Connections of the posterior nucleus of the amygdala. The connections of a relatively homogeneous band of neurons in the caudal amygdala have been examined with anterograde and retrograde axonal tracing methods in the rat. This region, called here the posterior nucleus of the amygdala (PA), corresponds in part to an area that has been referred to as the cortico-amygdaloid transition area, posterior part of the medial nucleus of the amygdala, amygdalo-hippocampal transition area, and posteromedial basal nucleus. Experiments with fluorogold and phaseolus vulgaris leucoagglutinin (PHAL) indicate that the major neuronal input to the PA arises in the ventral premammillary nucleus, and that substantial projections also arise in olfactory-related areas such as the medial nucleus of the amygdala, bed nucleus of the accessory olfactory tract, and posterior cortical nucleus of the amygdala, as well as in the ventral subiculum and adjacent parts of hippocampal field CA1. Other seemingly minor inputs, including cholinergic fibers from the substantia innominata, dopaminergic fibers from the ventral tegmental area, and serotoninergic fibers from the dorsal nucleus of the raphe, were also identified. The efferent projections of the PA as determined with the PHAL method appear to follow five major routes: 1) a relatively small group of laterally directed fibers innervates the dorsal endopiriform nucleus, and a few of these fibers reach cortical area TR and the lateral entorhinal area; 2) another small group of fibers courses medially to innervate the ventral subiculum and adjacent parts of field CA1; 3) many fibers course ventrally to innervate the outer molecular layer of the medial part of the posterior cortical nucleus of the amygdala; 4) a moderate group of fibers courses rostrally to innervate primarily the posterodorsal part of the medial nucleus of the amygdala, although some fibers continue on to end less densely in rostral parts of the medial nucleus of the amygdala before leaving the amygdala through the ansa peduncularis; and 5) the major output of the PA courses through the stria terminalis. One branch of this pathway massively innervates the principal nucleus of the bed nuclei of the stria terminalis before entering the medial hypothalamus, where it ends massively in the anteroventral periventricular and medial preoptic nuclei, ventrolateral part of the ventromedial nucleus and adjacent parts of the basal lateral hypothalamic area, and ventral premammillary nucleus. The other branch sends fibers to the ventral lateral septal nucleus, nucleus accumbens, olfactory tubercle, and infralimbic area of the prefrontal cortex.(ABSTRACT TRUNCATED AT 400 WORDS)


Projections of the ventral subiculum to the amygdala, septum, and hypothalamus: a PHAL anterograde tract-tracing study in the rat. The projections of the ventral subiculum are organized differentially along the dorsoventral (or septotemporal) axis of this cortical field, with more ventral regions playing a particularly important role in hippocampal communication with the amygdala, bed nuclei of the stria terminalis (BST), and rostral hypothalamus. In the present study we re-examined the projection of the ventral subiculum to these regions with the Phaseolus vulgaris leucoagglutinin (PHAL) method in the rat. The results confirm and extend earlier conclusions based primarily on the autoradiographic method. Projections from the ventral subiculum course either obliquely through the angular bundle to innervate the amygdala and adjacent parts of the temporal lobe, or follow the alveus and fimbria to the precommissural fornix and medial corticohypothalamic tract. The major amygdalar terminal field is centered in the posterior basomedial nucleus, while other structures that appear to be innervated include the piriformamygdaloid area, the posterior basolateral, posterior cortical, posterior, central, medial, and intercalated nuclei, and the nucleus of the lateral olfactory tract. Projections from the ventral subiculum reach the BST mainly by way of the precommissural fornix, and provide rather dense inputs to the anterodorsal area as well as the transverse and interfascicular nuclei. The medial corticohypothalamic tract is the main route taken by fibers from the ventral subiculum to the hypothalamus, where they innervate the medial preoptic area, "shell" of the ventromedial nucleus, dorsomedial nucleus, ventral premammillary nucleus, and cell-poor zone around the medial mammillary nucleus. We also observed a rather dense terminal field just dorsal to the suprachiasmatic nucleus that extends dorsally and caudally to fill the subparaventricular zone along the medial border of the anterior hypothalamic nucleus and ventrolateral border of the paraventricular nucleus. The general pattern of outputs to the hypothalamus and septum is strikingly similar for the ventral subiculum and suprachiasmatic nucleus, the endogenous circadian rhythm generator.


Projections of the ventral premammillary nucleus. The projections of the ventral premammillary nucleus (PMv) have been examined with the Phaseolus vulgaris leucoagglutinin (PHAL) method in adult male rats. The results indicate that the nucleus gives rise to two major ascending pathways and a smaller descending pathway. One large ascending pathway terminates densely in most regions of the periventricular zone of the hypothalamus, with the notable exception of the suprachiasmatic, suprachiasmatic preoptic, and median preoptic nuclei. This pathway is in a position to influence directly many cell groups known to regulate anterior pituitary function. The second large pathway ascends through the medial zone of the hypothalamus and densely innervates the ventrolateral part of the ventromedial nucleus and adjacent basal parts of the lateral hypothalamic area, medial preoptic nucleus, principal nucleus of the bed nuclei of the stria terminalis, ventral lateral septal nucleus, posterodorsal part of the medial nucleus of the amygdala, posterior nucleus, and immediately adjacent regions of the posterior cortical nucleus of the amygdala. It is already known that these regions are major components of the sexually dimorphic circuit, and, interestingly, that they provide the major neural inputs to the PMv. The smaller descending projection from the PMv seems to innervate preferentially the posterior hypothalamic nucleus, although a small number of fibers appear to end in the tuberomammillary nucleus, supramammillary nucleus, specific regions of the medial mammillary nucleus, interfascicular nucleus, interpeduncular nucleus, periaqueductal gray, dorsal nucleus of the raphe, laterodorsal tegmental nucleus, Barrington's nucleus, and locus coeruleus. Relatively sparse terminal fields associated with ascending fibers were also observed in the dorsomedial nucleus of the hypothalamus; in the nucleus reuniens, parataenial nucleus, paraventricular nucleus of the thalamus, and mediodorsal nucleus; in the central nucleus of the amygdala, anterodorsal part of the medial nucleus of the amygdala, posterior part of the basomedial nucleus of the amygdala; and in the ventral subiculum and adjacent parts of hippocampal field CA1, and the infralimbic and prelimbic areas of the medial prefrontal cortex. Taken as a whole, the evidence suggests that the PMv receives two major inputs--one from the sexually dimorphic circuit, and the other from the blood in the form of gonadal steroid hormones--and gives rise to two major outputs: one (perhaps feed-forward) to the neuroendocrine (periventricular) zone of the hypothalamus, and the other (perhaps feed-back) to the sexually dimorphic circuit.


Embryonic development of synapses on spiking local interneurones in locust. The development of synapses on an identified population of spiking local interneurones in the thoracic ganglia of embryonic locusts was examined by means of intracellular horseradish peroxidase injection and electron microscopy. In adult locusts, spiking local interneurones of the midline group receive direct inputs onto a ventral field of branches from leg mechanosensory afferents and in turn make output synapses, mainly from a dorsal field of branches, directly upon leg motor neurones, nonspiking local interneurones, and intersegmental interneurones. The aim of this study is to examine the development of these connections. These interneurones are born relatively late in embryogenesis and are not identifiable until approximately 55% of development. At this time (55-60%) only simple filopodial contacts or punctate contacts are evident between the stained interneurones and other neurones. By 65-70% embryogenesis, vesicles are found adjacent to regions where apposed membranes are symmetrically thickened with amorphous electron-dense material. These symmetrical contacts lack distinct presynaptic bar-shaped densities and therefore, are not considered to be synapses. At this stage, the interneurones do not produce action potentials upon intracellular injection of depolarising current. Morphologically identifiable synapses, with vesicles, a presynaptic bar, and relatively little postsynaptic density, are first evident at 70-75%, coincident with the time of arrival of the majority of leg mechanosensory afferents into the central nervous system. At this stage, action potentials and synaptic potentials are also recorded for the first time. The midline spiking interneurones thus become electrically excitable when synapses are first recognisable, at approximately 70% embryogenesis. Most of the synapses found on the interneurones are outputs. The ratio of outputs to inputs on ventral branches is 7.5:1 which contrasts markedly to the adult ratio of 1:2. By 85-90%, output synapses still predominate on the ventral branches, but the ratio of outputs to inputs is reduced to almost 2:1. Dorsal branches have predominantly output synapses throughout embryogenesis. The ratio of dorsal outputs to inputs at 85-90% is 8.5:1 which compares with the adult ratio of 6.5:1. At this stage, action potentials and synaptic activity are always recorded.


Topographic organization of cortical and subcortical projections to posterior cingulate cortex in the cat: evidence for somatic, ocular, and complex subregions. The posterior cingulate area (CGp) of the cat consists of cortex on the exposed cingulate gyrus and in the adjacent ventral bank of the splenial sulcus. We have placed deposits of distinguishable fluorescent tracers at multiple restricted sites in CGp and have analyzed the distribution throughout the forebrain of neurons labeled by retrograde transport. Cortical projections to CGp arise (in approximately descending order of strength) from anterior cingulate cortex; prefrontal cortex and premotor areas including the frontal eye fields; visual areas including especially areas 7 and 20b; parahippocampal areas; insular cortex; somesthetic areas; and auditory areas. Corticocortical pathways are organized topographically with respect to the posterior-anterior axis in CGp. Projections from prefrontal cortex and other areas with complex (as opposed to sensory, motor, or limbic) functions are concentrated posteriorly; projections from visual and oculomotor areas are concentrated at an intermediate level; and projections from areas with somesthetic and somatomotor functions are concentrated anteriorly. Thalamic projections to CGp arise from the anterior nuclei (AD, AV, and AM), from restricted portions of the ventral complex (VAd, VAm, and VMP), from discrete sectors of the lateral complex (LD, LPs, and LPm), from the rostral crescent of intralaminar nuclei (CM, PC, and CL), and from the reuniens nucleus. Projections from AM, VAd, LD, and LPs are spatially ordered in the sense that more ventral thalamic neurons project to more anterior cortical sites. Projections from AV and AD are stronger at more posterior cortical sites but do not show other signs of topographic ordering. Projections from LPm, CM, PC, CL, and RE are diffuse. We conclude (1) that cortical afferents of CGp derive predominantly from neocortical areas including those with well established sensory and motor functions; (2) that limbic projections to CGp originate primarily in structures, including the hippocampus, which are associated with memory, as opposed to structures, including the amygdala, which are associated with emotional and instinctual behavior; and (3) that CGp contains subregions in which complex, ocular, or somatic afferents predominate.


Acetylcholinesterase reactivity in the frontal cortex of human and monkey: contribution of AChE-rich pyramidal neurons. Light and electron microscopic histochemistry were used to analyze the distribution of the enzyme acetylcholinesterase (AChE) in the frontal cortex of macaque monkey and human. In prefrontal, premotor, prelimbic, and medial paralimbic areas, AChE reactivity showed a characteristic bilaminar appearance due to a combination of positive neuronal and fiber labeling in deep layer III and layer V. In addition, layer I contained dense AChE-reactive fiber plexuses labeled throughout the frontal areas. One of the major issues addressed in this study was whether pyramidal neurons in the nonhuman primate cortex express AChE reactivity, as has been reported for humans. Three different histochemical methods were applied to provide confidence in the reliability of the results. Light microscopic analysis revealed strongly reactive, intensely stained pyramidal neurons in monkey as well as in the human. Further, these AChE-rich neurons exhibited the same pattern of laminar and regional variation in both species. In the prefrontal and premotor areas, AChE-rich pyramidal neurons predominated in layer III. In the motor cortex, they were also concentrated in layer III, but numerous AChE-rich pyramids were observed in layer V. In contrast, medial paralimbic areas had more AChE-rich neurons in layer V than in layer III. Finally, at the electron microscopic level, the subcellular distribution of AChE histochemical product in pyramidal neurons was identical in both monkey and human. The only difference noted between the two species was that the density of AChE-rich pyramidal neurons was greater in humans than in monkeys. Since nonhuman primates possess a system of AChE-reactive pyramidal neurons similar to human, they provide a potentially useful animal model for analyzing acetylcholinesterase neuronal systems in the cortex, which are compromised in various neuropathological diseases like Alzheimer's disease.


Normal development and effects of neonatal infraorbital nerve damage upon the innervation of the trigeminal brainstem complex by primary afferent fibers containing calcitonin gene-related peptide. Immunocytochemistry was used to study the normal development and response to infraorbital nerve (ION) damage of the innervation of the trigeminal (V) brainstem complex by axons recognized by an antibody directed against calcitonin gene-related peptide (CGRP). CGRP-like immunoreactivity (CGRPLI) was present in axons that occupied the outer V spinal tract (TrV) at all levels of the V brainstem complex. Almost no fibers terminated within V nucleus principalis (PrV), but there was dense CGRPLI in the supratrigeminal nucleus. There was also very little CGRPLI within rostral V subnucleus oralis (SpO). However, in the caudal one-half of the nucleus, a dense elongated patch of immunoreactivity was consistently present just medial to TrV. Only occasional CGRP-positive axons could be seen within V subnucleus interpolaris (SpI), but the paratrigeminal nucleus contained dense immunoreactivity. Trigeminal subnucleus caudalis (SpC) also contained CGRPLI that was very dense in lamina I and the outer portion of lamina II. Scattered terminals were also present in layers III and IV and dense terminal clusters were in lamina V. CGRP-immunoreactive neurons were present in the V ganglion by embryonic (E-) day 16 and immunoreactive axons could be seen in the V brainstem complex on E-17. At birth, CGRP-positive axons in the V brainstem complex had achieved a distribution very similar to that in adult rats. The major difference between the patterns of labelling in neonates and adults was the presence of relatively large numbers of CGRP-positive fibers in ventral PrV and SpO of the former animals. The disappearance of these fibers was completed by the middle of the third postnatal week. Transection of the ION on the day of birth had little effect upon CGRP in SpO, SpI, and SpC, but it did result in an increase in CGRP-positive fibers in PrV ipsilateral to the damaged nerve. When considered together with previous findings, these results suggest that CGRP-positive axons express this peptide well after they have entered the V brainstem complex and that the central terminal field of these fibers is not substantially altered by a manipulation which results in the death of nearly 60% of all V primary afferent neurons.


The superficial plexiform layer: a third retinal association area. Electron microscopy enables the identification of a new association area in the mammalian retina. It is a region whose processes and synaptic junctions form a diffuse and intermittent layer bridging the boundary between the optic nerve fibre layer and ganglion cell layer. It involves displaced amacrine cells, retinal ganglion cells and probably interplexiform cell processes. Because it is close to the vitreal surface of the retina and has several properties of a plexiform layer, it has been named the superficial plexiform layer. It is much more sparse than the outer or inner plexiform layers in the rabbit, but contains a significant and substantial density of 6,100 synapses/mm2 near the visual streak. Morphological criteria distinguish two classes of synapses in the new association area. One has features of Colonnier's symmetric type and is formed by amacrine-like processes or their terminals, onto other amacrine-like processes or the cell bodies, dendrites and axon hillocks of some large ganglion cells. It makes up 79% of the population at a density of 4,800 synapses/mm2 in the examined sample. The second class arises from large processes of the fibre layer, which resemble axons rather than amacrine cell branches, has Colonnier's asymmetric form, and synapses onto a variety of other neuronal processes and cells. At a local density of 1,300/mm2 this type forms 21% of the population. A series of experiments including Wallerian degeneration, retrograde degeneration, electron microscopy and horseradish peroxidase (HRP) transport was employed to determine the nature of the large synapse-forming processes of the fibre layer that were the most amenable to investigation. It is concluded that the processes project into the optic nerve because they can be filled with HRP by retrograde transport from the end of the transected optic nerve. Although this result is based on limited evidence, it is complemented by the observation that the majority of the fibres undergo retrograde degeneration within 25 days of optic nerve section. It is concluded that the processes are either centrifugal fibres or the axons of retinal ganglion cells. The persistence of a relatively normal density of synapse-forming large fibres for seven days after optic nerve section, without Wallerian degeneration, argues that they are not the terminals of centrifugal axons. This conclusion is complemented by a separate class of profiles that did degenerate in this short period and are concluded to represent the centrifugal fibres. The large synapsing processes of the fibre layer are concluded to be the axons of some large ganglion cells.(ABSTRACT TRUNCATED AT 400 WORDS)


Projections to the medial superior olive from the medial and lateral nuclei of the trapezoid body in rodents and bats. In this study we present direct evidence of axonal projections from both the medial and lateral nuclei of the trapezoid body to the medial superior olive. Projections were traced by intracellularly labeling cells and axons in a tissue slice preparation of two rodent species, Mus musculus and Meriones unguiculatus and two bat species, Eptesicus fuscus and Pteronotus parnellii. The main axon of most principal cells in the medial nucleus of the trapezoid body gives off one or more collateral branches which arborize within the medial superior olive. These collateral axons form small bouton-like swellings which primarily contact somata within the central cell column in the medial superior olive. Likewise, labeled elongate and multipolar cells of the lateral nucleus of the trapezoid body send axons to both the medial and lateral superior olives. These axons also form perisomatic contacts in both target nuclei. These two sets of projections may relay ascending input to the medial superior olive and the lateral superior olive; the medial nucleus of the trapezoid body is known to relay input from the contralateral ventral cochlear nucleus, and the lateral nucleus of the trapezoid body may relay input from the ipsilateral ventral cochlear nucleus. These projections offer two routes for indirect, possibly inhibitory input to reach the medial superior olive from both cochlear nuclei. These indirect, inhibitory pathways may parallel the direct excitatory projections the medial superior olive receives from each cochlear nucleus.


Ultrastructural development of the medial superior olive (MSO) in the ferret. When ferrets are born, four weeks before the onset of hearing, few synapses are evident in the medial superior olive (MSO). The synapses present are immature and almost exclusively found in the neuropil. The MSO somata are virtually devoid of synaptic contacts but are contacted by fine glial processes that increasingly ensheathe the somata during the first postnatal week. By P12, somatic synaptogenesis in the MSO is evident. Initially the terminals contain vesicles of irregular shape, size, and distribution. The glial lamellae appear to withdraw as the synaptic contacts form but continue to cover the asynaptic portions of the cell surface. The lamellae frequently extend from ensheathing the soma to encapsulate the immature terminals. During the next two weeks, synaptic density and terminal encapsulation proceed until the somata is surrounded by encapsulated synaptic terminals as in the adult ferret MSO. While most immature terminals contain round vesicles, during the first postnatal week some terminals with nonround vesicles can be distinguished. The first distinction between types of nonround vesicle-containing terminals, i.e., pleiomorphic and ovoid, is in the second postnatal week. This distinction becomes increasingly clear and by the end of the first postnatal month, terminal types can be reliably categorized. These observations indicate that: (1) synapses are present in the MSO neuropil one month prior to the onset of hearing, (2) the major period of synaptogenesis begins approximately two weeks prior to the onset of hearing, and (3) glial lamellae ensheathe MSO somata prior to the onset of somatic synaptogenesis, withdraw as synapses form, and subsequently re-extend to encapsulate newly formed synapses.


Early postnatal alcohol exposure acutely and permanently reduces the number of granule cells and mitral cells in the rat olfactory bulb: a stereological study. This study demonstrates that exposure to alcohol during a period of rapid brain growth can lead to severe and permanent deficits in the number of granule cells and mitral cells in the main olfactory bulb. Sprague-Dawley rat pups were reared artificially and were administered alcohol over postnatal days (PD) 4 through 9, a period of brain development comparable to part of the human third trimester. The daily alcohol dose of 6.6 g/kg was concentrated into two of the twelve daily feedings, producing high peak blood alcohol concentrations followed by near total clearance. Pups were either sacrificed on PD10 or were allowed to grow to adulthood and sacrificed on PD115. The total number of granule cells and mitral cells in the main olfactory bulb were estimated with the aid of unbiased stereological principles and systematic sampling techniques. Exposure to alcohol resulted in significant reductions in the number of both granule cells and mitral cells on PD10. Significant deficits in both neuronal populations remained on PD115. The results support the hypothesis that alcohol exposure can kill developing neurons and lead to permanent neuronal deficits. Substantial developmental changes also occurred in the total number of mitral cells and granule cells between PD10 and PD115 in the control groups. In untreated rats, the number of granule cells increased from 2.20 x 10(6) on PD10 to 5.06 x 10(6) on PD115, while the number of mitral cells decreased from 5.30 x 10(4) to 4.33 x 10(4) over the same time period. These results demonstrate that there is a natural loss of mitral cells during postnatal development at the same time that granule cell number is increasing.


Distribution of the peptide Ala-Pro-Gly-Trp-NH2 (APGWamide) in the nervous system and periphery of the snail Lymnaea stagnalis as revealed by immunocytochemistry and in situ hybridization. Immunocytochemistry and in situ hybridization were used to identify 200-250 central neurons that synthesize and contain the peptide APGWamide in the central nervous system of Lymnaea. The majority of these cells reside within the right anterior lobe of the cerebral ganglion and most appear to have projections to the ventral lobe of the ganglion. The neurites then branch to innervate the lobe and to send further projections into the penial nerve and to the PeIb cluster of the right pedal ganglion. The right ventral lobe also contains a cluster of about 30-40 somata, which apparently synthesize and contain APGWamide. Other populations of cells found in both the right and left anterior lobes project ipsilaterally to the pleural, parietal, and visceral ganglia. Prominent somata are also located in clusters in the visceral and right parietal ganglia. These cells project ipsilaterally into caudal neuropilar regions of the cerebral ganglia. Peripheral projections of central neurons form a dense plexus of varicose, APGWamide-containing fibres in superficial layers of the penis and preputium. Other peripheral projections were noted in the prostate and vas deferens. No peripherally located cell bodies appeared to contain or synthesize the peptide. The results show that APGWamide is widely present in the central nervous system and male reproductive organs and suggest that it plays a major role in control of reproduction.


Immunocytochemical identification of primary olfactory afferents in rainbow trout. We have used a combination of techniques to analyze the primary olfactory projection in trout: anterograde tract tracing with horseradish peroxidase (HRP) and immunocytochemistry with antisera to olfactory marker protein (OMP) and to keyhole limpet hemocyanin (KLH). HRP labeling and the OMP antiserum revealed a subset of ciliated receptor neurons with a wide dendrite that lacked the protruding knob found on other receptor neurons. The organization of the primary olfactory axons was clearly revealed by antisera to KLH, which reacted with no other neurons. When visualized with anti-KLH, fascicles of olfactory axons penetrated the basal lamina of the olfactory rosette at scattered sites and converged to form the olfactory nerve. Fascicles within the olfactory nerve traveled parallel to the long axis of the nerve until resorted by extensive intermixing as they entered the olfactory bulb. Within the olfactory bulb, most axons terminated in nine discrete terminal fields in the glomerular layer; however, a few olfactory nerve axons projected into the ventral medial telencephalon. Fascicles supplying each terminal field in the glomerular layer followed distinctive trajectories within the olfactory nerve layer. Axons ending in two terminal fields made brush-like terminations rather than the glomerular terminations characteristic of the remaining seven fields. After unilateral olfactory nerve transection, returning olfactory axons reestablished the normal pattern of terminal fields within 14 weeks. It is likely that the organization of afferents in the trout olfactory bulb is similarly well regulated during normal receptor cell replacement.


Morphological types of ganglion cells in the dog and wolf retina. The morphological types of ganglion cells in the dog and wolf retina were studied by intracellular staining with Lucifer Yellow. These retinae contain a range of ganglion cell types that closely correspond to those found in cat retina: alpha cells with large somata and large, relatively densely branched dendritic trees; beta cells with medium-sized somata and small, densely branched dendritic trees; and a variety of other types with smaller somata and varying dendritic branching patterns and dendritic field sizes. The correspondence of canine and cat ganglion cell types strengthens the view that there is a common set of ganglion cell types in carnivores. Alpha and beta cell dendritic trees of dog and wolf are monostratified in either the inner or the outer part of the inner plexiform layer, suggesting an on/off dichotomy in the response to light. Dendritic field sizes of dog alpha and beta cells increase from the central area to peripheral retina: alpha cell fields from 160-200 microns to about 1,100 microns diameter, and beta cell fields from 25 microns to about 360 microns diameter. These sizes are quantitatively very similar to those found in cat retina. The close qualitative and quantitative morphological correspondence of cat and dog ganglion cells suggests that they are also functionally very similar. It is likely that dog alpha cells have brisk-transient (Y), and dog beta cells brisk-sustained (X) concentric receptive fields. From the smallest beta cell sizes it is concluded that the visual acuity of the dog may be as good as that of the cat.


Heterogeneity of sensory hair cells in a fish ear. The ultrastructure of sensory hair cells in the utricle of the cichlid fish, Astronotus ocellatus, the oscar, was studied by transmission electron microscopy of serial ultrathin sections from different regions of the epithelium. Two distinctly different types of hair cell were found, one located in the striolar region of the epithelium and the other in the extrastriolar region. Striolar hair cells have a well-defined perinuclear cisterna located just below the nucleus, and large perinuclear mitochondria. Synaptic bodies of striolar cells are small and located in clusters, while those in extrastriolar cells are relatively large and individually dispersed. The extrastriolar hair cell closely resembles the amniote type II hair cell. On the basis of these data, and consistent with earlier studies, it appears that the striolar hair cells closely resemble amniote type I hair cells in many significant ways. Thus we have called them type I-like cells. The extrastriolar hair cells appear to be typical of eighth nerve mechanoreceptors commonly described for fish and closely resemble the amniote type II hair cell.


A microbiological, histopathological and immunohistological study of the intragastric inoculation of Listeria monocytogenes in mice. The course of murine infection after intragastric inoculation of L. monocytogenes was investigated by immunocytochemical, histopathological and microbiological techniques. L. monocytogenes antigen was observed in epithelial cells of intestinal mucosa overlying Peyer's patches, but not in mucosa devoid of them. This suggests that penetration of L. monocytogenes into the host organism may take place through epithelium overlying Peyer's patches. The efficiency of bacterial penetration appeared to be low, as shown by the small amounts of L. monocytogenes antigen detected and the low counts of bacteria in organs. Gross or histopathological lesions in the intestinal tract were not observed. The presence of L. monocytogenes in spleen, liver and in maxillary and mesenteric lymph nodes, confirmed that the systemic course of infection by this route of inoculation is similar to that of the parenteral routes. The results emphasize the subclinical character of murine listeriosis by the oral route.


Comparative histopathological study of rabbit haemorrhagic disease (RHD) and European brown hare syndrome (EBHS). Histopathological lesions due to rabbit haemorrhagic disease (RHD) and European brown hare syndrome (EBHS) were studied in 35 rabbits and seven hares. Both rabbits (Oryctolagus cuniculus) and hares (Lepus europeus) regularly showed severe necrotizing hepatitis. In RHD, coagulation necrosis, mainly confined to the periphery of the lobules, was consistently found. In EBHS, lytic necrosis affecting the whole lobule was conspicuous, at least in severe cases. Particularly in EBHS, necrotic hepatocytes exhibited a special kind of karyorrhexis. In rabbits with a subacute or subclinical form of disease, early liver cirrhosis was observed. Depletion of lymphocytes was a regular feature in spleens of rabbits and was frequently found in hares. In RHD, disseminated intravascular coagulation (DIC) and haemorrhages in different organs, especially in kidneys and lungs were constant findings. DIC was never seen in EBHS and haemorrhages were an infrequent finding.


Epithelioid sarcoma in a dog.

Epithelioid sarcoma in a dog. A tumour in an 11-year-old male crossbred Fox Terrier, showing the clinical and pathological features of epithelioid sarcoma in man is reported. Clinical aspects, location, peculiar pattern of spread and evolution, together with histopathological and immunohistological findings of this rare tumour simulating a granuloma are described. Controversial histogenesis is discussed.


Cell-mediated immune response in rotavirus-infected calves: leucocyte migration inhibition assay. The cell-mediated immune (CMI) response was determined in rotavirus-infected calves by leucocyte migration inhibition assay with blood, spleen, mesenteric lymph node and intestinal lymphocytes. The inhibition of migration was more prominent in intestinal and mesenteric lymph node lymphocytes than in spleen and blood. In rotavirus-infected calves, the assay indicated the presence of CMI response which was more prominent at the local site of infection.


Detection of the binding of IgG2a and IgG2b on the surface of macrophages from mice chronically infected with lactic dehydrogenase virus. This study showed that sera from mice chronically infected with lactic dehydrogenase virus (LDV) contained virus-antibody complexes (IC). IgG2a and IgG2b, but not IgG1, IgG3, IgM or IgA, were demonstrated on the surface of macrophages from chronically infected mice. These results suggest that IC in the circulation may bind to Fc receptors for IgG2a and IgG2b on the surface of macrophages and lead to the modulation of macrophage function seen in chronically LDV-infected mice.


Effect of prostaglandin E2 on plasma lactic dehydrogenase activity in (NZB x NZW)F1 mice with a chronic infection of lactic dehydrogenase virus. The effect of prostaglandin E2(PGE2) on blood LDH values was investigated in (NZB x NZW)F1 mice with or without an established infection with lactic dehydrogenase virus (LDV). Plasma LDH decreased in infected mice treated with PGE2, but increased in infected mice treated with indomethacin, an inhibitor of PGE2. However no significant effect on LDH occurred in uninfected mice treated with PGE2 or indomethacin. To investigate the mechanisms of decreased LDH activities resulting from treatment with PGE2, clearance tests were performed. Clearance of LDH-5, but not LDH-1, was faster in PGE2-treated mice than in non-treated mice, whether or not they were infected with LDV. The results suggest that enhanced clearance of LDH-5 in mice treated with PGE2 may account for the fall in plasma LDH in LDV-infected mice.


Mycoplasma ovipneumoniae infection in Zimbabwean goats and sheep. The prevalence of Mycoplasma ovipneumoniae (MO) in three Communal Lands flocks of goats on the outskirts of Harare is described. In a single sampling of nasal swabs from 172 randomly selected, apparently healthy goats, 112 animals were identified as carriers of MO. The three flocks had a history of occasional deaths, following chronic and subacute pneumonia associated with isolation of MO as the only identifiable pathogen. Attempts to induce clinical pneumonia in groups of 6 to 8-week-old kids and lambs with local isolates of MO were not successful. However, MO was consistently cultured from the trachea, lungs, lymph node and thymus of some test animals. Cuffing interstitial pneumonia was also observed in these animals. Infection of the thymus occurred; this has not previously been reported with any Mycoplasma sp. The animals did not produce detectable serum antibodies to MO nor were they reactive to MO antigen in a tuberculin-type hypersensitivity test. The possibility that a state of immunotolerance may have been responsible for failure to develop clinical pneumonia is discussed.


Localization of African swine fever viral antigen, swine IgM, IgG and C1q in lung and liver tissues of experimentally infected pigs. An immunohistological study was carried out on lungs and livers of pigs experimentally infected with two different African swine fever virus (ASFV) isolates. ASFV antigen, swine immunoglobulins (IgM and IgG) and (Clq) complement were demonstrated in both organs at different stages of infection. The ASFV antigen was mainly found in mononuclear phagocytic system (MPS) cells. Immunoglobulins and complement were observed in plasma, infected and non-infected phagocytic cells and cell debris. These findings suggest the presence, in acute infection, of immune complexes which may be involved in immunopathogenic mechanisms.


Antibody response and antibody affinity maturation in cats with experimental proliferative immune complex glomerulonephritis. An experimental model of proliferative glomerulonephritis (GN) in the cat, which closely resembles human proliferative forms of GN, has been used to study the role of antibody and antibody affinity in the development of immune complex-mediated renal disease. The serum IgG and IgM antibody response to antigen, average antibody affinity (avidity) and affinity heterogeneity of the IgG and IgM populations was assessed at varying times after commencement of chronic immunization with the antigen, human serum albumin (HSA), by enzyme immunoassay. Cats could be classified according to whether they were "low", "intermediate" or "high" IgG responders, by quantification of serum IgG values. Cats with the lowest serum IgG values failed to develop glomerulonephritis. However, there was no relationship between actual IgG values and the severity of the induced disease. In contrast to IgG, there was no division of cats into low or high IgM anti-HSA responders. Again, cats with the lowest IgM values failed to develop GN, but, more interestingly, a late, marked increase in serum IgM anti-HSA occurred only in cats that developed clinical signs of GN (anterior uveitis and nephrotic syndrome). Maturation of average, functional IgG affinity (avidity) for HSA following chronic immunization was clearly demonstrated for all cats. At the end of the experiment, all cats had IgG of high affinity for HSA and the average affinity heterogeneity of the IgG populations was less than in measurements taken earlier. Values of IgG affinity at the end of the experiment were very similar both in cats which developed GN and in those which remained clinically, biochemically and pathologically normal. In contrast to IgG antibody, some cats developed IgM of increased affinity, whilst others produced antibody of reduced affinity, following chronic immunization. There was no correlation between the development of disease and the production of either low or high affinity IgM antibody. Data indicated that an alteration in IgM affinity occurred at a late stage, as serum IgM levels increased, in cats which progressed to develop GN. These findings suggested that an increase in both serum IgG and IgM anti-HSA values, in particular IgM, was associated with the development of a more severe immune complex renal disease in these cats. Although there was no evidence that differences in the average affinity of either the IgG or IgM antibody populations for HSA, were associated with the development of disease, the increase in IgM values was also accompanied by a concomitant alteration in IgM affinity for antigen.(ABSTRACT TRUNCATED AT 400 WORDS)


Soft tissue reconstruction with skin grafting. Free skin grafts for soft tissue reconstruction can be classified into three types: full-thickness skin grafts, split-thickness skin grafts, and composite grafts. The indications, techniques, donor site considerations, and postoperative complications of each type of skin graft are reviewed.


Expression of adhesion proteins involved in cell-cell and cell-matrix interactions in the skin of patients with progressive systemic sclerosis. Lymphocytic infiltration and activation of connective tissue metabolism in the early phase of progressive systemic sclerosis (PSS, scleroderma) may be critically influenced by cellular adhesion molecules (CAMs), which mediate cell-cell and cell-extracellular matrix interactions. The tissue distribution might demonstrate a pathogenetic role of these adhesion molecules in early edematous and chronic fibrotic scleroderma. We investigated by immunohistochemical techniques the in situ expression and distribution of beta 1 and beta 2 integrins, selectins, and CAMs of the immunoglobulin superfamily in patients with scleroderma. In the early disease stage a moderate percentage of perivascular CD3+/CD4+/TCR alpha/beta + lymphocytes showed expression of the alpha 3, alpha 5, and beta 1 chains and, to a lesser degree, of the alpha 1, alpha 2, alpha 4 and alpha 6 subunits. In contrast to chronic PSS, LFA-1 alpha, LFA-1 beta and ICAM-1 expression on mononuclear infiltrating cells was seen more frequently in acute scleroderma. Different percentages of fibroblasts expressed alpha 1-, alpha 3-, alpha 5- and beta 1-integrin chains. In acute PSS ICAM-1 was expressed especially by fibroblasts located around perivascular inflammatory infiltrates as well as by endothelial cells (ECs). A few ECs expressed alpha 2 beta 1 integrins. Our observations suggest that CAMs are intimately involved in early pathogenetic events in scleroderma, mediating cellular interactions between lymphocytes, ECs, and fibroblasts, as well as homing and tissue targeting of mononuclear infiltrating cells.


Serum androgens and depression in women with facial hirsutism. Studies on the psychopathologic aspects of hirsutism are sparse. Attempts to correlate these aspects with either the extent of the facial hirsutism and/or circulating serum androgens are virtually nonexistent. This study evaluates the psychopathologic aspects of hirsutism and correlates these findings with the extent of the facial hirsutism as well as with the circulating serum androgens. Our purpose was to assess the psychopathologic aspects of facial hirsutism and to determine whether any correlation exists between these findings and either the extent of the facial hirsutism or the circulating serum androgens. Twenty consecutive women with facial hirsutism were studied by administration of psychologic tests (DeRogatis Symptom Inventory and the Affects Balance Scale). The results of these tests were correlated with the grade of facial hirsutism as well as serum levels of total testosterone (T), biologically active testosterone (BT), free testosterone (FT), dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate (DHEA-S), and androstenedione (A-dione). Significant levels of depression were found. No correlation was found between the psychopathologic measurements and the extent of facial hirsutism or serum levels of T, DHEA, DHEA-S, and A-dione. Significant correlations were found between depression and serum levels of FT and BT. There is an increased incidence of depression in facially hirsute women and this correlates with their circulating active testosterone levels and not with the extent of their facial hirsutism.


Effectiveness of various barrier preparations in preventing and/or ameliorating experimentally produced Toxicodendron dermatitis. Despite extensive research on hyposensitization and prior application of topical barrier preparations, efforts to prevent Toxicodendron dermatitis have been only minimally successful. Seven different barrier creams were evaluated for topical protection against experimentally produced Toxicodendron dermatitis in a randomized, double-blind study. Twenty patients had the seven barrier creams randomly applied to eight test sites (one untreated area as control) on each forearm before application of the Toxicodendron extract. Development of Toxicodendron dermatitis was followed for 8 days, with measurements of erythema, induration, vesiculation, and global severity taken at each site on days 1, 2, 3, 4, and 7 after Toxicodendron application. The barrier creams Stokogard, Hollister Moisture Barrier, and Hydropel significantly reduced the erythema, induration, and global severity of Toxicodendron dermatitis and did not differ from each other. The percent reductions in global dermatitis severity per day of assessment for the seven barriers in order of effectiveness were as follows: Stokogard, 59%; Hollister Moisture Barrier, 52%; Hydropel, 48%; Ivy Shield, 22%; Shield Skin, 13%; Dermofilm, 13%; and Uniderm, -9%. During the 8-day period, a significantly greater number of test sites pretreated with Stokogard, Hollister Moisture Barrier, and Hydropel were free of dermatitis compared with control sites and sites treated with the other four barriers. The results indicate that Stokogard, Hollister Moisture Barrier, and Hydropel are effective in the prevention of Toxicodendron dermatitis.


A characteristic cutaneous direct immunofluorescent pattern associated with Ro(SS-A) antibodies in subacute cutaneous lupus erythematosus. Antibodies to Ro(SS-A) are present in most patients with subacute cutaneous lupus erythematosus (SCLE). Patients with SCLE also have cutaneous immune deposits. However, no correlation of Ro(SS-A) antibodies with immune deposits in skin biopsy specimens has been described. The purpose of this study is to describe characteristic direct immunofluorescence (IF) findings in 32 patients and their association with serum antibodies and clinical diagnosis. Serum from patients with characteristic cutaneous direct IF findings was examined for antinuclear antibodies by indirect IF and for antibodies to ribonucleoprotein, Sm, Ro(SS-A), and La(SS-B) by gel immunodiffusion. Twenty-two of 32 patients who exhibited discrete speckled IgG staining predominantly, but not exclusively, of the basal cell cytoplasm had SCLE. Ro(SS-A) antibodies were identified in 23 of 26 patients and Ro(SS-A) and/or La(SS-B) in 25 of 26 patients. Direct IF staining characterized by discrete speckled IgG deposits in the basal cell cytoplasm is associated with Ro(SS-A) antibodies and SCLE.


North Carolina tanning operators: hazard on the horizon? Previous small studies have demonstrated that operators of commercial tanning equipment may not be adequately trained. Most states have no training requirements for tanning operators. This study was designed to assess the medically relevant knowledge of cosmetic tanning salon operators and relate these to demographic variables. A written, anonymous questionnaire was distributed to 984 attendees of the first required operator training seminars conducted in North Carolina. Between July 1990 and June 1991, proprietors and their employees of the commercial tanning industry who attended these seminars were surveyed. No conference attendee refused to complete the questionnaire. Demographic information and responses to the medical information section of the questionnaire were scored by computer. Important findings included that 71% of surveyed operators had never received any training for their current position. Operators of cosmetic tanning equipment were often unaware of contraindications to tanning such as photosensitizing drugs and specific medical conditions. Few operators recognized methoxsalen (26%) or trisoralen (34%) or their respective proprietary names as contraindications to tanning. Operator knowledge was not related to their educational achievement, previous tanning salon experience, or prior tanning industry-sponsored training. Children younger than 10 years old were tanned by 2.6% of the operators. These data suggest that the public may be at risk for UV light-induced diseases and burns because of operator lack of knowledge.


Photosensitivity induced by fibric acid derivatives and its relation to photocontact dermatitis to ketoprofen. Photosensitivity reactions to fibric acid derivatives are not well understood and have been rarely reported. The aim of this study was to describe two cases of photosensitivity, one induced by fenofibrate and one by bezafibrate; to study the in vivo photosensitizing potential of these drugs; and to evaluate the possibility of cross-reactivity between fenofibrate and ketoprofen. Patch and photopatch tests with fibric acid derivatives and ketoprofen were performed in the patients, in 12 normal volunteers, and in 7 patients with photopatch-proven photocontact dermatitis to ketoprofen. Phototesting studies were performed both while the patients were taking the drugs and after withdrawal of them, as well as in a group of 18 hyperlipemic volunteers without history of photosensitivity who were taking therapeutic doses of fenofibrate or bezafibrate for 2 to 3 months. Positive photopatch test responses to ketoprofen and to fenofibrate were obtained only in the first patient, who also had a weaker positive ordinary patch test response to the latter. Five patients photosensitized to ketoprofen also had a positive patch test to fenofibrate. Phototesting studies were abnormal in both patients but normal in all volunteers. An association between systemic photosensitivity to fenofibrate and photocontact sensitivity to ketoprofen seems to exist. The structural similarities of these chemicals favor cross-reactivity.


The site of blister formation in dermatitis herpetiformis is within the lamina lucida. Because the initial neutrophilic infiltrate in dermatitis herpetiformis is within the dermal papillae, most investigators have assumed the vesicles occur in this same area. This was supported by electron microscopy studies. In 1983 Klein et al. refuted this concept, suggesting that vesicle formation was within the lamina lucida above the lamina densa. Despite this study, current literature continues to state that blister formation is below the lamina densa. Our purpose was to determine the ultrastructural site of blister formation in early and late vesicles of dermatitis herpetiformis. We evaluated eight biopsy specimens from four patients by immunomapping with antibodies to bullous pemphigoid antigen, laminin, type IV collagen, and epidermolysis bullosa acquisita antigen. In both early and late vesicles blister formation was found to be above the lamina densa in the lamina lucida. These findings are contrary to the commonly held concept that the blister in dermatitis herpetiformis is below the lamina densa and confirm the findings of Klein et al. that the site of blister formation in dermatitis herpetiformis is above the lamina densa within the lamina lucida.


Verification of a formula for determination of preexcision surgical margins from fixed-tissue melanoma specimens. Recently our group reported on the shrinkage of 199 malignant melanoma surgical-excision specimens. In that report, a multivariate analysis revealed that the age of the patient was the only factor that significantly affected the percentage shrinkage of a surgical specimen. In addition, a formula was presented that extrapolates the actual surgical margins (in vivo) from the (contracted) fixed-tissue pathology report measurement and the reported in vivo lesion diameter. The goals of this study are to verify that shrinkage of surgical specimens is approximately 20% and that the margin formula can be successfully applied to a different group of patients. Four hundred seven patients with malignant melanoma were prospectively enrolled to measure preexcision (outlined with ink) surgical margins, fixed-tissue (contracted) surgical margins, and overall specimen shrinkage. It is verified that overall shrinkage of cutaneous surgical specimens is approximately 20%. Surgical specimens from patients younger than 50 years of age have approximately 25% shrinkage. Those specimens from patients 50 to 59 years of age have approximately 20% shrinkage and those from patients 60 years of age or older have about 15% shrinkage. The surgical margins predicted by the margin formula were within +/- 3.5 mm of the actual measured surgical margin 86.5% of the time. The actual surgical margins (in vivo) of a malignant melanoma can be reasonably estimated from the fixed-tissue pathology measurement via the margin formula. The shrinkage of a surgical specimen is 15% to 25% depending on the patient's age.


Treatment of telangiectases and other benign vascular lesions with the 577 nm pulsed dye laser. This study was undertaken to evaluate the effectiveness and safety of the 577 nm pulsed dye laser in the treatment of various vascular lesions of the face. Our purpose was to make observations on the effects of different variables that could affect response. Ninety-two adults with telangiectases of the face were sequentially selected for treatment according to a protocol previously established. Evaluation consisted of visual inspection by two investigators, and before and after photographs at 2-months intervals. A few patients with other vascular lesions were also treated and reported. Ninety-one percent of the patients (84 of 92) showed good to excellent response after a single treatment. Recurrence occurred in 2%. Atrophy of the skin occurred in 2%. Venous lakes, pyogenic granulomas, and mucosal vascular malformations showed significant improvement. The 577 nm pulsed dye laser is effective and safe for vascular lesions of the face.


Topical treatment of Old World cutaneous leishmaniasis caused by Leishmania major: a double-blind control study. A controlled study of the efficacy of topical paromomycin sulfate (PR) and methylbenzethonium chloride (MBCl) in cutaneous leishmaniasis (CL) has not yet been performed. The therapeutic effect of an ointment containing 15% PR and either 12% or 5% MBCl (15/12 or 15/5 P-ointment) on patients suffering from Old World CL was examined in a randomized, double-blind, cross-over study. Thirty-nine patients with Old World CL caused by Leishmania major were treated topically, twice daily, for 10 to 20 days with 15/12 or 15/5 P-ointment and 10 to 20 days with a placebo ointment to achieve a total of 30 days of treatment in all groups. In the P-ointment-treated groups, 74.2% (29 of 39 patients) of the patients were cured versus 26.6% (4 of 15 patients) in the placebo-treated group. Little difference was found between the 15/12 and 15/5 P-ointment groups. In most of the patients treated with the active ingredients, total elimination of the parasites was achieved within the first 10 days of treatment.


Immunohistochemical examination of lichen nitidus suggests that it is not a localized papular variant of lichen planus. Lichen nitidus is believed, by some, to be a variant of lichen planus, and by others to be a distinct entity. We examined five cases of lichen nitidus with immunohistochemical reagents designed to characterize the dermal inflammatory infiltrate in an attempt to resolve the uncertainty. We stained formalin-fixed, paraffin-embedded tissue sections with the following antibodies: L26, A6, KP1, BerH2, OPD4, and HECA-452. The inflammatory infiltrate was 90% A6+, with few L26+ cells. In contrast to lichen planus, KP1+ macrophages were seen and fewer of the lymphocytes demonstrated HECA-452. Fifty percent to 80% of lymphocytes were OPD4 positive, similar to that usually seen in lichen planus. Rare Ki-1+ cells were seen in one case. We believe that the pattern of a mixed cellular infiltrate characterized by macrophages and a helper T cell response with few HECA-452+ cells is somewhat different from the pattern seen in lichen planus, wherein almost all of the cells are CD4+/HECA-452+ lymphocytes. This suggests a different immunologic pathogenesis.


Basaloid follicular hamartoma: solitary and multiple types. Multiple skin tumors often show autosomal dominant inheritance; solitary neoplasms are typically nonhereditary. The purpose of this study was to investigate a possible hereditary pattern in patients with multiple and solitary basaloid follicular hamartomas. Four new familial cases of multiple basaloid follicular hamartomas and 56 solitary nonhereditary examples were identified and their inheritance pattern recorded. Clinically, basaloid follicular hamartomas were typically 1 to 2 mm, smooth facial papules. Histologically, they were well-circumscribed lesions composed of anastomosing strands of squamoid and basaloid cells in a loose stroma. Horn cysts and pigmentation were common. No significant association with other cutaneous or internal disease was found. Basaloid follicular hamartoma, a unique benign follicular tumor, was often diagnosed previously as trichoepithelioma or basal cell carcinoma. It is another cutaneous neoplasm in which patients with multiple lesions show autosomal dominant inheritance, whereas solitary growths with identical clinical, microscopic, and biologic features are nonhereditary.


Surgical margins for excision of primary cutaneous squamous cell carcinoma. No guidelines for the margin of resection of cutaneous squamous cell carcinoma have been based on data measuring subclinical tumor extension, as have been formulated for basal cell carcinoma. Guidelines for appropriate margins of excision of primary cutaneous squamous cell carcinoma were formulated on the basis of a prospective study of subclinical microscopic tumor extension. Four millimeter margins were adequate for most squamous cell carcinomas. However, certain tumor characteristics were associated with a greater risk of subclinical tumor extension and included size of 2 cm or larger, histologic grade 2 or higher, invasion of the subcutaneous tissue, and location in high-risk areas. Minimal margins of excision of 4 mm around the clinical borders of the squamous cell carcinoma are proposed for all but the high-risk tumors, in which at least a 6 mm margin is recommended.


Thinning of the ozone layer: facts and consequences. The ozone layer is showing small but definite signs of depletion. Despite this, significantly increased UV radiation transmission at ground level has been found only in the Antarctic and Arctic regions. The potential for increased transmission of UV radiation will exist for the next several hundred years. Although little damage from increased UV radiation has occurred so far, the potential for long-term problems is great. The natural history of ozone and the causes and consequences of, and possible solutions to ozone depletion are examined in this article.


Psoriasis and human immunodeficiency virus infection. Psoriasis associated with human immunodeficiency virus (HIV) infection has been reported to be severe and perhaps associated with decreased survival. Our purpose was to document the natural history, response to therapy, and effect of psoriasis and its treatment on survival in HIV-infected patients with psoriasis. This was an observational cohort study of 50 persons with psoriasis and HIV infection followed up during a 2-year period. In one third of the patients the psoriasis appeared before 1978, the year when HIV seroconversion began in San Francisco (group I). In two thirds psoriasis developed after 1978 (group II). Group I had a lower mean age of onset (19 vs 36 years) and more commonly had a family history of psoriasis. Palmoplantar and inverse psoriasis were more common in group II. Severe psoriasis occurred in one fourth of this group (12 of 50 patients). The median survival in this group after diagnosis of acquired immunodeficiency syndrome (AIDS) was 19 months, which is comparable to the median survival for all AIDS patients diagnosed in San Francisco between 1984 and 1990. Psoriasis in the setting of HIV disease may be mild, moderate, or severe. Standard therapies and zidovudine are effective in management. Survival does not seem to be adversely affected by the presence of psoriasis or its therapy.


Differences in direct immunofluorescence staining patterns in epidermolysis bullosa acquisita and bullous pemphigoid. Both bullous pemphigoid (BP) and epidermolysis bullosa acquisita (EBA) are characterized by linear IgG deposits along the basement membrane zone (BMZ). Although these diseases can be distinguished by special tests, the staining pattern on direct immunofluorescence (DIF) is identical. The purpose of the present study was to reevaluate DIF as a diagnostic tool in differentiating EBA from BP. We performed DIF studies on biopsy specimens from eight consecutive patients with EBA and 18 consecutive patients with BP. In five of eight cases of EBA, C3 deposition was essentially absent. IgG was the predominant class of immunoglobulins in the deposits and was present along the BMZ in all eight cases. C3 was present in 17 of 18 cases of BP. IgG was the predominant immunoglobulin present in 15 of these 18. Patients with EBA are more likely to have linear IgG staining along the BMZ without concomitant C3 deposition than are patients with BP. This difference may be a function of the ability of the autoantibodies to fix complement.


Small-diameter malignant melanoma: a common diagnosis in New South Wales, Australia. The "ABCDE" guide developed at the New York University Medical Center and Harvard Medical School has proved useful in the detection of early malignant melanomas. This guide stipulates that melanomas usually are more than 6 mm in maximal diameter and are elevated. Our purpose was to determine whether these size criteria applied in Australia. The records of 1150 melanoma patients at the Sydney Melanoma Unit between June 1989 and September 1991 were reviewed. Almost one third of the 1150 melanomas (358) were 6 mm or less in maximal diameter, and the median thickness of these 358 melanomas was 0.8 mm. The "ABCDE" guide to the signs of early melanoma may have to be modified to include smaller diameter, clinically impalpable melanomas. There appears to be a close correlation between patient age at diagnosis and both lesion diameter and thickness. Because increases in diameter occurred more rapidly than increases in thickness, subtle increases in lesion diameter may provide a better clue to earlier diagnosis.


Hydrocortisone sensitivity: clinical features of fifty-nine cases. Hypersensitivity to topical steroids is becoming increasingly recognized. Our purpose was to establish factors associated with allergy to topical hydrocortisone. Data from 59 consecutive patients allergic to hydrocortisone were compared with 199 consecutive patients who were not allergic to hydrocortisone. Patients with stasis dermatitis and leg ulceration were significantly more likely to be allergic to hydrocortisone. In patients with hand eczema, in whom hydrocortisone sensitivity was less common, hydrocortisone was still a common allergen, occurring as frequently as wool alcohols and colophony. In four patients with atopic eczema, hydrocortisone was the only allergen. Duration of dermatitis was not important in determining the presence of hydrocortisone allergy. However, patients allergic to hydrocortisone were more likely to have multiple allergies when compared with control subjects. Allergy to topical hydrocortisone is associated with stasis dermatitis and multiple positive patch test reactions.


Perioral dermatitis in childhood.

Perioral dermatitis in childhood. Although perioral dermatitis has been well described in young women, little has been reported about this condition in children. The purpose of this study was to define more clearly the features of perioral dermatitis in childhood. Fourteen children with perioral dermatitis were assessed for clinical features, therapeutic response, and possible etiologic factors. Fourteen cases of perioral dermatitis were seen in 16 months, far exceeding the expected prevalence in childhood. Although the childhood variant shares many characteristics with the adult form, children often have periocular and perinasal lesions, as well as a higher relative incidence in boys. Mid- to high-potency topical corticosteroids were used in seven of the patients (50%) and likely contributed to the pathogenesis. All children responded rapidly to treatment. Perioral dermatitis in childhood, often iatrogenic, is more common than previously reported.


Unilateral laterothoracic exanthem in children: a new disease? We have examined 18 children with a similar laterothoracic exanthem that appears to represent a distinct entity. Our purpose was to describe the characteristic signs and clinical course of this eruption and its epidemiology data. We observed the clinical course of the eruption in each child. The eruption has characteristic features. It occurs in a homogeneous age group (mean 23.3 months). It is initially unilateral and localized close to the axilla. The basic lesion is eczematous or scarlatiniform. The eruption evolves in two phases: it spreads centrifugally during the first 8 days and becomes more widespread on the tenth to fifteenth days, with predominant involvement on the half of the body initially affected. The lesions resolve spontaneously within 4 weeks. The long-term course is uneventful. The similarity of the cases suggests the existence of a new clinical entity. Many features favor a viral origin.


Pigmented Spitz nevi: improvement of the diagnostic accuracy by epiluminescence microscopy. Pigmented Spitz nevi have distinct clinical features but often may be difficult to differentiate from malignant melanoma by clinical criteria. The purpose of this study was to use a new noninvasive diagnostic approach to improve the clinical diagnosis of Spitz nevi. Epiluminescence microscopy (ELM) is a new, noninvasive technique for which criteria for the diagnosis of melanocytic tumors, benign and malignant, recently have been established. These criteria were tested in an investigation of 54 pigmented Spitz nevi. With ELM the accuracy of clinical diagnosis of pigmented Spitz nevi improved from 56% (clinical) to 93% (ELM). Our findings suggest that ELM criteria are useful to improve the accuracy of clinical diagnosis of Spitz nevi.


Atypical melanocytic nevi. Clinical and histopathologic predictors of residual tumor at reexcision. The appropriate method for surgical management of melanocytic lesions with disordered architecture and melanocytic atypia (formerly dysplastic nevi) has been controversial. Physicians often reexcise these lesions after primary removal because of their potential relation to malignant melanoma. The outcomes of these reexcisions and the original biopsy specimens have not been previously examined. The purpose of this study was to examine reexcision specimens and their respective original specimens to determine whether there were any characteristics predictive of the presence of residual nevus cells (RNCs) on reexcision. One hundred eighty-nine reexcision specimens of atypical melanocytic lesions were evaluated for this study. The original specimens were examined for specific histopathologic features without knowledge of the findings on reexcision. Clinical characteristics were also examined. Of the 189 reexcision specimens, 47 (24.9%) contained RNCs. The proportion of specimens with RNC on reexcision was significantly greater if the original lesion was removed by punch biopsy rather than by shave or elliptical excision (38.3% vs 22.0% vs 10.5%, respectively; p < 0.03). Lesions located on the chest had a higher likelihood of RNCs than those on the back or leg (52.2% vs 21.7%; p = 0.009; 52.2% vs 9.7%, p < 0.002, respectively). Mean age was greater in those with RNCs at reexcision than those without (43.6 vs 37.9 years, respectively; p < 0.0001). The proportion of specimens with RNCs at reexcision was greater in those that had both lateral margins involved than in those that had nevus cells in either one or neither of the lateral margins in the original biopsy specimens (39.7% vs 24.0% vs 7.8%, respectively; p = 0.0005). One of the 189 reexcision specimens (0.5%) contained melanoma, although the original histopathologic diagnosis was an atypical melanocytic nevus. We identified several clinical and histopathologic factors that are strongly associated with the presence of RNCs on reexcision.


Role of foods in the pathogenesis of chronic paronychia. Chronic paronychia is a condition that is pathologically characterized by spongiotic inflammation; it can be exacerbated by various and concomitant factors. The aim of this study was to assess whether chronic paronychia in food handlers may have clinical, pathologic, and immunohistochemical similarities with immediate contact dermatitis caused by foods. Twenty food handlers affected by chronic paronychia were submitted to patch tests with the fresh foods that were suspected of being the cause of the dermatitis. Nine patients had a positive reaction to a 20-minute open patch test with fresh foods applied on the proximal nailfold. In two patients the pathologic study of the positive open patch test site showed acanthosis, exocytosis, and spongiosis of the epidermis and the presence of an inflammatory lymphocytic infiltrate in the dermis. Our results confirm the view that an immediate hypersensitivity reaction to foods can be responsible for some cases of chronic paronychia in food handlers.


Malignant tumors in patients with psoriasis. There is strong epidemiologic evidence that psoriasis treatments may cause nonmelanoma skin cancer and possibly other types of cancer. This study from Denmark reports the cancer incidence in 6910 patients with psoriasis discharged from the hospital from 1977 through 1987. Patients were identified in the National Hospital Discharge Register and information on cases of cancer was obtained through the files of the Danish Cancer Registry; observed figures were compared with those expected on the basis of cancer incidence rates for the national population. A 2.5-fold increased risk was observed for nonmelanoma skin cancer in men and women, with no preponderance of any specific histologic subtype of cancer. In addition, excesses were seen of lung cancer in men (relative risk [RR] = 1.4) and women (RR = 1.6), of cancer of the larynx and pharynx in men (RR = 2.8 and 3.9), and of colon and kidney cancer in women (RR = 1.6 and 2.3). The effect of cigarette smoking on the risk for noncutaneous cancer could not be assessed in this study; however, antipsoriatic treatment such as ionizing radiation and oral arsenicals must be considered as a possible cause of colon cancer, which has been observed in excess in two other studies of psoriatic patients.


The effect of intralesional 5-fluorouracil therapeutic implant (MPI 5003) for treatment of basal cell carcinoma. Basal cell carcinomas (BCCs) are usually treated with ablative procedures. A nonsurgical treatment alternative would be of value in selected patients. We evaluated the safety and efficacy of a new preparation for intralesional sustained-release chemotherapy with MPI 5003, 5-Fluorouracil Therapeutic Implant, for treatment of BCCs. Two doses of intralesional MPI 5003 (0.25 and 0.5 ml) were compared in a double-blind study of 20 patients with biopsy-proven BCC. One BCC per patient was treated weekly for up to 6 weeks and followed up monthly for 3 months until excisional biopsy for histologic examination. Before excision the cosmetic appearance of the test site was graded. Eighty percent of 10 BCCs treated with 0.5 ml of MPI 5003 had histologically confirmed cures as compared with 60% of 10 tumors treated with the lower dose (0.25 ml). Cosmetic assessments before excision were typically good to excellent. No systemic side effects occurred. Results indicate the potential of MPI 5003 for targeted local chemotherapy for BCC.


Extracorporeal photopheresis for the treatment of cutaneous T-cell lymphoma. Many regimens are used for cutaneous T-cell lymphoma (CTCL), but with advanced disease response rates and patient survival are not adequate with any current therapy. Recently extracorporeal photochemotherapy (ECP) was proposed as an alternative therapy. Our purpose is to present the results of ECP in patients with CTCL refractory to other treatments. Patients with CTCL received ECP at 3- to 5-week intervals for at least 6 months. All patients except one were in stage T2 (patch/plaque) or higher. Eight patients had extracutaneous disease involving lymph nodes (six patients), bone marrow (five), or Sézary cells (six). The interval between initial symptoms and diagnosis was 5.9 +/- 1.9 years (mean +/- standard error of the mean) and the interval between diagnosis and ECP was 2.2 +/- 0.4 years. A complete response (disappearance of all lesions) was obtained in five patients (25%) and a partial response (disappearance of at least 50% of lesions) in six patients (30%). Four patients (20%) showed stabilization of their disease and five progressed (25%). The only variable that predicted responders versus nonresponders was the number of ECP sessions (p < 0.05 by multivariate logistic regression). In contrast, no separate beneficial effect of adjunctive chemotherapy (p > 0.5) or electron beam therapy (p > 0.1) was found. Long-term ECP may be an effective alternative treatment for CTCL refractory to other therapies and is likely to be even more useful when combined with other modalities.


Carbon dioxide laser treatment of actinic cheilitis. Clinicohistopathologic correlation to determine the optimal depth of destruction. The carbon dioxide laser is an effective modality for the treatment of actinic cheilitis, but the number of passes required is unknown. After each pass different visual tissue qualities are observed. Our purpose was to identify and characterize histologically the tissue zones seen after laser impact and thereby to determine the optimal depth of destruction of diseased tissue. Twenty-three biopsy specimens from 14 patients were obtained from zones of different tissue qualities after one and three passes with the laser. Specimens were histologically examined for the presence or absence of diseased epithelium and degree of thermal necrosis. Complete destruction of the epithelial layer was observed in all specimens irrespective of the number of laser passes. The amount of dermal homogenization increased with multiple passes. Treatment to the first or second surgical zone is effective for actinic cheilitis.


An analysis of interobserver recognition of the histopathologic features of dysplastic nevi from a mixed group of nevomelanocytic lesions. The diagnostic criteria for the histopathologic recognition of the dysplastic nevus are defined, but difficult to apply in practice. However, the use of skin biopsy is on the increase to search for this nevus because of a possible role in melanomagenesis. The aim was to determine the degree of observer reproducibility in the detection of histologic nevomelanocytic dysplasia as measured across multiple observers and to test whether each observer was precise over a wide sample population. A second aim was to gain some measure of the threshold a person has for such lesions. Histologic specimens from 50 coded nevomelanocytic tumors, which included a group of dysplastic nevi, were independently read by five observers in a blinded fashion. At study completion, the same 50 cases were read again by a melanoma reference pathologist and results analyzed by Cohen's kappa to assess agreement and interobserver variation. Corrected rates of agreement for dysplastic nevi ranged from 0.32 to 0.71. Continued study and experience are required for precision and reproducibility in the histologic recognition of dysplastic nevi.


Rothmund-Thomson syndrome: review of the world literature. Rothmund-Thomson syndrome is a rare, inherited disorder characterized by poikilodermatous skin changes that appear in infancy. The inheritance is autosomal recessive. Patients exhibit variable features including skeletal abnormalities, juvenile cataracts, and a higher than expected incidence of malignancy. This extensive review of the world literature clarifies aspects of the inheritance, incidence of characteristic features, and malignant potential of this disease. Insight into its origin is provided through a review of the clinical and in vitro studies of endocrine function and possible DNA repair abnormalities.


Chum salmon (Oncorhynchus keta) stanniocalcin inhibits in vitro intestinal calcium uptake in Atlantic cod (Gadus morhua). Chum salmon (oncorhynchus keta) stanniocalcin was purified, partially identified and tested for bioactivity in an assay on the intestinal calcium uptake in a marine teleost (Gadus morhua). Basic ethanol extraction, ion exchange chromatography, gel filtration and reverse-phase high-performance liquid chromatography resulted in the isolation of a homogeneous glycoprotein that appears as a 46-kDa product under nonreducing conditions and as a 23-kDa product under reducing conditions after sodium dodecylsulphate-polyacrylamide gel electrophoresis. The glycoprotein is likely to be a homodimer composed of two subunits of 23 kDa each. Further characterization indicates homology to Australian eel, sockeye salmon, coho salmon and rainbow trout stanniocalcin, and the glycoprotein is thus concluded to be stanniocalcin. Stanniocalcin-like immunoreactivity was demonstrated in the corpuscles of Stannius of the Atlantic cod, with a specific antiserum raised against purified chum salmon stanniocalcin. The physiological importance and the biological activity of chum salmon stanniocalcin was tested by evaluating its effect on intestinal calcium uptake by the Atlantic cod in vitro. The intestine was perfused, both vascularly and through the intestinal lumen, and the calcium mucosa-to-serosa flux was measured using 45Ca2+ as a tracer. Stanniocalcin decreased the intestinal calcium uptake in a dose-related manner by 13.5% and 22.4% at doses of 2.2 and 10.9 nM stanniocalcin, respectively. The results establish the intestine as a target organ for stanniocalcin in marine teleosts.


Sodium-dependent short-circuit current across the yolk sac membrane during embryonic development in normal and shell-less cultured chicks. The transepithelial electrical characteristics of the isolated yolk sac membrane of normal in ovo or shell-less cultured chick embryos were investigated. In normal chicks the potential difference (blood side positive relative to yolk side) and short-circuit current of the membrane increased during development. Ouabain (10(-4) M) on the blood side (basolateral side, serosal side) significantly decreased potential difference and short-circuit current but was without effect on the yolk side (brush border side, mucosal side). Substitution of choline for Na+ in the bathing solutions abolished the potential difference and the short-circuit current; when Na+ replaced choline this effect was reversed. Amiloride added to both sides of the yolk sac membrane had no effect on potential difference or short-circuit current. Injection of aldosterone (50 micrograms) and T3 (10 microM) into yolk did not induce amiloride sensitivity. The short-circuit current was not altered by addition of either glucose or alanine to the bath. The short-circuit current of the yolk sac membrane of shell-less cultured embryos was significantly lower than that of normal controls. Addition of Ca2+ to the serosal bathing medium did not reverse the foregoing condition, but decreased the short-circuit current. It is concluded that the yolk sac short-circuit current is Na+ dependent and increases with developmental age in the chick embryo.


Seasonal changes in the activation of crossbridge motions of isolated thick filament from Limulus striated muscle. In dynamic light scattering, measurements of the intensity-intensity time correlation function from a suspension of rod-like particles of length L could reveal dynamical information related to translational and internal motions of those particles. For a suspension of thick filaments isolated from the myosin-regulated, striated muscles of Limulus at KL greater than 1 (where K is the scattering vector), the average characteristic linewidth (gamma) increased with the addition of Ca2+ or with the depletion of ATP. The increase in the gamma with the addition of Ca2+ could be due to the presence of energy-requiring, high-frequency motions of the crossbridges activated by Ca2+. The increase in gamma which occurred with the depletion of ATP was assumed to be mainly due to the thermal motions of the crossbridges after they had moved radially away from the filament backbone. The percentage increase in gamma following the addition of Ca2+ was found to be seasonal, i.e., values of gamma obtained from thick filaments isolated between the middle of June and the middle of September were smaller than those obtained during the rest of the year. The effect of temperature on the percentage increase in gamma was also different. The increase showed a maximum at about 35 degrees C during the summer and at about 25 degrees C at other times. However, the percentage increase in gamma developed under ATP-depleted conditions showed no temperature-related maximum. The number of bound Ca2+ per myosin molecule was 1 during the summer and 2 at other times.


Effect of steroid hormones on serotonin, norepinephrine and epinephrine contents in the pineal-paraphyseal complex of the soft-shelled turtle (Lissemys punctata punctata). Steroids (testosterone, oestrogen, progesterone, corticosterone, dexamethasone and deoxycorticosterone) were administered intramuscularly (0.1 mg.100 g bw-1) on seven consecutive days to juvenile male soft-shelled turtles. Serotonin, norepinephrine and epinephrine contents of the pineal-paraphyseal complex were measured spectrofluorometrically 24 h after the last injection. Testosterone and oestrogen decreased serotonin, norepinephrine and epinephrine levels. Progesterone treatment resulted in an increase of serotonin level and a fall in norepinephrine and epinephrine levels. Corticosterone treatment caused an increase of serotonin level and a decrease of norepinephrine and epinephrine levels. Dexamethasone failed to alter serotonin content, increased norepinephrine and decreased epinephrine levels. Deoxycorticosterone decreased serotonin and elevated epinephrine content.


Relationship between a long-term treatment of 2-mercaptoethanol and protein metabolism in the ageing rat. Female RLEF1/Lati rats were chronically treated with 2-mercaptoethanol in a dose of 13 micrograms.100 g bw-1.day-1 dissolved in drinking water. During a 48-h experiment 15N-labelled glycine was given orally in a dose of 5 mg 15N.kg bw-1 and urine samples were collected and analysed by an emission spectrometric isotope method. Protein synthesis and nitrogen excretion rate constants were calculated according to the three-pool model, and 3-methylhistidine excretion rates were also determined. 2-Mercaptoethanol appears to influence protein metabolism; however, the slower rates of protein synthesis proved to be apparent in almost all groups of treated rats. Protein synthesis and nitrogen excretion rate constants have exceptionally high values in 2-year-old rats, possibly explained by the occurrence of hypercompensation mechanisms in old age. These were reflected by the excretion rates of 3-methylhistidine which were reduced as a result of sulphhydryl group interactions in age-dependent cellular metabolic changes.


Digestive tract morphology and digestion in the wombats (Marsupialia: Vombatidae). Wombats consume grasses and sedges which are often highly fibrous. The morphology of the digestive tract and the sequence of digestion were studied in two species of wombats from contrasting habitats: Vombatus ursinus from mesic habitats and Lasiorhinus latifrons from xeric regions. Studies were performed on wild wombats consuming their natural winter diets, and on captive wombats fed a high-fibre pelleted straw diet. Vombatus had a shorter digestive tract (9.2 vs 12.5 times body length) of greater capacity (wet contents 17.9 vs 13.7% body weight) than Lasiorhinus. The most capacious region of the digestive tract was the proximal colon (62-79% of contents). The proportional length and surface area of the proximal colon were greater in Vombatus, but those of the distal colon were greater in Lasiorhinus. These digestive morphologies may reflect adaptations for greater capacity and longer retention of digesta in Vombatus, but greater absorption and lower faecal water loss in Lasiorhinus. Apparent digestion along the digestive tract was estimated by reference to lignin. The proximal colon was the principal site of fibre and dry matter digestion, whereas nitrogen was mainly digested in the small intestine. Depot fats in captive wombats were highly unsaturated and reflected those in the diet. Therefore, lipids, proteins and soluble carbohydrates in the plant cell contents were digested and absorbed in the stomach and small intestine. Conversely, dietary fibre was probably retained and digested by microbial fermentation along the proximal colon.


Hindgut fermentation in the wombats: two marsupial grazers. The wombats Vombatus ursinus and Lasiorhinus latifrons have a capacious proximal colon with only a vestigial caecum. The pattern of microbial fermentation in the hindgut of both species was studied in captive animals fed a pelleted straw diet and in wild wombats feeding on their natural winter diets. Digesta pH was low in the stomach but near neutrality along the hindgut, indicating effective absorption and/or buffering of the colonic contents. Initial proportions and production rates of short chain fatty acids in vitro reflected the fermentation of plant cell walls. Proportions of isobutyrate, isovalerate and n-valerate increased towards the distal colon indicating proteolysis and subsequent fermentation of amino acids. The low ammonia content of digesta fluid suggested that ammonia released from these amino acids was absorbed and utilized by the wombats and their gut microbes. Wild wombats had higher concentrations and production rates of short chain fatty acids than captive animals, which was consistent with the higher apparent digestibility of their natural diet. The energy from short chain fatty acids in captive animals was 30-33% of digestible intake. Energy intakes were low and similar to resting metabolic rates estimated for marsupials. Actual resting metabolic rates of the wombats are probably lower than these estimates, and the proportion of energy derived from fermentation substantially higher than the 53-61% estimated in wild wombats. The energy from fermentation clearly enables wombats to utilize diets high in fibre.


Contrast enhanced area of posterior pituitary gland in early dynamic MRI exceeds hyperintense area on T1-weighted images. Seventeen normal pituitary glands were studied by midline sagittal (and in one case axial) dynamic MRI before and immediately after injection of Gd-DTPA, using spin-echo sequences with a short repetition time. Images were obtained at 1 min intervals for 6 min at 1.5 T. A well-defined focal area with marked enhancement was seen in the posterior portion of the pituitary gland on the first image after injection of Gd-DTPA. The size of the early enhancing area in the posterior pituitary (EEPP) was compared with the high signal of the posterior pituitary (HSPP) on the precontrast image. The EEPP was larger than the HSPP in 10 cases (59%). The two were equal in size in seven cases (41%). The EEPP was anteriorly convex in 11 cases (65%), whereas HSPP was anteriorly convex in 4 cases (24%). We believe that EEPP closely represents the real extent of the posterior lobe. Our results support the hypothesis that HSPP may involve only a portion of the posterior pituitary.


Intravascular thrombosis as a possible cause of transient cortical brain lesions: CT and MRI. Cortical brain lesions were identified on MRI and CT in 14 patients with a variety of diseases. Each of these patients developed neurologic symptoms, the most prominent of which were seizures, depressed mental status, and blurred vision or cortical blindness. Both the imaging and the neurologic abnormalities resolved spontaneously within a period ranging from 5 to 30 days. Due to location and evolution of the lesions over time we hypothesize that they are secondary to small cortical venous thromboses.


Degeneration of the posterior columns of the spinal cord: postmortem MRI and histopathology. Postmortem MR images of two cases of posterior column degeneration were correlated with histopathological findings. The abnormal MR findings were volume loss and high signal intensity of the posterior columns associated with mild deformity of the dorsal surface of the spinal cord, corresponding to tract degeneration on histopathological examination. These results strongly suggest that further development of MR technique will permit in vivo detection of posterior column degeneration.


Glioependymal cysts: CT and MR findings. Four patients with intracranial glioependymal cysts were evaluated in our institution in the last 7 years. All underwent surgical drainage and biopsy of the cyst wall. Cranial CT revealed a uniformly hypodense lesion with no contrast enhancement in all cases. Magnetic resonance imaging studies revealed a well defined cyst that was isointense to CSF on T1-weighted images and iso- or mildly hyperintense to CSF on proton density and T2-weighted images. In one case, a fluid-fluid level was demonstrated within the cavity, indicating the presence of fluid with a high protein content. A diagnosis of glioependymal cysts can be suggested based on CSF-like intensity patterns on T1-weighted images and iso- or mild hyperintensity on T2-weighted images.


Use of fluid attenuated inversion recovery (FLAIR) pulse sequences in MRI of the brain. Fluid attenuated inversion recovery pulse sequences with a long echo time (TE) have been used to image the brain in one volunteer and four patients. The long inversion time used with this sequence suppresses the signal from CSF and the long TE produces very heavy T2 weighting. The marked reduction in flow artefact from CSF and the high T2 weighting enabled anatomical detail to be seen within the brain stem and produced high lesion contrast in areas close to CSF. Lesions were demonstrated with greater conspicuity than with conventional T2-weighted sequences in patients with cerebral infarction, low grade astrocytoma, and diplegia.


Midline anterior atlas clefts: CT findings. Anterior atlas clefts (AACs) are rare developmental variants that may mimic fractures. Due to the potential severe implications of craniocervical junction trauma, expeditious differentiation between a Jefferson burst fracture and a congenital cleft is essential in trauma patients. Three cases of AAC are presented. Two cases demonstrated incidental AACs; the third case was associated with a Jefferson burst injury. Computed tomography is most helpful in evaluating the integrity of the atlas; however, plain radiography or pluridirectional tomography are best for evaluating displacement of the lateral masses of C1 in relation to C2.


Evaluation of soft palate function with MRI: application to the cleft palate patient. Magnetic resonance imaging was employed to evaluate soft palate function in four normal volunteers and four patients with surgically repaired cleft palate, using a GE Signa clinical scanner at 1.5 T and a custom designed receive coil with a sensitivity profile encompassing from the nasopharynx to the larynx. Midsagittal images were obtained using spoiled gradient recalled acquisition at steady state while the subject phonated the following sounds: (a) MMM, (b) SSS, (c) DAH, and (d) EEE. An image at rest with normal breathing was also obtained. The soft palate and its relationship to the airway and the posterior pharyngeal wall were clearly visualized in all cases. Phonation of the prescribed sounds demonstrated the normal range of soft palate motion. The images also depicted the ability of the soft palate to divert airflow to the nasopharynx. Interpretation of functional MRI may be of value in evaluation of surgical results, guidance of speech therapy, and surgical planning in the cleft palate patient. This noninvasive alternative to conventional methods of visualization provides advantages in resolution, repeatability, and patient comfort.


The benign fibroosseous lesion: its association with paranasal sinus mucoceles and its MR appearance. Although fibrous dysplasia and ossifying fibroma of the facial bones may, with some difficulty, be distinguishable pathologically, they are inseparable radiographically. Based on a study of 30 patients, there was no good or reliable imaging correlation with the histology and the degree of ossification or the bone(s) involved. Therefore, "benign fibroosseous lesion" has been proposed by several noted bone authorities as the term for these entities. Eleven patients had MRI and the overall signal intensities were low on both T1-weighted and T2-weighted sequences. Areas of high signal intensity on T2-weighted imaging correlated with either cysts within the lesion or the presence of mucocele, especially in the frontoethmoid region. Four such mucoceles are presented. The coexistence of mucoceles and benign fibroosseous lesions may be more common than previously reported. It is both realistic and appropriate for the radiologist to diagnose these entities as benign fibroosseous lesions and leave the final histologic diagnosis to the pathologist who can diagnose most such cases, albeit with some difficulty. Sites of high signal intensity on T2-weighted imaging in the frontoethmoid area should raise the possibility of a coexistent mucocele.


Airway obstruction by right aortic arch with right-sided patent ductus arteriosus: demonstration by MRI. An unusual cause of airway obstruction was demonstrated by MRI in two infants with congenital heart disease. The two infants experienced airway obstruction caused by a right aortic arch with right-sided patent ductus arteriosus. The diagnosis was established by MRI prior to surgery; angiography did not demonstrate the critical relationship between the large ductus and the airway. Axial, sagittal, and coronal MRI displayed the right arch, dilated ductus, and the compression of the proximal right bronchus and distal trachea by the ductus. Surgical findings confirmed the MR diagnosis. Thus, MRI can be used to localize the site of airway obstruction and to demonstrate unusual types of vascular anomalies.


Anomalous left brachiocephalic vein: CT findings. Eight cases of anomalous position of the left brachiocephalic vein were demonstrated by CT. Six coursed downward lateral to and below the aortic arch to enter the superior vena cava (SVC). Two cases were double left brachiocephalic veins. The superior branch was in the normal position, but the inferior vessel coursed below the aortic arch. Most of these subaortic left brachiocephalic veins enter the SVC at the same level or caudal to the azygous arch. Only two cases were associated with congenital heart disease. This anomalously positioned vessel is asymptomatic but must be distinguished from the pulmonary artery and persistent left SVC, especially when open heart surgery for cardiac malformations is being considered.


CT findings in "pseudoalveolar" sarcoidosis. To determine the specific high resolution CT (HRCT) features for "pseudoalveolar" sarcoidosis, we reviewed HRCT of 10 patients with pathologically proven sarcoidosis. On HRCT the lesions of pseudoalveolar sarcoidosis were shown as homogeneous or inhomogeneous opacities 1-4 cm in diameter located either along the bronchovascular bundles or in the lung periphery adjacent to the pleural surface. The margin was irregular, and numerous nodules 1-2 mm in diameter were observed in the surrounding lung. Air bronchograms were observed in 6 patients. In addition to these lesions, other CT abnormalities such as nodules, groundglass opacities, thickened bronchovascular bundles, and interlobular septa were found in all 10 cases. Good response of pseudoalveolar sarcoid lesions to administration of corticosteroid was observed in all three cases in which follow-up CT was available.


Pseudoaneurysms at aortic cannulation site after coronary artery bypass graft: MR findings. Pseudoaneurysm at the aortic cannulation site is a rare but potentially fatal complication of coronary artery bypass surgery. We present two cases in which MRI provided significant information regarding the anatomy and extent of a pseudoaneurysm. In one case both spin-echo imaging and cine MRI with and without gradient moment nulling (flow compensation) were used. The absence of gradient moment nulling in cine MRI provides additional contrast between flowing and static blood. This contrast may complement conventional cine images with gradient moment nulling, providing further information.


CT evaluation of chronic thromboembolic pulmonary hypertension. Eight patients with chronic thromboembolic pulmonary hypertension (CTPH) that had been demonstrated by perfusion lung scan, pulmonary arteriography, and right heart catheterization had their pulmonary circulation evaluated by CT. Eight subjects without lung pathology were also studied for comparison. High resolution CT from apex to base with 1 cm thick sections after intravenous injection of contrast medium was performed in each individual. Emboli lodged in main pulmonary arteries on arteriography were regularly shown by CT, whereas those in segmental or smaller arteries were not detected. Diameters of the main pulmonary arteries measured on CT correlated with systolic pulmonary artery pressure (p < 0.001). The ratio between diameters of segmental arteries and the corresponding bronchi (A/B ratio) on CT was > 1 in 72 of 144 examined pulmonary segments (18 segments for each patient) in patients with CTPH. The ratio was > 1 in only 10 of 144 examined segments in normal control subjects. Dilatation of bronchial arteries was present in four of eight patients with CTPH. The parenchymal density in patients with CTPH was significantly higher in the axial than in the middle or peripheral lung compartments. In conclusion, CT may help with the diagnosis of CTPH by detecting thrombi of main arteries and by showing characteristic findings; moreover, it is accurate in estimating pulmonary arterial pressure secondary to thromboembolic obstruction.