Glutathione Peroxidase gpx1 to gpx8 Genes Expression in Experimental Brain Tumors Reveals Gender-Dependent Patterns.

Extensive research efforts in the field of brain tumor studies have led to the reclassification of tumors by the World Health Organization (WHO) and the identification of various molecular subtypes, aimed at enhancing diagnosis and treatment strategies. However, the quest for biomarkers that can provide a deeper understanding of tumor development mechanisms, particularly in the case of gliomas, remains imperative due to their persistently incurable nature. Oxidative stress has been widely recognized as a key mechanism contributing to the formation and progression of malignant tumors, with imbalances in antioxidant defense systems being one of the underlying causes for the excess production of reactive oxygen species (ROS) implicated in tumor initiation. In this study, we investigated the gene expression patterns of the eight known isoforms of glutathione peroxidase (GPx) in brain tissue obtained from male and female control rats, as well as rats with transplacental ethyl nitrosourea (ENU)-induced brain tumors. Employing the delta-delta Ct method for RT-PCR, we observed minimal expression levels of gpx2, gpx5, gpx6, and gpx7 in the brain tissue from the healthy control animals, while gpx3 and gpx8 exhibited moderate expression levels. Notably, gpx1 and gpx4 displayed the highest expression levels. Gender differences were not observed in the expression profiles of these isoforms in the control animals. Conversely, the tumor tissue exhibited elevated relative expression levels in all isoforms, except for gpx4, which remained unchanged, and gpx5, which exhibited alterations solely in female animals. Moreover, except for gpx1, which displayed no gender differences, the relative expression values of gpx2, gpx3, gpx6, gpx7, and gpx8 were significantly higher in the male animals compared to their female counterparts. Hence, the analysis of glutathione peroxidase isoforms may serve as a valuable approach for discerning the behavior of brain tumors in clinical settings.

Low- and Negative-Pressure Hydrocephalus: New Report of Six Cases and Literature Review.

Low- or very-low-pressure hydrocephalus is a serious and rare phenomenon, which is becoming better known since it was first described in 1994 by Pang and Altschuler. Forced drainage at negative pressures can, in most cases, restore the ventricles to their original size, thus achieving neurological recovery. We present six new cases that suffered this syndrome from 2015 to 2020: two of them after medulloblastoma surgery; a third one as a consequence of a severe head trauma that required bifrontal craniectomy; another one after craniopharyngioma surgery; a fifth one with leptomeningeal glioneuronal tumor; and, finally, a patient with a shunt for normotensive hydrocephalus. Before the development of this condition, four of them had mid-low-pressure cerebrospinal fluid (CSF) shunts. Four patients required cerebrospinal fluid (CSF) drainage at negative pressures oscillating from zero to -15 mmHg by external ventricular drainage until ventricular size normalized, followed by the placement of a new definitive low-pressure shunt, one of them to the right atrium. The duration of drainage in negative pressures through external ventricular drainage (EVD) ranged from 10 to 40 days with concomitant intracranial pressure monitoring at the neurointensive care unit. Approximately 200 cases of this syndrome have been described in the literature. The causes are varied and superimposable to those of high-pressure hydrocephalus. Neurological impairment is due to ventricular size and not to pressure values. Subzero drainage is still the most commonly used method, but other treatments have been described, such as neck wrapping, ventriculostomy of the third ventricle, and lumbar blood patches when associated with lumbar puncture. Its pathophysiology is not clear, although it seems to involve changes in the permeability and viscoelasticity of the brain parenchyma together with an imbalance in CSF circulation in the craniospinal subarachnoid space.

Tumor glioneuronal leptomeníngeo difuso: diagnóstico y tratamiento con un caso ilustrativo / Diffuse leptomeningeal glioneuronal tumor: A review of diagnosis and management with an illustrative case

El tumor glioneuronal leptomeníngeo difuso es una entidad infrecuente, con un curso indolente; fue descrito en la clasificación de los tumores del sistema del sistema nervioso central de la OMS 2016. Presentamos el caso de un varón de 11 años que comienza con un cuadro clínico inespecífico de cefalea, dolor lumbosacro e hidrocefalia comunicante. En el curso clínico aparecen crisis epilépticas con lesiones nodulares en RM craneal; fue diagnosticado de meningitis tuberculosa y tratado con tuberclostáticos. Ante un deterioro clínico progresivo, a pesar del tratamiento, y empeoramiento de los hallazgos en RM craneoespinal, se le realiza biopsia cerebral y de leptomeninges que confirma el diagnóstico de tumor glioneuronal leptomeníngeo difuso. El tumor glioneuronal leptomeníngeo difuso debe incluirse en el diagnóstico diferencial de los cuadros que se presentan con hidrocefalia comunicante y lesiones leptomeníngeas. Se precisa un diagnóstico histológico precoz mediante biopsia para establecer un tratamiento adecuado (AU)

Diffuse leptomeningeal glioneuronal tumors (DLGNTs) are a rare indolent neoplasm described in the 2016 WHO classification of tumors of the central nervous system (CNS). We describe a case of an 11 year old boy who initially presented intermittent headache, low back pain and communicating hydrocephalus, misdiagnosed as having tuberculous meningitis. Further clinical deterioration with seizures was observed and follow-up MRI showed further aggravation of leptomeningeal enhancement in the basal cisterns. Biopsy of the brain and leptomeninges revealed a diffuse leptomeningeal glioneuronal tumor. DLGNT should be considered in the differential diagnosis of conditions presenting as communicating hydrocephalus with nodular lesions and leptomeningeal enhancement. A timely histologic diagnosis through a biopsy of the brain is necessary to confirm the diagnosis (AU)

Diffuse leptomeningeal glioneuronal tumor: A review of diagnosis and management with an illustrative case.

Diffuse leptomeningeal glioneuronal tumors (DLGNTs) are a rare indolent neoplasm described in the 2016 WHO classification of tumors of the central nervous system (CNS). We describe a case of an 11 year old boy who initially presented intermittent headache, low back pain and communicating hydrocephalus, misdiagnosed as having tuberculous meningitis. Further clinical deterioration with seizures was observed and follow-up MRI showed further aggravation of leptomeningeal enhancement in the basal cisterns. Biopsy of the brain and leptomeninges revealed a diffuse leptomeningeal glioneuronal tumor. DLGNT should be considered in the differential diagnosis of conditions presenting as communicating hydrocephalus with nodular lesions and leptomeningeal enhancement. A timely histologic diagnosis through a biopsy of the brain is necessary to confirm the diagnosis.