Clinical, tomographic, and postmortem aspects of a rare congenital Dicephalus Monauchenos Iniodymus in a Nelore calf produced in vitro from Brazil - case report

ABSTRACT The aim of this work was to report the occurrence of dicephalus iniodymus monauchenos in a Nellore newborn. A three-days old calf, from in vitro production, with duplication of the head and a history of cesarean birth was attended. On physical examination, the dicephalus, iniodymus and monauchenos, which were almost the same size and shape, had four eyes and four ears. Computed tomography showed the presence of two skulls fused with a common occipital foramen, two nasopharynxes, oropharynxes with the presence of a cleft lip and a cleft palate in the right head, which continued in a single esophagus and a single trachea. At necropsy, the presence of duplication of the cerebrum and cerebellum was observed, with union of the parts in the region of the trapezoid body of the brainstem and continued as a single spinal cord. This study characterizes the clinical, tomographic, and necropsy findings of a dicephalus Nelore neonate.

STUDY OF OCCURRENCE OF THE ANTERIOR TUBERCLE IN THE MARGIN OF THE OCCIPITAL FORAMEN IN BIHAR STATE REGION

Background: The presence of structures that pass along the anterior margin of the occipital foramen interposed between the basilar part of the occipital and the atlas may reduce the circumference of the foramen causing compression of the spinal cord and leading to signs and symptoms of neurological decits due to its asymmetry. The aim of this study was to determine the incidence of anterior tubercle at the occipital foramen margin. Out of 50 skulls, 2 (4%) skulls shows occurrence of the anterior tubercle in the margin the occipital foramen/foramen magnum with different antero-posterior and transverse measurement . Tubercle was found in the anterior margin of the occipital foramen in 2 (two) skull, The incidence of occipital tubercle, probably formed by the apical ligament exostosis of the dens, was 04 %. In 1st case the tubercle had a triangular shape, was situated at the midpoint of the anterior margin of the foramen, with its apex facing back toward the occipital foramen and measuring about 4mm in the antero-posterior direction and 3 mm in the transverse. In 2nd case a pyramidal projection was found at the anterior margin of foramen magnum, with the apex directed backwards towards the posterior margin of foramen magnum. The tubercle measured 3.5 mm antero-posteriorly and 2mm transversely. The knowledge of the presence of the occipital tubercle is of great clinical importance, as it may lead in many cases to compression of the neurovascular structures.

About ascending degenerations in the brainstem and descending in the spinal cord (after damage to the lateral part of the brain between the occipital foramen and atlant)

Among the new ways of coloring the nervous tissue, which gave us a lot of new facts and partly contributing to the changes in our previous information about the course of fibers in the central nervous system, is the Marchi method, which is very common at the present time, due to its extreme convenience and simplicity in defining degeneration nerve fibers.

Acts Aspect to the result of a cerebral hemorrhagic supratentorial session on the basics of analisys in the tentorial wedge

Cerebral transtentorial herniation determinates the course of progressive focal supratentorial impairments and acute hemorrhagic hemispheric stroke. Clinical and pathomorphological comparisons were done in patients with acute hemorrhagic hemispheric stroke. The following predictors of hemorrhagic hemispheric stroke lethal outcome were verified: 1) acute onset of coma in association with oculomotor dysfunctions; 2) focal hemiplegia in association with peduncular hemiplegia and paratonic rigiditydue due to compression of ipsilateral peduncle; 3) quick addition of vital disorders due to hemorrhagies into tectorium and it’s necrobiosis; 4) lethal outcome caused by herniation into occipital foramen due to necrobiosis of neurons in caudal part of brain stem tectorium.

Phylogenetic relationships and comparative larval morphology of epigean and stygobitic species of Limbodessus Guignot, 1939 (Coleoptera: Dytiscidae: Bidessini), with a key of identification

The larvae of five epigean and 25 stygobitic species of the diving beetle genus Limbodessus Guignot, 1939 are describedand illustrated for the first time, with special emphasis on morphometry and chaetotaxy of the cephalic capsule, headappendages, legs, last abdominal segment and urogomphi. Those of the following five epigean species are described: L.amabilis (Clark, 1862), L. compactus (Clark, 1862), L. inornatus (Sharp, 1882), L. praelargus (Lea, 1899), L. shuckardii(Clark, 1862). The 25 stygobitic larvae described are: L. barwidgeeensis Watts & Humphreys, 2006, L. bigbellensis(Watts & Humphreys, 2000), L. challaensis (Watts & Humphreys, 2001), L. cooperi Watts & Humphreys, 2006, L.eberhardi (Watts & Humphreys, 1999), L. exilis Watts & Humphreys, 2006, L. fridaywellensis (Watts & Humphreys,2001), L. hillviewensis (Watts & Humphreys, 2004), L. hinkleri (Watts & Humphreys, 2000), L. leysi Watts & Humphreys,2006, L. macrohinkleri Watts & Humphreys, 2006, L. masonensis (Watts & Humphreys, 2001), L. millbilliensis Watts &Humphreys, 2006, L. mirandaae Watts & Humphreys, 2006, L. morgani (Watts & Humphreys, 2000), L. nambiensisWatts & Humphreys, 2006, L. ordinarius Watts & Humphreys, 2009, L. palmulaoides Watts & Humphreys, 2006, L.pulpa (Watts & Humphreys, 1999), L. raeae Watts & Humphreys, 2006, L. raesideensis (Watts & Humphreys, 2001), L.windarraensis (Watts & Humphreys, 1999), L. yandalensis Watts & Humphreys, 2006, L. yarrabubbaensis Watts & Humphreys, 2009, L. yuinmeryensis (Watts & Humphreys, 2003). The morphology and chaetotaxy of epigean vs.stygobitic species are compared, and a key for the identification of the species is presented. Contrary to their epigeancounterparts, larvae of stygobitic Limbodessus have turned out to be very divergent morphologically. In addition to thecommon characteristics associated with an underground living (i.e., absence of stemmata, reduced pigmentation, and thinor soft exoskeleton), larvae of these species have undergone a variable modification of the frontoclypeus and have evolvedrelatively shorter tarsal claws. Two morphological groups of stygobitic species are evident, one including species lessdeviated from the ancestral (epigean) condition and another group comprising more modified species that typically havea larger size, a more or less pyriform head with a digitiform nasale, and a strongly reduced occipital foramen. Primarychaetotaxy of the species has remained a very conservative expression of the phenotype. Secondary chaetotaxy showsvariation among the species, the most obvious being the variable number of lamellae clypeales and the presence or absenceof secondary setae on the urogomphus. The phylogenetic relationships of Limbodessus are analyzed cladistically. Larvaeof this genus lack the primary pore ABc, which is a synapomorphy of the tribe Bidessini. As presently defined, Limbodessus is probably paraphyletic with respect to Allodessus Guignot, 1953.

Descriptions of the first-instar larva of the hypogaeic species Neobidessodes limestoneensis (Watts & Humphreys) and of the third-instar larva of Hydroglyphus balkei Hendrich (Coleoptera: Dytiscidae: Bidessini) with phylogenetic considerations

The first-instar larva of Neobidessodes Hendrich & Balke (through the hypogaeic species N. limestoneensis (Watts & Humphreys)) and the third-instar larva of Hydroglyphus Motschulsky (through H. balkei Hendrich) (Dytiscidae: Bidessini) are described and illustrated in detail for the first time, including detailed morphometric and chaetotaxic analyses of the cephalic capsule, head appendages, legs, last abdominal segment and urogomphi. A cladistic analysis including 51 characters and 32 hydroporine taxa is performed, which supports the inclusion of both genera in the tribe Bidessini based on the absence of the primary pore ABc on the last abdominal segment. The third instar of H. balkei is characterized by the absence of secondary setae on the urogomphi and anterior secondary setae on the coxa, and the presence of 8–9 secondary setae on the mesofemur. On the other hand, the first instar of N. limestoneensis bears 14 lamellae clypeales on the anteroventral margin of the nasale. This species has evolved several morphological characters that are probably associated with its hypogaeic existence, including a lightly sclerotized body, relatively longer cephalic capsule and mandibles, a strongly reduced occipital foramen, absence of stemmata, and short claws. However, primary chaetotaxy apparently has remained as a very conservative expression of the phenotype.

Ruolo della Neuroradiologia nella diagnostica della malformazione di Chiari di I tipo

Chiari's type I malformation is defined as the caudal displacement of the cerebellar tonsils into the occipital foramen, sometimes associated with displacement of the cerebellar vermis. Syringomyelia is present in 65% of patients with Chiari's type I malformation and in 25% of all cases of tonsillar ectopia detected by MR scan. In contrast, asymptomatic syringomyelia is sporadic. MR investigation of the whole spinal cord is indicated when Chiari's type I malformation is present. Although the incidence of symptomatic patients increases when the ectopia exceeds 5 mm, there are no statistically significant correlations between the size of cerebellar ectopia and the incidence of syringomyelia or the degree of other clinical manifestations such as headache, Ménière's syndrome and inferior cranial nerve impairment. Symptoms and hence prognosis and possible surgical treatment depend not only on the tonsillar displacement, but on its impact on CSF dynamics. Cine-MR scanning offers great potential in the assessment of CSF dynamics in the occipital foramen, revealing asymptomatic subjects at risk of developing syringomyelia. The surgical treatment of this category of patients remains a controversial topic.