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C J Wilson

Publications and source records attributed to C J Wilson.

At least 127 records · Page 7Linked to original sources
PubMed1980

Fine structure of rat locus coeruleus.

Locus coeruleus of the rat was studied in material prepared by aldehyde-osmium fixation. Cell bodies of locus coeruleus neurons possess large nuclei with a prominent nucleolus, a homogeneous karyoplasm of moderate density, and occasional indentations of the nuclear membrane. The cytoplasm is rich in organelles, including an extensive network of endoplasmic reticulum which forms well organized Nissl bodies. The highly developed Golgi apparatus surrounds the nucleus and extends into large dendritic trunks. In coronal section, cell bodies appear elongated along an approximate dorso-ventral axis, and most dendrites as well as axons appear in cross-section. In parasagittal sections the cells are very elongate, with dendrites and axons in the neuropil mostly cut longitudinally. Thus, locus coeruleus neurons possess disc-shaped dendritic fields parallel to the anterior-posterior axis of the brainstem, with predominantly longitudinal axo-dendritic synaptic configurations. Presynaptic profiles in locus coeruleus neuropil were classified according to the characteristics of their vesicle populations and other features. The most frequently encountered synaptic ending was characterized by small, round, densely packed synaptic vesicles, and comprised approximately 41% of the total sample of 775 synapses. Another group having large, rounded synaptic vesicles, which could be traced in a number of instances to large myelinated axons, accounted for 20% of the sample. Synaptic endings having large, flattened vesicles were also numerous, comprising 23% of the total. Another category of presynaptic endings was identified as those possessing numerous, small, flattened vesicles and comprising about 11% of the sample. Presynaptic endings having many vesicles of mixed sizes accounted for 2% of the total, and another group of the same proportion having small, rounded synaptic vesicles but also an unusually large number of larger, dense-cored vesicles was also present. Two other categories of synaptic endings were encountered, each comprising less than 1% of the total. One of these was derived from small, unmyelinated axons and contained clusters of pleomorphic synaptic vesicles. The other consisted of dendro-dendritic synapses between locus coeruleus neurons and also displayed small clusters of pleomorphic synaptic vesicles near the zone of synaptic apposition. Quantitative analysis revealed that most afferents to the nucleus synapse onto dendrites ranging between 0.5 and 2.5 micrometers in diameter and onto spine-like appendages derived from somata and dendrites. There were no significant differences between different categories of afferent terminals and their spatial distribution onto various postsynaptic targets of locus coeruleus neurons.

Animals↗
PubMed1980

Monoaminergic presynaptic axons and dendrites in rat locus coeruleus seen in reconstructions of serial sections.

Locus coeruleus was studied in rats pretreated with intraventricularly administered 5-hydroxydopamine 1/2 to 3 hours prior to conventional aldehydeosmium fixation. Presynaptic profiles in locus coeruleus neuropil were classified according to the characteristics of their vesicle populations and other features, as in our previous report. Similar categories of endings were observed, and the sites of postsynaptic innervation were identical to those described previously, that is, a majority of synapses were made with dendrites between 0.5 and 2.5 micrometers in cross-sectional diameter, a significant proportion was seen ending onto somatic and dendritic spines, with a relative paucity of synapses made with spine-free membrane of somata and large dendritic trunks. There were no significant differences between different morphological categories of afferent terminals and their spatial distribution onto various postsynaptic targets on locus coeruleus neurons. In addition to various membrane-bound compartments of the cytoplasm, three categories of synaptic endings were labelled by the synaptic marker, while all others were unlabelled. One of these was identified previously as containing small, rounded synaptic vesicles and an unusually large number of large, dense core vesicles. The synaptic vesicles were lightly labelled with scattered, small, eccentrically placed opaque cores inside the synaptic vesicles, apparently randomly distributed throughout the terminal. This terminal is thought to be serotonergic. A second category of labelled synapse has been previously identified as that derived from small, unmyelinated axons having clusters of pleomorphic synaptic vesicles in which the vesicles are heavily labelled by 5-hydroxydopamine. These are believed to represent catecholaminergic synaptic endings derived from recurrent collaterals as well as extrinsic catecholaminergic innervation of locus coeruleus. A final category of heavily labelled profile was identified as presynaptic dendrites, which, along with recurrent catecholaminergic axon collaterals, probably play an important part in the intrinsic regulation of nucleus locus coeruleus. When 59 labelled synapses were examined in adjacent serial sections, every vesicle-containing profile was associated with a synaptic contact having characteristic membrane specializations. A similar result was obtained when 132 other unlabelled terminals of different categories were examined in serial sections.

Animals↗
PubMed1979

Fascia lata urethrovesical suspension for recurrent stress urinary incontinence.

Although the physiologic mechanisms of normal micturition in the female subject are not fully understood, it is generally believed that urinary continence is maintained by a competent urethrovesical neck. Unfortunately, the patient who has had multiple operations for recurrent stress urinary incontinence often has a urethra that is shortened and fixed in scar tissue. In such patients, anterior colporrhaphy with operative release of the periurethral fibrosis and plication of the endopelvic fascia to create a functionally more normal urethrovesical junction will increase the chances for good results. A fascia lata support of the proximal 1 to 2 cm of the urethra ensures continued elevation of the urethra and with stress the sling provides a pulling-up effect. Fifty patients with a suburethral sling procedure are presented in detail. Forty-seven of these patients had a total of 121 prior operative procedures for stress urinary incontinence. Urologic studies are outlined. Forty-two patients (84%) were continent postoperatively, five were improved, and three had failures. Operative technique and complications are discussed.

Adult↗
PubMed1979

A simple and rapid section embedding technique for sequential light and electron microscopic examination of individually stained central neurons.

A method for section embedding of central nervous tissue, and its application to light and electron microscopic examination of neurons stained by intracellular injection of horseradish peroxidase, is described. After primary fixation in aldehydes, thick (10--80 micrometer) sections are cut on a Vibratome. They are then treated for the histochemical demonstration of peroxidase, postfixed in osmium tetroxide, dehydrated and infiltrated with Spurr's low viscosity resin. Infiltrated sections are embedded between glass slides and coverslips coated with a transparent layer of teflon and polymerized. The resulting mount allows protracted storage and high resolution light microscopic examination of sections. When desired, the glass components can be removed and the specimen cemented to a blank block for thin sectioning and electron microscopic examination.

Animals↗
PubMed1979

Sites of action of amphetamine intrinsic to catecholaminergic nuclei: catecholaminergic presynaptic dendrites and axons.

1. It is now well established that the behavioral actions of amphetamine, especially locomotor and stereotyped behaviors, are dependent in part upon the release of catecholamines in the central nervous system. 2. A variety of empirical evidence has established that the release of catecholamines by amphetamine leads to changes in neuronal activity in regions postsynaptic to catecholaminergic nerve terminals. In addition, release of catecholamines is accompanied by a marked inhibition of neuronal firing in catecholaminergic neurons. 3. At least two conceptions have been advanced to account for this marked decrease in catecholaminergic neuronal activity. (a) In one of these, release of catecholamines from presynaptic terminals is thought to lead to a compensatory decrease in neuronal firing rate by means of a postsynaptic neuronal feedback loop from regions innervated by catecholaminergic neurons. (b) In the other, decreased neuronal activity is hypothesized to result from local release of catecholamines onto or near catecholaminergic neuronal dendrites and somata, a phenomenon that has been characterized as self-inhibition. 4. For dopaminergic neurons, recent biochemical, neuropharmacological and neuroanatomical evidence suggests that the latter process could be subserved by dopamine released from dopaminergic neuronal dendrites, i.e., "presynaptic" dendrites.

Amphetamine↗
PubMed1979

Ready-to-eat cereals and dental caries in children: a three-year study.

In a three-year study of 145 adolescent males in a boarding school in Wisconsin, there were no statistically significant differences in dental caries experience between a group consuming phosphates added to pre-sweetened and non-presweetened ready-to-eat cereals, and the control group, or between cereal eaters and non-cereal eaters.

Adolescent↗
PubMed1977

Monoaminergic synapses, including dendro-dendritic synapses in the rat substantia nigra.

Intraventricular administration of 1 or 2 mg of the osmiophilic "false transmitter" 5-hydroxydopamine (5-OHDA) was used to label monoamine storage and release sites in the rat substantia nigra. Vesicles containing unusually dense cores indicative of the presence of the marker were seen forming from the Golgi apparatus in the cell bodies of medium-sized neurons of the substantia nigra, pars compacta, and from smooth endoplasmic reticulum in the dendrites of those neurons and in small unmyelinated axons of unknown origin. In serial sections, both axons and dendrites containing synaptic vesicles marked with 5-OHDA were seen to form synapses "en passage" in pars compacta, and some presynaptic dendrites containing vesicles filled by the marker were also observed to form contacts with dendrites in pars reticulata. The only identified postsynaptic elements engaging in monoaminergic synapses in the substantia nigra were dendrites of medium-sized pars compacta neurons.

Animals↗
PubMed1977

The substantia nigra of the rat: a Golgi study.

Three variants of the Golgi method were employed to examine the cell types, their dendritic fields and organization and axonal trajectories within the substantia nigra of albino and hooded rats. In both sagittal and coronal sections, large, medium and small neurons were classified on the basis of soma size, extent of dendritic fileds and dendritic caliber. In general nigral cells have three to five primary dendrites that branch relatively infrequently. Some dendrites of all cell types have thinly scattered spines or varicosities. Small cells, found in all areas of the nucleus, have thin dendrites and small, nondirectional dendritic fields. These are considered to be interneurons. The medium cells found in pars compacta, presumed to be the dopaminergic cells of the nigroneostriatal pathway, send long dendrites into pars reticulata perpendicular to the course of pars compacta. In addition, these cells have a number of dendrites which remain in pars compacta. These cells have axons that run medio-dorsally. No axon collaterals were detected. Both large and medium cells are found in pars reticulata. Cells in the dorso-medial aspect of pars reticulata orient rostro-caudally and roughly perpendicular to the course of pars compacta, while cells in the peripeduncular area show a strict orientation which is parallel to the crus cerebri. Some pars reticulata cells emit axon collaterals while others remain unbranced for their observable lenght. Both large and medium cells are also seen in pars lateralis. These cells send long dendrites ventrally into pars reticulata where they run parallel to the crus cerebri, while some shorter dendrites remain in pars lateralis. In total, the substantia nigra appears to have a layered organization: the superior layer is the cellular pars compacta, the second is the dorso-medial area of pars reticulata where both pars compacta and pars reticulata dendrites run rostro-caudally and dorso-ventrally and the third layer is the peripeduncular region where dendrites from all areas run parallel to the crus cerebri.

Animals↗
PubMed1977

Fresnel fringes in STEM.

Experiments carried out with a field emmission STEM show several Fresnel fringes along specimen edges, similar to CTEM observation. Analysis of the data shows agreement with computer profiles for idealized edges and the influence of defocusing distance and collector aperture size is discussed. In very coherent detection conditions the number of visible fringes is limited maily by signal-to-noise ratio considerations. In order to observe the maximum number of fringes, a collector aperture must be chosen so that there is a compromise between the limits imposed by the coherence of the detection and the signal-to-noise ratio.

Electrons↗
PubMed1975

Intravenous diazoxide in acute poststreptococcal glomerulonephritis.

Twenty-six patients with hypertension secondary to acute poststreptococcal glomerulonephritis were treated by the rapid intravenous infusion of diazoxide. The average pretreatment systolic pressure was 159 mm Hg. Five minutes after administration, the average systolic pressure was 122 mm Hg (a 23% reduction). The average initial diastolic pressure was 104 mm Hg, which fell 5 minutes after diazoxide injection to 71 mm Hg (a 32% reduction). No hypotensive episodes were noted. Occasional episodes of nausea occurred. Concentrations of blood glucose increased after administration of diazoxide; however, no values were above 155 mg/dl. Diazoxide appears to be a safe antihypertensive drug that is effective in the treatment of hypertension secondary to acute poststreptococcal glomerulonephritis.

Acute Disease↗