Anti-inflammatory effects of blood platelets in the rat. A selective accumulation of blood platelets occurs at the sites of intradermal injection of zymosan and carrageenan in the rat. The inflammatory response to zymosan, assessed by the local accumulation of systemic radioactive human serum albumin, was significantly enhanced in platelet-depleted rats. Similar enhancements of the paw oedemas, caused by the subplantar injection of either carrageenan or zymosan, were also observed in thrombocytopenic animals. It is concluded that blood platelets may exert protective, i.e., anti-inflammatory, effects in some models of acute inflammation in the rat.


Medial hypertrophy in the small intestinal arteries in systemic hypertension, renal and essential. The arterioles and small arteries of the submucosa of the small intestine and the small arteries (vasa recta) of the mesentery have been measured histologically in cases of hypertension and in normotensive controls. Two methods of mensuration have been used: one employing direct measurement of internal calibre and thickness of media of vessels injected and fixed in a state of dilation at systolic pressure; the other employing measurement of the internal elastic lamina by curvimeter and the cross-sectional area of the media by planimeter in uninjected vessels, from which, by calculation, the internal calibre and medial thickness/lumen ratio of the vessel in an idealised state of dilatation to a perfect circle with uncrenated internal elastic lamina can be derived. These measurements show that the medial thickening observed in the hypertensive vessels is due to a true hypertrophy of the media rather than to a state of contracture. When cases of renal and of essential hypertension are compared the pattern of vascular change is seen to differ in the two conditions: while some degree of hypertrophy is present in both throughout the range of vessel sizes examined, it is more marked in renal than in essential hypertension in vessels with an internal radius of less than 100 micron; but in vessels of more than 100 micron radius the position is reversed. This difference in the reaction of the vessels presumably reflects a basic difference in the mechanisms of production of the two types of hypertension.


A new rationale for the management of large angle esotropia. It is not only possible but safe to exceed the traditional 5 mm maximum recession of each medial rectus muscle to correct large angle esotropia. It is possible to grade the amount of recession to the preoperative deviation, similar to that which is done for esotropia less than 35 prism diopters. The results of this series indicate that alignment to within 10 prism diopters with one procedure is more likely by large recessions of the medial rectus than by other approaches. If a reoperation is necessary, there still remain two other untouched horizontal muscles on which to operate.


Absence of the superior rectus muscle in Apert's syndrome. A patient with classical Apert's syndrome is discussed along with the finding of absent superior rectus muscle. This anomaly may be more common than thought, especially in relation to craniofacial anomalies. A review of Apert's syndrome and superior rectus agenesis is presented.


Congenital sclerocornea in Nigerian children. Four cases of congenital sclerocornea in Nigerian children are described. Two of these children are from the same family suggesting a genetical determination. A developmental anomaly with various manifestation and associated with other ocular abnormalities would appear to be the etiology. One of the cases also had extrophia vesicae, an association that has not been previously described.


Congenital hereditary bilateral nonattachment of retina: a sibship of two males. Two brothers, the only two children of nonconsanguineous parents, have no perception of light, bilateral microphthalmos, and degenerative corneal opacities that just allow observation of shallow anterior chambers and cataracts. The right eye of the older was removed at the age of 6 weeks: "congenital retinal detachment" was found. The birth of a subsequent affected son suggests that recessive genes are responsible. An X-linked gene is calculated to be more likely than autosomal recessive genes. These two males may suffer from a form of Norrie's disease without mental deficiency, however, they may be examples of the severest form of "falciform retinal folds" (autosomal recessive) or they may represent the same end-result from a different inherited pathological process. After the birth of the first affected child, the parents had been reassured that this undiagnosed, and at that time unknown condition, would not affect future children. The tragedy of a second affected child followed. We suggest that recessive genes (autosomal or X-linked) be specifically considered--with literature search--in any sporadic case of a bilateral symmetrical condition of the eyes not hitherto well known, especially if congenital, and in the absence of consanguinity of parents affected males in previous maternal generations. The possibility of a dominant mutation when a single case occurs in a sibship should also be considered.


Evolution of Leber's miliary aneurysms: a clinicopathological study. The clinical course is described of two genuine cases of the disease of Leber's miliary aneurysms that developed into Coats' disease. Following the issue of the disease in a painful and blind eye, the cases were examined histopathologically. In the first case the transformation into Coats' disease, and subsequently into a painful eye, took six years, in the second case four years. This histopathological examination revealed vascular formations of the superficial corneal stroma of the periphery in the second case. In respect of the retina the presence of neovascularization was observed. Pathological vessels of varying width were also found in the deeper retinal layers. The presence of cholesterol clefts should be regarded rather as a consequence of the chronicity of the case than as being a characteristic feature of the condition.


Mobius syndrome and Poland anomaly: case report and review of the literature. A 6-year-old boy had the combination of Mobius Syndrome and the Poland anomaly. Although rare, this association is repeatedly encountered. The absence of the pectoral muscle in the Poland anomaly supports the theory that in both conditions the muscular and skeletal abnormalities are due to a common fetal mesodermal defect.


A funny thing happened to us on the way to the latent entities. Inferred latent entities, whether those of psychoanalysis, factor analysis, or cluster analysis, have declined in value for many clinical psychologists, both as tools of practice and as objects of theoretical interest. Behavior modification, rational-emotive therapy, crisis intervention, psycho-pharmacology, and actuarial prediction all tend to minimize reliance on latent entities in favor of purely dispositional concepts. Behavior genetics is, however, a powerful movement to the contrary. As regards categorical entities (types, taxa, syndromes, diseases), history reveals no impressive examples of their discovery by cluster algorithms; whereas organic medicine and psychopathology have both discovered many taxonic entities without reliance on formal (statistical) cluster methods. I offer eight reasons for this strange condition, with associated suggestions for ameliorating it. Adopting a realist instead of a fictionist approach to taxonomy, I give high priority to theory-based mathematical derivation of quantitative consistency tests for all taxometric results. I urge a large scale cooperative survey of taxometric methods based on Monte Carlo runs, biological pseudoproblems where the true axon is independently known, and live problem in genetics, organic medicine, and psychopathology. An empirical example of taxometric bootstrapping and consistency testing was presented from my own current research on schizotypy.


Hydrocephalus combined with congenital cataract and microphthalmia. We describe a case of bilateral microphthalmia with bilateral congenital cataracts associated with hydrocephalus in a 9-month-old girl with consanguineous parents. The differential diagnosis included: (1) congenital rubella syndrome; (2) congenital toxoplasmosis; (3) chromosome alterations; and (4) metabolic disease. However, negative clinical, laboratory, and instrumental investigations excluded all of these hypotheses. We stress the usefulness of echography in establishing whether or not infection has occurred during intrauterine life.


The visual results following infantile glaucoma surgery. The visual function of 26 patients with a diagnosis of primary infantile glaucoma was studied. Quantitative visual acuities were determined in 15 patients. Sixteen eyes in these patients achieved 20/20 to 20/50 visual acuity and five additional eyes had 20/60 to 20/200. Thirteen eyes in young patients were noted to have central and steady fixation and four eyes exhibited eccentric fixation. Seven eyes were considered to have decreased visual acuity on the basis of anatomical defects. The remainder of the patients had decreased visual acuities secondary to amblyopia or large refractive errors. Amblyopia responded to treatment in six of 12 patients.


Psychological tests and borderline patients. Psychological tests of 32 borderline or nonborderline (psychotic) patients were compared with the structural diagnoses arrived at on the basis of two kinds of clinical-research interviews: The DIB (following Gunderson's criteria) and the structural interview (following Kernberg's criteria). Test results were reported in terms of the diagnosis based on the full test battery, as well as in terms of the structural diagnosis implied by the presence or absence of thinking disturbances on the (structured) WAIS as compared with the (unstructured) Rorschach test. Statistically significant agreement was shown among these four approaches.


Rorschach Developmental Level in the offspring of patients with schizophrenia and manic-depressive illness. The Developmental Level (DL) score was assessed from Rorschach inkblot tests of 305 children. Children were either the offspring of one schizophrenic, one manic-depressive, one physically ill, or of two normal parents. Socioeconomic status, age, and intelligence were treated as covariates. Children of one schizophrenic parent had lower DL scores than children in the other three groups.


Eyelid involvement as the presenting manifestation of discoid lupus erythematosus. A case with discoid lupus erythematosus was diagnosed by a palpebral lesion as the initial manifestation of her disease. Lid skin biopsy confirmed the diagnosis. Awareness to such unusual localization of discoid lupus erythematosus can lead to an early discovery of the skin disease.


Effects of maternal themes upon death imagery. Two samples (n = 47, n = 45) of women were studied to determine the impact of maternal messages upon death imagery as measured by the Holtzmann Inkblots. In both samples a maternal symbiotic message significantly decreased death imagery. A maternal monosymbiotic message resulted in decreased death imagery in only one sample. Control messages produced no changes in death imagery. The findings are congruent with theories that link death anxiety with concern about separation from parental figures.


A validity scale sign calling for caution in the interpretation of MMPIs among psychiatric inpatients. Three expert MMPI judges classified 100 psychiatric inpatients as psychotic or non-psychotic on the basis of their MMPIs. Validity scale data, as well as clinical scale scores, were included for 50 of the profiles, while the validity scale scores were withheld from the judges for the remaining 50 profiles. Within each of the above two groups, half had a "positive" validity scale sign (a defensive validity scale configuration defined as L or K greater than or equal to 70, or both greater than or equal to 60) and half had a negative validity scale sign, indicating a lack of defensiveness. Using actual diagnosis as the external criterion, results indicated that the majority of defensive psychotic patients produced clinical scale configurations which appeared nonpsychotic to the judges. Conversely, the majority of nondefensive nonpsychotics produced psychotic-appearing clinical scale configurations. These two types of test misses suggest that K corrections on MMPI scales relating to psychosis are not optimal for psychiatric inpatients. Guidelines were developed for interpreting defensive profiles.


Ambulatory pediatric ophthalmic surgery. A retrospective analysis of 100 consecutive cases of ambulatory pediatric ophthalmic surgery was performed. The diagnoses included strabismus surgery, nasolacrimal duct probing, and excision of chalazion. The hospital stay was extended in only two cases and that was due to vomiting. This is a known side effect of halothane anesthesia and falls well within the known incidence of this occurrence. Ambulatory surgery appears to be a very viable method for short-stay surgery in children.


The Tennessee Self-Concept Scale and the normal personality sphere (16PF). An examination of the internal structure of the Tennessee Self-Concept Scale (TSCS) and the interrelationship among the TSCS scales and the secondary dimensions of the Sixteen Personality Factor Questionnaire (16PF) supported three conclusions: (a) The primary dimension underlying the TSCS is positive self-evaluation, freedom from neurotic symptoms, or the absence of anxiety, (b) this central dimension of the TSCS aligns with the 16PF secondary Anxiety vs. Adjustment, and is virtually independent of the other dimensions of the normal personality sphere, and (c) the mutual orthogonality of extraversion, anxiety or neuroticism, and an empirically derived psychoticism scale provided some support for Eysenck's PEN theory of personality organization.


Relationships between locus of control and anxiety. Reviews findings on the relationships between locus of control and anxiety and examines these relationships for three types of anxiety measures; general trait anxiety, situation specific trait anxiety, and state anxiety. In general, findings support the existence of meaningful relationships between greater externality and higher levels of both general trait anxiety and test anxiety. It was suggested that the relation between locus of control and state anxiety is a function of the situational context in which state anxiety is measured.


Some psychological correlates of hemophilia. Personality characteristics, as measured by the Personality Research Form (PRF-E) and a specially designed questionnaire, of 33 male hemophiliacs were investigated. Subjects were subdivided into three separate categories, bases on the severity of their clinical manifestations of the disease. Results showed that, as a whole, all scored within plus or minus one standard deviation of the mean on all PRF-E scales. When the data were analyzed according to severity level, however, a significant difference appeared among the groups on the Harmavoidance scale, which indicated that those suffering from the most severe form of the disease were the least likely to avoid potentially hazardous activities. These findings and those from the questionnaire were discussed. It was suggested that when the disease is quite severe subjects may abandon attempts to seek and control life-style antecedents of the occurrence of bleeding episodes.


Irrational beliefs and psychological needs. Studied the relationship between irrational beliefs and 15 psychological needs described by Murray. The Irrational Beliefs Test (IBT) and the Adjective Check List (ACL) were administered to 46 high school students and 50 adults. Results of stepwise multiple regression analyses indicated that five IBT scales and IBT Full-Scale were significantly associated with psychological needs. It was concluded that pathological behavior could not be readily predicted on the basis of irrational beliefs. It was further concluded that Ellis' model of personality obtained additional validating evidence.


Learned helplessness and learned effectiveness: effects of explicit response cues on individuals differing in personal control expectancies. Female undergraduates (n = 62) who scored as extreme internals or externals on the Mirels Personal Fate Control Scale participated in a partial replication of Hiroto's learned helplessness experiment. Lights were added to the treatment apparatus, which made explicit to subjects the contingency or noncontingency between their responses and the termination of an aversive tone. As predicted, the performance of internals was significantly impaired by uncontrollability (learned helplessness), while that of externals was facilitated by controllability (learned effectiveness). Externals performed as well as internals in the "escapable" condition, but their performance was inferior to that of internals in the control condition. Following "inescapable" treatment, internals performed worse than externals. These results are supportive of Lefcourt's theory of cue explication. Implications for locus of control and learned helplessness research are discussed.


Environmental determinants of memory improvement in late adulthood. Two studies were conducted with nursing home residents to determine whether memory could be improved. This was accomplished by increasing the cognitive demand of the environment and then varying the extent to which residents were motivated to attend to and remember these environmental factors. In Study 1, motivation to practice recommended cognitive activities was manipulated by varying the degree of reciprocal self-disclosure offered by interviewers in a series of dyadic interactions. In Study 2, motivation to practice recommended cognitive activities was manipulated by varying whether positive outcomes were contingent on attending to and remembering these activities, which increased in demand over time. Whether as a function of interpersonal (Study 1) or practical (Study 2) incentives, engaging in cognitive activity resulted in improvement on standard short-term memory tests, including probe recall and pattern recall, as well as in improvement on nurses' ratings of alertness, mental activity, and social adjustment for experimental groups relative to controls.


When practice makes imperfect: debilitating effects of overlearning. It was hypothesized that as overlearning leads to "mindlessness," the individual components of a task become relatively inaccessible to consciousness and therefore unavailable to serve as evidence of task competence. This may lead to a decrement in performance if circumstances, for example, a label connoting relative inferiority, lead one to question one's ability. This was tested in the first experiment by varying practice on a task (no practice, moderate practice, and overpractice) by label assigned to subjects (no label, assistant, boss). As predicted, performance decrements resulted for the no practice and overpracticed subjects who were assigned the inferior status label but not for the moderate practice subjects for whom the task components were still salient. In a second experiment it was found that the debilitation could be prevented for an overlearned task by making components of the task salient. Implications for the vulnerability of experts to these performance debilitations are explored.


The effect of situational contingencies on female retaliative behavior. Most studies that have found sex differences in aggression have reported that males are more aggressive than females. Recent evidence, however, suggests that the expectation of female nonaggressiveness may be unwarranted. The present study attempted to reconcile these differences by considering the contingencies of female aggression. Thirty females competed in a task designed to measure aggression (a) alone, (b) in the presence of a silent observer, or (c) in the presence of a supportive observer. Results indicated that as provocation increased, women in the private condition responded more aggressively than did women in the public condition. Also, women who responded in the presence of an audience were more aggressive when the observer was supportive than when she was silent. It is concluded that the usual findings of female nonaggressiveness may be attributable to women's expectations of disapproval for aggressive behavior.


Emotion recognition: the role of facial movement and the relative importance of upper and lower areas of the face. In order to investigate the role of facial movement in the recognition of emotions, faces were covered with black makeup and white spots. Video recordings of such faces were played back so that only the white spots were visible. The results demonstrated that moving displays of happiness, sadness, fear, surprise, anger and disgust were recognized more accurately than static displays of the white spots at the apex of the expressions. This indicated that facial motion, in the absence of information about the shape and position of facial features, is informative about these basic emotions. Normally illuminated dynamic displays of these expressions, however, were recognized more accurately than displays of moving spots. The relative effectiveness of upper and lower facial areas for the recognition of these six emotions was also investigated using normally illuminated and spots-only displays. In both instances the results indicated that different facial regions are more informative for different emitions. The movement patterns characterizing the various emotional expressions as well as common confusions between emotions are also discussed.


Allocation of attention and the Type A coronary-prone behavior pattern. Three studies were conducted to assess the attentional style of individuals with the Type A coronary-prone behavior pattern. Experiment 1, which made use of a dual-task paradigm, revealed that Type A's focus their attention on central tasks; thus, they attend less to peripheral tasks than do Type B's. Experiments 2 and 3, which used a single task performed in the presence of a distracting stimulus, indicated that Type A's actively inhibit or suppress their attention to task-irrelevant peripheral events that might distract them from task performance. These findings validated anecdotal observations that Type A's appear hyperalert (focused in their attention) but neglect task-irrelevant cues. Previous research has demonstrated that Type A's fail to report fatigue as well as a variety of other physical symptoms of illness during task performance. To the extent that symptoms are analogous to peripheral events that distract from task performance, the data suggest that Type A's suppress their attention to symptoms. Implications of the attentional style of Type A's for the pathogenesis of coronary artery and heart disease are discussed.


Sex differences in bystander intervention in a theft. A series of studies demonstrated a strong relationship among the situation-defining variable of degree of harm to victim, sexual configuration among participants, and bystanders' willingness to intervene to stop a theft. A pretest showed that a prior verbal commitment was absolutely necessary for intervention. The remaining data showed that high harm to a victim produced a high rate of intervention and showed strong sex differences in helping behavior in low-harm conditions. A high percentage of female bystanders helped in both low- and high-harm situations, whereas frequent helping by males was observed only when harm to the victim was high. Female victims elicited a significantly greater amount of helping, and sex of thief had no effect. A significant sex of bystander, sex of victim, and harm to victim interaction best describes the data. Results are interpreted in terms of different motivational sets held by males and females when they are responsible for the fate of others. Results also support the utility of an interactionist approach to the question of how individual and situational variables influence prosocial action.


Metabolic, respiratory, vasomotor and body temperature responses to beta-endorphin and morphine in rabbits. 1. The effects of beta-endorphin and morphine on thermoregulatory responses of unanaesthetized rabbits to different ambient temperatures (Ta) of 2, 22 and 32 degrees C were assessed. 2. Intraventricular administration of either beta-endorphin or morphine produced dose-dependent hypothermia at 2 and 22 degrees C Ta. At 2 degrees C Ta the hypothermia was brought about solely by a decrease in metabolic heat production. At 22 degrees C Ta the hypothermia was due to a decrease in metabolism and an increase in peripheral blood flow. However, at 32 degrees C Ta, there were no changes in rectal temperature in response to either beta-endorphin or morphine application. 3. Hypothermic effects of the administration of beta-endorphin or morphine were greatly antagonized by pretreatment of animals with either an opiate antagonist naloxone or a serotonin depletor 5,6-dihydroxytryptamine. 4. These findings indicate that the hypothermic responses to beta-endorphin or morphine in rabbits may be mediated through central serotonergic mechanisms. The hypothermia was due to a decrease in heat production and/or an increase in heat loss.


Microvascular filling pattern in rat liver sinusoids during vagal stimulation. 1. The terminal microcirculation in the transilluminated ventral margin of the rat liver was observed and recorded by a video-microscope system. The volumetric flow rate in a liver sinusoid was calculated from the observed diameter of the sinusoid and the intra-sinusoid erythrocyte flow velocity. 2. The topographic distribution of liver sinusoids within an arbitrary boundary of a microscopic field of terminal liver microcirculation was observed and the total inflow and outflow in the field were determined. 3. Both vagus nerves at the lower end of the oesophagus were stimulated at supramaximal voltage. Vagal stimulation dilated the calibre of liver sinusoids and paradoxically diminished the erythrocyte flow velocity in each individual liver sinusoid, but the total volumetric flows in a microscopic field remained unchanged. 4. Vagal stimulation also increased the number of liver sinusoids in a microscopic field by opening previously closed liver sinusoids. This recruitment contributed two-thirds of the total increase of the sinusoidal capacity while the other one third was the result of distension of existing liver sinusoids.


The effect of stimulation by meat on gastrins in pyloric antral mucosa of anaesthetized cats. Chloralose anaesthetized cats were prepared with fundic and antral pouches. After stimulation with meat extract suspension in the antral pouches, the antral mucosae were collected, homogenized and subjected to subcellular fractionation to produce whole homogenates, debris, mitochondrial, granule and microsomal fractions and the cell supernatant. Total gastrin concentration and the quantities of gastrin components were measured in these cell fractions and compared with values obtained from a group of control animals which were not stimulated. Stimulation significantly increased the concentration of total gastrin in whole homogenates and in the cell supernatant. In whole homogenates the concentrations of gastrin components I, II, III and void volume gastrin all increased significantly after stimulation. In granules the concentration of Component III significantly increased. In microsomes the concentration of Componenet IV increased significantly. In cell supernatant the total amounts of Components III and IV increased significantly. It is concluded there was synthesis of gastrin under the experimental conditions used. The concentrations of those gastrin components which are larger than the predominant storage form (Component III) are increased and these larger components may be biosynthetic precursors. The significant increase in Component IV concentration in the cell supernatant and microsomes may suggest that Component IV is formed at least in part by antral tissue as well as by the known conversion process which occurs in cat blood.


Reflex pathways in the abdominal prevertebral ganglia: evidence for a colo-colonic inhibitory reflex. 1. In vitro experiments were performed on preparations consisting of prevertebral ganglia attached to the entire colon of guinea-pigs. The colon was divided into an orad and a caudad segment and intraluminal pressure was recorded from the terminal end of each segment. Intracellular recordings were simultaneously obtained from neurones in the coeliac plexus. 2. The source of mechanosensory input from the colon paralleled the responses to mesenteric nerve stimulation. That is, section of the mesenteric nerve that contributed the strongest synaptic input to a neurone eliminated most of the mechanosensory input to that neurone. 3. The origin of the mechanosensory input to some neurones could be localized as coming from either the orad or caudad segment of the colon. In the coeliac ganglia 68% of the neurones tested responded primarily to orad distension and 37% to caudad distension. In the superior mesenteric ganglion 57% responded to orad distension and 43% to caudad distension. 4. Repetitive stimulation of the mesenteric nerve trunks arising from the prevertebral ganglia inhibited contractions differentially in the orad and caudad segments. The inferior coeliac nerves inhibited primarily the orad segments of colon and the lumbar colonic nerves inhibited primarily the caudad segments of colon. Stimulation of the superior coeliac nerves did not alter the motility of either segment. 5. When one of the colonic segments was distended, contractions in the other colonic segment were inhibited in 71% of the distensions. This inhibition operated in both directions: either orad inhibiting caudad or vice versa. 6. Cutting the intermesenteric nerve which communicates between the orad and caudad prevertebral ganglia eliminated the inhibitory reflex. 7. These experiments provide evidence for a colo-colonic inhibitory reflex mediated through pathways in the prevertebral ganglia.


Role of gastric antrum in gastric and intestinal phases of gastric secretion in dogs. 1. The gastric and intestinal phases of gastric secretions were selectively evoked before and after the removal of the antral mucosa in four dogs provided with a special cannula that allowed complete separation of the stomach and duodenum without interrupting neural connexions between them. 2. The gastric phase induced by 5% liver extract meal administered into the stomach at various distension pressures (ranging from 0 to 15cm H2O) resulted in an increase in acid output to about 56% of the histamine maximum and in a marked rise in serum gastrin. 3. Following resection of the antral mucosa, the gastric acid response to meal of liver extract was reduced by about 50% and serum gastrin response was completely eliminated. Exogenous gastrin (G-17) given during the gastric phase induced by such a meal in dogs with antral mucosectomy failed to restore acid output to pre-resection level. 4. Intestinal perfusion of meal of liver extract in graded amounts stimulated gastric acid secretion to about 30% of histamine maximum acid output and raised significantly serum gastrin level. 5. Antral mucosectomy abolished almost completely both gastric acid and serum gastrin response to intestinal meal of liver extract. 6. Exogenous gastrin given during the intestinal meal of liver extract failed to restore acid output to the pre-resection level, suggesting that this procedure greatly reduced the secretory capacity of the oxyntic glands. 7. We conclude that the antral gland area plays an important role in the gastric phase and that it is  a prerequisite for the intestinal phase of gastric secretion.


The properties of bovine lens membranes measured by a conventional double-chamber method. 1. When the bovine lens was mounted in a divided chamber, an asymmetry potential of 4.3 mV (anterior face positive) was measured across the lens and values of 0.48 and 0.60 were obtained for P(Na)/P(K) of the anterior and posterior faces respectively.2. The half-times for the depolarization of the anterior and posterior face potentials on increasing the external K concentration were 20 and 14 min respectively compared to less than 2 min for the corresponding change determined previously from the totally immersed lens.3. The electrical resistance of the anterior surface was significantly smaller than that of the posterior and both resistances were much smaller than the value previously obtained from the bovine lens immersed in solution.4. The K permeability of the anterior surface, measured by (42)K efflux experiments, was greater than the value for the posterior surface and both were again very much higher than the value obtained for the totally immersed lens.5. The discrepancies between the present double-chamber preparation and the data obtained previously can be explained if it is assumed that the capsule provides a short-circuit pathway between the chamber port and the lens membranes. As the capsule is thicker at the anterior face, the short circuit there would be greater and this may explain many previously observed ;asymmetry' properties for the lens.


The responses of Golgi tendon organs to stimulation of different combinations of motor units. 1. Afferent discharges were recorded from stretch receptors identified as Golgi tendon organs, in the medial gastrocnemius and soleus muscles of the cat. 2. The response of a tendon organ was recorded during stimulation of one or more motor units selected for the intensity of discharge elicited from the receptor during twitch and tetanic contractions. 3. Repetitive stimulation of a single motor unit could evoke in a tendon organ a firing rate of up to 174 impulses/sec. The mean rate for a total of 90 motor units was 65 (+/- 32 S.D.) impulses/sec. No significant difference in effectiveness could be detected between motor units covering a wide range of contraction speeds, tetanic tensions and susceptibility to fatigue. 4. The response of a tendon organ to contraction of several motor units in combination was greater than from stimulating any one motor unit alone but less than predicted from the algebraic sum of individual responses. 5. The relation between firing rate and tension was plotted for combined stimulation of up to ten motor units. The relation was found to be a straight line provided the size of the response elicited by each motor unit in the stimulated bundle was similar or when responses were ranked according to their intensity. When one motor unit evoked a much more powerful response than others it tended to dominate the discharge and disturb the linearity. 6. Evidence is provided that the sites of stimulus transduction for motor units which exert their effect directly on the receptor can be relatively independent of one another. It is argued that on such occasions summation of responses may be attributed to mechanisms operating at the level of impulse generation.


Influence of sex and age on febrile responses to peripheral and central administration of pyrogens in the rabbit. 1. Intravenous injections of leucocytic pyrogen in doses of 15, 30 and 60 mul./kg caused febrile reactions in male rabbits that were related to age of the animal: rabbits under 2 yr of age developed fevers that were related to dose of pyrogen, while rabbits 2-3 yr old showed large febrile responses which were not dose-related.2. Female rabbits of comparable ages generally showed smaller febrile reactions to I.V. leucocytic pyrogen, and still older females (3-5 yr) developed fever only after the largest dose.3. Dose-related febrile responses to 2.5, 5 and 10 mul. leucocytic pyrogen given intracerebroventricularly (I.C.V.) were greater in male rabbits 1-3 yr old than in females of comparable age. Female rabbits 3-5 yr old showed dose-related fevers that were smaller than those of younger animals of both sexes.4. There were no major differences in response to 125, 250 and 500 ng PGE(2), given I.C.V., between male and female rabbits under 2 yr of age. Females 2-3 yr of age had greater responses to PGE(2) than males of comparable age whilst the oldest females showed smaller responses.5. It is concluded that the febrile response of the rabbit to peripheral and central leucocytic pyrogen varies with both age and sex. Differences in sensitivity of central fever controls to endogenous pyrogen in animals of different ages and sexes may account for the different responses to peripheral pyrogen.


Ionic basis for electrical properties of tonic fibres in rat extraocular muscles. 1. The ionic conductances underlying some of the electrophysiological properties of multiply innervated or tonic fibres of rat extraocular muscles were examined in vitro with double-barrelled micro-electrodes.2. Exposure of the muscle to a Cl-free saline did not change the effective resistance (R(eff)) of tonic fibres which was 5.14 +/- 0.45 MOmega (n = 7) in control saline and 4.78 +/- 0.45 MOmega (n = 12) in Cl-free saline (P > 0.1). In contrast, in singly innervated or twitch fibres Cl removal increased R(eff) from 1.77 +/- 0.21 MOmega (n = 19) to 2.69 +/- 0.12 MOmega (n = 22) (P < 0.001).3. Tonic fibres with membrane potentials restored to - 80 mV by injecting current responded to intracellular depolarizing pulses with a brief, slow response (slow peak potential) which added to the rising phase of the electrotonic potential. The slow peak potential began at a membrane potential of - 40 to - 35 mV and was graded. Increasing depolarizations evoked faster and larger responses which did not over-shoot the zero level of membrane potential.4. The slow peak potential was not blocked by 10 muM-D-600 hydrochloride but was markedly reduced by the absence of Na and by 10 muM-tetrodotoxin. The response was broadened about five times by 25 mM-tetraethylammonium.5. Raising bath temperature from 21-25 degrees C to 37 degrees C reversibly depressed and shortened the slow peak potential but did not transform it into an action potential.6. It is concluded that the characteristic high R(eff) of tonic fibres results from a lack of a membrane conductance to Cl and that the slow peak potential involves the transient activation of Na and K channels which are pharmacologically similar to the respective channels of twitch fibres.


Differential conduction block in branches of a bifurcating axon. 1. Propagation of action potentials at high frequency was studied in a branching axon of the lobster by means of simultaneous intracellular recording both before and after the branch point. 2. Although the branching axon studied has a geometrical ratio close to one (perfect impedance matching) conduction across the branch point failed at stimulation frequencies above 30 Hz. 3. The block of conduction after high frequency stimulation occurred at the branch point per se. The parent axon and daughter branches continued to conduct action potentials. 4. Conduction block after high frequency stimulation appeared first in the thicker daughter branch and only later in the thin branch. 5. With high frequency stimulation there was a 10-15% reduction in amplitude of the action potential in the parent axon, a corresponding decrease in the rate of rise of the action potential, a 25-30% decrease in conduction velocity, marked increase in threshold and prolongation of the refractory period. In addition the membrane was depolarized by 1-3 mV. 6. Measurements of the membrane current using the patch clamp technique showed a large decrease in the phase of inward current associated with the action potential, before the branching point. 7. The small membrane depolarization seen after high frequency stimulation is not the sole cause of the conduction block. Imposed prolonged membrane depolarization (8 mV for 120 sec) was insufficient to produce conduction block. 8. In vivo chronic extracellular recordings from the main nerve bundle (which contains the parent axon) and the large daughter branch revealed that: (a) the duration and frequency of trains of action potentials along the axons exceeded those used in the isolated nerve experiments and (b) conduction failure in the large daughter branch could be induced in the whole animal by electrical stimulation of the main branch as in the isolated preparation. 9. Possible mechanisms underlying block of conduction after high frequency stimulation in a branching axon are discussed.


Mechanisms involved in differential conduction of potentials at high frequency in a branching axon. 1. The ionic mechanisms involved in block of conduction of action potentials following high frequency stimulation were studied in a branching axon of the lobster Panulirus penicillatus. 2. A 2-3 mM increase in extracellular K concentration (normal concentration 12 mM) produced block of conduction into both daughter branches. 3. While conduction block induced by high frequency stimulation occurs first into the large daughter branch and only later into the smaller one, propagation into both branches is blocked simultaneously by increased extracellular K concentration. 4. Increasing extracellular K by 2-3 mM resulted in membrane depolarization, reduction in membrane resistance and reduced excitability. The latter two effects were larger than expected from the small depolarization. It appears that increase of extracellular K has direct effects on membrane excitability. 5. It is suggested that block of conduction after high frequency stimulation results from accumulation of K in the extracellular space. However, in order to account for differential conduction block in the two branches one must assume differential buildup of extracellular K concentration around the two branches during high frequency stimulation. 6. Ultrastructural studies using La and horseradish peroxidase as extracellular markers show that the space around the two branches is similar and is open to the extracellular space. Therefore differences in periaxonal volume cannot account for differential buildup of K around the two branches. 7. It is demonstrated that the lobster axon has a Na+/K+ electrogenic pump. After blocking this pump with ouabain, stimulation at high frequency resulted in a conduction block in the two branches almost at the same time. 8. Injection of Ca2+ intracellularly into the thick branch prevents or delays the appearance of conduction block after high frequency stimulation. 9. A mechanism based on these findings is suggested to explain the differential conduction block seen after high frequency stimulation in a branching axon with almost ideal impedance matching.


A mathematical model for conduction of action potentials along bifurcating axons. 1. A mathematical model based on the Hodgkin-Huxley equations is derived to describe quantitatively the propagation of action potentials in a branching axon. 2. The model treats the case of a bifurcating axon with branches of different diameters. The solution takes into account the changes in space constant in the different regions. 3. The model allows for investigating parameters leading to preferential conduction of action potentials in one daughter branch as seen experimentally. 4. Assuming that the only difference between the various daughter branches is in their diameters, conduction blocks should occur simultaneously rather than differentially into all daughter branches when the geometrical ratio is greater than 10. 5. In order to obtain differential conduction into the two branches changes in ionic concentrations due to the repetitive action potentials had to be introduced into the equations. 6. We find that conditions which allow differential buildup of K concentration around the two branches, produce differential conduction block. These conditions may be different periaxonal spaces around the branches or different time constant for recovery processes that eliminate K from the periaxonal space. 7. The effects of an inexcitable branch on conduction of action potentials in the second branch are described. 8. We find that the membrane current which is associated with the action potential is much more sensitive than the action potential itself and shows more distinct changes near regions of inhomogeneity such as a branch point, a step increase in diameter or an inexcitable branch.


Evidence supporting a role for endogenous vasopressin in natural suppression of fever in the sheep. 1. The antipyretic effect of arginine vasopressin (AVP) introduced into the brain by push-pull perfusion was investigated in the sheep. 2. Control perfusions with sucrose solutions had no effect on fevers induced by a bacterial endotoxin. Sucrose solutions containing AVP (4.0 microgram/ml.) perfused at 40 microliter./min had significant antipyretic activity, reducing the two peaks of the fever but had no effect on resting body temperature. 3. Loci in which AVP induced antipyresis were limited to the septal region about 2-3 mm anterior to the anterior commissure. 4. The amounts of AVP in perfusates from the septal region correlated negatively with changes in body temperature. 5. AVP administered I.V. did not lower fever. 6. AVP plasma levels correlated negatively with fever magnitude following premature birth induced by dexamethasone.


Rabbit diaphragm: two types of fibres determined by calcium strontium activation and protein content. 1. Submaximum Ca2+- and Sr2+-activated tensions were measured in functionally skinned fibres from the rabbit diaphragm. 2. The fibres could be classified into two types on the basis of activation by divalent cations. Type S fibres required a slightly higher [Ca2+] than [Sr2+] for half-maximal activation of tension. Type F fibres required 2 times higher [Ca2+] than type S and 8.5 times higher [Sr2+]. 3. Sodium dodecyl sulphate disc gels of type F fibres showed protein band patterns similar to those of fast-twitch muscle; those of type S fibres were identical to those of slow-twitch fibres. 4. Sodium dodecyl sulphate disk gels of mixed, non-classified diaphragm fibres and an actual count of randomly selected fibres classified by Ca2+/Sr2+ tension characteristics showed the diaphragm to be composed of 60% fast-twitch fibres and 40% slow-twitch fibres. 5. The protein stoichiometries of the two fibre types are consonant with the accepted stoichiometries for skeletal muscle. 6. The percentages of type F and type S fibres in the diaphragm suggest that high adenosine-triphosphatase activity shown by histochemical techniques (Davies & Gunn, 1972) is associated with the type F fibres, and low activity with the type S fibres.


Protein deprivation: its effects on fever and plasma iron during bacterial infection in rabbits. 1. The effects of chronic dietary protein deprivation on fever and host plasma iron reduction in bacterially infected rabbits (Oryctolagus cuniculus) were investigated. 2. Injection with Pasteurella multocida, a Gram-negative bacterium pathogenic to rabbits, led to an attenuated 24 hr fever in the protein-deprived rabbits (0.26 degrees C) compared with the 24 hr fever in the control rabbits (1.43 degrees C). 3. Plasma iron concentration remained relatively high in the protein-deprived rabbits as measured 24 hr after injection with bacteria. Total iron binding capacity did not change in the protein-deprived rabbits as measured 24 hr after injection with bacteria. 4. Inoculation of the rabbits with endogenous pyrogen from donor rabbits resulted in fever and reduction in plasma iron concentration that was of equal magnitude in the protein-deprived and control rabbits. 5. There were no differences in the concentration of total circulating leukocytes or in the differential count between the protein-deprived and control rabbits before and 24 hr after injection with bacteria. 6. These data support the hypothesis that chronic protein deprivation in rabbits results in a diminished synthesis or release, or both, of endogenous pyrogen from circulating leukocytic phagocytes, resulting in an attenuated fever and a relative hyperferremia during infection.


The metabolic effects of sodium depletion in calves on salt appetite assessed by operant methods. 1. Sodium deficiency was induced in calves by unilateral exteriorization of the parotid duct, the continual loss of alkaline saliva from the body to the environment causing negative sodium balance. 2. The metabolic effect of negative sodium balance was seen in statistically significant reduction in plasma sodium and blood bicarbonate, together with marked acidosis and reduced plasma osmolality. 3. The homoeostatic response to sodium depletion was associated with a reversal of sodium/potassium ratio in parotid saliva and a reduction of the rate of secretion. Appetite diminished. The extracellular fluid was halved as marked diuresis developed with considerable weight loss. Urinary and faecal sodium was reduced to zero. 4. On restoration of sodium balance by allowing the calves to drink sodium bicarbonate solutions the metabolic deviations were eliminated. 5. During sodium depletion the parotid gland was able to respond to transient reflex stimulation by increasing flow rate and the sodium concentration of the saliva. 6. When sodium depleted, the calves became restless and agitated and would run from the home pen to the operant procedure stand. The sodium depleted animals readily pressed a panel for sodium bicarbonate rewards in direct proportion to the degree of sodium imbalance. When the balance was restored the motivation to work for sodium bicarbonate disappeared. 7. The motivation which developed during sodium depletion was directed specifically towards the sodium ion. Lithium was an exception to this rule and sodium carbonate was aversive. 8. It is possible that in sodium depletion the glottal sodium taste receptors develop an enhanced threshold for sodium ions because of the reduced sodium content of the saliva. This effect would be abolished when the content of sodium was restored in saliva. 9. The correlation of operant reactions and sodium depletion suggests that the consequential metabolic effects activate changes in the central nervous system. 10. The metabolic changes which develop in parallel with the severity of the sodium deficit appear to be able to evoke behavioural changes with increase in salt appetite directed towards restoration of sodium balance.


The fate of exogenous arachidonic acid in guinea-pig isolated lung. 1. The fate of [14C]arachidonic acid perfused through the pulmonary circulation was studied in guinea-pig lungs perfused with Krebs solution. 2. Radioactivity in the lung effluent fell rapidly and by 10 min about 20% of the infused radioactivity had emerged. 3. Most (70%) of the effluent radioactivity was associated with products of cyclo-oxygenase activity, whereas in the lung tissue most of the retained radioactivity was present as phospholipid. 4. Radioactivity in phospholipid was distributed equally between three groups: phosphatidyl choline, phosphatidyl ethanolamine and the other phosphatides. 5. Addition of albumin to the Krebs solution perfusing the lung increased the proportion of effluent radioactivity to 50%, decreased the cyclo-oxygenase products but increased the label in phospholipid in lung. 6. Indomethacin, frusemide, bromcresol green and diethylcarbamazine all decreased biological activation of arachidonic acid. 7. Indomethacin, bromcresol green and diethylcarbamazine also decreased effluent radioactivity and cyclo-oxygenase products with minimal effects on the distribution of radioactivity in lung lipid. 8. It appears that the major metabolic pathway for exogenous arachidonic acid perfused through the pulmonary circulation was incorporation into phospholipid. Metabolism via cyclo-oxygenase only involved about 15% of the total substrate infused.


A kinetic study of the interactions between amino acids and monosaccharides at the intestinal brush-border membrane. 1. The influx of amino acids into guinea-pig intestinal rings in vitro is inhibited by monosaccharides, and that of monosaccharides by amino acids. Two hypotheses have been proposed to account for these heterologous interactions. According to the first, the cis hypothesis, there is an allosteric interaction between substrates binding to separate but related sites at the outer face of the brush-border membrane matrix. In contrast, the trans hypothesis envisages the interaction to result from a partial dissipation of the electrochemical sodium gradient due to the cotransport of each substrate with sodium ions. 2. In an attempt to distinguish between the merits of the two hypotheses, we examined the kinetics of the inhibition of phenylalanine influx by two sugars of widely different affinities, galactose and beta-methylglucoside. Since beta-methylglucoside carries more sodium into the cell than galactose, the trans hypothesis would predict it to be the stronger inhibitor, but in fact the opposite result is found. 3. Equations were developed to describe the inhibitions in accordance with the cis hypothesis. The satisfactory agreement between experimental observations and theoretical predictions provides support for the applicability of the model. Further implications of the polyfunctional carrier model are discussed.


Recovery of cat retinal ganglion cell sensitivity following pigment bleaching. 1. The threshold illuminance for small spot stimulation of on-centre cat retinal ganglion cells was plotted vs. time after exposure to adapting light sufficiently strong to bleach significant amounts of rhodopsin. 2. When the entire receptive field of an X- or Y-type ganglion cell is bleached by at most 40%, recovery of the cell's rod-system proceeds in two phases: an early relatively fast one during which the response appears transient, and a late, slower one during which responses become more sustained. Log threshold during the later phase is well fit by an exponential in time (tau = 11.5-38 min). 3. After bleaches of 90% of the underlying pigment, threshold is cone-determined for as long as 40 min. Rod threshold continues to decrease for at least 85 min after the bleach. 4. The rate of recovery is slower after strong than after weak bleaches; 10 and 90% bleaches yield time constants for the later phase of 11.5 and 38 min, respectively. This contrasts with an approximate time constant of 11 min for rhodopsin regeneration following any bleach. 5. The relationship between the initial elevation of log rod threshold extrapolated from the fitted exponential curves and the initial amount of pigment bleached is monotonic, but nonlinear. 6. After a bleaching exposure, the maintained discharge is initially very regular. The firing rate first rises, then falls to the pre-bleach level, with more extended time courses of change in firing rate after stronger exposures. The discharge rate is restored before threshold has recovered fully. 7. The change in the response vs. log stimulus relationship after bleaching is described as a shift of the curve to the right, paired with a decrease in slope of the linear segment of the curve.


Non-passive chloride distribution in mammalian heart muscle: micro-electrode measurement of the intracellular chloride activity. 1. Liquid ion-exchanger Cl- -sensitive micro-electrodes were used to make continuous measurements of the intracellular Cl activity, aCli, of quiscent sheep cardiac Purkinje fibres in vitro. 2. aCli was higher than that expected from a passive distribution, (which would have been about 5 mM). It was 3--4 times hiable; EC1 was about 35 mV positive to Em. It was over twice as high in the nominal absence of bicarbonate/CO2 (when the buffer-system was HEPES/O2) but was not always so stable, and ECl was about 20 mV positive to Em. 3. Experiments designed to assess the maximum possible error likely to occur in the measurement of aCli showed that this could not be large and that the estimates of ECl were accurate to within 8 mV. 4. The ability of Cl to move down both concentration and potential gradients was established by demonstrating a loss of aCli in Cl-free solutions and a gain when Em was depolarized positive to ECl in high-K solutions. In both cases, the changes were complete within about 100--160 min. 5. The decline of aCli in Cl-free solutions (glucuronate-substituted) was not significantly affected by changes of [Ca]o from 0 to 12 mM or by the depolarizations of Em of up to 60 mV that sometimes occurred in low or zero [Ca]o. 6. Only 2--3 mM-aClo was sufficient to impede substantially the ready loss of aCli in HEPES-buffered solutions. 7. In high-K solutions (45 mM), Cl appeared to be passively distributed since, at equilibrium, Em and ECl differed by less than 2 mV. 8. In HEPES-buffered Tyrode, ECl of quiescent papillary muscle of the guinea-pig was, on average, 39 mV positive to Em. 9. It is concluded that liquid ion-exchanger Cl- -sensitive micro-electrodes are suitable for studying the Cl regulation of sheep Prukinje fibres, and probably of other cardiac tissues. The measurements of resting aCli are quite accurate when using either HEPES or bicarbonate-buffered Tyrode. The results are discussed in relation to estimates of the apparent membrane Cl permeability under various conditions and the possible existence of an inwardly directed 'Cl pump'.


[Heat-induced salivary gland hypertrophy: change during chronic heat exposure (34 degrees C). (author's transl)]. 1 A slight rise in ambient temperature (34 degrees C) increased saliva secretion in the rat and this was accompanied by licking behavior, thus increasing heat loss by evaporation. 2 The rise in ambient temperature was accompanied by a hypertrophy of the submaxillary glands (Fig.1, 2), arising from activation of seromucous acini (Fig. 4, 5). 3 The hypertrophy reached a maximum after 2 to 4 days of heat exposure (Fig. 2); it was followed by a slow decrease. Normal values were obtained only after at least 3 weeks in the climatic chamber (Fig. 2, 3), which agreed with behavioral observations. Increased secretion of saliva may help to increase heat loss and maintain survival in a hot environment. 4 The absence of morphological changes in the sublingual g and and the evolution of the granular circonvoluted tubules (Fig. 6) contrast greatly with the hypertrophy of the submaxillary acinus. It is possible that heat-induced saliva secretion may be controlled by both sympathetic and parasympathetic systems.


[Gastric and intestinal appearances by abdominal ultrasound. The sign of brownian motion (author's transl)]. Gastric, as well as intestinal images, are always present on abdominal ultrasonic scans. Since they are difficult to analyse, such images are usually neglected. Morphological and dynamic criterial (as the "brownian movement sign") enable to identify stomach and intestine. It is then possible to avoid the misinterpretation of normal anatomic elements as pathological processes, and, from time to time, to diagnose specific gastrointestinal lesions.


[Bronchiolo alveolar carcinoma. 9 cases (author's transl)]. The authors try to define the criteria for the diagnosis of this unusual variety of bronchio pulmonary adenocarcinoma. They studied only 9 patients, 8 of whom had surgery which allowed to make a correlation between X-ray and morphological findings. The pathologist encountered the usual problems in the diagnosis of a primitive tumor since some metastasis have the same macroscopic and microscopic aspect. The relation between the radiographic image and the anatomical findings is emphasised. From a symptomatic and radiological point of view, the most frequent distinction was between the opaque round intra-pulmonary image and the chronic alveolar opacity. Other radiological types occurrence less frequently, such as the nodular or the hollowed type. The authors emphasize the pronostic importance of distinguishing the localized form, with a generally good prognosis following surgery, form the diffused form, which have a very poor prognosis. Even under the best of conditions, a radiological study must be supported by both surgery and pathology to be sure that the tumor in question is, in fact, strictly localized. The histogenesis of bronchio-alveolar carcinoma is briefly discussed in a study of histology and pathology.


[Radiological signs of primary sarcoma of the kidney in adults : a report on 5 cases (author's transl)]. Primary sarcomas of the kidney are extremely uncommon and the results of their angiographic study are rarely reported. A study of five cases that were confirmed histologically demonstrates the absence of specific clinical and urographic findings. Arteriographic appearances are variable and not related to the histological type. The poorly vascularized forms are traditionally the most frequent (2 out of 5 cases) but are not fundamentally different from adenocarcinomas. The diagnosis can be suspected, however, when there is an infiltrating peripheral tumor extending well beyond the capsule. The hypovascularized pseudocystic forms raise the same arteriographic problems as the adenocarcinomas. Arteriography can diagnose malignancy, but the diagnosis of sarcoma is usually impossible before operation.


[Radiological opacities after intra-articular injection of osmic acid. Relationship with the injection site (author's transl)]. Abnormal radiological opacities are sometimes observed after intra-articular injection of osmic acid. These opacities are radio-opaque because osmium is a heavy metal (atomic number = 76). They are usually found near the suprapatellar pouch which is the usual injection site. A parasynovial injection (or back flow from the joint cavity) of some of the osmic solution, followed by concentration and fixation of the osmic deposits at this level, seems to be the cause of these radiological opacities. This could be the reason for the poor clinical results encountered in some cases of osmic acid therapy followed by such deposits.


[Splenic trauma complicating translumbar aortography : a report on 2 cases (author's transl)]. Two very rare cases of splenic trauma following high translumbar aortography are described. Two types of clinical picture are observed : severe intraperitoneal hemorrhage, subcapsular and then intraperitoneal, from rupture of the spleen, and septic peritonitis following rupture of an intra- and perisplenic abscess. The authors review the frequency, mechanism, and prevention of complications following translumbar aortic puncture.


[Cellulitis of the leg as the presentation of pandiaphysitis in the child (author's transl)]. The authors report 6 cases of acute osteomyelitis of the leg, presenting with a very severe subcutaneous cellulitis and progressing to sub-periosteal abscess, then pandiaphysitis with major bone destruction at the 15th day, despite antibiotics. However, all these children recovered without sequelae, apart from one case. Early diagnosis was difficult and treatment started after an excessive delay in the majority of cases. If it can be performed on an emergency basis, Technetium bone scan is useful in making the diagnosis. In the absence of the type of examination, any case of severe subcutaneous cellulitis in a child must be considered as a potential osteomyelitis and treated as such.


[Retroperitoneal gas images following subperitoneal hollow viscus rupture (author's transl)]. Three cases of traumatic rupture of a subperitoneal hollow viscus are reported : two duodenal lesions and one rectal wound. Early diagnosis was possible in all three cases by the recognition of retroperitoneal gas on simple radiographs of the abdomen, which was evidenced by images containing air bubbles, which were also fasciculated and fairly fixed. They were unilateral, on the right side, and usually associated with disappearance of the psoas shadow in duodenal injuries. Rectal perforation produces a bilateral distribution of the retroperitoneal gas, which extends to the subperitoneal fat and the posterior extraperitoneal space, according to the amount of effusion.


[Aneurysmal cyst of the orbit (author's transl)]. A child of 11 years of age was found to have an aneurysmal cyst of the orbit. This is an extremely rare cause for tumoral exophthalmia in children and the localization in this region is also very unusual. Only 14 cases are reported in the published literature. The main differences in relation to those occurring in the long bones and vertebrae are the constant absence of pain and the almost exclusively osteolytic radiological appearance.


[Changes in angiographic recordings during reflux nephropathy (author's transl)]. On one of the few occasions when it was possible to review angiographic recordings taken at five-year intervals, in a patient with reflux nephropathy, the authors use the results to emphasize that it is always very difficult to decide whether a small kidney, associated with reflux, is congenital or acquired. The reflux must in any case be corrected.


[Macrodystrophia lipomatosa. Angiographic aspects (author's transl)]. A new case of this unusual entity is reported. The patient, male aged 43 has an hypertrophy of the first and second left fingers. Radiographic examination shows bony overgrowth and marked soft tissue thickening. Arteriography did not show any evidence of angioma or arteriovenous fistula. Histologic examination shows deposits of fat in soft tissue thickening. Macrodystrophia lipomatosa is a rare disease, usually confined to one or two digits of the hand, and sometimes of the foot. A dysembryoplasic aetiology could be sustained, and this entity is very close from others bone or soft-tissue hamartomas.


[Right subclavian arteria lusoria with anomaly of the origin of the two vertebral arteries. A cause of functional vertebrobasilar insufficiency (author's transl)]. Functional disturbances of arterial vertebrobasilar insufficiency may be correlated to anomalies of the origin of the vertebral arteries especially in young patients. The authors describe 1 case of right subclavian arteria lusoria with anomaly of the origin of both vertebral arteries (aortic on the left and from the primary carotid artery on the right).


Problem behaviour in primary health care. Primary health care can be regarded as the boundary between society as a whole and the medical system. Many of the problems patients bring to doctors in primary care are concerned with their personalities and life situation, and can be considered together as problems of human behaviour.On being questioned in a waiting room, 15 per cent of patients considered their problem "psychosocial only", and an additional 13 to 14 per cent "both somatic and psychosocial".I believe that the concept of the primary health care team is particularly valuable in managing problems of behaviour, and nondoctor members of the team play a crucial role.In my opinion it is questionable whether people's life problems should be channelled through primary health care, but in the meanwhile it seems clear that in most western societies the fact is they are.


Evaluation of behavior therapy intervention in general practice. Thirty general practitioner consultations with patients with psychological problems referred to a clinical psychologist for behaviour therapy, were examined. Treatment was carried out wholly within the practice. Consultations for advice and psychotropic drug prescriptions were compared during one year, both before and after treatment, and were found to be reduced by over 50 per cent following treatment. Contact with clinical psychology services, therefore, considerably reduced the demand made by these patients for general practitioner time.


Psychological treatment in general practice. A clinical psychologist was attached to two group practices in Sheffield for 1.5 sessions each per week. A total of 238 patients was seen during 26 months. Of those completing therapy, 72 per cent made satisfactory progress. In the three months after stopping treatment patients made significantly fewer (36 per cent) visits to the surgeries and received significantly fewer (50 per cent) prescriptions for psychotropic drugs than in the three months before referral. These changes were maintained one year later in the three-month period 12 to 15 months after discharge. The result has been to provide largely successful therapy for a population of patients for whom adequate treatment was previously unavailable. This suggests that it would be worthwhile to expand psychological services in general practice still further as advised by the Department of Health and Social Security.


Counselling in general practice.

Counselling in general practice. In 1976, a group practice in South Oxfordshire established a counselling service. The counsellor is available in the health centre for three half-day sessions per week, and we describe a survey of the subjective and objective effects of counselling on the first 80 patients who used this service. There was an improvement, as measured by the feelings of the patients and doctors, and by some reduction of psychotropic drugs and medical consultations. The majority of the patients who returned the questionnaires said they preferred to see the counsellor rather than the general practitioner for their problem.


Integrating hospital and family practice posts in vocational training for family medicine. Postgraduate training programmes for family medicine are developing simultaneously in many different parts of the world. In the UK continuity of care is highly valued but vocational training schemes have not been able to provide continuity of care for patients throughout a three-year training course.In Puerto Rico a vocational training scheme exists in which residents are enabled to integrate their hospital and family practice work throughout a three-year course. This arrangement is described and compared and contrasted with vocational training in the UK.


Compliance with prescribed medicines: a study of elderly patients in the community. Compliance with regular medicine taking has been assessed in 81 patients, aged 65 and over, living at home. Interview assessment, home tablet count, and retrospective review of general practice prescription record cards provided three indices of compliance.Deviation by more than 10 per cent from absolute adherence to the prescription was found in 53 per cent of all tablet counts and was significantly more common in women than in men. Errors were also more common when medicines were to be taken more than once daily.The compliance index obtained by inspection of prescription records correlated closely with the index calculated from tablet counts (r(s) = 0.68; p < 0.001) for 129 separate medicines taken regularly. Poor compliance with an individual medicine could be predicted accurately in 66 per cent of cases. A combination of prescription record inspection and interview assessment increased the accuracy of this prediction to 86 per cent.These findings suggest that, using simple methods, the level of compliance can be accurately predicted in a substantial number of elderly patients at home.


Improving drug compliance in general practice. Patients of all ages make serious mistakes with their medicines, especially if several are prescribed at once.Taking medicines involves a great deal of physical and mental work. The best way to help patients take medicines accurately is to reduce this work by packing together all tablets taken at the same time of day. Many elderly patients have relatives who could pack their medicines in this manner.


The changing pattern of general practitioner drug prescribing in the National Health Service in England from 1970 to 1975. We describe the changing pattern of general practitioner prescribing in the National Health Service in England between 1970 and 1975.The percentage increase in items of prescriptions had increased 10 times as much as the percentage increase in the population in the same period. One of the reasons given is that there may be a growing tendency to give a prescription when it would be better to give advice.The evidence seems to support other findings that the profession responds much more widely to reports on the good effects of a drug than it does to its adverse effects.


Drugs and prescribing: what the patient thinks. Two hundred and forty-one patients, 173 females and 68 males, completed questionnaires designed to identify their knowledge of drugs and attitudes to doctors' prescribing behaviour. These results were compared with those of 35 ancillary staff, 277 schoolchildren, 55 student nurses, 69 medical students, and 78 general practitioners. Although over 80 per cent of patients thought that heroin was a drug, only 10 per cent thought that penicillin should be so classified. Only two per cent of patients thought it was safe for doctors to prescribe without first seeing the patient, although 80 per cent of general practitioners thought that this was sometimes acceptable.Seventy per cent of doctors thought that antibiotics, tranquillizers, hypnotics, and antidepressants were over-prescribed and nearly half the patients appeared to agree with them.More patients thought that antibiotics were designed to kill viruses than bacteria, over a quarter thought that these preparations were the best form of treatment for a cold, and almost half expected diarrhoea to be treated with an antibiotic.Doctors need to spend more of their time in simple health education. By doing so they could reduce their future workload and the nation's drug bill.


A simple method of encouraging postgraduate learning in therapeutics. I describe a new method of encouraging groups of general practitioners to discuss their prescribing policies by revealing their differing views of the suitability of pre-selected drugs for use in specified clinical situations. Subjective evaluation was favourable and the method is clear and easy to arrange.


Infant feeding and overweight in two Oxfordshire towns. In a study of feeding and growth in the first year of life in two Oxfordshire market towns, the frequency of overweight babies was the same for the 'intervention' town (where a research health visitor gave intensive advice to mothers on feeding) as for the control town. Eighteen per cent of bottle-fed infants and three per cent of those breast fed were overweight at one year. It seems that an increase in the number of health visitors does not affect the frequency of overweight infants, but it may be that a greater emphasis on breast feeding might reduce the frequency.


Trainee research in South-East Scotland. I describe the experience of the South-East Scotland Faculty of the Royal College of General Practitioners with trainee research projects during the last few years.


Patients' expectations and intention to self-medicate. I studied patients' expectations of receiving a prescription after a consultation with their general practitioner and their intention to buy a remedy from the chemist after leaving the surgery.Of a group of 368 patients, 56 per cent expected to receive a prescription and 24 per cent intended to self-medicate. A striking variation was found among patients attending each of the five doctors participating in the study. Patient expectation closely agreed with the prescribing rate per partner. No consistent relationship was found between a low prescribing rate and high self-medication rates. I suggest that by reducing prescribing and encouraging patients to be self-reliant in the management of minor ailments, it might be possible to reduce a general practitioner's workload and the amount of money spent on prescribing in general practice.


A study of repeat prescription cards in a general practice. A study of repeat prescription cards in a general practice revealed problems in good record keeping and patient recall. A system involving a repeat register was therefore developed to create an easily accessible practice record and a recall procedure was initiated. Greater control over repeat cards is now possible.Examination of the age and sex of the card-holders showed a high proportion of elderly females. By scrutiny of the contents of the cards, a profile of prescribing in the practice was drawn and this was used as material for discussion of prescribing policy.Finally, the system has potential to monitor patients with chronic diseases where regular medication is essential.


Anticoagulant care in one urban group practice. A system of supervising anti-coagulant care was introduced to a busy urban group practice. The results of the first two years' operation of this system show that there were 4.4 prothrombin time (PT) assessments per week, about half of which were performed on working patients. The system was acceptable to patients and practitioners and some unexpected advantages were found.


How much do patients know? A multiple choice question paper for patients in the waiting room. A questionnaire about knowledge of personal preventive medicine, treatment, and the appropriate use of health services was put to a population of patients attending their doctors' surgeries. The population was probably biased toward the younger and those willing to fill in such a questionnaire. The results showed a social class gradient in knowledge and a distressing degree of ignorance on some topics. Suggestions are made for using the method in a positive educational way in practices, and for further studies with improved methods.


The need for health care--a pilot survey with general practice. A feasibility study was carried out in two places in Wiltshire of a method of ascertaining the morbidity of the population. Traditional medical history taking and examination of the individuals were completed in a random sample of the population, of whom 89 per cent were contacted. The method appears feasible for a survey of sufficient size to measure morbidity and the study gave useful preliminary indications of unmet health care need. The cost of such a larger survey would be small in relation to the sums involved in health care planning.


C-reactive protein in the differential diagnosis of gynecologic pathology. A qualitative assay for the presence of C-reactive protein (CRP), with a threshold of approximately 1 mg per deciliter, was performed on 121 gynecologic patients who presented to the University of Chicago, Chicago Lying-In Hospital for various complaints. CRP results divided patients with inflammatory processes from those without inflammation or necrosis with an accuracy of over 98%. The method, which is quick and inexpensive, allows CRP to be a useful tool in the differential diagnosis of pelvic pain and masses and further may be useful in the assessment of the efficacy of antibiotic regimens in the treatment of pelvic inflammatory disease.


Scintiscanning in ankylosing spondylitis: a clinical, radiological and quantitative radioisotopic study. Twenty-six patients with ankylosing spondylitis and 10 control subjects had quantitative dorso-lumbar and sacroiliac scintigraphy performed using 99mtechnetium methylene diphosphonate. No difference was found in the mean uptakes of radionucleide at each vertebral level or in the sacroiliac joints between the diseases patients and controls. No correlation was found between radionucleide uptake and radiological score, pain and tenderness assessments. The large variation in quantiative measurements resulted in a large overlap between control and diseased patients and it is unlikely that scintigraphy will be of diagnostic value in the absence of improved methodology.


Isolated Candida parapsilosis arthritis in a heroin addict. A case of isolated Candida parapsilosis arthritis involving the shoulder of a heroin addict is described. Amphotericin B successfully eradicated the infection after failure of flucytosine. Optimal therapy for this condition has not been determined.


Frostbite arthritis.

Frostbite arthritis. We report a case of unilateral frostbite arthritis in a 58-year-old male. Clinical and radiological changes mimicked those of erosive osteoarthritis. Patients with this presentation should be carefully questioned for a history of exposure to cold, and frostbite arthritis should be considered in the differential diagnosis.


Apatite-associated arthropathy: a clinical study of 14 cases and of 2 patients with calcific bursitis. Fourteen cases of acute calcific periarthritis and 2 cases of acute calcific bursitis are described. All patients had radiologic periarticular calcific deposits. Synovial fluid was available from 8 patients. Hydroxyapatite crystals were positively identified in 1 by x-ray diffraction analysis and by scanning and transmission electron microscopy. Apatite-associated arthropathy likely represents a form of crystal-induced inflammation. Three articular syndromes can be recognized; acute calcific periarthritis, acute (calcific) arthritis and a subacute-to-chronic arthritis resembling osteoarthritis. To improve patient classification, diagnostic criteria are proposed.


Polymorphonuclear leukocyte responses to monosodium urate crystals: modification by adsorbed serum proteins. The effects of protein absorption to monosodium urate monohydrate (MSU) crystals on crystal-induced lysosomal enzyme release from human neutrophils were studied. Native crystals produced prompt release of both lysosomal and cytoplasmic enzymes, suggesting that they are directly membranolytic for the neutrophil. When albumin, IgM, or beta-lactoglobulin were adsorbed to MSU crystals, lysis was blocked and lysosomal enzyme release was negligible. Prior incubation of crystals with 20% human serum or adsorption of IgG resulted in inhibition of lysis but enhancement of lysosomal enzyme liberation. This non-cytolytic lysosomal enzyme release induced by IgG-coated crystals may be important in the pathogenesis of acute gouty arthritis.


Procainamide-induced lupus erythematosus: report of a case with a large pericardial effusion and fluid analysis. A patient with procainamide lupus erythematosus had a large pericardial effusion. As in other reported cases histology revealed a fibrinous mononuclear pericarditis and the pericardial fluid was a serosanguinous inflammatory exudate with a high LDH level and normal glucose concentration. The ANF and LE cell preparation were positive in the fluid but the C3 complement was normal. The frequency of pericarditis is similar in systemic and drug-induced lupus erythematosus yet low complement levels need not occur. Complement activation may therefore be unnecessary for the development of either type of lupus pericarditis.


The diagnostic value of 99m Tc-diphosphonate bone imaging in transient osteoporosis of the hip. We present topographic and quantitative studies of 99m Tc-diphosphonate bone scans from 46 patients and 25 control subjects in which we found transient osteoporosis of the hip (TOH) (12 cases--2 bilateral), early aseptic osteonecrosis of the femoral head (19 cases--2 bilateral), early coxitis (11 cases), and stress fracture of the femoral neck (4 cases). Active TOH was characterized by intense, homogeneous increased uptake of the entire femoral head, extending to the acetabulum and the neck, and sometimes to the shaft. The scintigram of TOH differed greatly from that in the other hip disorders studied. Bone scintigraphy can help to diagnose the cause of pain in a hip before definite roentgenographic signs appear.


Gangrene of a foot secondary to systemic lupus erythematosus with large vessel vasculitis. A 28-year-old man developed gangrene of a foot leading to a below-the-knee amputation. Although initially diagnosed as atherosclerotic vascular disease, clinical and laboratory findings of systemic lupus erythematosus (SLE) developed over the next 18 months. Histologic review of popliteal and femoral artery specimens showed acute and chronic changes consistent with the vasculitis of SLE. Subsequent treatment with prednisone controlled the vasculitis as well as the other clinical manifestations of SLE. The diagnosis of SLE should be considered in patients with large vessel peripheral vascular disease who lack the typical findings of the more common predisposing causes.


Precipitation membranes: III. Reversible changes of membrane properties induced by alterations in ionic concentrations. The conditioned state of a precipitation membrane with its particular properties exists within a limited range of membrane potentials and requires certain minimum concentrations, Clim, of the generating ions in the adjoining solutions. We investigated these quantities for the BaSO4 cellophane membrane and found Clim to be 10 X 10(-5) N (0.5 X 10(-4) M), equally for Ba++ and SO4--. Beyond these limits, the membrane becomes deconditioned. This transformation is a reversible process provided the limits have not been surpassed too far. The capability for de- and reconditioning is a characteristic and unique property of precipitation membranes, not found in other membrane systems. The phenomenon is explained by the adsorption theory for precipitation membranes. It allows wide modifications and quick variations of the electrical properties and permeability of the membrane in an easy and reversible manner.


Effects of external sodium and cell membrane potential on intracellular chloride activity in gallbladder epithelium. Conventional and Cl-selective liquid ion-exchanger intracellular microelectrodes were employed to study the effects of extracellular ionic substitutions on intracellular Cl activity (aCli) in Necturus gallbladder epithelium. As shown previously (Reuss, L., Weinman, S.A., 1979; J. Membrane Biol. 49:345), when the tissue was exposed to NaCl-Ringer on both sides aCli was about 30 mM, i.e., much higher than the activity predicted from equilibrium distribution (aCleq) across either membrane (5--9 mM). Removal of Cl from the apical side caused a reversible decrease of aCli towards the equilibrium value across the basolateral membrane. A new steady-state aCli was reached in about 10 min. Removal of Na from the mucosal medium or from both media also caused reversible decreases of aCli when Li, choline, tetramethylammonium or N-methyl-D-glucamine (NMDG) were employed to replace Na. During bilateral Na substitutions with choline the cells depolarized significantly. However, no change of cell potential was observed when NMDG was employed as Na substitute. Na replacements with choline or NMDG on the serosal side only did not change aCli. When K substituted for mucosal Na, the cells depolarized and aCli rose significantly. Combinations of K for Na and Cl for SO4 substitutions showed that net Cl entry during cell depolarization can take place across either membrane. The increase of aCli in depolarized cells exposed to K2SO4-Ringer on the mucosal side indicates that the basolateral membrane Cl permeability (PCl) increased. These results support the hypothesis that NaCl entry at the apical membrane occurs by an electroneutral mechanism, driven by the Na electrochemical gradient. In addition, we suggest that Cl entry during cell depolarization is downhill and involves an increase of basolateral membrane PCl.


Interactions of Folch-Lees proteolipid apoprotein with planar lipid bilayers. Water-soluble Folch-Lees proteolipid apoprotein from bovine CNS white matter induces a voltage-dependent conductance in black lipid membranes. Na+ is required for the induced conductance change but the established conductance has very low ionic selectivity. The induced conductance fluctuates with a minimum amplitude of 10(-11)--10(-10) mho. The magnitude of the conductivity change is dependent on protein concentration and on the composition of lipid bilayers. At a fixed voltage the induced conductance of a phosphatidylcholine-cholesterol membrane is proportional to the sixth power of the protein concentration and the first power of Na+ concentration. The interactions between the apoprotein and the lipids are both electrostatic and hydrophobic, but the interaction leading to the conductance increase appears to be mainly hydrophobic. Both the increase in conductance and the current fluctuations remain after extensive washing of the chambers to remove the protein. Furthermore, pronase or glutaraldehyde added to either the cis or trans side of the membrane does not affect the apoprotein-established conductance. However, if the bilayer is formed in the presence of both the apoprotein and pronase or if the apoprotein is treated with pronase prior to its addition to the chamber, no conductance change is observed. The association of the apoprotein with the membrane thus appears to render the protein inaccessible to proteolytic digestion, suggesting that the apoprotein is at least partially imbedded in the membrane interior.


Partial purification of the sugar carrier of intestinal brush border membranes. Enrichment of the phlorizin-binding component by selective extractions. The [3H] phlorizin-binding component of brush border vesicles was enriched in situ by negative purification. Several procedures, known to effect selective solubilization of membrane components, were used separately or in combination to remove proteins unrelated to the binding. Deoxycholate ruptured the vesicles and released 67% of their protein, thereby increasing the specific [3H] phlorizin-binding activity of the pellet three-to fourfold. Extracting the deoxycholate-pellets with either NaI or alkaline solutions released up to 38% of the deoxycholate-insoluble protein without significantly affecting phlorizin binding. The polypeptide composition of the membranes at the different stages was analyzed by NaDodSO4-polyacrylamide gel electrophoresis. A number of polypeptides present in the original vesicles could be ruled out as essential components of the [3H] phlorizin binding entity. Intact and deoxycholate-treated vesicles were subjected to proteolytic attack. Papain liberated sucrase and isomaltase from intact vesicles, but affected neither other Coomassie-stained bands nor phlorizin binding. Neither the protein composition nor the binding properties of sealed vesicles were influenced by trypsin or chymotrypsin. However, all the proteolytic enzymes tested on deoxycholate-treated membranes substantially reduced [3H] phlorizin binding and produced concomitantly the disappearance of several bands from the electrophoretic profile. Pretreatment of vesicles with papain, followed by deoxycholate extraction and incubation in alkaline media, increased the specific binding activity of the membranes up to ninefold by removing close to 90% of the protein. A limited number of polypeptides are suggested as possible candidates for the glycoside-binding site of intestinal brush borders.


Development of electrical coupling and action potential synchrony between paired aggregates of embryonic heart cells. Pairs of spheroidal aggregates of embryonic chick heart cells, held in suction pipettes were brought into contact and allowed to synchronize their spontaneous action potentials. Contractions were suppressed with cytochalasin B. Both intracellular and extracellular electrodes were used to analyze the development of synchrony. Electric coupling occurred in three phases. During phase I electrical interactions were absent despite close physical contact. Phase II was characterized by partial synchrony. Action potentials in the faster aggregate (F) induced small depolarizations in the other member of the pair (S). These depolarizations sometimes triggered action potentials in S depending on when during the diastolic depolarization in S they occurred. In these cases both the latency between the action potentials (L) and the fluctuations in latency (VL) were large. At the end of phase II the aggregates often passed through a brief period when functuation in interbeat interval in both increased noticeably. In phrase III, beginning about 8 min after initial contact, action potentials were completely entrained at a certain L. During the subsequent 20--40 min L fell along an approximately exponential time course from about 130 to less than 1 msec, while VL declined in parallel. When well-coupled aggregates were pulled apart and immediately pressed back together, they re-established synchronization according to the usual three-phase time course. Synchronized aggregates could be partially decoupled by separating them just far enough to reduce the area of mutual contact. Pairs joined only by cellular strands maintained entrained action potentials with long latencies for many minutes. These results indicate that electronic junctions form between the paired heart cell aggregates causing the gradual development of action potential synchrony.


Modification of the Reichert FC-2 cryoattachment to improve ultrathin sectioning reproducibility. Modifications of the Reichert FC-2 cryomicrotome attachment which facilitate sectioning of frozen material are described. Most valuable was the construction of a specimen holder chuck made of brass and connected to the specimen arm with a glass rod. Other changes include improved shielding from heat influx, a constant nitrogen pressure cooling system and a stable cryochamber mount. These modifications considerably improve reproducibility.


Application of differential interference contrast with inverted microscopes to the in vitro perfused nephron. The study of in vitro perfused individual nephron segments requires a microscope which provides: (1) easy access to the specimen for measurement of cellular solute flux and voltage; (2) an image with high resolution and contrast; (3) optical sectioning of the object at different levels; and (4) rapid recording of the morphological phenomena. This paper describes an example of commercially available apparatus meeting the above requirements, and illustrates its efficiency. The microscope is of the inverted type (Zeiss IM 35) equipped with differential-interference-contrast (DIC) with a long working distance, and an automatically controlled camera system. The microscopic image exhibits cellular and intercellular details in the unstained transporting mammalian nephron segments despite their tubular structure and great thickness and makes obvious function-structure correlations (e.g. cell volume changes); luminal and contraluminal cell borders are well resolved for controlled microelectrode impalement.


Frost-weathering on Mars: experimental evidence for peroxide formation. A laboratory study of the interaction of H2O frost with samples of the minerals olivine (Mg,Fe)2SiO4 and pyroxene (Mg,Fe)SiO3 at -11 degrees C to -22 degrees C revealed that an acidic oxidant was produced. Exposure of the frost-treated minerals to liquie H2O produced a sudden drop in pH and resulted in the production of copious O2(g) (as much as approximately 10(20) molecules g-1). Exposure of frost-treated samples to 5 ml of 0.1M HCOONa solution resulted in the rapid oxidation of up to 43% of the formate to CO2(g). These reactions were qualitatively similar to the chemical activity observed during the active cycles of the Viking lander Gas Exchange and Labeled Release Biology experiments. Attempts to identify the oxidant by chemical indicators were inconclusive, but they tentatively suggested that chemisorbed hydrogen peroxide may have formed. The formation of chemisorbed peroxide could be explained as a byproduct of the chemical reduction of the mineral. The following model was proposed. H+ was incorporated into the mineral from surface frost. This would have left behind a residual of excess OH-(ads) (relative to surface H+). Electrons were then stripped from the surface OH-(ads) (due to the large repulsive potential between neighboring OH-(ads)) and incorporated into the crystal to restore charge balance and produce a chemical reduction of the mineral. The resultant surface hydroxyl radicals could then have combined to  form the more stable chemisorbed hydrogen peroxide species. While the chemisorbed peroxide should be relatively stable at low temperatures, it should tend to decay to O(ads)+ H2O(g) at higher temperatures with an activation energy of greater than or approximately 34 kcal mole-1. This is consistent with the long-term storage and sterilization behavior of the Viking soil oxidants. It is possible that as little as 0.1--1% frost-weathered material in the martian soil could have produced the unusual chemical activity that occurred during the Viking Gas Exchange and Labeled Release experiments.


Chemical and physical microenvironments at the Viking landing sites. Physical and chemical considerations permit the division of the near-surface regolith on Mars into at least six zones of distinct microenvironments. The zones are euphotic, duricrust/peds, tempofrost, permafrost, endolithic, and interfacial/transitional. Microenvironments vary significantly in temperature extremes, mean temperature, salt content, relative pressure of water vapor, UV and visible light irradiance, and exposure to ionizing radiation events (100 Mrad) and oxidative molecular species. From what is known of the chemistry of the atmosphere and regolith fines (soil), limits upon the aqueous chemistry of soil pastes may be estimated. Heat of wetting could reach 45 cal/g dry soil; initial pH is indeterminate between 1 and 10; ionic strength and salinity are predicted to be extremely high; freezing point depression is inadequate to provide quantities of liquid water except in special cases. The prospects for biotic survival are grim by terrestrial standards, but the extremes of biological resiliency are inaccessible to evaluation. Second-generation in situ experiments which will better define Martian microenvironments are clearly possible. Antarctic dry valleys are approximations to Martian conditions, but deviate significantly by at least half-a-dozen criteria.


The photolytic degradation and oxidation of organic compounds under simulated Martian conditions. Cosmochemical considerations suggest various potential sources for the accumulation of organic matter on Mars. However the Viking Molecular Analysis did not indicate any indigenous organic compounds on the surface of Mars. Their disappearance from the top layer is most likely caused by the combined action of the high solar radiation flux and various oxidizing species in the substances and a sample of the Murchison meteorite was tested under simulated Martian conditions. After adsorption on powdered quartz, samples of adenine, glycine and naphthalene were irradiated with UV light at various oxygen concentrations and exposure times. In the absence of oxygen, adenine and glycine appeared stable over the given irradiation period, whereas a definite loss was observed in the case of naphthalene, as well as in the volatilizable and pyrozable content of the Murchison meteroite. The presence of oxygen during UV exposure caused a significant increase in the degradation rate of all samples. It is likely that similar processes have led to the destruction of organic materials on the surface of Mars.