A glass micropipette vacuum technique of cerebrospinal fluid sampling in C57BL/6 mice / 生理学报

The purpose of this study was to establish a suitable method for extracting cerebrospinal fluid (CSF) from C57BL/6 mice. A patch clamp electrode puller was used to draw a glass micropipette, and a brain stereotaxic device was used to fix the mouse's head at an angle of 135° from the body. Under a stereoscopic microscope, the skin and muscle tissue on the back of the mouse's head were separated, and the dura mater at the cerebellomedullary cistern was exposed. The glass micropipette (with an angle of 20° to 30° from the dura mater) was used to puncture at a point 1 mm inboard of Y-shaped dorsal vertebral artery for CSF sampling. After the first extraction, the glass micropipette was connected with a 1 mL sterile syringe to form a negative pressure device for the second extraction. The results showed that the successful rate of CSF extraction was 83.33% (30/36). Average CSF extraction amount was (7.16 ± 0.43) μL per mouse. In addition, C57BL/6 mice were given intranasally ferric ammonium citrate (FAC) to establish a model of brain iron accumulation, and the CSF extraction technique established in the present study was used for sampling. The results showed that iron content in the CSF from the normal saline control group was not detected, while the iron content in the CSF from FAC-treated group was (76.24 ± 38.53) μmol/L, and the difference was significant. These results suggest that glass micropipette vacuum technique of CSF sampling established in the present study has the advantages of simplicity, high success rate, large extraction volume, and low bleeding rate, and is suitable for the research on C57BL/6 mouse neurological disease models.

Safety assessment of multiple repeated percutaneous punctures for the collection of cerebrospinal fluid in rats

The objective of this study was to examine the safety of multiple repeated percutaneous punctures of cisterna magna for collecting cerebrospinal fluid (CSF) and preliminarily determine the optimal time interval and volume at each collection. Sixty Wistar rats were randomly assigned to six groups: 10 d-0 μL, 10 d-100 μL (100 μL CSF collected at an interval of 10 days), 10 d-150 μL, 15 d-0 μL, 15 d-100 μL, and 15 d-150 μL. CSF was collected by percutaneous puncture of the cisterna magna at four time-points. Simultaneously, locomotor activity, cisterna magna pressure, and acetylcholine levels in the CSF were monitored. Compared with the 10 d-0 μL group, the escape latency by Morris water maze was significantly prolonged in the 10 d-100 μL and 10 d-150 μL groups (P<0.05). Compared with the 15 d-0 μL group, the indices of 15 d-100 μL and 15 d-150 μL groups had no significant differences. When compared with that at the first training, the exception of the 10 d-150 μL and 15 d-150 μL groups, significant differences in escape latency were found at the 6th attempt (P<0.05). Compared with baseline readings for each group, the cisterna magna pressure in the 10 d-150 μL group began to decrease significantly from the third measurement (P<0.05). The optimal time interval during four CSF collections (100 μL per collection) via cisterna magna percutaneous puncture was determined to be 15 days. The procedure did not significantly affect learning processes, performance, or other related indices.

Pioneers in the cisterna magna puncture / Pioneiros na punção da cisterna magna

Abstract At the beginning of the 20th century, cerebrospinal fluid (CSF) collection and analysis emerged as a promising aid in the diagnosis of diseases of the central nervous system. It was obtained through the established procedure of lumbar puncture, described by Heinrich Quinke in 1891. The search for an alternative way to gather the CSF emerged in animal research, highlighting the cisterna magna as a promising source, with relative safety when performed by someone trained. Described initially and in detail by James Ayer in 1920, the procedure was widely adopted by neurologists and psychiatrists at the time, featuring its multiple advantages and clinical applications. After a period of great procedure use and exponential data collection, its complications and risks relegated the puncture of the cisterna magna as an alternative route that causes fear and fascination in modern Neurology.

Resumo No início do século XX, a coleta e análise do líquido cefalorraquidiano (LCR) despontavam como um promissor auxílio no diagnóstico das doenças do sistema nervoso central. Sua obtenção se dava através do consagrado procedimento de punção lombar, descrito por Heinrich Quinke em 1891. A busca por uma via alternativa na obtenção do LCR ganhou destaque nas pesquisas animais, destacando-se na cisterna magna promissora fonte, com relativa segurança quando executada por alguém treinado. Descrito inicialmente e de maneira pormenorizada por James Ayer em 1920, o procedimento foi amplamente adotado por neurologistas e psiquiatras à época, com destaque para suas múltiplas vantagens e aplicações clínicas. Após um período de grande uso do procedimento e exponencial obtenção de dados, suas complicações e riscos relegaram a punção da cisterna magna como via alternativa que causa medo e fascínio na Neurologia moderna.

Persistent Malfunction of Glymphatic and Meningeal Lymphatic Drainage in a Mouse Model of Subarachnoid Hemorrhage

Subarachnoid hemorrhage (SAH) is a devastating cerebrovascular event that often is followed by permanent brain impairments. It is necessary to explore the pathogenesis of secondary pathological damages in order to find effective interventions for improving the prognosis of SAH. Blockage of brain lymphatic drainage has been shown to worsen cerebral ischemia and edema after acute SAH. However, whether or not there is persistent dysfunction of cerebral lymphatic drainage following SAH remains unclear. In this study, autologous blood was injected into the cisterna magna of mice to establish SAH model. One week after surgery, SAH mice showed decreases in fluorescent tracer drainage to the deep cervical lymph nodes (dcLNs) and influx into the brain parenchyma after injection into the cisterna magna. Moreover, SAH impaired polarization of astrocyte aquaporin-4 (AQP4) that is a functional marker of glymphatic clearance and resulted in accumulations of Tau proteins as well as CD3⁺, CD4⁺, and CD8⁺ cells in the brain. In addition, pathological changes, including microvascular spasm, activation of glial cells, neuroinflammation, and neuronal apoptosis were observed in the hippocampus of SAH mice. Present results demonstrate persistent malfunction of glymphatic and meningeal lymphatic drainage and related neuropathological damages after SAH. Targeting improvement of brain lymphatic clearance potentially serves as a new strategy for the treatment of SAH.

In Vivo Spinal Distribution of Cy5.5 Fluorescent Dye after Injection via the Lateral Ventricle and Cisterna Magna in Rat Model

OBJECTIVE: The purpose of this study was to find an optimal delivery route for clinical trials of intrathecal cell therapy for spinal cord injury in preclinical stage.METHODS: We compared in vivo distribution of Cy5.5 fluorescent dye in the spinal cord region at various time points utilizing in vivo optical imaging techniques, which was injected into the lateral ventricle (LV) or cisterna magna (CM) of rats.RESULTS: Although CM locates nearer to the spinal cord than the LV, significantly higher signal of Cy5.5 was detected in the thoracic and lumbar spinal cord region at all time points tested when Cy5.5 was injected into the LV. In the LV injection Cy5.5 signal in the thoracic and lumbar spinal cord was observed within 12 hours after injection, which was maintained until 72 hours after injection. In contrast, Cy5.5 signal was concentrated at the injection site in the CM injection at all time points.CONCLUSION: These data suggested that the LV might be suitable for preclinical injection route of therapeutics targeting the spinal cord to test their treatment efficacy and biosafety for spinal cord diseases in small animal models.

In Vivo Spinal Distribution of Cy5.5 Fluorescent Dye after Injection via the Lateral Ventricle and Cisterna Magna in Rat Model

OBJECTIVE: The purpose of this study was to find an optimal delivery route for clinical trials of intrathecal cell therapy for spinal cord injury in preclinical stage. METHODS: We compared in vivo distribution of Cy5.5 fluorescent dye in the spinal cord region at various time points utilizing in vivo optical imaging techniques, which was injected into the lateral ventricle (LV) or cisterna magna (CM) of rats. RESULTS: Although CM locates nearer to the spinal cord than the LV, significantly higher signal of Cy5.5 was detected in the thoracic and lumbar spinal cord region at all time points tested when Cy5.5 was injected into the LV. In the LV injection Cy5.5 signal in the thoracic and lumbar spinal cord was observed within 12 hours after injection, which was maintained until 72 hours after injection. In contrast, Cy5.5 signal was concentrated at the injection site in the CM injection at all time points. CONCLUSION: These data suggested that the LV might be suitable for preclinical injection route of therapeutics targeting the spinal cord to test their treatment efficacy and biosafety for spinal cord diseases in small animal models.

Rat Cerebrospinal Fluid Treatment Method through Cisterna Cerebellomedullaris Injection / 神经科学通报·英文版

Drugs that lack the ability to cross the blood-brain barrier (BBB) need to be placed directly into the central nervous system. Our laboratory studies the involvement of the glutamatergic system in the aggressiveness of glioma, and some ligands of glutamate receptors cannot permeate the BBB. Here, glioma-implanted rats were treated by a technique that delivers ligands directly into the cerebrospinal fluid by puncture into the cisterna cerebellomedullaris. Rats were anesthetized and fixed in a rodent stereotactic device. The head was gently tilted downwards at an angle that allowed exposure of the cisterna. Injection into the cisterna was done freehand using a gingival needle coupled to a microsyringe. The efficiency of intracisternal injection was demonstrated using a methylene blue solution. This type of injection is adaptable for any rodent model using small volumes of a variety of other drugs, and is an interesting method for neuroscience studies.

A Case of Smith-Magenis Syndrome with Multiple Organ Malformations

Smith-Magenis syndrome (SMS) is a genetic disease caused by microdeletion of p11.2 in chromosome 17. SMS patients have characteristic facial features and accompanying congenital malformations involving the brain, cardiovascular system, and urinary tract. Compared with the distinctive facial characteristics, organ malformations are less common. Several cases of SMS with tetralogy of Fallot have been reported in Korea, none of which were accompanied by other organ malformations. We present the first case report in Korea of an SMS patient with malformations of the brain, heart, and urinary tract.

Atypical Neonatal Marfan Syndrome with p.Glu1073Lys Mutation of FBN1: the First Case in Korea

Neonatal Marfan syndrome (nMFS) is considered to be on the most severe end of the spectrum of type I fibrillinopathies. The common features of nMFS include ascending aortic dilatation, severe mitral and/or tricuspid valve insufficiency, ectopia lentis, arachnodactyly, joint contractures, crumpled ear, loose skin, and pulmonary emphysema.We describe a newborn male diagnosed with nMFS. He presented several atypical features, such as diaphragmatic eventration, severe hydronephrosis with hydroureter, and dilated cisterna magna. Molecular analysis revealed a missense mutation at nucleotide 3217 (c.3217G>A) in exon 26 of the fibrillin-1 (FBN1) gene, resulting in the substitution of a glutamate for a lysine at codon 1073 (E1073K) in the 12th calcium binding epidermal growth factor-like domain of the FBN1 protein. Here we report a rare case of Nmfs with several combined atypical features, such as diaphragmatic eventration, severe hydronephrosis with hydroureter, and dilated cisterna magna. Our report is the first atypical nMFS case with p.Glu1073Lys mutation of FBN1 in Korea and may help clinicians with the diagnosis and follow-up of atypical nMFS.

Quadrigeminal cisterna lipoma: report of two cases and literature review / Lipoma da cisterna quadrigeminal: relato de dois casos e revisão da literatura

Intracranial lipomas are congenital, benign and slow-growing tumors. The incidence were 0.1 to 0.5 percent of all primary brain tumors and are often diagnosed in incidental findings of neuroradiological investigation. Lipoma in quadrigeminal region occurs in 25 percent of intracranial lipomas and has been reported as lipomas in quadrigeminal cistern (perimesencephalic cistern), quadrigeminal plate, ambiens cistern or superior medullary velum. MRI is the most major exam. The treatment is conservative in most cases, surgical removal is hampered by their deep location and contiguous with adjacent neurovascular structures. The authors report two cases of lipoma in the quadrigeminal region, incidental findings and discuss the clinical findings, neuroimaging and treatment.

Lipomas intracranianos são tumores congênito, benigno e de crescimento lento. Sua incidência é de 0.1 a 0.5 por cento de todos os tumores cerebrais primários e são frequentemente diagnosticados em achados incidental de investigação neuroradiológica. Lipoma na região quadrigeminal ocorre em 25 por cento dos lipomas intracranianos e tem sido relatados como lipomas na cisterna quadrigeminal (cisterna perimesencefálica), placa quadrigeminal, cisterna ambiens ou véu medular superior. O exame de eleição é ressonância magnética. O tratamento é conservador na maioria dos casos, a remoção cirúrgica é dificultada pela sua localização profunda e da contiguidade com estruturas neurovasculares adjacentes. Os autores relatam dois casos de lipoma na região quadrigeminal achados incidentalmente e discutem os achados clínicos, imagem e tratamento.

Lesión como malformación de Chiari secundaria a quiste aracnoidal de la cisterna cuadrigémina / Chiari malformation-like lesion secondary to arachnoid cyst of the quadrigeminal cistern

Se presenta el caso de una mujer de 31 años de edad con cefalea y cervicalgia que se agravaba con la maniobra de Valsalva, presentando además mareos, encontrándose una malformación de Chiari secundario a un quiste aracnoideo cuadrigeminal. Después de efectuada la resonancia magnética diagnóstica, la paciente fue sometida a descompresión del agujero magno y extirpación del quiste cuadrigeminal, seguido por la resolución tanto de la malformación de Chiari y el quiste. Los síntomas desaparecieron después de la cirugía y han permanecido completamente resuelto hasta la actualidad. En pacientes adultos que presentan signos y síntomas de una malformación de Chiari debido a la compresión de la médula por las las amígdalas cerebelosas, la presencia de un quiste aracnoideo de cisterna cuadrigéminal es una rara patología asociada que puede ser tratada quirúrgicamente.

We report a rare case of a 31-year-old woman with headache and pain manifested by cervicalgia that worsened with the Valsalva maneuver and dizziness, who was found to have a Chiari malformation secondary to a posterior fossa arachnoid cyst. After magnetic resonance imagining (MRI), the patient was submitted to foramen magnum decompression and arachnoid cyst removal that were followed by resolution of both the Chiari malformation and the cyst. The symptoms disappeared after surgery and have remained completely resolved to the present day. In adult patients who present with signs and symptoms of Chiari malformation due to direct medulla compression by the tonsils, a quadrigeminal cistern arachnoid cyst is a rare associated pathology that can be treated surgically.

Surgical Outcome of Adult Idiopathic Chiari Malformation Type 1

OBJECTIVE: The pathophysiology of idiopathic Chiari malformation (CM) type 1 is disturbance of free cerebrospinal fluid (CSF) flow and restoration of normal CSF flow is the mainstay of treatment. Additional migration of the medulla oblongata in pediatric patients is referred to as CM type 1.5, but its significance in adult patients is unknown. This study is to compare surgical outcomes of adult idiopathic CM type 1.5 with that of type 1. METHODS: Thirty-eight consecutive adult patients (M : F=11 : 27; median, 33.5; range, 18–63) with syringomyelia due to idiopathic CM type 1 were reviewed. Migration of the medulla oblongata was noted in 13 patients. The modified McCormick scale (MMS) was used to evaluate functional status before and one year after surgery. All patients underwent foramen magnum decompression and duroplasty. Factors related to radiological success (≥50% decrease in the diameter of the syrinx) were investigated. The follow-up period was 72.7±55.6 months. RESULTS: Preoperative functional status were MMS I in 11 patients and MMS II in 14 of CM type 1 and MMS I in 8 and II in 5 of CM type 1.5. Of patients with MMS II, 5/14 patients in group A and 3/5 patients in group B showed improvement and there was no case of deterioration. Radiological success was achieved in 32 (84%) patients and restoration of the cisterna magna (p=0.01; OR, 46.5) was the only significant factor. CONCLUSION: Migration of the medulla oblongata did not make a difference in the surgical outcome when the cisterna magna was restored.

Anatomy and physiology of cisternostomy / 中华创伤杂志(英文版)

Cisternostomy is defined as opening the basal cisterns to atmospheric pressure. This technique helps to reduce the intracranial pressure in severe head trauma as well as other conditions when the so-called sudden "brain swelling" troubles the surgeon. We elaborated the surgical anatomy of this procedure as well as the proposed physiology of how cisternostomy works. This novel technique may change the current trends in neurosurgery.

Dandy Walker: reporte de un caso / Dandy Walker: case report

Introducción: la malformación de Dandy­Walker es una alteración congénita que compromete el cerebelo y el cuarto ventrículo. Esta condición se caracteriza por agenesia o hipoplasia del vermis cerebeloso, dilatación quística del cuarto ventrículo y alargamiento de la fosa posterior. Aproximadamente el 80% de los pacientes presenta hidrocefalia. La triada característica de la malformación de Dandy-Walker que consiste: agenesia parcial o completa del vermis, dilatación quística del cuarto ventrículo y alargamiento de la fosa posterior. El diagnóstico prenatal es preferible realizarlo luego de las 18 semanas, el postnatal se hace con ultrasonido transfontanelar, resonancia magnética y tomografía axial computarizada. El tratamiento de esta patología está basado en el manejo de la hidrocefalia. 1 Caso: a continuación presentamos un caso clínico de Dandy Walker de la Unidad de Medicina Materno Fetal del Hospital Carlos Andrade Marín de Quito.

Introduction: Dandy-Walker malformation is a rare congenital disease involving the cerebellum and the fourth ventricle. This condition is characterized by agenesia or hypoplasia of the cerebellar vermis, cystic dilatation of the fourth ventricle, and enlargement of the posterior fossa. Approximately 80% of patients have hydrocephalus. Dandy-Walker malformation was described by Dandy and Blackfan in 1914. The characteristic triad of Dandy-Walker malformation is consisting of complete or partial agenesis of the vermis, cystic dilatation of the fourth ventricle and an enlarged posterior fossa. The prenatal diagnosis of Dandy-Walker malformation is better after 18 weeks of gestation. After birth it is best diagnosed with the help of transfontanelar ultrasound, magnetic resonance imaging, and computerized axial tomography. The treatment for this condition is based in the management of hydrocephalus. 1 Case: below is a case report of Dandy Walker at the Maternal Fetal Medical Unit of the Carlos Andrade Marin Hospital in Quito.

Stereological and Morphometric Analysis of MRI Chiari Malformation Type-1

OBJECTIVE: In this study, we aimed to investigate the underlying ethiological factors in chiari malformation (CM) type-I (CMI) via performing volumetric and morphometric length-angle measurements. METHODS: A total of 66 individuals [33 patients (20-65 years) with CMI and 33 control subjects] were included in this study. In sagittal MR images, tonsillar herniation length and concurrent anomalies were evaluated. Supratentorial, infratentorial, and total intracranial volumes were measured using Cavalieri method. Various cranial distances and angles were used to evaluate the platybasia and posterior cranial fossa (PCF) development. RESULTS: Tonsillar herniation length was measured 9.09+/-3.39 mm below foramen magnum in CM group. Tonsillar herniation/concurrent syringomyelia, concavity/defect of clivus, herniation of bulbus and fourth ventricle, basilar invagination and craniovertebral junction abnormality rates were 30.3, 27, 18, 2, 3, and 3 percent, respectively. Absence of cisterna magna was encountered in 87.9% of the patients. Total, IT and ST volumes and distance between Chamberlain line and tip of dens axis, Klaus index, clivus length, distance between internal occipital protuberance and opisthion were significantly decreased in patient group. Also in patient group, it was found that Welcher basal angle/Boogard angle increased and tentorial slope angle decreased. CONCLUSION: Mean cranial volume and length-angle measurement values significantly decreased and there was a congenital abnormality association in nearly 81.5 percent of the CM cases. As a result, it was concluded that CM ethiology can be attributed to multifactorial causes. Moreover, congenital defects can also give rise to this condition.

An unusual de novo duplication 10p/deletion 10q syndrome: The first case in Korea

We herein report an analysis of a female baby with a de novo dup(10p)/del(10q) chromosomal aberration. A prenatal cytogenetic analysis was performed owing to abnormal ultrasound findings including a choroid plexus cyst, prominent cisterna magna, and a slightly medially displaced stomach. The fetal karyotype showed additional material attached to the terminal region of chromosome 10q. Parental karyotypes were both normal. At birth, the baby showed hypotonia, upslanting palpebral fissures, a nodular back mass, respiratory distress, neonatal jaundice and a suspicious polycystic kidney. We ascertained that the karyotype of the baby was 46,XX,der(10)(pter-->q26.3::p11.2-->pter) by cytogenetic and molecular cytogenetic analyses including high resolution GTG- and RBG-banding, fluorescence in situ hybridization, comparative genomic hybridization, and short tandem repeat marker analyses. While almost all reported cases of 10p duplication originated from one of the parents with a pericentric inversion, our case is extraordinarily rare as the de novo dup(10p)/del(10q) presumably originated from a rearrangement at the premeiotic stage of the parental germ cell or from parental germline mosaicism.

Estudio neuropsicológico pre y posquirúrgico en dos niños de 8 años de edad con tumor en fosa posterior / Neuropsychological study pre and post surgical in two children aged 8 years with posterior fossa tumor

Objetivo: Identificar y describir las diferencias neuropsicológicas antes y después de resecar el tumor en 2 pacientes de 8 años de edad con una neoplasia en la fosa posterior. Metodología: Se realizó evaluación neuropsicológica pre y posquirúrgica a 2 pacientes de 8 años de edad del Instituto Nacional de Pediatría, uno femenino con quiste aracnoideo en cisterna paravermiana y otro masculino con meduloblastoma en vermis y se compararon los datos obtenidos antes de extirpación de tumor y después de ella. Para la obtención del IQ se aplicó el WISC-IV y para las otras funciones, la Evaluación Neuropsicológica Infantil (ENI), para niños de 5 a 16 años, obteniéndose sus valores en percentiles que se igualaron con la clasificación cualitativa. Resultados: Los 2 pacientes presentaron deficiencias en el IQ, en Funciones Cognitivas, en las Habilidades de Rendimiento Académico, así como en sus Funciones Ejecutivas. A pesar de que no se aplicó quimioterapia ni radioterapia, tanto antes de la cirugía, como después de la extirpación del tumor, empeorando dichas funciones después de la extirpación. Conclusiones: Los tumores en Fosa Posterior originan diversas alteraciones neuropsicológicas similares a las observadas con lesiones en la corteza cerebral, dichas alteraciones se hacen más severas después de la extirpación del tumor; esta evolución puede presentar un dilema a la luz de la Bioética: ¿Se prolonga la vida a expensas de mayor deterioro neurocognitivo al quitar el tumor, o no se opera para evitar mayor deterioro en la calidad de vida y se reduce el tiempo de vida?.

Aim: Identify and describe the neuropsychological differences before and after surgery in 2 patients 8 years of age with a tumor in the posterior fossa. Methodology: Neuropsychological assessment was performed before and after surgery to 2 patients (8 years of age), one female with arachnoid cyst in paravermian cyst and another male with medulloblastoma in vermis and we compared the data obtained before removal of tumor and after. We use the following Neuropsychological Tests: WISC-IV was applied to assess IQ and Child Neuropsychological Assessment (ENI) was to evaluate cognitive functions. Results: The 2 patients had deficits in IQ, cognitive functions, the academic performance skills and his executive skills, even without chemotherapy or radiotherapy, both before surgery and after removal of the tumor. These functions worsened after surgery. Conclusions: Posterior fossa tumors originate many various neuropsychological similar to those observed in cerebral cortex, these changes are most evident after removal of the tumor, this evolution can present a dilemma in light of Bioethics: Is justified to prolong the life at expense of neurocognitive impairment, after removing a big tumor, or not to operate preventing further deterioration in the quality of life and reducing the lifetime?.

Survival of Patients with Trisomy 18 Based on the Treatment Policy at a Single Center in Korea

PURPOSE: Although discussion about active treatment of trisomy 18 is increasing, there are no previous articles regarding this subject in Korea. In order to provide objective data about the clinical characteristics and survival of patients with trisomy 18, based on the treatment policy, to medical teams and parents with trisomy 18, we reviewed the medical records of such patients at a single center in Korea. METHODS: This is a retrospective study of 22 patients diagnosed with trisomy 18 at the Samsung Medical Center between 1995 and 2013. We collected data about the clinical characteristics, including demographics, birth history, diagnosis method, and associated anomalies. We analyzed the survival in days, according to three broad categories of treatment policy: give-up, conservative management and active treatment. RESULTS: Of the 22 patients with confirmed trisomy 18, the majority were female (19, 86%). The median gestational age was 39 weeks (range, 31-41 weeks) and the median birth weight is 2,029 g (range, 1,130-2,990 g). Among the anomalies associated with trisomy 18, ventricular septal defect (86%) and patent ductus arteriosus (81%) were the most common cardiac anomalies; giant cisterna magna (59%) was the most common central nervous system anomaly; and clenched hands (73%) and low set ears (59%) were the most common structural anomalies. The survival based on the treatment policy was the highest in the active treatment group, followed by the conservative management group. The give-up group had the lowest survival. CONCLUSION: It is possible to achieve an improvement in both survival and symptom relief for patients with trisomy 18, despite poor neurological outcome and high mortality. Medical personnel need to provide objective data on trisomy 18 to the parents, and determine the treatment policy through careful discussion.

Ultrasound measurement of fetal posterior fossa at 11 to 13⁺⁶ gestational weeks for screening open spina bifida / 南方医科大学学报

<p><b>OBJECTIVE</b>To establish the normal reference ranges of transabdominal ultrasound measurements of the posterior fossa structure in fetuses at 11 to 13⁺⁶ gestational weeks and explore their clinical value in screening open spina bifida (OSB).</p><p><b>METHODS</b>Between January, 2013 and September, 541 randomly selected normal fetuses underwent nuchal translucency at the gestational age 11 to 13⁺⁶ weeks. The parameters of the posterior fossa were measured in mid-sagittal view of the fetal face and the axial view of the transverse cerebellum insonated through the anterior fontanel by transabdominal ultrasound to establish the normal reference ranges. The measurements were obtained from 3 fetuses with OSB for comparison with the reference ranges.</p><p><b>RESULTS</b>In normal fetuses, the parameters of the posterior fossa measured in the two views showed no significant differences (P>0.05). Two high echogenic lines were observed in normal fetuses, as compared with one in fetuses with OSB representing the posterior border of the brain stem and the anterior border of the fourth ventricle. The line between the posterior border of the fourth ventricle and the anterior border of the cisterna magna was not displayed in fetuses with OSB. The anteroposterior diameters of the brain stem, the fourth ventricle, and cisterna magna all increased in positive correlation with the crown-lump length in normal fetuses. In the 3 OSB fetuses, the anteroposterior diameter of the brain stem exceeded the 95th percentile and the anteroposterior diameter of fourth ventrical-cisterner magena was below the 5th percentile of the reference range for CRL; the brain stem to fourth ventrical-cisterner magena anteroposterior diameter ratio was increased to above 1.</p><p><b>CONCLUSION</b>The established normal reference ranges of the parameters of fetal posterior fossa may provide assistance in early OSB detection. The absence of the posterior border of the fourth ventricle and the anterior border of the cisterna magna and a brainstem to fourth ventrical-cisterner magena anteroposterior diameter ratio greater than 1 can be indicative of OSB at 11 to 13⁺⁶ gestational weeks.</p>

Uroguanylin induces electroencephalographic spikes in rats / Uroguanilina induz potenciais em espiga no eletroencefalograma de ratos

Uroguanylin (UGN) is an endogenous peptide that acts on membrane-bound guanylate cyclase receptors of intestinal and renal cells increasing cGMP production and regulating electrolyte and water epithelial transport. Recent research works demonstrate the expression of this peptide and its receptor in the central nervous system. The current work was undertaken in order to evaluate modifications of electroencephalographic spectra (EEG) in anesthetized Wistar rats, submitted to intracisternal infusion of uroguanylin (0.0125 nmoles/min or 0.04 nmoles/min). The current observations demonstrate that 0.0125 nmoles/min and 0.04 nmoles/min intracisternal infusion of UGN significantly enhances amplitude and frequency of sharp waves and evoked spikes (p = 0.03). No statistical significance was observed on absolute alpha and theta spectra amplitude. The present data suggest that UGN acts on bioelectrogenesis of cortical cells by inducing hypersynchronic firing of neurons. This effect is blocked by nedocromil, suggesting that UGN acts by increasing the activity of chloride channels.

A uroguanilina (UGN) é um peptídeo endógeno que age em receptores do tipo guanilato ciclase de membrana de células intestinais e renais aumentando a produção de GMPc e regulando o transporte epitelial de eletrólitos e água. Pesquisas recentes demonstraram a expressão deste peptídeo e de seus receptores no sistema nervosa central. O presente trabalho foi realizado com objetivo de avaliar possíveis mudanças no espectro do eletroencefalograma (EEG) de ratos Wistar anestesiados, submetidos à infusão intracisternal de uroguanilina (0.0125 nmoles/min or 0.04 nmoles/min). Os resultados apresentados no corrente trabalho demonstram que a infusão intracisternal de ambas as doses de UGN aumenta significativamente a amplitude e frequência das espículas (p = 0.03). Não foram encontradas diferenças estatísticas na amplitude absoluta dos espectros alfa ou teta. Os dados apresentados neste trabalho mostram que a UGN age na bioeletrogênese de células corticais induzindo disparo hipersincrônico de neurônios. Este efeito é bloqueado por nedocromil, sugerindo que UGN atua pelo aumento de atividade de canais de cloreto.