The physico-chemical characterization of bovine ephemeral fever virus as a member of the family Rhabdoviridae.

This study of the physico-chemical properties of bovine ephemeral fever virus was initiated to establish whether or not it should be classified as a rhabdovirus. In contrast to the regular bullet-shaped morphology of some rhabdoviruses the virus particles are often cone-shaped or slight variants from bullet-shaped. The virion contains single-stranded RNA sedimenting at 42S and six proteins with mol. wt. of 164, 101, 64, 53, 43 and 29 x 10(3). The protein P101 is located on the surface of the virus and is glycosylated. It is removed by treatment of the virus particles with trypsin. Protein P64, the nucleoprotein, was found to be a phosphoprotein, like the N protein of rabies virus, whereas in vesicular stomatitis virus NS is the phosphorylated protein. Virus harvests contain defective-interfering particles. The particles are short cone-shaped forms about one-third the length of the infectious virion and similar in morphology to defective-interfering particles of vesicular stomatitis virus. These particles interfere with the replication of bovine ephemeral fever virus but not with the Indiana serotype of vesicular stomatitis virus. They contain single-stranded RNA sedimenting at 18 to 20S. The particles appear to have a protein composition identical to that found in the virus particle. The physico-chemical properties of bovine ephemeral fever virus justify its inclusion in the family Rhabdoviridae. The protein composition differs in detail from that found for vesicular stomatitis and rabies viruses, but is similar to that found for Obodhiang and kotonkan, two rabies serogroup viruses isolated from insects in Africa.


Behavioral changes in hospitalized acute schizophrenics. An ethological perspective.

Ethological techniques were employed to monitor the behavior of hospitalized patients suffering from acute schizophrenic disorders during the first 4 weeks of hospitalization. Two groups were studied: a) patients whose clinical condition markedly improved (N = 3); and b) patients whose clinical condition showed little or no improvement (N = 3). Method, observational procedures, and the taxonomy of behaviors recorded closely followed previous research of the authors. Data are analyzed in terms of behavioral diversity, the frequency of individual behaviors, and grouped behaviors. Compared to unimproved patients, improved patients showed less behavioral diversity for pathological behaviors and a reception of more social behavior. An analysis of individual behaviors reveals differences between the two groups. Issues relating to the utility of observational methodology and differences between chronic vs. acute schizophrenic populations are discussed.


The Galveston Orientation and Amnesia Test. A practical scale to assess cognition after head injury.

The Galveston Orientation and Amnesia Test (GOAT) was developed to evaluate cognition serially during the subacute stage of recovery from closed head injury. This practical scale measures orientation to person, place, and time, and memory for events preceding and following the injury. The distribution of test scores in 50 patients who had recovered from a mild closed head injury was used to define the range of variation in performance and to analyze the effects of demographic factors. In a validity study of 52 closed head-injured patients, the duration of impaired GOAT scores was strongly related to the acute neurosurgical ratings of eye opening, motor responding, and verbal responding on the Glasgow Coma Scale. Duration of post-traumatic amnesia, as defined by the persistence of defective GOAT scores, was longer in patients with computed tomographic evidence of diffuse or bilateral brain injury as compared to cases with focal unilateral lesions. Serial GOAT scores were also predictive of long term level of recovery. Review of the brief cognitive test literature disclosed that several techniques have adequate validity data substantiating their use in the detection of dementia in geriatric, psychiatric, and medical populations. Recommendations for the clinical application of the various brief cognitive tests are discussed.


Measurement of thinking dysfunction. An empirical study.

This investigation is concerned with the development of a practical method for assessment of thought disorders. A review of eight major textbooks and four review articles revealed 37 different terms used to describe the components of thought disorders. Because of overlap of meanings or ambiguous usage, these terms were reduced to 17 discrete terms that could be operationally defined. Twenty-five psychiatrist were surveyed on the appropriateness of the definitions and their relevance to the concept of thought disorder. An average of 83 per cent agreement was obtained, and some of the definitions were modified as a result of the survey. Eight psychiatrists then applied this scale, titled the Thinking Dysfunction Rating Scale, to the evaluation of five videotaped patient interviews. Based on observation of all five patients, interjudge agreement was over 90 per cent for all items of the scale. Analysis of variance showed that the scale significantly discriminated among schizophrenics, patients with organic brain syndromes, psychotic depressives, geriatric depressives, and outpatients. The patterns of scores were found to vary among these five groups. The scale should be helpful for teaching purposes and as a checklist for routine clinical diagnosis.


A comparison of the Halstead-Reitan Neuropsychological Battery and computerized tomography in the identification of brain disorder.

An attempt was made to compare the diagnostic conclusions of the Halstead-Reitan battery with the diagnosis of the computerized tomography (CT) scanner), which has recently created profound changes in neuroradiological practice. Subjects were 45 patients whose neurological diagnosis was used as a criterion for CT, EEG, and three Halstead-Reitan diagnostic statements (Halstead Impairment Index, Rennick Average Impairment Rating, and clinical interpretation). Results indicated no false positive errors with the CT and the highest overall accuracy rate with a clinical interpretation of the Halstead-Reitan tests. The complementary roles of these varied neurodiagnostic methods, which provide different kinds of pertinent neurological information, are stressed.


Arguments against 5-hydroxytryptamine as neurotransmitter in the rabbit retina.

The indoleamine accumulating retinal neurons are visualized only by uptake of exogenously applied indoleamines but lack fluorescence in the normal retina. These neurons have now been studied in the rabbit after pretreatment with L-tryptophan and a monoamine oxidase inhibitor with an improved histofluorescence method based on perfusion with formaldehyde-glyoxylic acid pH 4.5 containing high amounts of magnesium. The method does not, however, reveal any indoleamine fluorescence in the retina. Also, p-chloroamphetamine has no toxic effect on the neurons. Selective inhibitors of the uptake of 5-hydroxytryptamine have a lower inhibitory effect in the retina than in the hypothalamus. A substance other than 5-hydroxytryptamine is therefore suggested to be the transmitter of the indoleamine accumulating neurons.


The pattern of urinary catecholamines and their metabolites in Duchenne myopathy, in relation to disease evolution.

In this report we have tried to determine whether or not catecholamines are involved in the progressive muscular dystrophy. Catecholamines and their metabolites were studied in urines of children with Duchenne disease or other forms of myopathy (limb-girdle and facio-scapulo humeral myopathies). Catecholamine deaminated metabolites were normal in either form of myopathy; in contrast, Duchenne patients, contrarily to other children, eliminated excessive amounts of most amines (catecholamines and methoxylated amines) in relation to age and degree of disease evolution. Our results indicate that catecholamines are not the primary factors involved in the pathogenesis of Duchenne myopathy, but are rather secondary to some disease effects. It is suggested that the high excretion of catecholamines and their methoxylated amine metabolites observed in severely affected Duchenne boys might be related to thermoregulatory process or/and to alterations in some enzymatic systems.


Responses of plasma renin activity and dopamine-beta-hydroxylase to increased intravascular volume.

Circadian variations of plasma renin activity, plasma dopamine-beta-hydroxylase, and urinary aldosterone excretion were measured in man under conditions of high- and low-sodium intake. Plasma renin activity and urinary aldosterone excretion were maximal at 8 a.m. Plasma DBH shows small, biologically insignificant circadian fluctuations. In three subjects on low-salt diets, the values were lower than those in the same subjects on high-salt diets. Expansion of intravascular volume in supine normal volunteers lowered plasma renin and DBH activity, and also resulted in a significant natriuresis. The decline in DBH activity probably reflects a decrease in its release from autonomic nerve endings and thus demonstrates in man an effect of decreasing autonomic activity.


Plasma dopamine beta hydroxylase (D.B.H.) activity in Parkinsonian patients under L-dopa, and 2-bromo-alpha-ergocriptine loading.

Dopamine-Beta-Hydroxylase (D.B.H.)-activity was measured in the plasma of untreated Parkinsonian patients, after tretment with L-dopa and 2-Bromo-alpha-ergocriptine. The findings were compared to the D.B.H.-activity of a matched healthy control group. After L-dopa loading D.B.H.-activity decreased in the Parkinsonian patients by 27.6 +/- 3.1% compared to 16.2 +/- 3.3% (p less than 0.02) in the control group. After 2-Bromo-alpha-ergocriptine laoding the decrease in D.B.H.-activity was 32.6 +/- 4.4% in the parkinsonian patients, and 158 +/- 4.9% (p less than 0.02) in the control group. This reduced D.H.B.-activity after L-dopa loading may reflect an impairment, in the Parkinsonian patients' ability to metaoblize L-dopa. The reduced D.B.H.-activity after treatment with 2-Bromo-alpha-ergocriptine may be explained by a pronounced antagonistic influence of 2-Bromo-alpha-ergocriptine on the presynaptic dopamine receptors, suggesting that presynaptic dopaminergic receptors are involved in Parkinson's disease.


Unsymmetrical C-substituted ethylenediamine platinum coordination complexes: synthesis and activity against mouse leukemia L1210.

A series of new unsymmetrical C-substituted ethylenediamines was prepared. The substituents included branched chain alkyl, cycloalkyl, and phenyl groups. Twenty-eight new platinum compounds were prepared from these diamines and were tested for activity against leukemia L1210. The cycloalkyl substituted ethylenediamines produced especially active compounds. The phenyl-substituted analogs were generally low in activity. The activity of the complexes was compared to aqueous solubility, organic solubility, and amphipathic character. There was good indication that antitumor activity increased as aqueous solubility and hydrophilic character of the molecules increased.


EXAFS studies of the molybdenum center of xanthine oxidase.

EXAFS spectra associated with the K-absorption edge of molybdenum in the desulpho and functional forms of xanthine oxidase and some potential synthetic analogues have been obtained. These data indicate that the immediate environment of the molybdenum is different in the two forms of the enzyme and that desulpho xanthine oxidase resembles that in [MoO2(S2CNEt2)2] and [MoO2(ethylcysteine)2]. The cyanolysable sulphur atom of functional xanthine oxidase is suggested to be tightly bound to the molybdenum at a distance of less than or equal to 2.3 A.


Inverted knee jerk: a neglected localising sign in spinal cord disease.

Two cases are described in which inversion of the quadriceps jerk was observed. It is suggested that the finding of an inverted quadriceps jerk is evidence of a spinal cord lesion at 12, 3, 4 segmental level and has for the lumbar cord the same localising value as the inverted supinator jerk for the cervical cord.


The afferent pupillary defect in acute optic neuritis.

Twenty-two patients with acute optic neuritis were studied by the techniques of infrared pupillometry and visual evoked responses (VER) to pattern reversal. A relative afferent pupillary defect was found in all cases and the magnitude of this defect was found to be related to the amplitude, but not to the latency, of the VER. During follow-up the afferent defect was found to remain persistently abnormal while other methods of clinical evaluation could not demonstrate abnormality reliably. The amplitude of the VER also remained low.


Absence of parasympathetic denervation of the iris in alcoholics.

Forty patients with a history of alcohol abuse were treated with a 2% solution of methacholine to determine the prevalence of iridic parasympathetic denervation. Three (8%) of the alcoholics showed iris constriction of 1.0 mm or more, compared with three (8%) control subjects. In contrast, damage to the iridic parasympathetic nerve supply occurs in approximately 80% of patients with diabetes mellitus as determined by the same pharmacological technique.


Memory in functional psychosis.

Acute schizophrenic, chronic schizophrenic, and depressive patients (20 of each) were compared with normal subjects and six groups of patients with organic brain disease. They were given tests of verbal learning (left hemisphere type function) and pattern recognition memory (right hemisphere type function). All functional psychotics showed impaired memory. Acute schizophrenics were, however, only impaired on the verbal task, suggesting left hemisphere dysfunction, while chronic schizophrenics and depressives were impaired on both tasks, suggesting bilateral dysfunction.


(+)-Nortrachelogenin, a new pharmacologically active lignan from Wikstroemia indica.

A new lignan, (+)-nortrachelogenin (I), and a known compound, daphnoretin were isolated from Wikstroemia indica C. A. Meyer (Thymelaeaceae). The structure of (+)-nortrachelogenin was established as 8(R), 8'(R)-4,4',8'-trihydroxy-3,3'-dimethoxylignan-olid(9, 9') on the basis of spectroscopic evidence and comparison with its enantiomer, (-)-nortrachelogenin. (+)-Nortrachelogenin (I) showed effects on the central nervous system producing depression in rabbits.


Nocardia cerebral abscess: New concepts in diagnosis, management, and prognosis.

Three cases of multiple cerebral nocardial abscess are presented. All were cured by a combination of chemotherapy and surgery, a unique experience. Early detection, appropriate chemotherapy, absence of underlying immune malfunction, and surgically remediable disease are good prognostic indices in cerebral nocardiosis. If other adverse prognostic factors are absent, however, multiple abscess formation does not preclude the possibility of cure. Accurate localisation of nocardia cerebral abscesses by computerised axial tomography is a great help in management if multiple lesions are present.


Intracranial sewing needles: Review of 13 cases.

Three new cases of intracranial sewing needles are reported and are reviewed with 10 other published cases. These needles must have been introduced in infancy before the closure of fontanelles. The intention, at least in most cases, has been infanticide. Except in one case which the mother reported and two cases found at necropsy, the others were diagnosed by skull radiography. Headache and epilepsy were the main symptoms and they often appeared when the patient had reached adulthood. Removal of the needles lessened the symptoms.


Pineal apoplexy.

A case of haematoma in the pineal region is reported in a patient whose initial symptom was subarachnoid haemorrhage. The encapsulated haematoma and surrounding blood clots were removed surgically. Haemorrhage into a pineal cyst may have been the cause of this particular intracranial mass.


Successful removal of an intrapontine haematoma.

A patient with progressive signs and symptoms suggestive of a pontine lesion is described. Intracranial investigations, CAT scan, vertebral angiography, and lumbar pneumoencephalogram revealed a space-occupying lesion of the pons and midbrain. The exact nature of the lesion was not established before the operation. A posterior fossa exploration was performed and a pontine haematoma was discovered and evacuated. The pathological specimen was designated as a cryptic arteriovenous malformation. Preoperative neurological deficits disappeared except for minimal left sixth nerve palsy and mild truncal ataxia.


Locked-in syndrome caused by a solitary pontine abscess.

The clinical and pathological findings in a patient with locked-in syndrome caused by a solitary pontine abscess are reported for the first time. Successful treatment of brainstem abscess rests on early and accurate diagnosis.


Internal carotid artery occlusion caused by giant cell arteritis.

A case of hemiplegia in a 46 year old woman is described. Total occlusion of the right internal carotid artery was discovered at angiography. Because of persistent elevation of the ESR, and characteristic plasma protein abnormalities, biopsy of the temporal artery was carried out and demonstrated the typical features of giant cell arteritis.


Surgical treatment of giant pituitary adenomas.

Multidirectional extension and invasive spread are important features of giant pituitary adenomas. Operability cannot be established merely by determining the size of the most prominent part of the tumour. Detailed radiological evaluation with plain films, computed tomography, angiography, and air studies all contribute to evaluation of the precise anatomy before surgery. In the final decision risks of surgical treatment must be balanced against the patient's age and prospects of long-term useful survival. Unfavourable cases for surgical treatment in our hands were those tumours embedded in the hypothalamus with thalamic and posterior extensions. Partial removal of such cases gave poor results. Where the mass proves soft, radical excision may be possible, but not otherwise. Limited biopsy for histological study, followed by a shunt procedure and x-ray therapy seems still the only recourse.


Stiff man syndrome in a black girl.

A patient suffering from severe and continuous muscular spasms is presented. The condition has been classified as the stiff man syndrome and is the first case recorded of the condition in a young African girl. The electrophysiological, biochemical, histochemical, and ultramicroscopic aspects of this disorder have been studied. The spasm appears to be related to overproduction of brain noradrenaline.


Spinal internuncial neurones in progressive encephalomyelitis with rigidity.

The clinical and pathological features of a fourth patient with progressive encephalomyelitis with rigidity are reported and compared with those previously described. It is suggested that the muscular rigidity, abnormal postures, painful muscular spasms, and myoclonus are a product of excessive and abnormal discharges of alpha motor neurones caused by their release from control by spinal internuncial neurones. A count of neuronal perikarya in the ventral horns confirmed that the disease selectively destroyed small and medium sized neurones, most of which were spinal internuncial neurones. Experimental, clinical, and pathological evidence concerning spinal internuncial neurones is reviewed and found to conform to this theory. The pathogenesis of opsoclonus may be similar.


Computed tomography in diagnosis and management of aneurysm of the vein of Galen.

A case of aneurysm of the vein of Galen is presented to demonstrate the value of computed tomography, not only as a diagnostic procedure, but also in the overall management of the condition.


Oligoclonal banding in the cerebrospinal fluid of patients with postencephalitic Parkinsonism.

Two recent sporadic cases of progressive Parkinsonism after encephalitis are described. Both patients had two oligoclonal protein bands in their CSF. These bands were not present in patients with idiopathic Parkinson's disease and might, therefore, be useful for diagnostic purposes, particularly when the history of encephalitis is uncertain.


Standardised method of determining vibratory perception thresholds for diagnosis and screening in neurological investigation.

Vibration threshold determinations were made by means of an electromagnetic vibrator at three sites (carpal, tibial, and tarsal), which were primarily selected for examining patients with polyneuropathy. Because of the vast variation demonstrated for both vibrator output and tissue damping, the thresholds were expressed in terms of amplitude of stimulator movement measured by means of an accelerometer, instead of applied voltage which is commonly used. Statistical analysis revealed a higher power of discimination for amplitude measurements at all three stimulus sites. Digital read-out gave the best statistical result and was also most practical. Reference values obtained from 110 healthy males, 10 to 74 years of age, were highly correlated with age for both upper and lower extremities. The variance of the vibration perception threshold was less than that of the disappearance threshold, and determination of the perception threshold alone may be sufficient in most cases.


L4/5 and L5/S1 disc protrusions: analysis of 323 cases operated on over 12 years.

A retrospective study of the results of excision of L4/5 and L5/S1 intervertebral discs in 323 patients operated on between January 1965 and January 1977 was undertaken. In every case the amount of disc excised was weighed immediately after operation. The patients had been followed up at the hospital for periods of between one and 14 years. As assessment was made of the clinical state of each patient at the end of follow-up. There was no evidence that the weight of disc excised affected the prognosis with respect either to the clinical state of the patient at the end of follow-up, or to the probability of recurrence of disc protrusion.


Congenital arteriovenous fistula producing carpal tunnel syndrome.

A case of carpal tunnel syndrome resulting from congenital arteriovenous fistula is described.


Effects of potassium depletion and insulin on resting and stimulated skeletal rat muscle.

The electrophysiological and metabolic responses to insulin of skeletal muscles from control and potassium-depleted rats were compared. Membrane potentials, action potentials, contraction parameters as well as oxygen uptake were measured in diaphragm strips or intact extremity muscles from the two groups, and similar measurements were made in vivo. The muscles were examined in solutions with normal potassium concentration [K]o , reduced [K]o, and in normal [K]o and in normal [K]o with ouabain, in each case before and after insulin, 400 mU/ml. In normal solution, the depleted muscle contractions were weaker and slower than control. The depleted muscles, already having low potassium conductance, are paralysed by the further reduction of potassium conductance after insulin. Hyperpolarising effects of insulin-induced Na/K pumping are offset in the depleted muscles with a high sodium conductance and low [K]o. Respiration is about normal at rest in depleted muscles, despite increased [Na]i, suggesting that the sodium is sequestered. After insulin, reduction of [K]o, or ouabain plus insulin, the depleted fibres take up more O2 than controls. In the presence of ouabain, this respiratory stimulation is believed to represent response to Ca++ influx. The K-depleted rat does not seem to be an entirely satisfactory model of the human disease hypokalaemic periodic paralysis.


Muscle fibre excitability and resting membrane potential in hamster muscular dystrophy.

Measurements of resting potential carried out in vivo in the dystrophic hamster and also measurements of muscle excitability showed no difference between dystrophy and healthy animals.


Relationship between plasma propranolol concentration and relief of essential tremor.

The relationship between plasma propranolol concentration and relief of essential tremor was examined in 11 patients during treatment with oral racemic propranolol in doses of 30 to 640 mg/day. Although propranolol decreased tremor in all 11 patients, the degree of improvement varied widely in individuals (mean 51%, range 25--90%), and was not related directly occurred at plasma propranolol concentrations below 20 ng/ml (0.077 mumol/l) and, in three others, below 40 ng/ml (0.154 mumol/l). It is concluded that the optimum response of essential tremor to propranolol is achieved at relatively low plasma propranolol levels, levels which are obtained by daily propranolol doses of 120--240 mg.


Fibrin degradation products in the cerebrospinal fluid of patients with pneumococcal meningitis.

Raised levels of fibrin degradation products were found in the cerebrospinal fluid of nearly all of 35 patients with pneumococcal meningitis. The mean level was higher in patients who died subsequently than in those who survived. Cerebrospinal fluid from patients with pneumococcal meningitis showed increased fibrinolytic activity as assessed by clot lysis, suggesting local production of fibrin degradation products within the subarachnoid space.


Multiple sclerosis presenting with acute remitting psychiatric symptoms.

Two patients are described in whom acute symptoms of apparently primary psychiatric disease could be diagnosed in retrospect as due to multiple sclerosis. In both patients the initial symptoms recovered completely. In a third patient, also presenting with mental symptoms, this diagnosis would not have been suspected on clinical grounds but is suggested by the results of modern diagnostic techniques.


Auditory cortex lesions and interaural intensity and phase-angle discrimination in cats.

1. A currently unresolved question concerning the effects of auditory decortication on sound localization is whether or not operated animals have a normal capacity for discriminating the small interaural differences in phase angle or intensity that result from the spatial separation of sound sources relative to the head. The present experiment was designed to provide data relevant to this question. 2. Four normal and three operated cats (bilateral ablations of AI, AII Ep, SII, I-T), wearing stereo headsets, were tested with an active avoidance procedure to detect reversals in the interaural phase-angle or intensity relations of binaural 1-kHz tones. For both groups of cats, the detection thresholds for interaural intensity and phase angle were found to be close to 1 dB and 5 degrees, respectively. 3. In addition, we found that both unoperated and operated cats exhibited positive transfer from the original lateralization task involving the detection of interaural reversals of phase angle or intensity to a new test, which required the cats to identify, in an absolute sense, which ear received the leading or louder signals. 4. Thus, the present investigation provides additional evidence that the neocortex has no primary sensory role in sound localization.


Neuronal correlates of siphon withdrawal in freely behaving Aplysia.

1. Central neuronal mechanisms of siphon withdrawal in Aplysia were studied for the first time in intact, freely behaving animals by means of population recordings from implanted whole-nerve cuff electrodes. Intracellular follow-up studies were then conducted when the same animal was reduced to a semi-intact preparation. 2. Background spontaneous activity in the siphon nerve consisted of low-frequency firing of a population of efferent units containing identified siphon motoneurons. 3. Spontaneous patterned bursts of efferent activity occurred irregularly and were associated with all-or-nothing contractions of the parapodia, gill, and siphon. Spontaneous bursts were due to centrally generated activity in the interneuron II (INT II) network, an oscillatory network with endogenous pacemaker properties. 4. In intact animals, even weak tactile stimuli to the siphon typically triggered an INTII burst shortly after the stimulus-locked efferent activity. Thus, the stimulus can phase-advance the INT II  oscillator. In semi-intact preparations, short-latency INT II bursts were triggered less less frequently and required more intense stimuli. 5. With weak to moderate-intensity stimuli in intact animals, the presence of short-latency triggered INT II bursts largely determined the duration of the siphon component and amplitude of the gill component of the withdrawal reflex. 6. When stimuli were repeated over a range of interstimulus intervals (from 60 to 1 min), the likelihood of triggering a short-latency INT II burst die not change systematically. Thus, the ability of the siphon stimulus to stably entrain the all-or-none INT II component over a wide range of intervals will interact behaviorally with the decrement of the monosynaptic component of the reflex with repetition.


Potentials evoked by alvear tract in hippocampal CA1 region of rats. I. Topographical projection, component analysis, and correlation with unit activities.

1. The field potentials and unit activities evoked by the alvear tract (AT) in CA1 region of the dorsal hippocampus of rats were studied under sodium pentobarbital anesthesia. 2. The localized activity evoked anterior to an AT stimulus began as a compound action potential, followed by a slower negative wave, and ended in a long-lasting, slow positive wave. Observed with a 64-electrode recording array, topographical projections of the AT in CA1 were seen as parallel strips inclined at an angle of 5-30 degrees medially from the sagittal plane. 3. Three overlapping components in the averaged evoked potentials (AEPs) were distinguished. The first event (component I) was a brief compound antidromic action potential of pyramidal cells. The second field event (component II) reversed from surface negative to deep positive at 200 micrometer from the ventricular surface, increased rapidly with stimulus intensity, potentiated with double shocks, and followed stimulus frequency up to 50/s. The third component was long lasting (up to 200 ms), surface positive and ventral negative (turnover at 150 micron below the pyramidal layer), followed stimulus frequency up to about 10/s, and saturated at a low stimulus intensity (about 3 x threshold). 4. In some preparations, another fast negative peak of about 2 ms duration was found to follow the axon compound action potential on the hippocampal surface and appeared to propagate from the pyramidal layer to the ventricular surface. It was probably of nonsynaptic origin, perhaps due to the centrifugal basal dendritic spikes of the pyramidal cells. 5. Single units were recorded in CA1. Antidromic units were identified by their firing at a fixed latency (1.5 ms) and ability to follow high stimulus frequencies. Units firing at about 2.7 ms latency possessed characteristics of monosynaptic excitation. Under light anesthesia, many of the latter units also showed a late, prolonged suppression of background firing. Tentative interneuronal types fired with peak latencies of 4-5 ms or showed prolonged increase in firing rate. 6. From the correlation with unit post-stimulus time histograms, AEP component II was inferred to be the extracellular, monosynaptic, excitatory postsynaptic potentials, and component III the di- or polysynaptic inhibitory postsynaptic potentials. These postsynaptic potentials were generated by the pyramidal cells and interneurons.


Representation of sound frequency and laterality by units in central nucleus of cat inferior colliculus.

1. The discharges of 632 units were isolated extracellularly during 42 penetrations of the central nucleus of the inferior colliculus (ICC) in 21 adult cats lightly anesthetized with pentobarbital and ketamine. Microelectrode penetrations were directed from caudal to rostral through ICC, parallel to the Horsley-Clarke (H-C) horizontal and sagittal planes. 2. The threshold best frequency (BF) and binaural response properties were examined for each unit, with the aim of elucidating the organization of these discharge characteristics within ICC. 3. Binaural unit classes consisted of monaural (contralateral) (EO), binaurally phase-sensitive (delay), contralateral excitatory/ipsilateral inhibitory (EI), binaurally excitatory (EE), and other more heterogeneous interaction patterns (other). 4. Detailed histological reconstruction of electrode tracks allowed the recording site for each unit to be related to the three dimensions of ICC. This structure was divided into three lateromedial and three rostrocaudal blocks such that each block contained a similar number of units, enabling meaningful statistical comparisons. Low (3.2 kHz greater than BF) and high (3.2 kHz less than BF) best-frequency classes provided a correlate of dorsoventral location. 5. The arrangements of BFs within ICC were found to be compatible with a model of this structure in which units having similar BFs are organized into layers lying in the H-C horizontal plane medially and gradually tilting in both a ventrolateral and ventrorostral direction. Low frequencies are concentrated dorsally and laterally; high frequencies, ventrally and medially. A rostrocaudal BF difference arises only in lateral aspects of the ICC, where lower frequencies are encountered rostrally. 6. Binaural response classes were distributed differentially throughout ICC. Thus, EO units were concentrated caudally, ventrally, and laterally, while delay units were in greatest numbers rostrally, dorsally, and laterally--almost totally segregated from EO and EI units. The latter populations overlapped ventrally and laterally, but EI units were in greatest density rostrally. The EE class occurred throughout the nucleus, but was most common medially. 7. It is suggested that the differential distributions of binaural responses reflect a partial segregation of the afferents, arising in the superior olive and cochlear nucleus, which terminate in ICC. The central nucleus of the inferior colliculus thus may be composed of several functionally segregated subregions contained within a common tonotopic organization.


A comparison of visual-response properties in cat's parabigeminal nucleus and superior colliculus.

1. The visual-response properties of single cells in the cat's superior colliculus and parabigeminal nucleus were compared. In the colliculus, 151 cells (restricted to the upper layer) were studied, and in the parabigeminal nucleus, 134 cells. 2. Response characteristics in the two structures were similar in many respects: among these were receptive-field size, ocular dominance, and lack of specificity for stimulus shape and contrast (light versus dark). 3. Quantitatively, there were some significant differences between the two populations of cells. Parabigeminal neurons tended to respond more brisky and reliably, while being less selective for those stimulus parameters tested (size, velocity, and direction of movement). Spontaneous activity was much higher in the parabigeminal nucleus than in the colliculus. Finally, parabigeminal cell responses to stationary stimuli were somewhat brisker than those of tectal cells. 4. These data suggest that a physiologically distinct population of tectal cells sends input to the parabigeminal nucleus, probably with some convergence on individual cells.


Connections and visual-field mapping in cat's tectoparabigeminal circuit.

1. The aim of these experiments was to analyze the organization of the reciprocal connections between the cat's superior colliculus and parabigeminal nucleus. Both physiological and anatomical techniques were employed. 2. A population of cells in the superficial gray and upper optic layers of the colliculus was labeled retrogradely by horseradish peroxidase injections into the parabigeminal nucleus. No other sources of input to the nucleus were found in the brain stem or diencephalon. 3. A map of the visual field within the parabigeminal nucleus was reconstructed by plotting visual receptive fields at 350 parabigeminal sites with microelectrodes. The map resembled that found in the colliculus, although it was considerably less orderly. The entire contralateral visual field was represented and, in addition, roughly the central 40 degrees of the ipsilateral hemifield was included; futhermore, the expansion of the central visual field was similar to that of the tectal map. 4. The return parabigeminal projections to the caudal parts of the two colliculi, representing the contralateral hemifields, were in register with the tectal visual-field maps. In contrast, the parabigeminal pathways to the anterior segments of the two colliculi, representing part of the ipsilateral visual fields, were not clearly topographic. The projection to this part of the contralateral colliculus showed little order, while that to the ipsilateral colliculus was extremely sparse. 5. A single site in the colliculus can be the target of axons from nonhomologous locations in the two parabigeminal nuclei; so that both parabigeminal inputs are in register with the tectal map.


Effects of temperature and deuterium oxide on crustacean stretch receptor.

1. The receptor potential was recorded intracellularly from the isolated stretch receptor neuron of crayfish. Total substitution of D2O for H2O in the bathing solution reversibly decreased the amplitude of the receptor potential to a level of 34% of the control. The input resistance of the neuron was slightly increased by the D2O treatment, while the resting potential and the input capacity were virtually unchanged. The viscoelastic property of the receptor muscle was not altered by the D2O substitution. Thus, D2O seems to inhibit directly the activation process of the receptor potential. 2. Temperature change over the range of 25-5 degrees C did not affect the amplitude of receptor potential. However, the input resistance of the neuron was increased about twofold by the lowering of temperature from 25 to 5 degrees C. 3. We conclude that when the temperature is lowered, the receptor current is diminished, but this decline is just about compensated for by the increase in membrane resistance, resulting in a near constancy of the receptor potential. This is the cellular basis for the relative constancy of the transduction process of the stretch receptor in the face of large temperature changes. On the other hand, in the case of D2O substitution the compensation mechanism of the resistance increase does not work, and the sensory transduction is inhibited substantially.


Degree of interocular synchrony required for maintenance of binocularity in kitten's visual cortex.

1. The importance of synchronous activation in maintaining cortical binocularity was studied physiologically in kittens that had been reared under different regimens of alternating monocular deprivation. 2. Three different techniques were employed to provide alternate monocular stimulation: a) mechanical shutters placed before the animals' eyes; b) goggles fitted with complementary colored cutoff filters, which restricted visual input to one eye at a time; and c) two rotating gratings that were 90 degrees out of phase. In the third technique, the gratings were always orthogonal to one another and viewed separately through cutoff filters. This allowed us to exploit the orientation selectivity of cortical cells and thereby stimulate them alternately through each eye without simultaneously affecting activity in the dorsal lateral geniculate nucleus (dLGN). 3. We based our conclusions on a sample of 691 neurons, which we recorded in 21 animals. Results with all techniques were remarkably consistent. Binocular cortical inputs predominated at normal or nearly normal levels, even when a number of seconds elapsed between successive exposures of each eye. 4. An interonset interval of at least 10 s was required to make a substantial reduction in binocularity. This interval can be separated into two parts--the duration of exclusive monocular stimulation and the time when neither channel receives input. Of these, the latter appeared to be less important. Blanking times of 0.15--1.0 s did not affect binocularity if the interonset interval was 1 or 10 s; and in one experiment where the blanking time was 9 s, the resulting disruption in binocularity was less than that found with shorter blanking times and the same interonset interval. 5. Our results imply that mechanisms responsible for the disappearance of binocular cortical inputs require independent stimulation of each eye for periods of at least a few seconds; this stimulation must be of a kind that is known to excite cortical cells. Our results with the rotating grafting show, in addition, that the mechanisms whose timing we have measured are intrinsic to the cortex.


Responses of vibrissa-sensitive cortical neurons in normal and prenatally X-irradiated rat.

1. Rats were irradiated by 200 R of X ray on day 17 (the 18th day) of gestation through the body wall of the mother. When they underwent the following electrophysiological tests at the age of 3-4 mo, the somatosensory cortex showed a lack of layers II, III, IV, and Va, as described by previous investigators (3, 4). 2. Spike responses to quick whisker deflections were recorded from single cells in the somatosenory cortex of normal and prenatally X-irradiated rats. 3. In normal animals, single units often responded to several whiskers, but the magnitudes (response latency and firing probability) of the responses were graded around a whisker in the "center" of the field that gave rise to the strongest response. During electrode penetration perpendicular to the cortical surface, such a center remained unchanged or shifted to another whisker that was immediately adjacent. As for the large-sized, initially positive unitary spikes (typically 2 mV or higher) sampled in this study, no systematic change in the response latency, the size of receptive field, or response probability was detected during the penetration. 4. The above description holds also for the irradiated rats except that the response latency was prolonged when compared to the normal controls. 5. Cortical laminar analysis of field potentials revealed that while the earliest electric sink appeared in layer IV in the controls, that in the irradiated rats was observed in layer Vb. However, there was no difference in the latency of these potentials between the two groups, suggesting that vibrissal sensory signals reach the cortical level normally even in the irradiated rats. The prolonged latency of the irradiated cortical neuronal response could thus be ascribed to an abnormal intracortical delay, which was most likely associated with the failure of development of layer IV stellate cells in these preparations. 6. A possibility as to how the layer IV stellate cells are involved in input-output relationships in the normal somatosensory cortex is presented and discussed.


Malignant pineal region tumors. A clinico-pathological study.

Eight patients with primary malignant pineal tumors have been seen at this institution over the past 6 years; six of them underwent definitive surgical exploration. Complete gross microsurgical excision of well encapsulated tumors was possible in four of these patients. In two cases of pineal germinomas, a biopsy and a subtotal resection were carried out because of the known radiosensitivity of this tumor. These six surgical patients all received postoperative craniospinal radiation and continue to do well up to 6 years postoperatively. Two nonoperative patients were initially treated at other institutions by ventriculoperitoneal shunt and radiation and were the only ones to develop metastatic disease. One patient had metastasis of her pineoblastoma to her unirradiated spinal canal and the other patient had metastasis of his germinoma to the peritoneum. The former patient was quadriplegic on admission, although her pineal tumor was no longer visible on computerized tomography (CT), and she died of pneumonia. The latter patient's tumor secreted the beta chain of human chorionic gonadotropin (HCG). This patient's massive metastatic tumor burden completely regressed as determined by body CT scan and HCG levels after four courses of chemotherapy with bleomycin, vinblastine, and cis-platinum. In 20 patients with lesions of the pineal region, craniotomy was associated with only one death (a patient with metastatic adenocarcinoma). Thus, microsurgery for pineal tumors provides either a reasonably safe potential for complete tumor extirpation and possible cure, or a tissue diagnosis which is necessary for appropriate therapeutic planning for radiotherapy and/or chemotherapy. The traditional therapeutic approach of empiric radiotherapy without a tissue diagnosis for pineal lesions may no longer be warranted.


Results of microsurgical management of intracranial aneurysms.

This paper presents the results of a total of 468 aneurysm operations performed on a consecutive series of 463 patients in an 8-year period, using microsurgical techniques. About two-thirds of the patients were operated on within the first 2 weeks after hemorrhage. The postoperative mortality was 4.5%. A good result was obtained in 74.5% of cases, and a fair result in 11.8%, whereas 9.2% were permanently disabled. Hypothermia was used in 142 operations, and 326 were carried out under induced hypotension. Immediate and late results of surgery are discussed with reference to selection of patients, timing of surgery, and the anesthetic and operative procedures.


Microneurosurgery for aneurysms of the basilar artery.

The authors report microsurgical treatment in 32 cases of basilar artery aneurysms, operated on with good results in 28 cases, fair results in one, and poor results in one; there were two deaths. Twenty-nine patients (91%) were able to return to social activities. Characteristics of the surgical techniques include 1) taking a transsylvian route; 2) retracting the M1 portion of the middle cerebral artery (occasionally the C1 portion of the internal carotid) medially with tapered brain retractors; and 3) approaching the aneurysm through and between perforators arising from the posterior cerebral artery in cases of high-placed basilar bifurcation. With regard to instrument improvements, tapered brain retractors, a multipurpose head frame, and bayonet clips (Sugita design) proved very helpful.


Microvascular embolization of cerebral arteriovenous malformations: A technical variation.

A useful variation of an established technique is described for embolization of cerebral arteriovenous malformations. Silastic sponge emboli that fit into No. 16, 17, and 18 stub adapters are passed through standard-sized transfemoral catheters. Of 28 treated patients, obliteration was regarded as very successful in 16. Partial success was achieved in four. Eight were regarded as failures because the reticulum was too large for these microemboli.


Subclavian steal syndrome. Part 1: Proximal vertebral to common carotid artery transposition in three patients, and historical review.

Three patients with central nervous system symptoms due to subclavian steal syndrome were treated with proximal vertebral to common carotid artery transposition. Neurological symptoms were relieved or improved in all three, with no decrease in blood pressure or pulse in the ipsilateral upper extremity. The colorful history of this syndrome is reviewed, and the various surgical approaches to its treatment are discussed. Although the literature suggests that the commonly used carotid to subclavian artery bypass graft and other similar extrathoracic procedures are generally safe and effective for relief of symptoms of the steal, there is also evidence that these bypasses may fail to restore antegrade flow in the vertebral artery, and, in fact, may steal from the carotid artery. Thus, the blood flow provided to the brain by these procedure may be hardly more than that provided by vertebral artery ligation, whereas the principal effect is to restore blood flow into the upper extremity. Vertebral artery ligation alone has been used in 20 patients, with neurological improvement in all cases and production of persistent intermittent brachial claudication in only one. These considerations and our patient experience suggest that a relatively simple operation, proximal vertebral to common carotid artery transposition, which emphasizes restoration of flow to the brain rather than to the upper extremity, may be preferable for most patients with neurological symptoms of subclavian steal syndrome.


Subclavian steal syndrome. Part 2: Intraoperative vertebral artery blood flow measurement.

Intraoperative vertebral artery blood flow was measured in two patients with symptomatic subclavian steal syndrome, before and after proximal end-to-side vertebral to common carotid artery transposition. This confirmed retrograde flow in the vertebral artery before transposition, and antegrade flow after transposition. The measured flow rates were compared to values in other series involving different operative procedures for correction of symptomatic subclavian steal. The greatest mean antegrade flow rates in the vertebral artery were restored by proximal end-to-side vertebral to common carotid artery transposition.


Acute cerebral revascularization after regional cerebral ischemia in the dog. Part 2: Clinicopathological correlation.

The efficacy of cerebral revascularization by anastomosis of the superficial temporal artery (STA) to the middle cerebral artery (MCA), performed 4 and 24 hours after a regional MCA infarction had been produced by combined occlusion of the MCA and internal carotid artery, was tested in 12 dogs. To control possible intercurrent variables, seven other dogs remained untreated and five had a sham operation. Clinical and pathological changes were recorded and analyzed. An incidence of 85% infarction was obtained in the untreated control group. The severity of the clinical deficits and pathological changes for the anastomosed groups were greater than those seen in the untreated control group. The extent of the infarction was significantly greater (p less than 0.05) in the anastomosed groups than in the sham-operated and control groups. Hemorrhagic infarcts occurred in most of the dogs in the anastomosed groups, but were not present in either control group (p less than 0.05). Two dogs in the 4-hour and one in the 24-hour group improved more than any control dog, but the difference was not statistically significant (p greater than 0.05). In two dogs with occluded anastomosis the clinical deficits and the pathological changes were less than those seen in animals with patent anastomosis. The severity of the pathological and clinical changes correlated well with the reestablishment of flow in the MCA territory. It is proposed that cerebral revascularization at 4 and 24 hours following a regional MCA infarct in the dog is followed by an exacerbation of the microcirculatory obstruction, cerebral edema, and infarction. From improvement noted in three animals the authors suggest that under special conditions the revascularization could benefit some cases following acute cerebral infarction.


Endothelial lesions after temporary clipping. A comparative study.

The effect of temporary clipping on the arterial endothelium of rats was examined with scanning electron microscopy. The opening pressure of four Heifetz clips was modified by changing the springs. Four different clip forces (20, 35, 45, and 65 gm), four periods of clipping (10, 30, 60, and 180 minutes), and three vessel diameters (smaller than 1 mm, 1.1 to 1.3 mm, and 1.4 to 2 mm) were compared. Different grades of endothelial damage were observed. On gross examination the damage involved a detachment of endothelium and the adherence of platelets to the subendothelial tissue. The duration of clipping seemed to be of more importance than the clip force, whereas the vessel diameter had no recognizable influence.


Minimum vascular occlusive force.

A mathematical analysis of the minimum occlusion force necessary to occlude small vessels based on the parametric influence of blood pressure, vessel diameter, clamp width, and vessel shape after clamping was performed. The results were confirmed by in vivo experimentation with 60 rat aortas (of 1.8 to 2.4 mm caliber) using a variable-force clamp gauge developed in our laboratory. Experimental and theoretical results differed by only 3 gm. Scanning electron microscopy revealed that the initial changes in the endothelium occurred in smaller radii of curvature. Increased pressure resulted in gross morphological changes across the vessel. The minimum occlusion force (as determined by the variable-force clamp gauge) produced only minimal endothelial damage.


Acute intracranial hypertension and auditory brain-stem responses. Part 1: Changes in the aduitory brain-stem and somatosensory evoked responses in intracranial hypertension in cats.

Changes in auditory brain-stem responses (BER's) and somatosensory evoked responses (SER's) were investigated to correlate mass volume, intracranial pressure, and neurological dysfunction in mass-induced intracranial hypertension in cats. As the intracranial pressure was raised by expansion of a supratentorial balloon, the late components of the SER's were suppressed first, followed by the early components of the SER's, then Wave V and Wave IV of the BER's, in that order. This suggests that the nonspecific reticular projections are most vulnerable to compression ischemia, and the specific somatosensory pathways are the next most vulnerable. Neural activity of the auditory pathways in the upper brain stem was also gradually suppressed, but less so than that of the somatosensory pathways. After complete transtentorial herniation, in spite of immediate mass evacuation, the function of the somatosensory pathways was greatly impaired, often irreversibly. The neural activity of the auditory pathways in the upper brain stem revealed progressive recovery during a 3-hour period. The measurements of BER Wave V is thought to be useful in predicting transtentorial herniation.


Anterior fibular strut graft in neoplastic disease of the cervical spine.

An anterior operative procedure using a strut of fibular graft material was performed either alone or in combination with a posterior stabilization in five patients with cervical spine instability secondary to neoplastic disease. Osseous tumor was present in four of the five patients (osteoblastoma, metastatic adrenal carcinoma, metastatic renal cell carcinoma, multiple myeloma) and the fifth had spine instability as a result of a posterior decompression for cervical spinal cord glioma. The anterior approach using fibula to replace diseased vertebrae and provide axial support for the neck was a valuable therapeutic modality in this group of patients, all of whom had a limited life expectancy. Cervical spine stability obtained by operative intervention led to a reduction of neck pain and maintenance of ambulation until the neoplastic condition became terminal.


Subtotal neonatal calvariectomy. A radiographic and histological evaluation of calvarial and sutural redevelopment in rabbits.

A subtotal calvariectomy was performed on rabbits between 10 and14 days of age. The animals were allowed to grow and were then sacrificed serially so that the sutural and skeletal redevelopment could be analyzed through a combination of gross, radiographic, and histological techniques. The results indicate that calvarial regeneration is a progressive process with a definite pattern and rate of development. During the regenerative process, bone was deposited both at the surgical margin and as islands within the srugical defect. The eventual approximation of these areas of ossification produced multiple fibrous articulations. The majority of these articulations were obliterated by bone union, except for the midsagittal, coronal, and metopic sutures, which were re-established in their appropriate antomical positions. The maintenance of dural integrity during the surgical phase and the regeneration and establishment of pericranial continuity during the postoperative period were believed to be important in the re-establishment of normal sutural and skeletal architecture.


Carotid-cavernous fistula following percutaneous retrogasserian procedures. Report of two cases.

Carotid arterial puncture during percutaneous retrogasserian procedures is a common but usually harmless complication. Strokes, resulting presumably from carotid artery thrombosis, have been reported previously following percutaneous retrogasserian coagulation. The authors report two cases of carotid-cavernous fistula, one following percutaneous radiofrequency rhizotomy and the other after percutaneous retrogasserian block. The latter patient had an anomaully by intracavernous injection of isobutyl-2 cyanoacrylate, using intra-arterial balloon flotation catheters. Carotid-cavernous fistula is a potentially serious complication of such procedures, and may be more common than realized since small fistulas may close spontaneously.


False aneurysm of the cavernous carotid artery and progressive external ophthalmoplegia after transsphenoidal hypophysectomy. Case report.

A case is reported in which a large false aneurysm and small associated fistula formed in the cavernous carotid artery as the result of laceration at the time of transsphenoidal surgery. The clinical syndrome associated with the enlarging mass and the surgical management of the lesion itself are described. The value of the midline approach to the sella is stressed, along with anatomical variants of the carotid artery.


Treatment of intraoperative middle cerebral artery occlusion with pentobarbital and extracranial-intracranial bypass. Case report.

A patient with a meningioma of the medial sphenoid wing underwent inadvertent intraoperative occlusion of the middle cerebral artery. Neurological deficit and infarction were presumably prevented by immediate administration of pentobarbital followed by extracranial-intracranial bypass.


Spontaneous regression of posterior fossa dural arteriovenous malformation.

The authors report a case of infratentorial arteriovenous malformation that regressed spontaneously within 25 months without bleeding episodes or surgical intervention. The patient's clinical symptoms, left-sided tinnitus, cranial bruit, and right homonymous hemianopsia, disappeared completely over the same period.


Posterior fossa xanthogranuloma. Case report.

A large subdural xanthogranuloma was removed from the posterior fossa of a 53-year-old woman with symptoms of Hand-Schüller-Christian disease. Two additional masses with similar density on computerized tomography were found in the hypothalamus and in the choroid plexus of the right lateral ventricle.


Surgical approach to giant intracranial aneurysms. Operative experience with 80 cases.

The authors report experience with the surgical management of 80 giant intracranial aneurysms (greater than 2.5 cm in diameter) during a 10-year period in which they performed 594 operations for aneurysms. The overall incidence of giant aneurysms was 13% but varied according to location: 20% of aneurysms of the internal carotid artery (ICA); 13% of middle cerebral artery (MCA) aneurysms; 1% of anterior cerebral artery (ACA) aneurysms; 15% of aneurysms of the basilar artery caput (BAC); and 18% of vertebrobasilar trunk (VB) aneurysms. Twenty-five patients had a subarachnoid hemorrhage (SAH), 49 had mass effect from the aneurysm, and six had ischemic events. There was no apparent difference in results related to the presence or absence of an SAH. Poor results were attributable to the operation except in the two cases of ACA aneurysm in which preexisting dementia persisted. Mortality was 4% and morbidity was 14%, varying from a combined low morbidity-mortality of 8% for ICA lesions to a high to 50% for BAC aneurysms. During the period of the study, different techniques were developed in an attempt to lower the risks of surgery. Ultimately ICA aneurysms were monitored with cerebral blood flow measurements and electroencephalography before and after temporary ICA ligation, then approached following resection of the anterior clinoid or treated with bypass in combination with ICA ligation. Aneurysms of the MCA were either opened during temporary MCA occlusion or resected in combination with a bypass procedure. Bypass grafts and circulatory arrest with extracorporeal circulation may have a role in giant aneurysms of the posterior circulation.


Direct surgical treatment of giant intracranial aneurysms.

The author has operated on 40 patients with giant intracranial aneurysms, using various surgical approaches. Giant aneurysms predominated in females (3:1) and were most common in the age group 30 to 60 years. Patients presented with subarachnoid hemorrhage (17), visual disturbance (18), chronic headache (14), transient or progressive hemispheric deficit (6), seizure (2), dementia (2), and cerebrospinal fluid rhinorrhea (1). Giant aneurysms were located at the carotid artery (25), the basovertebral artery (8), the anterior communicating artery (5), and the middle cerebral artery (2). Eight of 40 patients had one or more other aneurysms and/or associated arteriovenous malformations. Aneurysms were treated with intramural thrombosis (21), neck occlusion (7), trapping (10), proximal parent artery ligation (1), and aneurysmorrhaphy (1). After as much as 8 years of follow-up, 32 patients (80%) showed complete or marked improvement in signs and symptoms; two patients (5%) had a poor recovery. There were six surgical mortalities (15%). Giant aneurysms can be treated with respectable results if the surgeon selects the technique best suited to the particular aneurysm. In general, neck occlusion, trapping, and aneurysmorrhaphy are best for giant aneurysms of the anterior circulation, and intramural thrombosis is best for those of the posterior circulation. Extra- and intracranial vascular anastomotic techniques are also of value. For success, a flexible approach is essential.


Hyperemic and ischemic problems of surgical treatment of arteriovenous malformations.

Three patients with arteriovenous malformations are described who showed signs of massive hyperemia in the vascular territory of the normal brain proximal to arterial ligation. One additional patient had evidence of ischemia of the brain in the territory distal to ligation (steal), and in another both mechanisms were considered as operative hazards.


Computerized tomography findings in arteriovenous malformations of the brain.

Computerized tomography (CT) scans of 54 patients with an arteriovenous malformation (AVM) of the brain were reviewed. The 31 males and 23 females (mean age: 33 years) were classified according to clinical presentation: 1) intracranial hemorrhage (30 patients); 2) seizure disorder (19 patients); and 3) other neurological disturbance (five patients). A brain hematoma was identified in all of the patients in the hemorrhage group have a CT scan within 1 week of the bleed. Extension of hemorrhage into the ventricular system as seen in eight cases was invariably accompanied by severe neurological dysfunction. A high-density lesion without associated mass effect was found in 48% of patients presenting with a seizure disorder. Dilatation of the ipsilateral lateral ventricle, a common finding in this group of patients, was thought to indicate an atrophic process. Evidence of discrete brain infarction was unusual. Intravenous infusion with Hypaque provided additional information in 31 of the 35 patients so studied. Demonstration of prominent or enlarged feeding arteries and/or draining veins occurred in 20% of patients with large malformations. Six cases of angiographically occult AVM's were found. A correlation of the CT scan with clinical, angiographic, and histological findings is presented.


Possible role of the erythrocyte in causing prolonged cerebral vasospasm.

Contractile activity of the various fractions of fresh and incubated blood was studied in vitro using the isolated canine basilar artery. Of the various fractions of fresh blood, significant contraction was induced by serum, but moderate contraction was induced by platelet-rich plasma and lysed red cells, while intact red cells and platelet-poor plasma had no significant activity. The contractions induced by serum and platelet-rich plasma were blocked by phenoxybenzamine, while those induced by lysed red cells were not. Whereas serum and platelet-rich plasma lost their contractile activity after 24 hours of incubation, lysed red cells retained activity up to 7 days after incubation. Biochemical analysis of the hemolysate by means of Sephadex column chromatography revealed that the contractile substance(s) possessed a molecular weight above 5000. These results suggest the possibility that the above substance(s) may play a role in prolonged cerebral vasospasm.


Dynamics of cerebral edema. The role of an intact vascular bed in the production and propagation of vasogenic brain edema.

Brain edema was produced in cats by a standardized cortical freezing lesion. With a careful microsurgical tehnique, the injured cortex was removed as a single piece, either immediately after induction or at 2, 4, or 8 hours after lesion production. The injured brain was either discarded or replaced in its bed. Brain edema and the defect in the blood-brain barrier were assessed by determining percent dry weight, increase in volume of white matter, and spread of Evans' blue by planimetry. The results indicate that 1) if the lesion is removed immediately after production, formation of the expected vasogenic brain edema is completely abolished; 2) replacement of the frozen brain is unable to induce significant increase in permeability of the surrounding blood-brain barrier or a significant amount of brain edema; and 3) if the lesion is removed at 2, 4, or 8 hours with or without replacement, advancement of the edema front and increase in the amount of edema is stopped. It appears that an intact vascular bed is necessary for the extracellular fluid component of brain edema, and that no edemagenic factors exist within the injured brain in this model that influence either the production or propagation of the increased extracellular fluid volume.


Early neurosurgical repair in craniofacial dysmorphism.

The authors describe the operative repair and results in 16 cases of craniofacial dysmorphism. The craniofacial dysmorphic states are presumably caused by premature closure of basal skull sutures in combination with the coronal sutures. Hydrocephalus is commonly associated with these conditions and contributes to the bizarre appearance as well as the abnormal mentation that some of these patients display. Early neurosurgical intervention using the procedure of lateral supraorbital ridge advancement yields excellent results in the majority of these infants.


Long-term analysis of cerebrospinal fluid shunt infections. A 25-year experience.

The authors have retrospectively analyzed 840 cerebrospinal fluid shunting procedures over a 25-year period to determine the relationships between infection rates and several possible influences on infection. Two-thirds of all shunt infections occurred within 1 month of surgery. The very young and very old had higher infection rates. Infections became less prevalent over the period of the study, and mortality from infection decreased from 35% to 6%. Successive shunts (revisions) were found to have progressively higher infection rates. Ventriculoatrial and ventriculoperitoneal silicone plastic shunts had similar infection rates (11.4% and 12.0%). The uncontrolled use of prophylactic antibiotics had no effect on shunt infections. Staphylococcus epidermidis became gradually more prevalent over the period of the study, and eventually caused one-half of all infections. Where infection occurred in the presence of prophylaxis, the infectious organism was usually sensitive to the antibiotic being used. The surgeon was found to be the largest single factor in the incidence of shunt infections. A 25-fold variance in infection rates among surgeons could be related to individual experience and technique.


Acute intracranial hypertension and auditory brain-stem responses. Part 2: The effects of brain-stem movement on the auditory brain-stem responses due to transtentorial herniation.

Movement of the upper brain stem (inferior colliculus) was correlated with the alterations in the amplitude of wave V of the auditory brain-stem responses (BER's) during supratentorial brain compression in cats. In vivo observation of the brain stem and postmortem inspection show that suppression of the amplitude of BER wave V reflects the extent of caudal displacement of the inferior colliculus. Marked suppression of the amplitude of BER wave V (approximately 30% of control) correlates with the beginning  of transtentorial herniation, and complete suppression of the wave V indicates complete transtentorial herniation of the brain-stem and supratentorial structures. The BER wave V is thought to be a sensitive index of caudal movement of the upper brain stem due to transtentorial herniation.


Familial communicating hydrocephalus, posterior cerebellar agenesis, mega cisterna magna, and port-wine nevi. Report on five members of one family.

This report deals with a family in which the maternal grandmother, the mother, and all three male children have port-wine nevi and mega cisterna magna. Two of the three male children have, in addition, congenital communicating hydrocephalus associated with agenesis of the posterior cerebellar vermis. This case of familial communicating hydrocephalus, posterior cerebellar vermis agenesis, port-wine nevus, and mega cisterna magna represents a new neurocutaneous syndrome, possibly transmitted as an autosomal dominant.


The influence of zinc status on the levels of metallothionein in isolated perfused rat liver.

The levels of cadmium and zinc metallothionein in isolated perfused livers of zinc depleted and repleted rats were investigated. Rats (160-200 g or 90-120 g) were fed either a zinc-deficient or zinc-supplemented diet for 62 or 42 days. The 90 to 120 g rats were repleted with 30 ppm Zn2+ in the drinking water for 1, 4 and 10 days after 35 days of depletion, and another group after depletion for 21 days was repleted for 15 days on a 21% casein diet. At appropriate times livers were cannulated, removed and perfused +/- 25 mug Cd2+ as CdCl2, for 2 hours through the portal vein in a perfusion apparatus. Zinc depletion resulted in significant decreases in growth rate (1.4 versus 5.7 g/day) and liver weights. Repletion with Zn for 10 days increased the weight gain to 7.1 g/day. Depletion decreased the incorporation of Zn and Cd into metallothionein by 57 to 60%, while repletion for 1, 4 and 10 days increased the incorporation to nearly 500% of control levels. But, as repletion progressed, zinc in metallothionein fell to normal levels after 15 days. Cadmium in metallothionein did not decrease between 1 and 10 days of repletion. Zinc deficiency also reduced the zinc content of the liver by 44%, which increased to normal levels after 10 days of repletion. These data suport the conclusion that zinc status can influence the incorporation of cadmium and zinc into metallothionein.


Effect of dietary fat and vitamin E on mouse lung lipids.

To examine the effect of dietary fat on lung lipids, male weanling mice (CD-1 strain) were fed purified diets containing 5% stripped lard or corn oil and kept in chambers supplied with air filtered free of airborne bacteria. Vitamin E was fed at 0, 10.5 or 105 mg dl-alpha-tocopheryl acetate/kg diet. Dietary fat and vitamin E (0 or 10.5 mg/kg) had no significant effects on the lung levels of triacylglycerol (TG) or phospholipid (PL) molecular species through 4 weeks of intake. Alterations in lung fatty acid composition were followed through 6 weeks of intake at 0, 10.5 and 105 mg vitamin E/kg diet. Vitamin E, at all levels of supplementation, had no significant effect on mouse lung fatty acid composition. Saturated fatty acids of the lung also showed little alteration by diet, but feeding the lard diet significantly elevated oleic and palmitoleic acids. In mice fed the corn oil diet the levels of linoleic acid (18:2) were twice those of lard-fed mice, and arachidonic acid (20:4) was elevated by 15.8%. The diet elevated the mean peroxidizability index (PI) on lung tissue in corn oil-fed mice.


Effects of food or protein restriction on plasma volume expansion in pregnant rats.

The effects of either food restriction or a low protein diet on the plasma volume expansion of pregnancy was determined in Sprague-Dawley rats. Rats fed ad libitum a standard diet or fed a 25% casein diet were used as controls. Both the food restricted and protein restricted rats had a significant reduction in body weight and fetal and placental weights. The total plasma volumes were also significantly lower in the restricted groups. Plasma volume expressed per 100 g of maternal net body weight or 100 g of conceptus weight was significantly reduced only in the rats fed the 6% casein diet. Correlations between plasma volume and maternal net body weight or conceptus weight in the control groups suggested that although the conceptus can influence the degree of expansion of maternal plasma volume, maternal factors such as net body weight are more important determinants of plasma volume expansion.


Uptake of selenium-75 by human lymphocytes in vitro.

Selenite uptake by human lymphocytes was studied both in whole blood and in isolated cells. When 75Se-selenite (75Se-SeO3-2--) is supplied to whole blood, it is converted by the erythrocytes to a form which rapidly becomes bound to plasma proteins. Studies with a variety of inhibitors indicated that the process is not energy dependent but that sulfhydryl groups are required. The 75Se bound to plasma proteins is absorbed by lymphocytes in preference to 75SeO3-2-. By the use of selective inhibitors (respiratory, sulfhydryl, protein biosynthetic) it was demonstrated that the uptake of either form of 75Se requires neither energy nor protein synthesis; however, all the sulfhydryl inhibitors cause a decrease of absorption. A scheme which summarizes the pathway of selenite conversion in human blood and uptake by lymphocytes is presented; the data indicate that plasma proteins function as carriers of selenium to lymphocytes.


Studies on the severity of various amino acid imbalances in the young male rat.

Relative severities of amino acid imbalance were compared in young male rats fed diets having an amino acid imbalance with respect to various essential amino acids. In the imbalanced diets, one or more essential amino acids were made to be low, ranging from suboptimal to two times the requirement, while the other essential amino acids were present at three times the requirement. From the extent of depressions in food intake and growth, the severity of amino acid imbalance was found to be dependent upon the level as well as the type of the limiting amino acid(s) in each imbalanced diet. The overall results indicated that Met imbalance was very severe, followed in decreasing order by Ile, Trp, Leu and Val, His, Phe, Thr, Lys and Arg imbalance. The imbalance with respect to the large neutral amino acid appeared to be more severe than the imbalance with respect to the small neutral amino acid, while the imbalance with respect to the basic amino acid was least severe.


Effects of dietary calcium on blood and tissue lipids, tissue phospholipids, calcium and magnesium levels in rabbits fed diets containing beef tallow.

Levels of lipids, calcium and magnesium in blood and tissue were examined in rabbits to determine the effects of 20% beef tallow diets containing three levels of calcium, less than 0.02, 0.8 or 1.6%. In plasma, the calcium-deficient (less than 0.02%) diet contributed to elevated cholesterol and phospholipid, but had no effect on triglyceride levels. Plasma calcium decreased in the calcium-deficient group and plasma magnesium decreased in the high-calcium (1.6%) group of rabbits. Lipid levels of some tissues varied with the level of dietary calcium. Cholesterol, total phospholipid, sphingomyelin and phosphatidylethanolamine were generally elevated in livers of calcium-deficient rabbits, but the individual phospholipids were decreased in skeletal muscle. Lungs of the calcium-deficient group also had lower phospholipid levels than the high-calcium group. Liver, kidneys, brain and adipose tissue triglyceride levels were highest in the high-calcium group. The calcium level of skeletal muscle was lower in the calcium-deficient group than in the high-calcium group. Calcium in brain and adipose tissue were highest in the calcium-deficient group. Except for adipose tissue, magnesium levels of the tissues studied were not affected by dietary calcium.


Orotic aciduria and increased nitrogen catabolism in rats.

In vitro incorporation of [14C] bicarbonate into orotic acid by rat liver slices was used to study the rate of orotic acid (OA) biosynthesis in the presence of physiological (0.73 mM) and saturation concentrations (5 mM) of NH4Cl. The influence of body size on OA synthesis in rats fed purified L-amino acid diets with (C) or without (-Arg) was examined. OA biosynthesis was significantly greater at both NH4Cl concentrations examined in liver slices obtained from -Arg rats for all sizes of rats. A linear decrease (r = 0.92) in OA synthesis as a function of body size was observed for rats fed either of the diets. The rate of OA biosynthesis was also found to increase linearly (r = 0.98) in livers from rats fed increasing dietary protein when determined by incubation with physiological concentrations of NH4Cl. OA biosynthesis was also found to increase with increase in length of fasting. Alteration in urinary OA and urea confirm these rates of synthesis. These results support the hypothesis that when the urea cycle is overtaxed, carbamyl phosphate (CP) synthesized intramitochondrially by CP synthetase I may be shunted into pyrimidine biosynthesis.


Effectiveness of dietary iron and ascorbic acid in the prevention and cure of moderately long-term lead toxicity in rats.

The protective and curative effects of high levels of dietary iron and ascorbic acid on moderately long-term toxicity in rats were examined. In rats fed a diet containing 500 ppm of lead for 56 days, growth retardation, reduction of food consumption, anemia, hypertrophy of the kidney and accumulation of lead in the bone and kidney were observed, however, activities of alkaline phosphatase and GOT in the plasma did not change. Addition of 400 ppm of iron and 1% of ascorbic acid to the lead containing diet prevented the growth depression, reduction of food consumption, anemia and decreased the accumulation of lead in tissues. When these compounds were added to the lead containing diet for 18 days after feeding the lead diet alone for 38 days, almost no curative effects on lead toxicity were observed. In contrast to cadmium toxicity, dietary iron and ascorbic acid have no curative effect on established lead toxicity.


The differences of the metabolism related to vitamin B6-dependent enzymes among vitamin B6-deficient germ-free and conventional rats.

The differences of the metabolism related to vitamin B6-dependent enzymes were investigated using germ-free and conventional rats. There was a significant difference in the boyd weight gain between vitamin B6-deficient germ-free and conventional rats after about 30 days of the experiment, and the body weight gain was much less in the deficient germ-free rats than in the deficient conventional ones. Urinary excretion of xanthurenic acid was higher in the deficient germ-free rats than in the deficient conventional ones after 18 days. There was a significant difference in the activities of kynurenine aminotransferase in mitochondrial fractions of germ-free rats, but not in mitochondrial fractions of conventional ones. The activities of aspartate and alanine aminotransferases, with or without pyridoxal phosphate, significantly decreased in the deficient germ-free rats, but not in the deficient conventional ones. These findings indicate that the degree of vitamin B6 deficiency was more severe in the deficient germ-free rats than in the deficient conventional ones, and also suggest that intestinal microflora may have some effects on vitamin B6-deficient conventional rats.


Observations of the concentration of zinc and iron in tissues of vitamin B6-deficient germ-free rats.

The transition of zinc and iron metabolism in vitamin B6 deficiency was investigated using germ-free and conventional rats. In contrast to previous reports, a decrease in zinc content was not observed in the liver, pancreas, kindney, spleen, lung or testes of vitamin B6-deficient conventional and germ-free rats, but we found an increase in zinc content in the kidney of conventional rats and in the liver and spleen of germ-free rats. Vitamin B6-deficient conventional and germ-free rats retained more iron in their tissues than the control animals did, except for the spleen of germ-free rats. The deposit of iron was more evident in vitamin B6-deficient germ-free rats than in vitamin B6-deficient conventional rats, and is possibly proportional to the degree of vitamin B6 deficiency. It is possible that the deposit of iron in the organs had some influence on metabolic disorders in vitamin B6-deficient rats.


Antihypertensive action of d,l-alpha-tocopheryl nicotinate in rats.

The effects of d,l-alpha-tocopheryl nicotinate (EN) on model hypertension in rats were studied in comparison with d,l-alpha-tocopheryl acetate (EA). The progress of hypertension in young SHR during the 9th to 15th weeks after birth was markedly accelerated by replacing their driking water with 1% saline. The highly-developed hypertension in old SHR (9 months of age) was further advanced by salt-loading. Oral administration of 20 or 100 mg/kg of EN or 88 mg/kg of EA, once a day, delayed the progress of hypertension in young SHR and reduced advanced hypertension in old SHR. An antihypertensive effect of tocopheryl esters was also found in DOCA-salt hypertensive rats. The treatment with EN or EA definitely reduced the incidence of pathological changes accompanying model hypertension such as suppressed weight gain, pulmonary edema, myocardial fibrosis, cerebral hemorrhage and protected the animals from death. In antihypertensive effect, EN was about 5 times more active than EA in molecular base, and the effects of EN protecting from pathological changes associated with model hypertension were more definite than those of EA. The treatment with EN or EA reduced water and sodium retention in the DOCA-salt hypertensive animals. This fact may suggest the implication of a mechanism through electrolyte metabolism in the antihypertensive action of these tocopheryl esters.


Nutritive value of L-, DL- and D-tryptophan in the chick.

The present study was undertaken to determine the nutritive value of L-, DL- and D-tryptophan in chicks. Day-old chicks were fed commercial chick starter ration for one week and then they were given an experimental diet containing zein as a protein source for three weeks. The experimental results were analyzed by a slope ratio technique (weight gain vs. tryptophan intake). The relative biological utilization of DL- and D-tryptophan compared to L-tryptophan was approximately 55 and 15%, respectively. At the end of the experiment, the chicks were sacrificed and the concentration of free tryptophan in plasma was measured. The free tryptophan concentration in plasma corresponded closely with the increment level of tryptophan in diet when there was a normal level of dietary protein. But there was less correspondence when chicks were fed a diet low in protein.


Effect of diets supplemented with amino acids on intestinal sucrase and leucine aminopeptidase activities in rats.

In order to investigate the relationship between dietary amino acids and protein, and activities of intestinal sucrase [EC 3.2.1.26] and leucine aminopeptidase [EC 3.4.11.1, LAPase] in rats, the effect of supplementation of amino acids into a protein-free diet and a low casein diet containing sucrose as the carbohydrate source on these enzyme activities was studied. The segmental weights of the small intestine and its mucosa of rats fed the protein-free diet supplemented with L-methionine or with L-methionine and L-threonine at 0.1 or 0.2% levels were significantly higher than those of rats fed the protein-free diet or one supplemented with L-glutamic acid, but there was no difference in the segmental activities of the sucrase and LAPase among rats fed these diets. On the other hand, the supplementation of methionine or methionine plus threonine to the 5% or 10% casein diet produced remarkable increases in the segmental weights of the small intestine and its mucosa as well as in the segmental activities of the sucrase and LAPase. There was no difference between the segmental sucrase activity of rats fed the 10% casein diet supplemented with 0.2% methionine ad libitum and that of rats fed this diet under restricted feeding conditions, although the segmental LAPase activity was affected by the amount of food consumed.


Effect of the combination of voluntary exercise and dietary protein levels on the deposition of glycogen, liver and serum lipids in mice.

The effects of voluntary exercise on the growth, glycogen of muscle and lipid contents of the liver and serum of mice fed different levels of dietary protein were investigated. In both the exercise and non-exercise groups, body weight gains were significantly greater in the 20% and 30% protein diet groups than in the 6% and 4% protein diet groups. After 6 weeks of age, it was shown that the amount of voluntary exercise by the 6% and 4% protein diet groups was greater than that by the 20% and 30% protein diet groups. As for hematological status, the raising of hemoglobin levels due to increasing dietary protein levels was further exaggerated by voluntary exercise. Hematocrit values rose with the increase in dietary protein levels. However the effect of exercise on hematocrit values was not clear. Liver glycogen levels, which were elevated with the increase in dietary protein levels, rose further due to exercise, though no changes were observed in muscle glycogen due to dietary protein levels  and exercise. The lipid contents of the liver in all groups tended to be lower in exercise groups compared with non-exercise groups and it was observed that the high levels of dietary protein depressed the increase in liver lipids. Liver triglyceride levels of all groups fed the dietary protein levels except for the 20% casein diet group decreased due to voluntary exercise, and liver triglyceride levels were also lowered as dietary protein levels increased. The levels of serum triglyceride of all groups decreased due to voluntary exercise. This phenomenon was most remarkable in rats fed a 6% casein diet. The tendency for serum cholesterol levels to decrease due to exercise. However it was not further influenced by voluntary exercise in the 4% casein diet group.


Some lipogenic enzyme activities in rat livers in which an excessive fat accumulation occurred due to feeding low-level amino acid mixture diets.

In liver homogenates of rats fed a low-level diet of Wheat-Rice- or Miyazaki-pattern amino acid mixture, some enzymes such as glucose-6-phosphate dehydrogenase, ATP citrate lyase, fatty acid-synthesizing enzymes, malic enzyme and L-alpha-glycerophosphate dehydrogenase, whose activities are indicators of lipogenesis have been determined from the viewpoint of the mechanisms producing fatty liver. In the early experimental period, malic enzyme activity increased more markedly in rats fed low amino acid mixture diets than in the control group, and L-alpha-glycerophosphate dehydrogenase activity in the liver increased slightly. Conversely, ATP citrate lyase and fatty acid-synthesizing enzyme activities remained almost at control levels, or glucose-6-phosphate dehydrogenase activity tended to decrease. These results suggest that some other associated factors, such as depression of the lipid transfer system in the liver rather than accelerated lipogenesis itself, may be the main cause of the fatty livers produced under these nutritional conditions.


Purification and characterization of a trypsin inhibitor from rice bran.

A trypsin inhibitor was isolated and purified from the bran of rice, Oryza sativa, by extraction with 1% sodium chloride, heat treatment, ammonium sulfate precipitation, ion-exchange chromatography on a CM-Sephadex C-25 and gel filtration on a Sephadex G-75. The final preparation was homogeneous by electrophoretic analysis. Rice bran trypsin inhibitor (RBTI) had a molecular weight of about 14,500 and an isoelectric point of 8.07. The amino acids, acid composition was characterized by high contents of basic amino acids, aspartic acid, glutamic acid, proline and cystine. BRTI inhibited bovine trypsin at an inhibitor-enzyme molar ratio of 1:1.6. It displayed, however, nobility to inhibit alpha-chymotrypsin, pepsin, papain and subtilisin BPN'.


A method for verifying the completeness of cohorts used in occupational mortality studies.

The completeness of cohorts identified for historical prospective studies of occupational diseases is subject to many sources of error, including clerical oversight or negligence and poor company record-deeping practices. It is impossible to verify the completeness of occupational cohorts based solely on plant records, since the company files themselves may not be 100% complete. This article presents a method of verification based on IRS records which is completely independent of company-held records. The sensitivity and effectiveness of the method are demonstrated through the application of the verification scheme to an ongoing study of man-made mineral fiber workers in the United States. In six participating plants, 1990 (21.4% of the original cohort) additional records were uncovered following an initial verification and a second complete survey of plant files. It is believed that, without independent verification, errors of this magnitude may be present in many historical prospective studies of this type. An independent verification should be incorporated into all occupational study designs which utilize historical plant records as the primary data base.


Validation of a bench stepping test for cardiorespiratory fitness classification of emergency service personnel.

Field tests are used in many occupations to screen and classify personnel for cardiorespiratory fitness. Presumably these tests yield predictive results which correlate well with maximal oxygen uptake (VO2 max), the most widely-accepted criterion of cardiorespiratory fitness. The purpose of this study was to validate one of the most popular field tests, the modified Kasch Pulse Recovery Step Test (KPRST), used by several emergency service agencies in Southern California. One hundred fourteen male state traffic officers from the California Highway Patrol, ranging in age from 24 to 56 years, performed treadmill VO2 max tests to volitional fatigue and the modified KPRST. Heart rates taken during the first and last 10 seconds of the one-minute recovery period for the modified KPRST compared against treadmill VO2 max values yielded correlations of --0.25 and --0.27, respectively, indicating that the modified KPRST is a poor predictor of cardiorespiratory fitness for the population studied. These results suggest that agencies should carefully validate any predictive measure of cardiorespiratory health and performance before adopting that measure for screening purposes and cardiorespiratory classification.


Heart disease risk factors in Los Angeles County safety personnel.

Eight generally accepted heart disease risk factors (age, sex, family history, blood pressure, cholesterol, weight, smoking and exercise) were used in the computation of a cardiac index (RISKO) for 4,066 safety personnel of the County of Los Angeles. Seventy-one individuals subsequently developed coronary disease. The index had significant value in identifying the individuals who were to develop symptomatic coronary disease, and its discriminative power was comparable to the power of the Framingham index.


Bone mineral content in term and preterm appropriate-for-gestational-age infants.

Photon absorptiometry adapted for use in small infants was utilized to measure bone mineral content in 42 term and 30 perterm appropriate-for-gestational-age infants. BMC at birth correlated significantly with gestational age and birth weight. Sequential measurements of BMC in premature infants during the first three months showed that the postnatal increase in BMC was significantly less than the BMC expected in utero. We speculate that decreased intake of calcium and phosphate effects postnatal bone mineralization in premature infants.


Plasma lipids, lipoproteins, and blood pressure in female adolescents using oral contraceptives.

Comparative profiles are reported for plasma lipids and lipoproteins, blood pressure, smoking, and selected socioeconomic variables for females less than 20 years of age using oral contraceptives and for pair-matched non-users from the Lipid Research Clinics Prevalence Study. About 5% of adolescent females reported OC use; they had significantly higher levels of plasma total cholesterol, triglyceride, and high-density lipoprotein-cholesterol than did the non-users. Significantly more non-users of OC belonged to households of the lowest occupational status; no differences in OC usage by educational status of the head of household were discernible. Of the OC users, 58% were classified as current smokers, as compared with 23% of the non-OC users.


Reducing adolescent obesity through a school health program.

The feasibility and effectiveness of conducting a school-based multi-component behavioral weight reduction program was tested on 119 overweight junior high school students. Four schools in the metropolitan New York area were randomly assigned to either the experimental or control conditions. After participating in a school-wide health-profile screening, students in the experimental group were invited to participate in a ten-session weight reduction program that included behavior modification, nutrition education, and exercise management. Comparison of the experimental and control groups with respect to changes on weight and triceps skinfold measures indicated significant differences between the two groups. Although the long-term effectiveness of the weight reduction program cannot be determined, the present study clearly demonstrates the short-term effectiveness and feasibility of conducting such a program in a school setting.


Potentiation of neuromuscular weakness in infant botulism by aminoglycosides.

A retrospective study of ten patients with infant botulism who received gentamicin or kanamycin suggests that aminoglycoside antibiotics potentiate muscular weakness and precipitate respiratory failure as late as 27 days after onset of the disease. Although it is difficult to separate progression of the disease from the effects of antibiotics, the rapidity of deterioration following aminoglycoside treatment and the rapidity of recovery following cessation of aminoglycoside therapy is highly suggestive. A review of five patients who received only penicillin or a semisynthetic derivative of penicillin did not reveal any temporal deterioration with onset of penicillin therapy or improvement with cessation of penicillin therapy.


Monozygotic twinning and structural defects.

An excess of structural defects occurs in monozygotic twins compared in dizygotic twins or singletons. The excess is composed of three categories of defects. The first includes defects which are part of the MZ twinning, such as conjoined twins and some amorphous twins. In addition, all early embryonic malformations and malformation complexes such as sirenomelia mc. holoprosencephaly mc. and anencephaly mc are increased in MZ twins. The reason for this association is considered to be the common etiology for both the MZ twinning and the early malformation problem. MZ twins provide an excellent model for appreciating the spectra of particular malformation complexes, since the twins often have different gradations in severity of the same type of structural defect. The finding of both discordant and concordant MZ twins with Goldenhar, de Lange, and Rubinstein-Taybi syndromes suggests that these "syndromes" might be early malformation complexes. The other two categories are considered secondary to the MZ twinning process. The most unique category results from any vascular interchange between the MZ twins. Depending on their nature, vascular connections may give rise to reverse flow with acardiac status in one twin during early development, or to vascular disruptions from a deceased co-twin with intravascular coagulation causing embolization in the surviving co-twin. The latter defects may include microcephaly, porencephalic cysts, hydranencephaly, intestinal atresia, aplasia cutis, and limb amputation. Unequal growth may occur as a result of artery to vein placental anastomoses. The final category is deformations due to crowding in utero during late gestation. These do not differ from those in DZ twins.


Segmental "hypoplasia" of the kidney (Ask-Upmark).

Severe segmental renal atrophy with loss of parenchymal elements in small kidneys is commonly known as segmental hypoplasia. The scars are seen as cortical depressions overlying shrunken medullary pyramids and their dilated calyces, and are characterized histologically by colloid-filled tubular microcysts and a paucity or absence of glomeruli. This lesion has been identified in 17 patients, 11 female and 6 male, between 6 and 23 years of age. Eleven patients had hypertension, which developed in six while they were under observation. Thirteen had histories of urinary tract infection, and 16 had evidence of vesicoureteric reflux. Seven patients had impaired renal function (GFR less than 40 ml/minute/1.73 m2). Abnormal metanephric differentiation (dysplasia) in two specimens, one in association with posterior urethral valves, suggested an occasional intrauterine origin of the abnormality. Twelve patients had radiographic evidence of decreasing renal size over two to five years of observation, even after surgical correction of reflux, in four of them unaccompanied by infection. We conclude that segmental "hypoplasia" is an acquired lesion, although it sometimes has intrauterine origins, and that it is commonly associated with vesicoureteric reflux, even in the absence of demonstrable infection.