Histological and Memory Alterations in an Innovative Alzheimer's Disease Animal Model by Vanadium Pentoxide Inhalation.

Background: Previous work from our group has shown that chronic exposure to Vanadium pentoxide (V2O5) causes cytoskeletal alterations suggesting that V2O5 can interact with cytoskeletal proteins through polymerization and tyrosine phosphatases inhibition, causing Alzheimer's disease (AD)-like hippocampal cell death. Objective: This work aims to characterize an innovative AD experimental model through chronic V2O5 inhalation, analyzing the spatial memory alterations and the presence of neurofibrillary tangles (NFTs), amyloid-ß (Aß) senile plaques, cerebral amyloid angiopathy, and dendritic spine loss in AD-related brain structures. Methods: 20 male Wistar rats were divided into control (deionized water) and experimental (0.02 M V2O5 1 h, 3/week for 6 months) groups (n = 10). The T-maze test was used to assess spatial memory once a month. After 6 months, histological alterations of the frontal and entorhinal cortices, CA1, subiculum, and amygdala were analyzed by performing Congo red, Bielschowsky, and Golgi impregnation. Results: Cognitive results in the T-maze showed memory impairment from the third month of V2O5 inhalation. We also noted NFTs, Aß plaque accumulation in the vascular endothelium and pyramidal neurons, dendritic spine, and neuronal loss in all the analyzed structures, CA1 being the most affected. Conclusions: This model characterizes neurodegenerative changes specific to AD. Our model is compatible with Braak AD stage IV, which represents a moment where it is feasible to propose therapies that have a positive impact on stopping neuronal damage.

Alzheimer-like cell death after vanadium pentoxide inhalation.

Vanadium (V) toxicity depends on its oxidation state; it seems that vanadium pentoxide (V2O5) is the most toxic to the living cells. It has been reported that oral administration induces changes in motor activity and learning; in rats, I.P. administration increases lipid peroxidation levels in the cerebellum and the concentration of free radicals in the hippocampus and cerebellum. Mice that inhaled V2O5 presented a reduced number of tubulin+ in Leydig and Sertoli cells; it has also been reported that inhaled V2O5 induces loss of dendritic spines, necrosis, and hippocampus neuropil alterations; considering the direct consequence of the interaction of V with cytoskeletal components, makes us believe that V2O5 exposure could cause neuronal death in the hippocampus similar to that seen in Alzheimer disease. This work aimed to determine pyramidal hippocampal CA1 cytoskeletal alterations with Bielschowsky stain in rats exposed to V2O5. Male Wistar rats inhaled 0.02 M of V2O5 one h two times a week for two and six months. We found that rats, which inhaled V2O5 reached 56,57% of dead neurons after six months of inhalation; we recognize strong argyrophilic and collapsed somas and typical flame-shaped in all V-exposed rats hippocampus CA1 compared to controls. We also observe somatodendritic distortions. Axons and dendrites displayed thick dark bands replaced by noticeable thickening and nodosities and the cytoskeleton fibrillary proteins' linear traces. Our findings suggest that V2O5 inhalation induces Alzheimer-like cell death with evident cytoskeletal alterations.

Intervención cognitivo-conductual en cuidados paliativos pediátricos: un caso clínico / Cognitive-behavioral intervention in pediatric palliative care: a clinical case

Objetivo: El cáncer infantil es una enfermedad que modifica el estilo y calidad de vida de los niños y sus familias debido al impacto físico, emocional y económico que provoca. Los Cuidados Paliativos Pediátricos tienen entre sus funciones otorgar atención psicológica a los niños y sus familiares desde la etapa prediagnóstica con la finalidad de mejorar el estado anímico del paciente y promover pensamientos y conductas que le permitan adaptarse a su nueva condición y mejoren la adherencia al tratamiento. Se expone el caso de una paciente pediátrica con diagnóstico de Sarcoma Sinovial que presenta sintomatología depresiva y evitación ansiosa a raíz de su padecimiento. Método: La evaluación se realizó mediante entrevista conductual y observación directa de la sintomatología ansiosa y depresiva intrahospitalaria y la Escala Visual Análoga (EVA) para el dolor. El tratamiento se llevó a cabo en siete sesiones en las que se emplearon técnicas de la Terapia Cognitivo-Conductual. Resultados: Entre los resultados se obtuvieron verbalizaciones adaptativas sobre su padecimiento, posibles tratamientos médicos, autoconcepto, una mejora en la expresión emocional y control del dolor. Conclusiones: El presente caso es una muestra de la importancia que tiene la labor del psicólogo en los Cuidados Paliativos Pediátricos, así comoel impacto del trabajo con los niños que padecen enfermedades oncológicas y sus familiares. La Terapia Cognitivo-Conductual ha demostrado ser altamente eficaz en este tipo de pacientes, aún en intervenciones breves

Objective: Childhood cancer is a disease that modifies the style and quality of life of children and their families due to the physical, emotional and financial impact it has on them. Pediatric Palliative Care has among its functions the granting of psychological attention to children and their families from the pre-diagnostic stage until terminal stage. We present the case of a pediatric patient diagnosed with Synovial Sarcoma who presents depression and anxious avoidance as a result of her medical condition. Method: The evaluation was carried out through a behavioral interview, direct observation of anxiety and depression responses in the hospital and Visual Analogue Scale (VAS) for pain. The treatment consisted of seven sessions of intervention with Cognitive-Behavioral Therapy techniques. Results: The obtained results include adaptive verbalizations about their condition, possible medical treatments, self-concept, an improvement in emotional expression and management of pain. Conclusion: This case is a sample of the importance of the work of the psychologist in Pediatric Palliative Care, as well as the impact of working with children suffering from oncological diseases and their families. Cognitive-Behavioral Therapy has been shown to be highly effective in this type of patients, even in brief interventions

The presence of perforated synapses in the striatum after dopamine depletion, is this a sign of maladaptive brain plasticity?

Synaptic plasticity is the process by which long-lasting changes take place at synaptic connections. The phenomenon itself is complex and can involve many levels of organization. Some authors separate forms into adaptations that have positive or negative consequences for the individual. It has been hypothesized that an increase in the number of synapses may represent a structural basis for the enduring expression of synaptic plasticity during some events that involve memory and learning; also, it has been suggested that perforated synapses increase in number after some diseases and experimental situations. The aim of this study was to analyze whether dopamine depletion induces changes in the synaptology of the corpus striatum of rats after the unilateral injection of 6-OHDA. The findings suggest that after the lesion, both contralateral and ipsilateral striata exhibit an increased length of the synaptic ending in ipsilateral (since third day) and contralateral striatum (since Day 20), loss of axospinous synapses in ipsilateral striatum and a significant increment in the number of perforated synapses, suggesting brain plasticity that might be deleterious for the spines, because this type of synaptic contacts are presumably excitatory, and in the absence of the modulatory effects of dopamine, the neuron could die through excitotoxic mechanisms. Thus, we can conclude that the presence of perforated synapses after striatal dopamine depletion might be a form of maladaptive synaptic plasticity.

The combination of oral L-DOPA/rimonabant for effective dyskinesia treatment and cytological preservation in a rat model of Parkinson's disease and L-DOPA-induced dyskinesia.

Parkinson's disease is the second most prevalent neurodegenerative disease in the world. Its treatment is limited so far to the management of parkinsonian symptoms with L-DOPA (LD). The long-term use of LD is limited by the development of L-DOPA-induced dyskinesias and dystonia. However, recent studies have suggested that pharmacological targeting of the endocannabinoid system may potentially provide a valuable therapeutic tool to suppress these motor alterations. In the present study, we have explored the behavioral (L-DOPA-induced dyskinesias severity) and cytological (substantia nigra compacta neurons and striatum neuropil preservation) effects of the oral coadministration of LD and rimonabant, a selective antagonist of CB1 receptors, in the 6-hydroxydopamine rat model of Parkinson's disease. Oral coadministration of LD (30 mg/kg) and rimonabant (1 mg/kg) significantly decreased abnormal involuntary movements and dystonia, possibly through the conservation of some functional tyrosine hydroxylase-immunoreactive dopaminergic cells, which in turn translates into a well-preserved neuropil of a less denervated striatum. Our results provide anatomical evidence that long-term coadministration of LD with cannabinoid antagonist-based therapy may not only alleviate specific motor symptoms but also delay/arrest the degeneration of striatal and substantia nigra compacta cells.

Evaluación del patrón de conducta tipo a en niños: un estudio longitudinal / Assessment of Type A behaviour pattern in children: a longitudinal study

El patrón de conducta Tipo A es el comportamiento observable que emerge cuando una persona predispuesta se enfrenta a una situación de reto. Los sujetos Tipo A son hostiles, agresivos, competitivos, muestran urgencia de tiempo e impaciencia. Quienes posean este patrón conductual se encuentran en riesgo de padecer enfermedades coronarias. Actualmente, la American Heart Association considera a este patrón como un factor de riesgo de igual magnitud que la hipercolesterolemia o la hipertensión. Dicho patrón puede ser detectado desde la infancia. Se trabajó con 39 niños de primaria, y se aplicó en cinco ocasiones un cuestionario que evalúa la conducta Tipo A. Los resultados mostraron aumentos de las puntuaciones en los sujetos al ir creciendo. Este tipo de estudios representan el inicio de investigaciones longitudinales con niños mexicanos, que en el futuro permitirán establecer la posible patogenia de la enfermedad coronaria y, por ende, sus formas de prevención (AU)