Plastic bronchitis; a serious complication of the Fontan operation.

Plastic bronchitis is characterised by the formation of large bronchial casts, which develop in the tracheobronchial tree and can cause airway obstruction. It has been increasingly encountered in more recent years as a serious complication of the Fontan operation with a reported mortality of up to 50% [Am. J. Respir. Crit. Care Med. 155 (1997) 364]. We report a case of a 4-year-old girl with Fontan circulation who developed plastic bronchitis and was successfully treated.

Acute pancreatitis in patients with end-stage renal disease without transplantation.

Acute pancreatitis is infrequently described in patients with end-stage renal disease (ESRD) who have not undergone transplantation. We observed 35 attacks of acute pancreatitis in 23 of 1001 patients with ESRD and one additional patient with irreversible acute renal failure, during a ten-year period. Pancreatitis occurred more frequently in association with peritoneal dialysis than with hemodialysis. Four patients died of complications related to a pancreatic pseudocyst, and a fifth died from hemorrhagic pancreatitis. The ten-year incidence of pancreatitis was 2.3% and the overall mortality was 20.8% in patients with ESRD treated without transplantation. We conclude that clinically evident acute pancreatitis occurs more often than has been previously recognized in patients with ESRD who have not undergone transplantation and, particularly, in those patients managed with peritoneal dialysis.

Somatic neurons in the brainstem and neocortex projecting to the external nucleus of the inferior colliculus: an anatomical study in the opossum.

Some brainstem and neocortical neurons projecting to the external nucleus of the inferior colliculus were identified by retrograde axonal transport of horseradish peroxidase (HRP). Large pressure injections of HRP were used to define the population of cells in the dorsal column and trigeminal nuclei projecting to the entire inferior colliculus. Subsequently, tiny injections of HRP were delivered electrophoretically to various parts of the external nucleus using micropipettes. In each case the electrophoretic placements were made in sites identified as somatic by their response to foot shock or manual stimulation of the body. Receptive fields were found to be large and almost always bilaterally symmetric. Areas excitable by stimulation of the upper body were often found adjacent to areas excitable by stimulation of the lower body, tail, or, rarely, the face and head. In general, sites in the external nucleus which were identified by their responsiveness to stimulation of the body were not responsive to click stimuli. No topographic representation of the body was evident. After small electrophoretic injections of HRP absolutely restricted to the external nucleus, HRP-filled neurons were found bilaterally in the nucleus gracilis, nucleus Bischoff, (the midline and tail representation of the dorsal column nuclei), nucleus cuneatus, and nucleus trigeminalis, subnucleus caudalis. Ipsilateral neocortical cellular filling was found primarily in a continuous strip along the caudal and inferior margin of the parietotemporal cortex, in the area corresponding to SMII (Pubols, '77). Rarely, filled cells were found in the parietal area corresponding to SMI and in the temporal pole. In sum, small somatic-activated loci of the external nucleus receive bilateral, topographically convergent projections from hindbrain somatosensory structures and from the SMII cortex.

An anatomical study of some somesthetic afferents to the intercollicular terminal zone of the midbrain of the opossum.

Following lesions of the dorsal column nuclei, spinal cord and sensorimotor cortex, anterograde degeneration was traced to a common target in the central midbrain; the intercollicular terminal zone. Although not all the midbrain projections of the three pathways are contained within this zone, it receives overlapping projections from each of the three body-related somesthetic pathways studied. The intercollicular terminal zone covers the entirety of the external nucleus of the inferior colliculus and the intercollicular nucleus of Mehler, spilling over into adjacent parts of the central gray and deep layers of the superior colliculus. Little evidence of somatotopy in the somesthetic projections was disclosed, and bilateral input was found in each experimental case, regardless of the type of lesion. Golgi-stained material was examined to explore the basis of the extensiveness of the terminal zone. These materials showed that the dendritic spread of neurons in the external nucleus of the inferior colliculus and the intercollicular nucleus, taken together, covers the entirety of the intercollicular terminal zone. That is, the dendrites invade the same portions of the central gray and deep layers of the superior colliculus which are covered by the terminal field. We conclude that a tripartite division of the sensory midbrain may be justified: with the somesthetic modality being represented anatomically in a fashion at least roughly analogous to that of vision and audition.

The inferior olivary nucleus of the opossum (Didelphis marsupialis virginiana), its organization and connections.

Although the inferior olivary nucleus of the opossum is small, sections stained either for Nissl substance, normal axons or cholinesterase activity reveal distinct medial, dorsal and principal nuclei. The medial nucleus contains three major subdivisions (labelled a, b, c after Bowman and Sladek, '73) and a group of neurons which is comparable to the cap of Kooy. In contrast to the cat and monkey, the major portion of the "medial" nucleus (subgroup a) lies lateral to the principal nucleus in rostral sections. The dorsal nucleus can also be subdivided, as can the principal nucleus which contains distinct dorsal and ventral lamellae. A small area is identified which based on position and connections may conform to the dorsal medial cell group. The experimental portion of the study provides evidence for an olivary projection from the motor-sensory cortex and a massive input from the midbrain (red nucleus, pretectum, midbrain tegmentum). In addition, the opossum inferior olive receives fibers from the deep cerebellar nuclei (cerebellar feedback loops), the spinal cord and the dorsal column nuclei. Of particular interest is the finding that fibers from the nucleus cuneatus and nucleus gracilis have distinctly different olivary targets and that those from the nucleus gracilis, but not the cuneate nucleus, overlap (in part, at least) with the direct spinal fibers. Other examples of overlapping fields of terminal degeneration are present and are discussed. In general our results reveal that although certain relationships between the nuclear divisions are different, the opossum olive conforms well to that of placental mammals and provides a basic mammalian model for future experimental electron microscopic and physiological studies.

Two sibs with partial trisomy 2q.

We report on two sibs with facial anomalies and developmental delay. Partial trisomy 2q was detected only after parental chromosome studies showed the father to carry a balanced interchromosomal insertion of 2 (q24.3-q32.1) into 5q.

Double labelling of neuronal somata by [3H]uridine and horseradish peroxidase: a technique to demonstrate two-stage connections with the light microscope.

A new technique is described that may demonstrate two-stage connection at the light microscopic level. Anterograde transneuronal transport of [3H]uridine is used in conjunction with retrograde transport of horseradish peroxidase (HRP). The two compounds are injected separately into different brain regions. Under conditions of proper controls, neuron somata that are double labelled are interpreted as receiving an afferent projection from the region injected with [3H]uridine and sending an efferent projection to the region injected with HRP. Thus, the technique can demonstrate two-stage connections in the nervous system.

A subcortical pathway links sensory and limbic systems of the forebrain.

The subcortical afferents and cortical projections of the lateral dorsal nucleus of the thalamus were investigated using anterograde and retrograde axonal transport of horseradish peroxidase (HRP). The lateral dorsal nucleus receives afferent projections from several nuclei of the pretectal complex, and sends efferent projections to several subdivisions of limbic cortex. These connections constitute a two stage pathway that could convey visual and somatosensory information to the limbic system.

Rabies and canine distemper in an arctic fox population in Alaska.

Two oil field workers were attacked by a rabid arctic fox (Alopex lagopus) in the Prudhoe Bay oil field (Alaska, USA) prompting officials to reduce the local fox population. Ninety-nine foxes were killed during winter 1994. We tested foxes for prevalence of rabies and canine distemper. Exposure to rabies was detected in five of 99 foxes. Of the five, only one fox had rabies virus in neural tissue as determined by the direct fluorescent antibody test. The other four foxes had been exposed to rabies, but had apparently produced antibodies and did not have an active infection. No evidence of canine distemper was detected as determined by the absence of distemper antibodies in serum and distemper virus in neural tissue.

Transdermal fentanyl in the hospice: a survey of rescue dosing and pain control.

The case records of 25 patients who received transdermal fentanyl as a primary analgesic during routine hospice care were surveyed for pain control and rescue medication use. The majority of patients (76 percent) had cancer-related pain and were treated in hospice for an average of approximately 30 days. Most received oral medications for supplemental rescue analgesia. During the sampling periods, on average, pain intensity was reported as mild. Over the same periods, patients required a mean of 6.1 (+/- 0.7) doses of rescue medication per day, with a range of zero to 12 doses per day. Five patients required rescue dosing every two hours on some treatment days. Although adequate pain control was generally accomplished with transdermal fentanyl in the group as a whole, the frequency of rescue dosing outside of the initial titration period appears unacceptably high.

Changes in plasma nephelometry after oral fat loading in children with normal and abnormal small intestinal morphology.

A standardized oral fat load has been given to 66 children having duodenal or jejunal biopsy, and to 10 children presumed normal. The rise in plasma light scattering intensity (LSI) measured by nephelometry between the fasting and 2-hour postload level (0-2 hour) showed good correlation with the small intestinal morphology in patients suspected of having coeliac disease. In those who had had recurrent diarrhoea and gastroenteritis, the fat load test did not predict small intestinal morphology. Serial studies in 5 treated patients with malabsorption showed increase in the 0-to 2-hour LSI, with corresponding improvement of small intestinal morphology and clinical state.

Origins of anthropoid intelligence.

The development of the extrastriate visual system relative to the striate system was estimated indirectly by measuring the volumes of the lateral posteriorpulvinar complex and lateral geniculate nucleus in six varieties of mammals selected on the basis of their propinquity with Anthropoidea [oppossums, hedgehogs, rats, squirrels, tree shrews and bushbabies]. The same animals were tested on two related behavioral tasks [spatial and visual reversal learning] whose successful achievement requires a simple sort of abstraction. The results show that the ability to learn visual reversal, but not spatial reversal, corresponds closely to the relative degree of development of the extrastriate system. Since the variation in both these behavioral and morphological characteristics also parallels the phylogenetic dimension, the recency of common ancestry to anthropoids, the evolutionary origin of the anthropoid capacity for visual abstraction is suggested.

Survival of infants with unoperated myeloceles.

Of the infants with spina bifida referred to a neonatal surgical unit over three years and denied early closure of the myelocele, a significant proportion survived long enough for procedures to drain hydrocephalus to be needed. The key decision in the management of this condition is not whether myeloceles should be closed but whether hydrocephalus should be treated.

Two cases of interstitial deletion 1p.

We report two cases of interstitial deletion of the short arm of chromosome 1. The first was a 10 year old boy whose karyotype was 46,XY,del(1) (p22.1p31.2); the second was a 6 month old boy with a chromosome complement of 46,XY,del(1) (p22.3p31.3). A number of the malformations observed were common to both cases. There has been one previously reported case with the same breakpoints as our case 1 and a phenotype that was strikingly similar.

Perlman and Wiedemann-Beckwith syndromes: two distinct conditions associated with Wilms' tumour.

Though children with Perlman and Wiedemann-Beckwith syndromes have a number of features in common, the two conditions are probably separate entities. The distinction may not always be easy, however, partly because of the extreme rarity of Perlman syndrome, only nine cases of which have been reported so far. We report two siblings, initially diagnosed as having Wiedemann-Beckwith syndrome, in whom the correct diagnosis of Perlman syndrome was made only after an autopsy on the second child. By comparing and contrasting the features of Perlman and Wiedemann-Beckwith syndromes in this report we hope to make it easier to distinguish the two conditions.

Neuroanatomical basis of binaural phase-difference analysis for sound localization: a comparative study.

Four varieties of mammals whose medial superior olives range from large to none at all were tested for their ability to localize single, brief tone pips at various frequencies. Although each animal could localize high-frequency tone pips, their ability to localize middle- and low-frequency tone pips corresponded to the size of their medial superior olive (MSO). Since this latter range of frequencies is the one in which binaural phase-difference cues predominate, this anatomical-behavioral correspondence supports the idea that MSO is the chief binaural time-analyzing center for sound localization.