The maturation of the ventral root-spinal cord transitional zone. An ultrastructural study. Initially, ventral motoneurone axons in the transitional zone are closely apposed to one another. They subsequently become progressively separated by astrocyte processes which grow into the axon bundles. These processes become progressively more numerous and project into the ventral rootlet as a glial dome. This disappears with maturation, the surface of the transitional zone becoming level with that of the surrounding cord. At first, a considerable length of the axon in and deep to, the transitional zone is covered only by astrocyte processes. The sleeve of oligodendrocytic cytoplasm myelinating the axon extends distally along it towards the cord surface, thus decreasing the length of axon covered by astrocyte processes. Concurrently, the Schwann cell myelinating the most proximal peripheral internode becomes invaginated into the cord over lengths of 50 micrometer or more. Finger-like processes stem from its central end and abut on the nodal axolemma, as in peripheral nodes. However, a few astrocyte processes remain closely applied to the nodal axolemma, even at maturity. In the adult, the attachment zone consists of closely packed invaginations, each containing the central end of a Schwann cell and its myelin sheath, presenting a honeycomb appearance.


Hereditary distal myopathy with onset in early infancy. Observation of a family. The study of a family affected with hereditary distal myopathy with onset in early infancy is presented. Complete neurological examination was necessary in several members of the two last generations to discover the existence of the abnormalities of which they were unaware. The propositus was the most affected member of the family iwth distal paresis of the upper and lower extremities and selective paresis of the deltoid muscles. In addition he had kyphoscoliosis, talipes valgus and limitation of mobility of several joints. The onset of the disease was estimated as before the age of 2 when the child started walking. There was no progression of the disease. Clinical examination suggested a myopathic origin of the condition. A sural nerve biopsy was normal. Light-microscopy histochemical studies disclosed a predominance of type I fibres which were at the same time hypotrophic. Subsarcolemmal deposits of mitochondria were present although they were scanty and of normal ultrastructural appearance. In view of the morphological presentation it is postulated that this disease should be classified within the groups of myopathies accompanied by disproportion of fibres and selective atrophy of type I fibres.


Analysis of the electrical muscle activity during maximal contraction and the influence of ischaemia. (1) The mechanism underlying muscle fatigue has been studied in maintained isometric maximal contraction of the wrist flexor muscles under normal and ischaemic conditions. Automatic EMG analysis has been used to show the level of motor unit firing rates in fatiguing contractions. (2) Under non-ischaemic conditions the decay of force, turns and amplitude is about the same, whereas during ischaemia force and to a lesser extent amplitude pulses, decline steeply towards zero, while turns, representing the number of impulses, remain in the non-ischaemic range. (3) Depending on the duration of the ischaemia applied before contraction, force and amplitude are initially reduced but turns are nearly unchanged compared with the non-ischaemic values. It is suggested, that this is due to nerve blocking of high threshold motor units. (4) The results show that transmission failure at the neuromuscular junction is a minor factor in muscle fatigue and that this structure is not greatly affected by ischaemia. (5) It is believed that in the first phase of muscle fatigue the force decline is connnected with a slowing of discharge rates. This change of firing frequencies with time must be considered optimal in respect to the force produced because higher as well as lower discharge rates would reduce the force development. In the later phase it is possible that contractile element fatigue, connected with a reduction of action potential amplitudes of single muscle fibres, predominates, especially when the blood supply is obstructed.


Protein fractions of lumbar, cisternal, and ventricular cerebrospinal fluid. Separate areas of reference. Ventricular (n=27), cisternal (n=33) and lumbar (n=127) cerebrospinal fluid of "non-diseased" reference persons was investigated. The following measurements were taken: (1) Total protein, albumin, immunoglobulin A,G, M (IgA,G,M) in unconcentrated cerebrospinal fluid (CSF). (2) Protein fractions in the microzone electrophoresis of concentrated CSF. Albumin and IgG concentrations were highly correlated in all the samples, regardless of their origin. Therefore, bivariate areas of reference as well as interdependent regression coefficients were computed for the paired data. The regression lines of the 3 different areas of reference (ventricular, cisternal, lumbar) ran parallel to each other, displaced along the axis of the IgG concentration: approximately 10% of the lumbar IgG does not originate directly from serum. Although the albumin concentration increased 2.2 times, and the IgG 2.6 times, from ventricular to lumbar region, the concentration of pre-albumin decreased by a factor of 0.7. The concentration of IgA never surpassed the limits of detection set by this method (8 mg/I), in spite of its similarity to IgG regarding molecular weight and size. The observations strengthen the assumption that selective functions are present at the blood-CSF barrier. In 4 illustrative cases with a chronic inflammatory process, the discriminating power of the different reference areas was demonstrated. The findings should be evaluated in a multivariate manner, considering the location from which the sample was obtained.


Spectrophotometry of the CSF (CSF-SPE) and computer tomography (CT) in traumatic head injuries. Combined examinations with quantitative CSF spectrophotometry (CSF-SPE) and computer tomography (CT) were performed on 53 patients with traumatic head injuries. In cerebral concussion the results were mainly normal in both examinations. In cerebral contusion bleeding patterns were found by CSF-SPE in all subjects, with a special bleeding pattern (S2 pattern) occurring in 86%. CT showed findings described as typical for contusion in 8 of 14 examined patients, the remaining CT scans showing questionable or normal signs. In extra- and intracerebral haematomas, all patients had bleeding patterns on the CSF-SPE. A special bleeding component (H factor) was found in about 72%. The H component was not observed during the first 3 to 4 days after the trauma. All but one patient examined later than the 4th day had an H component with or without an S-pattern. CT demonstrated a haematoma in 14 of 18 verified haematoma patients, while 4 subjects with subdural haematoma (e.g. one third of this group) had questionable CT findings. The combined examinations with CT and CSF-SPE, being complementary to each other, are of great value in the different diagnosis of traumatic head injuries.


A genetic study of subacute and chronic spinal muscular atrophy in childhood. A nosological analysis of 124 index patients. A genetic study of the subacute spinal muscular atrophies (SMA) of late infancy and early childhood has been undertaken. All such patients with chronic disease (with ages at onset up to 14 years, and excluding SMA Type I) known to 2 large Neurological Centres were reassessed clinically and genetically. There were 124 index patients (67 females and 57 males) and 17 secondary cases, which formed two consecutive unselected series. To investigate the genetic composition of this group, 4 nosological approaches were used; cluster analysis of clinical features of the disease, Haldane's sib-sib analysis on familial cases, interpretation of frequency distribution histograms, and a segregation analysis. A single autosomal recessive gene accounts for over 90% of cases, causes a clinical syndrome which manifests its first clinical signs before 5 years of age and in almost all cases before two years of age, but which is compatible with life into the third decade. Moderate intrafamilial discordance for some clinical features may be observed, but no genetic heterogeneity within this group was demonstrated. A small group of cases is caused by (a) new dominant mutation(s), or (b) is composed of phenocopies, or both. This relatively uncommon form may comprise the majority of late-presenting cases, and may account for all cases which manifest the first signs after 5 years of age. The spectrum of age-at-onset of this group cannot be determined at present, but the disease may be manifest before the age of two years; it is clinically indistinguishable from SMA caused by an autosomal recessive gene. The literature has been reviewed in the light of these findings. Empirical risks for use in genetic counselling are presented.


Essential fatty acid deficiency and CNS myelin. Biochemical and morphological observations. Essential fatty acid (EFA) deficiency was induced by feeding pregnant rats a fat-free diet 10--12 days after impregnation and maintaining the offspring on this diet until 120 days of age. EFA-deficiency rats demonstrated marked alterations in the fatty acid composition of ethanolamine phosphoglycerides (EPG's) from myelin subfractions. A decrease in the fatty acids of the linoleic (n-6) and linolenic (n-3) families was accompanied by an increase in the non-essential fatty acids of the oleic (n-9) family. These alterations decreased the unsaturation index of heavy myelin by 23% and that of light myelin by 10%. The EPG fatty acid composition of heavy myelin from control animals contained a higher percentage of polyunsaturated fatty acids than the light myelin which contained more monounsaturated fatty acids. These differences may be a reflection of distinct anatomical locations or functional properties of the subfractions. The differences between light and heavy myelin EPG fatty acids were not maintained during EFA deficiency. Morphologically, 1 mum thick sections revealed vacuoles within the optic nerve of EFA-deficient rats. Ultrastructurally these vacuoles were identified as fibers undergoing Wallerian degeneration and fibers demonstrating intramyelinic splitting. No qualitative changes were found in oligodendrocytes, astrocytes or vascular elements within EFA-deficient optic nerve. EFA deficiency did not alter the diameter of fibers within the optic nerve. These results show that although there is no apparent decrease in the degree of myelination within the optic nerve, morphological changes do occur in fibers of EFA-deficient optic nerve concomitantly with alterations in the EPG fatty acids of myelin subfractions.


3,3'-Iminodipropionitrile induced centrifugal segmental demyelination and onion bulb formation. Centrifugal segmental demyelination extended from the proximal to the distal portion, and onion bulb formation in the extraspinal ventral root occurred following the axonal lesion of the intraspinal ventral root induced by 3,3'-iminodipropionitrile. These results suggest that axonal factors may be responsible to segmental demyelination and onion bulb formation.


Increased endocytosis with lysosomal activation in skeletal muscle of dystrophic mouse. Endocytosis in dystrophic muscles was studied by a combination of biochemical, radiochemical, and light and electron microscopic techniques. It was observed that the uptake of horseradish peroxidase (HRP) and 3H-Inulin in vitro was increased in leg skeletal muscles from dystrophic mice compared with littermate controls. Endocytosis of HRP in vivo was also increased in dystrophic muscles. When HRP was administered intravenously, light microscopic examination of the muscles showed that the macromolecular tracer was present not only in the extracellular space but also as intracellular deposits in several dystropic muscle fibers. Ultrastructural examination of these fibers showed HRP to be present in membrane limited bodies of variable size, some of which likely represented secondary lysosomes, located preferentially close to the A-I junction. HRP was also found inside vacuoles which were sometimes in close vicinity to autophagic vacuoles. Primary uptake vesicles containing HRP appeared to originate from the sarcolemma and the transverse tubules. Biochemical determination of lysosomal enzyme activities revealed elevated levels of both cathepsin D and N-acetylglucosaminidase in dystrophic muscles as compared with controls. The results suggest an increased endocytic activity in dystrophic muscles with distribution of exogenous marcromolecular tracers into endocytic vesicles and lysosomal structures. The hypothesis is put forward that endocytic activity constitutes an important mechanism of lysosomal activation in dystrophic muscles.


Postnatal development of visually evoked activity within motor cortex of cat. 1. The development of visually evoked activity within motor cortex was studied in chloralose-anesthetized kittens of 3, 4, and 5 mo of age and adult cats. 2. The slow-wave response from motor cortex of the adult cat is a triphasic negative-positive-negative wave. In 3-mo-old kittens the response is only a long-duration negative wave, while at 4 mo the positive and late negative waves emerge, and at 5 mo of age the adult form of the response is present. 3. Single neurons in the adult respond to the light during the positive component of the slow-wave response. When only the negative wave is present in kittens of 3 and 4 mo of age, neurons do not respond to the photic stimulus. At 5 mo of age the correlation between unit activity and the positive component of the response is identical to the adult. 4. The laminar analysis of the positive component of the response suggests that it originates relatively superficially in cortex and migrates down toward the deeper layers. Its correlation with unit activity indicates that the positive component represents excitatory postsynaptic potentials. 5. These results are consistent with an excitatory drive on neurons within motor cortex undergoing development change until the 5th mo of life.


Early edematous lesion of pyrithiamine induced acute thiamine deficient encephalopathy in the mouse. Pyrithiamine induced acute thiamine deficient encephalopathy in the mouse is one of the possible animal models of human Wernicke-Korsakoff syndrome. In this experiment, the adult male Swiss Mice, treated with a daily subcutaneous injection of pyrithiamine in conjunction with a thiamine deficient diet, abruptly developed unique encephalopathic signs on day 10. In the animals sacrificed immediately after the onset of the disease, the gross examination of the brains revealed a small number of minute hemorrhagic lesions in the thalamus, mammilary bodies and pontine tegmentum, including the medial and lateral vestibular nuclei. When spared the hemorrhage, these regions appear intact grossly and in paraffin sections, but were found to be significantly altered in Epon sections. In semithin Epon sections of the pontine tegmentum, there was edematous swelling of all the astrocytes and oligodendrocytes and occasional myelin sheaths. By electron microscopy, the edema of astrocytes involved both nucleus and cytoplasm extensively. The oligodendroglial edema was severe in the peripheral cytoplasm, particularly in the inner loops of the myelin sheaths and only moderately in the nuclei, perinuclear cytoplasm and outer loops. Disintegration of the myelin lamellae occurred when edema of the inner loops had advanced. The axis cylinders surrounded by the edematous loops were essentially intact. In contrast to such glial cell damage, the nerve cells and blood vessels were not altered. These findings suggest that (1) astroglia and oligodendroglia are the cells most sensitive to thiamine deficiency and (2) the resultant glial cell injury is the initial change of thiamine deficient encephalopathy in man and in experimental animals.


Calcium and potassium changes in extracellular microenvironment of cat cerebellar cortex. 1. Local stimulus-evoked changes in concentration of extracellular calcium ions, [Ca2+]0, and potassium ions, [K+[0, were measured in the cerebellar cortex of the cat using paired ion-selected micropipettes. 2. Repetitive stimulation of 30 s duration decreased [Ca2+]0 from a base line of 1.2 mM to as low as 0.8 mM and increased [K+]0 from 3 mM to as much as 8 mM. The magnitude of the changes was directly related to stimulus frequency. Laminar analysis showed that the greatest ion changes occurred at the level of maximum parallel fiber-Purkinje cell dendrite stimulation, but that the [Ca2+]0 changes were more localized than the [K+]0 changes. 3. Combining real-time current-source density measurement with [K+]0 determination and local manganese application, showed that the Mn blocked parallel fiber-Purkinje cell synaptic transmission, but that much of the [K+]0 changes persisted. Thus, a large part of the [K+]0 flux most probably originated in the parallel fibers. In contrast, [Ca2+]0 changes were abolished by the Mn, indicating that the decrease in this ion was probably associated with synaptic transmission or dendritic events. 4. In a few cases, spreading depression occurred in the cat cerebellar cortex. This could be accompanied by decreases in [Ca2+]0 to as low as 0.12 mM and increases in [K+]0 in excess of 48 mM. 5. These results show that significant changes in [Ca2+]0 and [K+]0 occur during cerebellar stimulation and indicate possible origins of the ion fluxes in terms of neuronal elements. This work also shows that the cerebellar cortex of the cat can support spreading depression. The present results, together with those of earlier studies on [Ca2+]0 and [K+]0 changes in the presence of aminopyridine in the cat cerebellum, suggest that synaptic or dendritic electroresponsive properties may play a role in the observed [Ca2+]0 and [K+]0 changes.


Generation of scratching. I. Activity of spinal interneurons during scratching. 1. In decerebrate, curarized cats, stimulation of the cervical spinal cord evoked fictitious scratching (9), i.e., periodical activity of the hindlimb motoneurons with a discharge pattern typical of actual scratching (cycle duration about 250 ms, flexor phase about 200 ms, extensor phase about 50 ms). During fictitious scratching, extra-cellular records were obtained from 182 spinal neurons located in different regions of the gray matter cross section (except for the motor nuclei), from segments L4 and L5. 2. The firing rate of 73% of neurons was rhythmically modulated in relation with the scratch cycle. Most of the modulated neurons fired in bursts and were silent between bursts. They were located mainly in Rexed's (22) layer VII. 3. Burst onsets ("switchings on" of the neurons) were distributed rather evenly throughout the scratch cycle except for a small maximum at the very beginning of the cycle (the cycle was assumed to start with the termination of the extensor phase). Burst terminations ("switchings off") in the overwhelming majority of the neurons were distributed over the last-third part of the cycle. As a result, those neurons which began to fire earlier in the cycle usually had longer bursts, compared to the neurons which began to fire later. Besides, since there were very few switchings off in the first half of the cycle, the number of simultaneously active neurons increased during the first half of the cycle, reached the maximum somewhat later than the middle of the cycle, and considerably decreased by the end of the cycle. 4. With more intensive scratching, the firing rate in the bursts considerably increased in all neurons tested, while the duration of the scratch cycle changed only slightly. 5. A correlation between the burst position in the cycle and the behavior during the latent period of scratching (when stimulation of the cervical spinal cord had already been started but rhythmical oscillations had not yet appeared) was found in many neurons. Most of the neurons which began to fire at the beginning of the scratch cycle and had long bursts were tonically activated during the latent period. On the contrary, most of the neurons which fired in short bursts at the end of the cycle were either inhibited or not affected during this period. 6. A correlation betwen the burst position in the cycle and the frequency pattern was found in many neurons. In most of the neurons which began to fire in the first half of the cycle (except for the very beginning), the discharge rate increased in the course of the burst. In the remaining neurons, the discharge rate changed only slightly during the burst. 7. Hypotheses concerning organization of the spinal mechanism of scratching are discussed.


Effect of lead on the developing peripheral nervous system. The effect of lead on the developing nervous system was studied in the Long-Evans rat. Pups were intoxicated with lead from day 2 through the 20th day of life with a dosage of 1 gm Pb/kg body weight. Doses were administered via gastric gavage on the second and third days of life, and bidaily thereafter. Lead-treated and age-matched controls were then studied at selected intervals up to and including 20 days of age. Central and peripheral nervous systems were examined by light and electron microscopy. Morphometric analysis focused on defined segments of proximal and distal sciatic nerves and the 6th dorsal and ventral lumbar roots. For teased fiber studies, a segment of the contralateral proximal sciatic nerve was used. The investigation revealed that during the period studied, the myelin formed is stable. Multiple lead effects, however, were found: the Schwann cell is initially swollen but this effect gradually wanes during the 20 day period; myelin compaction is initially delayed, particularly in the ventral roots; axonal segregation proceeds, but appears to be accelerated in the ventral roots of the lead-treated pups where the larger bundles of naked axons disappear by five days of life. All of the changes noted, except axonal segregation, are reversed in the face of continued lead intoxication. While the hallmarks of "classical" lead neuropathy--segmental demyelination and the selective involvement of large fibers were not observed--the sensitivity of the somatic efferent fibers to lead was apparent in the accentuation of the lead effects in the ventral roots.


Generation of scratching. II. Nonregular regimes of generation. 1. The activity of muscle nerves and that of spinal interneurons from the L4 and L5 segments was recorded during fictitious scratching (5), which was evoked in decerebrate curarized cats by stimulation of the cervical spinal cord. In some experiments, rhythmical generation was disturbed by stimulation of the fifth lumbar dorsal root (DL5). 2. Excluding the very beginning of scratching, rhythmical generation was usually rather regular: fluctuations of the cycle duration were less than +/-5%. But changes in the stimulation strength, in the stimulating electrode position, and in the hindlimb position led to changes of the generation regime. In different regimes, the mean value of the cycle duration could differ by 20-30%. No correlation was found between mean durations of flexor and extensor phases for different regimes. 3. Rhythmical generation was possible only if the hindlimb was put to "scratch posture," i.e., deflected forward. Generation immediately stopped when the limb was deflected backward, and immediately started when it was returned to scratch posture. 4. In some experiments, stimulation of the cervical spinal cord first resulted in generation of slow oscillations with the temporal pattern typical of stepping (cycle duration about 500 ms, flexor and extensor phases being almost equal to each other). Then, during 5-20 cycles, gradual transition to a normal scratch cycle (about 250 ms) occurred mainly due to considerable shortening (5-10 times) of the extensor phase. In some experiments, considerable spontaneous variations of the flexor phase were observed, while the extensor phase was constant. 5. A single stimulus applied to DL5 considerably affected the cycle duration. Repetitive DL5 stimulation,with a rhythm close to that of scratching, resulted in synchronization of the spinal generator by the stimuli. 6. Spinal interneurons recorded during transition from slow oscillations to a normal scratch cycle only slightly changed phases of their activity in relation to the activity of motoneurons. 7. A hypothesis is advanced that generation of different kinds of limb movements is produced by one and the same central spinal mechanism which can operate in different regimes. The role of sensory input for operation of this mechanism is discussed.


External nucleus of inferior colliculus: auditory and spinal somatosensory afferents and their interactions. 1. The discharges of 129 units were studied in the external nucleus of the inferior colliculus of 11 anesthetised and paralyzed cats. This region is known to receive fibers from auditory nuclei and the dorsal column nuclei. 2. Stimuli used were pure tone bursts, monaural or binaural, tactile stimulation of the body surface, and electrical stimulation of the dorsal columns (DC) at a low cervical level and of the contralateral and ipsilateral tibial nerves. 3. Forty-six percent of units were only influenced by one type of stimulation (26% auditory, 20% DC). Of the remaining bimodally influenced units, the majority was excited by pure tone stimuli and inhibited by DC stimulation. 4. A small proportion of the total population (18%) was excited by both DC and auditory input, and units sensitive to both tones and tactile stimulation of the skin were rare (4%). 5. Auditory tuning curves were generally very broad compared with those of units in the central nucleus of the inferior colliculus. Similarly, somatic receptive fields were large and usually extended over a whole limb. 6. The majority of tone-responsive units were influenced binaurally (70%); most somatic receptive fields were located on the contralateral fore- or hindlimb (16/18). 7. The results indicate that both auditory and somatosensory information is contained in the discharges of units in the external nucleus of the inferior colliculus. 8. Speculations are made about the role of this nucleus in descending auditory input to the spinal cord and in the comparison of auditory and cutaneous information during sound-evoked coordinated body movements.


Eye alignment in kittens.

Eye alignment in kittens. 1. The alignment of the pupillary axes and of the visual axes has been measured in 23 normally reared cats ranging in age from 14 days to adulthood. 2. In agreement with a previous report, we find that pupillary divergence, as measured from photographs, tends to decrease during the first 2 mo of life. 3. The angle between the visual axes of cats of various ages was determined during paralysis by plotting the receptive fields of neurons in cortical area 17, and extrapolation to the angle of alignment of the freely moving animal was accomplished by comparing pupillary photographs taken before and after immobilization. Results obtained by this method reveal that in cats of all ages the visual axes are convergent, and that the average angle of convergence is approximately the same at all ages. 4. We conclude that young kittens may be capable of coordinated binocular vision. Further study will be required to determine whether animals as young as 2 wk are able to align their eyes accurately so as to bring the two retinal images of object space into register. 5. Pupillary divergence decreases during development as a result of changes in the geometry of the eye characterized by a reduction of the angle between the pupillary axis and the visual axis in each eye. This angle changes from around 25 degrees at 14 days to around 16 degrees in adulthood. 6. The role of visual experience in the maintenance of normal eye alignment was investigated by rearing five cats in darkness until the age of 4-7 mo. In three animals, visual axis alignment was within the normal range. The two remaining cats were slightly exotropic. 7. A change occurs during development in the apparent cyclotorsional alignment of the eyes, as determined by measuring the intorsional angle formed by the two slit pupils. This angle increases during the 1st and 2nd mo, assuming a mean value of 14 degrees. In dark-reared cats the increase continues through the 3rd mo, culminating in an abnormally large angle of pupillary intorsion (mean of 24 degrees). The possibility that these changes reflect true shifts in cyclotorsional alignment of the eyes is discussed.


Space and frequency are represented separately in auditory midbrain of the owl. 1. The influence of sound location and sound frequency on the responses of single units in the midbrain auditory area (MLD) of the owl (Tyto alba) were studied using a movable sound source under free-field conditions. With this technique, two functionally distinct regions in MLD have been identified: a tonotopic region and a space-mapped region. 2. MLD units were classified according to their receptive-field properties: 1) limited-field units responded only to sound from a small, discrete area of space; 2) complex-field units exhibited two to four different excitatory areas separated by areas of reduced response or inhibition: 3) space-preferring units responded best to a certain area of space, but their fields expanded considerably with increasing sound intensities; 4) Space-independent units responded similarly to a sound stimulus regardless of its location in space. 3. Limited-field units were located exclusively along the lateral and anterior borders of MLD. These units were tuned to sound frequencies at the high end of the owl's audible range (5-8.7 kHz). They usually responded only at the onset of a tonal stimulus; but most importantly, the units were systematically arranged in this region according to the azimuths and elevations of their receptive fields, thus creating a physiological map of auditory space. Because of this latter, dominant aspect of its functional organization, this region is named the space-mapped region of MLD. 4. The receptive fields of units in the larger, medial portion of MLD were of the space-independent, space-preferring, or complex-field types. These units tended to respond in a sustained fashion to tone and noise bursts, and these units were arranged in a strict frequency-dependent order. Based on this last property, this region is named the tonotopic region of MLD. 5. Because of the salient differences in the response properties of their constituent units, it is argued that the space-mapped region and the tonotopic region are involved in different aspects of sound analysis.


Specificity of afferent and efferent regeneration in the cockroach: establishment of a reflex pathway between contralaterally homologous target cells. 1. In 132 cockroaches the main leg nerve on one side (right), of the metathoracic segment was crossed to the opposite (left) side and allowed to regenerate. In 3-8 wk, 59% of the animals displayed reflex activity in the left leg (behaviorally demonstrated by leg withdrawal following tarsal stimulation). 2. EMGs from the femoral extensor revealed potentials characteristic of normal activity in the extensor, which is innervated by an identified motor neuron, Ds. 3. Intracellular recordings from processes within the right hemiganglion of the metathoracic ganglion (CNS) demonstrated 1:1 activity between a unit in the CNS recording and the EMG of the left extensor. Subsequent intracellular staining revealed that the unit was on the right side of the CNS and was identified as motor neuron Ds by the location of its soma and dendrites. This finding indicated that specific, contralateral, efferent reinnervation occurs in the cockroach. 4. In normal cockroaches a monosynaptic reflex exists between hair plate afferents and Ds. A temporal analysis (stimulus-interval histogram) indicated that the reflex is also established in the crossed-regenerated animals. These data suggested that specific contralateral afferent reinnervation also occurs in the cockroach and that the monosynaptic nature of the normal reflex was reestablished. 5. Therefore, cell-to-cell specificity in neuron-to-neuron or neuron-to-muscle interactions not only occurs in normally developing or regenerating animals but also occurs between contralaterally homologous target cells, given the proper experimental conditions. It is also suggested that this experimental procedure of redesigning pathways may be a useful tool for further studies of behavior.


Physiological consequences for the cat's visual cortex of effectively restricting early visual experience with oriented contours. 1. The early visual experience of nine cats was restricted to viewing horizontal or vertical lines inside opaque goggles. 2. When the kittens were 3-4 mo old, extracellular recordings were made in the primary visual cortex. To obtain a representative sample of cortical cells, units were studied at regularly spaced intervals along the course of electrode penetrations traveling oblique to the cortical surface. An automated assessment of preferred orientation using a computer-driven optical display was employed, and during the recording session the experimenters did not know which orientation(s) each animal had viewed in early life. 3. In the cats that viewed horizontal lines with one eye and vertical lines with the other during rearing, two major findings of previous workers (14) were confirmed. First, a majority of units were not selective for orientation. Second, units with preferred orientations near vertical tended to be activated exclusively by the eye that had viewed vertical, and likewise for horizontal. 4. In cats that viewed lines of the same orientation with both eyes during rearing, a substantially smaller proportion of units were selective for orientation; the preferred orientations of these units also tended to match the orientation to which the cats had been exposed. 5. Portions of some electrode penetrations showed an orderly arrangement of cells according to preferred orientation similar to that seen in normal cats, but with regions over which only nonselective cells were found. Many penetrations appeared less orderly. 6. The results are consistent with a role for early visual experience in maintaining the responsiveness and innate selectivity of cortical neurons, although they cannot entirely rule out the possibility that experience may alter or determine the preferred orientation of some cells.


Receptive-field properties of neurons in different laminae of visual cortex of the cat. 1. Receptive-field properties of neurons in the different layers of the visual cortex of normal adult cats were analyzed quantitatively. Neurons were classified into one of two groups: 1) S-cells, which have discrete on- and/or off-regions in their receptive fields and possess inhibitory side bands; 2) C-cells, which do not have discrete on- and off-regions in their receptive fields but display an on-off response to flashing stimuli. Neurons of this type rarely display side-band inhibition. 2. As a group, S-cells display lower relative degrees of binocularity and are more selective for stimulus orientation than C-cells. In addition, within a given lamina the S-cells have smaller receptive fields, lower cutoff velocities, lower peak responses to visual stimulation, and lower spontaneous activity than do the C-cells. 3. S-cells in all layers of the cortex display similar orientation sensitivities, mean spontaneous discharge rates, peak response to visual stimulation, and degrees of binocularity. 4. Many of the receptive-field properties of cortical cells vary with laminar location. Receptive-field sizes and cutoff velocities of S-cells and of C-cells are greater in layers V and VI than in layers II-IV. For S-cells, preferred velocities are also greater in layers V and VI than in layers II-IV. Furthermore, C-cells in layers V and VI display high mean spontaneous discharge rates, weak orientation preferences, high relative degrees of binocularity, and higher peak responses to visual stimulation when compared to C-cells in layers II and III. 5. The receptive-field properties of cells in layers V-VI of the striate cortex suggest that most neurons that have their somata in these laminae receive afferents from LGNd Y-cells. Hence, our results suggest that afferents from LGNd Y-cells may play a major part in the cortical control of subcortical visual functions.


Effect of auditory cortex ablation on localization and discrimination of brief sounds. 1. Dogs with bilateral auditory cortex lesions were tested on their ability to localize and discriminate brief sounds. In each test the animals were required to approach one of two goal boxes in order to indicate their response. 2. The results showed: a) that the operated animals could not solve the localization tasks when the goal boxes were located more than 125 cm away, but could solve the task if the goal boxes were located closer to the animal; b) that the operated animals could successfully discriminate brief bursts of click trains (i.e., 100/s versus 10/s, 0.3 s duration) even when required to indicate their discrimination by moving to goal boxes located 250 cm away, in spite of the fact that they could not successfully localize these sounds under similar conditions; c) that the operated animals tracked the source of a continuous sound instead of localizing it in a normal manner. 3. It appears that the deficit in sound localization resulting from cortical ablation is not due to any impairment in auditory attention or memory. Furthermore, the deficit cannot be ascribed to an inability to make a spatial response to an auditory cue. Instead, the deficit may be the result of a disconnection of the sound-localization mechanism from the motor mechanism necessary for some, though not all, behavioral responses.


Neural correlates of auditory fatigue: frequency-dependent changes in activity of single cochlear nerve fibers. 1. These experiments were designed to test whether intense pure tones produced greater depression of cochlear nerve fibers tuned to the exposure frequency or of those tuned to frequencies above the exposure frequency. Spike discharges of single fibers were studied in anesthetized cats before, during, and after exposures lasting 1 min. Exposure frequency was varied relative to each fiber's characteristic frequency (CF), and was either at the CF or 1/2 octave above (+1/2 oct) or 1/2 octave below (-1/2 oct) the CF. Exposure levels were 85 or 90 dB SPL. Effects of the various exposures on driven discharge rates were evaluated using standard test stimuli at each fiber's CF. In addition, nonevoked discharges were measured during the brief quiet intervals between test stimuli ("interstimulus activity") as well as during extended quiet periods ("resting activity"). Major results were as follows: 2. All the exposures resulted in depression of the driven discharge rates; however, these effects were strongly dependent on the exposure frequency. The depression was greatest and endured the longest following -1/2 oct exposures at 90 dB. The CF exposures at 85 and 90 dB were much less depressant, as were exposures at -1/2 oct at 85 dB; these three exposures resulted in very similar recovery functions. The +1/2 oct exposures produced little or no depression, whether at 85 or 90 dB. 3. Interstimulus activity was depressed immediately following all exposures, but recovered to normal quickly than did driven discharge rates. Following exposures at -1/2 oct at 90 dB, recovery was non-monotonic in that an extended period of supernormality preceded the return to normal rates. During this period of elevated activity, the interstimulus activity approached but never exceeded the resting rate of the same fiber. 4. Resting activity recovered even more rapidly than interstimulus activity, being completely normal by 1 min following all exposures. 5. These results constitute the first demonstration that the CF is not necessarily the most depressant exposure frequency for a given cochlear nerve fiber. Further, the results imply that the half-octave (or greater) shifts of the point of maximum hearing loss, so characteristic of auditory fatigue, may be accounted for by frequency-dependent alterations in the responsiveness of cochlear nerve fibers.


Head injury and coagulation disorders.

Head injury and coagulation disorders. Coagulation studies (plasma fibrinogen, ethanol gelation test, and fibrin/fibrinogen degradation product concentration) were done in 150 patients who were admitted after blunt head injury. Results were abnormal in 60 patients and were found to be correlated with the level of consciousness and with the presence of neurological signs. Many of these patients had fractures, but findings in a control group of 26 patients with major fractures without head injury indicate that fractures were not of paramount importance in causing clotting changes. Conclusive evidence of disseminated intravascular coagulation was found in 12 patients. Cases with a fatal clinical course were mostly associated with very high fibrin/fibrinogen degradation product concentrations. Some case histories are reported, confirming the hypothesized correlation between coagulation results and brain tissue destruction rather than brain compression. It was concluded that some degree of disseminated intravascular coagulation in patients with blunt head injury occurs more often than expected and that coagulation studies might have both diagnostic and prognostic value.


Reproducibility of regional cerebral blood flow measurements in acute severe head injury. In order to evaluate the reproducibility of regional cerebral blood flow (rCBF) measurements in pathological brain tissue, serial measurements were carried out in 13 determinations performed in patients who were comatose after severe head injuries within the first 2 weeks after the head trauma. The xenon-133 intra-arterial method was used for the flow measurements, and the flow was studied separately in 16 areas of the brain, producing 197 regional double determinations. The patients were maintained in a steady state during and between the measurements, and only differences of less than 2 mm Hg in the arterial CO2 pressure and less than 5 mm Hg in the perfusion pressure were tolerated. The reproducibility was found to be reasonably good as regards initial slope-flow indices and height/area flow indices and height/area flow values, whereas that of the compartmentally calculated flow parameters was poorer. On dividing the series into severely and moderately pathological areas, it could be shown that the reproducibility of the flor values in the moderately pathological brain areas was acceptable and similar to the results reported by others, whereas the reproducibility in the most severely pathological areas of the brain was rather poor, as regards the flow in the fast compartments. The correlation between the various flow parameters was found to be fairly good.


Deep vein thrombosis and low-dose heparin prophylaxis in neurosurgical patients. By the use of 125I-labeled fibrinogen test, the incidence of postoperative deep vein thrombosis (DVT) and the effectiveness of prophylactic low-dose heparin treatment were investigated in 110 patients who underwent elective neurosurgical procedures. Fifty patients were appointed randomly to a control group and 50 to a heparin group (10 patients were excluded since they had DVT before surgery). The incidence of DVT was reduced from 34% in the control group to 6% in the heparin group (p less than 0.005). No statistically significant differences were observed in transfusion requirements, postoperative hemoglobin concentration, and the occurrence of postoperative hematomas between the two groups. Positive correlation was observed between DVT and motor deficit (p less than 0.05). Preoperative assessment of patients' sensitivity to the standard 5000-unit dose of heparin was performed in all treated patients and is thought an important factor in improving the safety of heparin prophylaxis.


Cervical myeloradiculopathy caused by arthrotic hypertrophy of the posterior facets and laminae. Five patients with typical cervical myeloradiculopathy caused by focal cervical spinal stenosis are presented. Dorsal intrusions into the spinal canal by hypertrophied apophyseal joints and thickened laminae resulted in cord and nerve root compression. Minor spondylotic changes were present in the floor of the spinal canal. Laminar decompression with formainotomy and facetectomy relieved the patients of their symptoms. An anterior approach should not be considered in the management of this disorder. Our findings of severe apophyseal arthrosis with lesser degrees of associated spondylosis are similar to those described in anatomical studies by other authors. While uncommon, myelopathy caused by dorsal compression of the spinal cord and nerve roots deserves specific mention so that therapy can be directed to the proper quadrants of the spinal canal wherein the significant pathology is located.


Management of recurrent CSF rhinorrhea of the middle and posterior fossa. The authors review 39 patients with cerebrospinal fluid (CSF) leaks originating from the middle or posterior fossa. They evaluate the usefulness of preoperative investigative procedures, including cisternal radionuclide scanning and the deliberate increase of intracranial pressure. The results in this series emphasize the important role that abnormal CSF dynamics play in the recurrence of problematic cases of rhinorrhea or otorrhea. The following guidelines are recommended by the authors on the basis of their recent experience: 1) if hydrocephalus is present, if the cisternogram is abnormal, or if the CSF leak is intermittent and slight, the initial treatment should be insertion of a lumboperitoneal shunt; 2) if the leak is localized in the sellar or parasellar area, a transsphenoidal approach to obliterate the leak is advised; 3) if the CSF leak originates through a dural opening into the middle ear, an intracranial repair is indicated.


Computerized tomography in hydatid cyst of the brain. From among 1500 patients who underwent computerized tomography (CT) during an 18-month period, five cases of hydatid disease of the brain were diagnosed. The preoperative diagnosis is of paramount importance as the cyst has to be removed unruptured. The CT features of this condition are practically pathognomonic. The authors discuss the CT findings in these cases and differential diagnosis with other cystic lesions of the brain. The help that this safe and sure method of investigation gives to attain preoperative diagnosis is emphasized.


South American blastomycosis presenting as a posterior fossa tumor. Case report. An unusual case of infection of the central nervous system by Paracoccidioides braziliensis, presenting as posterior fossa tumor, is discussed and the pertinent literature reviewed.


Paracoccidioidomycosis of the skull. Case report. A case of paracoccidioidomycosis of the skull is presented. No evidence of a previous lung, mucous membrane, or nervous system infection was found. Radiological and surgical findings suggested osteomyelitis. The authors stress the importance of including paracoccidioidomycosis in the differential diagnosis of osteolytic skull lesions in countries where this fungus is endemic.


Recurrence of medulloblastoma after homogeneous field radiotherapy. Report of three cases. Three cases are reported of posterior fossa medulloblastoma in children. In each case metastatic spread occurred despite homogeneous field radiotherapy to the whole neuraxis; the secondary tumor was located in the subfrontal region. In the two cases in which operative removal of the metastasis was carried out, the tumor was found to be extracerebral and was attached to the dura in the region of the cribiform plate. The "face-down" position of patients during operations on the posterior fossa makes this area the most dependent part and therefore the most likely recipient of tumor cells shed at operation. This area has not previously been included in the field of maximum dosage for radiotherapy, but as a result of these findings a modification in technique of radiotherapy has been suggested.


Congenital lumbar ridge causing spinal claudication in adolescents. Report of two cases. Two adolescent boys had classic histories and findings of spinal claudication. Their plain x-ray films were read as normal and myelograms demonstrated a ventral defect at L4-5. Surgical exploration revealed ventral bony ridges in both cases. Laminectomy initially provided substantial relief, but spinal fusion was necessary for complete abolition of symptoms.


Development of cerebellar malignant astrocytoma at site of a medulloblastoma treated 11 years earlier. Case report. A child treated for a desmoplastic medulloblastoma of the left cerebellar hemisphere at the age of 10 months developed a malignant astrocytoma in the same site 11 years later. Theories of origin of the second tumor, particularly in relation to concepts of the genesis of medulloblastoma in general, are discussed.


Basilar-middle meningeal arterial anastomosis. Case report. A rare case of basilar-middle meningeal arterial anastomosis is reported. Pertinent literature is reviewed and an embryological explanation of this anastomosis is discussed.


Lipoma of the quadrigeminal plate causing progressive obstructive hydrocephalus. Case report. A patient with congenital hydrocephalus and poor vision since early childhood, but with normal motor and intellectual development, suffered progressive mental deterioration during the last decade of life. At necropsy he was found to have severe hydrocephalus secondary to a lipoma of the midbrain tectum obstructing the aqueduct of Sylvius. In addition, the septum pellucidum was absent, the corpus callosum was thinned, and the anterior visual system was atrophic. The case emphasizes the importance of full neuroradiological investigation of congenital hydrocephalus. The possible association of intracranial lipoma with septo-optic dysplasia is discussed.


Infratentorial neuroepithelial cyst (colloid cyst). Case report. An asymptomatic neuroepithelial cyst (colloid cyst) located in the leptomeninges between the inferior colliculus and the paravermal region of the superior cerebellum was an incidental postmortem finding. The cyst was lined by ciliated pseudostratified columnar epithelium of the respiratory tract type as lell as cuboidal epithelium of the ependymal type. Its developmental relationship to previously described colloid and paraphyseal cysts in the third ventricle is discussed.


Intracranial solitary chondroma. Case report. A case of massive solitary intracranial chondroma involving the base of the skull in a 15-month-old baby boy was successfully treated by total excision. The diagnosis was greatly simplified by the us of computerized tomography, which materially helped in planning the surgical approach.


Eosinophilic granuloma of the base of the skull. Case report. The authors present an unusual case of eosinophilic granuloma arising in the region of the foramen rotundum.


Gallium-67 scintigraphy in untreated and treated non-hodgkin lymphomas. One hundred and seventy-four gallium scans of patients with biopsy-proved non-Hodgkin lymphoma were reviewed. When the lymphomas were subdivided into histologic groups, there was a significant difference in detection rates, with 62% of the histiocytic lymphomas being identified, while only 39% of the poorly differentiated lymphocytic lymphomas were detected. There was a high detection rate for lesions in the mediastinum and in extranodal locations. When analyzed with regard to therapy, the detection rate was higher in all histologic subgroups after therapy than before.


Ejection fraction by count rate from gated images. Left-ventricular (LV) ejection fraction (EF) was determined from ECG-gated images of the cardiac blood pool, by computing the relative change in net LV counts occurring in these images during systole. EFs obtained with this method gave satisfactory interobserver agreement in 20 studies reviewed by three independent observers (average r = 0.95) and also compared favorably with EFs obtained by contrast ventriculography in 39 patients (r = 0.92). The technique appears suitable for use in the evaluation of systolic function in patients with heart disease.


Femoral head activity in Perthes' disease: clinical evaluation of a quantitative technique for estimating tracer uptake. A method for quantifying the uptake of Tc-99m-labeled phosphate complexes in the femoral head has been clinically evaluated, being used specifically for studying the uptake of these bone-seeking agents in Perthes' disease. The analysis depends on the selection, by computer program, of a reliable reference area in the femoral shaft, which is then compared with the mean uptake from each femoral head. The femoral-head activity is then represented as an uptake ratio. These ratios, together with a fixed contour representing the uptake in the femoral-head regions, provide more clinical information than the radiograph or scintiphoto, particularly in the early stages of unilateral or bilateral femoral-head disease and during followup. No correlation has been found between these ratios and qualitative techniques for assessing Perthes' disease by radiograph. From the quantitative data so far obtained it is clear that osteotomy reduces the vascularity of the femoral head, and in certain cases this reduction persists for some years. Tc-99m-labeled diphosphonate compounds were used in more recent studies, and a significant increase in sensitivity was obtained, compared with earlier polyphosphate data.


Comparison of In-111-labeled platelets and iodinated fibrinogen for the detection of deep vein thrombosis. Indium-111-labeled platelets and I-125 fibrinogen were administered to dogs with experimentally induced deep-vein thrombosis. The thrombus uptake of both labeled compounds was studied as a function of thrombus age. In thrombi less than 24 hr old, thrombus-to-blood ratios for In-111 platelets were about twice as great as those obtained for I-125 fibrinogen. Excellent scintiphotos were obtained with In-111 platelets. In thrombi older than 24 hr, uptake of both agents was low, but good images were still obtained with In-111 platelets. The images in this case are not of thrombi, but rather of damaged vessel wall. Indium-111-labeled platelets are superior to iodinated fibrinogen for imaging fresh thrombi, but offer no advantage for thrombi over 24 hr old.


Preparation of iodine-125-labeled insulin for radioimmunoassay: comparison of lactoperoxidase and chloramine-T iodination. The enzymatic radioiodination of porcine insulin by a system consisting of lactoperoxidase, hydrogen peroxide, and Na125I was compared with a modified chloramine-T technique. Satisfactory specific activity of the labeled hormone was obtained with the enzymatic iodination, with much greater immunoreactivity and stability than after chloramine-T, besides being quite suitable for the measurement of low plasma insulin levels. There was a positive and highly significant correlation between the insulin concentrations measured with the two tracers, with the regression line defined by the equation: y (chloramine-T) = 8.34 + 0.99 x (lactoperoxidase).


Accidental ingestion of Tc-99m in breast milk by a 10-week-old child. Ten weeks after the birth of her first child by Caesarian section, a 27-year-old woman was admitted for evaluation of a possible central nervous system lesion. Four hours after i.v. administration of 15 mCi of Tc-99m for a brain scan, the patient breast-fed her infant; then became concerned about the possibility of radioactivity in her breast milk. Total body gamma-ray measurements of the infant indicated ingestion of 82.5 muCi Tc-99m (corrected for effective T 1/2), while ingestion calculated from gamma-ray measurements of serial milk samples was 75.6 muCi. The single organ radiation dose for the thyroid as the critical organ was 300 mRad, whereas that to the total body was 12 mRad (values derived from 82.5 muCi determined by whole body counting). Had breast feeding been continued at 4-hr intervals, the total ingested activity would have been 94.8 muCi giving the infant a dose of 380 mRad to the thyroid and 16 mRad to the whole body. Had the feeding been given 1/2-hr after injection 726 muCi would have been ingested, increasing the dose by a factor of 10.


Bone scintigraphy in scurvy.

Bone scintigraphy in scurvy. Scintigraphic bone changes in two cases of scurvy are described, the cause being subperiosteal hematoma. Generalized increased uptake was shown in the affected femur at an early state of the disease. At a late stage, marked uptake both in the femoral shaft and surrounding tissue was seen causing scintigraphic appearance of widened ("club-shaped") femur.


Ga-67 and Fe-59 distributions in mice.

Ga-67 and Fe-59 distributions in mice. Tissue distributions of i.v.-injected Ga-67 citrate and [59Fe] ferric citrate were measured in normal mice and in lymphoid-tumor hosts. The study arose out of previously reported tissue-culture work showing marked transferrin stimulation of Ga-67 and Fe-59 uptakes by cultured cells from mouse lymphoid tumors. In vivo, however, no obvious correlation was found between Ga-67 and Fe-59 tissue distributions; indeed, Ga-67 showed high affinity for tumor tissue and low affinity for hemopoietic tissues, while for Fe-59 the reverse applied. Taken together, these comparisons of kinetics and distributions for Ga-67 and Fe-59 suggest that a tissue's avidity for Ga-67 is strongly influenced by other factors besides the cell population's capacity for transferrin interactions.


Performance evaluations of recent wide field scintillation gamma cameras. Performance characteristics of four recent wide field scintillation gamma cameras were evaluated for 140-keV gamma imaging. Parameters measured included intrinsic spatial resolution, energy resolution, uniformity and linearity distortion, and count-rate capability and its influence on the spatial resolution. The system performance of the cameras was compared with representative parallel-channel collimators in terms of spatial resolution and relative sensitivity. Visual imaging comparisons of each camera system were performed by taking images of Rollo phantom containing four different lesion sizes, with four different contrast ratios, for equal imaging time.


Subcutaneous isoproterenol: a convenient rat model for early detection of myocardial necrosis. The uptake of Tc-99m pyrophosphate was studied in rat myocardial lesions produced by a single subcutaneous injection of isoproterenol (10--50 mg/kg of body weight). The uptake in the whole heart of treated rats is directly proportional to the isoproterenol dose. The Tc-99m PPi uptake measured at various times after lesion initiation parallels the myocardial calcium concentration changes. This model is useful for screening radiopharmaceuticals, and may also be suitable for studying early uptake in myocardial infarcts.


A simple way of obtaining a composite video output signal from the GAMMA-11 computing system. Many departments of nuclear medicine are currently using the GAMMA-11 computer to process clinical images. Often practitioners would like to display the output pictures on conventional cathode-ray monitors that they already have. Some may want to record the images on a video tape recorder. Both of these devices require a composite video signal, which the computer does not provide. Such a signal can be obtained, however, by combining two signals that the system does produce. A number of relatively complicated systems for doing this have been suggested. The desired result can be obtained, however, by using two ten-cent resistors in the simple circuit described in this paper.


A field procedure for the quantitative assessment of nuclear imaging cameras. Techniques developed for the quantitative assessment of gamma cameras are described. The performance parameters discussed include energy resolution, intransic line spread function, uniformity, and extrinsic line spread function. In addition to describing the equipment used and indicating methods used in analyzing data, some of the potential problems in interfacing multichannel analyzers to gamma cameras are discussed.


Improved computer definition of regions of interest by using a double-cursor method. In the computer analysis of radionuclide studies it is often necessary to define a region of interest (ROI) over an organ or part of an organ. The entire organ boundary is not always apparent on a single image. A method for combining the information from two images in entering the ROI has been developed. It is based on the use of a double cursor that moves simultaneously over both images. Programming was done using special FORTRAN-callable subroutines existing in our system for access to the display. The method is now in routine use for the definition of the left-ventricular ROI during processing of radionuclide cardiac studies.


The effects of meal-feeding at different times of the day on daily changes in serum insulin, gastrin and liver enzymes in the rat. Restricted feeding at two distinct times of the day was associated with different adaptive responses in rats. Animals meal-fed from 1400 to 1800 hours for 6 days demonstrated feeding-cued circadian rhythms in liver weight and in liver transaminase and lactic dehydrogenase enzyme activities. Daily fluctuations in the levels of blood immunoreactive insulin and gastrin were also found to be cued by food intake. By comparison, rats fed from 0700 to 1100 hours for 6 days exhibited altered liver function and blood immunoreactive gastrin patterns. It is suggested that meal-feeding in rats is associated with certain adaptive responses which are dependent upon the timing of the meal. The observed metabolic alterations consequent to meal-feeding are much more apparent in morning-fed than in afternoon-fed animals.


Effects of essential amino acid deficiencies on syngeneic tumor immunity and carcinogenesis in mice. The present study was designed to evaluate in a syngeneic system the longterm effect of dietary reduction of each of three essential amino acids on carcinogenesis with methylcholanthrene (MCA) and immunity to a transplanted MCA tumor. Inbred mice were provided a standard amino acid diet or a diet deficient in isoleucine, leucine, or phenylalanine-tyrosine. In the carcinogenesis experiment, MCA pellets were implanted in each mouse and weekly records were maintained of body weight, tumor incidence, tumor size, and death rate. Mice in the immunity study were inoculated with syngeneic tumor cells; tumors were excised when the largest tumor in the control group reached 12 mm and each animal then received a second challenge of tumor cells. The available data suggest that (1) restriction of the selected amino acids does not inhibit chemical carcinogenesis with MCA, (2) phenylalanine-tyrosine deficiency may actually enhance chemical carcinogenesis with MCA, and (3) selected essential amino acid deficiencies do not enhance immunity to a transplanted MCA tumor.


Relationship of level and type of dietary fat to fetal and maternal rat lipogenesis and lipid deposition. Pregnant rats were pair-fed isoenergetic diets with varying fat content and varying fatty acid compositions to determine if manipulation of the maternal diet would affect fetal lipid metabolism. A mixture of tallow and lard replaced cornstarch on an equal-energy basis so that fat supplied 5 to 65% of the metabolizable energy. Fat content of the maternal diet did not affect fetal weight or fetal body composition. No differences in fetal liver fatty acid synthetase (FAS), glucose-6-phosphate dehydrogenase (G6PD) activities or rate of in vivo fatty acid synthesis were noted. In vivo fatty acid synthesis was greater in fetal liver than maternal liver. Dietary manipulation did not affect in vivo fatty acid synthesis in either fetal or maternal liver. Maternal liver FAS and G6PD activities were generally greater than fetal liver FAS and G6PD activities. These enzyme activities were decreased in maternal livers when the high-fat diet was fed. A sudden decrease in food consumption 24 hours before killing may explain the apparent inconsistencies in enzyme activities and fatty acid synthesis rates. The results of this study indicate that the level of fat in the maternal diet has no effect on the amount of lipid accumulated in fetal tissues or fetal lipogenesis.


An interaction between zinc and vitamin A in pregnant and fetal rats. A possible interaction between zinc and vitamin A metabolism was studied in pregnant rats. Rats were depleted of vitamin A by feeding retinoic acid during growth. At mating, they were fed diets containing 100, 9, or 0.5 microgram/g zinc and were given orally 400, 8, or 0 microgram/kg body weight/day of retinyl palmitate. Low intake of zinc, but not of vitamin A, caused maternal body weight gain, placental weight, and fetal weight all to be low. The number of implantation sites affected and the proportion of fetuses malformed were dependent on intake of both zinc and vitamin A, and there was a significant interaction between these nutrients in regard to both of these parameters. In maternal as well as in fetal animals, plasma and liver zinc concentrations were low in groups fed low levels of zinc, but not in those given low vitamin A. Liver vitamin A values were affected by vitamin A intake but not by dietary zinc concentration. However, plasma vitamin A concentration in both maternal and fetal animals was significantly reduced by low intake of either zinc or vitamin A. There was a significant interaction between these two nutrients in regard to plasma vitamin A. These data indicate an interaction between zinc and vitamin A metabolism possibly at the level of vitamin A mobilization from the liver.


Zinc, nitrogen, copper, iron, and manganese balance in adolescent females fed two levels of zinc. The effect of feeding two different levels of zinc (Diet Z11.5 and Diet Z14.7) on zinc, nitrogen, copper, iron, and manganese balances was determined in 11 girls, 12.5 to 14.2 years, during a 30-day period. Diet Z11.5 provided 11.32 or 11.64 mg zinc daily, levels similar to that determined previously to be consumed by average adolescent females. Diet Z14.7 provided 14.52 or 14.84 mg zinc daily. These levels were just slightly less than the Recommended Dietary Allowance for zinc. When fed Diet Z14.7, subjects lost significantly more zinc in their feces than when fed Diet Z11.5. Regression analyses were applied to the zinc balance data from this study and a previous study with adolescent females. By extrapolation, a dietary intake of 11 mg zinc daily was estimated to compensate for fecal and urinary zinc losses of the average girl in these studies. The standard error of the estimate was 2.18 mg zinc daily. Nitrogen excretion and retention were unaffected by the variations in zinc intake. Copper excretion in the feces was significantly increased when subjects were fed Diet Z14.7 rather than Diet Z11.5. Manganese and iron fecal losses were also significantly correlated to zinc fecal losses.


Enzyme overshoot in starved-refed rats: role of the adrenal glucocorticoid. Intact and adrenalectomized (ADX) rats were starved for 48 hours and refed a 65% glucose diet for 48 hours. Isotonic saline or 8 azaguanine (8AZ) and/or glucocorticoid was administered to the animals during the refeeding period. The typical enzyme overshoot response to refeeding was observed in the intact rats and in the ADX rats given hormone replacement. No overshoot was observed in ADX rats without hormone replacement or in the intact or in hormone treated ADX rats injected with 8AZ. These results suggest that glucocorticoid is involved in the genesis of the enzyme overshoot response to starvation-refeeding, perhaps through an effect on de novo RNA synthesis.


Taurine deficiency in the kitten: exchange and turnover of [35S] taurine in brain, retina, and other tissues. Kittens fed a purified diet containing partially-purified casein as the source of protein become taurine-deficient and develop retinal degeneration. The present studies report the exchange and turnover of taurine in different areas of brain, retina and other tissues and fluids of control and taurine-deficient kittens. The various tissues and fluids have different rates of exchange and different half-lives of taurine; taurine deficiency causes a range of changes in these parameters. Generally, tissues and fluids from taurine-deficient kittens accumulated more [35S] taurine and had a longer half-life of taurine than tissues and fluids from control kittens. Nine areas of brain were studied and, of these areas, olfactory bulb had the greatest concentration of taurine. Olfactory bulb resisted taurine depletion to a greater extent than other areas; and, in contrast to other areas of brain, in taurine-deficient kittens, it accumulated [35S] taurine for most of the experiment. Retina resisted taurine depletion and, in taurine-deficient kittens but not in control kittens, it accumulated [35S] taurine throughout the experiment. The amount of taurine conjugated to bile acids was unchanged by the taurine depletion, but the kinetic behavior was altered and was similar to that of retina. The results provide support for the suggestion that, in the kitten at least, taurine is most important for the functions of bile and retina and that taurine depletion affects retina before bile. Taurine may have special importance in olfactory bulb but not necessarily in other regions of brain.


Calcium-binding protein and kidney 25-hydroxycholecalciferol-1-hydroxylase activity in turkey poults. A vitamin D-dependent calcium-binding protein (CaBP) has been found in the intestinal mucosa of turkeys (Meleagris gallopavo). This protein is similar, if not identical, to the corresponding one found in the intestine of the chicken (Gallus domesticus). The concentration of intestinal CaBP in the intestine of cholecalciferol-fed turkey poults was twice that found in the intestine of the domestic chicken of parallel age. Dietary calcium or phosphorus restriction resulted in a significant increase in intestinal CaBP. This increase was less pronounced than that obtained in chickens. The relationship between duodenal CaBP and dietary calcium appears to be linear. Cholecalciferol (vitamin D) deficiency or dietary calcium, but not phosphorus, restriction resulted in an increase of kidney 25 hydroxycholecalciferol-1-hydroxylase activity in vitro. The values of activity obtained in turkeys were higher than those obtained under the same experimental conditions in chicks. Bone ash was reduced by dietary calcium, phosphorus or cholecalciferol restriction. Plasma inorganic phosphorus was lower in either cholecalciferol- or phosphorus-restricted turkeys. Plasma calcium was significantly higher in the phosphorus-restricted turkeys than in the calcium-restricted or control turkeys.


Dietary niacin requirements for channel catfish. Channel catfish fingerlings were fed purified diets containing five levels (0, 25, 50, 100, and 150 mg/kg) and six levels (0, 5, 10, 25, 50, and 100 mg/kg) of supplemental niacin in 20 and 12 weeks feeding studies, respectively. The dietary niacin level required to provide maximal growth in rapidly growing channel catfish fingerlings was found to be approximately 14 mg/kg of diet. Fish fed unsupplemented diets (niacin content of 1.6 mg/kg diet) demonstrated poor growth, anemia, skin and fin lesions and hemorrhages, exophthalmia and total mortality in 20 weeks. Mortality and gross deficiency signs were prevented by 11.6 mg niacin/kg diet and anemia was prevented by 6.6 mg/kg. No histological abnormalities were observed in the heart, hepatopancreas, kidney, lateral muscle, gastrointestinal tract and gill tissues of deficient fish.


Riboflavin requirement of channel catfish fingerlings. Channel catfish fingerlings were fed purified diets containing five levels (0, 20, 40, 80, and 120 mg/kg) and six levels (0, 3, 8, 20, 40, and 80 mg/kg) of riboflavin in separate 20 and 12 week feeding studies. The dietary riboflavin level required to provide maximal growth in channel catfish fingerlings was found to be approximately 9 mg/kg of diet. All fish fed unsupplemented diets (riboflavin content less than 0.1 mg/kg diet) demonstrated a short body dwarfism which was the result of arrested longitudinal growth of the vertebrae. This abnormality did not occur in groups fed 3 mg/kg or higher levels of riboflavin. No histological abnormalities were recognized in the liver, kidney, lateral muscle, gastrointestinal tract, gills, or bones of deficient fish.


Effects of proteins and their corresponding amino acid mixtures on nitrogen balance and body composition in the growing rat. The efficiencies of nitrogen utilization from intact proteins (casein, gluten, soybean, egg albumin) were compared to that of the respective synthetic amino acid mixtures. Food intake, growth, NER (nitrogen efficiency ratio), (Nitrogen retained/Nitrogen intake) X 100, BV (biological value), TD (true digestibility), liver weight and body composition were estimated on growing rats. Rats fed amino acid mixtures simulating casein, egg albumin and soybean consumed more food and showed more rapid growth than rats fed the intact proteins. Differences in nitrogen utilization and body composition were occasionally observed between the respective intact protein and amino acid mixtures but were in most cases not significant. It is concluded that nutrition with intact proteins cannot be assumed to be equivalent to nutrition with the corresponding amino acid mixture. However, general differences between the two types of feeding regimens were not obvious since the results were influenced by factors such as the amino acid composition of the protein and the amino acid mixture as well as the methodology used for nutritional evaluation. (Nitrogen retained/Nitrogen intake) X 100 and BV but not NER of an amino acid mixture formulated according to a commercial elementary diet was found to be low compared to casein.


Effects of a protein deprived diet on the hepatotoxicity, and the DNA synthetic, mitogenic, and immunological actions of microbial lipopolysaccharides in the rat. Rats fed an 18% casein (Cs) or a protein deprived diet (PD) for 8 weeks received injections of Escherichia coli lipopolysaccharides (LPS) in both hind foot pads. While these injections were tolerated in Cs rats, about 50% of PD rats died after 1 or 2 days as a result of a massive necrosis of the liver. To a large extent these lesions were prevented by cortisone. Three days after injection of LPS, Cs rats exhibited a hypertrophy of the popliteal lymph nodes (PLN) and spleen, as well as a drastic increase in DNA synthesis in DNA synthesis in the PLN. Mitotic indices did not increase. The DNA synthetic responses to PLN in the surviving PD rats were much lower than in Cs animals, but a sharp rise in DNA synthesis and mitotic activity occurred in the spleen. The comparison with the effects of LPS in cortisone-treated rats showed that both cortisone-sensitive and -resistant cells participated in PLN activation in rats fed both diets, but that only cortisone-resistant lymphocytes entered mitosis in the spleens of PD rats. LPS also provoked a sharp drop in both DNA synthesis and mitosis in the thymus, probably due to a stress effect, since only cortisone-sensitive thymocytes were involved. In a second experimental series, immunological tests (Rosette-forming cells, Plaque-forming cells, serum hemagglutinin titers) were performed 7 days after intraperitoneal injection of LPS. The responses were not significantly different in Cs and PD rats. This is in contrast with the protein deficiency-induced depression of thymus-dependent humoral immunity.


Schistosoma mekongi sp. n. from man and animals, compared with four geographic strains of Schistosoma japonicum. Schistosoma mekongi sp. n. is described from man and animals in Cambodia. It is compared to 4 geographic strains of Schistosoma japonicum. It differs from S. japonicum in the size of embryonated eggs, in the length of the prepatent peroid in the mammalian host, and in its utilization of a different snail host. The relative usefulness of conventional morphologic criteria in the differentiation of Asian schistosomes is discussed.


Changes in tegumental surface during development of Schistosoma mansoni. The tegumental surface of immature Schistosoma mansoni was studied with the scanning electron microscope. The surfaces of immature males and females bear no resemblance to that of adult worms and are characterized by having many tegumental folds. The tegumental surfaces of immature males and females are similar, and the dorsal and ventral surfaces of the male are similar before formation of the gynecophoral canal. Transition of the tegumental surface from the juvenile to the adult form begins after worms are in copula and have grown to several millimeters in length.


Parasitism as a factor (?) in single strandings of southern California cetaceans. From 1970 to 1976 a total of 91 cetaceans was examined for parasites and associated pathology. Sixty of the animals were found stranded along a 100-mile section of southern California coastline while 31 were taken at sea. Parasites from 5 species of cetaceans are reported along with their possible role as a contributing factor in stranding behavior.


Studies on the reproductive system of Philophthalmus gralli using techniques of transplantation and autoradiography. Adult Philophthalmus gralli exposed in vitro to 3H-thymidine for 6 hr showed label on autoradiograms over actively dividing cells in the testes, ovary, and vitellaria. In worms transplanted to chicks, oogonia became primary oocytes within 4 days and these were first found enclosed in newly formed eggs by 12 days. Tertiary spermatogonia at the periphery of the testes developed into sperm by 144 hr and were found in the serminal vesicle by 168 hr. Vitelline cells required 96 hr to travel from gland areas to become incorporated into eggs. In adults labeled in vitro for 1 hr with 3H-tyrosine and transplanted singly to chicks, only 2 of 28 self-inseminated. Labeled worms transplanted with unlabeled worms never self-inseminated but cross-inseminated with approximately 40% of the available worms. Transplanted worms localized in the chick's orbit in 3 microhabitats. In only 1 of 21 experiments did a labeled worm inseminate unlabeled worms outside of the microhabitat where it was found.


Immunoglobulins on the surfaces of tetrathyridia of Mesocestoides corti Hoeppli 1925 (Cestoda), from laboratory infections of ICR mice. 7Sgamma2b antibody was detected, by fluorescein labeled antibodies, on the body surfaces and wall of excretory bladder of tetrathyridia of M. corti removed from the peritoneums of 5--24-week laboratory infections of ICR/TIMCO mice. 7Sgamma1, 7Sgamma2a, 7Sgamma3, IgM, IgA, and C3 were not found by use of the same techniques. Tetrathyridia maintained in culture medium to which pooled normal mouse, infected mouse, and horse (control) serums containing all known classes and subclasses of immunoglobulins had been added showed only mouse 7Sgamma2b on their surfaces and wall of the excretory bladder, and then only when incubated in pooled serum from infected mice. No other mouse immunoglobulin classes or subclasses were found attached to the worms, nor was any reaction obtained from tetrathyridia incubated in culture medium alone, normal mouse serum, or horse serum. This suggests a highly selective nonspecific absorption of 7Sgamma2b, or more likely demonstrates the specificity of the antibody for the parasite surfaces and wall of the excretory bladder. The possibility that 7Sgamma2b may be acting in an enhanceing mode is discussed.


Studies on sylvatic echinococcosis. V. Factors influencing prevalence of Echinococcus multilocularis Leuckart 1863, in red foxes from North Dakota, 1965--1972. A total of 1,153 red foxes, Vulpes vulpes, was examined for strobilae of Echinococcus multilocularis from 2 geographic regions in North Dakota during 1965 through 1972. Echinococcus multilocularis was found in 184 (16%) of these foxes. The data including date and location of collection, age and sex of the host, and presence or absence of the cestode were used to assess the relative influence of collection interval (sampling period), climatic season, geographic location, and age and sex of the host on the prevalence of the adult cestode. The rate of infection varied significantly with collection interval, which was probably attributable to annual changes in the overall environment. Seasonally, the highest prevalences were observed during summer (32.4%) followed by spring (25.3%), autumn (13.7%) and winter (6.4%). Differences in prevalence between adult and juvenile foxes and that between male and female foxes were not significant. A 3-factor analysis of variance showed the order of importance of the significant variables to be collection interval, season, and the interaction of collection interval and season. A 4-factor ANOVA, which in addition to the above variables included geographic location, showed that the collection interval-location interaction had significant effects on prevalence. Also, evidence is presented that suggests that density of the definitive host may in part be responsible for annual fluctuation in prevalence.


Modification of immune competence by parasitic infections. I. Responses to mitogens and antigens in mice treated with Trichinella spiralis extract. Spleen cells from mice pretreated with a Trichinella spiralis extract (TsE-mice) showed severe depression of the response to lipopolysaccharide (LPS) and to concanavalin A (Con A), slight depression to phytohemagglutinin (PHA) and normal response to tuberculin purified protein derivative (PPD) as compared to saline-pretreated controls. Mice pretreated with bovine serum albumin (BSA-mice) revealed greatly reduced responses to LPS, somewhat reduced response to Con A, and normal responses to PHA and to PPD. Only TsE-mice showed significant reduction in the number of rosette-forming cells and of direct and indirect plaque-forming cells (DPFC and IPFC). BSA-mice exhibited some reduction of the DPFC only. Direct hemagglutinating (HA) titers were equivalent in the 3 groups after immunization with sheep erythrocytes but facilitated HA titers were depressed in TsE-mice. The total number and the number of viable cells were similar in the spleens of all animals. TsE treatment causes a reduction in the number of T1 lymphocytes and an inhibition of the late differentiation of B cells in the spleen. Suppressor T-cells apparently play a major but not exclusive role in T. spiralis-induced nonspecific immunodepression.


Immunization of pigs against experimental Ascaris suum infection by feeding ultraviolet-attenuated eggs. Pigs fed Ascaris suum eggs attenuated by short-wave ultraviolet radiation developed a resistance to challenge infections that varied according to the protocols used. Two doses of eggs irradiated at total exposures (ET) of 150 muW-min/cm2 resulted in a reduction of adult worm burden in 3 groups challenged with 50, 100, or 500 eggs by 45, 35, and 49%, respectively. However, these results were not statistically significant (P greater than 0.05). Three other groups were fed eggs as follows: Group 1, 3 doses irridated at ET's of 150, 150 and 150; Group 2, 3 doses irradiated at ET's of 150, 150, 100; and Group 3, 3 doses irradiated at ET's of 150, 100, and 75. All of these regimens provided significant protection: Group 1 (P less than 0.02), Group 2 (P less than 0.05), Group 3 (P less than 0.001). An analysis of the lengths of worms recovered showed that in controls fed varying doses of eggs, worm sizes were inversely related to the number of eggs in the challenge dose. Measurements of worms from vaccinated animals showed that 23 of 116 adult worms recovered were probably survivors of one or more of the vaccinating doses. A ratio of 18 female to 5 male worms indicated that males are more susceptible to ultraviolet radiation than females.


Corollostrongylus hypsiprymnodontis gen. et sp. n. (Nematoda: Strongylidae) from the rat-kangaroo, Hypsiprymnodon moschatus (Marsupialia). Corollostrongylus hypsiprymnodontis (Nematoda: Strongylidae) is described from the intestine of the Musk rat-kangaroo, Hypsiprymnodon moschatus Ramsay 1876, from Atherton, Queensland, Australia. The new genus is distinguished from other genera of the Strongylidae by the dorsal deviation of the head, the oval mouth opening, and the dorsal ray which given off 2 small lateral branches before dividing into 2 long parallel rays.


Extraintestinal stages fo Isospora ohioensis from dogs in mice. The development of Isospora ohioensis was studied in mice by feeding tissues of mice inoculated with oocysts to coccidia-free dogs and by the examination of mesenteric lymph nodes using light and electron microscopes. Extraintestinal organs of mice became infectious to dogs within 1 day after ingesting oocysts and remained infectious for at least 211 days after inoculation (DAI). Isospora ohioensis sporozoites were found in lymphoreticular cells of mesenteric lymph nodes of mice from 1-374 DAI. Intracellular sporozoites were located in parasitophorous vacuoles. Sporozoites grew from 5--6 to 11--16 micron in length on the 39th DAI but never lost the 2 crytalloid bodies typical for coccidian sporozoites. PAS-positive granules accumulated gradually in intracellular sporozoites with duration of infection in mice. The appearance of parasitophorous vacuoles varied with duration of infection. Beginning with 7 DAI, the vacuole contained a marginal zone of electron-dense material (up to 0.8 micron wide), giving the appearance of a cyst wall or sheath under the light microscope; a true cyst wall was was not found.


Chemosterilization of Dermacentor variabilis Say (Acari: Ixodidae). I. Effects of metepa on the cytology and fertility of males treated as unfed adults. The effects of metepa on the cytology and fertility of male Dermacentor variabilis treated as unfed adults are determined. Evidence of cellular damage is found in testicular areas where actively dividing cells and some enlarging spermatocytes are found. The amount of cellular damage correlates positively to the concentration of the chemosterilant and results in decreases numbers of spermatids. In crosses of treated males to untreated females, resulting egg masses hatch normally; however, the percentage of females producing egg masses that hatch is reduced.


The value of circular myotomy for esophageal atresia. The joining of widely separated proximal and distal esophageal segments in esophageal atresia remains a challenging problem. Livaditis introduced the operation of circular myotomy as an effective means of bridging such a wide gap. Three babies with esophageal atresia were successfully treated in this manner at the Hospital for Sick Children, Toronto, during the 1st 6 mo of 1976. No alterations in blood supply of the upper esophageal pouch were observed, and elongations of at least 1 cm per myotomy were obtained. No unusual postoperative radiographic observations were noted. Our small clinical experience suggests that circular myotomies aid in reducing long esophageal gaps in some infants with esophageal atresia, thus permitting primary esophageal anastomosis.


Congenital esophageal atresia with tracheoesophageal fistula in identical twins. This is a report of the seventh case of esophageal atresia in both members of a pair of identical twins.


The flaccid trachea and tracheoesophageal congenital anomalies. The patient with an esophageal atresia associated with a distal tracheoesophageal fistula, is often found to have an abnormally soft trachea. The use of contrast material as an aid in the diagnosis of this congenital anomaly demonstrates radiologically the compressive effect that a dilated and hypertrophied proximal esophageal pouch has on the trachea of the newborn. It is postulated that this chronic compressive force plays a part in retarding the development of the trachea during fetal life. The important decompressive effect of a distal tracheoesophageal fistula allowing nonphysiologic escape of lung fluid, supplements this effect. Attention is drawn to the fact that tracheal compression plays an important part in the respiratory distress seen in these patients, both before and after surgical correction of the tracheoesophageal anomaly.


A complication of continuous upper pouch suction in esophageal atresia. The use of a plastic sump catheter for continuous suction of the blind upper pouch in esophageal atresia has been widely accepted since the method was first described. The following case illustrates a complication which resulted from the use of such a catheter, namely, perforation of the upper pouch.


An improved method for retaining retrieval line in children undergoing repeated esophageal dilatation. Children undergoing repeated retrograde esophageal dilatation using gastrostomy introduced Tucker dilators must retain a retrieval line between dilations. Generally, the line is tied into a loop coursing through the esophageal lumen and exits at the gastrostomy and nose. This technique, while effective in maintaining the line in situ, is fraught with hazards of chronic erosion at both exits sites, with significant cosmetic deformity, necessitated by the taped external line and, in the pediatric age group, with frequent harassment by peers and siblings pulling the exposed line. We have modified this technique, leaving the line looped around the nasal septum with both ends extending down the esophagus into the stomach where they are tied to the tip of the gastrostomy catheter. This results in an almost completely internalized line that is protected, well tolerated, and easily retrieved for subsequent use with the dilators.


Acquired tracheoesophageal fistula.

Acquired tracheoesophageal fistula. This is a case of an acquired tracheoesophageal fistula induced by a large foreign body in a 5-yr-old child. The foreign body, a large plastic ear from a doll, was lodged in the esophagus and its presence remained unknown for weeks, until tracheoesophageal fistula actually developed. The foreign body was removed endoscopically; after the child was given intravenous nutrition and the infection was brought under control, the communication was divided and repaired.


Endesophageal resection of short benign strictures of the esophagus. A relatively simple operation for the treatment of short esophageal strictures that do not respond to dilatations has been described. This operation was successfully carried out at all levels of the esophagus. The strictures treated were caused by lye burns, peptic esophagitis and previous anastomoses.


Prognosis of uncorrected biliary atresia: an update. In order to provide a baseline for comparison with the results of the Kasai hepatic portoenterostomy, follow-up information was obtained for 89 infants who underwent surgical exploration alone for biliary atresia from 1956 through 1975. Of these patients, one is apparently cured, one is alive with liver failure, three are lost to follow-up and 84 are dead. The rate of apparent cure among patients with follow-up was 1.1%. The average age at death was 12 mo, the mean 10 mo. During this same period, nine patients were operated upon for neonatal biliary obstructions other than biliary atresia, and five are apparently cured. Reported apparent cure rates after the Kasai procedure or one of its variations, while not good, still compare favorably with the cure rate of unoperated patients.


Serum and erythrocyte acetylcholinesterase activity in Hirschsprung's disease. Acetylcholinesterase activity was measured in the serum and erythrocytes from 22 children. The 12 patients in whom the diagnosis of Hirschsprung's disease was confirmed, had a significantly higher concentration of enzyme in both serum and erythrocytes than the 10 children in whom the diagnosis was excluded. This systemic manifestation, may prove of value in the diagnosis of Hirschsprung's disease.


Accuracy of the manometric diagnosis of Hirschsprung's disease. In a 3-yr period, 229 examinations were carried out in infants and children. These were sub-divided into five groups according to age. There were 10 false positive and 8 false negative results, an overall not unreasonable record of 7.8% errors. However, in the neonatal group, there were as many as 26% errors and thus the test in this group was considered to be highly inaccurate. The older the infant or child, the less errors in diagnosis occurred. Possible reasons for errors are pointed out and comparisons are made with other series.


Hirschsprung's enterocolitis, prostaglandins, and response to cholestyramine. An infant with Hirschsprung's enterocolitis developed a fulminant secretory diarrhea unresponsive to all conventional therapy until cholestyramine was administered. A 12-fold decrease in prostaglandin E (PGE) levels in the colostomy fluid was documented in response to cholestyramine therapy. It is postulated that increased PGE activity, enterotoxin, and bile acid malabsorption may be involved in the enterocolitis of Hirschsprung's disease.


Ovarian teratomas in early childhood.

Ovarian teratomas in early childhood. The ovary is second only to the sacroccygeal area as the commonest anatomic site for the occurrence of teratomas (including dermoid cysts) in infancy and childhood. While virtually all sacrococcygeal teratomas are present at birth or appear within the first 24 mo of life, ovarian teratomas are quite rare within the first 24 mo of life and seldom appear before 6 yr of age. Teratomas comprise half the surgically significant lesions of the ovary in infancy and childhood and carry a mean malignancy incidence of approximately 14% in this age group. Seven cases of ovarian teratoma in the first 2 yr of life have been reported. All of these have been seen in the second 12 mo of life. They differ from those occurring after 2 yr of age in the lesser incidence of abdominal pain, the higher incidence of an abdominal mass and the absence of reported malignancy.


Transcervical thymic biopsy in children with immunodeficiency. To more fully characterize immunodeficiency states, thymic biopsies add useful information. The transcervical technique is simple and does not require a sternal-splitting procedure. The thymus was much larger than anticipated in 12 of 12 cases so far biopsied, including six cases of severe combined immunodeficiency. A sample of 2-3 gm was readily removed. A slight wound infection was encountered in only one instance; no generalized septic episode resulted.


Cystic fibrosis in a black infant: presentation with meconium ileus and volvulus. This is a case report of meconium ileus complicated by intestinal volvulus and infarction in a black infant.


Hyperchloremic acidosis in an infant with imperforate anus and rectourethral fistula. A case of hyperchloremic acidosis in an infant with imperforate anus and rectourethral fistula, showing lethargy, tachypnea, vomiting, and dehydration, is reported. Surgical correction by abdominoperineal pull-through and division of the rectourethral fistula was performed after doing a cystocutaneostomy to eliminate the diversion of urine into the rectum.


Transomental strangulation.

Transomental strangulation. A case of transomental strangulation in an 8-yr-old boy is presented with a review of the pertinent literature. The clinical presentation was that of an intestinal obstruction. A gastrografin study indicated the necessity of immediate surgery. Etiologic aspects and nomenclature controversies are briefly discussed.


Positive evaluation of stressful experiences. Two studies were conducted to test the hypothesis that the more stressful an experience is, the more positively it will be evaluated. Stressfulness was manipulated in the two studies by means of threat of shock, and both self-report and physiological measures of stress indicated that these manipulations were highly successful. In both studies subjects who were exposed to the more stressful situation evaluated their experience as significantly more worthwhile and somewhat more interesting than did subjects exposed to the less stressful situation. Furthermore, as expected, subjects did not like the high stress experience more than the low stress experience. Implications and qualifications of these findings are discussed.


The interactive effects of locus of control and situational stress upon performance accuracy and time. The present paper sought to clarify the conceptual relationship between expectancy for personal control, stress, and behavioral reactions to stress. Expectancy for control was assessed as a personality characteristic of internal control; stress was experienced as strong environmental interruptions, disturbances and unpredictable obstacles encountered during the performance of assigned tasks. Subjects were junior high school aged students who attempted to complete three academic type tasks during one of two levels of stress or a base line, no stress, condition. Analyses of the data included: (a) internal subjects were capable of sustaining task performance under high stress, but external students experienced performance decrements as stress increased; (b) time to complete the mathematics task reflected a facilitating effect of stress for internals but a debilitating effect for externals; (c) performance differences between internal and external students, in the absence of differences in reported anxiety, could be attributed to the stronger reward expectancies possessed by the internal individual. Interpretation of the data suggested an interactive relationship between type of stress (threat to ego vs. threat to instrumental performance) and expectancy for control in the influencing of behavior reactions to stress.