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Reinhard L. Friede - One of the best experts on this subject based on the ideXlab platform.
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uncommon syndromes of cerebellar vermis aplasia ii tecto cerebellar dysraphia with occipital encephalocele
Developmental Medicine & Child Neurology, 2008Co-Authors: Reinhard L. FriedeAbstract:SUMMARY Two new cases are reported of a rare syndrome of malformations consisting of occipital encephalocele, aplasia of the vermis and deformity of the tectum. Less consistent components are aplasia of mammillary bodies, fusion of thalami, anomalies of cerebral gyral patterns, bifid atlas or bifid occipital squame, elevation of torcular, and cervical hydromyelia. One of the present cases had survived to the age of eight years with a ventricular shunt. This syndrome, of which five cases are known, is thought to be a tandem malformation in which either an occipital dysraphia or an encephalocele induces aplasia of the vermis. A classification of aplasias of the cerebellar vermis is proposed. RESUME Syndromes inhabituels d'aplasie du vermis cerebelleux. II: Dysraphie de la valvule de Vieussens avec encephalocele occipital Les auteurs rapportent deux nouveaux cas d'un syndrome malformatif rare avec encephalocele occipital, aplasie du vermis et deformation de la valvule de Vieussens. L'un des cas presentes a survecu jusqu'a l'âge de huit ans avec un shunt ventriculaire. Les auteurs pensent que le syndrome, dont tres peu de cas ont ete decrits, est lie a une malformation en tandem, la dysraphie ou l'encephalocele occipital provoquant l'aplasie du vermis au cours de son developpement. Une classification des aplasies du vermis cerebelleux est proposee. ZUSAMMENFASSUNG Seltene Syndrome mit Aplasie des Vermis cerebellaris. II: Dysraphie des Tectum cerebellare mit occipitaler Encephalocele Zwei neue Falle eines seltenen Missbildungssyndroms mit occipitaler Encephalocele, Aplasie des Vermis cerebellaris und Deformierung des Tectums werden beschrieben. Einer der beiden Falle hatte bis zum achten Lebensjahr mit einem ventrikularen Shunt uberlebt. Das Syndrom, von dem bisher nur sehr wenige Falle beschrieben worden sind, wird als eine Missbildung angesehen, bei der eine occipitale Dysraphie oder Encephalocele eine Aplasie des Vermis in seiner Anlage hervorruft. Eine Klassifikation der Aplasien des Vermis cerebellaris wird vorgeschlagen. RESUMEN Sindromes poco corrientes de la aplasia del vermis cerebeloso. II: Disrafia tectocerebelosa con encefalocele occipital Se aportan dos nuevos casos de un sindrome raro con malformacion consistiendo en una encefalocele occipital, aplasia del vermis y deformidad del tectum. Uno de los casos ha sobrevivido hasta la edad de ocho anos con una derivacion ventricular. El sindrome, de los cuales muy pocos casos se han descrito, se piensa que se trata de una malformacion en tandem en la cual una disrafia occipital o encefalocele induce a una aplasia de vermis en su inicio. Se propone una clasificacion de las aplasias del vermis cerebeloso.
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uncommon syndromes of cerebellar vermis aplasia i joubert syndrome
Developmental Medicine & Child Neurology, 2008Co-Authors: Reinhard L. Friede, Euge OltshauseAbstract:SUMMARY Necropsy findings are reported for a case of Joubert syndrome (familiar aplasia of cerebellar vermis with episodic hyperpnea, abnormal eye-movements, ataxia and retardation). The findings consisted of an almost total aplasia of the cerebellar vermis; dysplasias and numerous heterotopias of cerebellar nuclei; an almost total absence of pyramidal decussation; and anomalies in the structure of the inferior olivary nuclei, the descending trigeminal tract, solitary fascicle and of the dorsal column nuclei. The lesion resembled the Dandy-Walker malformation or simple aplasia of the cerebellar vermis in some of its aspects, but there were numerous others to set it apart—at least tentatively—as a distinct nosologic entity. RESUME Syndromes inhabituels d'aplasie du vermis cerebelleux. I: syndrome de Joubert L'article rapporte des donnees d'autopsie sur un cas de syndrome de Joubert (aplasie familiale du vermis cerebelleux avec hyperpnee episodique, mouvements oculaires anormaux, ataxie et retard mental). Ces donnees comprennent une aplasie presque totale du vermis cerebelleux, des dysplasies et de nombreuses heterotopies des noyaux cerebelleux; une absence presque totale de decussation pyramidale et des anomalies dans la structure de l'olive inferieure, du faisceau trigeminal descendant, du faisceau solitaire et des noyaux de la colonne dorsale. La lesion ressemblait a la malformation de Dandy-Walker ou aplasie simple du vermis cerebelleux par certains aspects mais elle s'en ecartait par de nombreux autres, permettant au moins a titre d'essai de definir une entite nosologique distincte. ZUSAMMENFASSUNG Seltene Syndrome mit Aplasie des Vermis cerebellaris. I: Joubert Syndrom Ein fall mit Joubert Syndrom (familiare Aplasie des Vermis cerebellaris mit episodischer Hyperpnoe, abnormen Augenbewegungen, Ataxie und Retardierung) wird im Autopsiebefund beschrieben. Die Befunde bestanden in fast totaler Aplasie des Vermis cerebellaris, Dysplasien und zahlreichen Heterotopien von cerebellaren Kernen, in fast totalem Fehlen der Pyramidenbahnkreuzung und Anomalien in der Struktur des Nucleus olivaris inferior, im absteigenden Trigeminusast, im Solitarfaszikel und in den Kernen des Hinterstranges. Die Lasion ahnelte der Dandy-Walker Missbildung oder der einfachen Aplasie des Vermis cerebellaris in einigen Punkten, jedoch sprachen zahlreiche weitere Aspekte dafur, das Joubert Syndrom als eine besondere nosologische Einheit von diesen zumindestens versuchsweise abzugrenzen. RESUMEN Sindromes infrecuentes de aplasia del vermis cerebeloso. I: Sindrome de Joubert Se aportan los hallozgos en la necropsia de un caso de sindrome de Joubert (aplasia fascicular del vermis cerebeloso por hiperpnea episodica, movimientos anomalos del ojo, ataxia y retraso). Los hallazgos consistian en una aplasia casi total del vermis cerebeloso; displasias y heterotopias numerosas de los nucleos cerebelosos; y ausencia casi total de la decusacion de las piramides; y anomalias en la estructura de los nucleos olivares inferiores, el tractotrigeminal descendente y el fasciculo solitario y de los nucleos de la columna dorsal. La lesion parecia una malformacion de Dandy-Walker o una aplasia simple del vermis cerebeloso en algunos de sus aspectos, pero habia otros numerosos aspectos que lo colocaban aparte (por lo menos de momento) como una entidad nosologica distinta.
H E Wichmann - One of the best experts on this subject based on the ideXlab platform.
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pets and Vermin are associated with high endotoxin levels in house dust
Clinical & Experimental Allergy, 2001Co-Authors: Joachim Heinrich, Ulrike Gehring, Jeroen Douwes, A Koch, B Fahlbusch, Wolfgang Bischof, H E WichmannAbstract:Background Previous studies have shown that the risk for allergic sensitization is lower in children who grew up on farms and in young adults who were exposed to dogs in early childhood. A higher microbial exposure in general and in particular to endotoxin in early childhood might contribute to this lower risk of atopy. Objective We examined whether the presence of pets or Vermin in the home is associated with higher endotoxin concentrations in settled house dust. Methods House dust was sampled in a standardized manner on the living room floors of 454 homes of German children aged 5–10 years (participation rate 61%). Endotoxin was assessed with a quantitative kinetic chromogenic Limulus Amebocyte Lysate (LAL) method. Associations between endotoxin levels, pets and Vermin are presented as ratios of the crude and confounder adjusted geometric means (means ratios) in the category of study vs. a reference category using multiple linear regression models. Results Endotoxin concentrations in living room floor dust sampled in homes without pets and Vermin were lower (1246 ng per square meter, 1519 ng endotoxin/g dust, n = 157) than those sampled in homes with pets or Vermin (2267 ng per square meter, 2200 ng endotoxin/g dust, n = 296). After adjustment for city of residence, season of dust sampling, age of the building and story of the dwelling, means ratios for endotoxin expressed per gram of dust were statistically significantly increased for dog (1.64, 95% CI 1.09–2.46), for cat (1.50, 95% CI 1.03–2.18) and for cockroach (3.01, 95% CI 1.37–6.60), whereas no major statistically significant associations were found for other pets, ants and mice. Conclusion Keeping a dog or a cat in the home is consistent with higher exposure to endotoxin and might therefore contribute to the lower risk of atopy in later life.
Euge Oltshause - One of the best experts on this subject based on the ideXlab platform.
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uncommon syndromes of cerebellar vermis aplasia i joubert syndrome
Developmental Medicine & Child Neurology, 2008Co-Authors: Reinhard L. Friede, Euge OltshauseAbstract:SUMMARY Necropsy findings are reported for a case of Joubert syndrome (familiar aplasia of cerebellar vermis with episodic hyperpnea, abnormal eye-movements, ataxia and retardation). The findings consisted of an almost total aplasia of the cerebellar vermis; dysplasias and numerous heterotopias of cerebellar nuclei; an almost total absence of pyramidal decussation; and anomalies in the structure of the inferior olivary nuclei, the descending trigeminal tract, solitary fascicle and of the dorsal column nuclei. The lesion resembled the Dandy-Walker malformation or simple aplasia of the cerebellar vermis in some of its aspects, but there were numerous others to set it apart—at least tentatively—as a distinct nosologic entity. RESUME Syndromes inhabituels d'aplasie du vermis cerebelleux. I: syndrome de Joubert L'article rapporte des donnees d'autopsie sur un cas de syndrome de Joubert (aplasie familiale du vermis cerebelleux avec hyperpnee episodique, mouvements oculaires anormaux, ataxie et retard mental). Ces donnees comprennent une aplasie presque totale du vermis cerebelleux, des dysplasies et de nombreuses heterotopies des noyaux cerebelleux; une absence presque totale de decussation pyramidale et des anomalies dans la structure de l'olive inferieure, du faisceau trigeminal descendant, du faisceau solitaire et des noyaux de la colonne dorsale. La lesion ressemblait a la malformation de Dandy-Walker ou aplasie simple du vermis cerebelleux par certains aspects mais elle s'en ecartait par de nombreux autres, permettant au moins a titre d'essai de definir une entite nosologique distincte. ZUSAMMENFASSUNG Seltene Syndrome mit Aplasie des Vermis cerebellaris. I: Joubert Syndrom Ein fall mit Joubert Syndrom (familiare Aplasie des Vermis cerebellaris mit episodischer Hyperpnoe, abnormen Augenbewegungen, Ataxie und Retardierung) wird im Autopsiebefund beschrieben. Die Befunde bestanden in fast totaler Aplasie des Vermis cerebellaris, Dysplasien und zahlreichen Heterotopien von cerebellaren Kernen, in fast totalem Fehlen der Pyramidenbahnkreuzung und Anomalien in der Struktur des Nucleus olivaris inferior, im absteigenden Trigeminusast, im Solitarfaszikel und in den Kernen des Hinterstranges. Die Lasion ahnelte der Dandy-Walker Missbildung oder der einfachen Aplasie des Vermis cerebellaris in einigen Punkten, jedoch sprachen zahlreiche weitere Aspekte dafur, das Joubert Syndrom als eine besondere nosologische Einheit von diesen zumindestens versuchsweise abzugrenzen. RESUMEN Sindromes infrecuentes de aplasia del vermis cerebeloso. I: Sindrome de Joubert Se aportan los hallozgos en la necropsia de un caso de sindrome de Joubert (aplasia fascicular del vermis cerebeloso por hiperpnea episodica, movimientos anomalos del ojo, ataxia y retraso). Los hallazgos consistian en una aplasia casi total del vermis cerebeloso; displasias y heterotopias numerosas de los nucleos cerebelosos; y ausencia casi total de la decusacion de las piramides; y anomalias en la estructura de los nucleos olivares inferiores, el tractotrigeminal descendente y el fasciculo solitario y de los nucleos de la columna dorsal. La lesion parecia una malformacion de Dandy-Walker o una aplasia simple del vermis cerebeloso en algunos de sus aspectos, pero habia otros numerosos aspectos que lo colocaban aparte (por lo menos de momento) como una entidad nosologica distinta.
Laura Petrosini - One of the best experts on this subject based on the ideXlab platform.
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lesion induced and activity dependent structural plasticity of purkinje cell dendritic spines in cerebellar vermis and hemisphere
Brain Structure & Function, 2016Co-Authors: Francesca Gelfo, Laura Petrosini, F Florenzano, Lorena Burello, Francesca Foti, P De BartoloAbstract:Neuroplasticity allows the brain to encode experience and learn behaviors, and also to re-acquire lost functions after damage. The cerebellum is a suitable structure to address this topic because of its strong involvement in learning processes and compensation of lesion-induced deficits. This study was aimed to characterize the effects of a hemicerebellectomy (HCb) combined or not with the exposition to environmental enrichment (EE) on dendritic spine density and size in Purkinje cell proximal and distal compartments of cerebellar vermian and hemispherical regions. Male Wistar rats were housed in enriched or standard environments from the 21st post-natal day (pnd) onwards. At the 75th pnd, rats were submitted to HCb or sham lesion. Neurological symptoms and spatial performance in the Morris water maze were evaluated. At the end of testing, morphological analyses assessed dendritic spine density, area, length, and head diameter on vermian and hemispherical Purkinje cells. All hemicerebellectomized (HCbed) rats showed motor compensation, but standard-reared HCbed animals exhibited cognitive impairment that was almost completely compensated in enriched HCbed rats. The standard-reared HCbed rats showed decreased density with augmented size of Purkinje cell spines in the vermis, and augmented both density and size in the hemisphere. Enriched HCbed rats almost completely maintained the spine density and size induced by EE. Both lesion-induced and activity-dependent cerebellar plastic changes may be interpreted as “beneficial” brain reactions, aimed to support behavioral performance rescuing.
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activity dependent structural plasticity of purkinje cell spines in cerebellar vermis and hemisphere
Brain Structure & Function, 2015Co-Authors: P De Bartolo, F Florenzano, Lorena Burello, Francesca Gelfo, Laura PetrosiniAbstract:The environmental enrichment (EE) paradigm is widely used to study experience-dependent brain plasticity. In spite of a long history of research, the EE influence on neuronal morphology has not yet been described in relation to the different regions of the cerebellum. Thus, aim of the present study was to characterize the EE effects on density and size of dendritic spines of Purkinje cell proximal and distal compartments in cerebellar vermian and hemispherical regions. Male Wistar rats were housed in an enriched or standard environment for 3.5 months from the 21st post-natal day onwards. The morphological features of Purkinje cell spines were visualized on calbindin immunofluorescence-stained cerebellar vermian and hemispherical sections. Density, area, length and head diameter of spines were manually (ImageJ) or automatically (Imaris) quantified. Results demonstrated that the Purkinje cell spine density was higher in enriched rats than in controls on both proximal and distal dendrite compartments in the hemisphere, while it increased only on distal compartment in the vermis. As for spine size, a significant increase of area, length and head diameter was found in the distal dendrites in both vermis and hemisphere. Thus, the exposure to a complex environment enhances synapse formation and plasticity either in the vermis involved in balance and locomotion and in the hemisphere involved in complex motor adaptations and acquisition of new motor strategies. These data highlight the importance of cerebellar activity-dependent structural plasticity underling the EE-related high-level performances.
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Cerebellar vermis abnormalities and cognitive functions in individuals with Williams syndrome
Research in developmental disabilities, 2013Co-Authors: Deny Menghini, Margherita Di Paola, Riccardo Murri, Floriana Costanzo, Carlo Caltagirone, Stefano Vicari, Laura PetrosiniAbstract:In Williams syndrome (WS) cerebellar measures were only indirectly related to behavioral outcomes. T1-weighted magnetic resonance images and neuropsychological data were acquired to investigate whether cerebellar vermis differences were present in 12 WS individuals compared with 13 chronological age-matched controls and whether WS cerebellar vermis measures were related to cognitive scores. In WS participants, we observed a significant increase in the volume of the posterior superior cerebellar vermis (lobules VI–VII) and an atypical ratio between width and height of the cerebellar vermis. Furthermore, we found an inverse correlation between cerebellar posterior vermis volume and scores on implicit learning, phonological fluency and the verbal short-term memory tasks. The present study supported a role for the posterior cerebellar vermis in higher cognitive processes and indicated that the cerebellar vermis abnormalities (enlargement) in WS individuals have an effect in worsening the cognitive performance in specific domains.
Andrea Rossi - One of the best experts on this subject based on the ideXlab platform.
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delayed rotation of the cerebellar vermis a pitfall in early second trimester fetal magnetic resonance imaging
Ultrasound in Obstetrics & Gynecology, 2016Co-Authors: Joana Pinto, Dario Paladini, Mariasavina Severino, Giovanni Morana, Rui Pedro Pais, Carola Martinetti, Andrea Rossi, Mariasavina Severino, Andrea RossiAbstract:We describe two cases in which delayed rotation of the cerebellar vermis simulated a Dandy-Walker malformation (DWM) on early second-trimester magnetic resonance imaging (MRI). Two pregnant women with suspected fetal posterior fossa anomaly on ultrasound examination underwent fetal MRI at 21 (Case 1) and 19 (Case 2) weeks' gestation. In both cases, upward rotation of the cerebellar vermis was noted; on midsagittal imaging, the brainstem-vermis angle was 28° and 43°, respectively, while cerebellar morphometry showed a reduced vermian anteroposterior diameter compared to reference data. The posterior fossa appeared to be mildly enlarged, while all other findings were normal. Follow-up MRI at 28 + 3 weeks' gestation (Case 1) and at 1 postnatal year (Case 2) showed completely normal findings. Both children had normal psychomotor development and neurological examinations at 1 year of age. Incomplete rotation of the cerebellar vermis can be a physiological finding on early second-trimester fetal MRI examination and can simulate DWM or other forms of cerebellar hypoplasia. Embryologically, delayed permeabilization of Blake's pouch could account for the delayed vermian rotation. Follow-up imaging at a later gestational age is crucial to ensure that this condition is not over-reported and to avoid the potential risk of unnecessary pregnancy interruption. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.
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Delayed rotation of the cerebellar vermis: an important pitfall in early second trimester fetal MR imaging studies
Ultrasound in obstetrics & gynecology : the official journal of the International Society of Ultrasound in Obstetrics and Gynecology, 2016Co-Authors: Joana Pinto, Dario Paladini, Mariasavina Severino, Giovanni Morana, Rui Pedro Pais, Carola Martinetti, Andrea Rossi, Mariasavina Severino, Andrea RossiAbstract:We describe two cases in which delayed rotation of the cerebellar vermis simulated a Dandy-Walker malformation (DWM) on early second-trimester magnetic resonance imaging (MRI). Two pregnant women with suspected fetal posterior fossa anomaly on ultrasound examination underwent fetal MRI at 21 (Case 1) and 19 (Case 2) weeks' gestation. In both cases, upward rotation of the cerebellar vermis was noted; on midsagittal imaging, the brainstem-vermis angle was 28° and 43°, respectively, while cerebellar morphometry showed a reduced vermian anteroposterior diameter compared to reference data. The posterior fossa appeared to be mildly enlarged, while all other findings were normal. Follow-up MRI at 28 + 3 weeks' gestation (Case 1) and at 1 postnatal year (Case 2) showed completely normal findings. Both children had normal psychomotor development and neurological examinations at 1 year of age. Incomplete rotation of the cerebellar vermis can be a physiological finding on early second-trimester fetal MRI examination and can simulate DWM or other forms of cerebellar hypoplasia. Embryologically, delayed permeabilization of Blake's pouch could account for the delayed vermian rotation. Follow-up imaging at a later gestational age is crucial to ensure that this condition is not over-reported and to avoid the potential risk of unnecessary pregnancy interruption. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.
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Expanding the spectrum of congenital anomalies of the diencephalic–mesencephalic junction
Neuroradiology, 2016Co-Authors: Mariasavina Severino, Domenico Tortora, Angela Pistorio, Luca Antonio Ramenghi, Flavia Napoli, Maria Margherita Mancardi, Pasquale Striano, Valeria Capra, Andrea RossiAbstract:Introduction We aimed to describe the clinico-radiological findings of patients with disorders of diencephalic–mesencephalic junction (DMJ) formation and midbrain anteroposterior patterning. Methods We reviewed the DMJ anatomy of 445 patients with brain malformations. Associated supra/infratentorial abnormalities and clinical findings were noted. Craniocaudal and anteroposterior diameters of midbrain, pons, medulla, vermis, and transverse cerebellar diameter were compared with age-matched controls. Post hoc tests were corrected according to Bonferroni ( p _B). Results Two patterns of DMJ anomaly were identified in 12 patients (7 females, mean age 41 months). Type A was characterized by hypothalamic–mesencephalic fusion on axial plane, with possible midbrain ventral cleft (7 patients). Anteroposterior ( p _B = .006) and craniocaudal ( p _B = .027) diameters of the pons, craniocaudal diameter of the vermis ( p _B = .015), and transverse cerebellar diameter ( p _B = .011) were smaller than the controls. Corticospinal tract, basal ganglia, and commissural anomalies were also associated. Clinical findings included spastic-dystonic tetraparesis, hypothalamic dysfunction, epilepsy, and severe developmental delay. Type B was characterized by incomplete thalamic–mesencephalic cleavage on sagittal plane, with parenchymal bands connecting the interthalamic adhesion with the midbrain (five patients). Anteroposterior diameters of midbrain ( p _B = .002), pons ( p _B = .0004), and medulla ( p _B = .002) as well as the vermian anteroposterior ( p _B = .040) and craniocaudal diameters ( p _B = .014) were smaller than the controls. These patients were less neurologically impaired, most presenting mild developmental delay. Conclusions The spectrum of DMJ patterning defects is wide and may be associated with several brain malformations. Infratentorial brain structures should be carefully evaluated to better define the type of associated midbrain–hindbrain anomalies.
