01 vs. SHAM). In contrast, animals receiving the optimal treatment of CBD (pre- and pre/post-TBI) showed glutamate concentrations like the SHAM group (p > 0.05). This effect was associated with high sensorimotor function improvement. CBD pretreatment, but not pre-/post-treatment, induced a higher body weight gain (39% ± 2.7%, p < 0.01 vs. TBI) and lower mortality rate (22%, p < 0.01 vs. TBI). These results support that orally administered CBD reduces short- and long-term TBI-induced excitotoxicity and facilitated functional recovery. Indeed, pretreatment with CBD was sufficient to lessen the adverse sequelae of TBI.

New interaction modalities between the pharmaceutical industry and physicians.

Due to sanitary restrictions secondary to the COVID-19 pandemic, various interactions between the pharmaceutical industry and physicians have changed. One of them has been the method for promoting medicinal products through academic meetings around diseases of financial interest. A recent modality has been unilateral promotion by the pharmaceutical industry through academic events with the invitation of so-called "experts" for the promotion of a specific drug. These meetings are often biased not towards optimal care of a disease, but rather towards commercial promotion of a specific drug, which may or may not be the best option, without considering associated therapeutic alternatives. The Committee of Ethics and Transparency in the Physician-Industry Relationship, of the National Academy of Medicine, analyzes this new circumstance and proposes some considerations to the medical community.

Debido a las restricciones sanitarias secundarias a la pandemia de COVID-19, diversas interacciones entre la industria farmacéutica y los médicos cambiaron. Una de ellas ha sido el método promocional de medicamentos a través de reuniones académicas en torno a padecimientos de interés financiero. Una modalidad reciente ha sido la promoción unilateral de un fármaco determinado por parte de la industria farmacéutica por medio de eventos académicos con la invitación de aparentes "expertos". Estas reuniones frecuentemente están sesgadas no hacia la atención óptima de un padecimiento, sino a la promoción comercial de un medicamento específico que pudiera o no ser la mejor opción o sin la consideración de alternativas terapéuticas asociadas. El Comité de Ética y Transparencia en la Relación Médico-Industria, de la Academia Nacional de Medicina de México, analiza esta nueva circunstancia y propone algunas consideraciones a la comunidad médica.

Programa Mais Médicos na Bahia e o impacto no diagnóstico precoce do IAM: relato de experiência / Mais Médicos Program in Bahia and the impact on early diagnosis of IAM: an experience report / Programa Más Médicos en Bahía y su impacto en el diagnóstico precoz del IAM: informe de experiencia

Capaz de resolver cerca de 80% de todas as necessidades em saúde, a Atenção Primária se tornou uma das principais e mais eficientes estratégias do Sistema Único de Saúde. Diante da histórica carência e má distribuição do profissional médico no Brasil, o Programa Mais Médicos viabilizou o provimento do profissional nas localidades mais longínquas. Em parceria com o Programa Nacional Telessaúde Brasil Redes, o diagnóstico pode chegar em todos os lugares do país, possibilitando assistência e controle das patologias de maior morbimortalidade. Um exemplo é o infarto agudo do miocárdio, no qual "tempo é vida", pois, para cada dez minutos de retardo na instituição da terapia de reperfusão, reduz-se a expectativa de vida do paciente em 120 dias. O objetivo deste trabalho é demonstrar uma experiência exitosa que envolveu a articulação resolutiva da rede pública de saúde a partir da Atenção Primária e do Programa Mais Médicos. Trata-se de um estudo descritivo, qualitativo, no qual se buscou descrever a pronta assistência a um paciente com infarto agudo do miocárdio em uma zona rural. O resultado mostrou que uma Atenção Básica resolutiva e integrada aos demais níveis de assistência é possível, permitindo que o paciente infartado seja beneficiado a tempo pela reperfusão miocárdica e impactando de forma positiva seu prognóstico e qualidade de vida. A experiência forneceu estímulo para busca contínua de superação e enfrentamento dos desafios, assim como do aperfeiçoamento da gestão pública da saúde.

Capable of solving nearly 80% of all health needs, Primary Care has become one of the main and most efficient strategies in the Unified Health System. Given the historic shortage and poor distribution of medical professionals in Brazil, the Mais Médicos Program made it possible to provide professionals in remote locations. In partnership with the National Telehealth Brazil Networks Program, diagnosis can reach all parts of Brazil, enabling treatment and control of pathologies with greater morbidity and mortality. One example is acute myocardial infarction, in which "time is life," because for every 10-minute delay in instituting reperfusion therapy, life expectancy is reduced by 120 days. Given this scenario, this paper reports on a successful experience that involved the resolutive articulation of the public health network from Primary Care and the More Doctors Program. This descriptive and qualitative study describes the prompt care of a patient with acute myocardial infarction in a rural area. Results shows that a resolutive Primary Care integrated with other levels of care is possible, allowing the infarcted patient to benefit in time from myocardial reperfusion and positively impacting their prognosis and quality of life. The experience encouraged continuous search to overcome and face the challenges, as well as to improve public health management.

Con la capacidad de resolución de cerca del 80% de todas las necesidades de salud, la Atención Primaria se ha convertido en una de las principales y más eficientes estrategias del Sistema Único de Salud. En vista de la escasez estructural histórica y la mala distribución de los profesionales médicos en Brasil, el Programa Más Médicos hizo posible la provisión de profesionales a lugares más distantes. En una alianza con el Programa Redes Nacionales de Telesalud Brasil, el diagnóstico puede llegar a todos los lugares del país, posibilitando la asistencia y el control de patologías con mayor morbimortalidad. Un ejemplo es el infarto agudo de miocardio, en el que "el tiempo es vida", pues por cada 10 minutos de retraso en la instauración de la terapia de reperfusión, la esperanza de vida se reduce en 120 días. El objetivo de este trabajo es evidenciar una experiencia exitosa que involucró la articulación resolutiva de la red pública de salud con base en la Atención Primaria y el Programa Más Médicos. Se trata de un estudio cualitativo, descriptivo, que buscó describir la atención oportuna de un paciente con infarto agudo de miocardio en una zona rural. El resultado mostró que es posible una Atención Primaria resolutiva e integrada con los demás niveles asistenciales, que permita que el paciente infartado sea beneficiado a tiempo por la reperfusión miocárdica, lo que impacta positivamente en su pronóstico y calidad de vida. La experiencia sirvió de estímulo para la búsqueda continua de superación y enfrentamiento de los desafíos, así como de la mejora de la gestión en salud pública.

Exogenous hydrogen sulfide restores CSE and CBS but no 3-MST protein expression in the hypothalamus and brainstem after severe traumatic brain injury.

Hydrogen sulfide (H2S) is a gasotransmitter endogenously synthesized by cystathionine-γ-lyase (CSE), cystathionine-ß-synthase (CBS), and 3-mercaptopiruvate sulfurtransferase (3-MST) enzymes. H2S exogenous administration prevents the development of hemodynamic impairments after traumatic brain injury (TBI). Since the hypothalamus and the brainstem highly regulate the cardiovascular system, this study aimed to evaluate the effect of NaHS subchronic treatment on the changes of H2S-sythesizing enzymes in those brain areas after TBI and in physiological conditions. For that purpose, animals were submitted to a lateral fluid percussion injury, and the changes in CBS, CSE, and 3-MST protein expression were measured by western blot at days 1, 2, 3, 7, and 28 in the vehicle group, and 7 and 28 days after NaHS treatment. After severe TBI induction, we found a decrease in CBS and CSE protein expression in the hypothalamus and brainstem; meanwhile, 3-MST protein expression diminished only in the hypothalamus compared to the Sham group. Remarkably, i.p. daily injections of NaHS, an H2S donor, (3.1 mg/kg) during seven days: (1) restored CBS and CSE but no 3-MST protein expression in the hypothalamus at day 28 post-TBI; (2) reestablished only CSE in brainstem 7 and 28 days after TBI; and (3) did not modify H2S-sythesizing enzymes protein expression in uninjured animals. Mainly, our results show that the NaHS effect on CBS and CSE protein expression is observed in a time- and tissue-dependent manner with no effect on 3-MST expression, which may suggest a potential role of H2S synthesis in hypothalamus and brainstem impairments observed after TBI.

Nuevas modalidades de interacción entre la industria farmacéutica y los médicos / New interaction modalities between the pharmaceutical industry and physicians

Resumen Debido a las restricciones sanitarias secundarias a la pandemia de COVID-19, diversas interacciones entre la industria farmacéutica y los médicos cambiaron. Una de ellas ha sido el método promocional de medicamentos a través de reuniones académicas en torno a padecimientos de interés financiero. Una modalidad reciente ha sido la promoción unilateral de un fármaco determinado por parte de la industria farmacéutica por medio de eventos académicos con la invitación de aparentes "expertos". Estas reuniones frecuentemente están sesgadas no hacia la atención óptima de un padecimiento, sino a la promoción comercial de un medicamento específico que pudiera o no ser la mejor opción o sin la consideración de alternativas terapéuticas asociadas. El Comité de Ética y Transparencia en la Relación Médico-Industria, de la Academia Nacional de Medicina de México, analiza esta nueva circunstancia y propone algunas consideraciones a la comunidad médica.

Abstract Due to sanitary restrictions secondary to the COVID-19 pandemic, various interactions between the pharmaceutical industry and physicians have changed. One of them has been the method for promoting medicinal products through academic meetings around diseases of financial interest. A recent modality has been unilateral promotion by the pharmaceutical industry through academic events with the invitation of so-called "experts" for the promotion of a specific drug; these meetings are often biased not towards optimal care of a disease, but rather towards commercial promotion of a specific drug, which may or may not be the best option, without considering associated therapeutic alternatives. The Committee of Ethics and Transparency in the Physician-Industry Relationship, of the National Academy of Medicine, analyzes this new circumstance and proposes some considerations to the medical community.

Protein expression of P-glycoprotein in neocortex from patients with frontal lobe epilepsy.

Frontal lobe epilepsy (FLE) is the second most frequent type of epilepsy and the surgical outcome depends on the etiology. For instance, patients with posttraumatic FLE (PTE) have a worse surgical outcome compared to patients with FLE related to a tumoral lesion (TL). The present study focuses to determine if the FLE etiology is associated with the P-glycoprotein (P-gp) expression, a condition associated with drug resistance. P-gp expression and cellular localization were determined by Western Blot and immunohistochemical experiments in cortical brain samples obtained from patients with PTE (n = 5), TL (n = 5), and autopsies (n = 5). The neuronal count was estimated by Nissl and stereology procedure. Results showed that the autopsies tissue showed a neuronal count of 3514 ± 304.2 neurons per mm3. The P-gp expression ratio was 0.33 ± 0.02. Its expression was found in endothelial cells. Negligible P-gp expression was detected in neurons and astrocytes. Compared to the autopsies group, the TL group showed no changes in the neuronal count but, there was a decreased P-gp expression ratio (46%, p < 0.05). P-gp was located mainly in neurons, slight in astroglial, and endothelial cells. The PTE group showed a similar P-gp expression ratio compared to the autopsies group. P-gp was expressed in neurons, astrocytes, and endothelial cells in these samples. However, experiments revealed a high P-gp expression in a lower neuronal count (38%, p < 0.05 vs autopsy group). The present study reveals that patients with PTE present neuronal P-gp overexpression. This finding could underlie their worst surgical outcome.

A rare cause of chest pain in paediatric age: a teenager with acute myocardial infarction due to spontaneous coronary artery dissection.

A healthy 17-year-old boy was admitted to the emergency department presenting with a pressure-like sternal pain that started during exercise. His physical examination was normal. Twelve-lead ECG and transthoracic echocardiogram suggested a myocardial infarction. The patient was submitted to an invasive coronary angiography, which revealed a distal occlusion of the left anterior descending artery, due to a spontaneous coronary artery dissection. A balloon angioplasty was performed, with good results. Aetiological study did not discover any pathologic condition. Chest pain in paediatric age is a frequent complaint, despite not being usually caused by a serious condition. However, it is important to remember warning signs in order to diagnose life-threatening diseases, as soon as possible.

Introduction to the special issue "Redesigning the hypotheses for drug-resistant epilepsy".

Drug-resistant epilepsy represents an important neurological condition. Its prevalence is not modified in spite of the different hypotheses established to understand the mechanisms involved. The special issue "Redesigning the hypotheses for drug-resistant epilepsy" represents an effort of different investigators to discuss the limitations of the hypotheses that explain the drug resistance in epilepsy. In addition, new paradigms and novel strategies to control drug-resistant epilepsy are pointed out to understand this condition.

Targeting Endocannabinoid System in Epilepsy: For Good or for Bad.

Epilepsy is a neurological disorder with a high prevalence worldwide. Several studies carried out during the last decades indicate that the administration of cannabinoids as well as the activation of the endocannabinoid system (ECS) represent a therapeutic strategy to control epilepsy. However, there are controversial studies indicating that activation of ECS results in cell damage, inflammation and neurotoxicity, conditions that facilitate the seizure activity. The present review is focused to present findings supporting this issue. According to the current discrepancies, it is relevant to elucidate the different effects induced by the activation of ECS and determine the conditions under which it facilitates the seizure activity.