Longitudinal magnetic resonance evaluation of the schizophrenia model of neonatal lesion in the ventral hippocampus.

OBJECTIVE: To evaluate the progression by means of nuclear magnetic resonance of the lesion in the schizophrenia model of lesion of the ventral hippocampal nucleus (LVNH). METHOD: Magnetic resonance imaging (MRI) were performed in male Wistar rats, from 8 days postnatal to 139 days, in animals with LNHV and without lesion (sham). The MRI were carried out on a Variant 7 T equipment. The data were analyzed with the Amira software, for a voxel-based morphometric analysis. RESULTS: We observed the presence of hypersignals with a significant enhancement in the structures analyzed in the group with LVNH, and greater volume in the lateral ventricles, presenting a larger size of the lesion on day PD96 and significantly reducing on day PD139. CONCLUSIONS: We found a cell rearrangement during the progression of the lesion, which could be the effect of the activation of immune cells.

OBJETIVO: Evaluar mediante resonancia magnética (RM) la progresión de la lesión en el modelo de esquizofrenia de lesión del núcleo del hipocampo ventral (LNHV). MÉTODO: Se realizaron RM en ratas Wistar macho, desde los 8 días posnatales hasta los 139 días, en animales con LNHV y sin lesión (sham). Las RM se realizaron con un equipo Variant de 7 T. Los datos se analizaron con el software Amira para un análisis de morfometría basada en vóxels. RESULTADOS: Observamos hiperseñales con un realce significativo en las estructuras analizadas en el grupo con LNHV, y mayor volumen en los ventrículos laterales, presentando un mayor tamaño de la lesión el día PD96 y significativamente reducido en el día PD139. CONCLUSIONES: Encontramos un reacomodo celular durante la progresión de la lesión, lo cual podría ser efecto de la activación de las células inmunitarias.

Astrocyte-Derived Small Extracellular Vesicles Regulate Dendritic Complexity through miR-26a-5p Activity.

In the last few decades, it has been established that astrocytes play key roles in the regulation of neuronal morphology. However, the contribution of astrocyte-derived small extracellular vesicles (sEVs) to morphological differentiation of neurons has only recently been addressed. Here, we showed that cultured astrocytes expressing a GFP-tagged version of the stress-regulated astrocytic enzyme Aldolase C (Aldo C-GFP) release small extracellular vesicles (sEVs) that are transferred into cultured hippocampal neurons. Surprisingly, Aldo C-GFP-containing sEVs (Aldo C-GFP sEVs) displayed an exacerbated capacity to reduce the dendritic complexity in developing hippocampal neurons compared to sEVs derived from control (i.e., GFP-expressing) astrocytes. Using bioinformatics and biochemical tools, we found that the total content of overexpressed Aldo C-GFP correlates with an increased content of endogenous miRNA-26a-5p in both total astrocyte homogenates and sEVs. Notably, neurons magnetofected with a nucleotide sequence that mimics endogenous miRNA-26a-5p (mimic 26a-5p) not only decreased the levels of neuronal proteins associated to morphogenesis regulation, but also reproduced morphological changes induced by Aldo-C-GFP sEVs. Furthermore, neurons magnetofected with a sequence targeting miRNA-26a-5p (antago 26a-5p) were largely resistant to Aldo C-GFP sEVs. Our results support a novel and complex level of astrocyte-to-neuron communication mediated by astrocyte-derived sEVs and the activity of their miRNA content.

[Behavioral assessment of the "schizophrenia-like" phenotype in an animal model of neonatal lesion in the ventral hippocampus (NLVH) of young and adult rats]. / Evaluación conductual del fenotipo «esquizofrenia¼ en un modelo animal por lesión neonatal del hipocampo ventral en ratas juveniles y adultas.

Schizophrenia is a serious mental disorder that affects one in 100 people worldwide, and is characterized by distorted thoughts and perceptions. Several animal models have been developed, based primarily on the study of the mechanism of action of antipsychotics. In this paper we present a number of classic behavioral tests (memory, social interaction, and pre-pulse inhibition) associated with schizophrenia in young and adult animals with NLVH. The animal model of NLVH is a heuristic model that discriminates, by behavioral testing, the phenotype "schizophrenia-like" from other behavioral paradigms such as depression and anxiety, specifically in adult animals. The genomics study of this model promises to be an important source of candidate genes for schizophrenia in humans.

Are major repeater patients addicted to suicidal behavior?

The literature provides support for the hypothesis that some major repeaters (individuals with >=5 lifetime suicide attempts) are addicted to suicidal behavior (SB). This study explores whether major repeaters are addicted to SB or not using 7 criteria: tolerance (Criterion 1), withdrawal (Criterion 2), loss of control (Criterion 3), problems in quitting/cutting down (Criterion 4), much time spent using (Criterion 5), substantial reduction in activities (Criterion 6), and adverse physiological/physical consequences (Criterion 7). Total dependence on SB was indicated by the presence of 3 or more of the 7 criteria in the last 12 months. This cross-sectional study at Puerta de Hierro University Hospital (Madrid, Spain) recruited 118 suicide attempters including 8 major repeaters (7%, 8/118), who were all females. The association between each SB addiction criterion, physiological dependence and total dependence with major repeater status was tested for significance and for effect size with odds ratios (ORs) and their 95% confidence intervals. As hypothesized, major repeaters met significantly higher frequency of criteria for total dependence on SB, OR=62.9 (6.4-615). A backward stepwise logistic regression model was used to provide an OR between major repeater status and total dependence status corrected by confounding variables. Age, panic disorder without agoraphobia, borderline personality disorder, history of psychiatric inpatient admission, and total dependence on SB were introduced as independent variables with major repeater status as the dependent variable. The model selected total dependence and age as the remaining significant variables in the last step. Accordingly, major repeaters appear to be addicted to SB.

Vaporización láser CO2 de amígdalas en niños: una técnica segura y eficaz / CO2 laser vaporization of tonsils in children: a safe and effective technique

Introducción: La hipertrofia amigdalina es una de las principales causas de ronquido infantil, tiene una prevalencia que oscila entre el 9 y el 10% y alcanza hasta el 30% en niños de 3-6 años. Se debe nombrar que solo el 3% de ese 30% tienen OSA, pues esa es la verdadera indicación de la cirugía. El objetivo fue evaluar la seguridad y eficacia de la vaporización de amígdalas con láser CO2 en pacientes pediátricos con OSA, del Servicio de Otorrinolaringología de la Clínica Carlos Ardila Lülle - Bucaramanga. Métodos: Estudio descriptivo de 47 niños entre 3 y 11 años, sometidos al procedimiento entre enero del 2011 y febrero del 2012, por obstrucción ventilatoria alta con pausas respiratorias mayores de 10 segundos durante el sueño, secundaria a hipertrofia del tejido amigdalino. Resultados: 97,8% de los niños estudiados tenían amígdalas grado IV y 2,1% grado III. Se debe exponer por qué existe tan alto porcentaje en el grado IV, pues la diferencia es muy grande, y eso puede ser objeto de censura. El tiempo quirúrgico fue, en promedio, de 25 minutos. En el 100% el procedimiento fue ambulatorio. Hay que tener cuidado con esto, porque los niños que van a cirugía por OSA como indicación deben someterse a hospitalización posterior en la UCI, pues corren el riesgo de presentar apneas, puesto que sus receptores de CO2 disminuyen la sensibilidad de hipoxia, pues al quitar el tejido no hay obstrucción; entonces, sus niveles de CO2 se reducen mucho, y esto es lo único que estimula en los centros respiratorios de ellos, y así se produce la apnea. 24 niños no registraron dolor (51%), y dos presentaron emesis (0,94%). La evolución postintervención fue satisfactoria en la mayoría, y ninguno de los pacientes presentó cuadros de sangrado o infección. Un mes después del procedimiento, 98% de los padres referían una notable mejoría de la respiración oral (ronquido), del sueño y los síntomas diurnos, o episodios de apnea. De lo contrario, sería una cirugía sin criterios adecuados, según lo relatado en la literatura. En ninguno de los pacientes que cumplieron un año de evolución se evidenció hipertrofia del tejido residual...

Introduction: Tonsillar hypertrophy is one of main causes of child snoring, having a prevalence ranging between 9 and 10% and reaching until 30% in children between 3 to 6 years old. The aim of our study was to determinate the efficacy and safety of tonsil laser vaporization with CO2 in the Otorrinolaryngology Service at the Clínica Carlos Ardila Lülle, Bucaramanga, Colombia. Methods: Descriptive study on 47 children between 3 and 11 years old, who underwent tonsil laser vaporization with CO2 in the last year by presented high ventilatory obstruction secondary to tonsillar hypertrophy tissue. Results: 97.8% had Grade IV tonsils and 2.1% were grade III. The operating time averaged 25 minutes. The 100% of the procedures were ambulatory. 24 children no reported pain (51%), 2 patients experienced emesis (0.94%). The evolution was satisfactory in more of them and not body presented bleeding or infection. After one month, 98% of parents reported a significant improvement in mouth breathing, snoring, sleep, and daily symptoms. Between children with one year evolution nobody of them presented residual tissue hypertrophy...