En esta sección se ponen a disposición de todos los usuarios y pacientes, una lista de publicaciones relacionadas con la Neurocirugía en los que han participado activamente miembros del equipo médico de la Unidad de Neurocirugía
Análisis comparativo de la historia clínica y la polisomnografía en la patología del sueño. Relevancia diagnóstica de la polisomnografía
J. Pastor, J. Fernández-Lorente, B. Ortega, J.M. Galán
The incidence of associate pathologies has been studied during the sleep, as well as the diagnostic efficiency of the clinical history. Patients and methods. Patients (n= 136) remitted by diverse services, have been studied. It has been carried out a complete polysomnography, as well as other supplementary studies (anxiety and depression tests, excessive daytime sleepiness Epworth’ s test, EEG and sleep notebook). Results. The most common symptom turned out to be the primary snores, followed by the excessive daytime sleepiness and apneas. The results of the excessive daytime sleepiness Epworth’ s test and the anxiety and depression tests were not useful to differ among pathologies, not even between pathologies and patients with normal sleep. The percentage of diagnosis of suspicion confirmed by the polysomnography was of 39.7%, while in 11% of the total of patients it was observed the existence of more than a pathology of the sleep. In 49.3% of the cases the polysomnographic diagnosis was completely different from the diagnosis of suspicion. Among the patients with clinic suspicion of apnoea, in 48.3% of the cases the existence of the same one was verified, although in 14.6% it was associated with other pathologies. In 51.7% of the patients it was not possible to confirm this pathology. Conclusions. The clinical history is not enough for the diagnosis of the pathologies of the sleep. On the other hand, the existence of associate pathologies diminishes the value of several ‘screening-methods’. Therefore, it is fundamental to carry out a complete polysomnography in all the patients that present any sleep disorder on the part of doctors that approach the problem of the sleep in a global way and not only thinking in the possible existence of syndrome of sleep apnoea. [REV NEUROL 2001; 32: 22-9: www.revneurol.com/3201/k010022.pdf]
Palabras claves. Apnoea. Epworth’ s test. Excessive daytime sleepiness. Periodic movements of the extremities. Polysomnography. Sleep.
Modelo matemático de la acción dual de la proteína G sobre la corriente de Ca2+ en neuronas identificadas del caracol Helix aspersa
The effect of the dopamine on the calcium current of identified cells of the snail Helix aspersa consists on an initial decrease, followed by a subsequent increase when the drug is removed. It had been previously demonstrated that this effect is mediated by a G protein, supposing that the decrease of the current would be mediated by the Gα subunit, while the increase would be produced by the Gβγ subunit. Objective. A mathematical model has been developed with the object to test if the hypothesis of the dual action of the G protein could explain the experimental results. Material and methods. It has been recording by means of the ‘patch-clamp’ (whole cell) in identified cells of snail. On the other hand, it has been developed a mathematical model of the calcium current using a Hodgkin-Huxley model, and a simulation of the action of the G protein on this current. Results. Adjusting the kinetic parameters of the channel by means of the experimental data, it has reproduced in a faithful way the behavior of the calcium current. The simulation of the action of dopamine reproduces the decrease and increase of the current by means of the serial action of the G protein’s subunits. Conclusion. Although a mathematical model cannot demonstrate the logic necessity of the hypotheses on that is based, it is unequivocally demonstrated that the hypothesis is fully compatible with experimental results [REV NEUROL 1999; 28: 745-51].
Palabras claves. Calcium current. G-protein. Helix aspersa. Mathematical model.
Plasma albumin induces calcium waves in rat cortical astrocytes
Angel Nadal, Esther Fuentes, J. Pastor, Peter McNaugthon
Changes in intracellular calcium were monitored in cultured cortical astrocytes stimulated with albumin. Albumin elicited intracellular calcium mobilisation from intracellular stores, inducing repetitive intracellular calcium oscillations. The oscillations were not blocked by ryanodine, a blocker of the Ca-induced Ca release mechanism, and the release occurred from the same store as is accessed by glutamate and bradykinin, both of which release calcium by an IP3-dependent mechanism. Calcium signals induced by albumin appear therefore to occur via a pure IP3-dependent mechanism. When albumin was applied to confluent monolayers of astrocytes, the oscillations in individual cells were initially unsynchronised, but after several minutes of application, the Ca21 oscillations were observed to synchronise and spread through the astrocyte network as a wave. These intercellular calcium waves were inhibited by the gap junction blocker halothane. Using the fluorescence recovery after photobleaching (FRAP) technique, we demonstrate that the development of propagated waves with prolonged exposure to albumin does not result from an increase in cell coupling. The development of calcium waves on exposure to albumin may be important in the formation
of glial scars in the CNS after breakdown of 1997.- 1997 Wiley-Liss, Inc.
Mecánica cuántica y cerebro: una revisión crítica
Jesús Pastor Gómez
Theories about consciousness are in an initial state of development. In the recent past, diverse theories have been proposed to explain the phenomenon of the consciousness using the Quantum Mechanics (QM) as a fundamental tool. Here, we criticize some of these theories in the light of the current knowledge in neuroscience. Development. The QM theories of consciousness by John Eccles, Dana Zohar and Roger Penrose are discussed. For a better understanding of these theories, some physical principles of the quantum formalism are firstly introduced. We then expose these theories in the authors’ original formalism and discuss them from a neuroscientist point of view. Discussion. As currently exposed, the three QM theories of consciousness suffer from important neuroscientist concerns. It is not necessary the use QM to explain different aspects of brain function such as consciousness, which would be better understood using tools from the neurosciences. [REV NEUROL 2002; 35: 87-94]
Palabras claves. Axolema. Brain function. Consciousness. Microtubules. Principle of uncertainty. Superposition. Synapses.
Pseudoquiste epicraneal gigante tras la desconexión de un sistema de derivación ventriculoperitoneal
Rodrigo Carrasco-Moro, Diego Chillón-Medina, José M. Pascual-Garvi, Rebeca Conde-Sardón, Marta Navas-García, Rafael G. Sola
La malfunción de los dispositivos de derivación de líquido cefalorraquídeo (LCR) suele manifestarse clínicamente mediante un síndrome de hiperten- sión intracraneal [1,2]. Sin embargo, debido a la presencia de determina dos mecanismos de compensación, puede permanecer clínicamente silente o adoptar formas de presentación clínica atípicas, caracterizadas por la ausencia de dilatación ventricular . A continuación presentamos el ejemplo de un paciente adulto portador de una derivación ventriculoperitoneal, cuya malfunción produjo un acúmulo progresivo de LCR en la zona subgaleal como mecanismo compensador frente al desarrollo de hidrocefalia.
Palabras claves. Hidrocefalia, Líquido Cefaloraquideo, Hipertensión arterial.