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H Goller

Publications and source records attributed to H Goller.

At least 19 recordsLinked to original sources
PubMed2000

Characterization of an extremely motile cellular network in the rotifer Asplanchna spp. Structure, kinetics, and the cytoskeleton.

The pseudocoelomic body cavity of the rotifer Asplanchna spp. contains free cells that form a highly dynamic, three-dimensional polygonal network of filopodia. Using video-enhanced differential interference contrast microscopy, we have qualitatively and quantitatively characterized the motion types involved with network motility: (1) filopodial junctions are displaced laterally at 10.52 +/- 0.46 microns/s; (2) free-ending filopodia form and extend at rates of 8.77 +/- 0.40 microns/s, until they retract again at 7.23 +/- 0.87 microns/s; (3) filopodial strands fuse either laterally or tip to the lateral side. The combination of these motion types results in enlargements, diminutions, and extinctions of filopodial polygons, and in the formation of new polygons. Moreover, there is intense and fast (5.11 +/- 0.28 microns/s) particle transport within the filopodial strands. The organization of the cytoskeleton in filopodia was examined by electron microscopy and by labeling with fluorescent-tagged phalloidin. Filopodia contain several microtubules that are often organized in a bundle. Moreover, F-actin is present within the filopodia. To characterize which of these cytoskeletal systems is involved with cell and organelle motility, we have examined cell dynamics after incubations with colchicine or cytochalasin D. The results of these pharmacological experiments provide evidence that microtubules are required for both cell and organelle motility, but that actin filaments contribute to these phenomena and are required for the structural maintenance of slender filopodia.

Animals↗
PubMed1995

[Development and cell differentiation in the nucleus nervi hypoglossi in cows].

Based upon light- and electron-microscope examinations, the ontogenetic development of the nucleus of cranial nerve XII is documented. At 1-cm crown-rump length (CRL), the caudal pole of the nucleus nervi hypoglossi forms a uniform cell column with the cornu ventrale of the spinal cord. During this period, its caudal area shows signs of cellular degeneration. From 3.5 cm CRL onward, all nuclear groups can be identified. At 53 cm CRL, they correspond to the pattern as described in the adult brain. Electron-optically, at 2.5 cm and 3.6 cm CRL, the nucleus of cranial nerve XII exhibits a close relationship to the matrix layer which consists of elements of dark nuclei. The hypoglossus nucleus is composed of dark and light cell types. It is the latter type that represents the presumptive neuron; it shows an increased ultrastructural differentiation from 2.5 cm CRL onward.

Animals↗
PubMed1994

[Development and cell differentiation of the vestibulocochlear nuclei in cattle].

Based upon light- and electron microscopic examinations (50 embryos ranging from 1 to 53 cm crown-rump-length, CRL) the origin of the nuclei of the cranial nerve VIII is described with special regard to neurogenesis. The ventricular matrix lateral to the sulcus limitans represents the alar plate with its sensory areas. Up to 2.7 cm CRL migrating neurons from the vestibular nuclei can be detected, the bigger neuronal elements of which are the early formed lateral vestibular nucleus. From 6.7 cm CRL onward all nuclear groups of the vestibular nerve can be identified. At 1 cm CRL the recess plate represents the primordium of the cochlear nuclear complex. Identification of the definitive nuclei is possible at 3.8 cm CRL. Subsequently from 7.6 cm CRL onward the process of lamination can be observed in the dorsal cochlear nucleus. Due to the proceeding maturation the nuclei of the cranial nerve VIII correspond at 53 cm CRL topographically and cytologically to the characteristics of adult animals. Electron microscopic examinations are documenting characteristic features of cytogenesis of sensory neurons (vestibular nucleus) during early embryonic stages (2.5 cm and 3.6 cm CRL). At 2.5 cm CRL the elements exhibiting features of migrating neurons are predominating, whereas at 3.6 cm CRL an increased differentiation is typical for neurons localized in their ultimate position. At this stage synapses can be identified for the first time.

Animals↗
PubMed1992

[Early development and cell differentiation of the parasympathetic vagus-glossopharyngeal nucleus in cattle. Light and electron microscopic studies].

The early development, differentiation of the cell and cell migration of the nucleus parasympathicus nervi vagi et glossopharyngei were examined by light microscope in 32 bovine embryos with crown-rump-lengths (CRL) ranging from 1 cm to 53 cm. During this period the nucleus is being enlarged 6 to 7 times and the size of the cell increases to 35-40 microns. The ultrastructure during the differentiation of the cell is shown electron microscopically in embryos with CRL of 2.5 cm and 3.6 cm. Several layers of matrix cells arise from the neuroepithelium of the neural tube by mitosis. They migrate in the shape of dark nucleated cells into the parasympathetic cell column. With advancing age of the embryos the number of cells with light nucleus increases. They represent the presumptive neurons. In embryos of 2.5 cm CRL their cytoplasm surrounds the nucleus on three sides in the shape of a narrow rim while on the fourth side it is enlarged into an outgrowing process. In this process a smaller number of organelles and their preliminary stages appears. Their number is significantly increased in embryos of 3.6 cm CRL and they can be seen throughout the growing process. In the following stages of maturity cytological development proceeds. In embryos of 53 cm CRL topographical and cytological data are comparable to those in adult animals.

Animals↗
PubMed1992

[Development and cell differentiation of the motor nucleus of the facial nerve of cattle].

The early development, cell-migration and cell-differentiation of the nucleus motorius nervi facialis were studied in 32 bovine embryos with a CRL of 1 to 53 cm by light microscopical techniques. The ventro-medial cell column, a transitory embryonic formation, can be regarded as the origin of the nucleus. From there migrating cells can be demonstrated up to a CRL of 2.7 cm. With 3.8 cm CRL the cells are confined to their definitive location. From 5 cm CRL onwards a subdivision into 4 subnuclei can be seen. By succeeding maturation processes the nucleus of fetuses with 53 CRL acquires the topographical and cellular appearance of mature animals. With the electron microscope the cell-differentiation of the early stages (2.5 and 3.6 cm CRL) was demonstrated. Additionally the ventro-medial cell column was studied. The vertical columnar organisation of the neurons of the nucleus facialis shows besides longitudinal orientated guiding structures the migration process which is taken place at a CRL of 2.5 cm. Synaptogenic cell contact are seen from 3.6 cm SSL. At this stage the migration of cells has come to an end.

Animals↗
PubMed1992

[Fine structure of the raphe nuclei of sheep and goats].

The medullary raphe system of sheep and goat can be divided in the solitary nuclei raphe magnus and pallidus besides the impaired Nucleus raphe paramedianus. The nucleus raphe magnus begins in the caudal end of the medulla oblongata running far to the pons. On the other hand you can follow the nucleus raphe pallidus and paramedianus only in distinct area near the obex. Different types of neurons are isolated and described in light- and electronmicroscopical investigations. All three nuclei are poor of synapses.

Animals↗
PubMed1991

[The fine structure of the nucleus of the hypoglossal nerve of sheep and goats].

In the small domesticated ruminants the nucleus of the hypoglossal nerve is situated in close relationship to the median line in the middle of the elongated medulla. The nucleus is divided by the obex into a rostral and a caudal portion. In the sheep, four distinct subnuclei can be recognized, whereas in the dwarf goat great variations in the arrangement of cell groups exists. In both animals large and medium sized neurons are observed. The large neurons are characterized by densely packed small organelles. The medium sized neurons vary between a pale and an electron dense type. According to the size and morphology of the vesicles three types of synaptic contacts can be differentiated. Synapses of type 2 contain clear round and flattened vesicles and are partially accompanied by subsurface cisterns.

Animals↗
PubMed1991

[Fine tissue studies of the nerve supply to the dental pulp in domestic sheep (O. ammon aries Linné, 1758)].

The nerve supply of the pulp was investigated in 17 sheep of various breeds and age groups belonging to both sexes, using light and electron microscopy. The following results were obtained: The dental pulp of sheep is supplied with myelinated and unmyelinated nerve fibres. The subodontoblastic plexus of Raschkow, as found in man, is absent in sheep. Single axons may be found in the predentine between the odontoblasts and near Tomes' processes. The rare occurrence of both subodontoblastic nerve fibres and cells of the immune system in the ovine pulp is discussed in relation to evolutionary processes, in light of the fact that sheep are relatively resistant to caries.

Animals↗
PubMed1990

[The fine structure of the nucleus of the facial nerve of sheep and goats].

The nucleus of the facial nerve in sheep and goats measures 4 to 6 mm and is divided into 4 groups (dorsal, medial, lateral, intermediate). Electronmicroscopically 5 neuronal types and 4 classes of synapses could be detected. Differences between the species are reduced to the arrangement of the rough endoplasmic reticulum and number of axo-somatic synapses.

Animals↗
PubMed1988

[The ultrastructure of the nucleus of the solitary tract of the sheep and goat].

The sensory nucleus of the IXth and Xth cranial nerve in sheep and goat takes a position in the middle of the elongated medulla forming a bilateral symmetric cell column. Neighbouring the canalis centralis dorsolaterally the caudal segments of both nuclei are connected in the raphe region by a subnucleus commissuralis. The solitary tract defines the nucleus in its lateral extension. The area postrema limits the rostral pole from the surface. Two distinct types of neurones are observed in the light and electron microscope. The small neurones show a paucity of organelles and an invaginated nucleus. According to their synaptic density three variations of small neurones could be distinguished. The large neurones are more compact in their cytoplasmic organisation. According to their size and morphology of vesicles five types of synaptic boutons could be differentiated. Most of the profile of the perikarya is surrounded by astrocytes and their extensions.

Animals↗
PubMed1988

[Cytoarchitecture and ultrastructure of the mesencephalon trigeminal nucleus of the domestic chicken].

Position, form, dimensions and fine structure of the mesencephalic trigeminal nucleus of the domestic chicken are described. It consists of round to oval large and rare medium sized pseudo-unipolar neurons. The Nissl bodies are scattered throughout the perikaryon of both cell types in a dust like way. Electronmicroscopically the neurons are characterized by numerous neurofilaments, lysosomes and mitochondria. The cell surface shows a moderate distribution of synapses, and few somatic spines and invaginations of the plasmalemma.

Animals↗
PubMed1980

[Light and electron microscope study of the cerebellar cortex in the cow, sheep and goat].

In order to investigate the fine structure of the cerebellar cortex of domestic ruminants, tissue specimen were taken of the Lingula, Declive, Nodulus, Lobus paramedianus and Flocculus of 30 cows, sheep, and goats. The following techniques were used: Luxol-Fast-Blue and Nisslstaining, Bodian and Golgi impregnation according to BUBENAITE and to KEMALI (1976). Electronenmicroscopically, differences between these species were seen only in the thickness of the three layers and in the size and topography of the 7 different cells and the fibres of the cerebellar cortex. In contrast to other species, soma and fibres of the Purkinjecells often contained numerous lamellar bodies. As in other animals the granular endoplasmic reticulum is arranged in form of nuclear caps.

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