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BACKGROUND: Mexico is under-represented in global neurosurgical research. High-income countries represent roughly 10% of the world's population but utilize about 90% of the research funding for medical research, highlighting the need for promoting research initiatives in low- and middle-income countries. We present an online-based research initiative in Mexico that aims to reduce the research gap in neurosurgery. METHODS: Implemented in early 2023, our online-based research initiative included weekly modules covering study types, statistical analysis, meta-analysis, and scientific writing. The first cohort of 22 students completed the 12-week program and then served as tutors for subsequent cohorts. The research model was promoted via word of mouth and social media platforms to medical students, graduates, and specialists across Latin America. Post-program, tutors and the author conducted weekly planning sessions to assist with project planning, analysis, and article writing. RESULTS: From 833 registrations, over 800 students completed at least 1 training module. The program published 7 articles and presented 12 abstracts at major international neurosurgical meetings. We performed a bibliographic analysis in PubMed and found that from 2021 to 2022, 33,637 neurosurgical articles were published, with 197 involving collaboration from Mexico (0.5%). From 2023 to 2024, 24,121 articles were published, with 205 involving collaboration from Mexico (0.8%), a significant increase (P < 0.001). Our collaboration contributed to 3.4% of these, representing a significant addition in 2023-2024 (P = 0.026). CONCLUSIONS: This online-based neurosurgical model contributed to 3.4% of the neurosurgical research productivity in Mexico. Our findings suggest that this model can effectively bridge the research gap and enhance scientific contributions in developing countries.

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BACKGROUND: Pituitary apoplexy (PA) is characterized by acute hemorrhage or infarction of the pituitary gland. Management can be either conservative or surgical. Evidence favoring either is still limited to observational studies. This meta-analysis evaluates the effectiveness of both approaches on patient outcomes. METHODS: A systematic search was performed until February 2024. We included cohort studies of patients with PA. Patients were divided into 2 groups: a conservative management group and a surgery group, including early and late surgery. Outcomes of interest were assessed categorically using risk ratio (RR) and Mantel-Haenszel's random effects model. RESULTS: Of the 273 published articles, 15 cohort studies comprising 908 patients were included. There was no statistically significant difference between groups in recovery of ophthalmoplegia (RR=1.09, confidence interval [CI]=1.00-1.18, P=0.05), visual field (RR=1.09, CI=0.91-1.3, P=0.35), visual acuity (RR=1.05, CI=0.87-1.26, P=0.61), hypopituitarism (RR=1.37, CI=0.81-2.32, P=0.25), and tumor recurrence (RR=0.74, CI=0.34-1.61, P=0.45). This was similar for conservative management versus early surgery in recovery of visual field (RR=0.92, CI=0.62-1.37, P=0.68), visual acuity (RR=1.01, CI=0.81-1.26, P=0.93), and ophthalmoplegia (RR=0.92, CI=0.53-1.61, P=0.77). CONCLUSIONS: Both interventions provide comparable outcomes. These findings, though, are drawn from observational studies, and more severe cases typically undergo surgery. Larger studies are necessary to provide conclusive evidence.

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BACKGROUND: Most of the scientific and healthcare resources in Mexico are limited to the large major cities. However, many communities with complex socioeconomic and cultural backgrounds have limited access to neurosurgical care. A cross-sectional study aiming to evaluate the population's perception regarding neurosurgical care was conducted. METHODS: A nationwide online survey, conducted starting February 2023, assessed public perception of neurosurgical care. Data analysis was performed based on sociodemographic characteristics such as age, socioeconomic status, religion, and education. Pearson's chi-square and odds ratio were employed for statistical comparisons of categorical variables. RESULTS: A total of 508 participants consented to the survey. Younger participants and higher education levels correlated with greater perceived knowledge about neurosurgery (P = <0.001) and higher confidence in neurosurgical healthcare personnel (P = 0.021 and P = 0.022, respectively). Lower educational levels were prone to perceive neurosurgical care as less safe and effective (P = 0.002) and preferred to seek initial alternative/traditional treatments for neurosurgical issues (P = 0.012). A higher income level was associated with a preference for private healthcare over public services P = <0.001). Odds ratio analysis corroborated these findings. Healthcare personnel emerged as the most common source of information for neurosurgical diseases (71.4%). CONCLUSIONS: Our findings suggest that sociodemographic factors such as age, education, and income correlate with the population's self-perceived knowledge, trust and beliefs about safety and effectiveness regarding neurosurgical care in Mexico. These findings can be instrumental for developing healthcare policies that address the needs of Mexico's patient population.

Assuntos

Procedimentos Neurocirúrgicos , Humanos , México , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Estudos Transversais , Adulto Jovem , Inquéritos e Questionários , Idoso , Conhecimentos, Atitudes e Prática em Saúde , Adolescente , Neurocirurgia , Fatores Socioeconômicos , Percepção

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Progesterone (P4) is a neuroactive hormone having pleiotropic effects, supporting its pharmacological potential to treat global (cardiac-arrest-related) cerebral ischemia, a condition associated with an elevated risk of dementia. This review examines the current biochemical, morphological, and functional evidence showing the neuroprotective/neurorestorative effects of P4 against global cerebral ischemia (GCI). Experimental findings show that P4 may counteract pathophysiological mechanisms and/or regulate endogenous mechanisms of plasticity induced by GCI. According to this, P4 treatment consistently improves the performance of cognitive functions, such as learning and memory, impaired by GCI. This functional recovery is related to the significant morphological preservation of brain structures vulnerable to ischemia when the hormone is administered before and/or after a moderate ischemic episode; and with long-term adaptive plastic restoration processes of altered brain morphology when treatment is given after an episode of severe ischemia. The insights presented here may be a guide for future basic research, including the study of P4 administration schemes that focus on promoting its post-ischemia neurorestorative effect. Furthermore, considering that functional recovery is a desired endpoint of pharmacological strategies in the clinic, they could support the study of P4 treatment for decreasing dementia in patients who have suffered an episode of GCI.

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The primary mechanism for neuron death after an ischemic stroke is excitotoxic injury. Excessive depolarization leads to NMDA-mediated calcium entry to the neuron and, subsequently, cellular death. Therefore, the inhibition of the NMDA channel has been proposed as a neuroprotective measure in ischemic stroke. The high morbimortality associated with stroke warrants new therapies that can improve the functional prognosis of patients. Memantine is a non-competitive NMDA receptor antagonist which has gained attention as a potential drug for ischemic stroke. Here we analyze the available preclinical and clinical evidence concerning the use of memantine following an ischemic stroke. Preclinical evidence shows inhibition of the excitotoxic cascade, as well as improved outcomes in terms of motor and sensory function with the use of memantine. The available clinical trials of high-dose memantine in patients poststroke have found that it can improve patients' NIHSS and Barthel index and help patients with poststroke aphasia and intracranial hemorrhage. These results suggest that memantine has a clinically relevant neuroprotective effect; however, small sample sizes and other study shortcomings limit the impact of these findings. Even so, current studies show promising results that should serve as a basis to promote future research to conclusively determine if memantine does improve the outcomes of patients' post-ischemic stroke. We anticipate that future trials will fill current gaps in knowledge, and these latter results will broaden the therapeutic arsenal for clinicians looking to improve the prognosis of patients poststroke.

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Purpose: Neurofibromatosis type 1 (NF1) is a complex, multisystem disorder that is characterized, among other features, by a higher risk of developing benign and malignant tumors. Despite NF1 being one of the most common autosomal dominant genetic disorders, data from adult individuals in several world regions remain elusive, including Hispanics. Methods: The present is a retrospective cohort study conducted among adult patients with a confirmed diagnosis of NF1 who attended a single cancer-reference center, the Instituto Nacional de Cancerología in Mexico City from 2001 to 2021. Data were extracted from electronic health records and collected in an anonymous database by an NF1-expert physician in order to obtain demographic characteristics and detailed information regarding the development of tumors among this patient subgroup. All patients with malignant tumors or with benign tumors, which severely affected their quality of life, were included in this study. Results: Patient records were reviewed from 2001 to 2021. A total of N = 29 patients met the criteria, with a higher proportion of female compared with male subjects [N = 22 (75.9%) vs. N = 7 (24.1%)]. Patients had a mean age at diagnosis of tumors of 32.2 years (SD = 11.2 years). In terms of malignant neoplasms, the most frequent malignant tumor presented by patients in this cohort was malignant peripheral nerve sheath tumors (N = 7, 24.1%), this was followed by breast cancer (n = 4, 13.8% among all patients, 18.2% among female patients). Other tumors also identified in this cohort included melanoma, gastrointestinal stromal tumors, and rectal cancer. Conclusion: In Mexico, patients diagnosed with NF1 develop diverse tumors as adults. As described in other studies, the most frequent malignant tumor in this patient population is the malignant peripheral nerve sheath tumor. Further studies are required to increase the scarce information available for adult Hispanics with NF1.

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The presence of insoluble aggregates of amyloid ß (Aß) in the form of neuritic plaques (NPs) is one of the main features that define Alzheimer's disease. Studies have suggested that the accumulation of these peptides in the brain significantly contributes to extensive neuronal loss. Furthermore, the content and distribution of cholesterol in the membrane have been shown to have an important effect on the production and subsequent accumulation of Aß peptides in the plasma membrane, contributing to dysfunction and neuronal death. The monomeric forms of these membrane-bound peptides undergo several conformational changes, ranging from oligomeric forms to beta-sheet structures, each presenting different levels of toxicity. Aß peptides can be internalized by particular receptors and trigger changes from Tau phosphorylation to alterations in cognitive function, through dysfunction of the cholinergic system. The goal of this review is to summarize the current knowledge on the role of lipids in Alzheimer's disease and their relationship with the basal cholinergic system, as well as potential disease-modifying therapies.

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Doença de Alzheimer , Peptídeos beta-Amiloides , Humanos , Peptídeos beta-Amiloides/metabolismo , Doença de Alzheimer/metabolismo , Metabolismo dos Lipídeos , Metabolismo Basal , Fragmentos de Peptídeos/metabolismo , Colinérgicos , Lipídeos

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Cancer is a complex group of diseases that constitute the second largest cause of mortality worldwide. The development of new drugs for treating this disease is a long and costly process, from the discovery of the molecule through testing in phase III clinical trials, a process during which most candidate molecules fail. The use of drugs currently employed for the management of other diseases (drug repurposing) represents an alternative for developing new medical treatments. Repurposing existing drugs is, in principle, cheaper and faster than developing new drugs. Antihypertensive drugs, primarily belonging to the pharmacological categories of angiotensin-converting enzyme inhibitors, angiotensin II receptors, direct aldosterone antagonists, ß-blockers and calcium channel blockers, are commonly prescribed and have well-known safety profiles. Additionally, some of these drugs have exhibited pharmacological properties useful for the treatment of cancer, rendering them candidates for drug repurposing. In this review, we examine the preclinical and clinical evidence for utilizing antihypertensive agents in the treatment of cancer.

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Alzheimer's disease (AD) is the most common form of dementia present in older adults; its etiology involves genetic and environmental factors. In recent years, epidemiological studies have shown a correlation between AD and chronic epilepsy since a considerable number of patients with AD may present seizures later on. Although the pathophysiology of seizures in AD is not completely understood, it could represent the result of several molecular mechanisms linked to amyloid beta-peptide (Aß) accumulation and the hyperphosphorylation of tau protein, which may induce an imbalance in the release and recapture of excitatory and inhibitory neurotransmitters, structural alterations of the neuronal cytoskeleton, synaptic loss, and neuroinflammation. These changes could favor the recurrent development of hypersynchronous discharges and epileptogenesis, which, in a chronic state, favor the neurodegenerative process and influence the cognitive decline observed in AD. Supporting this correlation, histopathological studies in the brain tissue of temporal lobe epilepsy (TLE) patients have revealed the presence of Aß deposits and the accumulation of tau protein in the neurofibrillary tangles (NFTs), accompanied by an increase of glycogen synthase kinase-3 beta (GSK3ß) activity that may lead to an imminent alteration in posttranslational modifications of some microtubule-associated proteins (MAPs), mainly tau. The present review is focused on understanding the pathological aspects of GSK3ß and tau in the development of TLE and AD.