bluuebunny/crossref_metadata_2025 huggingface dataset:
Projections of the visual cortex to the lateral geniculate and posterior thalamic nuclei in the cat
Authors: Niimi Kahee , Kawamura Syosuke , Ishimaru Shizuo
Published: December 2004

Fiber degeneration in the cat following lesions of various parts of areas 17, 18 and 19 was traced to the lateral geniculate and posterior thalamic nuclei by the method of Nauta and Gygax. Area 17 lying in the lateral and posterolateral gyri projects to the most medial parts of laminae A, A1 and central interlaminar nucleus (NIC). Area 17 in the suprasplenial gyrus sends fibers to the medial and middle parts of laminae A and A1 and the underlying part of NIC, while that in the splenial gyrus gives off fibers to the dorsolateral and ventrolateral parts of laminae A, A1 and NIC. These data indicate that there is a mediolateral organization in the projection from area 17 to the dorsal lateral geniculate nucleus. A topical organization exists also in the anteroposterior direction; the anterior, middle and posterior parts of area 17 project to the corresponding portion of the dorsal nucleus. Area 18 gives rise to fibers that pass between the medial interlaminar nucleus (NIM) and lamina A1 into the dorsolateral part of NIM, the medial part of NIC and the medial ends of laminae A and A1. The projections of area 18 to the dorsal nucleus are also organized in the anteroposterior dimension. Area 19 sends fibers to the major part of NIM, except to its most ventral and dorsolateral parts, and to the medialmost parts of NIC and lamina B. The majority of these fibers run along the medial aspect of NIM, but a few fibers pass ventrolaterally between NIM and lamina A1. It should be mentioned that NIM receives fibers not only from area 19 in the lateral and the posterior suprasylvian gyri, but also from area 19 in the medial cortex. As with areas 17 and 18, the corticogeniculate projections of area 19 are organized in an anteroposterior dimension.

The ventral lateral geniculate nucleus also receives fibers from areas 17 and 19. The anterior part of area 17 projects only very few fibers to the ventral nucleus, but the posterior part gives off many fibers to the external layer of the nucleus. Area 17 fibers from the posterolateral gyrus are distributed in the dorso‐medial part of the external layer and those from the suprasplenial gyrus enter the ventral and medial portion of the layer. In contrast most of area 18 and that part of area 19 in the lateral gyrus project no fibers to the ventral nucleus. The other parts of area 19 give off fibers to the internal layer and the adjoining portion of the external layer of the ventral nucleus. There appears to be an anteroposterior organization of the projection of the visual cortex on the ventral nucleus. The posterior thalamic nucleus receives fibers from areas 18 and 19 and part of area 17. Area 18 sends fibers to the medial and ventromedial part of the posterior nucleus, while most of area 19 projects fibers to the dorsal and middle part of the nucleus. Area 17 lying in the upper portion of the posterolateral gyrus and the suprasplenial and splenial gyri projects to the dorsomedial and medial part of the posterior nucleus.
Studies on the developing cerebellum. II. The ultrastructure of the external granular layer
Authors: Del Cerro Manuel P. , Snider Ray S.
Published: December 2004

The ultrastructure of the external granular layer (EGL) of the rat cerebellum has been studied with special attention given to the changes occurring during its postnatal existence. Three periods are described: In the first period, lasting until day 5, the EGL is composed of a homogeneous population of germinal cells; the second period, lasting until day 17, is characterized by differentiation of neuroblasts which accumulate under the germinal cells forming the mantle zone. In the third period, the cell proliferation ends and the layer becomes progressively thinner and disappears by postnatal day 20. During these periods, the following cells have been identified: (A) germinal cells, ovoid or polyhedral and usually ciliated, have a comparatively large nucleus, a rim of cytoplasm, and an undetermined number of thin, long processes which persist during mitosis, although their fate during postmitotic differentiation was not established. (B) horizontal neuroblasts, with flattened nucleus and soma, are richer in organoids than the germinal cells, have neurotubules and thick lateral processes. (C) transitional bipolar neuroblasts resemble horizontal cells, except that most organoids, including the cilium migrate into the descending process. (D) A stage of apolar neuroblast has not been observed and there was no evidence of glial formation in the layer. A variety of cellular attachments are present, but synapses were not seen at any stage. At birth, the EGL adjacent to the pia mater is formed by EGL cells and their processes which are later replaced by the end feet of Bergmann glia which during a time exhibit giant mitochondria. Glial processes separate the EGL cells into columns and a neuropile is formed by these processes, and those of the EGL cells. The extension of the extracellular space is discussed as is the spontaneous degeneration of cells.
A stereotaxic atlas of the brainstem for Macaca mulatta in the sitting position
Authors: Smith Orville A. , Kastella Kenneth G. , Randall David C.
Published: December 2004

Attempts to use existing stereotaxic atlases of the lower brainstem of monkeys for the placement of microelectrodes in the cranial nerve nuclei of awake animals have met with little success. The relationship of these nuclei to the bony structures used for orienting the head are probably altered when the position of the body is radically changed from the horizontal to the vertical (sitting) position. The atlas presented is based upon Macaca mulatta monkeys sitting in position in a primate restraint chair. This standard orientation provides a necessary frame of reference for accurate localization of lower brainstem structures.
Anatomical aspects of the superior olivary complex
Authors: Strominger Norman L. , Hurwitz Jessica L.
Published: December 2004

The cytology of the superior olivary complex was studied in Nissl stained sections of eight human brainstems, including adult, infant and fetus, and in the brains of ten juvenile rhesus monkeys. The most prominent components of the superior olivary complex of primates were specifically investigated, i.e., the medial (SOM) and lateral (SOL) superior olivary nuclei. Cell counts of these segments were done in human brainstems. The adult SOM was comprised of an average of 11,428 (7,850–15,010) perikarya; the SOL contained an average of 3,923 (2,890–5,400) neurons. These findings indicate that the SOL contains as many cells as reported in other primates, and is not reduced. The SOL appears somewhat inconspicuous in the human because it is organized into as many as six clusters of cells rather than forming one well circumscribed configuration as in the monkey and cat.

The total cell population of the SOM together with the SOL was approximately the same on each side of individual brains. If one segment was larger on one side than the opposite side, the other segment was correspondingly reduced to maintain the relative symmetry. This suggests that a single mechanism controls the cell complement of at least these two segments of the superior olivary complex.
The developing caudate nucleus in the euthyroid and hypothyroid rat
Authors: Lu Elizabeth J. , Brown W. Jann
Published: December 2004

The basal ganglia are presently implicated in learning, and thyroid deficiency induced neonatally is known to affect mentation. The effects of such a deficiency on the developing caudate nucleus might be used to provide insight into structure and function of the normal subcortical brain, as well as possible influences of these extrapyramidal structures on mental retardation. Propylthiouracil was added to the diet of lactating rat dams and observations of the developing caudate nuclei of normal and hypothyroid rats were made at 8, 14, 20, 30 and 42 days by using various tissue stains and Golgi‐Cox preparations.

Seven different types of neurons were distinguished in the caudate nucleus. Differences in the size of cell somata and the varying morphology of axons and dendrites were criteria used to make distinctions. Normally, the nucleus acquires cytoarchitectural complexity during the first three postnatal weeks. Within this period, neuron incidence increases in the caudate neuropil with age while the germinal matrix density decreases. Neuron accumulation reaches a plateau after the third week and cell migration is essentially complete at the end of the first postnatal month as shown by computer analysis of Nissl stained cell counts. Branching of cellular processes, attainment of receptor spines and complexity of the fiber network also appeared during this period.

Retardation of structural development with thyroid hormone deficiency was shown by decreased numbers of neurons, inhibition of dendritic arborization, decreased numbers of dendritic spines and a reduced complexity of axonal plexuses. Thyroid deficiency delays cell migration during the first three weeks when compared to age‐matched normal controls. The lack of thyroid hormone does not appear to influence the size of neuron somata, and the extent of related dendritic fields, nor does hypothyroidism affect a specific cell type population. Generalized disturbances of caudate nuclear morphological maturation are caused by the deficiency. An apparent compensatory process, including a spurt of neural growth and differentiation, takes place in the period between days 14 and 30 in the deficient animals and a seemingly “normal” caudate cytoarchitecture is seen after the third postnatal week. Quantitative data, however, show that this rapid “catch up” process is inadequate.

The developmental imperfection of the caudate nucleus which persists might be a part of the underlying substrate for the mental retardation, disturbed motor performance and perceptual handicaps which are found in the human patient.
A Golgi study on the habenular nucleus of the cat
Authors: Iwahori Nobuharu
Published: December 2004

The habenular nucleus of kittens was studied using the rapid Golgi and the Golgi‐Kopsch silver impregnation methods.

The neurons of the medial habenular nucleus (MH) were classified into two types. The type I neurons, the main constituents of the MH, had piriform cell bodies with a mean diameter of 12 μm by 18 μm and two to five primary dendrites; dendrites had many spines. The type II neurons (14 μ 23 μm) were fusioform in shape and one to three primary dendrites arose from each pole of the cell bodies; dendrites had few spines. The axons of both types of neurons were traced into the fasciculus retroflexus Meynerti (FR), and intranuclear axon‐collaterals arose from axons of the type I neurons.

The neurons of the lateral habenular nucleus (LH) were divided into four groups. Type I, II and III neurons were projection neurons of large, medium and small size, respectively. The type I neurons (27 × 43 μm) with four to seven primary dendrites were located mainly in the rostral and ventral areas of the LH. The type II neurons (15 × 33 μm) with two to four primary dendrites, the main constituents of the LH, were distributed throughout the LH. The type III neurons (15 × 25 μm) with two primary dendrites emerging from each pole of the soma were localized to the mediocaudal areas of the LH. The vast majority of axons of these projection neurons passed ventrally or ventrocaudally to enter the FR; only a few axons of these neurons were traced into the stria medullaris thalami (SM). The type IV neurons (12 × 25 μm) were small cells with short axons, suggesting the existence of a neural circuitry intrinsic to the LH. Bundle formation and glomerular arrangement of dendrites were observed in the medium‐sized LH neurons.

The afferent fibers terminating within the MH coursed in the most medial part of the SM. These afferents were classified into medium‐caliber type I and fine type II fibers; both of these fibers emitted many intranuclear collaterals. There were also observed many fibers of passage which ran between the SM and FR, or between the habenular commissure (HC) and FR.

The afferent fibers to the LH were divided into three groups; afferents via the HC, ascending and descending afferents. Most of the descending afferents entered the LH through the SM; some of them traversed the LH to join the FR or HC, or to extend to the pretectal region. The vast majority of the ascending afferents entered the LH via the FR; some of them extended rostrally to enter the SM. Some fibers in the HC also terminated within the LH. In addition to these afferents, many fibers of passage were seen to run through the LH and to bridge over between the SM and FR, or between the SM and HC.
The organization of the facial nucleus of the brush‐tailed possum (Trichosurus vulpecula)
Authors: Provis Jan
Published: December 2004

The facial nucleus of the brush‐tailed possum has been studied using Nissl staining and the horseradish peroxidase (HRP) retrograde tracing technique. In Nissl stained sections the nucleus is seen to comprise five distinct subnuclei. Injections of HRP into individual facial muscle groups have shown that these subnuclei reflect the peripheral innervation pattern of efferents from this nucleus

Although in most cases, injection of HRP into a single facial muscle group resulted in the labelling of neurons in more than one facial subnucleus, the following subnuclei were most completely labelled subsequent to intramuscular injection of HRP: the dorsal intermediate subnucleus was labelled with HRP reaction product following injection of m. auricularis anterior; the middle intermediate subnucleus was labelled following injection of the muscle underlying the malar vibrissae; the ventral intermediate subnucleus was labelled following injection of the m. mentalis; the medial subnucleus was labelled following injection of the m. auricularis posterior; the lateral subnuleus was labelled following injection of the m. nasolabialis with HRP

In general there is a mediolateral representation in the facial nucleus of neurons innervating facial muscle groups which are found in anteroposterior succession along the head of the animal. Muscle groups found in dorsoventral succession on the animal are represented dorsoventrally in the facial nucleus.
Distinct auditory and lateral line nuclei in the midbrain of catfishes
Authors: Knudsen Eric I.
Published: December 2004

The catfish torus semicircularis (TS) comprises two major nuclei, which are specialized to process separately inputs of three acousticolateral modalities: VIII nerve acoustic input in one, and lateral line mechanoreceptive and electroreceptive input in the other. Electrophysiological recording and mapping experiments demonstrate a medial auditory region, a lateral electroreceptive region, and an intercalated mechanoreceptive region in the TS. Nissl and Golgi‐Cox preparations distinguish two rostrocaudally elongate, nuclear divisions, which correlate, one with the auditory and the other with the mechano‐ and electroreceptive regions.

The medially positioned auditory nucleus is here called the nucleus centralis. The nucleus centralis appears as a rostrally flattened cylinder of uniformly packed cells, covered dorsally and laterally by a fiber rind. Cells within this nucleus conform to one of three general cell types based upon somatic and dendritic morphology: type 1 cells, which are the most abundant, have a single major primary dendrite and an axon typically arising from the same somatic pole; type 2 cells have two major primary dendrites and an axon, which issues from a third distinct somatic pole; and type 3 cells have several major primary dendrites and their axons are associated with one of the major somatic poles. No systematic orientation of dendrites could be found in the nucleus centralis.

The laterally positioned lateral line nucleus, to be called the nucleus lateralis, includes two subdivisions: a large pars lateralis containing predominantly electroreceptive units, and a smaller, ventromedial pars medialis encompassing predominantly mechanoreceptive units. Each subdivision is found to be somatotopically organized, inputs from the head projecting to rostral areas and inputs from the tail to caudal areas. Although the cell types resemble those described for the nucleus centralis, a greater degree of cytoarchitectural orderliness is discernible: (a) cells in the nucleus lateralis group into four, alternating cell‐poor cell‐rich, layers; and (b) the dendritic fields of many type 1 and type 2 cells located in layer II tend to orient in a rostrodorsalcaudoventral attitude, perpendicular to the laminar planes.

Fink‐Heimer preparations of brains with unilateral, lateral line lobe lesions demonstrate heavy fiber and terminal degeneration confined to the nucleus lateralis on both sides. Lateral line fibers ascend bilaterally in the lateral halves of the lateral lemnisci. At the level of the dorsal oculomotor nucleus the lemniscal fibers in this portion split into two fascicles, one proceeding rostrally to innervate the rostral portion of the nucleus lateralis, and the other arching back dorsolaterally to innervate the caudal portions of the nucleus.
The second somatic sensory area (smII) of opossum neocortex
Authors: Pubols Benjamin H.
Published: December 2004

Organization of the neocortical second somatic sensory area (SmII) of anesthetized Virginia opossums has been examined utilizing microelectrode recording techniques. SmII is situated between the first somatic sensory area (SmI) medially, and the rhinal fissure laterally. The head representation is located anteromedially within SmII, and the hindlimb representation posterolaterally, with the forelimb representation in between. Approximately 49% of SmII is devoted to representation of the head, 36% to forelimb representation, and 15% to trunk and hindlimb representation. All peripheral receptive fields (RF's) were either contralateral or bilateral. Approximately 63% of head RF's, 25% of forelimb RF's and 100% of hindlimb RF's were bilateral. For a given body locus, SmII RF's are larger than those for SmI. SmII is contained entirely within an area yielding evoked potentials responses to auditory click stimuli.
Visual discriminations of cats with cortical and tectal lesions
Authors: Loop Michael S. , Sherman S. Murray
Published: December 2004

Fourteen cats were trained on three visual discrimination tasks: light vs. dark, horizontal vs. vertical stripes, and upright vs. inverted triangles. Four of the cats then underwent large, bilateral occipito‐temporal cortex ablations; postoperatively, they demonstrated little or no visually guided orienting behavior and could solve only the brightness task and not the preoperatively learned pattern discriminations. Six other cats underwent the same cortical ablations plus a transection of the commissure of the superior colliculus; postoperatively, they demonstrated good visually guided orienting behavior (i.e., the Sprague effect) but still could solve only the brightness task. The final four cats were controls and underwent no surgery; they demonstrated good retention of the pattern task despite an extensive idle period corresponding to the postoperative period before retesting in the above ten cats. These data indicate that, while a transection of the collicular commissure after visual decortication dramatically improves visual orienting, it does not obviously improve visual discrimination abilities.
The lateral reticular nucleus of the opossum (Didelphis virginiana). II. Connections
Authors: Martin George F. , Andrezik J. , Crutcher K. , Linauts M. , Panneton M.
Published: December 2004

Conformational, histochemical and histofluorescent studies reveal that the entire lateral reticular nucleus (LRN) of the Virginia opossum is positive for cholinesterase activity and that its rostral portion is rich in fluorescent varicosities of the catecholamine type. Although neocortical‐LRN connections are relatively meagre, projections to the LRN from the red nucleus are extensive and topographically organized. Rubral‐LRN fibers arise from large‐medium sized neurons and distribute to the trigeminal division of the LRN as well as to specific portions of its external and internal divisions. Certain areas of the midbrain and pontine reticular formation, as well as the vestibular nuclei, project to the LRN and there is some evidence that reticular neurons adjacent to the LRN provide additional input. Although a relatively small fastigial‐LRN projection exists, no evidence was found for a contribution from any of the other deep cerebellar nuclei. Spinal‐LRN connections are extensive and topographically organized. Each of the inputs to the LRN have specific terminal targets, but there are varying degrees of overlap.

Most of the LRN projects in an organized fashion to the anterior lobe of the spinal cerebellum, whereas only relatively restricted areas relay to the paramedian lobule and the pyramis. Lateral reticular axons distribute to specific longitudinal zones in such areas and the available material suggests that both convergence and divergence exist. The LRN also relays to the lobus simplex, and perhaps to crus I, as well as to visual‐auditory areas of the cerebellar vermis. The distribution of the various afferent connections of the LRN is interpreted in light of LRN‐cerebellar connections. Although we have described details that have not been elucidated in other species, where comparisons can be made it appears that the connectivity of the opossum LRN is comparable in most respects to that of placental mammals.
Retinal projections in the native cat, Dasyurus viverrinus
Authors: Sanderson K. J. , Pearson Lyn J.
Published: December 2004

Retinal projections were examined in the native cat, Dasyurus viverrinus using Fink‐Heimer material and autoradiography. We found six regions in the brain which receive retinal projections. These are (1) the dorsal lateral geniculate nucleus (2) the ventral lateral geniculate nucleus (3) the lateral posterior nucleus (4) the pretectum (5) the superior colliculus, and (6) the accessory optic system. We did not examine the hypothalamus. The accessory optic system and the lateral posterior nucleus receive a contralateral retinal projection only and the other four regions receive a bilateral retinal projection.

There is extensive binocular overlap in the dorsal lateral geniculate nucleus. On the side contralateral to an eye injection of 3H leucine our autoradiographs show four contralateral layers which fill most of the nucleus. Three of these layers, 3, 4 and 5, also receive input from the ipsilateral eye. Layer 1 which lies adjacent to the optic tract receives only contralateral retinal input. Layer 2 receives a direct retinal input only from the ipsilateral eye. The ipsilateral projection to the dorsal lateral geniculate nucleus forms a fairly continuous patch which is not divided into separate layers. The ipsilateral retinal input is located in the dorsal part of the lateral geniculate nucleus. The ventral quarter of the nucleus only receives a contralateral retinal input and therefore represents the monocular part of the visual field.
Horizontal cells of the turtle retina. II. Analysis of interconnections between photoreceptor cells and horizontal cells by light microscopy
Authors: Leeper Harold F.
Published: December 2004

Criteria were established whereby the chief and accessory members of double cones, red‐, green‐, and blue‐sensitive single cones, and rods could be distringuished form one another in 1‐μm sections through the retinas of Pseudemys scripta elegans and Chelydra serpentina. Criteria included the presence or absence of an oil droplet, the size, color, and radial position of the oil droplet, the size and shape of the inner and outer segments, and the shape and orientation of the connection between the perikaryon and synaptic terminal of each receptor cell.

Using these criteria, the color‐specific interconnections between horizontal cells and receptor cells were analyzed using 1‐μm serial sections through Golgistained examples of horizontal cells of each type. The results of this analysis area:

H1 cell bodies contact both the red‐ and green‐sensitive members of double cones, as well as red‐ green‐sensitive single cones.

H1 aoxn terminals contact only the red‐sensitive chief members of doulbe cones, red‐sensitive single cones, and rods.

H2‐type cells contact only green‐ and blue senstive single cones.

H2‐type cells contact only blue‐sensitive single cones.

H2‐type cells contact only green‐sensitive accessory members of double cones.

With the exception of H1 cell bodies, all horizontal cells generally contacted every apporpriate receptor cell type within their receptive field. A model for the generation of complex horizontal cell light responses is proposed and discussed.
Postnatal changes in the number of astrocytes, oligodendrocytes, and microglia in the visual cortex (area 17) of the macaque monkey: A stereological analysis in normal and monocularly deprived animals
Authors: O'Kusky John , Colonnier Marc
Published: December 2004

The numerical densities (Nv) of astrocytes, oligodendrocytes, and microglia were measured in indvidual laminae of the striate cortex of macaque monkeys ranging in age from newborn to adult. Using measurements of cortical thickness and surface area, the total number of cells in the striate cortex of one hemisphere was derived for each glial cell type. Normal monkeys were compared at 3 months and 6 months of age to animals reared from birth with a monocular eyelid suture. No significant differences were observed between normal and monocularly deprived monkeys. The combined data from these groups, however, demonstrated several significant developmental changes. The Nv of astrocytes decreased from birth to 6 months of age and susequently increased in the adult. The greatest changes were seen in the more superficial laminae. These changes, however, were only a response to a substantial overshoot in cortical volume at six months: the total number of astrocytes in the striate cortex did not change. There was a tenfold increase in both the Nv and the total number of oligodendrocytes from birth to maturity with a corresponding increase in the density of myelinated axons. The greatest changes were observed in the deeper laminae. The total number of microglia remained relatively constant from birth to 6 months of age. There was a 55% reduction in the number of microglia in the adult, although statistical analysis indicated that this decrease was only of borderline significance. The possible relationships between these postnatal changes in glial cell numbers and the development of neuronal connectivity are discussed.
Electrophysiologic studies of cutaneous nerves of the forelimb of the cat
Authors: Kitchell R. L. , Canton D. D. , Johnson R. D. , Maxwell S. A.
Published: December 2004

The cutaneous innervation of the fo relimb was investigated in 20 bar‐biturate‐anesthetized cats by using electrophysiological techniques. The cutaneous area (CA) innervated by each cutaneous nerve was delineated in at least six cats by brushing the hair in the CA with a small watercolor brush while recording from the nerve. Mapping of adjacent CA revealed larger overlap zones (OZ) than were noted in the dog. Remarkable findings were that the brachiocephalic nerve arose from the axillary nerve and the CA comparable to that supplied by the cutaneous branch of the brachiocephalic nerve in the dog was supplied by a cutaneus branch of the suprascapular nerve. The CA supplied by the communicating branch from the musculocutaneous to the median nerve was similar in both species except that the communicating branch arose proximal to any other branches of the musculocutaneous nerve in the cat, whereas it was a terminal branch in the dog. The superficial branch of the radial nerve gave off cutaneous brachial branches in the cat proximal to the lateral cutaneous antebrachial nerve. The CA of the palmar branches of the ulnar nerve did not completely overlap the CA of the palmar branches of the median nerve as occurred in the dog; thus an autonomous zone (AZ) for the CA of the palmer branches of the median nerve is present in the cat, whereas no AZ existed for the CA of this nerve in the dog.
A quantitative study of the thalamocortical and other synapses in layer IV of pyramidal cells projecting from mouse SmI cortex to the caudate‐putamen nucleus
Authors: Hersch Steven M. , White Edward L.
Published: December 2004

The thalamocortical and other synapses of the apical dendrites of corticostriatal projection neurons in mouse primary somatosensory cortex (SmI) were examined by combining anterograde degeneration with the retrograde transport of horseradish peroxidase (HRP). Electrolytic lesions were made in the ventrobasal thalamus, followed 3 days later by injections of 40% HRP into the ipsilateral caudate‐putamen nucleus. The next day, the mice were perfused and the SmI cortex ipsilateral to the lesion and injection sites was chopped at 125‐μm and reacted for HRP using a CoCl2‐DAB method. HRP‐labeled corticostriatal cells in SmI cortex were medium‐sized pyramidal cells, having somata located in the superficial portion of layer V and apical dendrites extending into layer I. Seven corticostriatal cells were serially thin sectioned and the layer IV portions of their apical dendrites were reconstructed. Each apical dendrite formed only one or two thalamocortical synapses (0.3 to 0.9% of their synapses in layer IV) indicating that corticostriatal neurons may be minimally responsive to direct synaptic input from the specific thalamic nuclei. Each apical dendrite formed about 12.6 asymmetrical synapses for every symmetrical synapse, suggesting that the relative numbers of excitatory and inhibitory synapses impinging on apical dendrites belonging to an individual class of neurons may be specified.
Fetal development of primate chemosensory corpuscles. I. Synaptic relationships in late gestation
Authors: Zahm Daniel S. , Munger Bryce L.
Published: December 2004

Fetal macaque chemosensory corpuscles during the last part of gestation contained chemosensory, sustentacular, and undifferentiated basal cells. Sustentacular cells had apical secretory granules and no specialized contacts with axons. Chemosensory cells contained basal collections of 80–100 nm dense core granules, and specialized axonal contacts of three types—afferent synapses, efferent synapses, and subsurface cisternae. Afferent synapses were commonly present on electron opaque cells with many 80–100‐nm granules, typical 40–60‐nm synaptic vesicles, and a few cisternae of smooth or granular endoplasmic reticulum. Cells with subsurface cisternae and/or efferent synapses were usually electron lucent, lacked vesicles and granules, and contained numerous intracytoplasmic cisternal elements. A continuum of intermediate forms was observed. It is postulated that transition of synaptic arrays accompanies the maturation of individual chemosensory cells.
The organization of two cutaneous submodalities in the forearm region of area 3b of cat somatosensory cortex
Authors: Sretavan David , Dykes Robert W.
Published: December 2004

Electrophysiological data were collected from the forelimb region of somatosensory cortex in barbiturate‐anesthetized cats using low‐impedance microelectrodes in both perpendicular and nearly horizontal penetrations. The data within cytoarchitectonic area 3b were classified according to receptive field locus and submodality. The forearm cortex was shown to consist of segregated regions of slowly adapting and rapidly adapting neurons arranged in a pattern unique to each animal. The general organization of each submodality consisted of interdigitating bands of submodality‐specific neurons. Horizontal penetrations confirmed data obtained from vertical penetrations.

The somatotopic representation within the forearm region was arranged in a way that was complementary to the submodality segregation. Each part of the forearm appeared to be represented by both the slowly adapting and rapidly adapting neurons so that area 3b contained two complete maps of the forearm. Yet, the slowly and rapidly adapting maps were organized so that the same body part was found in only one part of the cortex; the slowly and rapidly adapting regions, for each body part tended to be adjacent to one another. Area 1 was incompletely sampled; however, there appeared to be a separate representation of the cutaneous surface located there.
Electron microscopic studies of serially sectioned cat spinal α‐motoneurons: V. motoneurons innervating fast‐twitch (type FF) units of the gastrocnemius muscle
Authors: Kellerth J.‐O. , Conradi S. , Berthold C.‐H.
Published: December 2004

Two intracellularly stained gastrocnemius a‐motoneurons of the FF‐type (Burke et al., ′73) were studied ultrastructurally. The architecture and synaptology of the cell bodies and proximal dendrites were analyzed from long series of consecutive sections according to, a methgd previously described (Conradi et al., ′79a). Several of the dendrites had a base diameter exceeding 10 μm. The proportion of the cell surface area covered by boutons was 40‐50% for the soma and about 70% for the proximal dendrites. In both regions, about 20‐25% of the boutons were of the S‐type and 60‐70% of the F‐type. In general, the type FF α‐motoneurons exhibited the same gross synaptological characteristics as those found earlier in type FR α‐motoneurons (Kellerth et al., ′79), although the large boutons of the C‐type were more frequent on the proximal dendrites and axon hillocks of the present cells. M‐boutons of dorsal root origin were found on several of the proximal dendrites. The observed regional differences in the spectrum of boutons on the motoneuron surface seem to follow gradients operating in the somato‐fugal direction, and they are apparently independent of the size or direction of the neuronal processes.
Astrocytes in the nonmyelinated lamina cribrosa of the rat are less polarized than in the optic nerve proper: A freeze‐fracture study
Authors: Bäuerle Carin , Wolburg Hartwig
Published: December 2004

Astrocytes in the lamina cribrosa of the adult rat optic nerve which is devoid of myelination were investigated by means of quantitative freeze‐fracturing. The orthogonal arrays of particles (OAPs) were found to be less concentrated in the membranes of subpial endfeet when compared to the OAP concentration in endfeet of the optic nerve proper. This result corresponds to that found previously in the myelin deficient rat (Rohlmann et al: Glia 5:259, 1992) suggesting that lack of myelination generally correlates with altered astrocytes. © 1993 Wiley‐Liss, Inc.
Differential intracellular compartmentalization of phosphotyrosine phosphatases in a glial cell line: TC‐PTP versus PTP‐1B
Authors: Faure Robert , Posner Barry I.
Published: December 2004

Intracellular levels of protein‐phosphotyrosine are regulated by the protein‐tyrosine phosphatase (PTP) family. Cellular compartmentalization may play an important role in modulating the function of these enzymes. The recent demonstration that PTP‐1B is localized to the endoplasmic reticulum (Frangioni et al: Cell 68:545, 1992) is consistent with this proposition. In this study we have examined the intracellular distribution of TC‐PTP in a glial cell line (C6). Using indirect immunofluorescence we have shown that this enzyme is distributed differently from PTP‐1B and is mainly concentrated in the perinuclear region of these cells. © 1993 Wiley‐Liss, Inc.
Histamine and prostanoid receptors on glial cells
Authors: Inagaki Naoyuki , Wada Hiroshi
Published: December 2004

Glial cells in vitro express at least two types (H1 and H2) of histamine receptors and three types (EP, FP, and TP) of prostanoid receptors. The receptors expressed by glial cells differ according to the cell type and source in the brain. Further‐more primary astrocytes of same type derived from the same brain region are composed of heterogeneous subpopulations expressing different subsets of receptors. Fura‐2 based Ca2+ microscopy revealed that astrocyte processes are important sites for histamine‐induced Ca2+ signalling. Histamine and prostanoid receptors on glial cells may play important roles in the actions of histamine and prostanoids in the central nervous system. © 1994 Wiley‐Liss, Inc.
Sarverogenin, vermutliche Struktur. Glykoside und Aglykone, 314. Mitteilung
Authors: Fuhrer H. , Zürcher R. F. , Reichstein T.
Published: December 2004

Sarverogenin is most probably a 3β, 11β, 14β‐trihydroxy‐7, 8β‐epoxy‐12‐oxo‐5β‐card‐(20:22)‐enolide (3). This follows from IR., NMR., and mass spectra together with former chemical results.
Der FISCHER'sche Indolringschluss mit 1, 3‐disubstituierten 4‐Piperidonen. 7. Mitteilung über synthetische Indolverbindungen [1]
Authors: Ebnöther A. , Niklaus P. , Süess R.
Published: December 2004

Treatment of the arylhydrazones of 1, 3‐disubstituted 4‐piperidones with ethanolic hydrogen chloride (FISCHER reaction conditions) affords 1, 2, 3, 4‐tetrahydropyrimido [3, 4‐a]‐indoles in good yields. During catalytic hydrogenation in the presence of protons these tetrahydropyrimido‐indoles are split into 2‐(2‐methylamino‐ethyl)‐indoles. The formation of these tricyclic products can be explained by rearrangement immediately following the normal FISCHER reaction. If the substituent at the piperidine nitrogen is an acyl group, normal or rearranged products are formed, depending on the nature of the 3‐substituent.
Isolierung von (−)‐R‐4‐Hydroxy‐pyrrolidon‐(2) und einigen weiteren Verbindungen aus Amanita muscaria. 31. Mitteilung über Inhaltsstoffe von Fliegenpilzen
Authors: Matsumoto T. , Trueb W. , Gwinner R. , Eugster C. H.
Published: December 2004

Aus Carpophoren von Amanita muscaria (L.′ ex Fr.) HOOKER wurden neu β‐n‐Butyl‐D‐glucopyranosid, (−)‐R‐4‐Hydroxy‐pyrrolidon‐(2), Uracil, Hypoxanthin und (−)‐1,2,3,4‐Tetrahydro‐1‐methyl‐β‐carbolin‐3‐carbonsäure isoliert.
Beitrag zur Charakterisierung der Lipide aus den Linsen einiger Säugtiere
Authors: Bernhard Karl , Lesch Peter , Greub Hans‐Rudolf
Published: December 2004

Total lipids from the lenses of pigs, calves, cattle and fin whales have been separated into different fractions. Their lipid content seems to be the lowest of all organs. The predominant lipid classes are cholesterol, ethanolamine cephalines, and sphingomyelines. The analysis of the fatty acids after saponification showed differences in the main components depending on the source of the material. In all cases 5–7% hydrocarbons were found which are probably of alimentary origin and are deposited in the lens.
Induktive und sterische Effekte bei der BECKMANN‐CHAPMAN‐Umlagerung von Alkyl‐ketoxim‐pikryläthern
Authors: Fischer H. P. , Funk‐Kretschmar F.
Published: December 2004

The rates of the BECKMANN‐CHAPMAN rearrangement of the ketoximpicryl‐ethers 1a–1k in 1, 4‐dichlorobutane are correlated with parameters describing the bulk of the substituted groups R and R′. From regression analyses it is concluded that the relative rate constants are mainly controlled by steric contributions in the ground state, such as geminal interactions of R with R′ and vicinal interactions of R′ with OX, and less by inductive effects.

Conformational equilibria between (Z)‐ and (E)‐isomers of N‐alkyl‐N‐picryl‐amids have been studied by NMR. in several solvents.
Partialsynthese von 4′‐Demethylepipodophyllotoxin. 22. Mitteilung über mitosehemmende Naturstoffe [1]
Authors: Kuhn M. , Keller‐Juslén C. , von Wartburg A.
Published: December 2004

4′‐Demethylepipodophyllotoxin (III) has been synthesized by epimerisation of 4′‐demethylpodophyllotoxin (I) via the corresponding chloride II. An improved method for the preparation of III has been developed by selective ether cleavage of the easily available podophyllotoxin (V) using the bromoderivatives VI and VII as intermediates.
Viminolon, Strukturbeweis. Glykoside und Aglykone, 315. Mitteilung
Authors: Stöckel K. , Hürzeler H. , Reichstein T.
Published: December 2004

Reduction of di‐O‐benzoyl‐viminolon (1) with LiAlH4 gave a mixture of 17‐isopregn‐5‐ene‐heptols. Treatment of this mixture with NaIO4 produced the amorphous 12‐O‐formyl sarcostinketone (= 12‐O‐formyl‐3β, 8β, 12β, 14β‐tetrahydroxy androst‐5‐en‐20‐one) (4). This together with former results proves the structure of 1.
Über neue Bufadienolide aus Ch'an Su. Über Krötengifte, 34. Mitteilung
Authors: Höriger Niklaus , Linde Horst H. A. , Meyer Kuno
Published: December 2004

Two new bufadienolides, isolated from Ch'an Su, are proved to be 19‐oxo‐cinobufagin (III) and 19‐oxo‐cinobufotalin (V), respectively.
Über die absolute Konfiguration der Visnagane
Authors: Bernotat‐Wulf Hannelore , Niggli A. , Ulrich L. , Schmid H.
Published: December 2004

(+)‐cis‐Khellactone methyl ether (4) and (−)‐trans‐khellactone methyl ether (6) had earlier been assigned the absolute configurations 3′‐S; 4′‐S and 3′‐S; 4′‐R, respectively, on the basis of the FREUDENBERG, rule. Both compounds together with their defunctionalised derivatives (−)‐7 and (+)‐8 (=(+)‐lomatin), obtained from a mixture of (+)‐visnadin (1) and (+)‐samidin (2), were investigated by the HOREAU method. A conformational analytical study showed that the optical yield should rise in the order 4 < 6 < 7, 8. This order was found and the α‐phenylbutyric acid liberated was always dextrorotatory. The centre 3′ of the khellactones and their derivatives must be R‐chiral and not S. Treatment of (−)‐6 with pyridinium perbromide gave (−)‐trans‐3‐bromokhellactone methyl ether (11) as orthorhombic crystals. The X‐ray crystal structure determination was made using the anomalous scattering of the Mo‐K α radiation by Br. The result, — centre 3′ R‐chiral (fig. g) — showed that the HOREAU method was correct.
Löslichkeiten und Aktivitätskoeffizienten von H2S in Elektrolytmischungen
Authors: Gamsjäger H. , Schindler P.
Published: December 2004

From solubility measurements on hydrogen sulfide in aqueous solutions of the composition [H+] = HM, [Na+] = (I — H) M = A M, [Cl−] = I M at 25°C, the molar and molal activity coefficients of H2S have been calculated. The activity coefficients of H2S in the electrolyte mixtures have been found to be additive functions of the activity coefficients in the individual electrolyte solutions at the same ionic strength. This result is predicted by the internal pressure theory of salt effects on non‐electrolyte activity coefficients, provided that the volume change upon mixing two electrolyte solutions of the same ionic strength is zero.
Synthese von 1, 2‐Dimethyl‐phenanthro[1,2‐b]furan und 1‐Äthyl‐2‐methyl‐phenanthro[1,2‐b]furan. Furanabkömmlinge, 26. Mitteilung
Authors: Stöckel K. , Stöcklin W. , Reichstein T.
Published: December 2004

We describe here the synthesis of 1,2‐dimethyl‐phenanthro [1,2‐b] furan (11) and 1‐ethyl‐2‐methyl‐phenanthro [1,2‐b] furan (13). The starting material was the known ethyl 2‐methyl‐phenanthro [1,2‐b] furan‐1‐carboxylate (4). The two synthetized substances were characterized by their UV.‐, IR.‐, NMR.‐ and mass spectra, and identified with two products obtained by selenium dehydrogenation of anhydrohirundigenin.
Die Synthese der Alkaloide der Ergotoxin‐Gruppe. 70. Mitteilung über Mutterkornalkaloide [1]
Authors: Stadler P. A. , Guttmann St. , Hauth H. , Huguenin R. L. , Sandrin Ed. , Wersin G. , Willems H. , Hofmann A.
Published: December 2004

The syntheses of the alkaloids of the ergotoxine‐group i.e. ergocristine, α‐ and β‐ergokryptine, and ergocornine, are described. Using starting material with known stereochemistry these syntheses allowed to determine the absolute configurations also at C‐2′ and C‐12′ in the peptide part, which could not be derived from analytical data. All ergot alkaloids of the peptide type possess the same stereochemical structure.
Mikrobiologische Umwandlung von bicyclischen Monoterpenen durch Absidia orchidis (VUILL.) HAGEM. 2. Teil. Hydroxylierung von Fenchon und Isofenchon. 18. Mitteilung über Reaktionen mit Mikroorganismen [1]
Authors: Pfrunder B. , Tamm Ch.
Published: December 2004

(+)‐Fenchone (3a) was transformed to 6‐exo‐hydroxy‐fenchone (6β‐hydroxy‐1, 3, 3‐trimethyl‐nor‐bornan‐2‐one) (1a) and to 5‐exo‐hydroxy‐fenchone 5β‐hydroxy‐1, 3, 3‐trimethyl‐nor‐bornan‐2‐one (4a) by the mycelium of Absidia orchidis (Vuill.) Hagem. The structure of the two products was proven by a detailed analysis of the NMR. spectra of the corresponding acetyl derivatives 2a and 5a respectively, and by CrO3‐oxidation. 1a yielded the β‐diketone 6a, and 4a the diketone 8a. Whereas 8a was stable to alkali 6a was cleaved to the cyclopentane carboxylic acids 7 and 9. — Incubation of (—)‐fenchone (3b) yielded the enantiomeric hydroxylation products 1b and 4b in the same ratio. ‐ (—)‐Isofenchone (11a) was transformed by Absidia orchidis into the two epimers 6‐endo‐hydroxy‐isofenchone (6β‐hydroxy‐1, 5, 5‐trimethyl‐nor‐bornan‐2‐one) (12a) and 6‐exo‐hydroxy‐isofenchone (6β‐hydroxy‐1, 5, 5‐trimethyl‐nor‐bornan‐2‐one) (10a.) CrO3‐oxidation of both 10a and 12a gave the same β‐diketone 6a. ‐ (+)‐Isofenchone gave the corresponding enantiomeric hydroxy derivatives 10b and 12b on incubation with Absidia orchidis.
Photoelektronspektroskopische Bestimmung der Wechselwirkung zwischen nicht‐konjugierten Doppelbindungen [1]. Vorläufige Mitteilung
Authors: Bischof P. , Hashmall J. A. , Heilbronner E. , Hornung V.
Published: December 2004

The interaction between the two non‐conjugated π‐bonds in 1, 4‐cyclohexadiene, norbornadiene and bicyclo[2.2.2]octadiene has been determined by photoelectron spectroscopy to be 1.0, 0.85 and 0.6 eV respectively.
Bemerkungen zum Metallmonoschichtmodell der Kationenadsorption
Authors: Schmidt E.
Published: December 2004

Die Anwendung des thermodynamischen Formalismus ideal polarisierbarer Elektroden auf das Metallmonoschicht‐Adsorbat zeigt, dass der übliche, einer Nernst‐Gleichung analoge Ansatz für den Zusammenhang zwischen Potential und Oberflächenkonzentration bestimmte Ladungsstöchiometrie‐Eigenschaften des Adsorbats impliziert, und zwar verhält sich das adsorbierte Kation Me2+ so, als werde es beim Eintritt in die Interphase zur Neutralspezies Me0 entladen. Die Oberflächenladung ist dementsprechend eine lineare Funktion der Oberflächenkonzentration. Die Ladungssumme von diffuser Doppelschicht und allfälligen spezifischen Anionenadsorbaten ist eine reine Potentialfunktion.

Das Metallmonoschichtkonzept ist ein Näherungsmodell eines Kationenadsorbats, dessen Realisierbarkeit in einfachen Fällen anhand austrittselektrischer Kriterien beurteilt werden kann.
Struktur und Mechanismus bei Fragmentierungsreaktionen 1. Teil. Die stereoisomeren 10‐Chlor‐decahydro‐isochinoline. Fragmentierungsreaktionen, 23. Mitteilung
Authors: Geisel M. , Grob C. A. , Wohl R. A.
Published: December 2004

cis‐10‐Chloro‐N‐methyl‐decahydro‐isoquinoline (5) and its trans‐isomer 6 undergo heterolytic fragmentation in 80% ethanol by different mechanisms. As predictable on stereo‐chemical grounds the cis‐isomer 5 reacts by the accelerated synchronous mechanism, the trans‐isomer 6, however, by the two‐step carbonium ion mechanism. Synchronous fragmentation therefore dominates over the two‐step process even when the latter would lead to a relatively stable tertiary carbonium ion. In both cases the more highly substituted and thermochemically more stable olefinic fragment 8 is formed.
Rapid Instrumental Nuclear Activation Analysis of Rocks, Cements and Meteorites
Authors: Wyttenbach A.
Published: December 2004

The experimental set‐up and the method for γ‐spectrum analysis as used in the activation analysis of rocks, cements and meteorites by reactor neutrons are discussed. Rapid nondestructive simultareous determination of several elements is possible. Fractional percent reproducibility is possible for Al, Na and Mn; the determination of Ca, Mg and V in the samples studied us influenced by the Al‐ and Mn‐content, but reproducibility approaches 1% in favorable cases. Accuracy is generally within the limits set by the reproducibility. The minimum weight of the sample is small (10–40 mg), but the grain‐size must be below 150 mesh; in the case of meteorites, a grain‐size effect has been demonstrated. Representative results for several standard rocks and cements, for 7 L‐chondrites, 2 hyperstene achondrites and separate mineral phases of the Elenovka chondrite are given.