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V Meininger

Publications and source records attributed to V Meininger.

At least 73 records · Page 4Linked to original sources

[Organization of pectoral muscle motor neurons in the rat. Contribution to the study of the axillary arch (Achselbogen)].

In spite of their role of the forelimb activity, the organization of the mammalian pectoral muscles remains unclear. In order to get more information, we have studied, qualitatively and quantitatively, the motor pools of the various pectoral muscles in the rat (musculus pectoralis major, musculus pectoralis minor and musculus panniculus carnosus). The method applied was the retrograde transport of horseradish peroxidase by the peripheral nerves supplying the various muscles. The results provided the precise localization within the ventral horn of the motor neurons from the pectoral muscles which were all in the most ventral part of the gray matter. Three distinct motor pools were observed, which confirms the functional identity of each muscle. The motor neurons of m. panniculus carnosus exhibited some particularities. They were 4 times more numerous than those from m. pectoralis major, they occupied the whole ventral edge of the ventral horn, from its medial part to its lateral tip. The cell size was different from that of the other muscles. These results were discussed, according to the role of this muscle, which links the forelimb to the whole trunk. In mammals, m. panniculus carnosus constitutes, with musculus latissimus dorsi, the axillary arch (Achselbogen). A small area of overlapping between the motor pools of these two muscles was observed. It was suggested that the muscular fibers from the axillary arch were innervated by the same, well-defined spinal area, independent of the muscle from which they originate.

Animals

[Neuropathological study of adult intracranial hemorrhage. III. Analysis of 107 meningeal hemorrhages due to rupture of arterial aneurysms].

The findings in 107 pathological studies of meningeal hemorrhages due to rupture of arterial saccular aneurysms are reported. There were 62 women (58 p. 100) and 45 men (42 p. 100). Mean age was 56, lower in men (53) than in women (58). 45 aneurysms of the Anterior Communicating Artery, 26 of the Middle Cerebral Artery, 15 of the Internal Carotid Artery, 10 of the Anterior Cerebral Artery, 1 of the Anterior Choroidal Artery and 10 of the Posterior System were studied. These ruptured aneurysms were compared to 31 non ruptured ones. Mean size of the ruptured aneurysms was 10, 62 mm, not statistically different from that of non ruptured aneurysms (9, 05 mm). Multiple aneurysms represent 10 p. 100 of the whole ruptured aneurysms population. They affected mostly the Middle Cerebral Artery. High blood pressure had been present in 56/107 cases of ruptured aneurysms (52 p. 100). The prevalence of high blood pressure in patients with ruptured aneurysms (men: 60 p. 100 between 35 and 49, 63 p. 100 between 50 and 64; women: 31 p. 100 between 35 and 49, 54 p. 100 between 50 and 64) was statistically higher than in the same age and sex ranges of the general French population. The other causes of bleeding were rare: 4 liver cirrhosis (2 of the patients were also hypertensive) and 5 anticoagulant therapies (2 of which were also associated with high blood pressure). Intracerebral hematomas were found in 43 cases (40 p. 100): 39 lobar, more frequent in the frontal (26) than in the temporal (13) lobes, due mainly to Anterior Communicating Artery and Anterior Cerebral Artery aneurysms; very few were in the basal ganglia (3) or brainstem (I). Intraventricular hemorrhage was found in 39 cases (36 p. 100). Forty (37 p. 100) cerebral infarcts had occurred. They were located in the territory of the same artery in 20 cases (19 p. 100), in a different territory in 11 cases (10 p. 100), in both in 9 cases (8. p. 100).

Adult

[Neuropathological study of adult intracranial hemorrhage. General data in 500 cases].

The systematic pathological study of 500 patients with intracranial hemorrhages (ICH) [341 (68 P. 100) CEREBRAL HEMORRHAGES (C.H.); 119 (24 p. 100) meningeal hemorrhages (M.H.); 39 (7,8 p. 100) subdural hematomas (S.H.) and, at last, one extradural hematoma] has been practiced. Those cases were issued primarily from neurological and, at a lesser degree, from neurosurgical departments. Etiological data, complications, associated findings and causes of death have been analysed. High blood pressure is the main etiological factor in C.H. This is confirmed by the statistical comparison between the incidence of this factor in our material and in the whole French population. However, nearly 50 p. 100 of ICH occuring in normotensive patients are C.H. The incidence of cirrhosis is much higher in our study than in other reports from the literature. The frequently associated high blood pressure does not seem to enhance the incidence of CH in patients with liver cirrhosis. Although this last factor can be found alone, its real etiological importance in CH cannot be assessed on account of the lack of data concerning the incidence of liver cirrhosis in the French population. The incidence of anticoagulant therapy is high in S.H. On the contrary, this factor does not seem to enhance the risk of high blood pressure induced C.H. The traumatic etiology of S.H. is significantly higher than the anticoagulant therapy etiology which, however, is very high in our study.

Adult

[Contribution to anatomical and clinical studies of avoidance phenomena (author's transl)].

The authors report 5 cases of avoiding phenomenon of the hand from parietal lesions. Four of these patients were operated for intractable epilepsy, from a parietal cortectomy that implicated a certain amount of white matter. The avoiding phenomena observed are analyzed as elementary motor perturbations rather than a disturbance of motor comportment. The authors distinguish two types of avoiding phenomena: 1--Avoiding phenomenon of dystonic type occurs during any motor activity and persists during all its development. It is probably related to the removal of the cortex of the post-central gyrus and of the anterior part of the superior parietal lobule; 2--The initial avoiding phenomenon is brief and occurs only at the beginning of the movements which implicate solely the upper limb; it seems related to the removal of the internal part of the superior parietal lobule that corresponds approximately to areas 5 and 7 from Brodmann. Some hypotheses are discussed concerning the possible physio-pathological mechanisms of these disturbances.

Adolescent

[Motoneural organisation of the anterior horn with respect to the peripheral nerves in the rat (as studied by the method of retrograde transport of horseradish peroxidase)(author's transl)].

The motoneuronal organisation of the anterior horn with respect to the peripheral nerves, is still imprecise due to methodological problems. The chromatolytic and Golgi methods have furnished some fruitful but incomplete data. The retrograde transport of horseradish peroxidase permits to obtain both the topography of cells and their dendritic tree. With such a method we studied the cervical enlargment of the rat's spinal cord. Each nerve is in relation with a column of motoneurons whose both the metameric extension and the exact topography in the anterior horn have been defined. An histogram of the cell volumes has been performed for some nerves. These data permit to discuss the possible significance of the topographical separation of the cells related to the girdle with those in relation with the distal part of the upper limb. The histogram shows that the small cells, claimed to be gamma motoneurons, are much more numerous than generally supposed. The significance of the dendritic tree, which seemed oriented selectively in the cranio-caudal axis, is discussed.

Animals

[Dendroarchitectonic study of the neurons of the corpus quadrigeminum superius in man].

Two different functional zones may be described in the superior colliculus. The superficial layers receive retinal and cortical fibers, the deep layers are a multimodal center and are implied in the oculo-motor control mechanisms. The aim of the present study has been to use network analysis in order to quantify the cell types of the deep layers of the superior colliculus in Man. 50 Golgi impregnated cell have been drawn in the three plans of space. Topological analysis permits to emphasize the existence of two different cell types: collaterally-branched cells or CB cells, and dichotomously-branched cells or DR cells. Quantitative analysis of the dendritic arcs has shown the spatial orientation of the dendritic tree. The proximal dendrites of DR cells are in the horizontal plane, the terminal dendrites are in the vertico-frontal plane. This difference seems to be due to different functional afferences.

Aged

[Intramedullary topography of the motor neurons of the brachial plexus of the rat. Preliminary study].

The exact localisation of the motor pools of anterior horn providing the different nerves of the brachial plexus remains unclear. The data obtained have been furnished by different methods: Nissl methods furnish cytoarchitectonic data -- Golgi methods furnish dendro-architectonic data. The topographical data were obtained by the chromatolytic modifications of the moto-neurons after a peripheral nerve injury. The recently used method of the retrograde transport of HRP permits to get information about the exact localisation and the dendritic extent of the neurons of a motor pool related to a particular nerve. We have studied the localisation of the nerves of the brachial plexus in the cervical enlargement of the spinal cord. We have determined the exact extent of the different motor pools in relation to each nerve. It seems that two different regions may be recognized in the anterior horn: a ventro lateral one in relation with the girdle muscles and a dorso lateral region related with the more distal muscles of the anterior limb.

Animals

Bilateral tactile aphasia: a tacto-verbal dysfunction.

Bilateral tactile aphasia was exhibited by a patient who was operated upon for a left parieto-occipital haematoma. Neuropsychological investigation established the following points: (1) the patient, in whom no expressive or receptive dysphasia could be found, misnamed objects when they were presented to him tactually, whereas he almost always gave the correct name when they were presented visually or auditorily; (2) the naming disturbance was identical when the object was presented to the left hand or to the right hand; (3) not only did the patient have no sensory deficit, but he could give unquestionable proof of correct tactile identification by using the objects presented to him tactually; (4) the defect appeared in the verbo-tactile as well as in the tacto-verbal direction; (5) it was not restricted to the name of the object since the patient was unable to describe, without making dysphasic errors, the morphology or usage of objects presented to him tactually; (6) the tacto-verbal dysfunction did not result from a tacto-visual impairment. Computerized tomography scans showed that: (1) there was no evidence suggesting a lesion of the right hemisphere, nor of the corpus callosum; (2) the left lesion involved the angular gyrus, the posterior part of the second temporal convolution, the inferior longitudinal fasciculus, the geniculostriate fibres and some fibres of the tapetum.

Agnosia

The cytoarchitecture of the inferior colliculus in the cat. A stereological approach.

The present study gives an histometric analysis of cells in the different subdivisions of the inferior colliculus. The use of principles and methods of stereology allows the definition of various cellular parameters, i.e. nuclear and cell volume, nuclear and cell profile areas, nuclear diameter, volume proportion of perikaryon, nuclear/cytoplasmic volume ratio and nuclear packing density. Our data confirm the existence of at least 3 parts in the inferior colliculus of the cat, namely: the ventral, the dorso-medial and the lateral parts. We furnish the various parameters which permit the characterisation of cells in these different parts. The dorso medial part or region appears to be composed of numerous cells characterized by their small volume and their high nuclear/cytoplasmic volume ratio. The ventral region seems to be distinguished by its scattered cells, characterized by their large volume and their low nuclear/cytoplasmic volume ratio, whereas the lateral region appears as an intermediate one with scattered cells of low volume. It seems notable that these cytoarchitectonic subdivisions fit well with the functional subdivision since the dorsomedial region receives cortical fibres, the ventral region receives cochlear fibres and the lateral region receives both cortical and cochlear fibres.

Animals

Clinical consequences of corticectomies involving the supplementary motor area in man.

Three patients with well-mapped, circumscribed ablations of the medial part of the frontal lobe are reported. A specific clinical evolution in 3 stages was observed: (1) post-operatively there was global akinesia, more prominent contralaterally, with an arrest of speech; (2) recovery occurred suddenly but even then there was severe reduction of spontaneous motor activity contralaterally, an emotional type facial palsy and a reduction of spontaneous speech; (3) long after the operation the only sequela was disturbance of the alternating movements of the hands. The anatomical basis of these disorders appears to be a lesion of the supplementary motor area (SMA). Three main points have been discussed, namely: (1) the nature of the motor disorder which may be a disturbance of the function of the SMA in initiating and sustaining spontaneous and automatic motor activity; (2) the nature of the arrest of speech which appears not to be aphasic; the studies reported in the present paper do not support a left cerebral dominance for the SMA as suggested by previous studies; (3) the method of clinical examination appears to be important in distinguishing between spontaneous and voluntary motor and speech performance. Differences in method may account for differences between our findings and those reported in previous studies.

Adolescent

[Typology of the cells of the bulbopontine reticular formation].

The network analysis methods have been applied to study the neurons of the medial bulbo pontine reticular formation in the cat. The bifurcation ratio allows isolation of two different cellular patterns: collateral branched cells or CB type, and at random pendant vertices dichotomously branched cells or DA type. The morphologic features of CB cells lead to the assumption that these cells have an integrative function. The topographic distribution of the two cells types seems to vary in the different parts of the reticular formation and should argue for the fact that the reticular formation represents an aggregation of several discrete anatomical units.

Animals

Scanning transmission and conventional electron microscopic observation of previously identified protoplasmic astrocytes. A preliminary study.

Two different types of protoplasmic astrocytes were studied by scanning transmission and conventional electron microscopy in order to determine the exact nature of the aspect described by Chan Palay and Palay as velate astrocyte. This study provides new data about the usefulness of S.T.E.M and brings into question the results of the Palays.

Animals