Functional mapping of the lower urinary tract by epidural electrical stimulation of the spinal cord in decerebrated cat model.

Several neurologic diseases including spinal cord injury, Parkinson's disease or multiple sclerosis are accompanied by disturbances of the lower urinary tract functions. Clinical data indicates that chronic spinal cord stimulation can improve not only motor function but also ability to store urine and control micturition. Decoding the spinal mechanisms that regulate the functioning of detrusor (Detr) and external urethral sphincter (EUS) muscles is essential for effective neuromodulation therapy in patients with disturbances of micturition. In the present work we performed a mapping of Detr and EUS activity by applying epidural electrical stimulation (EES) at different levels of the spinal cord in decerebrated cat model. The study was performed in 5 adult male cats, evoked potentials were generated by EES aiming to recruit various spinal pathways responsible for LUT and hindlimbs control. Recruitment of Detr occurred mainly with stimulation of the lower thoracic and upper lumbar spinal cord (T13-L1 spinal segments). Responses in the EUS, in general, occurred with stimulation of all the studied sites of the spinal cord, however, a pronounced specificity was noted for the lower lumbar/upper sacral sections (L7-S1 spinal segments). These features were confirmed by comparing the normalized values of the slope angles used to approximate the recruitment curve data by the linear regression method. Thus, these findings are in accordance with our previous data obtained in rats and could be used for development of novel site-specific neuromodulation therapeutic approaches.

Rigidez de descerebración transitoria en el contexto de hipoxemia y administración de propofol, midazolamflumacenilo y remifentanilo-naloxona / No disponible

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Spontaneous Intracranial Epidural Hematoma Originating from Dural Metastasis of Hepatocellular Carcinoma

Spontaneous intracranial epidural hematoma (EDH) due to dural metastasis of hepatocellular carcinoma is very rare. A 53-year-old male patient with hepatocellular carcinoma, who was admitted to the department of oncology, was referred to department of neurosurgery because of sudden mental deterioration to semicoma with papillary anisocoria and decerebrate rigidity after transarterial chemoembolization for hepatoma. Brain computed tomography (CT) revealed large amount of acute EDH with severe midline shifting. An emergent craniotomy and evacuation of EDH was performed. Active bleeding from middle cranial fossa floor was identified. There showed osteolytic change on the middle fossa floor with friable mass-like lesion spreading on the overlying dura suggesting metastasis. Pathological examination revealed anaplastic cells with sinusoidal arrangement which probably led to spontaneous hemorrhage and formation of EDH. As a rare cause of spontaneous EDH, dural metastasis from malignancy should be considered.

Receptores de la serotonina que inhiben el tono simpático vasopresor en la rata descerebrada y desmedulada / Role of serotonin receptors in vascular tone in the pithed rat

Serotonin (5-hydroxytryptamine; 5-HT) has been shown to produce vascular sympatho-inhibition in a wide variety of isolated blood vessels by activation of prejunctional 5-HT1 receptors. After considering the mechanisms involved in modulating neuroeffector transmission, the present review analyzes the experimental findings identifying the pharmacological profile of the 5-HT receptors that inhibit the sympathetically-induced vasopressor responses in pithed rats. Thus, 5-HT-induced sympatho-inhibition has been shown to be: (i) unaffected by physiological saline or by the selective antagonists ritanserin (5-HT2), MDL72222 (5-HT3) or tropisetron (5-HT3/4); (ii) blocked by methysergide, a non-selective 5-HT1/2 receptor antagonist; and (iii) potently mimicked by 5-carboxamidotryptamine (5-CT), a non-selective 5-HT1 receptor agonist, as well as by the selective agonists 8-OH-DPAT (5-HT1A), indorenate (5-HT1A), CP93,129 (5-HT1B), and sumatriptan (5-HT1B/1D). These findings show the involvement of prejunctional 5-HT1 receptors. With the use of selective antagonists, it has been shown subsequently that the sympatho-inhibition induced by indorenate, CP93, 129, and sumatriptan was selectively antagonized by WAY100635 (5-HT1A), cyanopindolol (5-HT1A/1B), and GR127935 (5-HT1B/1D), respectively. These results demonstrate that the 5-HT1 receptors mediating sympatho-inhibition on the systemic vasculature of pithed rats resemble the pharmacological profile of the 5-HT1A, 5-HT1B, and 5-HT1D subtypes.

Crisis cerebelosas: ¿se puede hablar de ellas? / Cerebellar seizures: can we speak of such a thing?

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Coma prolongado por síndrome de embolia grasa tras fractura de fémur / Prolonged coma due to fat embolism syndrome after fracture of the femur

Un varón de 24 años presentó, tras sufrir fracturadiafisaria de fémur por accidente de moto, un deterioroneurológico progresivo con tomografía computerizadacerebral normal, que obligó a la intubación endotraqueale instauración de ventilación mecánica. Evolucionóhacia un cuadro de sepsis y disfunción multiorgánica,que se resolvió. La resonancia magnética cerebralmostró imágenes sugestivas de embolismo graso y seinvestigó la presencia de foramen oval permeable. Elpaciente permanecía en estado de coma vigil tres mesesdespués del accidente.Tras descartar otras causas más probables, el deterioroneurológico tras un traumatismo con fracturas, debehacernos sospechar un embolismo graso. Las manifestacionesneurológicas del síndrome de embolia grasa tienen,por lo general, buen pronóstico. Los casos gravessugieren una embolización cerebral (paradójica) masivay se asocian a la existencia de un foramen oval permeable.El diagnóstico precoz permite identificar al pacientecomo de alto riesgo para el tratamiento quirúrgico definitivo.Se ha descrito una evolución positiva con el cierrepreoperatorio del foramen oval

A 24-year-old male came to the emergency departmentwith a diaphyseal fracture of the femur resultingfrom a motorcycle accident. Neurological deteriorationwas progressive, although a computed tomography scanwas normal. Endotracheal intubation for mechanicalventilation was necessary. His condition progressed tosepsis and multiorgan failure before resolving. Magneticresonance images of the brain suggested a fat embolism.The presence of a patent foramen ovale was investigated.The patient remained in a state of coma vigil for 3months after the accident.After ruling out other more likely causes of neurologicaldeterioration after trauma with fractures, fat embolismshould be suspected. The prognosis for the neurologicalmanifestations of fat embolism syndrome aregenerally good. Severe cases suggest massive (paradoxical)embolization of the brain and are associated with apatent foramen ovale. Early diagnosis will identify thepatient at high surgical risk. A favorable course and outcomehave been reported with preoperative closure of theforamen ovale

Incidência de cervicalgia e alterações posturais do segmento cefálico em pacientes portadores de DTM. Estudo retrospectivo / Incidence of cervicalgia and head postural changes in temporomandibular disorders patients. Retrospective analysis

Os autores estudaram a incidência de cervicalgia e de alterações posturais em pacientes portadores de DTM. Foram avaliados 307 pacientes (64 homens e 243 mulheres) no período de 1996 a 2002. Dos pacientes avaliados, 86,97% apresentaram dor na região cervical, 260 (84,69%) apresentaram anteriorização do segmento cefálico e 254 (82,74%) apresentaram protrusão dos ombros

Effect of Enflurane on the Baroreflex Control of Heart Rate in Decerebrate Rats

Volatile anesthetics alter the arterial baroreflex (BRX) but its mechanisms are poorly understood. This study was designed to determine the effect of 1 and 2 minimal alveolar concentrations (MAC) of enflurane on the BRX parameters in unanesthetized brain stem-intact and decerebrate rats. Under enflurane anesthesia, the femoral artery and both femoral vein were catheterized for pressor (phenylephrine) and depressor (nitroprusside) drug delivery and continuous blood pressure measurements. Decerebration was performed at midcollicular level. BRX tests were performed in 3 time periods; before enflurane (conscious brain-intact), during 1 or 2 MAC enflurane exposure 1 hour after a sham operation or a decerebration operation, and 2 hours after the termination of enflurane (zero enflurane). Mean arterial pressure (MAP) and heart rate (HR) were fitted to a sigmoid logistic equation, the Boltzman equation. The curve of best fit was obtained with a computer program. 1 MAC and 2 MAC of enflurane shifted MAP-HR baroreflex curves to the left in the all groups and significantly attenuated the baroreflex range. The slope of conscious intact period and zero enflurane period of each group did not change significantly, but during the enflurane period the slope was significantly lowered. Enflurane depressed the baroreflex sensitivity (slope) and the HR range in a similar dose-dependant manner in both brain stem-intact and decerebrate rats. Such results draw into question whether the suprapontine sites contribute to enflurane's actions on cardiovascular autonomic regulation.

Diagnóstico de la muerte encefálica mediante ultrasonografía Doppler transcraneal en un modelo experimental de donante de órganos para trasplante / Diagnosis of brain death by transcranial doppler ultrasonography in an experimental organ donor model

OBJETIVO: Crear un modelo experimental de donante de órganos para trasplante y validarlo mediante el estudio ultrasonográfico de la velocidad del flujo sanguíneo intracraneal. MATERIAL Y MÉTODO: Se emplearon 10 conejos blancos de Nueva Zelanda divididos en un grupo control y un grupo experimental. En el segundo se provocó la muerte encefálica (ME) por un mecanismo de hipertensión intracraneal (HTIC) severa. El diagnóstico de la ME se basó en la exploración clínica y en el estudio de la velocidad del flujo sanguíneo intracraneal mediante ultrasonografía Doppler transcraneal. Ambas exploraciones fueron realizadas en todos los animales en situación basal y experimental. RESULTADOS: La exploración clínica y la velocidad del flujo sanguíneo intracraneal fueron normales en los animales del grupo control tanto en situación basal como experimental. En el grupo experimental también se obtuvieron resultados normales en ambos casos en situación basal, pero tras provocar HTIC aparecieron los signos clínicos diagnósticos de la ME (ausencia de respuesta a estímulos dolorosos en el territorio de un par craneal, ausencia de reflejos troncoencefálicos y apnea) y la velocidad del flujo sanguíneo en las arterias de la base del cráneo adoptó un patrón denominado "espigas sistólicas", que es característico de la parada circulatoria cerebral. CONCLUSIONES: Los resultados obtenidos en la exploración clínica y ultrasonográfica en nuestro estudio suponen la validación adecuada de este modelo experimental de ME y demuestran que la ultrasonografía Doppler transcraneal es útil en el diagnóstico de la ME en el conejo. (AU)

Hipertensión intracraneal y muerte encefálica / Intracranial hypertension and brain death

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Two Cases of Acute Encephalopathy with Thalamotegmental Involvement and Remained Motor Dysfunction in Infants / 대한소아신경학회지

Acute encephalopathy with thalamotegmental involvement occurs in infants and young children and is thought to be a postviral or postinfectious brain disease. This disease is preceded for several days by fever and symptoms of upper respiratory infection. The symptoms are followed by the rapid evolution of stupor and coma, associated with generalized seizures and decerebrate rigidity. In this disease, the computed tomography (CT) or brain magnetic resonance imaging demonstrate symmetrical focal lesions in the thalami and brainstem tegmentum. We report two cases of acute encephalopathy with thalamotegmental involvement and remaining motor dysfunction in infants.

A Case of Acute Encephalopathy with Thalamotegmental Involvement / 대한소아신경학회지

Acute encephalopathy with thalamotegmental involvement is characterized by the rapid evolution of stupor and coma, associated with generalized seizures and decorticate or decerebrate rigidity without focal neurologic or meningeal irritation signs. The magnetic resonance findings in a 6-year-old patient with neurologic abnormalities demonstrate bilateral symmetrical high signal intensity lesions involving both the thalami and the tectum in axial T2-weighted image. We report a case of acute encephalopathy with thalamotegmental involvement.

Lack of integrative control of body temperature after capsaicin administration

BACKGROUND: Body temperature is usually regulated by opposing controls of heat production and heat loss. However, systemic administration of capsaicin, the pungent ingredient of hot peppers, facilitated heat production and heat loss simultaneously in rats. We recently found that the capsaicin-induced heat loss and heat production occur simultaneously and that the biphasic change in body temperature is a sum of transient heat loss and long-lasting heat production. Moreover, suppression of the heat loss response did not affect capsaicin-induced heat production and suppression of heat production did not affect capsaicin-induced heat loss. These observations suggest the independent peripheral mechanisms of capsaicin-induced thermal responses. Thus, the capsaicin-induced thermal responses apparently lack an integrated control. METHODS: Male Wistar rats were maintained at an ambient temperature of 24 1 degrees C on a 12 h on-off lighting schedule at least for two weeks before the experiments. They were anesthetized with urethane (1.5 g/kg, i.p.) and placed on a heating pad, which was kept between 29 and 30 degrees C. Skin temperature(Ts) was measured with a small thermistor, which was taped to the dorsal surface of the rat's tail, to assess vasoactive changes indirectly. Colonic temperature(Tc) was measured with another thermistor inserted about 60 mm into the anus. O2 consumption was measured by the open-circuit method, and values were corrected for metabolic body size (kg0.75). Capsaicin (Sigma) was dissolved in a solution comprising 80+ACU- saline, 10+ACU- Tween 80, and 10+ACU- ethanol, and injected subcutaneously at a dose of 5 mg/kg. Each rat received a single injection of capsaicin because repeated administration of capsaicin renders an animal insensitive to the subsequent administration of capsaicin. Laminectomy was performed at the level of the first and second cervical vertebrae to expose the cervical spinal cord for sectioning. The brain was transected at 4-mm rostral from the interaural line with an L-shaped knife. RESULTS: After administration of capsaicin, O2 consumption increased from 13.5 0.4 mL/min/kg0.75 at 0 min to a peak of 15.9 0.4 mL/min/kg0.75 at 71 min and gradually declined but remained higher than the basal value until the end of the 4-h observation period. Ts also immediately increased from 27.7 0.2 degrees C to 31.9 0.3 degrees C at 39 min, and it returned to the baseline level within 90 min after the capsaicin administration. Tc initially decreased from 37.1 0.1 degrees C to 36.8 0.2 degrees C at 43 min and then gradually increased over the baseline level and remained at 37.6 0.2 degrees C until the end of the experiment. In spinalized rats, the capsaicin-induced increases in O2 consumption was largely attenuated, while the basal O2 consumption was similar to that of control rats. The basal Ts of spinalized rats was 32.4 0.3 degrees C, which was higher than that of control rats. Capsaicin increased Ts by less than 1 degree C, and Tc did not change after the capsaicin administration. O2 consumption of decerebrated rats was statistically higher than that of control rats after the injection of capsaicin. However, capsaicin did not increase Ts, showing a lack of a vasodilatory response. Decerebration between the hypothalamus and midbrain prevented the capsaicin-induced heat loss but not the heat production response. CONCLUSION: These results show that the capsaicin-induced heat production and heat loss are controlled separately by the brainstem and by the forebrain, respectively, and suggest that the body temperature regulation is performed without an integrative center.

A Case of Acute Encephalitis with Thalamotegmental Involvement / 대한소아신경학회지

Acute encephalitis with thalamotegmental involvement in infants and children was reported in Japan, 1995. This encephalitis was preceded for several days by fever and symptoms of upper respiratory infection. These symptoms were followed by the rapid evolution of stupor and coma, associated with generalized seizures and decorticated and decerebrate rigidity without focal neurologic or meningeal signs. The prognosis was generally poor. We have experienced a case of acute encephalitis; the child had three days of fever before the hospitalization and convulsion and deteriorated mental change into a semicomatous state had developed. The patient was diagnosed as acute encephalitis with thalamotegmental involvement by magnetic resonance imaging.

Cardiovascular adjustments in limb retraction provoked by noxious stimulation in decerebrate and spinal cats: evidence for a somatotopic organization

Arterial blood pressure, heart rate and iliac blood flow were continuously recorded in 61 adult cats and their alteration induced by noxious stimulation of the interdigital spaces of the four limbs was studied in intact (anesthetized) and in decerebrate and spinal preparations. Noxious stimulation of any limb in the decerebrate animals provoked retraction 61 percent of the times and an increase of blood pressure and heart rate in approximately 80 percent of the stimulations. Stimulations of a hindlimb provoked an increase of blood flow in the same limb in about 80 percent of the stimulations, due to active vasodilation. Contralateral stimulation provoked as smaller increase of blood flow but with an increase in vascular resistance, indicating some degree of vasoconstriction. Stimulation of the forelimbs induced small increases of blood flow in the hindlimbs but the calculated vascular resistance was higher than the basal values, also indicating vasoconstriction. Neuromuscular blockade with gallamine did not affect the increase of hindlimb blood flow, suggesting a central regulation of the intricate distribution of blood to the limbs...

Clinical Analysis of Traumatic Hemorrhage in Child's Basal Ganglia: Eight Cases

Recently, the detection of traumatic intracerebral hematoma has been greatly expedited by the advent of computed tomography. However, traumatic basal ganglia hemorrhage(TBGH) in child have remained rare. The authors obtained following results with analysis of clinical features and outcome in 8 cases of child's TBGH who had been treated at the department of neurosurgery, chonnam university hospital from January 1984 to December 1986. 1) Age distribution was ranged from 3 to 9 years with an average age 5.1 years and 5 were males and 3 were females. 2) Blow of site of the head were right frontal 3, left frontal 3, right parietal 1 and right temporal 1. However, hematoma in the basal ganglia occurred 6 in the left and 2 in the right. 3) On admission, the consciousness level appeared 2 cases in drowsy state(GCS 13), 3 cases in stuporous state(GCS 8,9) and 3 cases in semicomcatose state(GCS 5,7). 4) CT findings of TBGH were classified into 3 types; Type I; spotty type, Type II; moderate type and Type III : massive type. The number of patients was 4 in type I, 2 in type II and 2 in type III. 5) Neurological examination revealed contralateral hemiparesis to the hematoma in all cases(8), facial nerve palsy in 3 cases, motor aphasia in 4 cases and decerebrate rigidity in 2 cases. 6) Of all cases (8), conservative treatment were done in 5 and surgical treatment in 3. As regards the outcome of all cases (8), showed good recovery in 3, moderate disabilety in 2 and death in 3. It was concluded that the first regimen to be chosen in the management of TBGH in child was medical treatment. The patient of moderately disturbed conseionsness would be successfully managed by conservative treatment. The indication for surgery should be restricted to such cases in which the consciouness status were getting worse in spite of active conservative treatment.

Cardiovascular regulation in the acute decerebrate rat

Male Wistar rats were decerebrated at precollicular level, by aspiration under ether anaesthesia. The experiments employed rats instrumented for chronic electrocardiogram (ECG) recordings or mean blood pressure (MBP) and heart rate (Hr) determination. Immediately after surgery, decerebrate (D) and sham operated (SO) animals presented a small and ismilar increase in their HR. Three and a half hours after surgery, SO group presented a normal HR, whilst D animals continued to show an increas ein their HR up to 4.5 h, when it stabilized. Twenty four hours after surgery both groups presented similar MBP (D:110ñ6; SO:108ñ11; SO:335ñ5 beats/min). The blockade of parasympathetic tonus induced significant increases in the HR of both groups, withou major changes in their MBP. Beta-adrenergic blockade reduced HR of both groups, bringin HR of D almost to control level. Simultaneously there was a reduction in MBP of D but not of SO animals. When parasympathetic blockade was superimposed to beta-adrenergic blockade, there was a significant increase in HR of SO, but not of D or in MBP of both groups. Thus we conclude that the decerebrate rat presents normal MBP with simultaneous tachycardia mainly caused by increased sympathetic outflow to the heart (AU)

Cardiovascular regulation in the acute decerebrate rat

Male Wistar rats were decerebrated at precollicular level, by aspiration under ether anaesthesia. The experiments employed rats instrumented for chronic electrocardiogram (ECG) recordings or mean blood pressure (MBP) and heart rate (Hr) determination. Immediately after surgery, decerebrate (D) and sham operated (SO) animals presented a small and ismilar increase in their HR. Three and a half hours after surgery, SO group presented a normal HR, whilst D animals continued to show an increas ein their HR up to 4.5 h, when it stabilized. Twenty four hours after surgery both groups presented similar MBP (D:110ñ6; SO:108ñ11; SO:335ñ5 beats/min). The blockade of parasympathetic tonus induced significant increases in the HR of both groups, withou major changes in their MBP. Beta-adrenergic blockade reduced HR of both groups, bringin HR of D almost to control level. Simultaneously there was a reduction in MBP of D but not of SO animals. When parasympathetic blockade was superimposed to beta-adrenergic blockade, there was a significant increase in HR of SO, but not of D or in MBP of both groups. Thus we conclude that the decerebrate rat presents normal MBP with simultaneous tachycardia mainly caused by increased sympathetic outflow to the heart