College women with differential linguistic-quantitative ability patterns: performance on two visual serial-search tasks.

Two groups of 14 college women, equated on College Entrance Examination Board Scholastic Aptitude Test scores but showing a discrepancy of at least 150 points between the scores on the Verbal and Mathematical Aptitude Test, were compared on two visual serial-search tasks; a 2 X 2 mixed factorial design was used. There was a trend in the direction of more rapid visual serial-search by the low linguistic-high quantitative subjects than for the high linguistic-low quantitative subjects. Consonant with earlier findings, visual serial-search time was significantly faster for number targets than for letter targets. Between ability patterns and target characteristics there was no significant interaction. The need to include more complex visual serial-tracking tasks in any reexamination of the observed results was noted.


Response bias in deaf and hearing subjects as a function of motivational factors.

This experiment assessed the effect of different payoff matrices on 6 deaf and 6 hearing subjects on a visual brightness discrimination task. Subjects were required to make forced-choice responses to three different monetary payoff conditions, designed to induce a liberal, a conservative, and an equal-bias response criterion, respectively. The results showed that the deaf did not select the superior response strategies they had exhibited in a previous study (Bross, 1979) on the effect of changes in stimulus probability. Furthermore, the deaf earned significantly less money than the controls for all three conditions, indicating that the introduction of motivational demands affects their response strategies adversely.


Visual pattern perception: a multidimensional analysis of development of children's reading skills.

This study was designed to assess the extent to which there are visual pattern processing deficits which are related to differential reading skill of young children. Discrimination problems were constructed using visual patterns with features known to be processed differentially by the central nervous system based upon neurophysiological data. Analysis of variance and multidimensional scaling techniques were used to analyze the discrimination latencies of kindergarten through third grade children (12 per grade) who were classified either as good or poor readers. The results show that there are no pattern-specific effects which discriminate good from poor readers. Rather, good readers process all patterns more efficiently than do poor readers, and efficiency improves with age for all readers studied. This suggests that the locus of the reading deficit occurs at levels in the nervous system beyond where pattern-feature processing occurs.


Representation of complex emotional and abstract meanings by simple forms.

Using curved and angular line drawings, several investigators found a relation between form and meaning in individuals reared before the age of television. In the present study 60 university students who had been exposed to television from earliest childhood were asked to indicate whether a curved or angular figure best represented each of 40 emotion or abstract concepts. For 36 of the concepts the frequencies were significantly different from a chance level, and it was concluded that television viewing had no adverse effect on the fittingness of form and meaning. Several possible explanations for the phenomenon are discussed.


Time-varied noise effects on color-word test performance.

The effects of continuous and time-varied 85 dBA broadband noise on the performance of a Stroop-type color-word test and a related word-reading task were investigated. 10 subjects served in one of three groups receiving either continuous, periodic, or aperiodic noise. All subjects performed in both low noise (65 dBA) and high noise (85 dBA) conditions on 80 trials of both word reading and color naming. Median reaction times in the word-reading task were unaffected by either noise intensity or the time-varied aspects of the noise. However, median reaction times in the color-naming task were significantly elevated in the 85-dBA noise condition. Also, reaction times in the high aperiodic noise condition were significantly elevated relative to the continuous and periodic noise conditions. Results are discussed within the framework of arousal, filter, and information theories.


An approach to prediction of performance using behavioral and physiological variables.

10 male, middle-distance runners selected for their potential or actual success in running 1500 metres were subjected to laboratory tests of VO2 max and run time at 85% VO2 max. Using the Eysenck Personality Inventory (Eysenck, 1962), data were collected from the runners from which they were given a score on the Extraversion/Introversion dimension of personality. Pearson product-moment correlations were computed between 1500 m. run times and VO2 max, 85% utilization of VO2 max, and Extraversion scores. The highest correlation was between Extraversion and the 1500-m. run (r = .75). The multiple correlation between times for the 1500-m. run and Extraversion with VO2 max was .77. The results support the value of building comprehensive profiles for the athlete which include not only physiological and anatomical variables but behavioral measures as well.


A new Visual Aesthetic Sensitivity Test (VAST): II. cross-cultural comparison between England and Japan.

A comparison was made of the scores of 171 Japanese boys and 156 Japanese girls, and of 204 English boys and 165 English girls, on the Visual Aesthetic Sensitivity Test. Also compared were 145 male and 163 female Japanese students, with 38 male and 73 female English students. Japanese children had scores significantly higher than English children, while Japanese students had scores significantly lower than English students. There was little evidence of age increments in score for either group of children. Difficulty levels of the 42 item-pairs were very similar in the two cultures, as were internal (split-half) reliabilities. It is concluded that cultural differences between the two countries, as far as visual aesthetic appreciation is concerned, seem at best minimal.


Relationships among spatial skills, communication skills, and field independence in deaf students.

The hypotheses that deaf students would be more field-dependent than hearing students and that their competence in communication skills would be positively related to field-independence were supported for a group of 77 male and 67 female deaf students. Step-wise multiple regression analyses of the data showed that for females spatial skills followed by communication skills were significant predictors of field-independence; for males spatial skills followed by the extent of hearing loss were significant predictors of field-independence. Sex differences found on tests of field-independence and spatial relations were consistent with those obtained from the hearing population. It was suggested that socialization experiences and competence in communication skills may influence development of field-independence in deaf students.


Validity of perceptions during recovery from maximal exercise in men and women.

The Borg Scale, widely used to measure perceptions of exercise, has not been validated for use during recovery. Heart rate was used as the validity criterion. 11 untrained men and 10 untrained women were run to exhaustion on a treadmill. Heart rate and recovery ratings were obtained at :15, :45, 1:15, 1:45, 2:30, 3:30 and 4:30 min. following exercise. No significant differences were observed between sexes for both heart rate and recovery ratings. Trend analysis showed recovery ratings to be linear between :45 and at 4:30 while heart rate is best described by two linear trends with a break point at 2:30. Percent recovery was significantly faster for recovery ratings at :45, 1:15, 1:45 and 4:30. Heart rate and recovery ratings were not significantly correlated at any time point. A perceptual scale should be designed which more closely approximates metabolic response during recovery.


Annoyance response of nonsmokers to cigarette smoke.

In three experiments, nonsmoking subjects rated their annoyance by task environments while either exposed or not exposed to ambient tobacco smoke. In Exps. 1 and 2 subjects rated annoyance with the environment while exposed to three intensities of noise, and in Exp. 3 subjects rated annoyance while performing multiplication problems under conditions of high and low task motivation. The source of the ambient smoke in Exp. 1 was a smoke pump. For Exps. 2 and 3, the source of the smoke was confederate subjects. No differences in annoyance were obtained in Exps. 1 and 2 as a function of exposure to smoke. Exp. 3 showed that nonsmokers' annoyance to a task environment is dependent upon task motivation and exposure to ambient smoke. In Exp. 3 nonsmokers exposed to smoke were more annoyed than those not exposed under low motivating conditions. When nonsmokers were highly motivated in the task environment those exposed to smoke were significantly less annoyed than those not exposed.


Perception and perceptual-motor integration: there is a difference.

Explored the independence of perceptual and perceptual-motor performance in a group of second graders with effects of chronological age and intelligence controlled. Resulting correlation indicated that 16% of the variance of one variable is predictable from the other variable, supporting the growing evidence that these two skills are to a large degree independent.


Effect of information feedback on temporal discrimination in concurrent and post-feedback measures.

College students estimated time intervals (5, 6, 7, 8, and 9 sec.) where one group (N = 20) received information feedback in terms of actual interval durations and a second group (N = 18) received no information. Theshold measures were then taken for all subjects using the method of constant stimuli (comparison stimuli of 5, 6, 7, 8, and 9 sec. and a 7-sec. standard). In addition to increased accuracy and consistency of judgments, the feedback group showed a decreasing Weber fraction during the estimation phase, while the Weber fraction for the no-feedback group increased. The feedback group retained only a slight advantage in subsequent threshold measures; group differences in difference thresholds and derived nonparametric estimates of d' were nonsignificant.


Variations in perception of short time intervals during menstrual cycle.

The hypothesis that women experience heightened sensitivity and responsivity premenstrually was tested by asking 10 women to produce short time intervals at four phases of the menstrual cycle. 10 men were assigned to "pseudo-cycles" and tested as a control. The test was based on the assumption that a greater sensitivity to stimuli is reflected in a "slowing down" of subjective time. The women produced the shortest time intervals three to four days before menses, confirming the hypothesis.


Hemisphere differences and judgments of simultaneity of brief light flashes.

A series of experiments was conducted to investigate the possibility of hemispheric specialization for judgments of the simultaneity of two light flashes. Right-handed subjects adjusted two light flashes until they appeared simultaneous. The comparison of measures derived from the two possible orders of the light flashes suggested that the right hemisphere of right-handed subjects performed the function of ordering visual stimuli in time. Two further experiments examined an alternative explanation, that of a left-to-right scanning mechanism, the results of which also suggested a hemisphere explanation. The results of these experiments are discussed in terms of previous research and theories which located a temporal ordering mechanism in the speech hemisphere.


A left-ear advantage for chords in non-musicians.

Contrasting with previous reports, left-ear advantage was found for recognition of chords by non-musicians (n = 16). It is suggested that the less memory is involved the more the effect may appear in musically naive subjects.


Schematic concept formation: psychophysical analysis of early reading skill.

The relation between the perception of class structure and reading skill was studied within the context of a schematic concept-formation task. Computer generation techniques were utilized to construct visual pattern-classification problems with controlled levels of inter-class pattern similarity of class discrimination difficulty. Children with reading problems were less efficient in their ability to assign patterns to classes than were children without reading problems. It was possible to assess reliably individual subjects' reading skill on the basis of their ability to perform the task.


The Slingerland Screening Tests for identifying children with specific language disability: screening for learning disabilities in first grade.

The responses on the Slingerland tests of 29 learning disabled and 11 nondisabled children in Grade 1 distinguished the two groups, except for copying (near vision). Copying (far vision) and auditory, visual, and kinesthetic perception and discrimination together were the strongest predictors of group membership.


Influence of an intertrial interval on sequential effects related to preparatory period duration for reaction time-task.

In reaction time tasks, where the moment of occurrence of the response signal is uncertain, the temporal constraints of preparatory processes imply that subjects distribute their preparation during the preparatory period. The notion of cost of preparation has been proposed to explain the time course of these processes. This experiment was run to determine the effect of the cost of preparation on a serial-RT task and on a RT task where a rest interval of various possible durations (3, 6, or 9 sec.) is introduced. 12 subjects were tested. Data show that the amount spent on preparation during a trial affects the subject's performance during the next trials. But an hypothesis about memory search must also be advanced to explain the effect of the rest interval on the relationship of RT and the current preparatory period.


Temporal duration as a function of information processing.

Estimation of duration has been shown to be a function of the amount and manner of organization of information processed during an interval. It was assumed that the use of an organizational schema to encode information reduces the actual amount of information stored. It was predicted that the use of an organizational schema will result in relatively shorter estimates of duration. Eighteen undergraduate subjects made estimates of intervals (.58 to 3.0 sec.) during which they watched film animations of moving geometric forms. In a second condition the same subjects were instructed to organize the animation as representing social interaction. An interaction showed that the use of an organizational schema to encode information resulted in smaller estimates for the longer intervals.


Dichhaptic perception of forms by normal adults.

Dichhaptic perception of nonsense forms was examined in familial righthanders. In Exp. 1, 15 males and 15 females performed similarly, obtaining a non-significant right-hand superiority with a 5-sec. memory interval between presentation of stimuli and their choice-recognition response. Individual differences in Block Design scaled scores but not State or Trait anxiety were related to hand performance for both sexes. One strategy on a questionnaire was related to performance of males. Exp. 2 was a replication with the memory interval removed. A significant right-hand superiority was obtained and different strategies were related to performance of males and females.


Development of the perception of invariants: substance and shape.

Three experiments investigated the perception of substance and shape as invariant properties of objects by three-month-old infants. In experiment 1, infants were habituated to two differently shaped objects undergoing a rigid motion. After habituation of the infants, the objects were presented undergoing a different rigid motion, or undergoing a deforming motion, or undergoing the same rigid motion. Habituation was maintained to the new rigid motion, indicating that the two rigid motions were perceived as sharing an invariant property. Dishabituation, on the other hand, occurred when a deforming motion followed a rigid one. In experiment 2, infants were habituated to one shape undergoing two different rigid motions. After habituation, the shape was changed but the same two motions continued. Dishabituation occurred, compared to a group with no shape change, indicating that shape is distinguished as an invariant property over two rigid motions. In experiment 3, habituation to a shape undergoing two rigid motions was followed by a new shape presented motionless, or the same shape presented motionless. Cessation of motion did not prevent recognition of shape as invariant. Two properties of an object, substance and shape, thus appear to be detectable as invariant in an event sequence, an instance of "phenomenal doubling" at an early age.


Scanning visual images: implications for the representation of space.

This study investigated whether reaction time to detect an item within an image increases as a monotonic function of the relative or the absolute distance from the starting item to the probed item with the image. It was found that when relative probed distances were manipulated and absolute distances kept constant and, conversely, when absolute distances were manipulated and relative distances kept constant, reaction times were invariant across relative distance but increased as a function of increasing absolute distance. This result may be interpreted either in terms of operations within an imaginal representation or in terms of operations on propositional statements underlying the image.


Flexibility in the choice of distinctive features in visual search with blocked and random designs.

An experiment is reported which demonstrates that the features used to detect a character in arrays of similar forms are a function of the stimulus context in which the target is embedded. With the use of blocked and randomised design it was shown that prior knowledge of the background aided search when the feature which was relevant for one backgroind was irrelevant for another, but no significant effect of prior knowledge was obtained when the same feature was useful for the backgrounds.


The effects of verbal meaning and response categorisation on the fragmentation of steadily fixated patterns.

Studies of steady visual stimulation have suggested that the subjective meaning of a stimulus may determine the form and degree of its perceptual fragmentation. This was tested for steady fixation by presenting a letter of the alphabet ("L") in a sequence of other letters which were either normally oriented or inverted. No evidence was found for greater stability in the former case. An investigation of the categorisation of subjective disappearances showed that, although the stability of pattern components was not determined by reporting these singly or in conjunction, the disappearances of the whole pattern were significantly increased by reporting only these as opposed to reporting disappearances of each component. Response to stimulated subjective disappearances also showed that the effect was due to the nature rather than the number of response categories. In the final experiment all subjects fixated a rotated letter, after half had received pretraining in the recognition of rotated letters. No effects of the pretraining were apparent, for either level of response categorisation, and it was concluded that the processes underlying subjective disappearances in steady fixation are not modified by the meaningfulness of a stimulus. The involvement of central processes was, however, indicated by the effects of response categorisation and the influence of simulated disappearances on pattern stability in a trial subsequent to their presentation.


Information used in judging impending collision.

Many subhuman species and human infants, children, and adults can use two-dimensional information of relative rate of angular-size change to anticipate collisions between the self and approaching objects or surfaces. But extant studies have not determined what information is used when subjects view simulated approach events providing two-dimensional information and three-dimensional information (distance and distance change), as well as lower-order visual information contained in real approach events. Three experiments suggest that, given these several possibilities, adults' judgments of collision time are best predicted by two-dimensional spatiotemporal values which are invariant over object sizes, distances traversed, approach velocities, and several lower-order variables such as absolute angular size. However, collision time is substantially underestimated, with absolute amount of underestimation increasing as a function of actual time-to-collision. Large constant errors and loss of judgment linearity beyond about 10 s to contact time suggest that current models of human performances based on use of time-to-collision information require modified assumptions of operator efficiency.


A new motion illusion.

Two instances of a new illusion of motion were discovered. In the first, when observers tracked a spot of light moving vertically in a field of stationary vertical lines, the lines appeared to move in the same direction as the spot. If observers did not track the spot, the lines appeared stationary. The second instance was designed to see if the same illusion would occur when the spot appeared to move as a result of induced motion. In this display a vertically moving grid of horizontal lines surrounded a stationary vertical line. A stationary spot of light could be projected on the line. If the subject fixated the spot, both spot and line appeared to move against the grid. If the spot was absent, the line appeared to move along with the grid. The implications of this illusion for theories of induced motion are discussed.


Illusory contours as the solution to a problem.

The perception of certain figures with illusory contours entails a reversal of figure and ground. It is hypothesized that this process occurs in two stages. First, some factor must suggest or cue the reversal. Experiments are described that isolate three such factors, namely, alignment of physically present contours, recognized incompletion of parts of the stimulus array, and set. Once cued, however, other experiments indicate that in a further stage of processing the solution is examined with respect to its compatibility with the stimulus display or with other preceptual properties to which the display gives rise. Only if such compatibility is present will the perception of a figure with illusory contours be maintained.


Cerebral asymmetries in random-dot stereopsis: reversal of direction with changes in dot size.

Visual field differences in stereoscopic form recognition using Julesz-type random dot stereograms were investigated. Dot size was varied in order to test the possibility that variations in the carrier dimension have contributed to past estimates of visual field differences. Twelve male and twelve female subjects, all right-handed, appeared for three test sessions-one with each different dot size. In each session the stimuli were flashed twenty-four times in each visual field, for 120 ms. Results showed no overall visual field effect, but a highly significant interaction between visual field and dot size. For small dots, left visual field superiority was observed, as previously reported by Durnford and Kimura. With large dots, however, the right visual field  was superior. This reversal of visual field differences  as a function of dot size implies that there is no consistent cerebral hemispheric specialization for stereopsis or stereoscopic form recognition per se. Instead, it appears that there is relative hemispheric specialization for responding to the carrier of stereoscopic information.


Surfaces with steep variations in depth pose difficulties for orientationally tuned disparity filters.

Surfaces possessing steep variations in depth present severe difficulties for orientationally tuned filter models of stereopsis. These difficulties are discussed in connection with a random-dot stereogram depicting a surface with steep horizontal corrugations. As expected on theoretical grounds, we find that a vertical +/- 45 degrees orientationally filtered version of this stereogram cannot be fused. Moreover, it is demonstrated that a horizontal +/- 45 degrees filtered version can be fused only with difficulty and its stereo percept is poor compared to that of the unfiltered original. It is concluded that orientated filters seem ill-designed to mediate the extraction of disparity cues, at least in the cases under consideration.


Individual differences in the visual component of prism adaptation.

The centrality of individual differences in the visual component of perceptual adaptation was examined in a massed-practice-terminal-exposure, prism-viewing paradigm. With positive (adaptive) adjustments in the judgment of the visual straight-ahead, target-pointing aftereffects were found to be equivalent to the sum of the visual and proprioceptive (head-arm) aftereffects. For subjects showing negative visual adjustments to prism exposure, the target-pointing aftereffect was not significantly different from the change in proprioception alone. Implications of these findings for hypotheses concerning the process of perceptual adaptation are discussed.


Adaptation effects on the apparent "squareness" of square-wave gratings.

Adaptation to a 9 cycles deg-1 sine wave makes the apparent brightness profile of a 3 cycles deg-1 square wave look less "square" even when it  does not look like that of a sine wave. Adaptation to a 3 cycles deg-1 sine wave has no noticeable effect. Hypotheses based on "excitation patterns" across spatial-frequency-selective channels can account for these results; it is not clear whether variations in local light adaptation can also account for them.


Symmetry perception and spatial-frequency channels.

It is known that the sum of a random-dot array with vertical bilateral symmetry and one with horizontal bilateral symmetry appears as a random array. Here we show that if the vertically and horizontally symmetrical arrays are spatially filtered, so that their respective spectra are 2 octaves apart, then their superposition does not appear random, but both symmetries can be simultaneously perceived. The low-band array has a stronger perceptual weight than the high-band array. These demonstrations give further evidence that frequency channels are before symmetry perception.


Effects of acute lactic acidosis on some hemodynamic and hematologic values in three cows.

Some hemodynamic and hematologic effects of acute experimental lactic acidemia in 3 healthy cows are presented. Lactic acidemia was induced by intravenous infusion of a 10% solution of racemic lactic acid. The prominent features of the acidification of the blood were increases in carotid artery blood pressure and responses to intravenously injected norepinephrine, slight bradycardia and slight hyperventilation. Intravascular hemolysis with hemoglobinuria was a constant finding. Otherwise, no adverse effects of the acidemia were noted. These changes were paralleled by a progressive fall in arterial blood pH, base excess and PCO2 and increasing venous blood L (+)-lactate concentrations A reasonable explanation for the hemodynamic effects of the acidemia is peripheral vasoconstriction elicited by either stimulation of the sympathetic nervous system or increased sensitivity of vasoconstrictive receptors. The results are discussed with special reference to primary lactic acidosis encountered in grain engorgement in ruminants and to the secondary lactic acidosis of shock. These conditions are characterized by hemoconcentration and hypovolemia. Therefore, the results of this study of healthy normovolemic cows may not be valid in the severely dehydrated, hemoconcentrated and acidemic cow as hypotension is reported in the literature in connection with ruminal acidosis in sheep.


Enema in the horse. Distribution and rehydrating effect.

In the first series of experiments enema containing a water soluble marker was given to two groups of horses fasted for 1 and 18 hours, respectively. The marker was only in 1 out of 14 experiments found orally of the pelvic flexure (Table II). Fasting seemed to facilitate the flow in oral direction. The results were discussed with the possible significance in the treatment of large intestinal impactions. In the second series the effect of enemas on water, electrolyte and acid-base status in the acute furosemide-dehydrated horse was studied. Moderate acidifying and hypokalemic effect was encountered, while no effect was demonstrated on the water balance. The choice of method is questioned, and no conclusion is given with relation to a rehydrating effect of enemas.


Arthrosis in the elbow joint of young rapidly growing dogs. III. Ununited medical coronoid process of the ulna and osteochondritis dissecans of the humeral condyle. Surgical procedure for correction and postoperative investigation.

A surgical procedure for medial arthrotomy in the elbow joint is described. Surgery was performed in an endeavour to remove an ununited coronoid process and/or a loose piece of cartilage from the humeral condyle. A long term follow up investigation of 58 operated and 20 unoperated dogs was undertaken. The prognosis of dogs operated upon because of osteochondritis dissecans of the humeral condyle, was fairly good; 11 of 15 dogs (73.3%) being reported as showing no signs of lameness. When dogs with the both diagnoses were judged together, the percentage of dogs reported not to be lame was 48.3 among operated dogs and 45 among unoperated dogs. However, dogs operated upon, recovered somewhat sooner than unoperated dogs. Of 38 dogs (58 joints) which were clinically and radiographically re-examined by the author, it was found that severe arthrosis (degree 3) developed in about 60% of the joints, no matter whether surgical treatment was carried out or not. However, 19 of these dogs were not lame, or only revealed lameness occasionally.


Renal and mammary excretion of sulfadimidine in buffaloes.

The renal and mammary excretion of sulfadimidine was investigated in 8 lactating buffaloes after intravenous administration. The results showed that sulfadimidine was bound to the proteins in plasma (39--59 per cent) and milk (5.5 per cent). The renal handling of sulfadimidine was influenced by the variations in the urinary pH and the concentration of non-protein-bound drug. From the results it is concluded that glomerular filtration, back diffusion and active tubular secretion are involved in the renal handling of sulfadimidine in buffaloes. The results of mammary excretion showed that sulfadimidine is excreted into milk of buffaloes in concentration lower than in plasma. The ratio between the concentration of sulfadimidine in milk and plasma increases when the pH of milk increases. The results are consistant with the theory that drugs are excreted through the mammary gland by passive diffusion.


[Red cell filterability, smoking and cardiovascular risk factors (author's transl)].

Red cell deformability, which allows cells of 7 mu diameter to flow through capillaries not larger than 3 mu, can be approached by the measure of blood filterability on nuclepore 5 mu filters. Filterability is reduced in arterial diseases. We have, in 72 patients, correlated red cell filterability, with the number of cardiovascular risk factors present high blood pressure, overweight, diabetes, hyperuricemia, hyperlipemia smoking). There is a statistical difference between groups with risk factors present as a whole and with O risk factor (p less than 0.01). The difference is highly significant between O and 4 risk factors (p less than 0.0005). Filterability decrease is also directly correlated with the number of cigarettes smoked per day (less than 0.05) and decrease is enhanced by smoking two cigarettes.


[The influence of blood glucose on the filtrability of red cells in diabets. Variations after connection to an artificial pancreas (author's transl)].

In 36 treated diabetics (15 with insulin, 21 with oral hypoglycaemic agents) without any detectable arterial atheromatous lesion, there was a negative correlation between the filtrability of red cells and blood glucose levels (r = - 0.60) on the one hand and, secondly, glycosylated haemoglobin levels (r = - 0.40). In 17 insulindependents diabetics connected to an artificial pancreas, normalisation of blood glucose was accompanied by a concomitant increase in the filtrability of red cells, and improvement of spontaneous platelet agregation. Good control of diabetes would thus appear to be necessary to reduce the incidence of microangiopathy.


[Progressive myoclonic encephalopathy in dialysis patients: presence of high concentrations of aluminium in the lysosomes of the cerebral cells (author's transl)].

Sampling of brain tissue of two patients who died of dialysis encephalopathy syndrome have been studied using a combined electron microscope-electron microprobe x-ray analyzer. X-ray microanalysis showed that aluminium is present in high concentration in lysosomes of brain cells. This concentration is approximately one thousand-fold that which is normally measured in the grey matter. In these lysosomes, aluminium is present in needle like microcrystalline form of 0.006 micron diameter and 0.08 micron long on the average; in these crystals, aluminium is associated with phosphorus in a ratio of one atom of aluminium per atom of phosphorus. Similar lesions have been observed in the rat after intraperitoneal injections of water-soluble aluminium salts.


[Type A1 branchydactyly. Study of one family (author's transl)].

Five members of a kindred with type A1 brachydactyly were ascertained. The middle phalanges of the last four fingers were short, rudimentary or absent, and the proximal phalanges of the thumbs and great toes were shortened. Emergence of the brachydactyly in the children of an unaffected woman suggested the possibility of a half chromatid mutation or of a premutation. The pedigree was then consistant with autosomal dominant inheritance with complete penetrance for brachydactyly.


[Hypouricaemia (author's transl)].

Hypouricaemia (blood level blow 2 mg/100 ml or 12 mumol/100 ml) is rarely observed, i.e., in less than 1% of hospitalized patients. Hypouricaemia can be induced by any of three mechanisms: a decrease in uric acid synthesis due to deficient xanthine oxydase (e.g., hereditary xanthinuria, severe liver disease, treatment with allopurinol); increased uricolysis due to drug therapy; increased urinary excretion of uric acid. This increased urinary excretion is due to abnormal uric acid transport in the proximal tubule. It is sometimes observed alone (primary hereditary anomaly of tubular uric acid transport, severe liver disease or neoplasia, drugs, or contrast media). It can also be observed in association with other proximal tubular anomalies, constituting a Fanconi syndrom. Among observations of hypouricaemia, 50% result from drug therapy and approximately 30% are secondary to liver diseases or neoplasia. It has no special clinical consequence. Nevertheless, the observation of hypouricaemia in a patient should indicate the possibility of drug intoxication or an underlying disease, in particular neoplasia. Measurement of uric acid clearance is a simple method of determining the mechanism responsible and of guiding diagnosis.


[Myocardial protection by perfusion in deep hypothermia (10 degrees C) with or without cardioplegia (author's transl)].

A technique of myocardial protection using a perfusion circuit in deep hypothermia via the ascending aorta or by selective cannulation of the coronaries has been used over a period of 2 years in almost 200 patients undergoing surgery requiring prolonged aortic clamping. It ensures rapid and homogeneous cooling of the myocardium (10-12 degrees C) and meets its reduced oxygen needs. It may be completed by cardioplegia (infusion of potassium chloride or lidocaine using an automatic syringe at a determined level). This simple technique permits a rapid spontaneous return of normal effective cardiac action. No low cardiac output syndromes have been seen since it has been used. Laboratory, histological, biochemical and haemodynamic studies carried out have confirmed its harmless nature.


[Data processing in clinical nuclear medicine (author's transl)].

Since the introduction of data processing into clinical nuclear medicine, significant advances could be achieved above all through the development of quantitative gamma camera scintigraphy, which is nowadays one of the most important fields of computer application. The technological properties of an adequate computer system for nuclear medicine use are dependent on a scale on the necessities of gamma camera sequential scintigraphy. If the computer capacity to carry out fast sequential scintigraphy is available, the system can be used for all modern scintigraphic procedures as well as for other tasks. If we look back on the experience gathered in more than ten years, the following areas can be named in which the use of computers appears worthwile and desirable: 1. scintigraphic diagnostics 2. functional diagnostics 3. medical record printout 4. operational management of the department, documentation and retrieval of the patients data 5. planning of therapy. Because of the importance of quantitative sequential scintigraphy, in many nuclear medicine departments two or more gamma camera computer systems are used. For reasons of costs, however, it will not be justifiable to connect each gamma camera with a separate effective data system. Therefore systems have been tested in which several gamma cameras are connected to a host computer via microprocessor-controlled buffer systems and by means of DMA interfaces. From practical experience, critera were worked out to draw up a computer concept for data processing in clinical nuclear medicine.


[Application of harmonic analysis in quantitative heart scintigraphy (author's transl)].

Quantitative scintigraphy of the heart after equilibrium distribution of a radioactive tracer permits the measurement of time activity curves in the left ventricle during a representative heart cycle with great statistical accuracy. In the range of ventricular volumes which usually occur, the time activity curve corresponds with sufficient accuracy to the ventricular volume variation during one heart cycle. In cardiological terms, the parameters ejection fraction as well as maximum rates of ejection and filling have proved useful for evaluation of hemodynamic performance. By application of Fourier's analysis, criteria are to be attained in addition for evaluation of the volume curve as a whole. Thus the entire information contained in the volume curve is completely described in a Fourier spectrum. Because of the statistical noise, the volume curves drawn up from scintigraphic techniques require smoothing procedures, especially in determination of the differential quotients of ejection and filling rate. Smoothing by means of sliding average procedures causes a systematic deformation of the systolic dip and other similar regions of the curve, since the curve smoothened in this way does not converge towards the original curve at these points. Resynthesis after Fouier transformation seems to be an ideal method of smoothing because of its convergence in the minimum quadratic error for the type of function concerned.


[Time resolution of scintigraphically determined left ventricular volume curves (author's transl)].

In 25 patients with angiographically proven coronary heart disease and in 15 patients without heart disease, gated cardiac blood pool scintigraphy was done with 15 mCi 99mTc-HSA in LAO projection. Scintigraphic data were collected in list mode by means of a gamma camera connected to a computer system (Siemens 330). A cumulative scintigram scintigram sequence with a time resolution of 100, 50 and 25 frames/sec was constructed using several hundred heart cycles of equal duration. After background correction volume curves of the left ventricle with a time resolution of 25, 50 and 100 Hz were obtained and the following parameters of these curves were compaired: ejection fraction, maximum ejection rate and maximum filling rate. It could be demonstrated that smoothing by sliding average requires a time resolution of at least 50 Hz, whereas in volume curves smoothed by Fourier-Analysis a time resolution of only 25 Hz is necessary. However, using a time resolution of 25 Hz, the course of the volume curve can not always be clearly demonstrated, so that time resolution of 50 Hz combined with Fourier-Analysis for the gated cardiac blood pool scintigraphy is preferred.


[Accuracy of liver scintigraphy in focal liver disease; a comparison with postmortem studies in 159 cases (author's transl)].

In recent literature numerous papers have been published concerning the accuracy of scintigraphic detection of liver metastases. Unfortunately however, the problem of false positive results is not particularly discussed in these papers. Because of the lack of information it was our aim to compare our own scintigraphic results with postmortem histopathological findings. Our investigations were carried out in 139 patients with various types of malignancy. Included in the investigations were 20 patients with primary liver tumor. The interval between scintigraphic examination and the histological verification ranged from 3 days to 1 year. In 62 of the patients with liver metastases, histopathology revealed liver metastases, while 77 patients showed no liver involvement. We arrived at the correct diagnosis "liver metastasis" in 50 out of 62 patients (80.6%). False negative scintigrams (19.4%) were found in most of the respective cases when diffuse malignant involvement such as leukemia and Hodgkin's disease was present, and also when the size of the metastases was less than 2 cm in diameter. Fifty six out of 77 patients (72.7%) without histopathological evidence of liver metastases revealed negative scintigrams. Twenty one (27.3%) false positive scintigrams were mostly due to (diffuse) nonmalignant disease e.g. fibrosis and cirrhosis. The overall accuracy of liver scintigraphy in our study was 76.2%. In 18 of 20 (90%) patients with focal liver disease correct diagnosis was established. 7 patients with benign liver tumors and 11 of 13 patients with hepatocellular carcinoma showed focal defects. Considering the fact that liver scintigraphy is a non-invasive procedure, it can be recommended as screening method. In connection with sonography and computer tomography liver scintigraphy can undoubtedly improve the diagnostic accuracy in detecting liver metastases and primary liver tumors.


[Investigations on 131I-hippurate-clearance in obstructive-uropathy; extraction of para-aminohippuric acid and 131I-hippurate in the acutely obstructed canine kidney (author's transl)].

The results of more recent clinical and experimental investigations have thrown doubt on the usefulness of determining the individual 131I-hippurate clearance for evaluation of the function of acutely obstructed kidneys. There is a significant difference (5% level) between the kidney performance determined with external measurement on the one hand and with PAH and 125I-hippurate clearance in the steady state on the other. With the steady state method, the restriction of function to be expected in consequence of urinary obstruction is demonstrated, whereas with simultaneous measurement with catheterless 131I-hippurate clearance, an increase in function is detected. In the clearance studies carried out in the conventional way with PAH and 125I-hippurate, it was difficult to determine quantitatively the urine produced during urinary obstruction. The renal extraction of p-aminohippuric acid and 131I-hippurate was therefore determined in simultaneous measurement in six dogs before and after acute urinary obstruction with a constant plasma level of the test substances. The results obtained with this very elaborate method which is, however, independent of urine collection show that an acute urinary obstruction leads to a decrease of renal extraction both of PAH and of 131I-hippurate. Since with conventional clearance, the measurement result is proportional to the amount of substance excreted with the urine, a restriction of function must also result with the steady state methods in determining the performance of acutely obstructed kidneys. The results of the extraction investigations hence confirm the results of the clearance studies mentioned. In addition, they show that the "increase" of renal performance immediately after an experimentally induced urinary obstruction repeatedly found with catheterless determination of 131I-hippurate-clearance cannot be explained by a different kinetic behavior of PAH and 131I-hippurate in the acutely obstructed kidney.


[The influence of vitamin B 12 premedication on the result of the Schilling test (author's transl)].

The effect of previous administration of vitamin B 12 on the Schilling test was examined in 10 patients, repeating the test during and 10 days after vitamin B 12 treatment. Under vitamin B 12 medication, the patients showed a significantly decreased vitamin B 12 urinary excretion. Ten days after vitamin B 12, repeat Schilling test demonstrated comparable results with baseline values except for one patient, who persistently had a low value.


[Bone scintigraphy with 99mTc-methylene diphosphonate in parodontopathy (author's transl)].

In a total of 20 patients (of these 8 without parodontopathy and 12 with parodontitis marginalis profunda), a quantitative scintigraphy of the jaw bones was carried out after application of 99mTc-methylene diphosphonate with a gamma camera computer system. In 8 patients without parodontopathies, approximately the same metabolic activity in the bone was found in the os occipitale as well as in the mandible and maxilla. The 12 patients with parodontitis marginalis profunda showed in contrast to this an appreciable raised bone metabolism in the region of the affected jaw bone. This finding was in agreement with corresponding alterations in the X-ray of the jaw. The use of bone scintigraphy in marginal parodontopathies thus provides in addition to the radiological finding information on processes of bone transformation and degradation which can be registered quantitatively. Digital analysis enables control of the course of therapie.


[Morphological and functional evaluation criteria of hepatobiliary functional scintigraphy with 99mTc-diethyl-IDA in hepatocellular jaundice].

In 31 patients with histologically proven hepatocellular jaundice hepatobiliary scintigraphy with Tc-99m labelled IDA derivatives was performed. Results were classified under morphological (demonstration of liver parenchyma, ductus choledochus, bile ducts, gallbladder, kidney) and functional (Tmax, half time of bile excretion, appearance of activity in ductus choledochus, gallbladder, and intestines) criteria. The liver parenchyma could be demonstrated in 90.3% of cases, ductus choledochus in 71%, and the gallbladder in 72.4%. The type of tracer excretion into the intestines showed 9.5% activity accumulation in the gallbladder with late bile excretion into the intestines and 90.5% early activity excretion into the duodenum with late filling of the gallbladder. The intrahepatic bile ducts were demonstrated in 22.6% (left hepatic duct) and 6.5% (right hepatic duct). In 35.5% of cases the kidneys were still visible after 15 min p.i. All cases showed - sometimes delayed - bile excretion into the GI tract. The time of appearance of activity in ductus choledochus (18.4 min) and gallbladder (39.5 min) was delayed. The liver histogram showed likewise delayed values concerning Tmax (14.3 min) and half life of tracer excretion (greater than 30 min) when compared to controls. The differentiation of hepatocellular jaundice from obstructive jaundice is possible by the demonstration of bile excretion into the intestines, normal width of the bile ducts, and filling of the gallbladder.


[The normal liver-spleen scintigram with the gamma camera (author's transl)].

In 104 patients without liver disease, liver spleen scintigrams were analysed according to uniform criteria. The scintigrams were taken after application of 99mTc-sulfur colloid in at least six projections with the gamma camera and coupled data processing. As a significant difference compared to scanner scintigraphy, a non-homogeneous storage pattern is frequently also found in the healthy liver, especially in the ventral projection. Superimpositions or impressions caused by extra- or intrahepatic structures were also more frequent and more pronounced than with scanner scintigraphy. As expected, there were no appreciable differences with regard to the liver forms. The following quantitative parameters were determined (mean +/- SD): maximum vertical diameter of the liver: 199 +/- 20.0 mm, maximum horizontal diameter: 219 +/- 19.8 mm; liver area (ventral projection): 187 +/- 27.3 cm2; spleen area (dorsal projection): 55.3 +/- 15.9 cm2; index of liver size (liver area divided by the normal weight of the patient as determined from a given table): mean +/- SD = 2.69 +/- 0.58 (ventral projection); spleen area index (spleen area divded by body surface): mean = 3.03 +/- 0.81 (dorsal projection). The choice of projection did not have any appreciable effect on the area dimensions and indices, so that with super-imposition of organs these values can be determined with sufficient accuracy even from oblique projections.


[Animal experiments with 99mTc-diethyl-HIDA in acute complete bile duct occlusion (author's transl)].

In order to establish whether a complete obstructive jaundice can abolish the accumulation of diethyl-HIDA (EHIDA) in the liver parenchyma, the common bile duct was ligated in 14 mongrel dogs. Before as well as at regular intervals after ligature of the common bile duct, a sequence scintigraphy was performed with 2 mCi 99mTc-EHIDA. For evaluation, time-activity curves (Tmax, T1/2), and analogue scintigrams as well as laboratory parameters were used for assessment. Up to seven weeks after ligation of the common bile duct, there was a marked accumulation of EHIDA in the liver parenchyma. The relative liver uptake (liver/background ratio) fell from 8.9 to 2.7, whereas conversely the cholestasis indicators aP and bilirubine rose markedly. Tmax did not show any significant alterations, whereas T1/2 was prolonged from about one week after ligation. Because of the duct ligation, there was no excretion of activity into the intestines. Immediately after ligation of the common bile duct, the gallbladder was shown up as a "hot" area in which the majority of the applied activity appeared from about one hour p.i. Begining with the fifth to the seventh day after ligation, the gallbladder was seen as a "cold" area in the liver paraenchyma. Bilirubine and aP were raised by about 50 times the initial value. With longer lasting cholestasis, the scintigram no longer altered whereas bilirubine and aP rose further. Histological examination after ligation for more than five weeks showed slight alterations as a whole. Gamma-GT and in particular GPT were likewise slightly raised compared to bilirubine and aP. The conclusion was drawn from this that the good accumulation of EHIDA in the liver parenchyma which is to be observed without exception even in cholestasis lasting for several weeks could be explained by a relatively slight hepatocellular damage. Only when there is a consecutive parenchymal damage in extrahepatic jaundice, accumulation of EHIDA in the liver can be abolished.


Necrotic changes of the adrenal cortex following orthostatic collapse in rabbits.

The adreal gland was studied in 56 adult male rabbits; 44 had been subjected to orthostatic collapse, and 12 served as controls. The animals either died from collapse or were sacrificed at regular intervals up to 30 days after the experimental procedure. Nuclear pyknosis was seen in cortical cells of animals dying in collapse. At 6 or more hours following collapse, necrosis was found involving single cells, or rarely small groups of cells mainly in the zona fasciculata. Regenerative areas were present at 7 and 15 days after collapse. This necrosis may be related to a nutritive disturbance, largely hypoxic in nature (hypovolemia with blood stasis and thrombosis). The adrenal medulla showed only degranulation.


Disseminated intravascular coagulation in autopsy cases. Its incidence and clinicopathologic significance.

In a study of 1729 consecutive autopsies, the histopathologic diagnosis of disseminated intravascular coagulation (DIC) confirmed by the presence of microthrombi in more than two organs was made in 51 cases. Among them, 38 cases (74.5%) were clinically not suspected of having DIC. Microthrombi were most frequent in the kidneys, followed by the lungs, spleen, adrenals, heart, brain, and liver, in descending order of frequency. Furthermore, a wide variety of visceral lesions was another important histologic feature of DIC. Kidney lesions assumed a position of prime importance, and special attention was given to the high frequency of acute renal failure due to so-called acute tubular necrosis and bilateral renal cortical necrosis. Infections, often associated with shock, and malignancies were the most common underlying causes of DIC. DIC is a frequent, often fatal pathophysiologic condition complicating many disorders. The true incidence of DIC at autopsy may be higher. It should be noted that demonstration of microthrombi and visceral alterations related to intravascular clotting is important for the evaluation of cases suspected of having DIC.


Collagen dysplasia and matrix vesicles. Researches with the electron microscope into the problem of so-called "weakness of the vessel wall".

Quite diverse pathological changes of the wall of a blood-vessel can lead to quantitatively and qualitatively altered collagen, as well as to the production of matrix vesicles. It can be demonstrated morphologically that changes--particularly qualitative changes--in collagen are accompanied by a more or less severe loss of function. Possible causal connections between the appearance simultaneously of matrix vesicles (in which lysosomal enzymes can be demonstrated) and altered vascular collagen are discussed.


The endothelial surface of large veins of rabbit: scanning electron microscopic observations.

The following veins of the rabbit were fixed by perfusion and studied systematically by scanning electron microscopy: sagittal sinus, confluence of sinuses, external jugular vein, superior vena cava, inferior vena cava, greater saphenous, and femoral veins. One result is that the shape and arrangement of endothelial cells of the veins are obviously influenced by hemodynamic shear forces. Two types of subendothelial fibres were demonstrated: "cross-fibers" which correspond to the circular inner muscle cells of the media, and "longitudinal fibers" which correspond to the intimal meshwork of connective tissue fibers. Regional differences are demonstrated in the occurrence of these fibres. Moreover, five morphologically different venous valve types are observed. The functional significance of these different valve types is not yet known.


Duct elastosis in infiltrating carcinoma of the breast.

Duct elastosis was studied in 219 patients subjected to radical mastectomy for infiltrating carcinoma of the breast, with a 10-year follow-up. Duct elastosis is a frequent finding in infiltrating breast cancer (65% of our cases). It develops in tumors of all three grades of malignancy, but it is more frequent in tumors of low grade malignancy (76% and 74% in grades I and II, respectively, and 47% in grade III tumors). In spite of their greater incidence in low malignancy tumors, the elastotic cases have a greater metastatic ratio than the non-elastotic cases (66% vs 45%). The elastotic cases also contain a significantly greater proportion of scirrhous tumors than the non-elastotic cases (86% vs. 32%). Duct elastosis and scirrhous reaction are two processes which develop in parallel, but are not related etiologically. They seem to be correlated with more advanced stages of the neoplastic disease. The influence of duct elastosis upon the ten year survival of the patients is unfavorable. this influence is not direct, and it is particularly evident in the metastatic cases. It seems to be related to the greater duration of the neoplastic disease and to the slow clinical course of tumors of low degree of malignancy.


[The cytologic differentiation of prostatis (author's transl)].

Cytologists are often confronted with unexpected prostatitis in aspiration biopsy smears, because clinically prostatitis may lead to suspicious induration of the prostate similar to carcinoma and therefore subject to diagnostic biopsy. The question is whether cytodiagnosis is a reliable method for the exact morphologic diagnosis of prostatitis. The following paper attempts to answer this question. The basis of our cytologic differentiation of prostatitis was a series of 129 cases of prostatitis in 664 aspiration biopsies according to Franzén. In 82 of these 129 cases, we had simultaneously performed a transrectal needle punch biopsy, which allowed a diagnostic comparison between the cytologic and histologic diagnosis with special reference to the reliability of cytology. Epithelial atypias were classified into 4 grades: Grade 1: No atypia; Grade 2: Slight atypia; Grade 3: Marked atypia; Grade 4: Malignant epithelium. Cytomorphologic characteristics of each grade are described. We found 6 different types in 4 main groups of prostatitis: 1. Acute prostatitis, purulent and abscessing types. 2. Chronic prostatitis. 3. Chronic relapsing prostatitis. 4. Granulomatous prostatitis, non specific and specific types. All types showed classic cytomorphologic inflammatory criteria. Marked atypias were found in group 3 and 4. Differential diagnosis with respect to carcinoma is not difficult, however, because marked atypias in these groups of prostatitis almost always appear focally. The diagnostic agreement between cytology and histology in 82 cases was found to be 87,6%. Our results showed that prostatis may be adequately diagnosed with cytology and may be differentiated into 6 different types. However, differentiation between periductal and interstitial forms of chronic prostatitis is impossible with cytology. Reliable cytodiagnosis of prostatitis requires a good aspiration smear, so that at least one half of slide is covered with material from the prostate. Furthermore, epithelial atypias must be present to prove the presence of prostatitis. Because of the good reliability of the cytologic differentiation of prostatitis, aspiration biopsy may be a valuable aid to the clinician in the primary diagnosis of prostatitis, especially the chronic type, which currently is sometimes uncertain.


[The current status of neuropathology in the Federal Republic of Germany 1979 (author's transl)].

This article describes changes in neuropathologic work towards a more intravital diagnostic aid, the increase in university neuropathologic departments, and the increased amount of neuropathology in teaching and examinations. These positive developments contrast with some genuine problems: the clinically oriented departments of neuropathology in some big research centers have been closed or altered and the personal staff of the university departments has been reduced. Subspeciality training in neuropathology within pathology should be supplemented by the possibility of entering neuropathology by way of neurology and psychiatry. Neuropathology should be connected to the neurosciences since this is the prerequisite to attain and maintain international research standards. However, the conditions necessary to achieve this aim personally and institutionally should be made available to all pathologists, clinicians, and administrators concerned with this subject.


[Comparative evaluation of biodestruction of polyurethanes synthetized on the basis of simple and complex polyesters].

In model liquids and experimental animals (rats, rabbits) with the aid of physico-mechanical and histological methods (using interferentially polarizating microscopy) a comparative evaluation was made of the biodestruction of polyurethanes from synthetized simple and complex polyesters. The tissue reaction to intra-abdominal, intramuscular and subcutaneous implantation of perforated stripes of A-19 and Nr. 36 polymer was moderate. Two weeks post-operative increased volumetric biodestruction of the polymers was observed. The course was different in various standards and depended upon the chemical structure of the polymers. Taking into account the slight macrophage tissue reaction, in counterdistinction to the significant volumetric biodestruction which envolved the entire width of the polymer strip, it is assumed that the destruction of the investigated polyurethane composition (adhesive KL-3) takes place by hydrolysis 3 to 6 months post-implant.


[Behavior of glycoproteins and blood serum proteins in rats after PVC implantation].

Determination of soluble protein level and bound sialic acid in 0,15 M SSA (seromucoid) as well as of protein levels and total sialic acid (NANA) were made both in blood serum and serous fluid. These tests were performed before and after subcutaneous and intra-abdominal implantation of different PVC samples. The subcutaneous implantation of samples caused the appearance of serous fluid and subsequently inflammation characterized by an increase of levels of sialic acid and seromucoid--the so-called "acute protein reaction". There were also observed the increased electrophoretic alpha 1, alpha 2 and beta globulin levels. Intra-abdominal implantation caused a decrease in the sialic acid level. Also the albumin fraction decreased but the concentration of the alpha 1 globulin fraction stayed within normal limits.


[Medico-physiological basis of functional properties and classification of elastic products for prevention and treatment of chronic diseases of veins of the lower limbs].

Chronic diseases of the venous system of the lower extremities and concomitant disorders in haemodynamics and vessel architecture are discussed. Data are presented suggesting correlation between the disease frequency and sex, age or profession. There are also discussed the problems of prophylaxis and treatment of these diseases, with particular reference to elastic man-made fiber products. On the basis of the presented data a classification scheme was made; there are also given the work properties and indications concerning the use of various elastic textiles for prophylaxis and treatment of venous system diseases.


In vitro studies on the role of the macrophages of resistant and susceptible chickens with Marek's disease.

Macrophages, from susceptible S- and resistant K-strain White Leghorn chickens, were studied in vitro to determine their contribution to the dynamics of Marek's disease (MD) and possible role in genetic resistance to this disease. In relation to basic macrophage properties (morphology, cell spreading, enzyme levels, pinocytosis, and phagocytosis) there were no significant differences between S- and K-strain macrophages. Both macrophage strains were observed to respond to JM virus by phagocytic responses, but no viral replication or transference of infectivity was observed within inoculated macrophage cultures. In general, there were no differences between S- and K-strain macrophages in vitro that may account for the genetic resistance or susceptibility to MD.


Anticoccidial activity of narasin in battery raised broiler chickens.

The anticoccidial activity of the ionophorus antibiotic narasin was tested against six species of coccidia (Eimeria acervulina, Eimeria mivati, Eimeria maxima, Eimeria necatrix, Eimeria brunetti, and Eimeria tenella) in battery-raised broilers. Feeding ration medicated with 60, 80, or 100 ppm narasin significantly improved weight gains during the periods of D 0 to D7 and D 0 to D 14 (D 0 = day of inoculation with sporulated oocysts), compared with the weight gains in corresponding inoculated groups fed unmedicated feed. A similar protective effect of the medication was seen with feed conversion ratios (feed consumed/bird weight) and coccidiosis-induced mortality. With most species studied, 40 and 60 ppm narasin was not as efficacious as 80 or 100 ppm. The maximum numerial improvement in weight gain and feed conversion ratio was with 80 ppm narasin. Gross intestinal lesion scores were reduced by medication compared with the scores in birds fed unmedicated feed. The overall trend was for a larger reduction in lesion score with higher drug levels. Narasin at 80 or 100 ppm was generally more effective in controlling individual or mixed species infections of coccidia than 99 ppm monensin.


Enhancement of the anticoccidial activity of polyether antibiotics in chickens by tiamulin.

The anticoccidial activities of monensin and lasalocid have been studied separately and in combination with tiamulin, a new pleuromutilin derivative. Combinations of constant tiamulin concentration (.0125%) in drinking water with various levels of polyether anticoccidials (6.3 to 125 ppm) in feed and conversely of constant levels of anticoccidials with various concentrations of tiamulin were used. The prophylactic efficacy of these combined treatments in battery raised broiler chickens infected with Eimeria tenella was evaluated. Assessment of the parameters mortality, weight gain, dropping scores, lesion scores, and oocyst output showed that simultaneous application of tiamulin significantly improved the anticoccidial activity of the polyethers. As tiamulin alone is without anticoccidial activity, this phenomenon was considered to result from an interaction between tiamulin and the polyethers leading to a slower metabolic degradation of the latter. Thus tissue levels adequate for maximum anticoccidial activity would be attained with lower polyether dose levels. Experiments using isolated perfused rat liver showed that elimination of monensin was reduced by 60% in the presence of tiamulin.


Specific immune gammaglobulin in the control of Mycoplasma meleagridis.

Turkey embryos naturally infected with Mycoplasma meleagridis were treated with different fractions of turkey immunoglobulins obtained from either abattoir or hyperimmune sera. The whole crude globulin fraction, IgG or IgM, were injected directly into the yolk sac of infected embryos. Embryos that died during incubation were broken out, aged, and the yolk sac contents cultured for M. meleagridis. All globulin treatments significantly reduced embryo mortality; purified IgG from abattoir sera appeared to be the most effective in this regard, whereas the crude globulin fraction from the same source was least effective. All surviving poults were kept under observation for 21 days after hatching and monitored for further mortality, presence of skeletal deformities, airsacculitis, and serological presence of M. meleagridis. On the basis of these data it is readily apparent that injection of homologous specific immune gammaglobulins may be an attractive method for enhancing passive immunity transfer and thereby reducing the deleterious effects of egg-transmitted M. meleagridis. Of particular significance is the finding that globulin fractions from naturally immune turkeys offer quantitatively similar protection as compared to those derived from hyperimmune birds.


Fatty acid binding protein in the intestine of the chicken.

The mucosa of the mesenteric intestine of the chicken has been found to contain a fatty acid binding protein (FABP) with a molecular weight of less than 12,400. The protein is present in the newly hatched chick before ingestion of feed and in the adult bird. When a low-fat diet is fed, the concentration of the FABP is highest in the proximal portion of the intestine and decreases posteriorly. When a high-fat diet is fed, an increase occurs in the amount of FABP in the lower section of the intestine.


Effect of Eimeria species on the appearance of radioactivity in the blood of chicks fed radio-labeled glucose or 3-0-methyl-D-glucose.

Results of five trials with four species of coccidia (Eimeria acervulina, E. necatrix, E. tenella, and E. brunetti) failed to demonstrate any interference with glucose absorption in the parasitized intestines of intact chick hosts. In addition, circulating blood radioactivity in severely parasitized chicks, as evidenced by weight gain data and intestinal lesion scores, was significantly higher than that in control chicks following oral administration of 14C-glucose or 3-0-methyl-D-14C-glucose at 6 days postinfection. During the recovery phase of the infection (14 to 21 days postinfection), severely infected chicks rapidly gained weight and the blood radioactivity of parasitized chicks was consistently higher than that of uninfected control chicks. No significant differences in weight or blood radioactivity were observed during the post-recovery period (28 to 35 days postinfection).


Passage of feed through the adult rooster.

Five experiments were made to measure the time required for feed residues to clear the alimentary canal. The cumulative production of excreta dry matter was the primary criterion of measurement although attempts were made to adopt a stained particle technique. The latter was confounded by the production of metabolic and endogenous wastes. When full-fed adult roosters were taken off feed the residues within their alimentary canals were voided within 24 hr. Subsequent experiments involved placing known quantities of feed in the crops of starved roosters and measuring excreta production. Finely ground corn, wheat, oats, and barley (30 g) cleared the alimentary canal in 24 hr. The amount of wheat or wheat bran (10, 20, 30 g) placed in the crop affected the rate of passage but clearance was completed within 24 hr. A confounding factor was that the production of metabolic and endogenous waste decreased with the degree of starvation which was a function of feed input. Corrections based on the excreta production of negative control birds were not wholly satisfactory. The rate of excreta production was affected by the duration of starvation prior to the feeding of coarsely ground corn, soybean meal, and meat meal. The time of feeding also had a small effect. However, neither variable was of practical importance. It was found that while corn and soybean meal resideus cleared the alimentary canal in 24 hr meat meal required about 30 hr. Alfalfa, fish meal, and wheat fed as pellets produced more excreta than when fed as meals. Pellets appeared to have the faster rate of passage through the alimentary canal. Both alfalfa and fish meal required more than 24 hr to pass through the birds.


An improved transbuccal approach for hypophysectomy in the domestic fowl.

The present paper describes an improved transbuccal approach for hypophysectomy in the domestic fowl. With this technique, the operative procedures are the same as in the transbuccal approach of Hill and Parkes (1934), except that the drilling angle is the same as in the oral approach of Rothchild (1948a,b), since the present anatomical investigation indicates that the hypophysis lies at an angle of 45 degrees to the surface of the palate. An apparatus that was made to restrain the fowl head facilitates the operative procedure; even a novice can perform fowl hypophysectomy in more than 70% of the cases.


Evaluation of ammonia stress and coccidiosis on broiler performance.

Eighty broiler chickens were randomly assigned to each of 12 chambers in a controlled environment poultry facility. Ammonia gas was injected at 0, 50, or 100 ppm from 28 to 53 days of age. All chicks, except the control pens, were innoculated with coccidia at 36 days of age. No significant differences were found in mortality, but weight gains were significantly reduced in chambers that received ammonia gas. This was probably due to the increase in severity of air sac and intestinal lesions in the ammonia pens.


The effect of hypophysectomy upon corticosterone-induced ovulation in the hen (Gallus domesticus).

When the ovary of a laying hen contains a mature follicle, ovulation can be induced by an injection of corticosterone. The dose which is required to consistently induce a premature ovulation causes the plasma concentration of corticosterone in the peripheral blood to rise to levels which are higher than those normally observed during the ovulation cycle. The accompanying rise and fall in progesterone which follows an injection of corticosterone. It was concluded that the pituitary gland for both ovulation and progesterone secretion to occur.


Safety evaluation of salinomycin in broiler chickens reared in floor pens.

Salinomycin (Coxistac), a new broad spectrum anticoccidial, was tested in broilers reared in floor pens for safety at 50, 60, 80, 100, and 160 ppm fed continuously from 1 to 56 days of age. Four trials were conducted. Comparisons were made to unmedicated controls and in three trials to monensin to monensin at 80, 100, and 121 ppm. The weight gains at 50 and 60 ppm of salinomycin and 80 and 100 ppm of monensin were statistically comparable and equivalent to or better than controls. The weight gain at 80 ppm of salinomycin was slightly below controls but comparable to 121 ppm monensin. Levels of 100 and 160 ppm of salinomycin depressed weight gain. Feed conversion for all treatments except 160 ppm salinomycin were comparable.


Testicular response of non-breeding pheasants to human chorionic gonadotropin, chicken pituitary extract, and photoperiod.

This investigation was designed to compare the testicular response of non-breeding pheasants to human chorionic gonadotropin (HCG), chicken pituitary extract (CPE), and extended photoperiod exposure (20L:4D) by analyzing testicular weights, testicular histology, and plasma testosterone levels. Exposure to 20L:4D increased testicular weights and plasma testosterone levels significantly (P less than .01) and recovered spermatogenesis completely. Injections of CPE increased testicular weights (P less than .01) and recovered spermatogenesis partially, but had no significant effect on plasma testosterone levels. Effects of HCG were non-significant. It is suggested that either doses of HCG and CPE used in this study were not enough or non-breeding pheasants require pheasant gonadotropins for the complete recovery of testicular function.


New observations on the structure of the hen ovum at ovulation.

Scanning electron microscopy of the perivitelline layer (PL) of a hen body cavity ovum revealed dispersed groups of atrophied granulosa cells. Those overlying the animal pole were flattened and had numerous ramifying processes which penetrated the porous ground substance of the PL. Alternatively, the granulosa cells overlying the vegetal pole were rounded and formed fewer processes which penetrated a nonporous ground substance. The latter observation suggests that the PL is not structurally uniform in all ova.


[Tumours markers. Calcitonin and carcinoembryonic antigen in medullary carcinoma of the thyroid (author's transl)].

Medullary carcinoma of the thyroid (MCT) is characterized by high circulating levels of calcitonin (CT) and of carcinoembryonic antigen (CEA), these markers enable the diagnosis of the tumour, the assessment of the efficacy of treatment and the detection of metastases at a subclinical stage. In 130 patients with a primary tumour and/or metastases, CT level was high. In 120 of them (92%), CEA level was also high. There was a positive correlation between levels of CT and of CEA, and both assays should be included in the preoperative examinations. Following removal of the tumour, normalisation of CEA levels takes several weeks, in contrast to CT where normalisation is rapid. Finally, these estimations may be used to detect familial forms at a subclinical stage. This enabled us to detect 16 new cases of MCT amongst 77 subjects studied.


[Acute renal failure due to non traumatic rhabdomyolysis. 11 cases (author's transl)].

Previous nuclear disease was found twice: Mc Ardle disease, dermatomyositis. Causative factors were: strenous exercise, hyperthermia, intoxication, influenza. Myalgias and/or myoedema was recorded in ten cases, associated with an hypovolemia of variable severity in eight. Oligo-anuria was observed in eight cases. The acute renal failure (ARF) was characterized by an increase in the serum creatinin more important than the rise in the blood urea and, in some cases, severe metabolic disturbances: hyperkaliema (6 cases), hypocalcemia (5 cases), hyperphosphatemia (5 cases) and hyperuricemia (5 cases). Diagnosis was made by the increase in sera of the muscles enzymes, specially the CPK and the search for myoglobinuria, positive during the first seven days. A complete recovery of renal function was observed in the nine survivors with a transient and moderate hypercalcemia in three. Three patients had persistant neuro-muscular deficiencies. Non traumatic rhabdomyolysis is not a rare cause of ARF and should be considered when the etiology of ARF is uncertain.


[A dominant form of pseudoachondroplastic dysplasia. A familial case (author's transl)].

The authors report a family of 5 subjects suffering from pseudoachondroplastic dysplasia in an autosomal dominant form. The interest of this report lies in the radiological documents obtained in the subjects at different ages (3, 18 and 63 years) and the extreme rarity of autosomal dominant forms since only six familial cases of this type have been described up to the present time.


[Hepatitis: the problem of terminology (author's transl)].

Every case of hepatitis must be defined as far as possible on the basis of four reference criteria: aetiological, clinical presentation, histological and course. Each criterion offers information concerning the classification, severity and course of the disease. The use of these criteria makes it possible to avoid all errors of interpretation and to avoid imprecise terminology, a typical example of which is "subacute hepatitis" which for some implies severe acute hepatitis running a prolonged course and for others the existence of confluent necrosis without it being possible to say whether this should be classified amongst cases of acute hepatitis or chronic hepatitis. The terms acute and chronic should retain their clinical significance, the term aggressive should retain a histological significance and, insofar as the piecemeal necrosis which characterises it is seen in both types of hepatitis, it should be dissociated, in terms of classification, from chronic hepatitis.


[Flat foot: treatment by sub-talar arthrodesis with reposition of the talus calcaneum (author's transl)].

Since 1962, the authors have used a technique of sub-talar arthrodesis combined with talar-calcaneal reposition ("horseman" operation) in cases of valgus flat foot, accompanied by symptoms, in moderate forms with exaggerated talar-calcaneal divergence and verticalisation of the talus. This operation involves only the sub-talar joint. The mid-tarsal joint is untouched. Technique must be precise in order to avoid hyper or hypo-correction. The results are constantly good. The mid-tarsal joint remains free, which offers a definite advantage in comparison with classical double tarsectomy.


Endocytosis in erythrocytes and their ghosts.

Study of endocytosis in human erythrocytes and their ghosts provides an opportunity for the elucidation of the steps involved in membrane invagination and fusion. The specific preparation being studied should be described with great care since circumstances that produce endocytosis may differ among the several available preparations. For example, in resealed red ghosts the addition of 0.5 to 1 mM Ca stimulates Mg-ATP-induced endocytosis, whereas in intact erythrocytes Ca addition stimulates primaquine-induced endocytosis and inhibits vinblastine-induced endocytosis. Furthermore, Ca inhibits endocytosis in white ghosts. EDTA can produce endocytosis in white ghosts but not in resealed red ghosts. In studies with white ghosts, incubation with EDTA, trypsin, or Mg-ATP produced endocytosis, whereas the prior addition of an antispectrin antibody prevented endocytosis. When the white ghost vacuoles were harvested they were found to be depleted of spectrin. These observations lead to the hypothesis that endocytic vacuoles are formed in areas of the membrane that have been substantially freed of spectrin.


The membrane abnormalities in paroxysmal nocturnal hemoglobinuria (PNH).

Paroxysmal nocturnal hemoglobinuria (PNH) cells are characterized by an abnormal membrane which interacts abnormally with normal serum complement. These abnormal reactions occur at two levels of the sequence: 1) All abnormal PNH cells fix more C3 than normal cells for a given activation of complement; 2) PNH III cells are more readily lysed by a given number of assembled terminal complexes. The nature of the lesion yielding these abnormal reactions is not known.


Hemolytic anemias associated with deficient or dysfunctional spectrin.

Elliptocytes from patients with hereditary elliptocytosis (HE) form elliptical ghosts and membrane skeletons. The composition of HE skeletons is quantitatively normal; however, in some but not all kindreds the major membrane skeletal protein, spectrin, is abnormally heat-sensitive, presumably due to a molecular defect which diminishes its conformational stability. Red cells from four mutants of the common house mouse (Mus musculus) with severe, recessive hemolytic anemias show marked membrane budding, fragmentation, and spherocytosis, which suggest membrane instability. Ghosts spontaneously vesiculate and are spectrin-deficient. The amount of spectrin varies from none to one-half the normal amount and correlates with the clinical severity of the four mutations. The cause of this deficiency remains to be determined. These mutants prove that spectrin is a critical determinant of membrane structural integrity and provide a unique opportunity to test, in intact red cells, putative functions of spectrin. Spectrin extracted from ghosts at low ionic strength is heterogeneous. At physiologic ionic strengths part (46 +/- 5%) is polymerized (P-spectrin) and complexed with actin, and part remains as nonpolymerized spectrin dimers and tetramers (NP-spectrin). We postulate that these are native membrane species which exist in a metabolically controlled equilibrium in vivo and that the proportion of these species regulates membrane shape, strength, and flexibility.


A model for the action of the anion exchange protein of the red blood cell.

Kinetic information on anion transport suggests that a mobile carrier system is involved in which the carrier-anion complex is able to spontaneously traverse the membrane. A second anion-binding site, the modifier, can when occupied reduce the rate of transport. Chemical studies with inhibitory probes suggest that the carrier and modifier sites are located in a specific transmembrane protein, band 3. The modifier site is accessible only from the internal surface but the carrier (transport) site is accessible from both the external and cytoplasmic surfaces. This information is discussed in terms of a model in which the anion traverses the membrane via a protein pathway. Transport involves conformational changes such that the transport site is alternately exposed to the external and cytoplasmic sides.


Erythrocyte disorders leading to potassium loss and cellular dehydration.

RBC K loss and cellular dehydration are associated with a variety of normal and abnormal erythrocyte conditions. In some cases (normal RBC aging, pyruvate-kinase-deficient RBCs and irreversibly sickled cells) cation and water changes are related to adenosine triphosphate (ATP) depletion and to increased RBC calcium content. In other disorders, such as hereditary xerocytosis, cation depletion and cellular hydration are not related to altered energy or calcium metabolism. Rather, this condition is thought to be due to a structural membrane defect which is manifested by imbalanced cation leaks (K less greater than Na gain) for which the active cation transport is unable to compensate. None of the disorders described here are associated with known structural membrane alterations. The fact that K loss and cellular dehydration are common to several RBC disorders suggests that this phenomenon may have a direct role in membrane injury. This hypothesis is supported by two separate observations: 1)Formation of irreversible sickled cells in vitro is prevented if K and water loss are inhibited, and these effects are independent of ATP depletion and calcium accumulation; 2) the mean critical hemolytic volume is markedly reduced in K- and water-depleted normal RBCs. RBC dehydration without intracellular cation depletion, however, is not associated with changes in mean critical hemolytic volume. These data thus indicate that K loss may have a direct role in RBC membrane injury. The mechanism by which this occurs and the associated alterations in membrane structure, however, remain to be identified.


Action of cobra venom phospholipase A2 toward lipids of erythrocyte membranes.

The activity of cobra venom phospholipase A2 toward phospholipids in erythrocyte membranes is enhanced significantly following ghosting of the membrane. The specificity observed is phosphatidylethanolamine greater than phosphatidylcholine and is the reverse of that expected from model studies with individual phospholipids. It is shown, utilizing phospholipid mixtures, that the activity and specificity of cobra venom phospholipase A2 is dependent on the presence of other lipids and their organization.


Psychotomimetics potentiate locomotor hyperactivity induced by dopaminergic drugs.

The spontaneous locomotor activity of rats was investigated in an open-field test. Apomorphine and d,1-amphetamine caused a dose dependent increase of locomotor activity. LSD, mescaline, and DMT in low doses were ineffective, when given alone, but caused a strong potentiation of the hypermotility induced by apomorphine and d,1-amphetamine. Cyproheptadine antagonized the potentiating effect of LSD without affecting the hypermotility induced by apomorphine, indicating a causal serotonergic involvement in the potentiation effect.


Postnatal alpha-methylphenylalanine treatment effects on adult mouse locomotor activity and avoidance learning.

Neonatal mice were injected for five days with a combination of alpha-methylphenylalanine and phenylalanine to determine the influences of excess phenylalanine during development upon the behavior of these mice as adults. Spontaneous activity, bolus production, passive avoidance learning, simple active avoidance learning and complex active avoidance learning were tested in mice treated at two different postnatal periods. The results show that the treatments during development produced adult behavioral alterations compared to controls. The effects were most pronounced in mice treated in the postnatal period immediately after birth. The behavioral effects can be summarized as increased emotionality and generalized, stimulus-induced activity as well as decreased passive avoidance performance and complex active avoidance performance. These behavioral deficits are consistent with those usually reported in various models of human phenylketonuria.


Modification of motor activity, passive avoidance conditioning and evoked potentials by microinjections of picrotoxin in both caudate nuclei in cats.

Inhibition of movements is the result of the caudate nucleus (CN) activity. This action seems to be necessary for passive avoidance conditioning (PAC). Much data indicates that GABA has inhibitory effects in the CN. The present report provides further evidence for GABA inhibition in th4 CN. In cats, the acquisition session of a PAC response was carried out following the bilateral administration of 6 microgram of picrotoxin or saline in the CN. Twenty four hours later (1st test session) the animals were placed in the security compartment and remained there during 600 sec. In the second test, the cats injected with picrotoxin crossed to the other compartment while the subjects injected with saline did not move. Another series of acute experiments were also carried out. Evoked potentials (EP) were recorded in the CN produced by nucleus centralis medialis electrical stimulation. After picrotoxin application the first and second peaks, which could represent EPSPs, incraeased while the third peak, which could represent IPSPs, decreased. In conclusion, it seems that GABAergic intracaudate transmission maintains a lower level of neuronal discharges and probably participates in the maintenance of a PAC but not in its acquisition.


Exploratory behaviour and aversive thresholds following intra-amygdaloid application of opiates in rats.

Rats were bilaterally implanted with guide cannulae aimed at the central or medial nucleus of the amygdala. Microinjections of morphine (10 microgram) at both sites significantly elevated the threshold of response in the flinch-jump test; but only at medial sites did naloxone (1 microgram) antagonise this effect. However, in the hole-board test, an opposite pattern of results emerged. Morphine injections into the central nucleus produced naloxone-reversible reductions in both exploration and activity whilst, in the medial nucleus, the morphine-induced decrease in exploration was not reversed by naloxone. It is concluded that (1) the presence or absence of naloxone-sensitive opiate receptors cannot always be deduced on the basis of a single behavioural test and (2) within the amygdaloid complex, two distinct naloxone-sensitive opiate systems appear to be involved in the modulation of behavioural responses to different forms of stimulation.


Nose-poking and head-dipping behaviors in rats prenatally exposed to alcohol.

In three experiments pregnant female rats consumed liquid diets containing various amounts of the total calories in the form of ethanol. In the first study, offspring of these females were tested in a nose-poking paradigm. The frequency of this response was found to be a direct function of the level of alcohol exposure in utero. In a second study when nose poking produced the onset of a dim light, animals prenatally exposed to alcohol were again found to poke more often, and this effect was not attenuated by preweanling handling. Finally, the generality of these findings became evident when head dipping rather than nose poking was examined; head-dip frequency was higher in alcohol-exposed offspring, and this effect was independent of stimulus complexity. Additionally, offspring body weights and survival rates following this prenatal alcohol exposure are presented.


Methadone depression of visual signal detection performance.

In order to determine the origin of a previously reported slowing of simple visual reaction time in subjects receiving single doses of oral methadone, three well-trained subjects performed. a modified double flash detection task several times after single doses of 5 mg and 10 mg of oral methadone and a placebo. A Theory of Signal Detectability analysis allowed for a clear distinction between drug-induced changes in visual sensitivity and changes in response bias. It was found that methadone reduced visual sensitivity. The peak depression in detection as well as the duration of the depressed performance were dose-related. Depression in performance paralleled the subjective effect of the drug in each subject. Averaged visual evoked potentials showed significant changes at peak drug effect to the onset of each of the pair of stimuli. It was concluded that methadone depresses visual function by acting on the visual parts of the central nervous system. The retina, midbrain and thalamic visual nuclei were discussed as possible sites of action of methadone.


Reinforcement with intragastric infusions of ethanol: blocking effect of FLA 57.

Suppression of oral intake of ethanol by FLA 57 has been reported for rats and was attributed to an inhibition of dopamine beta-hydroxylase. We have demonstrated the ability of FLA 57 (50 mg/kg, IP) to suppress bar-pressing for intragastric (IG) delivery of doses of ethanol (25 mg/kg). This indicates that the effect on oral intake of ethanol may not be attributed to a taste factor, e.g., a decreased palatability of the ethanol solution. The same dose of FLA 57 did not suppress responding for IG doses of sweet milk. Thus, there was not an impairment of appetitive behavior in general through some nonspecific depressant or toxic action. Furthermore, the primary reinforcing action of ethanol, when used to establish a buzzer as a conditioned reinforcer through repeated pairings, was blocked if FLA 57 was given before pairings. This was evidenced by a failure of such rats to bar-press above the baseline level in a later test of conditioned reinforcement, which contrasted with the increased responding seen for rats receiving saline instead of FLA 57 before ethanol. These data support the previous findings on oral ethanol and confirm that FLA 57 can impair the mechanism by which ethanol produces positive reinforcement in rats.


Destruction of dopaminergic nerve terminals in nucleus accumbens: effect on d-amphetamine self-administration.

Control rats initiate self-administration of d-amphetamine and achieve stable injection rates within 7-10 days. Rats in which dopamine nerve terminals in nucleus accumbens were destroyed by bilateral microinjections of 6-hydroxydopamine (6-OHDA) did not initiate self-administration of d-amphetamine when tested for as long as 19 days. In rats previously trained to self-administer d-amphetamine, 6-OHDA injections into nucleus accumbens abolished d-amphetamine self-administration. These results suggest that dopaminergic nerve terminals in nucleus accumbens are necessary for both the acquisition and maintenance of d-amphetamine self-administration.


Performance effects with repeated-response measures during pimozide-produced dopamine receptor blockade.

Rats were trained to lever-press for either food reward or brain-stimulation reward on a continuous reinforcement schedule. Following training each animal was extinguished (i.e. tested with the reward omitted) under the influence of pimozide (0.25 mg/Kg or 0.5 mg/Kg). Pimozide produced a dose-dependent reduction in the mean number of responses to extinction made by rats in ecach group. In a second experiment, pimozide produced a similar dose-dependent decrease in the performance of a naturally occurring behavior (nose-poking) that had never been associated with reward. These data suggest that dopamine receptor blockade can produce a perofrmance deficit in situations which require repetitive responses, and that this deficit is unrelated to the presence or absence of reward.


Properties of norepinephrine N-methyltransferase from pigeon brain.

Epinephrine concentration in pigeon hypothalamus was higher on an absolute basis and as a percentage of total catecholamine concentration that in other regions of pigeon brain or in rat hypothalamus. Norepinephrine N-methyltransferase (NMT; the epinephrine-forming enzyme) from pigeon brain had Km values for S-adenosyl-L-methionine and L-norepinephrine of 24 +/- 1 and 101 +/- 4 micrometer, respectively. The enzyme was inhibited by excess L-norepinephrine and by several arylakylamines that earlier had been identified as NMT inhibitors with the enzyme from mammalian brain and adrenal medulla. These results indicate that pigeon brain NMT is similar to that in mammalian brain and adrenal glands and can be inhibited by agents previously used to deplete brain epinephrine selectively in rats. The use of pigeons as experimental subjects in studies on the possible role of epinephrine-forming neurons in behavior is suggested.


Suppression of deprivation-induced food and water intake in rats and mice by naloxone.

Naloxone, an opiate antagonist, was administered to male and female rats and male mice after periods of food or water deprivation ranging from 12 to 48 hr. Naloxone (0.01-10 mg/kg) reduced postdeprivational water intake in most groups of rats and mice in a dose-related manner. Naloxone suppression of water consumption appeared to be independent of sexual differences in rats, and phase of the diurnal cycle, and length of the deprivation interval in both rats and mice. Postdeprivational food intake in male rats and mice was also reduced by naloxone in a dose-dependent fashion. This naloxone effect was less pronounced than actions observed with water intake, and tended to diminish with lengthening food deprivation periods. In general, mice appeared to be less sensitive than rats to naloxone suppression of food and water intake. Naloxone appears to markedly reduce appetitive behavior, particularly water intake, following deprivation in both rats and mice. The fact that low doses of naloxone can elicit these effects suggests that the drug is acting at specific tissue sites, possibly endorphine recpetors.


Autoradiographic comparison of neuronal and glial protein metabolism in rat hippocampus after food-motivated or footshock-motivated conditioning.

Quantitative autoradiography has shown that initial food-motivated conditioning results in an increase in 3H-phenylalanine incorporation into cytoplasmic proteins of rat hippocampal neurons. After 3 daily conditioning trials, the incorporation returned to an active control (pseudoconditioning) level while after 6 daily trials, the incorporation was decreased. No changes were revealed in the cells of hippocampal perineuronal glia. Four hours after a footshock-motivated passive avoidance trial, incorporation of 3H-phenylalanine was increased both in the neurons and in their perineuronal glia of rat hippocampus. By the time of a consolidation of this conditioning, such increase still remained perineuronal glia. An importance of the emotional background is outlined for a participation of glial cells in learning-induced metabolic changes in the nervous system.