Prevalencia del desarrollo de entesofito en la Protuberancia Occipital Externa en población de paraguayos / Prevalence of enthesophyte development in External Occipital Protuberance in Paraguayan population

Introducción.La Protuberancia Occipital Externa (POE) es una superficie convexa y lisa que tradicionalmente no presenta ningún tipo de irregularidades. La aparición de un entesofito en individuos ha llamado la atención de los investigadores. Objetivo.Determinar la prevalencia, longitud, edad y sexo de una exostosis en forma de gancho desarrollada a nivel de la POE. Metodología.Estudio observacional descriptivo realizado en radiografías laterales de cráneo de individuos jóvenes. De 5065 radiografías, 4017 radiografías cumplieron con los criterios. Se procedió a la detección de la presencia de un gancho óseo en la POE y su medición. Resultados.Se incluyeron personas de ambos sexos entre 13 a 45 años: 2902 mujeres y 1115 varones. De las 4017 radiografías observadas, el 67% presentó la excrecencia en la POE, con rangos desde 5 a 24 mm en longitud, 511 tenían una longitud de 5 mm o mayor, 903 entre 9 a 12 mm de longitud y 253 de 13 a 24mm. Se observó enmayor proporción en el sexo masculino que el femenino(68% vs 32%). En los individuos de 40 años y más, solo un paciente de sexo masculino mostró la presencia del entesofito. Conclusión.Se ha encontrado una alta frecuencia del desarrollo de una protuberancia ósea a nivel del POE en jóvenes y adultos jóvenesde sexo masculino. Este es el primer estudio de este tipo realizado en la población del Paraguay. Para comprender la razón del desarrollo de esta excrecencia ósea, es necesario ampliar el área de investigación. Palabras Clave:ganchos óseos;protuberancia; exostosis; entesopatía.

Introduction.The external occipital protuberance (EOP) is a smooth convex surface which commonly does not present any type of irregularities. The development of an enthesophyte in young population has attracted the attention of researchers. Objective.To determine the prevalence, size, age, and sex of individuals with bony projections that resembles a hook developed in EOP. Methodology.Descriptive observational study. 5065 lateral skull x-rays were observed. 4017 fulfilled all the criteria. The x-rays were reviewed for the presence of a bony excrescence in EOP, and they were measured. Results. From a both sexes population between 13 to 45 years old 2902 were female and 1115 were male. 67% X-rays presented the enthesophyte ranging from 5 ­24mm in length. 511 out of 1667 had an enthesophyte at or above 5 mm. There were 903 patients with an enthesophyte ranging from 9 ­12 mm in length and 254 had the protuberance ranging from 13 ­24 mm. Statistically significant range of 68% vs 32% between males and females were observed. From individuals of 40 years and above, just 1 male patient out of 32 showedthe enthesophyte. Conclusion.Significant association with the development of a bony protuberance at the POE in young and young adult male population has been found. This is the first study of this type in Paraguayan individuals. To expand the field of studies, future research is needed to better examine and understand the reason forthe development of this bony excrescence. Key words:bone hooks; protuberance;exostoses; enthesopathies.

Transaxonal degenerations of cerebellar connections: the value of anatomical knowledge / Degenerações transaxonais das conexões cerebelares: o valor do conhecimento anatômico

ABSTRACT Transaxonal degenerations result from neuronal death or the interruption of synaptic connections among neuronal structures. These degenerations are not common but may be recognized by conventional magnetic resonance imaging. Objective: The learning objectives of this review include recognition of the imaging characteristics of transaxonal degenerations involving cerebellar connections, the identification of potential encephalic lesions that can lead to these degenerations and correlation of the clinical manifestations with imaging findings that reflect this involvement. Methods: In this report, we review the neuroanatomical knowledge that provides a basis for identifying potential lesions that can result in these degenerations involving cerebellar structures. Results: Hypertrophic olivary degeneration results from an injury that interrupts any of the components of the Guillain-Mollaret triangle. In this work, we describe cases of lesions in the dentate nucleus and central tegmental tract. The crossed cerebellar diaschisis presents specific imaging findings and clinical correlations associated with its acute and chronic phases. The Wallerian degeneration of the middle cerebellar peduncle is illustrated by fiber injury of the pontine cerebellar tracts. A T2-hyperintensity in the dentate nucleus due to a thalamic acute lesion (in ventral lateral nuclei) is also described. Each condition described here is documented by MRI images and is accompanied by teaching points and an anatomical review of the pathways involved. Conclusion: Neurologists and radiologists need to become familiar with the diagnosis of these conditions since their presentations are peculiar and often subtle, and can easily be misdiagnosed as ischemic events, degenerative disease, demyelinating disease or even tumors.

RESUMO Degenerações transaxonais resultam da morte neuronal ou da interrupção de conexões sinápticas entre estruturas neurais. Essas degenerações não são comuns, mas podem ser reconhecidas por imagens de ressonância magnética convencional. Objetivo: Os objetivos de aprendizado desta revisão incluem o reconhecimento das características de imagem de degenerações transaxonais envolvendo conexões cerebelares, a identificação de possíveis lesões encefálicas que podem levar a essas degenerações e a correlação das manifestações clínicas com os achados de imagem que refletem esse envolvimento. Métodos: Neste artigo, revisamos conhecimentos neuroanatômicos que fornecem a base para identificar possíveis lesões que podem resultar nessas degenerações envolvendo estruturas cerebelares. Resultados: A degeneração olivar hipertrófica resulta de uma lesão que interrompe algum dos componentes do triângulo de Guillain-Mollaret. Neste trabalho, descrevemos casos de lesões no núcleo denteado e no trato tegmentar central. A diásquise cerebelar cruzada apresenta achados de imagem específicos e correlações clínicas associadas às suas fases aguda e crônica. A degeneração walleriana dos pedúnculos cerebelares médios é ilustrada pela lesão dos tratos pontino-cerebelares. Uma hiperintensidade em T2 do núcleo denteado devido a uma lesão talâmica aguda (no núcleo ventrolateral) também é descrita. Cada condição aqui descrita é documentada por imagens de ressonância magnética e é acompanhada por pontos didáticos e uma revisão anatômica das vias envolvidas. Conclusão: Neurologistas e radiologistas precisam estar familiarizados com o diagnóstico dessas condições, uma vez que suas apresentações são peculiares e frequentemente sutis, e podem ser facilmente equivocadamente diagnosticadas como lesões isquêmicas, doenças degenerativas, desmielinizantes, ou mesmo tumorais.

Neuralgia del Trigémino / Trigeminal neuralgia

Resumen La neuralgia del trigémino (NT) es una enfermedad cuya prevalencia es alta y corresponde a un porcentaje importante de neuralgias faciales; en donde las personas más afectadas son mayores de 50 años. Su manifestación clínica suele ser de cuadros de dolor facial severo y recurrentes, unilateral; en la distribución de una o más divisiones del nervio trigémino y no se explica con otro diagnóstico. El diagnóstico se basa en el cuadro clínico y usualmente no se encuentra déficit sensorial, sin embargo, si está presente se deben hacer neuroimágenes para descartar otras causas. En primera instancia está el manejo farmacológico. La carbamazepina se ha establecido como efectivo, llegando a producir un alivio del dolor dentro de las 24 horas. Cuando la farmacoterapia falla, se opta por la cirugía que se divide generalmente en dos: técnicas que destruyen la porción sensitiva del nervio; y la descompresión microvascular (DMV), que es la que tiene mejores resultados.

Abstract Trigeminal neuralgia is a disease whose prevalence is high and corresponds to a significant percentage of facial neuralgia; where the most affected people are over 50 years old. The clinical picture is usually of episodes of severe and recurring facial pain, unilateral; in the distribution of one or more divisions of the trigeminal nerve and this is not explained with another diagnosis. Diagnosis is based on the clinic and usually no sensory deficit is found, however, if present, neuroimaging should be done to rule out other causes. In the first instance is the pharmacological management. Carbamazepine has been established as effective, leading to pain relief within 24 hours. When pharmacological therapy fails, surgery is generally divided into two: techniques that destroy the sensitive portion of the nerve and microvascular decompression, which has the best results.

Síndrome de enclaustramiento: presentación de un caso / Locked-in syndrome: case report

El síndrome de enclaustramiento (Locked-in syndrome) es una entidad neurológica altamente discapacitante, producida por lesiones en la porción ventral de la protuberancia; de etiología principalmente vascular. Clínicamente se manifiesta por tetraplejía, anartria, preservación de la conciencia y capacidad de expresarse mediante movimientos oculares. Presentamos el caso de un paciente masculino de 33 años, transferido de otra institución de salud con un cuadro clínico progresivo y poco específico, caracterizado principalmente por deterioro del estado de conciencia, dificultad respiratoria, cefalea de intensidad moderada y vómitos. Mediante pruebas de imágenes se comprobó la presencia de un área de isquemia en la región irrigada por el sistema vertebrobasilar. Se realizó un enfoque diagnóstico y terapéutico invasivo de orden endovascular.

Locked-in syndrome is a highly disabling neurological entity, due to lesions in the ventral portion of the pons, mainly vascular etiology. Clinical features are quiadriplegia, anarthria, preservation of consciousness and the ability to express by ocular movements. We shown a case of a 33 years-old man, who was transfer from another institution with a progressive and poorly specific clinical manifestations, mainly characterized by diminishing of consciousness, breathing difficulty, headache and vomiting, with the presumptive diagnosis of central nervous system infection. We performed image diagnostic tests and they shown and ischemic feature in the region of the vertebrobasilar irrigation. It was perform an endovascular diagnostic therapeutic approach.

Propentofylline reverses delayed remyelination in streptozotocin-induced diabetic rats

Objective The diabetic state induced by streptozotocin injection is known to impair oligodendroglial remyelination in the rat brainstem following intracisternal injection with the gliotoxic agent ethidium bromide (EB). In such experimental model, propentofylline (PPF) recently showed to improve myelin repair, probably due to its neuroprotective, antiinflammatory and antioxidant effects. The aim of this study was to evaluate the effect of PPF administration in diabetic rats submitted to the EB-demyelinating model. Materials and methods Adult male rats, diabetic or not, received a single injection of 10 microlitres of 0.1% EB solution into the cisterna pontis. For induction of diabetes mellitus the streptozotocin-diabetogenic model was used (50 mg/kg, intraperitoneal route – IP). Some diabetic rats were treated with PPF (12.5 mg/kg/day, IP route) during the experimental period. The animals were anesthetized and perfused from 7 to 31 days after EB injection and brainstem sections were collected for analysis of the lesions by light and transmission electron microscopy. Results Diabetic rats injected with EB showed larger amounts of myelin-derived membranes in the central areas of the lesions and considerable delay in the remyelinating process played by surviving oligodendrocytes and invading Schwann cells after the 15th day. On the other hand, diabetic rats that received PPF presented lesions similar to those of non-diabetic animals, with rapid remyelination at the edges of the lesion site and fast clearance of myelin debris from the central area. Conclusion The administration of PPF apparently reversed the impairment in remyelination induced by the diabetic state. Arch Endocrinol Metab. 2015;59(1):47-53 .

Biomarcadores moleculares y su asociación con la supervivencia en niños con astrocitomas / Molecular biomarkers and their association with survival in children with astrocytomas

Los tumores del sistema nervioso central (SNC) representan los tumores sólidos más frecuentes en la edad pediátrica, los tumores del tallo suponen un 10% al 25%, y de ellos, los tumores difusos intrínsecos del puente (TDIP) presentan infiltración difusa en su patrón de crecimiento; el 95% de los niños mueren a causa de la enfermedad dentro de los tres primeros años con una mediana de supervivencia de 4 a 15 meses. Existen biomarcadores que se han puesto de manifiesto mediante técnicas de inmunohistoquímica. Objetivo: Determinar la asociación entre los marcadores tumorales Bcl2, CD133, p53 y Ki67 con la histología y la supervivencia de pacientes con tumor difuso intrínseco del puente. Pacientes y métodos: Se realizó un estudio ambilectivo, longitudinal, descriptivo de pacientes diagnosticados con TDIP en un período de 6 años con tipificación de los marcadores CD133, p53, Ki67, Bcl-2 mediante inmunohistoquímica, se analizó la asociación de dichos marcadores con la estirpe histológica y la supervivencia de los pacientes. Resultados: Se incluyeron en total 15 pacientes; por histología 11 (73%) tenían gliomas, y 4 (26.6%) presentaban tumores neuro ectodérmicos primitivos (TNEP). De los gliomas, 8 (72%) eran de bajo grado y 3 (28%) de alto grado, el marcador p53 estuvo sobre expresado en 8 de 14 pacientes (57%), p = 0.3802; Ki67 dio positivo en 7 de 14 pacientes (50%) p = 0.7363; el CD133 no presentó sobre expresión en ninguno de los enfermos, en tanto que Bcl-2 se encontró alterado en 9 de 14 sujetos (64%), p = 0.4858. La mediana de supervivencia en estos pacientes es de 13 meses. Conclusión: El biomarcador que muestra una asociación significativa con la supervivencia es Ki67, lo queda pie a la ideación de medidas terapéuticas de forma individualizada...

Dermatofibrosarcoma protuberans / Dermatofibrosarcoma protuberans

El dermatofibrosarcoma protuberans es un sarcoma de partes blandas, de malignidad intermedia y lento crecimiento. Afecta adultos jóvenes y a todas las etnias, aunque algunos trabajos observan cierta predilección por la etnia negra. La localizaciónhabitual es en tronco, extremidades proximales y en menor medida encabeza y cuello. El tratamiento de elección es la exéresis quirúrgica con preferencia por la cirugía micrográfica de Mohs. Presentamos seis pacientes con diagnóstico clínico e histopatológico de dermatofibrosarcoma protuberans, 2 mujeres y 4 varones de entre 24 a 52 años. Hasta el momento, 5 de ellos recibieron tratamientoquirúrgico (técnica micrográfica de Mohs en 4 pacientes y cirugía convencional en el restante). No se observaron recidivas en un período de seguimiento promediode 20 meses...

Brainstem cavernomas: a surgical challenge / Cavernomas de tronco: desafio cirúrgico

Objective: The authors show their experience with brainstem cavernomas, comparing their data with the ones of a literature review. Methods: From 1998 to 2009, 13 patients harboring brainstem cavernomas underwent surgical resection. All plain films, medical records and images were reviewed in order to sample the most important data regarding epidemiology, clinical picture, radiological findings and surgical outcomes, as well as main complications. Results: The mean age was 42.4 years (ranging from 19 to 70). No predominant gender: male-to-female ratio, 6:7. Pontine cases were more frequent. Magnetic resonance imaging was used as the imaging method to diagnose cavernomas in all cases. The mean follow-up was 71.3 months (range of 1 to 138 months). Clinical presentation was a single cranial nerve deficit, VIII paresis, tinnitus and hearing loss (69.2%). All 13 patients underwent resection of the symptomatic brainstem cavernoma. Complete removal was accomplished in 11 patients. Morbidity and mortality were 15.3 and 7.6%, respectively. Conclusions: Cavernomas can be resected safely with optimal surgical approach (feasible entry zone) and microsurgical techniques, and the goal is to remove all lesions with no cranial nerves impairment.

Objetivo: Os autores mostram sua experiência com cavernomas de tronco cerebral, comparando seus dados com os de uma revisão da literatura. Métodos: De 1998 a 2009, 13 pacientes com cavernoma de tronco cerebral foram submetidos a ressecção cirúrgica. Todos os filmes, prontuários e imagens foram revisados para exposição dos dados mais importantes, como epidemiologia, detalhes clínicos, achados radiológicos e resultados cirúrgicos, bem como as principais complicações. Resultados: A média de idade foi de 42,4 anos (variação de 19 a 70). Não houve predominância de gênero na taxa masculino versus feminino, 6:7. Os casos pontinos foram os mais frequentes. Ressonância nuclear magnética foi o método de imagem para o diagnóstico de cavernomas em todos os casos. A média do acompanhamento foi de 71,3 meses (variação de 1 a 138 meses). A apresentação clínica mais frequente foi a paresia do VIII nervo craniano, tinitus e perda auditiva (69,2%). Todos os 13 pacientes com cavernomas de tronco sintomáticos foram submetidos à ressecção cirúrgica. A remoção total foi realizada em 11 pacientes. A morbidade e a mortalidade foram de 15,3 e 7,6%, respectivamente. Conclusão: Os cavernomas podem ser seguramente ressecados por meio de acessos cirúrgicos ideais (zonas de entrada seguras) e técnicas de microcirurgia, sendo que o objetivo é remover toda a lesão sem o comprometimento dos nervos cranianos.

Central chemoreceptors and neural mechanisms of cardiorespiratory control

The arterial partial pressure (P CO2) of carbon dioxide is virtually constant because of the close match between the metabolic production of this gas and its excretion via breathing. Blood gas homeostasis does not rely solely on changes in lung ventilation, but also to a considerable extent on circulatory adjustments that regulate the transport of CO2 from its sites of production to the lungs. The neural mechanisms that coordinate circulatory and ventilatory changes to achieve blood gas homeostasis are the subject of this review. Emphasis will be placed on the control of sympathetic outflow by central chemoreceptors. High levels of CO2 exert an excitatory effect on sympathetic outflow that is mediated by specialized chemoreceptors such as the neurons located in the retrotrapezoid region. In addition, high CO2 causes an aversive awareness in conscious animals, activating wake-promoting pathways such as the noradrenergic neurons. These neuronal groups, which may also be directly activated by brain acidification, have projections that contribute to the CO2-induced rise in breathing and sympathetic outflow. However, since the level of activity of the retrotrapezoid nucleus is regulated by converging inputs from wake-promoting systems, behavior-specific inputs from higher centers and by chemical drive, the main focus of the present manuscript is to review the contribution of central chemoreceptors to the control of autonomic and respiratory mechanisms.

Further diffusion tensor imaging contribution in horizontal gaze palsy and progressive scoliosis / Contribuição adicional das imagens por tensores de difusão em paralisia do olhar conjugado horizontal associada a escoliose progressiva

In two siblings with clinical diagnosis of horizontal gaze palsy associated with progressive scoliosis (HGPPS) we could demonstrate by diffusion tensor imaging: (1) An anterior displacement of the transverse pontine fibers; (2) Posterior clumping of the corticospinal, medial lemniscus and central tegmental tracts and of the medial and dorsal longitudinal fasciculi complex; (3) Absent decussation of superior cerebellar peduncle. Those findings can contribute as surrogate markers for the diagnosis.

Em dois irmãos com diagnóstico clínico de paralisia do olhar conjugado horizontal associada a escoliose progressiva, foi possível determinar através de imagens por tensores de difusão: (1) Deslocamento anterior das fibras pontinas transversas; (2) Agrupamento posterior do trato córtico-espinhal, lemnisco medial e trato tegmentar central e complexos dos fascículos longitudinais medial e dorsal; (3) Ausência da decussação dos pedúnculos cerebelares superiores. Tais achados podem contribuir como marcadores para o diagnóstico.

Role of the serotoninergic system in the sodium appetite control

The present article reviews the role of the serotoninergic system in the regulation of the sodium appetite. Data from the peripheral and icv administration of serotoninergic (5-HTergic) agents showed the participation of 5-HT2/3 receptors in the modulation of sodium appetite. These observations were extended with the studies carried out after brain serotonin depletion, lesions of DRN and during blockade of 5-HT2A/2C receptors in lateral parabrachial nucleus (LPBN). Brain serotonin depletion and lesions of DRN increased the sodium appetite response, in basal conditions, after sodium depletion and hypovolemia or after beta-adrenergic stimulation as well. These observations raised the hypothesis that the suppression of ascending pathways from the DRN, possibly, 5-HTergic fibers, modifies the angiotensinergic or sodium sensing mechanisms of the subfornical organ involved in the control of the sodium appetite. 5-HTergic blockade in LPBN induced to similar results, particularly those regarded to the natriorexigenic response evoked by volume depletion or increase of the hypertonic saline ingestion induced by brain angiotensinergic stimulation. In conclusion, many evidences lead to acceptation of an integrated participation resulting of an interaction, between DRN and LPBN, for the sodium appetite control.

Este artigo revisa o papel do sistema serotoninérgico no controle do apetite ao sódio. Dados derivados da administração periférica e icv de agentes serotoninérgicos demonstraram a participação de receptores 5-HT2/3 na modulação do apetite ao sódio. Estas observações foram estendidas com os estudos realizados após a depleção cerebral de serotonina, lesões do NDR e durante o bloqueio 5-HT2A/2C no núcleo parabraquial lateral (NPBL). A depleção cerebral de serotonina e as lesões do NDR aumentaram o apetite ao sódio, em condições basais, após depleção de sódio, durante a hipovolemia ou após a estimulação beta-adrenérgica. Estas evidências suscitaram a hipótese de que a supressão de vias ascendentes do NDR, possivelmente 5-HT, alteram os mecanismos angiotensinérgicos e a atividade dos sensores de sódio do órgão subfornicial envolvidos no controle do apetite ao sódio. O bloqueio serotoninérgico no NPBL induziu a resultados similares, particularmente aqueles relacionados com a resposta natriorexigênica provocada pela depleção de volume ou o aumento da ingestão de salina hipertônica induzida pela estimulação angiotensinérgica cerebral. Em resumo, as evidências convergem para a admissão de uma participação integrada resultante da interação recíproca entre NDR e NPBL objetivando controlar o apetite ao sódio.

Hematoma traumático mesencéfalo-pontino em crianças de 7 anos e revisäo de literatura / Pontine-mesencephalic traumatic lesion in a seven-year-old child and revision of literature

Os hematomas mesencefálico-pontinos associados a traumatismo cranioencefálico (TCE) säo situaçöes bastante raras, e consideradas como fatais, de modo que a maioria dos casos descritos em literatura até entäo säo relatados post-mortem. A sua ocorrência está intimamente relacionada com a intensidade do TCE. Os autores relatam o caso de uma criança de 7 anos que sofreu um grave acidente de trânsito e teve um traumatismo crânio-encefálico com lesäo mesencéfalo-pontino com evoluçäo favorável. Os achados tomográficos iniciais foram dentre outros: múltiplas fraturas lineares temporais fechadas, pneumoencéfalo importante, hemorragia mesencéfalo -pontina com ectasia de terceiro ventrículo; e posteriormente uma área de encefalomalácia a nível de nesencéfalo e ponte. Revisando a literatura näo se encontra nenhum caso similar: TCE na faixa pediátrica com essas duas lesöes associadas

Angioma cavernoso do tronco encefálico - relato de caso / Cavernous angioma of the brainstem: case report

Angiomas cavernosos ocupam lugar de destaque dentre as manifestaçöes vasculares do sistema nervoso. Apresenta-se o caso de um paciente adulto com quadro neurológico iniciado subitamente (sindrome de tronco encefálico), após procedimento cirúrgico abdominal. Evoluiu favoravelmente com melhora espontânea, permanecendo com sequelas distúrbios da sensibilidade superficial da hemiface direita e membro inferior esquerdo e amiotrofia segmentar. Os exames de neuroimagem revelaram malformaçäo vascular (angioma cavernoso) do tronco encefálico (ponte). Os autores discutem a importância dos métodos de neuroimagem para determinaçäo diagnóstica e, principalmente, debatem aspectos da terapêutica conservadora e indicaçöes cirúrgicas

Pontine tegmentum hematoma: report of a case with pure hemiplegia

The authors report the case of a 50 years-old hypertensive male patient with a pontine hematoma. The clinical presentation was characterized by pure pyramidal deficit signs (no other sign or symptoms were present). A pure hemiplegia syndrome, although common in supratentorial lesions, is considered to be a rare event in pontine vascular lesions. The pathophysiologic mechanisms of these neurological findings are unclear. The exclusive involvement of the pyramidal tract in this case is likely due to a variation in the vascular anatomy of the pons but, in some cases, a vascular malformation may be the cause.

Acetylcholinesterase activity in the pons and medulla oblongata of rats after chronic electroconvulsive shock

An imbalance between cholinergic and noradrenergic neurotransmission has been proposed for the etiology of affective disorders. According to this hypothesis, depression would be the result of enhanced cholinergic and reduced noradrenergic neurotransmission. Repeated electroconvulsive shock (ECS) is an effective treatment for depression; moreover, in laboratory animals it induces changes in brain noradrenergic neurotransmission similar to those obtained by chronic treatment with antidepressant drugs (down-regulation of beta-adrenergic receptors). The aim of the present study was to determine whether repeated ECS in rats changes acetylcholinesterase (Achase) activity. Achase controls the level of acetylcholine (Ach) in the synaptic cleft and its levels seem to be regulated by the interaction between Ach and its receptor. Thus, a decrease in Achase activity would suggest decreased cholinergic activity. Adult male Wistar rats received one ECS (80 mA, 0.2s, 60Hz) daily for 7 days. Control rats were handled in the same way without receiving the shock. Rats were sacrificed 24 h after the last ECS and membrane-bound and soluble Achase activity was assayed in homogenates obtained from the pons and medulla oblongata. A statistically significant decrease in membrane-bound Achase activity (nmol thiocholine formed min-1 mg protein-1) (control 182.6 + 14.8 ECS 162.2 + 14.2, P<0.05) and an increase in soluble Achase activity in the medula oblongata (control 133.6 + 4.2, ECS 145.8 + 12.3, P<0.05) were observed. No statistical differences were observed in Achase activity in the pons. Although repeated ECS induced a decrease in membrane-bound Achase activity, the lack of changes in the pons (control Achase activity: total 231.0 + 34.5, membrane-bound 298.9 + 18.5, soluble 203.9 + 30.9), the region where the locus coeruleus, the main noradrenergic nucleus, is located, does not seem to favor the existence of an interaction between cholinergic and noradrenergic neurotransmission after ECS treatment.

Incontinência do choro e infarto protuberancial unilateral / Crying incontinence and unilateral pontine infarction

O presente estudo trata do caso de um paciente que apresentou incontinência do choro e hemiplegia direita por infarto ventroprotuberancial paramediano detectado pela RNM. O caráter circunscrito da lesäo foi endossado pela normalidade dos potenciais evocados sômato-sensitivos e auditivos de curta-latência. Os episódios de choro desapareceram poucos dias depois do início do tratamento com doses baixas de imipramina. Discutimos o choro e o riso patológicos como forma de incontinência da mímica resultante de desconexäo límbico-motora enfatizando a impropriedade de incluí-los na síndrome pseudobulbar, uma vez que dependem de correlatos anatômicos e funcionais distintos

Pontine tegmentum hematoma: a case report with the "one-and-a-half" syndrome without pyramidal tract deficit

O autor relata o caso de um paciente de sexo masculino de 54 anos com hematoma pontino que se manifestou por síndrome "one-and-a-half" e ataxia cerebelar mas sem sinais de acometimento do trato piramidal. A ausência de acometimento do trato piramidal é decorrente possivelmente de uma variaçäo da anatomia vascular do segmento pontino do tronco cerebral. Os achados clínicos do caso e os mecanismos fisiopatológicos da síndrome "one-and-a-half" säo discutidos

The development of human fetal pons. A quantitative study (9th to 12th weeks postconception)

The relative growth of pons weight was studied in 123 brazilian human fetuses of known age ranging from 9th to 12th weeks postconception using the allometric method. The pons weight was correlated to the fatal weight. The pons growth presented negative allometry during first gestational trimester. These data are imported to compare the fetal growth after ultrasound investigation