Cortico-Striatal Oscillations Are Correlated to Motor Activity Levels in Both Physiological and Parkinsonian Conditions.

Oscillatory neural activity in the cortico-basal ganglia-thalamocortical (CBGTC) loop is associated with the motor state of a subject, but also with the availability of modulatory neurotransmitters. For example, increased low-frequency oscillations in Parkinson's disease (PD) are related to decreased levels of dopamine and have been proposed as biomarkers to adapt and optimize therapeutic interventions, such as deep brain stimulation. Using neural oscillations as biomarkers require differentiating between changes in oscillatory patterns associated with parkinsonism vs. those related to a subject's motor state. To address this point, we studied the correlation between neural oscillatory activity in the motor cortex and striatum and varying degrees of motor activity under normal and parkinsonian conditions. Using rats with bilateral or unilateral 6-hydroxydopamine lesions as PD models, we correlated the motion index (MI)-a measure based on the physical acceleration of the head of rats-to the local field potential (LFP) oscillatory power in the 1-80 Hz range. In motor cortices and striata, we observed a robust correlation between the motion index and the oscillatory power in two main broad frequency ranges: a low-frequency range [5.0-26.5 Hz] was negatively correlated to motor activity, whereas a high-frequency range [35.0-79.9 Hz] was positively correlated. We observed these correlations in both normal and parkinsonian conditions. In addition to these general changes in broad-band power, we observed a more restricted narrow-band oscillation [25-40 Hz] in dopamine-denervated hemispheres. This oscillation, which seems to be selective to the parkinsonian state, showed a linear frequency dependence on the concurrent motor activity level. We conclude that, independently of the parkinsonian condition, changes in broad-band oscillatory activities of cortico-basal ganglia networks (including changes in the relative power of low- and high-frequency bands) are closely correlated to ongoing motions, most likely reflecting he operations of these neural circuits to control motor activity. Hence, biomarkers based on neural oscillations should focus on specific features, such as narrow frequency bands, to allow differentiation between parkinsonian states and physiological movement-dependent circuit modulation.

Sulfonamido-aryl ethers as bradykinin B1 receptor antagonists.

The synthesis and identification of sulfonamido-aryl ethers as potent bradykinin B1 receptor antagonists from a approximately 60,000 member encoded combinatorial library are reported. Two distinct series of compounds exhibiting different structure-activity relationships were identified in a bradykinin B1 whole-cell receptor-binding assay. Specific examples exhibit K(i) values of approximately 10nM.

La glomérulonefritis aguda en el niño / Acute glomerulonephritis in children

Se analiza una serie de 45 niños de 2 a 15 años, promedio 7,7 años con cuadro clínico e histológico de GNA, que fueron seguidos hasta por treinta meses. Se realizó en ellos dos estudios histológicos (ML, ME, IN) en biopsias practicadas al comienzo de la enfermedad (promedio 20 días) y la segunda a los 194 ó 590 días en promedio. En el estudio clínico se destaca la normalización del edema a los 8,8 días y la hipertensión a los 4,3 días. Sólo se obtuvo estreptococo betahemolítico en cuatro enfermos, lo que puede relacionarse con el tratamiento antibiótico recibido previamente por estos niños. En el examen de orina un alto porcentaje no presentó hematuria (44%) o proteinuria (49%) en el examen de ingreso y sólo 29,9% tuvo cilindruria. La albuminemia tuvo valores bajo lo normal en el 35,6% de los niños, alfa 2 globulina y gamaglobulina con valores normales en todos. El complemento C3 fue en promedio 41,3m% y sólo 3 enfermos tenían valores sobre 100mg%. Se describen las curvas de antiestreptolisina O (ASO) y STZ en estos niños y se destaca la necesidad de determinaciones seriadas tanto de C3 como ASO y STZ. En el análisis de 194 contactos se obtuvo sólo 5 frotis faríngeos y 10 cutáneos positivos a estreptococo betahemolítico e estafilococo. En el estudio histológico se encontró buena correlación entre la intensidad de las lesiones en microscopía de luz (ML) y microscopía electrónica (ME). En esta última se destaca en la primera biopsia que todos tenían depósitos inmunes intramembranosos segmentarios y 84% con depósitos en joroba. La segunda biopsia mostró una disminución apreciable de la intensidad de las lesiones a los 6 meses y en las realizadas en promedio a los 590 días se encontró ya tres casos que pueden considerarse normales desde el punto de vista histológico. Otros tres con lesiones...