Astrocytes As the Main Players in Primary Degenerative Disorders of the Human Central Nervous System.

Along the last years it has been demonstrated that non-neural cells play a major role in the pathogenesis of the primary degenerative disorders (PDDs) of the human central nervous system. Among them, astrocytes coordinate and participate in many different and complex metabolic processes, in close interaction with neurons. Moreover, increasing experimental evidence hints an early astrocytic dysfunction in these diseases. In this mini review we summarize the astrocytic behavior in PDDs, with special consideration to the experimental observations where astrocytic pathology precedes the development of neuronal dysfunction. We also suggest a different approach that could be consider in human investigations in Alzheimer's and Parkinson's disease. We believe that the study of PDDs with human brain samples may hold the key of a paradigmatic physiopathological process in which astrocytes might be the main players.

Morphological abnormalities in mitochondria of the skin of patients with sporadic amyotrophic lateral sclerosis.

OBJECTIVES: Mitochondrial dysfunction has been reported in the central nervous system, hepatocytes and peripheral blood lymphocytes from patients with sporadic amyotrophic lateral sclerosis (SALS). However, the status of skin mitochondria has not been reported, in spite of the fact that SALS patients present skin abnormalities. The objective of the present study was to compare mitochondrial ultrastructural parameters in keratinocytes from patients with SALS and healthy controls. METHODS: Our study was based on the analysis of 112 skin mitochondria from 5 SALS patients and 99 organelles from 4 control subjects by electron microscopy. RESULTS: Computerized image analysis showed that mitochondrial major axis length, area and perimeter of the organelle were significantly smaller in SALS respect of healthy control subjects. Morphologically, SALS mitochondria presented cristolysis and breakage of the outer membrane. CONCLUSIONS: Mitochondrial dysfunction in the skin may possibly reflect changes occurring in mitochondria of the central nervous system. The analysis of mitochondrial morphology in this tissue may be of value to follow disease progression and, eventually, the effectiveness of current therapies for SALS.

Morphological abnormalities in mitochondria of the skin of patients with sporadic amyotrophic lateral sclerosis / Alteraciones morfológicas en las mitocondrias en la piel de enfermos con esclerosis lateral amiotrófica esporádica

OBJECTIVES: Mitochondrial dysfunction has been reported in the central nervous system, hepatocytes and peripheral blood lymphocytes from patients with sporadic amyotrophic lateral sclerosis (SALS). However, the status of skin mitochondria has not been reported, in spite of the fact that SALS patients present skin abnormalities. The objective of the present study was to compare mitochondrial ultrastructural parameters in keratinocytes from patients with SALS and healthy controls. METHODS: Our study was based on the analysis of 112 skin mitochondria from 5 SALS patients and 99 organelles from 4 control subjects by electron microscopy. RESULTS: Computerized image analysis showed that mitochondrial major axis length, area and perimeter of the organelle were significantly smaller in SALS respect of healthy control subjects. Morphologically, SALS mitochondria presented cristolysis and breakage of the outer membrane. CONCLUSIONS: Mitochondrial dysfunction in the skin may possibly reflect changes occurring in mitochondria of the central nervous system. The analysis of mitochondrial morphology in this tissue may be of value to follow disease progression and, eventually, the effectiveness of current therapies for SALS.

OBJETIVOS: Existen alteraciones en la función mitocondrial en el sistema nervioso central, en hepatocitos y en linfocitos de sangre periférica en SALS. Aunque, no se ha estudiado si existen cambios estructurales en las mitocondrias de la piel. Nuestro objetivo fue comparar la ultraestructura de mitocondrias en queratinocitos de enfermos con SALS con la de controles sanos. MÉTODO: Fueron analizadas en el microscopio electrónico 112 mitocondrias dérmicas de 5 pacientes y 99 provenientes de 4 controles. RESULTADOS: EL análisis computarizado mostró que el eje mayor mitocondrial, el área y el perímetro de las organelas fueran significativamente menor que en controles. Morfológicamente, las mitocondrias de SALS presentaron cristólisis y ruptura de la membrana externa. CONCLUSIÓN: La alteración mitocondrial en la piel posiblemente refleje cambios que también ocurran en las mitocondrias neuronales. Este análisis morfológico de las mitocondrias podría tener valor en el seguimiento de la enfermedad y eventualmente en la evaluación de la efectividad de futuras terapias.

Epidemiology of amyotrophic lateral sclerosis patients in a centre in Buenos Aires / Epidemiología de los pacientes con esclerosis lateral amiotrófica en el centro de Buenos Aires

Sporadic amyotrophic lateral sclerosis (sALS) is considered a multifactorial disease with genetic and environmental factors causing motor neuron degeneration. OBJECTIVE: To describe the epidemiological and occupational characteristics of patients with sALS who attended the Ramos Mejía Hospital at Buenos Aires, Argentina. METHOD: We analyzed the medical records of sALS patients diagnosed between 2001 and 2008. All occupations were coded according to the International Standard Classification of Occupation (ISCO). RESULTS: 187 patients were assessed, 38.5 percent were women and 61.5 percent men. Mean age at diagnosis was 55 years. 16 percent of them came from rural areas; 68 percent of the studied population had no health insurance. 40 percent were employed in elementary occupations, 19 were technicians and 8 handicraftsmen. CONCLUSION: The most represented profession was elementary occupation. A large proportion of patients came from rural areas, which might suggest an increased risk of environmental exposure to an unknown agent in those regions.

La esclerosis lateral amiotrófica esporádica (ELAe) es considerada una enfermedad multifactorial. OBJETIVO: Describir las características epidemiológicas y laborales de un grupo de pacientes con ELAe que fueron evaluados en el Hospital Ramos Mejía de Buenos Aires, Argentina. MÉTODO: Se analizaron los registros médicos de pacientes con ELAe diagnosticados entre 2001 y 2008. Las ocupaciones fueron codificadas de acuerdo a la Clasificación Internacional de Ocupaciones (ISCO). RESULTADOS: 187 pacientes fueron evaluados, 38,5 por ciento mujeres y 61,5 por ciento hombres. Edad media al diagnóstico 55 años. 16 por ciento procedían de zonas rurales, 68 por ciento no tenía seguro de salud. 40 por ciento se encontraba empleado en ocupaciones elementales, 19 por ciento eran técnicos , 8 por ciento artesanos y 7 por ciento operadores de maquinas. CONCLUSIÓN: La profesión más representada fue la de ocupación elemental. Una gran proporción de los pacientes provenían de zonas rurales, lo que podría sugerir un mayor riesgo de exposición ambiental a un agente desconocido en esas regiones.

Sporadic amyotrophic lateral sclerosis: new hypothesis regarding its etiology and pathogenesis suggests that astrocytes might be the primary target hosting a still unknown external agent.

This article briefly describes the already known clinical features and pathogenic mechanisms underlying sporadic amyotrophic lateral sclerosis, namely excitoxicity, oxidative stress, protein damage, inflammation, genetic abnormalities and neuronal death. Thereafter, it puts forward the hypothesis that astrocytes may be the cells which serve as targets for the harmful action of a still unknown environmental agent, while neuronal death may be a secondary event following the initial insult to glial cells. The article also suggests that an emergent virus or a misfolded infectious protein might be potential candidates to accomplish this task.

Sporadic amyotrophic lateral sclerosis: new hypothesis regarding its etiology and pathogenesis suggests that astrocytes might be the primary target hosting a still unknown external agent / Esclerosis lateral amiotrófica esporádica: nueva hipótesis relacionada con su etiología y patogenia que sugiere que los astrocitos podrían ser el blanco primario alojando un agente nocivo aun desconocido

This article briefly describes the already known clinical features and pathogenic mechanisms underlying sporadic amyotrophic lateral sclerosis, namely excitoxicity, oxidative stress, protein damage, inflammation, genetic abnormalities and neuronal death. Thereafter, it puts forward the hypothesis that astrocytes may be the cells which serve as targets for the harmful action of a still unknown environmental agent, while neuronal death may be a secondary event following the initial insult to glial cells. The article also suggests that an emergent virus or a misfolded infectious protein might be potential candidates to accomplish this task.

El artículo presente describe, brevemente, las características clínicas y los mecanismos patogénicos de la esclerosis lateral amiotrófica esporádica, tales como la excitotoxicidad, el stress oxidativo, el daño proteico, la inflamación, las anormalidades genéticas y la muerte neuronal. Luego de ello, sugiere la posibilidad hipotética de que los astrocitos podrían ser el blanco primario de la acción de una agente ambiental, externo, aún desconocido, y que la muerte neuronal aconteciera secundariamente a ese daño astrocitario inicial. El artículo concluye discutiendo la posibilidad de que un virus ambiental o endógeno o una proteína mal plegada, que adquiriera características de infectividad, puedan ser la causa de la enfermedad.

Epidemiology of amyotrophic lateral sclerosis patients in a centre in Buenos Aires.

UNLABELLED: Sporadic amyotrophic lateral sclerosis (sALS) is considered a multifactorial disease with genetic and environmental factors causing motor neuron degeneration. OBJECTIVE: To describe the epidemiological and occupational characteristics of patients with sALS who attended the Ramos Mejía Hospital at Buenos Aires, Argentina. METHOD: We analyzed the medical records of sALS patients diagnosed between 2001 and 2008. All occupations were coded according to the International Standard Classification of Occupation (ISCO). RESULTS: 187 patients were assessed, 38.5% were women and 61.5% men. Mean age at diagnosis was 55 years. 16% of them came from rural areas; 68% of the studied population had no health insurance. 40% were employed in elementary occupations, 19 were technicians and 8 handicraftsmen. CONCLUSION: The most represented profession was elementary occupation. A large proportion of patients came from rural areas, which might suggest an increased risk of environmental exposure to an unknown agent in those regions.

Prenatal cerebral magnetic resonance imaging.

UNLABELLED: Ultrasonography (USG) is the preferred screening method for fetal brain examination. It has some technical limitations and a relatively low sensibility and specificity for many central nervous system (CNS) malformations. Fetal cerebral magnetic resonance imaging (MRI) offers better resolution and sensibility, with scarce limitations. OBJECTIVES: To determine the fetal age according to cortical maturation as seen in MRI, correlating these data with those obtained by means of USG measurements; to correlate USG pathological findings with the MRIs and to determine how the sequence of cortical maturation varies in abnormal brains. MATERIALS AND METHODS: 50 pregnant women were submitted to USG and fetal brain MRI. Fifteen carried out normal pregnancies. In the remaining 35, the USG, the clinical assessment or both, raised the suspicion of a CNS malformation. Facts studied were: the gestational age calculated by USG, analysis of the cortical gyral development by MRI (cortical age), the presence of CNS abnormalities and the correlation between the cortical maturation and the presence of CNS pathologies. Statistical analysis included the Student's t test for paired samples, the Pearson's correlation coefficient (r) and linear regression curves. RESULTS: In the control group, fetal age highly correlated with the cortical age estimated by MRI. In the abnormal group, a wide variety of pathologies could be found, with higher sensibility and specificity than USG when applying MRI techniques. Cortical age did not correlate with the gestational age in this group; moreover, its estimation could not be achieved in severely malformed brains. DISCUSSION: MRI allows a detailed study of the CNS before birth. It proved to be more reliable and specific than USG, with fewer technical limitations. Cortical maturation can be accurately assessed by this method in normal or slightly abnormal fetuses. However, USG is better than MRI for diagnosing skull bony defects.

Outcome of sporadic amyotrophic lateral sclerosis treated with non-invasive ventilation and riluzole.

Sporadic amyotrophic lateral sclerosis (sALS) is a progressive degenerative motor neuron disorder lacking specific treatment. Riluzole is the only drug able to modestly slow down the course of the disease. Respiratory insufficiency is the main cause of death; non invasive ventilation (NIV) has shown to improve survival. Our aim was to evaluate the effect of NIV and riluzole on survival. Ninety seven patients with a diagnosis of sALS were assessed and followed up for 60 months. Twenty nine patients received NIV and 68 did not (nNIV). Overall median survival In the NIV group was 15.41 +/- 7.78 months vs. 10.88 +/- 7.78 months in the nNIV group (p= 0.028). Median survival time was not different in patients receiving riluzole (n=44), as compared with those who did not (n=53), although at month 4th and 5th riluzole treated patients showed a modest benefit. In those who only received NIV (n=11) or only riluzole (n=26), survival time was 13.45 +/- 13.44 months and 11.19 +/- 7.79 months, respectively. Patients who received both NIV and riluzole (n=18) had a median survival time of 16.61 +/- 10.97 months vs. 10.69 +/- 7.86 months for those who received only supportive treatment (n=42) (p= 0.021). NIV improved survival in our series of patients. Riluzole did not show any significant impact on survival when employed as the only therapy. Patients receiving both treatments simultaneously had a significant longer survival.

Outcome of sporadic amyotrophic lateral sclerosis treated with non-invasive ventilation and riluzole / Sobrevida en pacientes con esclerosis lateral amiotrófica esporádica tratados con ventilación no invasiva y riluzole

Sporadic amyotrophic lateral sclerosis (sALS) is a progressive degenerative motor neuron disorder lacking specific treatment. Riluzole is the only drug able to modestly slow down the course of the disease. Respiratory insufficiency is the main cause of death; non invasive ventilation (NIV) has shown to improve survival. Our aim was to evaluate the effect of NIV and riluzole on survival. Ninety seven patients with a diagnosis of sALS were assessed and followed up for 60 months. Twenty nine patients received NIV and 68 did not (nNIV). Overall median survival In the NIV group was 15.41 ± 7.78 months vs. 10.88 ± 7.78 months in the nNIV group (p= 0.028). Median survival time was not different in patients receiving riluzole (n=44), as compared with those who did not (n=53), although at month 4th and 5th riluzole treated patients showed a modest benefit. In those who only received NIV (n=11) or only riluzole (n=26), survival time was 13.45 ± 13.44 months and 11.19 ± 7.79 months, respectively. Patients who received both NIV and riluzole (n=18) had a median survival time of 16.61 ± 10.97 months vs. 10.69 ± 7.86 months for those who received only supportive treatment (n=42) (p= 0.021). NIV improved survival in our series of patients. Riluzole did not show any significant impact on survival when employed as the only therapy. Patients receiving both treatments simultaneously had a significant longer survival.

La esclerosis lateral amiotrófica esporádica (sALS) es una enfermedad degenerativa para la que no existe tratamiento etiológico eficaz. El riluzole prolonga poco la sobrevida. La principal causa de muerte es la insuficiencia respiratoria. Uno de los tratamientos para esta última es la ventilación asistida no invasiva (NIV) con equipos de doble nivel de presión. El objetivo de este trabajo fue determinar el impacto en la sobrevida de estos enfermos combinando ventilación no invasiva y riluzole. Se evaluaron y siguieron durante 60 meses 97 pacientes con diagnóstico de sALS, según criterios definidos en El Escorial modificados, y fueron seguidos por 60 meses. Veintinueve pacientes recibieron NIV y 68 no (nNIV). En el grupo NIV la sobrevida media fue de 15.41 ± 7.78 meses vs. 10.88 ± 7.78 meses en nNIV (p= 0.028). La sobrevida media de los pacientes que recibieron riluzole (n=44) no fue diferente de la que no lo recibieron (n=53), aunque en el 4° y 5° mes los pacientes tratados con riluzole mostraron un escaso beneficio. Los pacientes que recibieron NIV y riluzole (n=18) tuvieron una sobrevida media de 16.61 ± 10.97 meses vs. 10.69 ± 7.86 meses para los que sólo recibieron tratamiento sintomático (n=42) (p= 0.021). La NIV prolongó significativamente la sobrevida en este grupo de pacientes. El riluzole, empleado como única terapéutica, no lo hizo. Los pacientes que combinaron los dos tratamientos tuvieron la mayor sobrevida.

Outcome of sporadic amyotrophic lateral sclerosis treated with non-invasive ventilation and riluzole / Sobrevida en pacientes con esclerosis lateral amiotrófica esporádica tratados con ventilación no invasiva y riluzole

Sporadic amyotrophic lateral sclerosis (sALS) is a progressive degenerative motor neuron disorder lacking specific treatment. Riluzole is the only drug able to modestly slow down the course of the disease. Respiratory insufficiency is the main cause of death; non invasive ventilation (NIV) has shown to improve survival. Our aim was to evaluate the effect of NIV and riluzole on survival. Ninety seven patients with a diagnosis of sALS were assessed and followed up for 60 months. Twenty nine patients received NIV and 68 did not (nNIV). Overall median survival In the NIV group was 15.41 ± 7.78 months vs. 10.88 ± 7.78 months in the nNIV group (p= 0.028). Median survival time was not different in patients receiving riluzole (n=44), as compared with those who did not (n=53), although at month 4th and 5th riluzole treated patients showed a modest benefit. In those who only received NIV (n=11) or only riluzole (n=26), survival time was 13.45 ± 13.44 months and 11.19 ± 7.79 months, respectively. Patients who received both NIV and riluzole (n=18) had a median survival time of 16.61 ± 10.97 months vs. 10.69 ± 7.86 months for those who received only supportive treatment (n=42) (p= 0.021). NIV improved survival in our series of patients. Riluzole did not show any significant impact on survival when employed as the only therapy. Patients receiving both treatments simultaneously had a significant longer survival.(AU)

La esclerosis lateral amiotrófica esporádica (sALS) es una enfermedad degenerativa para la que no existe tratamiento etiológico eficaz. El riluzole prolonga poco la sobrevida. La principal causa de muerte es la insuficiencia respiratoria. Uno de los tratamientos para esta última es la ventilación asistida no invasiva (NIV) con equipos de doble nivel de presión. El objetivo de este trabajo fue determinar el impacto en la sobrevida de estos enfermos combinando ventilación no invasiva y riluzole. Se evaluaron y siguieron durante 60 meses 97 pacientes con diagnóstico de sALS, según criterios definidos en El Escorial modificados, y fueron seguidos por 60 meses. Veintinueve pacientes recibieron NIV y 68 no (nNIV). En el grupo NIV la sobrevida media fue de 15.41 ± 7.78 meses vs. 10.88 ± 7.78 meses en nNIV (p= 0.028). La sobrevida media de los pacientes que recibieron riluzole (n=44) no fue diferente de la que no lo recibieron (n=53), aunque en el 4º y 5º mes los pacientes tratados con riluzole mostraron un escaso beneficio. Los pacientes que recibieron NIV y riluzole (n=18) tuvieron una sobrevida media de 16.61 ± 10.97 meses vs. 10.69 ± 7.86 meses para los que sólo recibieron tratamiento sintomático (n=42) (p= 0.021). La NIV prolongó significativamente la sobrevida en este grupo de pacientes. El riluzole, empleado como única terapéutica, no lo hizo. Los pacientes que combinaron los dos tratamientos tuvieron la mayor sobrevida.(AU)

[Social cognition and theory of mind assessment in non-demented patients with isolated cerebellar degeneration]. / Evaluación de la cognición social y teoría de la mente en pacientes con enfermedad cerebelosa degenerativa aislada no dementes.

AIM: To investigate whether the cerebellum could participate in social cognition (SC). METHOD: General neuropsychological tests, executive tests (EF), social cognition tests, which assess the ability to infer other peoples mental states, and the Beck Depression Inventory were given to 10 non-demented patients with isolated cerebellar degenerative disease, and to 10 healthy controls matched for sex, age, and years of education. ANOVA and correlation coefficients were employed for the statistical analysis. RESULTS: Patients within the cerebellar group were significantly impaired (p

Evaluación de la cognición social y teoría de la mente en pacientes con enfermedad cerebelosa degenerativa aislada no dementes / Social cognition and theory of mind assessment in non-demented patients with isolated cerebellar degeneration

OBJETIVO: Investigar la hipótesis según la cual, el cerebelo podría participar en las alteraciones de la cognición social (CS). MÉTODO: Se administraron tests neuropsicológicos generales, de función ejecutiva (FE), de CS que evaluaban la capacidad de inferir el estado mental de otras personas y la escala de Depresión de Beck a 10 pacientes adultos con enfermedad cerebelosa adquirida aislada (GEC) y a 10 controles (GCO) apareados por edad, sexo y educación. Se analizaron los datos mediante ANOVA y correlación. RESULTADOS: El GEC obtuvo puntajes significativamente menores (p?0,05) que el grupo GCO en tareas de FE (Test de Wisconsin) y preguntas de creencia (PCr) de Teoría de la Mente (ToM). El rendimiento en las preguntas de control (PCo) de ToM fue similar en ambos grupos. El menor rendimiento en las PCr correlacionó significativamente con una menor habilidad conceptual, la severidad de la apatía (NPI) y de la ataxia estática. Las PCo correlacionaron con medidas de atención y de recuerdo diferido libre. CONCLUSíON: El cerebelo contribuiría en el monitoreo de la conducta mediante el control de datos multimodales motores, cognitivos y emocionales.

AIM: To investigate whether the cerebellum could participate in social cognition (SC). METHOD: General neuropsychological tests, executive tests (EF), social cognition tests, which assess the ability to infer other peoples mental states, and the Beck Depression Inventory were given to 10 non-demented patients with isolated cerebellar degenerative disease, and to 10 healthy controls matched for sex, age, and years of education. ANOVA and correlation coefficients were employed for the statistical analysis. RESULTS: Patients within the cerebellar group were significantly impaired (p?0.05) in EF test [Wisconsin Card Sorting Test (WSCT)] and belief questions (BQ) from Theory of Mind (ToM) tests. Performance in control questions (CQ) from ToM tests was similar for both groups. Lower scores in BQ correlated with a lower conceptual ability, the severity of apathy (NPI) and static ataxia. CQ correlated with measures of attention and free recall. CONCLUSION: The cerebellum may contribute in the control of social behavior through the processing of multimodal data, motor, cognitive and emotional.

[Comparison study of executive functions in Parkinson's disease and degenerative cerebellar disease's patients]. / Estudio comparativo de las funciones ejecutivas entre pacientes con enfermedad de Parkinson y pacientes con enfermedad degenerativa cerebelosa.

OBJECTIVE: To compare executive functions (EF) in non-demented mild to moderate Parkinson's disease (PD) (Hoehn and Yahr < or =3) and pure degenerative cerebellar disease (CD) in order to evaluate the relative contribution and differential role of basal ganglia and cerebellum in those functions. METHOD: 14 patients with PD and 14 patients with CD matched by sex, education, disease's duration and MMSE were selected. A standardized neuropsychological battery and the Wisconsin Card Sorting Test (WCST) were administered. Z scores were compared for both groups through t-test for independent samples were used. RESULTS: The cerebellar group showed significant lower performance in measures of attention and EF, with a significant increase in both perseverative and non perseverative errors during the WCST. On the other hand the PD group showed a selective increase of non perseverative errors, without reaching significant between group difference. CONCLUSION: The CD group appears to have greater deficits in EF with a pattern of prefrontal dysfunction.

Estudio comparativo de las funciones ejecutivas entre pacientes con enfermedad de Parkinson y pacientes con enfermedad degenerativa cerebelosa / Comparison study of executive functions in Parkinson's disease and degenerative cerebellar disease's patients

OBJETIVO: Comparar el rendimiento en tareas de función ejecutiva (FE) en sujetos con enfermedad de Parkinson (EP) leve a moderada (Hoehn y Yahr <3) no dementes y en sujetos con enfermedad degenerativa cerebelosa pura (EC), a fin de evaluar el eventual rol diferencial de los ganglios basales y el cerebelo en esa función. MÉTODO: Se evaluaron 14 pacientes con EP y 14 con EC apareados por sexo, educación, duración de enfermedad y MMSE, mediante tests neuropsicológicos estándar y el test de Wisconsin [WCST]). Se compararon puntajes Z promedio de cada grupo mediante prueba de "t" para muestras independientes. RESULTADOS: El grupo EC rindió significativamente menos en pruebas de atención y FE presentando errores perseverativos y no perseverativos durante el WCST. El grupo EP mostró aumento significativo de errores no perseverativos en relación al estándar esperado, sin alcanzar diferencias significativas con el grupo EC. CONCLUSION: el grupo EC mostró defectos significativamente mayores en tareas de FE exhibiendo un patrón de disfunción prefrontal.

OBJECTIVE: To compare executive functions (EF) in non-demented mild to moderate Parkinson's disease (PD) (Hoehn and Yahr <3) and pure degenerative cerebellar disease (CD) in order to evaluate the relative contribution and differential role of basal ganglia and cerebellum in those functions. METHOD: 14 patients with PD and 14 patients with CD matched by sex, education, disease's duration and MMSE were selected. A standardized neuropsychological battery and the Wisconsin Card Sorting Test (WCST) were administered. Z scores were compared for both groups through t-test for independent samples were used. RESULTS: The cerebellar group showed significant lower performance in measures of attention and EF, with a significant increase in both perseverative and non perseverative errors during the WCST. On the other hand the PD group showed a selective increase of non perseverative errors, without reaching significant between group difference. CONCLUSION: The CD group appears to have greater deficits in EF with a pattern of prefrontal dysfunction.

Normal anatomy of the developing fetal brain. Ex vivo anatomical-magnetic resonance imaging correlation.

Fetal brain Magnetic Resonance Imaging (MRI) is a new technique of growing interest, with a high potential to detect prenatal central nervous system abnormalities. This requires an accurate knowledge of the normal morphological sequence of brain development. In this paper we studied the cortical development of post-mortem normal fetal brains, correlating MRI estimations of fetal age with in vitro anatomical and anthropometric measurements. Ten post-mortem fetal heads were submitted to MRI. Maturational state of sulci and gyri and gray-white matter differentiation were analysed in the MRIs and by dissection of the brains. The findings were correlated with the previously estimated ages of the fetuses, which varied between 17 and 38 weeks. Consistency between methods was assessed employing intraclass correlation coefficient and Bland-Altman plots, with a 95% confidence interval. Estimations of fetal age obtained by MRI were very similar to those achieved by anthropometric measurements or by considering anatomical parameters. Gyral development proved to be more precise than gray-white matter differentiation for this purpose. Fetal MRI proved to be as reliable as the macroscopic anatomical examination for depicting normal cortical developmental sequence and age, suggesting that this technique may be a suitable option for achieving precise information about the morphology of human brains along the gestational period.

Periventricular nodular and subcortical neuronal heterotopia in adult epileptic patients.

Developmental malformations are brain abnormalities that occur during embryogenesis. Neuronal migration disorders, including heterotopic lesions, constitute one type of such abnormalities. The aim of the study was to compare the epileptic clinical patterns of patients with periventricular nodular heterotopia (PNH) (G1) with those affected by subcortical heterotopia (SCH) (G2) looking for differences between both groups which, eventually, might suggest the type of the underlying malformation. The variables studied in both groups were: type of the heterotopia depicted on MRI studies, sex, age, age at seizure onset, annual seizure frequency, localization of the ictal symptomatogenic zone, characteristics of the EEG, other associated anomalies on the magnetic resonance images (MRI) besides the heterotopia, and response to treatment. The only difference found between both groups was the type of heterotopia as shown by MRI studies. The other assessed variables did not significantly (p>0.05) differ between groups. No differences in the clinical features characterizing epilepsy could be found in patients with PNH or SCH, being the images the only tool able to differentiate them.

A new type of anti-ganglioside antibodies present in neurological patients.

High titers of anti-GA1 antibodies have been associated with neurological syndromes. In most cases, these antibodies cross-react with the structurally related glycolipids GM1 and GD1b, although specific anti-GA1 antibodies have also been reported. The role of specific anti-GA1 antibodies is uncertain since the presence of GA1 in the human nervous system has not been clarified. A rabbit was immunized with GD1a and its sera were screened for antibody reactivity by standard immunoassay methods (HPTLC-immunostaining and ELISA). Anti-GD1a antibodies were not detected but, unexpectedly, anti-GA1 IgG-antibodies were found. Antibody binding to GA1 was inhibited by soluble GA1 but also by GD1a. These results indicate that the rabbit produced antibodies that recognize epitopes present on the glycolipids, that are absent or not exposed on solid phase adsorbed GD1a. We investigated the presence of these unusual anti-ganglioside antibodies in normal and neurological patient sera. Approximately, 10% of normal human sera contained low titer of specific anti-GA1 IgG-antibodies but none of them recognized soluble GD1a. High titers of IgG-antibodies reacting only with GA1 were detected in 12 patient sera out of 325 analyzed. Of these, 6 sera showed binding that was inhibited by soluble GD1a and four of them also by GM1. This new type of anti-ganglioside antibodies should be considered important elements for understanding of the pathogenesis of these diseases as well as their diagnosis.