Weekly artificial kidney: personal monitor with cartridge re-use.

Cartridge re-use is now successful in centre and home haemodialysis. The economic advantage of re-use is remarkable even in the case of a single re-use. However, hepatitis and pyrogenic reactions may follow re-use and are a source of possible contamination. The problem of storing sterilised cartridges also arises. In order to reduce the work load and simplify preparation and re-use the authors have developed a simple 'personal monitor' that permits automatic recovery of the cartridge and eliminates handling. In our unit this 'personal monitor' has been used for 14 months without complications and with considerable saving. By using the same cartridge three times for each patient, the aim of a 'weekly kidney' has been achieved.


Undried cellulose gel film-- a high permeability dialysis membrane.

Undried cellulose gel film manufactured by British Cellophane Ltd (BCL) has been evaluated in vivo and in vitro. Results obtained indicate that undried cellulose gel film is superior in terms of ultrafiltration and middle molecular clearance to the widely used Cuprophan membrane and comparable with the Rhône Poulenc AN69 Acrylopolynitrile membrane for middle molecular clearance. The gel film is suitable for use with conventional dialysis equipment and in terms of residual blood volume, leak rate and pyrogenicity is indistinguishable from cuprophan.


Migration of plasticiser from haemodialysis blood tubing.

Di-2-ethylhexyl phthalate (DEHP) was found to migrate from polyvinyl chloride (PVC) blood tubing into human blood during both in vivo and in vitro haemodialysis. DEHP blood level increased during in vivo dialysis but decreased again toward the end of a six hour dialysis period. During in vitro haemodialysis of outdated human blood DEHP accumulated up to 5580 ppb. Although toxic effects have not yet been observed, we believe plastic tubing that does not contain extractable materials should be developed.


Comparison of two strategies for short dialysis using 1m2 and 2m2 surface area dialysers.

Two matched groups of patients were dialysed either thrice weekly on a double re-used Gambro (2m2) for four and a half hours per dialysis (Group A) or thrice weekly five hours per dialysis on a single non re-used Gambro (1m2) (Group B). There was no significant differences in measured parameters of nitrogen retention between the groups, nor did the mean motor nerve conduction velocity alter significantly in any patient. Both groups preferred short dialysis. No manifestations of inadequate dialysis appeared up to 18 months even in bilateral nephrectomised patients of whom there were 2 in each group. Group B experienced significantly fewer hypovolaemic symptoms during dialysis and the single system in thus preferred. The mean dialysis index in Group A was 1.0 and 0.9 in Group B. These results suggest that a dialysis index of 1.0 overestimates dialysis needs.


A comparison of short and long haemodialysis.

Two groups of patients treated by short (Milan) and long (Newcastle) haemodialysis were compared for incidence of symptoms and biochemical control. Short dialysis corrected urea and creatinine as well but control of potassium and phosphate were similar. The only apparent penalties to be paid by short dialysis patients were a higher incidence of itching, tingling or numbness, impairment of vibratory sense and difficulty in controlling blood pressure. The short dialysis group had higher haemoglobin and less dyspnoea, muscle weakness and dizziness after dialysis.


Comparative aspects of tumours of the central nervous system in the dog.

A wide variety of tumours of the brain occur in the dog, most commonly in the Boxer breed. Tumours may arise from the subependymal plate which may influence the parts of the brain destroyed and hence the pattern of clinical signs. Because of the small capacity of the dog's skull, vital neurological structures are quickly destroyed and the time course of these events is much shorter than in man. The high incidence of tumours in the Boxer would suggest that this breed might afford a useful model for clinical treatment using, for instance, cytotoxic agents.


Blockade of the postorchidectomy increase in gonadotropins by implants of atropine into the hypothalamus.

Bilateral implants of atropine sulphate were placed in various loci in the brain or into the anterior pituitary in male rats and the effects of the implants on the postcastration rise in plasma FSH and LH was determined. The increase in both gonadotropins at 16 hr after castration still occurred in animals with implants in the cerebral cortex. The postcastration rise of both FSH and LH was blocked by atropine implants in the anterior, middle, or posterior hypothalamus but was not interfered with by control implants of cholesterol. Bilateral implants of either cholesterol or atropine into the anterior pituitary failed to alter the increase in plasma LH following castration but both types of implants interfered with the postcastration rise in FSH, possibly because of trauma to the pituitary from the cannulae. It is suggested that hypothalamic cholinergic synapses may play a role in stimulating the increased LHRH release which induces the postcastration rise in gonadotropins.


Dose-response hyperplasia and neoplasia from feeding N-2-fluorenylacetamide (2-FAA) to BALB/c mice for varying time intervals.

Hyperplasia induced by N-2-fluorenylacetamide requires the continuous presence of the chemical for its maintenance. Feeding the chemical at levels of 8 to 86 ppm results in a dose-response related urinary bladder hyperplasia and, after 9 to 12 months, in bladder neoplasia at the higher dose levels. Neoplasia of the lungs, liver, parotid gland, lacrimal gland, harderian gland, and submaxillary gland was also observed. Measurement of oncogenic viruses revealed no synergism with 2-FAA and no relationship between virus counts and neoplasia. Calcareous pericarditis was observed and most general toxicological effects occurred in the liver. A pronounced sex difference in response was observed with the males giving greater responses than the females in all instances.


Observations on hexachlorophene-induced paralysis in the cat and its antagonism by hypertonic urea.

Cats given HCP (20 mg/kg) orally each day developed hindlimb paralysis and greatly elevated CSFP (174 mm saline; 19 mm in controls) in 3 to 5 days. "Status spongiosis" was seen in white matter only in sections of brain and cord. There was no dilation of cerebral ventricles, or damage to their ependymal linings or to the arachnoid villi. The neurological picture excluded any but a terminal effect upon cranial nerve function. There appeared to be no damage to neurons, and recovery of survivors was complete within 6 weeks after cessation of HCP administration. Elevated CSFP in paralyzed anesthetized cats was quickly lowered by an average of 256 mm by slow iv administration of 30% urea (2 g/kg in 10% invert sugar). Unanesthetized cats similarly paralyzed were able to stand and walk for up to 4 hr after this treatment. Neither acetazolamide nor prednisolone alone had any effect, nor did coadministration with urea enhance the effect of urea. The HCP lesion does not appear to be inflammatory in origin, nor does it seem to involve ventricular obstruction or overproduction  of cerebrospinal fluid. The reappearance of paralysis about 4 hr after osmotic diuresis, which corresponds with the elimination of urea, suggests that prolonged iv infusion with urea or a similar osmotically active substance may have significant clinical value in the management of HCP poisoning.


Longitudinal tension of anterior tibial artery segments during constrictor responses.

Longitudinal tensions were recorded from in situ isolated segments of dog anterior tibial arteries during vasoconstrictor responses. Two factors appeared to be responsible for longitudinal tensions occurring during vasoconstrictor responses. One was due to changes in intraluminal pressure and appeared to be the dominant factor. Increases in intraluminal pressures produced decreases in longitudinal tensions, indicating that the vessel segments were elongated. Thus, increases in intraluminal pressure passively stretched the blood vessel walls so that increases in both the circumferential and longitudinal axes of the vessel segment occurred. These findings agree with similar findings reported earlier (4, 7, 8). The other factor was apparently due to changes in longitudinal tension produced by vascular smooth muscle contraction. In some cases longitudinal tension changes were positive, in others they were negative. Increases in longitudinal tension were probably the result of contractions of helical smooth muscle elements. Decreases in tension may have been due to displacement of tissue parallel to the long axis of the vessel as smooth muscle elements contracted.


Therapeutic activity of pretazettine, a narcissus alkaloid on Rauscher leukemia: comparison with tazettine and streptonigrin.

The therapeutic activity of narcissus alkaloid pretazettine HC1 (PTZ) on established Rauscher leukemia has been demonstrated and compared with the isomer tazettine (TZ) and an antibiotic, streptonigrin (SN). PTZ and SN showed remarkable prolongation effect on the life span of the leukemic mice and the antiviral activity has been confirmed in mouse 3T3 cells infected with Rauscher virus. TZ showed no significant activity in the leukemic mice and was inhibitory to the virus growth in the cells at much higher doses than PTZ. It is suggested that the stereochemical rearrangement from PTZ to TZ inactivates the biological activity of PTZ.


Zinc metabolism and homeostasis in rats fed a wide range of high dietary zinc levels.

Zinc metabolism and homeostasis were studied in young growing rats fed a 38 ppm zinc diet with added zinc levels ranging from 0 to 8400 ppm for 21 days. High dietary zinc did not cause toxicity symptoms. Stable zinc in feces increased linearly with dietary zinc intake but fecal 65Zn, from a single oral dose, did not increase above the 1200 ppm dietary level. Stable zinc in liver, kidney, and tibia increased two to three times with 2400 ppm added zinc, but was not further elevated until 8400 ppm was fed. Stable zinc in muscle and heart was not affected appreciably by dietary zinc level. In all tissues, 65Zn retention was drastically reduced with 1200 ppm added dietary zinc. Additional dietary zinc reduced 65Zn in muscle and heart but had little effect on liver and kidney 65Zn. The data indicate that rats have fairly effective homeostatic control mechanisms for tissue zinc below about 7200 ppm dietary zinc. Whereas, with dietary zinc up to about 1200 ppm, decreasing absorption is the main route of homeostatic control, above this level, more rapid zinc turnover rates and increasing endogenous zinc excretion appear to have major importance.


Plasma steroid concentrations in conscious and anesthetized rabbits.

The ovarian steroids, estrogen, androgen, and progestin, were measured in the peripheral plasma of adult female rabbits that were either conscious or anesthetized with sodium pentobarbital (nembutal) or halothane. Concentrations of estrogen, androgens, and progestin were determined before and at 10 and 45 min after systemic injection of either buffer or LH. In the controls androgen levels were significantly different between animals anesthetized with nembutal and halothane. However, the greatest treatment effect was noted in plasma progestin concentrations which were significantly elevated in halothane-anesthetized animals in comparison to the conscious and nembutal-anesthetized animals. Following LH, the androgen and progestin levels were significantly elevated over basal levels. Most likely the treatment effect observed in the controls was still present but was overridden by the increased release of steroids following gonadotrophin stimulation. This study suggests that halothane, in contrast to nembutal, does significantly elevate peripheral progestin and androgen levels.


Effect of intravenous C-terminal octapeptide of cholecystokinin and intraduodenal ricinoleic acid on contractile activity of the dog intestine.

Intraduodenal infusion of ricinoleic acid and iv bolus injection of the C-terminal octapeptide of cholecystokinin produce markedly similar alterations in the digestive contractile patterns of the GI tract of the unanesthetized dog. The brief, initial stimulation of contractile activity in the proximal small intestine following both procedures is mediated through a cholinergic mechanism. The stimulatory response is followed by an inhibition of digestive contractile activity of unknown origin. These observations suggest that possibility that the GI hormone, cholecystokinin, may mediate the intestinal motor response evoked by infusion of ricinoleic acid directly into the proximal small intestine.


Lipophilic and respiratory properties of NADH and succinate dehydrogenase sites in mitochondria from various tissues of the rat.

Mitochondria were isolated from heart, liver, kidney, spleen, and brain of the rat. With overall regard to both resting and activated respiratory velocities with either glutamate or succinate, as well as the respective degrees of respiratory control, kidney mitochondria were most efficient and spleen mitochondria least so. A probe of mitochondrial inner membrane lipophilicity with tetrabutylammonium bromide showed that NADH dehydrogenases from liver and heart were similar, as were also those from kidney and spleen. With the exception of brain, only small differences were observed in lipophilic properties of succinate dehydrogenases from the various other tissues. Variation in lipophilic characteristics of the two sites on the mitochondrial inner membranes could not be correlated with embryological origin of the tissue.


Effects of propranolol on renin release during chronic thoracic caval constriction or acute renal artery stenosis in dogs.

Dogs were given d,1-propranolol before and after thoracic inferior vena cava constriction (TIVCC) or renal artery constriction (RAC) to determine if the increase in plasma renin activity (PRA) and associated biological activity could be suppressed. Oral propranolol administration (240 mg twice daily) was begun at least 2 days prior to TIVCC in six dogs; heart rate was reduced from 133 to 95 beats/min but PRA did not change with propranolol administration. After TIVCC and during continued propranolol administration, daily renal sodium excretion fell from an average value of 50 to less than 3 mEq sodium/day and PRA was elevated two- to fourfold. With prolonged propranolol administration during TIVCC, PRA returned toward normal levels but renal sodium excretion remained low. At this time, hourly measurements of sodium excretion showed no change after a 240-mg oral dose or propranolol although very high plasma levels of propranolol were achieved; also, PRA was unchanged and low. The effects of RAC were studied before and during an intravenous propranolol infusion (0.2 mg/kg/hour) in conscious animals. Before propranolol administration, arterial pressure increased during RAC from 120 to 136 mm Hg and PRA doubled. Propranolol infusion lowered heart rate from 110 to 84 beats/min, but arterial pressure and PRA were not attentuated by propranolol during RAC. The data indicate that non-beta-adrenergic mechanisms are involved in renin release during TIVCC and RAC.


Effect of nonsuckling interval in the ether-induced release of immunoprecipitable prolactin in the plasma of the lactating rat.

The concentration of prolactin in the plasma of lactating rats increased from 24 to 74 ng/ml following acute ether stress as the length of the preceding period of nonsuckling diminished from 12 to 8 hr. In a second experiment the prolactin concentration increased from 24 to 79 to 104 ng/ml as the frequency of 10-min sucklings during a 12-hr period was altered from once at the end of the twelfth hr to once every 6 hr to once every 4 hr and the mothers then exposed to ether 12 hr after the last suckling. These results indicate that more frequent activation of the prolactin-releasing mechanism facilitates the subsequent release of prolactin in response to ether stress.


The inhibitory effect of vitamin E on desferrioxamine-induced iron excretion in rats.

The influence of vitamin E on the mobilization and excretion of storage iron induced by DF was studied in normal and iron-overloaded rats. Vitamin E administration in pharmacologic doses resulted in complete inhibition of the effect of DF on storage iron in iron-overloaded rats while no such effect could be demonstrated in rats with normal iron stores. The mechanism of the observed inhibition of DF action by vitamin E is at present unknown. Nevertheless this drug interaction has to be considered in view of ongoing therapeutic trials where both antioxidants and iron chelating drugs are administered simultaneously to thalassemic patients with transfusion induced iron overload.


Protective effects of cholestyramine in rats fed a low-fiber diet containing toxic doses of sodium cyclamate or amaranth.

Immature male rats were fed a purified, low-fiber diet containing massive doses of sodium cyclamate or amaranth (FD and C Red No. 2). Sodium cyclamate when incorporated at a 5% level in the purified, low-fiber diet resulted in toxic manifestations which were counteracted by the concurrent administration of the anion exchange resin cholestyramine at a 2 1/2% level in the diet. Other anion exchange resins were also active in this regard. Cholestyramine at a 2 1/2% level of supplementation was also active in counteracting the toxic effects induced by amaranth when the latter was incorporated at a 5% level in the purified, low-fiber diet.


Inhibitory effect of synthetic phospholipid vesicles containing cholesterol on the fertilizing ability of rabbit spermatozoa.

Suspensions of dimyristoyl and dipalmitoyl phosphatidylcholine vesicles bearing 10 to 40 (w/w)% cholesterol inhibited the fertilizing ability of uterine-capacitated rabbit spermatozoa at concentrations of 1 to 10 mg of lipid/ml. Recovery of fertilizing ability by treated sperm cells was observed following insemination into the uterus 5 to 6 hr before ovulation. Vesicles lacking the sterol were not inhibitory under the conditions employed. Suspensions of cholesterol (0.4 to 4 mg of sterol/ml) with out phospholipid, in contrast, inhibited fertilization. Implication of cholesterol in sperm decapacitation by seminal plasma membrane vesicles is discussed in terms of these results.


The effect of partial starvation and glucagon treatment on intestinal villus morphology and cell migration.

Male Sprague-Dawley rats were either treated with repeated ip injections of glucagon every 6 hr or partially starved. After 7 days of partial starvation or 5 days of glucagon injections, a time period shown previously to induce increased transport, all animals were sacrificed and a segment of jejunum was removed, fixed in formalin, sectioned, and dipped in Kodak NTB-2 liquid emulsion. After 8 weeks of exposure the autoradiographs were developed; assessments of villus height and crypt depth and measurements of length of the column of exposed grains were made in a calibrated microscope. The mean villus length in both semistarved and glucagon-treated groups was found to be significantly reduced (p less than 0.001) when compared to control animals. The crypt-to-villus ratio was found to be unaltered by either treatment modality. The rate of cell migration was diminished by both partial starvation and glucagon treatment, but only glucagon therapy was found to cause a significant (p less than 0.01) reduction in the rate of cell movement when compared to controls.


Influence of uridine-5-monophosphate on 3H-leucine incorporation into hippocampal neurons during learning.

The influence of UMP (injected intraventricularly) on the incorporation of 3H-leucine (injected intraperitoneally) was studied in rats using the microautoradiographic technique. Under the conditions of a brightness discrimination, the incorporation of labeled leucine into hippocampal neurons was significantly increased by UMP pretreatment, whereas under control conditions UMP caused only a tendency of increase without any statistical significance. It is suggested, that under learning conditions UMP substitution increases RNA synthesis, which would yield an enhanced protein synthesis.


Two types of habituation in chicks: differential dependence on cholinergic activity.

The role of cholinergic activity in habituation in chickens was tested using spontaneous alternation (SA) and reduction in response suppression to an auditory startle stimulus. While central reduction of cholinergic activity via atropine sulfate administration reduced SA and by inference, habituation, habituation to the tone was unimpaired, suppression decreasing with signal repetition even after a higher dose of atropine than that found effective in disrupting SA-indexed habituation. These findings confirmed an earlier suggested dissociation between habituation to externally produced stimuli e.g. startel stimuli, independent of cholinergic activity, and habituation to self=produced stimulation, e.g. exploration, spontaneous alternation, dependent on cholinergic functioning.


Effect of d-amphetamine, ethanol and genever on learning in the rat.

The effect of oral administration of d-amphetamine (5 mg/kg), ethanol (2.5 g/kg), genever (equivalent to 2.5 g/kg ethanol) and the combinations d-amphetamine-ethanol and d-amphetamine-genever was studied on learning in the rat, using a shuttle-box in 4 sessions at 24 hr intervals. Acquisition was significantly favored by all treatments, being more constant in the 4 sessions when combinations d-amphetamine-ethanol and d-amphetamine-genever were administered.


Effect of an angiotensin antagonist, Sar1-Ala8-angiotensin II on physiological thirst.

Initially it was shown that infusion of Sar1-Ala8-angiotensin II (P113) into the third ventricle (50-100 mug/ml at 1.1 ml/hr) effectively abolished the large water intake induced 1-2 min after beginning an intracarotid infusion of angiotensin II at 800 ng/min which causes an unphysiologically high concentration of angiotensin II in cerebral arterial blood. Infusion of P113 (50-100 mug/ml at 1.1 ml/hr) into the third brain ventricle for 20 min prior to and during presentation of water to sheep after 48 hr water deprivation did not reduce water intake. Water intake associated with rapid food intake or carotid artery infusion of hypertonic NaC1 was similarly unaffected by intraventricular administration of P113. While high concentrations of angiotensin II are dipsogenic in sheep, these results cast doubt on a contributory role for angiotensin II in thirst caused by water depletion or rapid food intake in the sheep.


Effect of scopolamine on the reactivity of the albino rat to footshock.

To determine if anticholergic drugs altered reactions to footshock, 9 female albino rats were tested for escape latencies following unsignaled presentations of footshock in a two-chambered shuttlebox. Different intensities of footshock (0, 0.04, 0.07, and 0.10 ma) were varied orthogonally with various doses of intraperitoneally injected scopolamine hydrobromide (0, 1.0, 4.0 and 16.0 mg/kg). Shock trials were randomly alternated with nonshock (pseudoshock) trials to estimate any drug-induced activity increase which might occur independently of any alteration in reactivity to aversive stimulation. Results indicated that scopolamine produced a significant increase in reactivity to footshock (i.e., shorter escape latencies) at near-threshold intensities as well as producing the expected increase in general activity.


Effect of aminooxyacetic acid on audiogenic seizure priming in C57BL/6J and SJL/J mice.

An attempt was made to determine the effects of genetic and temporal factors on the inhibitory action of aminooxyacetic acid on priming for audiogenic seizures. SJL/J and C57BL/6J mice were administered 20 mug/g of AOAA subcutaneously, employing either a 2 hr or 5 hr injection-prime interval, and either a 2 day or a 9 day prime-test interval. It was found that an inhibitory effect on priming occurred only in C57BL/6J mice; this effect was significant only for the 9 day groups, and was observed when wild running was used as the criterion for seizures, but not when clonic convulsion was the criterion. Effects of AOAA are discussed in relation to theories of seizure development through disuse supersensitivity, or by chemical actions on the GABA system.


Propranolol and skilled human performance.

In a double-blind crossover experiment 18 young men received on one occasion 6 doses of 40 mg propranolol and in the other placebo. Medication was given at 6 hour intervals. One hr after the last capsule was ingested subjects were measured with various physiological and behavioral tests. At the conclusion of testing mean plasma propranolol concentration was 67.6 ng/ml. Propranolol significantly reduced systolic blood pressure and heart rate. There was an increased variability on one behavioral measure but the results of other tests were not affected. The findings are discussed in terms of therapeutic use of this and other beta-adrenergic receptor blocking agents.


Physiological and biochemical concomitants of restraint stress in rats.

Restraint stress of 30 min increases plasma CS and lowers hypothalamic NE. Restraints of longer durations are associated with an attenuation of these changes. Daily repetitive restraint enhances the CS response on the second day and progressively diminishes it on subsequent days. Whole brain NE increases on the first day and decreases on Day 2 to 5. The CS response to acute restraint is similar in 5 different normotensive rat strains, but is enhanced in the genetically hypertensive SH rat, its normotensive backbreed WKY, and the DOCA hypertensive Sprague-Dawley rat. Comparison with other stressors (electric foot shock and novel environment) indicate that the responses to restraint are different at least in time course, if not qualitatively.


Effect of chlordiazepoxide on schedule-controlled responding and schedule-induced drinking.

Lever pressing of four rats was maintained under a multiple fixed ratio 80, fixed interval 2-min schedule of food presentation.  Water was concurrently available from a drinking tube. Overall rates of lever pressing were highest under the fixed ratio schedule and, for three rats, most drinking occurred during the pause preceding responding under the fixed interval schedule. Chlordiazepoxide increased the lower rates of lever pressing maintained under the fixed interval schedule but generally decreased the higher response rates under the fixed ratio schedule. The effects of chlordiazepoxide on schedule-induced licking also depended on  the extent to which this response occurred in each schedule component. Typically chlordiazepoxide produced relatively greater increases in the lower levels of licking and either increased less or decreased licking in that component where, under control conditions, this response was more extensive. Chlordiazepoxide also produced overall increases in the total amount of water consumed during the session. When the number of food pellets obtained during the experimental session was given all at one time in the home cage, the amount of water ingested over a period of time equivalent to the session duration was substantially less than that consumed during the experimental session. Chlordiazepoxide did not increase home cage water consumption under this condition.


Effects of amphetamine on short-term, protein-independent, memory in day-old chickens.

When the protein synthesis inhibitor cycloheximide (CXM) is administered just before or soon after a single learning trial, the formation of permanent memory is prevented in day-old chickens. In spite of the blockage of long-term memory, which occurs by 3 hr, Mark and Watts [14] have demonstrated a short-term memory which is independent of protein synthesis and which decays over the 3 hr period. D-amphetamine sulphate, administered subcutaneously (up to 2 hr) after learning to CXM pretreated chickens, held the memory at the level exhibited by the labile memory trace at the time of injection. This close relationship between the amount of labile memory and the time of injection was still apparent 24 hr after learning. These data suggest that, provided there is sufficient labile memory in existence at the time of administration, amphetamine maintains the trace which would otherwise decay and allows it subsequent consolidation into permanent memory at a time later than normal.


Effects of phenobarbital on saccharin and citric acid intake in fluid deprived rats.

Rats were adapted to a 23 hr fluid deprivation schedule. Every third day animals were offered either 0.125 percent Na saccharin or 0.2 percent citric acid solutions in place of water during the 1 hr drinking session. Sodium phenobarbital was administered subcutaneously, 40 mg/kg, 15 min prior to drinking. Results indicate that the drug increases saccharin and citric acid consumption following the injections. No decreases in intakes of saccharin and citric acid occurred on subsequent postdrug days and the amounts of fluid consumed on these days were comparable to the baseline predrug days intakes.


Testosterone and the sex difference in blood pressure in mice.

Blood pressure of adult male SWR/J mice is approximately 20 mm Hg higher than that of females. Castrating males at weaning eliminated this sex difference. Testosterone restored blood pressure of castrated mice to the level of the intact males within 10 days indicating a pressor effect of testosterone. Ovariectomy had no effect on blood pressure.


Exaggerated avoidance of novel stimulation in rats partially recovered from central norepinephrine damage.

Rats in which central norepinephrine lesions are made with 6-OHDA and a recovery period allowed show a behavioral syndrome distinct from controls, from rats with more extensive norepinephrine damage (lesioned with 6-OHDA, allowed to recover, and relesioned), and from rats with general depletion of serotonin (chronic PCPA). These rats administered central 6-OHDA injections and then allowed a recovery period rear less in open field than all other groups and are characterized by an exaggerated avoidance of novel visual stimulation in light onset and light escape tests. It is proposed that this reflects the hyperresponsivity of partially repaired, supersensitive norepinephrine circuitry to novel or intense stimulation.


Comparison in mice of the amnestic effects of cycloheximide and 6-hydroxydopamine in a one-trial passive avoidance task.

To test further the hypothesis that cycloheximide (CXM)-induced amnesia is due in part to its effects on the central adrenergic system, a comparison was made in mice of the effects of the antibiotic and of 6-hydroxydopamine (6-OHDA) on memory of a one-trial passive avoidance task. Both drugs produced anmesia 24 hr after training but unlike CXM, 6-OHDA had no effect on memory 20 min after training.


The specificity of the dipsogenic effect of angiotensin II.

The specificity of choice in drinking by sheep was examined when a cafeteria of water and of 900 mmol/1 solutions of NaCl and KCl was presented, during intracarotid infusion of angiotensin II (800-1200 ng/min) or 4M NaCl (1.6 ml/min), and following 48 hr of water deprivation or following Na depletion. Water was the fluid of predominant choice with angiotensin II, 4M NaCl infusion and water deprivation. The hypertonic NaCl was the clear choice of the Na deficient animals. With a cafeteria of 300 mmol/l solutions, there was no clear discrimination between NaCl and water with intracarotid angiotensin II infusion. A 2 choice study of taste preference for water or NaCl concentrations with free access indicated sheep elect to take more of higher NaCl concentrations than the rat, and that 300 mmol/1 NaCl is not less preferred than water in sheep. The data indicated, overall, that the dipsogenic effect of supraphysiological cerebral blood concentrations of angiotensin II is biased to water drinking when the choice is between water and 900 mM NaCl and KCl solutions. It does not induce any specific salt appetite.


Heat-escape behavior in the rat following intrahypothalamic injection of acetylcholine.

The effects of preoptic/anterior hypothalamic injections of acetylcholine on heat-escape behavior and hypothalamic temperature were investigated in unrestrained rats implanted with bilateral cannulae. Two types of responses were observed, either a fall in hypothalamic temperature coupled with an increase in behavioral responses to escape heat or a rise in hypothalamic temperature associated with little or no change in behavioral heat-escape responses. The fall in hypothalamic temperature observed in one group of rats was significant and was associated with a dose-dependent increase in heat-escape responding. The rise in hypothalamic temperature noted in the other group of rats was nonsignificant, and the associated behavioral responses were variable. Distinct anatomical differences in cannulae loci between the 2 groups were not apparent. It is concluded that acetylcholine activates the heat-dissipating control system of the rat hypothalamus and that the hyperthermic effects of acetylcholine are nonspecific.


Is the release of noradrenaline necessary for self-stimulation of the brain?

The hypothesis that a quantity of noradrenaline released contingently on every response made to obtain brain stimulation mediates the reward produced by the stimulation was tested. An alternative hypothesis is that reward is mediated by a different system, but that a steady activation of post-synaptic receptors by noradrenaline is necessary for normal behavior. The synthesis of noradrenaline was inhibited by disulfiran, and when lateral hypothalamic self-stimulation in the rat had ceased, alpha-adrenergic stimulants were injected intraventricularly (IC) or intraperitoneally (IP). The directly acting receptor stimulants oxymetazoline (0.9-250 mug IC), naphazoline (20-250 mug IC), and clonidine (0.75-3 mug IC, 0.037-3 mg/kg IP) did not restore self-stimulation, but the indirectly acting stimulants amphetamine (2 mg/kg IP), methylphenidate (3 mg/kg IP) and phenylephrine (15 mug IC) did not restore self-stimulation. In Experiments 2 and 3, in which either the functional noradrenaline pool was depleted with disulfiram and amphetamine, or the reserve noradrenaline pool was depleted with reserpine, the action of phenylephrine in restoring self-stimulation was shown to be indirect, probably by mobilizing a reserve pool of noradrenaline. Because only indirectly acting noradrenergic stimulants which facilitate the release of noradrenaline restores self-stimulation, it is concluded that noradrenaline must be released contingent on every response for self-stimulation to occur. Whether this released noradrenaline mediates the reward or has some other function associated with bar-pressing behavior remains to be shown.


Postnatal behavioral effects in mice after prenatal exposure to methylmercury.

CFW mice were injected with methylmercury hydroxide (1, 2, 3, 5 or 10 mg/kg as mercury) on Day 8 of gestation. Mice treated with 3, 5 or 10 mg/kg averaged 1/3 fewer pups than controls. Pups from these treated animals weighed less than controls and the weight differences persisted through weaning but were no longer significant at 56 days of age. Mice exposed to methylmercury in utero showed significant differences from controls in their behavior in a 2-way active avoidance shuttle box and in a punishment situation but not when tested in an open field, a water escape runaway or a conditioned suppression paradigm. Neither the mothers nor progeny of the mice exposed prenatally to methylmercury showed bahavioral deficits.


The role of locomotion in conditioning methylphenidate-induced locomotor activity.

This experiment determined whether overt performance of the entire response (actual running) was necessary for the conditioning of methylphenidate-induced locomotor activity (wheel-running) in guinea pigs. Four guinea pigs were given daily injections of 2.5 mg/kg methylphenidate and were allowed to run in activity wheels; 4 other guinea pigs were given methylphenidate and were placed in locked activity wheels; a third group of 4 guinea pigs were administered saline and allowed to locomote; a fourth group of 4 guinea pigs received saline injections and were placed in locked activity wheels. After 12 days of injection, all animals were given saline injections on the 9 subsequent days and allowed to run freely in the wheels. The 2 groups which had received methylphenidate showed more locomotor activity than the saline injected animals but were not distinguishable from each other on the basis of prior opportunity to engage in locomotor activity. These results were interpreted to indicate that (a) increased methylphenidate-induced locomotor activity may be conditioned with repeated administration of the drug, and (b) actual running is not essential for the conditioning of drug-induced wheel-running.


Blockade of the behavioral effects of 5-HTP by the decarboxylase inhibitor Ro 4-4602.

Twenty male rats were trained to press a bar on a fixed-ratio (FR 32) schedule of water reinforcement. The behavioral effects of 5-HTP (50 mg/kg) were studied following pretreatment with small (50 mg/kg) and large (400 mg/kg) doses of the decarboxylase inhibitor Ro 4-4602. It was found that both doses of the pretreatment agent blocked the disruptive effects of 5-HTP. This result suggests that at least some of the effects of 5-HTP may be mediated peripherally.


Behavioral effects of chronic lead ingestion on laboratory rats.

Rats continuously exposed to lead acetate solutions were tested on a visual discrimination reversal problem, on the open field and in 2 shuttle avoidance situations. High lead intake produced slower acquisition of the visual discrimination problem but had no effect on reversal performance. High lead intake reduced activity on the open field and improved performance on both shuttle avoidance problems. Results are interpreted to indicate that the effects produced by exposure to lead may involve an increase in responsiveness to aversive situations.


Effects of nicotine on the exploratory locomotion patterns of female Roman high- and low-avoidance rats.

Utilizing an automated, Dashiell-type hexagonal maze, it was demonstrated that RHA rats: 1) were more active, 2) reversed direction more often, 3) entered radial (blind) alleys less often, and 4) displayed shorter latencies than did RLA rats. Direction reversals (U-turns) tended to increase from day to day with the RHA rats, whereas the opposite was true for the RLA rats. Nicotine injections (0.2 mg/kg) increased activity and the number of U-turns, shortened the latencies and lessened the likelihood of entering radial alleys for both strains. The RHA rats were more sensitive to nicotine than were the RLA rats in all of these measurements, which varied, depending upon alley length and structural complexity, among the maze configurations.


Cycloheximide and passive avoidance memory in mice: time-response, dose-response and short-term memory.

The greatest loss of memory shown by mice 24 hr after learning was found to occur with cycloheximide (CXM) (120 mg/kg) administered subcutaneously 30 min before training. With injection at this time the extent of the amnesia was dose dependent (30-150 mg/kg) and the resultant amnesia was found to be relatively constant when tested at 1, 7 or 14 days. An attempt was made to follow the development of this amnesia with 100 and 120 mg/kg CXM. However, the saline controls showed an unexpectedly low avoidance 6 hr after training. This was interpreted as a possible interaction between the stress of the injection and the 6 hr interval. An experiment designed to test this possibility showed that mice injected with 0.1 ml of 1% lignocaine gave high avoidance at 6 hr but mice receiving only a needle puncture of the skin gave performances similar to mice receiving saline injections. It was felt that these findings cast doubt on the usefulness of the passive avoidance task in the assessment of drug action on short term memory.


Effect of ether, chloroform and carbon dioxide on monoamine inactivation.

To determine if anaesthetic agents alter monoamine inactivation, we exposed tissue homogenates (liver, kidney and brain) from mice and rabbits to ether and chloroform vapors and carbon dioxide gas. These anaesthetic agents inhibited monoamine oxidase (MAO) activity against typtamine and serotonin. Concentrations of anaesthetic agents that are achieved in the plasma of man during general anaesthesia caused a 27% (ether) and 49% (chloroform) reduction in mouse liver MAO; higher concentrations caused a 95% inhibition mouse or rabbit liver MAO. Kinetic analysis with tryptamine as substrate indicate that ether and chloroform are noncompetitive, reversible MAO inhibitors that preferentially inhibit Type B MAO. Ether and chloroform cause noncompetitive inhibition of serotonin oxidation by mouse liver MAO and competitive inhibition of serotonin oxidation by mouse brain and kidney MAO. Ether or chloroform did not alter catechol-O-methyltransferase activity from tissues of mice. Isolated blood platelets (rabbit and human) were used as a model system for neuronal uptake. Ether caused an irreversible inhibition of serotonin uptake by platelets.


Acute intravenous infusion in freely moving rats through the sagittal and transverse sinuses.

A technique is described which allows drugs to be injected intravenously using the junction of the sagittal and transverse sinuses as the point of entry into the venous system. The procedure is rapid and uses conventional stereotaxic techniques. Subsequent restraint of movement during drug infusion is minimal. Using this method, 15 mug/kg d-lysergic acid diethylamide produced an increase in acoustic startle amplitide within about 1-2 min which lasted for about 25 min.


Hyperthermia following self-stimulation of the median raphe in the rat.

Electrical self-stimulation (SS) in the median raphé of the rat but not in the locus coeruleus resulted in a dramatic rise of body temperature. This hyperthermia was facilitated by pretreatment with a inhibitor of serotonin uptake. The functional significance of the hyperthermia elicited by stimulation of the media raphé was discussed on the basis of the relationship between SS and primary reinforcers.


Effect of combined reserpine and ECS on electroshock seizure thresholds in mice.

Recent evidence has suggested that electroshock seizure threshold is correlated with levels of brain biogenic amines. Reserpine, a drug that depletes serotonin and norepinephrine, has been shown to decrease seizure thresholds. ECS treatment has been shown to increase amine levels as well as seizure thresholds. Combined reserpine and ECS have been shown to produce an intermediate level of serotonin and norepinephrine, but seizure threshold data for this group is absent. It was the purpose of this study to examine the seizure thresholds for combined treatment and compare them with groups treated with reserpine alone, ECS alone, and a placebo control group. The results suggest that, if only maximal seizures are considered, the seizure threshold is lowest for the reserpine and highest for the ECS alone or control groups, with the combined treatment group falling intermediate. If both minimal and maximal seizures are considered, the reserpine and combined treatment groups do not differ from one another, but do show a lower threshold as compared to ECS or control groups.


A method to study short-term memory (STM) in the goldfish.

Twenty-one common goldfish (13-15.5 cm long) were randomly divided into alcohol (A) and nonalcohol (NA) groups and were trained in an alcohol solution of 400 mg/100 ml or in water, respectively. All alcohol fish were placed in an alcohol solution of 400 mg/100 ml for 3 hr before training in the same alcohol concentration. Fish were trained on a position discrimination task for 2 consecutive days. The door used for training was that opposite to each fish's spontaneous preference. Savings in relearning on Day 2 was taken as a measure of long term memory strength. Only fish which reached criterion on both days were immediately given 10 forced reversal trails in the opposite direction (i.e., a fish trained on right door was forced to choose the left door.) A and NA subjects were then tested after a 5 min (STM) delay, respectively, in a free choice situation for 10 trails (i.e., neither door was blocked). The results suggest that alcohol facilitates the STM of the forced reversal information.


Effect of dimethylpolysiloxane fluid on the stability and dissolution of prednisolone.

The physicochemical effects of a dimethylpolysiloxane fluid as a vehicle for prednisolone on its stability and dissolution pattern were evaluated. No detectable degradation of prednisolone was noted during 8 weeks of storage at 4, 26 and 45 degressC. The release rate of prednisolone from its suspension in dimethylpolysiloxane was lower than that from the aqueous suspension. However, the amount of prednisolone released in 30 min from the aqueous suspension was only about 5.5% greater than that released from its suspension in the silicone fluid.


Verruculogen: a new substance for decreasing of GABA levels in CNS.

In our previous work we examined the mechanism of action of the new tremorogenic substance verruculogen isolated by Cole and coworkers. Examining the effect of various substances with known mechanisms of action on verruculogen-induced tremor, we concluded that this tremor was probably related to decrease of GABA levels in CNS. In order to further define the mechanisms of action of verruculogen, we determined brain GABA levels in animals in which tremor was produced by verruculogen administration. Verruculogen administration produced a decrease in GABA levels in mouse CNS. This finding substantiates our earlier suggestion that verruculogen-induced tremor is mediated by a loss of inhibitory GABA function.


Comparative study of the effect of atropine, P2AM, and Buscopan. Total belladonna and hyoscyamus alkaloids on parathion poisoning.

Among the available antidotes used against parathion poisoning, atropine and Buscopan are tolerated in relatively high doses by rats. Hyoscine (in very small doses), T. Bel. Alk. and T. Hyosc. Alk. (better results in small doses, also for dogs), P2AM (of superior antimuscarine action) are redommended with each of the preceding drugs than either alone or in combination with Buscopan.


Action of naloxone on the interferon-lowering activity of morphine in the mouse.

The serum titer of interferon produced by polyinosinic:polycytidylic acid (poly I:C) was studied in mice following subcutaneous injections of either morphine alone, naloxone alone, morphine and naloxone together, morphine preceded by naloxone, naloxone preceded by morphine, or a sequence of injections of naloxone, morphine, and naloxone again. Poly I:C injected without the other drugs present served as the control. Both morphine and naloxone produced a significant decrease in the ability of the mice to increase the serum titer of interferon in response to poly I:C. Naloxone appeared to function as an antagonist to morphine when administered following the morphine injection, but not when injected before or simultaneously with the opiate. When naloxone was injected both before and following the morphine injection, results were interpreted to indicate the possibility that naloxone could function as both an agonist and antagonist under this condition.


Characteristics of histamine disposition in vascular smooth muscle.

This study has examined uptake, efflux and metabolism of 14C-histamine by vascular smooth muscle. 14C space in aortae reached 4.3 +/- 0.14 ml/g (mean +/- SE) after 1 h exposure to 14C-histamine (2 muM) in Tyrode's solution. Aminoguanidine (10(-5) M) and non-radioactive histamine (10(-4) and 10(-3) M) significantly reduced 14C space. Efflux experiments were performed on aortic strips exposed to 14C-histamine for 1 h. The rate of loss of radioactivity was not enhanced by nonradioactive histamine or compound 48/80. It appears that 14C-histamine was not accumulated and bound in mast cells in this tissue. After 1 h exposure to 14C-histamine, labeled material was extracted from tissues for identification of metabolites by paper chromatography. About 40% of the label was 14C-histamine, and the remainder was primarily imidazole acetic acid. After exposure to aminoguanidine, an inhibitor of diamine oxidase, about 80% of the label was 14C-histamine. These data suggest that oxidative deamination is the primary catabolic route for histamine in rabbit aorta.


Effect of adrenergic neuron inhibitors on the vascular response to sympathetic nerve stimulation.

In anesthetized cats, the lumbar sympathetic trunk was stimulated, and the responses of the resistance and capacitance vessels of the hindlimb were recorded (by resistography and plethysmography, respectively). The drugs used were reserpine, methyldopa and bretylium tosylate. It was found that reserpine and methyldopa inhibit the response of the resistance vessels to a greater extent than that of the capacitance vessels, while bretylium tosylate has a greater effect on the transmission of constrictor impulses to the capacitance vessels. Reserpine mainly suppresses responses to low-frequency stimulation and bretylium tosylate--those to high-frequency stimulation, while methyldopa affects them to the same degree at all frequencies.


Interactions between antimigraine drugs and a high affinity uptake and storage mechanism for 5-hydroxytryptamine.

Rabbit hearts removed 3H-5-hydroxytryptamine (3H-5-HT) from a perfusion concentration of 2.6 X 10(-9) g/ml. 15.8% of the extractable cardiac total radioactivity consisted of metabolites, mainly 5-hydroxyindoleacetic acid, and metabolism appeared in the perfusion fluid during the course of the perfusion. Ergotamine tartrate (1.0 X 10(-6) g/ml) caused a small increase in 3H-5-HT uptake by the heart. Methysergide bimaleate (1.0 X 10(-6) g/ml) slowed the appearance of metabolites in the perfusion fluid. Because of the high concentrations required, neither observation seems likely to be of clinical significance to migraine. The results do, however, suggest that the frequently observed sensitisation of tissues to 5-HT by ergotamine and methysergide is not the result of inhibition of its tissue uptake.


Anesthetic action of methyleugenol and other eugenol derivatives.

A comparative study of four natural eugenol compounds found in the volatile oil fraction of Myristica fragans, namely eugenol (E), methyleugenol (ME), isoeugenol and methylisoeugenol, was carried out in mice. Using a mixture of saline + tween-80 to suspend the compounds and the intraperitoneal route, ME revealed to be the most active and the less toxic in inducing the loss of the righting reflex. ME was further compared with pentobarbital and with the synthetic E derivative, propanidid, using the intraperitoneal route in rats. ME anesthetized the rats more rapidly than pentobarbital; however, the duration of anesthesia was the same for both drugs. Propanidid was not active when injected through the intraperitoneal route. Rats under ME anesthesia could be more easily operated, showed less cyanosis, and recovered better than those under pentobarbital. When injected intravenously in rabbits, ME and propanidid showed equivalent anesthetic effects. Daily intraperitoneal injections of ME in rats and mice for up to 42 days, showed that the drug was not toxic and that the animals became more sensitive to the anesthetic action with repeating the injections. Similarly to pentobarbital, ME induced large amounts of slow wave activity in EEG of rats and did not change the total brain levels of dopamine, norepinephrine, and 5-hydroxytryptamine.


Influence of some antirheumatic drugs and cytostatics on urinary enzyme level.

In experiments with rats, the influence of the treatment with sodium salicylate (350 mg/kg), phenylbutazone (100 mg/kg), cyclophosphamide (5 mg/kg), 6-mercaptopurine (25 mg/kg) and D-penicillamine (50 mg/kg), on urinary lactate dehydrogenase, leucine aminopeptidase and alanine aminopeptidase was investigated. All these drugs caused an increase in the enzyme levels in urine. In the case of sodium salicylate, the increase occurred only after the first administration of the drug; phenylbutazone caused a gradual increase of the enzymes. Cytostatic drugs caused an increase in the level of the investigated enzymes in urine with a maximum after 1 week of treatment.


A method of X-ray attenuation analysis for approximating the intensity distribution at its point of origin of bremsstrahlung excited in a thick target by incident electrons of constant medium energy.

A computer-aided method of analysis of the attenuation by known materials of the exposure rate of a narrow beam of X-radiation generated by a constant medium potential at a thick smooth plane target is described. On the assumption that the average loss of energy of initially monoenergetic electrons is given by the Thomson-Whiddington relation, expressions are derived for the differential intensity of radiation leaving the surface of a solid plane target for a number of analytical approximations to the intensity distribution of the bremsstrahlung at its point of origin within the target. Particular forms of these approximations have been determined which yield attenuation curves closely matching those experimentally determined by Thoraeus for constant exciting potentials of 50, 60, 80 and 100 kV. They are found to be generally consistent with theoretical expectation and the few direct measurements available.


Specification and additivity of unsharpness in diagnostic radiology.

Definitions are proposed of line spread and point spread coefficients which may be used to quantify the degree of unsharpness in a radiographic image. Where there are several independent causes of unsharpness the squares of the spread coefficients are additive.


The construction and use of nomograms for cerebral blood flow calculation using a 133Xe inhalation technique.

Measurement of cerebral blood flow (CBF) using a 133Xe inhalation technique requires monitoring the clearance rate of the radioisotope from the head using externally situated detectors and also from arterial blood using a detector to monitor the expired air activity. The end-tidal concentration function is assumed to be proportional to the arterial concentration function and this has to be deconvoluted from the clearance functions obtained from the head to enable CBF to be calculated. A digital computer is generally considered to be essential for this. In this paper a procedure using three-dimensional nomograms is derived and tested. It is shown that results obtained using the nomograms do not differ significantly from results obtained using a full deconvolution procedure, and so it is not essential to use a computer to calculate CBF by the inhalation technique.


The energy response of LiF, film and a chemical dosemeter to high energy photons and electrons.

The physical responses of LiF, film and a chemical dosemeter in high energy photon and electron beams has been studied. It is shown that the response for film and the chemical dosemeter does not change significantly up to 42 MeV, while for LiF it decreases by about 10%. Analysis of calculations and measurements showed that this decrease could not be explained by existing theories.


Thermometry of the surface of human skin. A study on a model using thermocouples, thermistors, thermovision and thermodyes.

The temperature of the surface of a model of human skin is measured using a recently developed probe to house a thermocouple or thermistor. The results are compared with thermovision and thermodye measurements. The effect on skin temperature of hot and cold vessels at various depths is investigated.


Variables in recording motor conduction of the radial nerve.

Motor conduction examinations of the right radial nerve were performed on 25 healthy students. The purposes of this study were to determine the optimum position for placement of the active recording electrode, to determine the optimum position of the elbow during conduction examinations, and to report normal values for radial motor nerve characteristics. The radial nerve was stimulated at the supraclavicular notch, axilla, lateral surface of the brachium, and over the middle third of the forearm. The evoked responses were recorded from the abductor pollicis longus or the extensor pollicis brevis. The optimum site for placement of the active recording electrode was found over the medial aspect of the abductor pollicis longus or the extensor pollicis brevis and at a point that represents 28 percent of the forearm length. The optimum position for the elbow was full extension. The distal latency of 2.6 msec, the velocity of the brachium-forearm segment of 50 meters per second, and amplitude of muscle action potentials of 4.0 mv may serve as the limits of normal values for motor conduction of the radial nerve.


Electromyographic feedback to improve ankle dorsiflexion, wrist extension, and hand grasp.

Electromyographic feedback was used to train a patient with hemiplegia in the functional use of the muscles of his right upper and lower limbs. The patient trained with the therapist over a period of two and one-half months, engaging in exercises for ankle dorsiflexion, wrist extension, and hand grasp twice a week for one to one and one-half hours. Feedback was recorded with surface electrodes placed over the extensor surface of the forearm and the tibialis anterior; the electromyographic activity was displayed on a meter. After training, muscle control proved functional for walking, handwriting, and daily self-care activities.


Guidelines for meetings.

The major purpose of a meeting is to make decisions. The most basic and important elements of conducting a meeting, preparing motions for consideration, and recording the decisions are presented. The use of the guidelines for more or less formal meetings is discussed.


A congenital band about the pelvis. Case report with a 24-year postoperative follow-up.

A patient with a congenital band about the pelvis is presented. She was operated on in her early years. Photographs document the result during a 24-year follow-up.


Ski pole thumb injury.

Disabling injuries can occur in the area of the MP joint of the thumb when a skier falls against the planted ski pole while holding the ski strap in the usual fashion. This is presently the most common ski injury of the upper extremity. It is important to determine if instability has resulted, because there may be disruption of the ulnar aspect of joint capsule as well as of the extensoradductor hood mechanism. If this has occurred, it is immediately to prevent the development of the chronic "gamekeeper's thumb."


Gamekeeper's thumb.

Gamekeeper's thumb is due to complete rupture of the ulnar collateral ligament; it should be clinically differentiated from incomplete rupture. Methods of diagnosis and treatment of gamekeeper's thumb are described. The results in 10 cases of gamekeeper's thumb treated by surgery, with more than a one-year follow-up are evaluated.


Relative hypoxemia during rhytidoplasty.

The results of blood gas analyses in 24 patients who had a rhytidoplasty under local anesthesia indicated that a moderate degree of hypoxemia can be elicited in these patients when they have had standard doses of the usual sedatives. While the acid-base abnormalities were generally corrected spontaneously, the extent of the hypoxemia can be aggravated further by the additional use of diazepam during the operation. Therefore, over-sedation of such a patient during the operation, without a secured airway, must be avoided. Additionally, we recommend deep breathing at frequent intervals, with or without supplemental oxygen through a high flow system.


Blood gas and hemodynamic effects of sedatives and analgesics when used as a supplement to local anesthesia in plastic surgery.

In 20 patients undergoing a rhinoplasty or rhytidectomy under local anesthesia combined with intravenous sedatives and hypnotics, fairly satisfactory operating conditions were obtained. This technique was associated with respiratory depression and hypoxia, however, with statistically significant elevations in the arterial carbon dioxide tensions, and depressions in the arterial oxygen tensions. We now advocate the routine use of supplement oxygen and periodic deep breathing during the operation, and in the immediate postoperative period. We will continue to advise the use of general anesthesia in patients with cardiopulmonary disease. The mental detachment and inability to articulate discomfort during the procedure are major disadvantages to the use of fentanyl and droperidol in these patients.


Hidradenitis suppurativa of the groin, treated by excision and spontaneous healing.

A simplified approach to the surgical treatment of hidradenitis supprativa of the groin and perineum is presented. All tissue is excised down to the fascia, and the wound is allowed to granulate and epithelialize spontaneously. The advantage of the procedure are (1) a simple surgical technique, (2) easier postoperative care, (3) full and early ambulation, (4) no donor sites, (5) no losses of skin grafts, (6) early discharge from the hospital, and (7) early return to work.


Congenital giant nevi: clinical and pathological considerations.

A clinical and pathological review of 67 cases of congenital giant nevi and of 5 cases of malignant transformation in congenital giant nevi brings out the following. 1. The lesions should be regarded as premalignant. 2. An aggressive approach is advocated to remove the lesion before school age. 3. Staged excisions, combined with skin grafting and/or local rotation flaps, are advocated. 4. Any nodularity or ulceration developing within a congenital giant nevus should be regarded as an ominous sign. 5. A long-term follow-up is necessary in those patients having subtotal excisions.


Submucous cleft palate.

We review 97 cases of SMCP, 79 of which were operated. The comparative results are presented. For those requiring surgery (i.e. those having hypernasality), it has been our experience that the use of a pharyngeal flap, alone or combined with a palatoplasty, is productive of better speech results than is a palatoplasty alone.


Surgical cure of chronic paronychia by eponychial marsupialization.

A simple surgical procedure is presented which has been effective in curing the troublesome chronic paronychia. The anatomy and pathophysiology of this condition are discussed briefly.


The superficial musculo-aponeurotic system (SMAS) in the parotid and cheek area.

We have investigated the superficial musculo-aponeurotic system (SMAS) in the parotid and cheek areas by anatomical dissections, by radiographs, and by histological sections. The SMAS may be helpful in corrective surgery for facial palsy and during face lifting operations if a retrofascial approach is used. This procedure, safe in the parotid area, can become dangerous in the area anterior to the parotid gland.


A survey of social inadequacy among psychiatric outpatients.

An investigation into the extent and nature of social inadequacy among outpatients diagnosed as neuroses and personality disorders was undertaken on patients aged 18-49 attending one clinic over a six-month period. A feature of this survey was that each patient took part in a standard social interaction test, and their performance was assessed by two psychologists. A relatively high proportion of patients, one in six on the most conservative estimate, and probably over one in four, were judged by psychologists and psychiatrists to be socially inadequate, and the results showed a clear pattern of behavioural, social and personality factors associated with these judgements. Implications for assessment and treatment are discussed.


An investigation of psychological factors involved in the predisposition to auditory hallucinations.

Previous research by the author (Slade, 1972, 1973) and others has suggested that psychological stress plays an important role in triggering off the experience of auditory hallucinations. Clearly, however, predispositional factors are involved as well. The present study is an attempt to investigate some of the psychological factors which may predispose the individual to such experiences. A battery of tests involving cognitive, personality and mental imagery variables and the verbal transformation effect was administered to two small groups of psychotic patients differing only in respect of a history of auditory hallucinations and a normal control group. The main conclusion was that the results lend direct support to the proposition of Mintz & Alpert (1972) that a combination of vivid mental imagery and poor reality-testing in the auditory modality provides the basic predisposition for the experience of auditory hallucinations.


Psychoneurotic disturbance and drug-taking in Borstal boys.

Their own accounts of their use of drugs, together with a detailed description of psychiatric history and present mental state, were obtained from a sample of institutionalized delinquents, Subjects reporting extensive involvement in drug abuse were found to be disturbed on a number of psychiatric variables; however, those reporting some limited abuse were less disturbed than subjects reporting no experience of drug taking. The results and their implications are discussed.


Urinary free cortisol excretion in depression.

Urinary free cortisol (UFC) excretion was determined in 60 depressed inpatients and in 35 psychiatric inpatients with other disorders. The depressed patients had high daily UFC values, while the other patients excreted normal amounts. Over 40% of the depressed patients had UFC excretions in the range seen in Cushing's disease, while only 6% of the other patients excreted such high amounts of cortisol. Age and sex differences did not account for the results. Among the depressed patients those with depressive neuroses excreted less than unipolar or bipolar depressives. Following treatment, more normal UFC excretion was found in depressed patients. The estimation of UFC and its clinical utility are discussed in detail. UFC determination is a simple and informative indicator of adrenal cortical activation and its application to psychoendocrine studies is recommended.


Absorption of lithium following administration of slow-release and conventional preparations.

The plasma lithium levels of 18 subjects receiving one standard and two slow-release preparations of lithium carbonate were measured at frequent intervals during the 24 hours following oral ingestion of a single dose of the drug. Although the slow-release tablets showed slow-release in vitro, this was not so in vivo. One slow-release preparation, in particular, was ineffectively absorbed by some subjects. There was no difference in the rate of absorption and excretion between the other slow-release product and the standard BP preparation. The implications of the results are discussed.


The endogenous--neurotic distinction as a predictor of response to antidepressant drugs.

An inverse factor analysis of 880 depressed inpatients on 33 endogenous-neurotic variables yielded four patient types. Type 3 resembled the endogenous depressions and Type 2 the neurotic depressions. Type 3 patients responded well to both imipramine and chlorpromazine and did poorly on a placebo. Type 2 patients showed the greatest overall improvement at three weeks irrespective of treatment received, including a placebo.


The prevalence of early childhood autism: comparison of administrative and epidemiological studies.

The results of surveys and inquiries to identify autistic children, carried out in England and Wales, the U.S.A. and Denmark, are compared. Three studies, in each of which either a total population of children or a wide range of handicapped children was screened, using case-note inspection and interviews, all estimated the prevalence of the autistic syndrome to be between four and five children per 10,000 aged under 15 years. Inquiries that counted diagnosed cases only or that relied upon local authority records produced much lower prevalence rates for the autistic syndrome. The reasons for this are examined, and the implications for prevalence studies of handicapping conditions are discussed.


Cardiovascular responses to avoidance conditioning in the dog: effects of beta adrenergic blockade.

Five laboratory dogs were trained to press a response panel to postpone shocks during 1-hr free-operant avoidance conditioning sessions. In addition, each dog was confined in the experimental environment for 1 hr immediately prior to each avoidance session. During these 2-hr sessions, blood pressure and heart rate were monitored continuously from indwelling catheters. After repeated exposure to the schedule, the onset of the avoidance contingency elicited acute increases in systolic and diastolic pressure and heart rate, which were maintained throughout the session. During the preavoidance interval, systolic and diastolic pressure increased gradually while heart rate decreased. Blockade of beta adrenergic receptor activity in these behaviorally-trained dogs by infusions of propranolol was associated with a significant attenuation of the tachycardia normally maintained during avoidance. Beta blockade did not prevent the rise in blood pressure or fall in heart rate during preavoidance. The results are consistent with the view that the cardiovascular pattern sustained during avoidance is mediated by activation of the sympathetic nervous system, but that the progressive change in cardiovascular activity during preavoidance intervals is mediated by other than sympathetic influences.


Emotionally induced decreases in pulmonary flow rates in asthmatic children.

This study found that vividly remembered incidents of intense anger and similarly recalled fear decreased 1-sec forced expiratory flow rates (FEV1)in 35 male and 25 female chronic asthmatic children who had no psychopathology. FEV1 increased with relaxation. Changes in FEV1 following anger correlated with changes following fear as highly as the reliabilities of the responses permitted, although anger produced a greater decrease than fear. FEV1 decrease following anger and fear correlated with FEV1 increase due to relaxation. The amount of change in each of the three conditions correlated with history of emotionally precipitated asthma. This pattern was interpreted to mean that the same phenomenon underlies emotional-bronchoconstriction, relaxation-bronchodilitation, and emotionally triggered asthma. No relationship was found between degree of allergic sensitivity (atopy) and FEV1 changes in any of the three conditions nor did atopy correlate with history of emotionally triggered asthma. These results do not support the view that psychological and allergic factors are inversely related, alternative causes of asthma.


Classically conditioned changes of blood glucose level.

This paper reviews the literature dealing with classically conditioned changes of blood glucose level. When conditioning procedures are employed, the repeated administration of large amounts of insulin, or of glucose, leads to a conditioned decrease of blood glucose whereas the repeated administration of smaller amounts of insulin leads to a conditioned increase of glucose. These responses are interpreted as instances of reflex compensation by the central nervous system for rapid alterations of glucose availability. Instances of more naturally occurring changes of glucose levels, which appear to be under the control of the nervous system and to be conditionable, are also discussed. A model that accounts for the observed responses has been formulated and is presented.


Hepatocytic hamartoma (focal nodular hyperplasia of the liver): angiographic aspects.

A case of 'benign tumor' of the liver (hepatocytic hamartoma), in a 24-year-old female is presented. The angiographic aspects are stressed and the radiological disgnosis is discussed in the light of similar observations reported in the recent medical literature.


Preoperative localization of enlarged parathyroid glands: indication for and criteria in the evaluation of venous sampling.

The results of 45 non-selective and 26 selective preoperative localization examinations in patients with primary hyperparathyroidism are compared with the findings at operation. First operations are distinguished from re-operations. On the basis of personal observations and data from the literature, indications for preoperative localization examination are established. Criteria are formulated for the evaluation of the result of preoperative localization examination as correct, erroneous or inconclusive.


Female gonadal exposure dose in routine diagnostic radiology.

Measurements of gonad doses received by female patients during routine roentgenology are presented. LiF dosemeters were used to measure the exposure doses in the vagina. With the aid  of phantom studies, the ovary doses were calculated from the doses determined in patients. Their relationships to skin doses are shown. The results are tabulated. A comparison with results by other authors is given.


The natural history of coronary artery stenosis. A longitudinal angiographic assessment.

Comparison of sequential large film coronary angiograms was performed for 58 patients with coronary artery disease, and no coronary surgery, to determine the relationship between the location, type, and degree of stenoses and their tendency to progress. Of 230 stenoses, 76 (33%) showed progression and 154 (67%) remained stable on the follow-up studies. Progression occurred in 38 (66%) patients. A statistically significant higher tendency to progress was found with tubular stenosis with ulcerating plaques (100%) and stenoses with collateral circulation (58%). A significant linear trend for progression was also found with the increasing number of risk factors of coronary disease. The above-average progression tendency of stenoses of the right coronary artery, tubular irregular stenoses, and Grade 2 stenoses, was not statistically significant.


Spontaneously and pharmacologically provoked coronary arterial spasm in Prinzmetal variant angina.

Eleven of 21 consecutive patients with Prinzmetal angina (PMA) exhibited no significant fixed stenoses of the coronary arteries. Spontaneous coronary arterial spasm was demonstrated in 3 patients. Ergonovine maleate produced near-total occlusion of a major vessel in 3 of 4 other patients with PMA, but did not provoke spasm in 10 without PMA. The current study documents spasm as the mechanism of myocardial ischemia in some patients with normal coronary arteries and provides initial and favorable diagnostic results with provocative pharmacoangiography in this entity.


Collateral circulation to an ischemic kidney.

A review of 301 consecutive abdominal arteriograms given to patients suspected of having occlusive arterial diseases was conducted. In 99 patients, 35% or more stenosis of the renal artery was demonstrated; of these, 40 showed demonstrable collaterals to the ischemic kidney. The adrenal and lumbar arteries contributed four times more frequently than the periureteric arteries to the collateral circulation. Characteristic ureteral notching from the periureteric artery collateral was noted in only 50% of the cases. Intrarenal collaterals were observed and appeared to contribute to the preservation of the size and function of the affected kidney.


Page kidney: an unusual cause of hypertension.

A case of classical Page kidney with emphasis on radiographic findings is presented. Onset of hypertension following trauma associated with angiographic findings of attenuation, splaying and stretching of the intrarenal vessels on the arterial phase with a definite delay in transit time through the parenchyma and a non-homogeneous nephrogram should make the diagnosis of Page kidney or constricting subcapsular mass the most logical consideration.


Transcatheter embolization of the spleen for control of splenic hemorrhage and in situ splenectomy: an experimental study using silicone spheres.

Silicone spheres were used for the transcatheter arterial embolization of dogs. This material successfully stops splenic hemorrhage in the lacerated organ, and also reduces spleen size. Use of silicone emboli to produce in situ splenectomy is not associated with morbidity or mortality in dogs. The authors discuss the value of using these methods in treating the high-surgical-risk patient.


Unusual calcification in mixed papillary and follicular carcinoma of the thyroid gland.

An unusual egg-shell calcification was found in the thyroid gland on a routine radiograph. The 99mTc-pertechnetate thyroid image showed a cold nodule in the inferior pole of the left lobe which proved to be mixed papillary-follicular carcinoma. There was no characteristic pattern of calcification in the thyroid gland which would permit precise diagnosis of cancer; however, psammomatous calcification frequently occurs in papillary carcinoma of the thyroid.


Selective catheterization of the pancreatic vein for radioimmunoassay in glucagon-secreting carcinoma of the pancreas.

A glucagon-secreting tumor was seen in the tail of the pancreas in a 69-year-old man. The diagnosis was made by radioimmunoassay of the peripheral blood and the tumor was localized by pancreatic angiography and selective catheterization of the pancreatic veins followed by hormone assay. This technique may be a valuable adjunct in the study of endocrine tumors of the pancreas.


Primary subclavian vein thrombosis and bilateral chylothorax documented by lymphography and venography.

Chylothorax secondary to trauma of the thoracic duct is uncommon. "Stress" thrombosis of the subclavian is a better recognized entity. The occurrence of both in the same patient is documented and their relationship discussed.


Radiographic and pathologic features of spinal involvement in diffuse idiopathic skeletal hyperostosis (DISH).

The vertebral involvement of DISH is described from an evaluation of 215 cadaveric spines and 100 patients with the disease. Radiographic features include linear new bone formation along the anterolateral aspect of the thoracic spine, a bumpy contour, subjacent radiolucency, and irregular and pointed bony excrescences at the superior and inferior vertebral margins in the cervical and lumbar regions. Pathologic features include focal and diffuse calcification and ossification in the anterior longitudinal ligament, paraspinal connective tissue, and annulus fibrosis, degeneration in the peripheral annulus fibrosis fibers, L-T-, and Y-shaped anterolateral extensions of fibrous tissue, hypervascularity, chronic inflammatory cellular infiltration, and periosteal new bone formation on the anterior surface of the vertebral bodies.


Radiologic classification of posterior dislocations of the hip: refinements and pitfalls.

Seventeen traumatic hip dislocations seen during a 15-month period were evaluated. In 10 of the 14 cases of posterior hip dislocation, the final Thompson-Epstein classification differed from the initial radiographic classification. Dislocations of the hip often result in radiographically obscure femoral head and acetabular damage. High quality radiographs with oblique and coned-down views are of substantial aid in evaluating the dislocated hip. After closed reduction of a dislocated hip, further views and tomography are helpful but diagnostic pitfalls exist. A persistently widened hip joint, even with negative plain films and tomography, indicates possible intra-osteochondral debris or incompletely reduced femoral head fragments.


Solitary lytic lesion of the skull.

Thyroid carcinoma metastatic to the calvaria may result in a lytic, well-circumscribed lesion the appearance of which necessitates differential consideration of lytic lesions of the skull. The merits of angiography in the study of such lesions are noted. Even in young persons, the possibility of metastasis presenting as a solitary lytic defect in the skull must be kept in mind.


Computed tomography in the diagnosis of pseudotumor cerebri.

The authors reviewed 17 patients with the clinical diagnosis of benign intracranial hypertension (pseudomotor cerebri). All of these patients underwent CT scans of the head which were interpreted as normal. Comparison of mean ventricular size with that of a group of control subjects showed no significant difference. On the basis of this study and others cited, there would appear to be almost no instances in which invasive neuroradiological procedures would be required to confirm the diagnosis of pseudotumor cerebri.


The normal range and position of the pineal gland on computed tomography.

Precise measurements with the Vanguard Motion Analyzer were made to determine the position of the pineal gland as shown on the Polaroid displays of 145 normal scans. The relatively midline positions of the gland are expressed in terms of percentage shift of the gland in these 145 normal cases is defined by a mean value of 0.8% with a standard deviation of 0.6%. More than 99% of normal CT scans can be expected to show a percentage shift of 2.6% or less.


Computed tomography in a community hospital.

Computed tomography may be effectively utilized in the radiology department of a community hospital. An ideal program features regional services, 7-day, 24-hour coverage, immediate response to emergencies, prompt reporting, and availability of ancillary hospital services. Experience indicates that early scanning may eliminate the need for invasive diagnostic procedures, prevent or shorten hospital stay, and minimize the morbidity and expense of neuroradiological diagnosis.


Myelography in the evaluation of paravertebral mass lesions in infants and children.

The clinical, pathological, and radiological features in 21 pediatric patients with intraspinal extension may be present in the absence of either neurological symptoms or bony abnormalities. It is essential that myelography be performed prior to thoractomy or laparotomy in such cases.


Paraspinal muscle infarction. A painful complication of lumbar artery embolization associated with pathognomonic radiographic and laboratory findings.

Severe, prolonged back pain was observed in 2 patients following lumbar artery embolization with Gelfoam for angiomatous spinal lesions. Dense, persistent staining of the paravertebral muscles with a characteristic striated pattern and elevated levels of creatine phosphokinase suggested muscle infarction and necrosis. Similar angiographic and laboratory findings were reproduced in monkeys following arterial embolization with Gelfoam.


A noninvasive technique for the study of cardiac hemodynamics utilizing C15-O2 inhalation.

A new technique for the study of cardiac hemodynamics is described which utilizes single-breath inhalation of C15O2 (T 1/2 = 124 sec.) and the recording of activity vs. time curves with scintillation counters placed externally over the left ventricle and right lung. The results from 10 normal volunteers and 28 patients with acquired or congenital heart disease have been compared to the findings at cardiac catheterization. The technique is safe, rapid, and nontraumatic, and yielded no false positives or negatives in this series.


Inhalation scintigraphy with radioaerosols in bronchogenic carcinoma.

Radioaerosol inhalation lung scintigraphy is discussed and its interpretation based on the segmental anatomy of the lung is presented. Correlation between bronchography and inhalation scintigraphy in 26 cases of bronchogenic carcinoma showed that partial obstruction of a major bronchus produces a clear "hot spot" with peripheral decrease of aerosol deposition, while partial or complete obstruction of the segmental bronchi causes segmentally decreased deposition distal to the site of obstruction. Even at an early stage, bronchogenic carcinoma may be detected by aerosol inhalation scintigraphy whenever the tumors are large enough to produce visible abnormalities of aerosol deposition.


Brain scintigraphy in recurrent medulloblastoma.

Twenty-three patients with previously treated medulloblastoma had brain scintigrams revealed posterior fossa recurrence in 15 patients and supratentorial metastases in 9; only 1 of the latter was clinically suspected. Two subdural hematomas and one calvarial metastasis were also detected. Comparison with other diagnostic evidence shows agreement in 13 out of 14 cases (93%) for posterior fossa recurrence and 8/10 (80%) for supratentiorial masses. Brain scintigraphy appears to be a sensitive and specific test for the detection of recurrence and metastasis in patients with treated medulloblastoma.


Observation of the use of 99mTc-phosphate imaging in peripheral bone trauma.

The utility of 99mTc-phosphate imaging of fractured bones adjacent to joints soon after injury is examined. Joints usually respond to trauma by a generalized increased regional concentration of the radiopharmaceutical; but with careful attention to technique, a superimposed focal deposition due to the fractured bone can be seen. Fractures which were initially indefinite or which seemed normal at radiography were revealed as early as 7 hours after injury. In our experience, failure to show a focal concentration beyond 3 days excludes a fracture. However, a focal concentration need not necessarily represent a gross fracture; a ligamentous avulsion of a bone chip and/or periosteum could yield the same picture and not be disclosed by radiography. Radionuclide imaging of joint fractures is a useful adjunct to clinical assessment.


Bone within the breast. Report of a case with radiographic and nuclear medicine features.

A mass containing unusual calcific densities suggestive of bone formation was demonstrated within the breast on xeroradiography. The mass showed a very high uptake of 99mTc-polyphosphate on a total-body radionuclide bone scan and was found to have extensive bone and cartilage formation on pathological examination.


The area and volume of the sella turcica in childhood primary hypothyroidism.

Sellar area and volume are compared to chronological age, stature, and osseous maturation (bone age) in a series of control children of short stature and in those with primary hypothyroidism and idoiopathic pituitary deficiencies. Sellar area is increased most significantly in relation to bone age in primary hypothyroidism; volume is less useful than area in the diagnosis of this disease.


New standards for the assessment of sella turcica volume in children.

New standards for the assessment of sella turcica volume were derived from studies in normal children. Use of these standards facilitates the diagnostic evaluation of children with short stature, since many patients with idiopathic hypopituitarism have abnormally small sella turcica volumes. The sellar volume should be estimated early in the evaluation of the short child and, if found to be small, should serve as a stimulus for prompt, thorough evaluation of pituitary function.


New standards of ossification of the newborn.

Physical and neurological examinations of American and Swedish populations confirm that epiphyseal ossification of the newborn in the shoulder, knee, and foot is related to gestational age. The causes of accelerated, retarded, and dysharmonic osseous maturation of the neonate are reviewed.


Osteonecrosis in patients treated with definitive radiotherapy for squamous cell carcinomas of the oral cavity and naso-and oropharynx.

A group of 381 patients with squamous cell carcinoma of the oral cavity and naso-and oropharynx treated with definitive radiotherapy were analyzed with respect to the incidence and precipitating factors of mandibular osteonecrosis. Elective dental extraction prior to therapy increased the incidence, and dental conservation decreased it. Spontaneous osteonecrosis did not occur with doses less than 6,000 rads in 6 weeks, and was uncommon (1.8%) at doses under 7,000 rads in 7 weeks. At doses over 7,000 rads, osteonecrosis developed in 9%. The incidence was greater in patients with tumors near bone (9.4%) than in those with tumors not next to bone (2.1%).


The use of intrauterine and intravaginal radium in the treatment of carcinoma of the bladder in women.

Eight women with advanced stage or high grade carcinoma of the bladder were treated in part with intrauterine and/or intravaginal radium. Local control was achieved in 7 cases. This is an effective form of treatment which should be considered for all women with bladder carcinoma.


The effect of the kVp level on EMI values. Selective imaging of various materials with different kVp settings.

A variety of materials and tissues as well as 3 patients were studied with the EMI scanner using the 100-, 120-, and 140-kVp settings. There was little shift in the EMI value for most tissues over this range, but significant shifts occurred with materials whose effective atomic number was moderately different from that of water. Use of the highest kVp setting may improve visualization of low-contrast images by decreasing the noise caused by statistical fluctuations. This shift in EMI values can be used to determine the approximate amount of material of high atomic number present, such as calcium or iodine.


Evaluation of xeroradiographic image quality.

A theory of edge enhancement has been developed to describe xeroradiographic images of linear step objects. The theory is shown to give an accurate description of the relationship between edge enhancement, subject contrast, radiation exposure, selenium charging potential and developer bias potential. An optimal transmitted x-ray exposure exists which gives the maximum edge enhancement. For low contrast structures, this same optimal exposure was found to yield the most acceptable images as judged subjectively. This finding has led to the successful application of automatic exposure termination in mammographic examinations using xeroradiography.


Wide-field X-ray tube comparisons.

X-ray tubes having similar resolution capabilities along the central ray were compared for their wide-field characteristics. It has been suggested that focal spot size, and therefore resolution capability, along the cathode-anode axis may vary in a manner which is dependent upon the tube target angle. The authors show that differences beyond the effects of target angle occur, the extent of those differences varying from tube to tube. Although 2 different-sized focal spots may be adjusted to have equivalent central beam resolution capabilities, they can exhibit different imaging capabilities at wide-angle (off central axis) position. More than one parameter (equivalent focal spot size) is needed to characterize the behavior of a focal spot.


The metal/tissue interface effect in irradiation of the oral cavity.

Metal dental prostheses or overlays may lead to increased mucosal reactions of adjacent tissue surfaces during intensive irradiation of the oral cavity. The dosimetry of this phenomenon was investigated by irradiating dental phantoms with 4-and 6-MeV photons. Gold and amalgam interfaces may produce local mucosal doses as high as 150-170% depending on the beam geometry, but doses of 111-126% for gold crowns and about 109-118% for amalgam fillings were found for opposed-beam configurations. 2-4 mm of tissue-equivalent absorber is sufficient to re-establish a homogeneous dose distribution and should be employed throughout therapy whenever dental extraction is unwarranted. The radiobiological exaggeration of the interface effect in treatment with opposed beams using one field per day is discussed.


The effects of single and multifraction radiation courses on the mouse spinal cord.

Thoraco-lumbar spinal cord segments of C3H mice were irradiated with 250 kVp x rays and the acute and late effects of several variables were compared: single and multifraction radiation courses; changes in the length of irradiated spinal cord; and multifraction studies in which three-week and three-month splits were compared to a continuous radiation course. A scoring system for assessing the degree of radiation-induced myelopathy was devised, using a scale ranging from 1.0 (loss of rear limb reflex extension) to 4.0 (paraplegia). A significant increase in severity of spinal cord radiation injury was noted when single doses were compared to equal doses given in 10 consecutive fractions. Increasing the irradiated segment from 6 to 12 mm was also associated with more severe and earlier radiation cord injury.


Mammalian cell survival response following irradiation with 4 MeV X rays or accelerated helium ions combined with hyperthermia.

The effects of hyperthermia on Chinese hamster ovary cell radioresponse were studied using either 4 MeV x rays or accelerated helium ions. Both pre-and postirradiation hyperthermic doses act to decrease the slope of the x-irradiation survival curve in a temperature-dependent manner, while the extrapolation number does not change appreciably. Pre-irradiation hyperthermic treatment has only a slightly greater dose-modifying effect than similar postirradiation hyperthermia. For cells irradiated with helium, pre-irradiation at 43 degrees C (1 hr.) changes the radiation survival curve slope and also the extrapolation number, implying that hyperthermia may act more readily to enhance lethal x-ray damage than lethal helium damage, while having a similar effect on the accumulation of sublethal damage for both of these radiations.


Discrimination of normal and overinflated lungs and prediction of total lung capacity based on chest film measurements.

Plethysmography and roentgenography were performed on normal subjects and patients with emphysema. 23 measurements from postero-anterior and lateral roentgenograms were subjected to discriminant and regression analyses to discover (a) which variable(s) best distinguished normal from overinflated lungs and (b) whether these or other variables could be used to predict total lung capacity. A combination of measurements was found to work best in each case.


Computed tomography: contrast media within subdural hematomas. A preliminary report.

Delayed computed tomographic scans may be most helpful in disclosing subdural hematomas which have collected contrast media when the lesion is undisclosed by initial or immediate post-contrast scans.


Oviduct response to glucagon during hysterosalpingography.

Nine patients without evidence of tubal patency at routine hysterosalpingography were given glucagon. Five of the 9 responded with tubal dilation and spill. Three of the 4 who did not respond had a positive history and clinical examination for pelvic inflammatory disease. Data regarding side effects in the 9 patients studied are presented.


Serial radionuclide determinations of the electron fraction with 99mTc-labeled red blood cells.

The reproducibility of area/length ejection fraction determinations was evaluated in 21 subjects using 99mTc-labeled red blood cells (99mTc-RBCs). The ejection fraction was determined within 30 minutes and 3-5 hours after a single injection of 99mTc-RBCs. The mean absolute difference between the initial and subsequent ejection fractions was 7% (maximum, 15%) (r = 0.90). 99mTc-RBCs offer a reproducible method of determining the ejection fraction which is suitable for serial noninvasive evaluations of left ventricular function.


Preparation and evaluation of 111In-labeled leukocytes as an abscess imaging agent in dogs.

Leukocytes labeled with 111In chelated with 8-hydroxyquinoline were evaluated as an abscess imaging agent in dogs. The labeling technique is simple and offers 75-95% efficiency. The half-clearance time of the labeled leukocytes is 6-10 hours, and the target-to-blood activity ratios are higher than those of other compounds now in use. The authors suggest that 111In-labeled leukocytes replace 67Ga citrate as a routine abscess imaging agent.


Low cost intrathyroidal iodine quantification with a fluorescent scanner.

A thyroid fluorescent scanner has proven to be useful for imaging thyroids in cases where isotope scans are contraindicated. Minor modifications of a commercially available scanner make possible total intrathyroidal quantification, which aids in the differentiation between primary and secondary hypothyroidism and in the diagnosis of thyroiditis.


Disparate imaging of the autonomous functioning thyroid nodule with 99mTc-pertechnetate and radioiodine.

Four nodules, visualized with 99mTc pertechnetate at 20-60 min., were not visualized with either 123I or 131I at 2-4 hours. Each nodule was demonstrated to have autonomy of function in excess of surrounding normal tissue when imaged with radioiodine after TSH suppression. Rapid turnover of an iodine moiety would seem to explain this phenomenon better then the trapping-only function previously ascribed to lesions with disparate imaging using pertechnetate and iodine radionuclides.


Is double-contrast examination of the colon the only acceptable radiographic examination?

Recent articles have espoused the sole use of the double-contrast method for radiographic examination of the colon. The author feels that a multitude of complementary techniques should be utilized. Scientific evaluation should determine which study, or studies, are employed.


Computed tomography standardization.

Since the body of literature on computed tomography is growing rapidly, some universally acceptable expression for attenuation values should be adopted. In addition, there is controversy as to the manner of viewing CT scans of the torso: some prefer viewing from below, in the same orientation as conventional radiographs, while the authors prefer viewing from above, consistent with most cross-section anatomy texts and current cranial and body CT displays.


The who, why and how of radiology teaching files.

A variety of teaching files in diagnostic radiology is needed to serve a broad spectrum of purposes and students. A method of acquiring a simplified teaching file to be used for and by medical students, non-radiology house staff, first-year radiology residents and senior staff members is described. The medical student, as a learning experience, acts as the procurer of this file.


On the use of Pantopaque in renal cysts.

Local Pantopaque instillation receives continued support in the urologic and radiologic literature as a method for treating benign renal cysts. If benign renal cysts are a common lesion with an exceedingly small complication rate, what is the rationale for such treatment with a potentially hazardous substance?