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PubMed1977

Anomalous pulmonary venous connection of entire left lung with intact atrial septum.

Three cases of total unilateral pulmonary venous connection of the left lung with intact atrial septum are described. All patients were acyanotic and had findings of volume overload of the right side of the heart. An anomalous vertical vein in the superior mediastinum and large pulmonary arteries were visible on the plain chest radiograph, similar to what is seen in cases of total anomalous pulmonary venous connection. Selective pulmonary angiography delineated the anomalous connection of the left pulmonary veins and documented the absence of an atrial septal defect.

Adult↗
PubMed1977

Anatomy of interhemispheric connections in the visual system of Boston Siamese and ordinary cats.

In Siamese cats, previous studies have shown that a genetic mutation causes retinogeniculate fibers in each eye which arise from the temporal retina representing the 20 degrees of ipsilateral visual field adjacent to the vertical meridian to cross aberrantly in the optic chiasm, thereby terminating in the wrong lateral geniculate nucleus. The abnormality is expressed subsequently at the level of the visual cortex. This paper presents anatomical evidence that the pattern of commissural visual connections in the "Boston" variety of Siamese cat also is highly abnormal in comparison to that of ordinary cats. The topographical distribution of neurons supplying visual fibers to the splenium of the corpus callosum was studied in Boston Siamese and ordinary cats using the method of retrograde transport of horseradish peroxidase (HRP) following localized cortical injections made through a recording micropipette. In ordinary cats, after an HRP injection at the border between cortical areas 17 and 18, which represents the vertical meridian of the visual field, HRP-labeled cells in areas 17 and 18 of the opposite hemisphere were found only immediately adjacent to the 17-18 border, thus confirming the results of previous investigations. In Boston Siamese cats, the border represents a region in the ipsilateral visual field roughly 20 degrees away from the vertical meridian, and the vertical meridian representation is displaced to sites within areas 17 and 18 proper. When HRP was injected at the 17-18 border, labeled cells in the opposite hemisphere were located well within area 17 near the suprasplenial sulcus, and also well within area 18; few labeled cells were found at the 17-18 border. When an HRP injection was placed at the vertical meridian representation, again few HRP-labeled cells were found at the opposite 17-18 border, but instead most were found in area 17 slightly medial to the border, and in area 18 slightly lateral to it. Thee findings were complemented in an autoradiographic study in which orthograde transport of tritiated proline after a localized cortical injection was used to demonstrate the distribution of callosal terminals. Thus the pattern of callosal connections revealed in Boston Siamese cats, although anatomically different from that of ordinary cats, was nevertheless consistent with the proposal that cortical sites representing similar visual field coordinates in each hemisphere are appropriately interconnected via the corpus callosum. The laminar distribution of callosal connections was examined briefly. Layer III pyramidal cells of areas 17 and 18 supplied the majority of terminals to the opposite 17-18 border. Pyramidal cells of Layers II and VI, and Layer IVa in area 18, made a smaller contribution. In areas 17 and 18, the same cortical layers (II, III, and VI; and IVa in 18) were again the major sites of callosal termination. A clear projection to the base of layer I was also noted. The laminar distribution of callosal connections in ordinary and Boston Siamese cats were not substantially different.

Agenesis of Corpus Callosum↗
PubMed1978

The teratogenic effects of 5-fluoro-2-desoxyuridine (F.U.D.R.) on the Wistar rat fetus with particular reference to cleft palate.

The teratogenic effects of 5-fluoro-2-desoxyuridine on Wistar rat fetuses were studied macroscopically, microscopically and ultrastructurally. In no case did palatal shelf elevation occur, and a palatal shelf elevating force could not be demonstrated in freshly-removed fetuses. The shelves, like the connective tissues generally, showed clear evidence of depressed mucopolysaccharide synthesis. The shelves eventually ossified in the vertical position, and in some cases their free edges fused with the lateral wall of the oral cavity (palato-oral fusion). The results were consistent with the mucopolysaccharide-turgor hypothesis advanced by the author in a previous paper to account for normal shelf elevation. Phocomelia, brain and limb bud haemorrhages, gross subcutaneous oedema, hyperextension of the cranial base, fused vertebrae, detached epithelia, bizarre brain abnormalities (including some remarkable attempts at neural reconstitution) and growth and ossification of the mandible in the virtual absence of Meckel's cartilages were also noted in these fetuses.

Abnormalities, Drug-Induced↗
PubMed1979

Anatomy of musculus levator veli palatini in the 15-week human fetus.

The morphology of musculus levator veli palatini in the 15-week fetus was analyzed using 30-micrometer subserial sections. The sample included 26 specimens, of which 9 each were sectioned coronally and sagittally while 8 were sectioned in the transverse plane. At this stage of development m. levator veli palatini takes a general attachment to the precursor of the petrous part of the temporal bone, and, in some cases, auxiliary attachments to the auditory tube complex were also observed. At its origin, the muscle is located anterior to the tube. It then runs medially, passing beneath the auditory tube prior to entering the velum. As it nears the region of the lateral pharyngeal wall, a small fascicle trails posteriorly and inferiorly to the main muscle mass and occasionally runs into the upper margin of m. constrictor pharyngis superior. The levator muscle is more localized within the velum at this stage of development than it has been reported to be in the adult, being confined here to the central third of the soft palate. Most of the fibers of the muscle appear to form a sling within the central 20% of the velum, although some were seen to take attachment to loose connective tissue and the palatine raphe. Upon its entry into the velum, m. levator veli palatini is intersected vertically by bundles of both mm. palatoglossus and palatopharyngeus.

Female↗
PubMed1976

[Vertical vergence pathways].

Two pathways for vertical vergence probably exist: the cortical one carrying a psycho-optical reflex, the other sub-cortical connected to the vestibular apparatus and more probably to the otolith system. The sub-cortical pathway is essentially a vestibulo-cerebellar oculomotor pathway; but in addition there certainly exist direct vestibulo-oculomotor connections and long tracts passing through the interstitial nucleus of Cajal and the reticular formation.

Afferent Pathways↗
PubMed1978

Horizontal cells of the turtle retina. I. Light microscopy of Golgi preparations.

In Golgi preparations of turtle retina, four types of horizontal cells were observed and their morphological characteristics determined in vertical thick sections, whole mount preparations, and reconstructions from serial 1-micrometer sections. H1 consists of a nucleated, stellate cell body (H1CB) and an irregular, tuberous axon terminal (H1AT) connected by a slender axon. Both parts of these cells make contact with receptor cells. H1CB's appear to correspond to "L2-type cells" while H1AT's correspond to "L1-type cells" described in the physiological literature. H2 and H3 are axonless stellate cells which are similar to one another in vertical profile and may occasionally appear similar in horizontal view. In general, the dendritic tree is more densely branched and the density of receptor cell contacts is higher for H2 than for H3. H2-type cells may correspond to "R/G C-type cells." H4 is also an axonless stellate cell type which is smaller than H2 or H3 at equivalent retinal locations. The dendritic fields of H1CB's vary widely, but systematically, in size and shape over the retina. Their size is inversely related to receptor cell density, and the shape of the dendritic tree varies from roughly circular in the central area to elliptical in the periphery of the retina.

Animals↗
PubMed1975

Variability of dermal elastin visualized ultrastructurally with iron hematoxylin.

The Verhoeff iron hematoxylin-lead citrate (VIH-LC) method demonstrated vertical elastic fibers that were often composed only of microfibrillar component extending into the epidermal basement membrane in human skin. These fibers connected with a network of trabeculae composed of microfibrils and elastin fibrils in varying proportions. The large elastic fibers in the deep two thirds of the dermis consited mainly of compact bundles of small elstin fibrils in infants and of solid elastin cores with a fimbriated periphery in adults; Dermis of a 6-month-old fetus contained very few small elastic fibrils except around blood vessels. Skin of an elderly subject revealed exteme proliferation of unusual reticulated elastic fibers in various areas and disclosed abnormal nodules of elastin or collagen fibrils in finely particulate matter. Small elastin fibrils, abundant microfibrils, and intermixed individual collagen fibrils comprised an adventitial collar between sweat glands and fibroblasts. Elastin fibrils were absent from this collar in the fetus and increased with the subject's age. A permanganate-high iron diamine sequence appeared to impart density to the microfibrillar component of elastic fibers.

Adolescent↗
PubMed1979

A Golgi study of the ventral tegmental area of Tsai and interfascicular nucleus in the rat.

The ventral tegmental area of Tsai (VTA) and interfascicular nucleus of the adult rat brain has been studied with two variants of the Golgi method in three planes of section. Neurons were studied in relation to the cytoarchitectural groupings of the VTA. Dendritic organisation and dendritic fields were mapped out for each cytoarchitectural subgroup and cell types within each subgroup were classified on the basis of cell size and dendritic morphology. In each subnucleus of VTA, neurons had distinct characteristics. In nucleus paranigralis neurons were small to medium in size and their dendritic fields organised in an approximately horizontal plane orientated in an anteromedial direction and slanting dorsally over the interpeduncular nucleus and fossa. Neurons of the parabrachial group were small to medium sized with no preferential orientation. In nucleus linearis raphe caudalis small neurons were strongly orientated in the plane of the nucleus in a dorso-ventral direction slanting forwards. Neurons in the interfascicular group were small to very small and their maximum dendritic extents were seen in the horizontal plane. In frontal section they formed a compact ball of cells in the midline and were separated on either side from the larger neurons in the medial edge of nucleus paranigralis. In general VTA neurons tended to fall into one of two morphological categories. Type 1 were small to medium, and had two to four primary dendrites which divided into varicose secondary dendrites. Type 2 were medium sized, with two to five primary dendrites. Both primary and secondary dendrites and the cell soma of Type 2 neurons were moderately spiny. Secondary dendrites were not varicose. Forms also occurred which were intermediate between Types 1 and 2. In the nucleus paranigralis, Type 1 was more common medially, while Type 2 was more common laterally, particularly in the ventrolateral paranigral region. Only neurons of Type 1 were seen in nucleus linearis raphe and interfascicular nuclei. Local axon circuits were observed to arise from the primary dendrites of Type 1 neurons and to ramify close to neighbouring neurons. Axon swellings from such circuits were observed to make apparent contact with primary dendrites of nearby neurons and clusters of axon swellings were observed near cell somas of neighbouring impregnated neurons of similar type. The results are discussed and particular attention is paid to the similarities and differences between VTA and the substantia nigra pars compacts (SNC). The major difference appears to be that, whereas in SNC dendrites are organised in vertical as well as horizontal planes, in the VTA no long ventrally directed dendrites were observed. Combining these results with known cytoarchitecture and connections of VTA and SNC, it appears that fundamental differences occur between VTA and some neurons of the SNC, both in the nature of their morphology and intrinsic organisation, and in the organisation of their efferent and afferent connections.

Animals↗
PubMed1978

The organization of area 18 in the monkey. A Golgi study.

The organization of area 18 in monkey has been studied in Golgi preparations. In layer III large pyramidal cells with profusely ramified basal dendritic arbors are identified. They probably represent one of the major components originating association connections. Layer II and the upper part of layer III contain cells with spine-free dendrites having axons forming long bundles descending vertically to layers IV and V. Layer IV is characterized by the presence of granular cells with local axons and small pyramidal cells with ascending recurrent axons. Layer V contains various types of pyramidal cells including giant pyramidal neurons. The mean number and distribution of dendritic spines along apical shafts were computed in four varieties of pyramidal cells. Several neuronal parameters pertaining to the length of axons and dendrites were calculated. Three-dimensional aspects of cells were analyzed by means of a computer program which permits neurons to be displayed as perspective views from various positions. Attempts were made to correlate the present description with previous observations on this and other cortical visual areas.

Animals↗
PubMed1979

Surfaces with steep variations in depth pose difficulties for orientationally tuned disparity filters.

Surfaces possessing steep variations in depth present severe difficulties for orientationally tuned filter models of stereopsis. These difficulties are discussed in connection with a random-dot stereogram depicting a surface with steep horizontal corrugations. As expected on theoretical grounds, we find that a vertical +/- 45 degrees orientationally filtered version of this stereogram cannot be fused. Moreover, it is demonstrated that a horizontal +/- 45 degrees filtered version can be fused only with difficulty and its stereo percept is poor compared to that of the unfiltered original. It is concluded that orientated filters seem ill-designed to mediate the extraction of disparity cues, at least in the cases under consideration.

Depth Perception↗
PubMed1977

[Acquired fibro-keratoma. Report of 8 cases].

The acquired fibro-keratoma is a benign fibro-epithelial tumor of acquired nature. I was set apart as a distinct entity in 1968 by Bart et al. who named it "acquired digital fibro-keratoma". It is predominantly, although not exclusively, located on the fingers and toes, near the phalangeal joints. The authors report 8 personal cases and make a short general review of the disease. The lesion is slightly prominent, well defined and surrounded by a hyperkeratotic collar. It protrudes on the surface of the skin much like a hernia. Histologically, it is a dermo-epidermal tumor. There is a proliferation of connective tissue under the papillomatous, hyperacanthotic and orthokeratotic epidermis. The mature collagen bundles, voluminous fibroblasts and numerous enlarged capillaries are parallel to the vertical axis of the tumor. The acquired fibrokeratoma must be differentiated from other cutaneous tumors, particularly fibromas and Koënen's tumors. The etiology is unknown. However, it was found in some cases that a trauma had contributed to the development of the tumor. The only possible treatment is surgical excision.

Adult↗
PubMed1977

Abnormal interhemispheric connections in the visual system of Boston Siamese cats: a physiological study.

In the normal cat most visual fibers in the splenium of the corpus callosum are concerned with a representation of the vertical meridian of the visual field. These fibers for the most part originate from cortical regions forming the border between adjacent architectonic areas, such as the anatomical 17-18 border. Due to a genetic mutation in Boston Siamese cats, the anatomical 17-18 border now represents a region in the ipsilateral visual field roughly 20 degrees away from the vertical meridian, and the representation of the vertical midline is displaced from the border to regions within areas 17 and 18 proper. Do visual fibers in the Boston Siamese cat corpus callosum originate, as in normal cats, from the 17-18 border even though the vertical meridian is no longer represented there? The present paper deals with this question from a physiological standpoint. Single visual fibers in the corpus callosum of 11 Boston Siamese and two normal cats were recorded using extracellular microelectrodes. Receptive fields were mapped and their positions used to infer the likely cortical site of origin for each fiber. In confirmation of earlier findings, most callosal receptive fields in the normal cat were closely apposed to the vertical meridian, as would be expected if only those visual cortical regions which represent the vertical meridian, such as the border between areas 17 and 18, contribute to the corpus callosum. In Boston Siamese cats, however, an abnormally large amount of visual field was represented in the corpus callosum, with some receptive fields located as far as 25 degrees away from the vertical meridian. The representation of the vertical meridian was nevertheless substantial. The present findings suggest, therefore, that in Boston Siamese cats callosal fibers do not originate solely from the boundary regions between adjacent cortical areas, such as the anatomical 17-18 border, but originate also from other cortical regions, especially the vertical meridian representation, regardless of their location with respect to such boundaries.

Animals↗
PubMed1979

Thalamic projections to area 17 in a prosimian primate, Microcebus murinus.

Electrophysiological recording of single neurons was used to describe the representation of visual space in area 17, and the technique of retrograde transport of horseradish peroxidase (HRP) was applied to relate these results to projections from the thalamus in the prosimian primate Microcebus murinus. The visuotopic organization of area 17 was found to resemble that of other primates. On the dorsal surface, the border of area 17 corresponds to the representation of the vertical meridian. Proceeding medially across the surface the location of receptive fields descends along the vertical meridian, while moving caudally receptive fields progress temporally. Most of the dorsolateral surface is devoted to central vision and corresponds to a well developed area centralis. Following HRP injections in striate cortex, columns of labeled cells were found in the dorsal lateral geniculate (dLGN) extending orthogonally across all six layers. These columns run in a general ventrodorsal and caudorostral direction, parallel to a line connecting the cellular discontinuities corresponding to the optic disc. These discontinuities are present in magnocellular layer 1 and parvocellular layers 5 and 6, thus receiving from the nasal retina of the contralateral eye. The representation of the vertical meridian is situated in the ventromedial portion of the dLGN, and the monocular field is represented in the dorsal extremity. Anterior dLGN projects to the calcarine fissure (lower field) and posterior dLGN projects to the ventral surface of the cortex (upper field). Extrageniculate input to area 17 was found to originate from the pulvinar. HRP labeled cells were located in two distinct divisions of this nucleus, the cytoarchitecture of which is described. In addition, projections to occipital cortex were found to arise from the intralaminar nuclei.

Animals↗
PubMed1977

Physiopathological variations in the mechanical properties of skin.

An evaluation of the rheological properties of skin is provided by measuring "in situ" the ability of skin to withstand vertical forces of extension. In physiological conditions the biomechanical parameters are reproducible and related to age, sex, skin thickness and the microarchitecture of the connective tissue studied by scanning electron microscopy. These observations shed some light on the structure-function relationship of the fibrous framework of the connective tissue. Variation in the biomechanical parameters can be used to substantiate clinical diagnosis and to monitor the evolution and the therapy of various diseases of the connective tissue.

Adolescent↗
PubMedDate not supplied

[Reactions of the directionally sensitive optical interneurons of insects to movement of a two-dimensional pattern].

The reactions to movements of two-dimensional patterns with the same average spatial period were compared in electrophysiological experiments. Directionally-sensitive neurons in connectives of dragonflies (fam. Libellulidae) were 1.5--2 times more sensitive to movement of "dissected" patterns (checkerboards, lattice of circles, stochastic pattern) than to vertical stripes. The power of optic signal in high-frequency domain in dissected patterns is 1.4--1.8 times higher, than in a striped pattern. It is assumed that high-frequency spatial filtering in dragonflies is provided by strong lateral inhibition in retinotopic projection. Dissected and striped patterns elicited identical reactions in directionally-sensitive neurons of the dronefly Eristalis tenax; the same was stated for the locomotory optokinetic reaction of the earty-boring dung beetle Geotrupes stercorosus.

Animals↗
PubMed1979

Importance of corpus callosum for visual receptive fields of single neurons in cat superior colliculus.

1. Section of the posterior two-thirds of the corpus callosum eliminates almost completely the response of superior colliculus (SC) neurons to stimulation of the contralateral eye in split-chiasm cats. On the contrary, the responsiveness of SC neurons to stimulation of the contralateral eye is not abolished by a transection of the posterior and tectal commissures leaving the corpus callosum intact. The callosal section also reduces the number of SC receptive fields abutting the vertical meridian in the ipsilateral eye of split-chiasm cats. 2. In cats with intact optic pathways, a similar callosal section abolishes the SC representation of the ipsilateral visual field in the ipsilateral eye and also reduces the number of receptive fields adjoining the vertical meridian in the same eye. In the contralateral eye, the SC representation of the ipsilateral visual field is reduced in extension to about one-fifth of that seen in cats with intact commissures. 3. The results suggest that the corpus callosum is the main pathway for cross-midline communication of visual information at not only the cortical, but also the midbrain level. The corpus callosum may subserve this function because it contains uninterrupted crossed corticotectal projections or because it transmits visual information from one hemisphere to contralateral cortical areas projecting ipsilaterally to SC. The latter hypothesis is more likely but, in any case, the findings imply that the lack of interhemispheric transfer of visual learning in cats with a chiasmatic and callosal section may depend on a midline disconnection of both subcortical and cortical visual centers. 4. The corpus callosum is also responsible for the representation of the ipsilateral visual field of the ipsilateral eye in the cat SC. The SC representation of the ipsilateral visual field in the contralateral eye is due, in minimal part, to direct retinotectal connections from temporal retina and, for the largest part, to the corpus callosum. 5. Finally, the corpus callosum contributes to the representation of the contralateral visual field near the vertical meridian of the temporal retina in both split-chiasm and normal cats. This is probably due to the scarcity of direct retinotectal projections from this part of the retina and to their supplementation by corticotectal neurons influenced by the callosal afferents.

Animals↗
PubMed1979

The morphology of the vertical and transverse intrinsic musculature of the tongue in the 15-week human fetus.

The attachments, courses and interrelationships of the transverse and vertical intrinsic muscle masses of the tongue were examined in 28 fifteen-week fetal specimens. Observations were made from 30-micron sections cut through the tongue in one of the three standard planes of section. Both sets of muscululature are qualitatively well-developed by this time period in fetal life. The transverse fibers were found to occupy the entire length of the tongue. They attach to the lamina propria of the lateral aspect of the body of the tongue and, in the root, to perimysial and adventitial connective tissue. In addition, some fibers were observed to be confluent with the mm. palatoglossus, tonsilloglossus and pharyngis superior. Medially, transverse fibers were found for the most part to terminate in the dense ventral aspect of the median septum. Vertical fibers are present from a point slightly posterior to the tip of the tongue to the level of the foramen cecum, beyond which they become sparse. All vertical fibers attach superiorly to the dorsal lamina propria. In the free part of the body, their ventral attachment, likewise, is to lamina propria. In the middle part of the tongue and, to a greater extent, in the root (as the inferior and lateral free surface decreases) these fibers attach in either the fascial plane underlying the transverse component or to the perimysium of longitudinally-running muscle bundles.

Connective Tissue↗
PubMed1976

Semi-automatic apparatus for determination of the consistency of microbiological culture media and gel-forming substances (author's transl).

The gel strength is an important factor in the production and preparation of microbiological culture media on the basis of agar-agar, silicagel and gelatine. There is an evident interest in a standardization of this parameter which can influence the number and the form of the colonies, the results of antibiograms and other tests based on diffusion. The apparatus described can be used for simultaneous determination of the gel strength and the elasticity of microbiological and industrial gels. The construction consists of an electromotor-driven supporting table for the specimen and a pressure measuring device. In operation, the gel is moved vertically with a constant speed against the probe of the pressure device. The pressure exerted on the surface of the gel can be read from a dial connected with the probe as well as the pressure at which the surface of the gel is being disrupted (breaking point, gel-strength pressure). The apparatus can be purchased under the name Gelomat from Heinrich Bareiss, 7931 Oberdischingen, West Germany (see Fig. 1 and 2). The results of the measurements can be influenced by various factors such as concentration of the gelating compound, composition and pH of the solvent, time and temperature at which the gel is held before, during and after plate pouring, surface (dry or wet) and heigth of the gel sample, method of mesurement, etc. To account for all these factors, a standard method of measurement is described. The apparatus has a sensibility of ca. 2 g, can measure a gel strength between 0 and 200 g with the standard equipment, and has a standard deviation of less than 1.35 for microbiological agar-agar gels (see Tables 2-4). The time needed for one determination is 40-60 seconds. Compared with other instruments for the same purposes, the Gelomat has following advantages: Simple and handy use, good sensitivity and reproducibility, capability for simultaneous measurement of gel strength and gel elasticity. In the last 4 years, this apparatus has been used with good results in more than 10,000 routine determinations

Bacteriological Techniques↗