Autosomal recessive hydrotic ectodermal dysplasia.

First cousins, a male and a female, with a new type of hidrotic ectodermal dysplasia are described. They were each the result of first cousin marriage from the Egyptian Karaite community. They both had partial adontia, conical peg-shaped teeth, fine hair that did not grow long, normal sweating, eversion of lips, and pronounced facial similarity. The male had cleft lip on the right side while the female had a branchial cyst on the left side of the neck. The parents of both the cases were completely normal. The patients had distinct clinical similarity to the condition described by Witkop (1965) as 'Autosomal dominant dysplasia of nails and hypodontia' but the nails were less affected and the mode of inheritance was completely different.


Occurrence of childhood cancers among sibs and estimation of familial risks.

An analysis which includes the majority of the cases of childhood cancer occurring in Britain over a period of about 20 years suggests that there is a small familial element in the aetiology of these diseases; aggregations within sibships were observed more frequently than would be expected by chance. Possible explanations of these findings are considered. Some, perhaps many, of the cases within such sibships may be due to associations between malignant disease and various genetically determined conditions at a suclinical level or in the heterozygous state. Alternatively, the observed familial aggregations may be attributable to the fact that sibs share a common environment. Childhood cancer in twins is discussed and findings compared with those from the United States. Attention is drawn to a number of interesting combinations of tumours in sibs, particularly brain tumours and bone cancers. The implications of the findings for genetic counselling are discussed; it is emphasized that, though there appears to be an increased risk that sibs of children with malignant disease will also be affected by such diseases, this amounts overall only to a doubling of the general population risk. Whether or not the explanation is a genetic one, the actual magnitude of the risk for such sibs is only about 1 in 300.


Further evidence for a racial difference in frequency of ABO hemolytic disease.

The results of a Coombs test on each infant, age of onset of jaundice, and of maximum recorded serum indirect bilirubin concentration were statisically analyzed on 2,428 consecutive newborn infants who were Rh compatible with their mothers and who weighed 2.5 kg or more. The incidence of ABO isoimmune hemolytic disease was estimated by subtracting the frequency of each of these observations in ABO compatible infants from the corresponding frequency in ABO incompatible infants. This subtraction decreased the contribution of extraneous causes for jaundice and a positive Coombs reaction. As expected, these signs of hemolytic disease were found more often in ABO incompatible infants than in compatible infants. Whether detected by a positive Coombs reaction, jaundice in the first 24 hours, serum bilirubin concentrations over 10 mg/dl, or any combination thereof, the incidence of ABO disease was much higher in black neonates than in white ones. These findings indicate that early discharge of newborn infants from the hospital should not be authorized without specific assessments, especially when the infant is ABO incompatible and black.


Morbidity in breast-fed and artificially fed infants.

One-half of the healthy newborn infants at a rural medical center were initially breast fed; the proportion declined to 4% by one year of age. Breast-feeding was associated with significantly less illnes during the first year, especially if continued beyond 41/2 months of age. Breat-fedding was associated with a higher level of parental education and, by inference, higher socioeconomic status. The health advantage of breast-feeding was still evident after controlling for parental educational status. In better educated families the difference in significant illness between infants who were artifically fed and those who were breast fed for prolonged periods of time was two- to threefold.


Serum bile acid patterns in neonatal hepatitis and extrahepatic biliary atresia.

Serum bile acid patterns were determined in 31 infants ranging in age from 4 days to 24 weeks. Fifteen infants with extrahepatic biliary atresia had a mean concentration of serum bile acids of 90 microng/ml +/- 47 SD;; 16 infants with neonatal hepatitis had a mean concentration of 60 +/- 35.5 SD. The chenodeoxycholate/cholate ratio was greater than one in 13 infants (87%) with atresia and in 10 infants (66%) with neonatal hepatitis. Except for the tendency of a higher total concentration of serum bile acids in infants with atresia, a single serum bile acid value does not differentiate neonatal hepatitis from extrahepatic biliary atresia. The high proportion of chenodeoxycholate in extrahepatic atresia is different from the pattern in other types of cholestatic disease and may reflect an underlying hepatitis.


Glutaric aciduria: biochemical and morphologic considerations.

Biochemical and morphologic studies on a patient with glutaric aciduria are presented. Generalized aminoaciduria, alpha-aminoadipic aciduria, and saccharopinuria were noted just prior to death, as well as glutaconic aciduria greater than beta-hydroxyglutaric aciduria. Mutant liver mitochondria did not oxidize glutaryl-CoA to glutaconyl-CoA, indicating deficiency of glytaryl-CoA dehydrogenase. Autopsy revealed cerebral edema, ischemic neuronal changes, and striatal degeneration in the brain with fatty changes in liver, kidney, and myocardium.


Timed urinary gonadotropin measurements in normal infants, children, and adults, and in patients with disorders of sexual maturation.

Timed urine collections-mostly over a three-hour period-were obtained from 58 newborn, 68 prepubertal children, 27 adolescents, and 51 adults. For comparison, similar samples were collected from 69 patients with presumptive abnormalities of sexual maturation. Follicle-stimulating hormone and luteinizing hormone were extracted by acetone precipitation and measured by radioimmunossay. Adult nem and women excreted approximately 11 times as much FSH and 33 times as much LH as perpubertal children. Elevated and/or diminished excretory values of gonadotropins were associated with appropriate diagnoses of abnormal pubertal advance or delay. Timed urinary FSH and LH measurements can provide a simple, sensitive, and accurate test of gonadotropin function in children.


Theophylline poisoning.

Three cases of theophylline poisoning in young children, two of which occurred after erroneous administration of commonly prescribed pediatric drugs, are presented. The possible association of hyperglycemia and ketoacidosis with severe theophylline toxicity is discussed. Serial serum theophylline levels and half-life determinations for two patients suggest that, although serum half-lives (8.5 hours and 9.0 hours) may be slightly longer than average, drug disappearance followed first order kinetics even at extremely high erum theophylline levels.


Self-disclosure as a function of self-concept and sex.

It was hypothesized that the amount of self-disclosure occurring in a dyadic interaction would be a function of the level of self-concept and the sex of the subjects, with high self-concept subjects and females disclosing more than low self-concept subjects and males. Two hundred and ten subject (105 females and 105 males) were measured for level of self-concept and then paired so that every possible combination of high, medium, and low self-concept subject paired with a partner of high, medium, or low self-concept, and a partner of the same or opposite sex, occurred. The amount of self-disclosure that occurred in the dyadic interaction was measured. It was found that self-concept was significantly related to the amount of self-disclosure. High self-concept subjects were more responsive to the level of self-concept of their partners than were other subjects. There was no relationship between the sex of the subject and the amount of self-disclosure.


Temperament in early childhood.

The structure of temperament proposed by the New York Longitudinal Study (NYLS) of Thomas and collaborators (1963, 1968) was compared to Buss and Plomin's (1975) EASI temperament theory. An objective inventory was developed for the NYLS temperaments. Mothers rated 182 children on both NYLS and EASI temperaments. Only two of the nine NYLS dimensions, attention span-persistence and distractibility, were supported by factor analysis. The four EASI dimensions (emotionality, activity, sociability, and impulsivity) were replicated. A similar sociability factor emerged from both the NYLS and EASI systems, but other temperaments were unique. The NYLS and EASI systems were merged to form the Colorado Childhood Temperament Inventory, a parental rating instrument for children 1-6 years of age.


Development and standardization of instruments measuring four aspects of sex-roles in primary grade children.

Two instruments were developed and standardized on first-, second-, and third-grade boys and girls. The Toy Preference Test (TPT) measures sex-role preference, and/or Stereotypic Sex-Role Concepts of masculinity (SRCm) and femininity (SRCf), depending upon the instructions used for administration. The Rating Scale for Children (RSC) taps sex-role adoption. Subjects were at least third generation U.S. citizens from intact middle-class, Caucasian families. Mean scores for boys and girls were compared and retest reliability coefficients calculated by grade level. The RSC was highly reliable and differentiated sex-role adoption at all grade levels. Similarly, the TPT differentiated the sexes regarding sex-role preference at all grade levels but was reliable for only one sex at each grade level. Boys and girls did not significantly differ in stereotypic sex-role concepts on either the SRCm or SRCf. Reliability coefficients were significant except for the third-grade girls on SRCm, and second-grade boys on SRCf. Patterns of intertest correlations were computed and discussed.


Sustained-release hormonal preparations XV: release of progesterone from cholesterol pellets in vivo.

Progesterone-sterol pellets were made that porvided a zero-order release of progesterone for 80 days. 4-(14)C-Progesterone was used to measure the release in vitro and in vivo. The dissolution rate in vitro (distilled water as the desorbing medium) for progesterone-cholesterol (59:41 w/w) and the progesterone-beta-sitosterol (47:53 w/w) pellets was 72 microng/100 mm2/24 hr. The average in vivo absorption from subcutaneously implanted pellets in rabbits was 2 +/- 0.1 microng/ml of plasma/cm2 of surface area. Of this amount, 20-25% was progesterone; the remainder was progesterone metabolites and conjugates. Zero-order release (plasma levels) was obtained for approximately 80 days or until about 70% of the available progesterone was exhausted. During this time, the level of excreted radioactivity in urine continuously decreased, indicating that monitoring only this parameter would lead to erroneous conclusions. A long-term effect and increased effectiveness were obtained with a 5-20-mg progesterone equivalent dose, using gel prepared from 2% methylcellulose as the suspending medium.


Renal function testing: differentiation between a nephrotoxic agent and diuretic drugs.

Preliminary studies indicate that it may be possible to differentiate the effects of a nephrotoxic substance from those of diuretic agents by the measurement of both urine and plasma osmolarity. The nephrotoxic substance, mercuric chloride, decreases urinary osmolality and increases plasma or serum osmolality. The diuretic agents, at exceedingly high dosages, may show a dose-related decrease in urine osmolality. However, serum osmolality either remains unchanged or is only slightly lowered. This difference in the serum response of animals treated with a nephrotoxin or diuretic agents may allow for the differentiation in toxicological studies.


Instrumentation of an automatic capsule-filling machine.

Techniques similar to those used in instrumenting tablet presses were applied to an automatic capsule-filling machine. The dosing unit was modified to allow the bonding of strain gauges to the compression piston. The guages formed the arms of a Wheatstone bridge circuit. Thus, compression and ejection events were monitored by measuring the bridge unbalance voltage using a suitable amplifier-recording system. The instrumented piston was calibrated in a physical testing machine. Dosing unit rotation required the interposing of a mercury contact swivel between the amplifier and instrumented piston. The instrumentation system required only one minor, permanent modification to the machine, a cut in the dosator tube. Since the same dosator piston sensed both compression and ejection, only one of the two dosing units was instrumented and the other was removed from the machine. A solenoid switching system was devised which only permitted the feeding of empty gelatin shells into the filling cycle for the instrumented piston. Representative fillers were run at constant powder bed and piston heights. Oscilloscope tracings showed two stages in slug formation: (a) "precompression," representing the force sensed during dipping of the dosator into the powder before actual compression, and (b) actual piston compression. Generally, the maximum slug compression force fell to zero rapidly on retraction of the piston, but in some cases a retention force was noted, possibly due to elastric rebound of the slug against the retracted piston. A negative deflection due to binding of the piston also was observed in tracings of one material. Lubricated batches exhibited ejection forces of less than 1 kg.


GLC analysis of acetazolamide in blood, plasma, and saliva following oral administration to normal subjects.

An electron-capture GLC assay for acetazolamide in biological fluids was developed. Extraction efficiency was 69-104%. The minimum detectable amount of acetazolamide was 10 ng/sample. Concentrations of acetazolamide were determined by GLC in blood, plasma, plasma water, and saliva after oral administration of a single 250-mg dose to five volunteers. Erythrocyte levels were calculated from whole blood and plasma data. Concentration of free drug in the plasma was measured in samples of plasma water obtained by microultrafiltration. Peak plasma levels of 10-18 microng/ml were reached 1-3 hr after the dose. At least 1 hr later, erythrocyte levels reached peak concentrations of 13-29 microng/ml. Over 31 hr, plasma levels declined more rapidly than erythrocyte levels. Saliva concentrations averaged 1% of those in plasma and decreased at a rate equal to that of plasma. Saliva levels were proportional to, but not equal to, water concentration. Saliva to plasma ratios were consistent for any given individual and, therefore, offer a means of monitoring drug dosage without resorting to frequent blood sampling.


Pharmacokinetic analysis of drug concentration data obtained during repetitive drug administration.

A digital computer curve-fitting method, designed to estimate pharmacokinetic model constants by utilizing all drug concentration-time data collected during repetitive dosing studies, was applied to data manifesting systematic dose-to-dose variability in one or another of the pharmacokinetic parameters. The method accurately determined dose-to-dose changes in absorption or elimination rate constants or in the apparent volume of distribution, and it would be useful for detecting phenomena such as self-induction and self-inhibition that may occur during multiple-dose administration. The method can also be used to analyze multiple-dose data of drugs exhibiting capacity-limited elimination and to obtain estimates of the Michaelis-Menten parameters.


Synthesis of 14C-meglumine salicylate and its disposition in humans after oral administration.

The synthesis of 14C-meglumine salicylate was accomplished by heating 14C-meglumine with salicylic acid, in equimolar ratios, in 2-propanol. The average radiochemical yield was 97.5%. Ten healthy adult male volunteers were given 1.2 g of the compound orally. Five took 1.2 g of 1-deoxy-1-[14C]-methylamino-D-glucitol salicylate (containing about 47 micronCi), and five others took 1.2 g of 1-deoxy-1-methylamino-D-[U-14 micronCi), and five others took 1.2 g of 1-deoxy-1-methylamino-D-[U-14C]-glucitol salicylate (containing about 45 micronCi). Urine and feces were collected for 5 days, and blood was sampled for 24 hr. The peak urinary excretion of meglumine and/or its metabolites occurred between 4 and 8 hr after administration (about 7.2% of the administered dose). Meglumine was excreted primarily in the feces (72.4% over 5 days) and, to a smaller extent, in urine (21.3% over 5 days). No activity was detected in blood. The excretion rate and percentage excreted were the same for both groups of subjects, suggesting that meglumine was not metabolized by N-demethylation or conversion to carbon dioxide. The highest blood salicylate level, 44.4 +/- 1.9 microng/ml, was observed 1 hr after administration. Urinary levels of salicylic acid and its metabolites were observed to be at a maximum at 8 hr. Total salicylate recovery was 94.7 +/- 1.5% in 48 hr. Salicyluric acid was the major metabolite, accounting for 69.5 +/- 3.6% of the dose. Salicylic acid accounted for 6.8 +/- 1.2%.


Dissolution profiles for multisized prednisolone acetate suspensions.

Particle-size measurements and in vitro dissolution characteristics of commercial and formulated suspensions of prednisolone acetate were determined using a resistance particle counter and a spinning filter apparatus, respectively. Significant differences in dissolution rates were noted for the commercial suspensions. Particle size affected  dissolution but did not account for all observed variations in the dissolution rate. Formulation differences, specifically the presence of hydroxypropyl methylcellulose, in suspensions seemed to be important in dissolution.


Selective GLC determination of epinephrine, isoproterenol, and phenylephrine in pharmaceutical dosage forms.

A simple, specific GLC analytical procedure for the quantitation of epinephrine, isoproterenol, and phenylephrine in commercial tablets, powders, inhalation solutions, ophthalmic and nasal drops, and injectable preparations is presented. Samples are taken to dryness where required, the dried residue is reacted with an appropriate trimethylsilylating reagent, and the derivatives are eluted from a methyl silicone column using temperature programming. Quantitation of the flame-ionization detector signal is achieved relative to the dibenzyl succinate internal standard by an electric integrator. The results obtained by applying the method to the analysis of each of the three drugs in several simulated decomposed mixtures were in good agreement with theoretical values, even at impurity levels of up to 80% by weight. When applied to commercial formulations, the procedure was feasible for tablets, powders, and solutions at drug concentrations of 0.2% or greater. The commonly incorporated buffering and antioxidant excipients did not interfere.


High-performance liquid chromatographic analysis of isoniazid and its dosage forms.

A high-performance liquid chromatographic analysis is described for isoniazid as a drug entity and in its tablet and injectable dosage forms. After incorporation of the drug or dosage form in a solvent mixture and addition of an internal standard, tribenzylamine, an aliquot is chromatographed using a pellicular silica gel medium followed by UV spectrophotometric detection at 254 nm. The response of the chromatographic system was linear over a concentration range corresponding to 20-200% of the labelled amount of isoniazid. Comparison of the results with those obtained by the official USP XIX method indicates similar accuracy and precision. The advantages of the proposed method are its simplicity and rapidity, its potential for automation, and its specificity. The specificity was demonstrated in the presence of potential degradation products of isoniazid, other drugs used with isoniazid in combination dosage forms, and an adduct formed by the reaction of isoniazid with lactose in the tablet.


Comparative pharmacokinetics of coumarin anticoagulants XXI: effect of plasma protein binding on distribution kinetics of warfarin in rats.

The purpose of this investigation was to determine the effect of plasma protein binding on the pharmacokinetic parameters for warfarin that are used conventionally to describe its distribution kinetics on the basis of the time course of plasma warfarin concentrations. Following rapid intravenous injection, warfarin concentrations in the plasma of 14 selected adult male rate declined triexponentially, with the terminal exponential phase starting at about 5 hr. The free fraction, f, of warfarin in the serum of individual animals ranged from 0.303 X 10(-2) to 2.89 X 10(-2). The parameters of the equation Ct = Pe-theta + Ae-alphat + Be-betat for plasma concentration Ct at time t were obtained from the experimental data by nonlinear least-squares computer fitting and varied markedly between animals. Strong and highly statistically significant positive correlations with f were obtained for P, B, and beta, but no significant correlation was found for A, theta, and alpha. Rate constants and apparent volumes for a three-compartment open mammillary model with elimination from the central compartment were calculated. No apparent correlation was found between f and the intercompartment distribution rate constants. However, strong positive correlations between f and the elimination rate constant, the volume of the central compartment, and the volume of distribution, V area, were observed. There also was a strong linear correlation between f ant total clearance. Excellent replication of the experimental data was obtained when the experiment were repeated in some animals after 2 weeks. A detailed analysis of practical pharmacokinetic problems associated with and revealed by such repeated experiments is presented.


High-pressure liquid chromatographic analysis of drugs in biological fluids II: determination of an antiarrhythmic drug, tocainide, as its dansyl derivative using a fluorescence detector.

A sensitive and specific method is described for the determination of a new primary aliphatic amine antiarrhythmic drug, tocainide. Tocainide, together with an internal standard, is selectively extracted from plasma or blood and reacted with dansyl chloride. The highly fluorescent dansyl derivatives are separated using high-pressure liquid chromatography and measured using a fluorescence detector. The method can measure therapeutic and subtherapeutic concentrations of the drug (0.1-5.0 microng/ml of plasma) with a standard deviation of less than 2%.


GLC determination of methenamine in tablets.

A rapid and sensitive GLC method was developed for the quantitative determination of methenamine in tablets. The method was shown to possess several advantages over the official NF assay. After dissolution of the whole tablet in absolute ethanol and addition of an internal standard (pentylenetetrazol), an aliquot was injected into the gas chromatograph for analysis. The sample was chromatographed using a stainless steel column packed with 10% OV-17 on Chromosorb W-HP. Quantitation was achieved by measuring peak heights. The simplicity, directness, extreme rapidity, and accuracy of the method represents an improvement over the official method and the other proposed assays.


Comparison of two spectrofluormetric procedures for quinidine determination in biological fluids.

Different methods for the spectrofluorometric determination of quinidine in plasma and urine were studied. The alkaline washings of plasma and urine extracts remove fluorescent metabolites, as shown by TLC analysis of urine extracts, and do not lead to a significant loss of alkaloids. The spectrofluormetric assays without alkaline washings of the benzene extract averaged 18% higher than the assays with alkaline washings. Since unchanged quinidine and hydroquinidine are responsible for antiarrhythmic activity, the method with alkaline washing is more appropriate for the control of quinidinemia than are other methods. The therapeutic plasma concentration range becomes 0.8-2.5 microng/ml with this methods.


Polarographic study of new antibacterial isoxazolium salts: 2,3-dialkyl-5-arylisoxazolium perchlorates.

The polarographic reduction of new antibacterial 2,3-dialkyl-5-arylisoxazolium salts is described. The electrode process involves an irreversible two-electron transfer and is pH independent within the 6.0-10.0 range. In more acidic media, hydrogen waves are observed; at higher pH values, a chemical degradation of the isoxazolium salt proceeds. Values of the half-wave potential of the salts are dependent on the polar contribution of the 5-aryl substituents in terms of the Hammett equation. The in vitro minimum inhibitory concentrations of these compounds are best correlated with Hansch PI values.


Flavonoid constituents from Eupatorium altissimum L. (Compositae).

An aqueous ethanol extract of Eupatorium altissimum L. (Compositae) showed confirmed activity in the P-388 lymphocytic leukemia assay in mice, and the chloroform solubles showed both cytotoxic activity in the 9KB carcinoma of the nasopharynx cell culture assay and antitumor activity in the P-388 lymphocytic leukemia assay. Two flavones, eupatorin and 5-hydroxy-3',4',6,7-tetramethoxyflavone, were isolated and identified. Both were devoid of cytotoxic and antitumor activity.


Simultaneous GLC determination of acetaminophen, dichloralantipyrine, and isometheptene mucate.

A rapid GLC assay for acetaminophen, dichloralantipyrine, and isometheptene mucate in capsules was developed. These substances are chromatographed directly, using phenyl methyl silicone gum as the stationary phase. The standard calibration curves are linear up to 14 mg/ml, with a lower limit of sensitivity of 2 mg/ml. This method is simple and rapid and does not require derivative formation.


Thermoregulatory responses as a function of core temperature in humans.

1. Six healthy humans were immersed sequentially in baths maintained at a steady temperature of either 28 +/- 1 or 38-8 +/- 1 degree C. 2. Metabolic heat production was calculated by respiratory gas analysis. A ventilated capsule was placed on the forehead and sweat secretion was calculated from psychrometric recordings. Convective heat loss from one hand to water-perfused glove provided a continuous measurement of vasomotor response. 3. Heat production, sweating, and vasomotor heat loss were proportional to core temperature. 4. Sweating and vasomotor response were parallel. Vasoconstriction was complete, before the onset of shivering. 5. The thresholds for heat loss and heat production were superimposed, without a 'dead band' core temperature.


Trans-proximal tubular steady-state concentration differences studied by micro-puncture and tissue content of sodium and chloride at varying intraluminal sodium concentrations in vitro in rat kidney cortex slices: evidence for a multisite sodium transport system.

1. With the aid of micropuncture techniques, proximal tubular transepithelial concentration differences for Na (deltaC Na) and chloride (deltaC Cl) were measured in kidney cortex slices at bathing fluid Na concentrations from 10 to 400 m-mole. kg-1. Tissue content of water, Na and K was also measured in such slices. Under steady-state conditions of zero net flux of NaCl and water, deltaC Na represents the sum of active Na transport, factored by the tubular permeability coefficient added to a component of flux due to electrical forces. 2. The relation between bathing fluid Na concentraton and deltaC Na appeared sigmoid in form suggesting an allosteric mechanism for the transport step. 3. Transtubular potential difference, calculated from transepithelial Cl distribution ratios, did not appear constant at the various bathing fluid Na concentrations. Correcting for the effect of these potential differences on the value of each deltaC Na did not convert the sigmoid transport curve to a hyperbolic one, confirming the suggested allosteric nature of the active Na transport step. 4. Intracellular Na content varied linearly with bathing fluid Na concentrations implying free entry of this cation into the cell. This also suggests that the sigmoid transport curve is related to the properties of the active Na transport pump.


Placental transport of sodium in the guinea-pig.

1. The mechanism of placental transport of Na was studied in guinea-pigs in placentae with intact umbilical blood circulation or in the preparation of the placenta perfused in situ. 2. A constant level of 22Na was maintained in maternal plasma for 60 min, and from the quantity of 22Na recovered from the foetus at the end of this period the influx of Na from mother to foetus was calculated. Ligation of the omphalomesenteric vessels (supplying the everted yolk sac with blood) had no effect on the influx, the corresponding values of influx in the control and treated foetuses being 0-235 +/- 0-020 and 0-247 +/- 0-029 micron-mole/min. g foetal weight (n = 6, the limits are S.E. of mean). The specific activity of Na in amniotic fluid was below that of the maternal or foetal plasma Na by two orders of magnitude. These observations indicate that the extraplacental transport of Na into the foetus is negligibly low. 3. The electrical potential difference (p.d.) and unidirectional fluxes of Na across the placenta perfused in situ were measured by means of 22Na and 24Na administered to the opposite sides of the placental barrier. The fluxes varied with the weight of the foetuses whose placentae were perfused. The flux from the maternal to the foetal side was 0-270 +/- 0-017 micronmole/min.g foetal weight, the flux from the foetal to the maternal side was 0-340 +/- 0-018 micronmole/min.g foetal weight (n = 38). The corresponding p.d. was - 20-7 +/- 1-2 mV (foetal side negative). 4. The active component of Na transport across the placenta was calculated from the unidirectional fluxes and the p.d. The active transport was directed from the foetal to the maternal side, and its rate was 0-211 +/- 0-015 micronmole/min.g foetal weight (n = 38). During perfusion of the placenta with KCN (10(-3) M) the active transport decreased by approximately one third. 5. The flux of Na from the foetal to the maternal side of the perfused placenta was higher than the flux from the maternal to the foetal side. A similar asymmetry of Na fluxes was observed in the non-perfused placenta, the flux from mother to foetus being 0-180 +/- 0-013 micronmole/min.g foetal weight and the flux from foetus to mother 0-235 +/- 0-024 micronmole/min.g foetal weight (n = 12). This indicates that the asymmetry of Na fluxes is caused by the anaesthesia and/or by the trauma of the operation rather than by the perfusion of the placenta. 6. The permeabilities of the perfused placenta to Na and sucrose measured simultaneously from the maternal to the foetal side were 0-0767 +/- 0-0183 and 0-324 +/- 0-0094 cm3/min (n = 7y, respectively. The permeability values bear the same relation to each other as the respective coefficients of free diffusion in water, suggesting that the passive transport of Na across the placenta takes place as simple diffusion through wide aqueous channels. 6...


The effects of hypothalamic temperature variation and intracarotid cooling on behavioural thermoregulation in sheep.

1. Shorn-sheep, placed in cold environments, have been trained to turn on infra-red heaters. The effect, on this thermoregulatory behaviour, of warming and cooling the hypothalamus by means of a thermode has been examined. 2. At ambient temperatures of 5, 15, 25 and 35 degrees C; cooling the anterior hypothalamus by means of a thermode, for periods of 20 min, resulted in a marked increase in the rate of using the heaters. 3. At ambient temperatures of 5 and 15 degrees C, warming the anterior hypothalamus for periods of 20 min caused a considerable reduction in the rate of using the radiant heaters. 4. At an ambient temperature of 10 degrees C, a 2 hr period of hypothalamic cooling resulted in an increase in the rate at which the heaters were used for the first 70 min, but after this the effect was reduced and the reduction coincided with a rise of deep body temperature of about 0-75 degress C. 5. At an ambient temperature of 10 degress C, a 2 hr period of hypothalamic warming resulted in a reduction in the rate of operating the heaters during the first 85 min, but after this period the use of the heaters increased and this increase coincided with a fall of about 0-75 degrees C in deep body temperature. 6. At ambient temperatures of 15, 25 and 35 degrees C, the cephalic region was cooled by intracarotid injections of cold saline for periods of 15 min. This procedure lowered hypothalamic temperature by about 1 degree C and produced increases in the rate at which the heaters were used similar to those seen when the thermode was cooled. To elicit marked increases in the rate at which the heaters were used it was not necessary to lower hypothalamic temperature outside the normal range.


The contribution of alterations in cardiac output to changes in arterial pressure reflexly evoked from the carotid sinus in the rabbit.

1. The reflex cardiovascular effects of changes in pressure within the vascularly isolated carotid sinus were examined in seventeen anaesthetized rabbits. The opposite sinus was denervated and both aortic nerves were divided, 2. Comparison of the mean values at sinus pressures of 40 and 200 mmHg showed a large reduction in systemic arterial pressure from 126 to 58 mmHg and a moderate reduction in heart rate, from 287 to 253 beats min-1. Cardiac output, measured by thermal dilution, showed only a small change, a fall from 160 to 148 ml. min-1 kg-1. 3. By contrast with this reduction in cardiac output of just over 7%, total peripheral resistance, derived by dividing mean arterial pressure by cardiac output, was halved, falling from 0-48 to 0-41 mmHg ml.-1 min kg. 4. Thus in the anaesthetized rabbit changes in cardiac output make only a small contribution to the changes in systemic pressure evoked by alterations in carotid sinus pressure. Changes in total peripheral resistance are principally responsible for the effect on systemic pressure. 5. Though the changes in output of the heart were small, there were considerable changes in the work done by the left ventricle which was approximately halved when carotid sinus pressure was raised from 40 to 200 mmHg.


The effects of histamine on skeletal muscle vasculature in cats.

1. Experiments have been made to determine the vascular effects of histamine and the mechanism of histamine-induced oedema formation in cat skeletal muscle. 2. Histamine caused dose-dependent dilatation of resistance vessels and increased intravascular volume over the dose range 1 X 10(-10)-1 X 10(-8) mol/kg min. The dilatation of resistance vessels resulted in dose-dependent increases in capillary hydrostatic pressure. 3. Histamine increased vascular permeability, as measured by accumulation of [131I]human serum albumin in the tissue, during infusions at 1 X 10(-8) mol/kg min but no albumin accumulation could be detected at lower infusion rates. 4. Oedema formation during histamine infusion of 1 X 10(-10) and 1 X 10(-9) mol/kg min seemed to be due to increases in capillary hydrostatic pressure and independent of increased vascular permeability. During infusions of histamine 1 X 10(-8) mol/kg min oedema was due predominantly to increased vascular permeability and to a lesser extent, the increase in capillary hydrostatic pressure.


Long-lasting increases in the tremor of human hand muscles following brief, strong effort.

1. Long-lasting (up to 4 h) increases in finger tremor were produced by intense brief effort to contract the muscle. 2. Similar increases resulted from intense effort which did not contract the muscle because the motor nerve was blocked. 3. Comparable contractions induced electrically failed to give rise to increased tremor. 4. Power spectral analysis (1-15 HZ) revealed that all frequencies of tremor were approximately equally increased. 5. It is concluded that these long-lasting increases in tremor are of central nervous origin.


Increase in human intestinal permeability following ingestion of hypertonic solutions.

1. A simple oral loading technique involving the ingestion of solutions containing lactulose is described. Timed urinary excretion of lactulose, which is non-metabolizable, is used as an indicator of intestinal permeability, and measured by quantitative paper chromatography. 2. This technique has been used to investigate the intestinal permeability of apparently healthy adults following the ingestion of solutions made hypertonic by the addition of the solutes sucrose, glucose, mannitol, glycerol, urea and sodium chloride. 3. These experiments show that intestinal permeability to lactulose increases as the solute concentration in the ingested solution is increased. Susceptibility to this effect, though consistent for each individual, shows considerable variation between subjects. 4. Factors thought to be pernitent to the enhancement of intestinal permeability by hypertonic solutions, and some possible implications of this, are discussed.


Effects of glucagon on canine intestinal sodium and water fluxes and regional blood flow.

1. Glucagon (0-05 or 0-5 microng/kg. min) was infused into a mesenteric artery of a canine ileal segment from which transport was measured (direct infusion) or into a mesenteric artery of an adjacent non-perfused segment (indirect infusion). Unidirectional Na and H2O fluxes and arterial and mesenteric vein pressures and total and absorptive site blood flows were measured. 2. Direct glucagon infusion increased the absorptive and secretory fluxes of Na and H2O and absorptive site blood flow, and decreased absorptive site resistance and arterial and mesenteric vein pressure. Indirect glucagon infusion had the opposite effects. 3. Neither the direct arterial infusion of histamine (0-1-53 microng/kg. min) nor the I.V. infusion of glucose (0-2 g/min) or insulin (0-1 micron/kg) or glucose plus insulin, mimicked the effects of glucagon. 4. The unidirectional secretory and absorptive fluxes of both Na and H2O were linearly related to the calculated capillary pressure during glucagon infusion. 5. It was concluded that the effects of glucagon on gut transport were due to effects exerted through the cardiovascular system.


Substrate-limited function and metabolism of the isolated perfused rat kidney: effects of lactate and glucose.

1. The objective of this study was to determine the separate contributions of exogenous substrate and of kidney tissue to the support of function and metabolism in the isolated perfused rat kidney. The effects of the addition of L(+) [U-14C]lactate or D[U-14C]glucose either to a specially prepared substrate-free albumin (SFA) or to Fr. V bovine serum albumin (Fr. V-BSA) were compared. The Fr. V-BSA has significant quantities of lactate, citrate and free fatty acids associated with it. 2. Perfusion of the rat kidney with the Krebs-Ringer bicarbonate solution containing SFA, without addition of exogenous substrate, resulted in a lower % Na+ reabsorption (approximately 43%) than when the perfusions contained Fr. V-BSA (approximately 80%). Thus, kidney tissue can support at most 45% of Na+ reabsorption, while the substrates associated with the Fr. V-BSA can support approximately 30% of Na+ reabsorption. When the initial concentration of L(+)lactate in the perfusate containing SFA was progressively raised from 0 to 10 mM, % Na+ reabsorption increased to between 85 and 90%. 3. The apparent Km (0-59 mM) and the Vmax (0-67 micronmole g-1. min-1) for lactate oxidation in the presence of SFA were both significantly lower than when Fr. V-BSA was present (Km = 2-0 mM; Vmax = 1-1 micronmole g-1. min-1). The lower Km is interpreted as being due to the removal of substances from the Fr. V-BSA which competitively inhibit either the uptake or oxidation of lactate; the lower Vmax is considered to be related to the lower rate of Na+ reabsorption when SFA is present. 4. Addition of glucose enhanced gomerular filtration rate in the presence of both types of albumin. The resulting increase in the filtered load of Na+ in the presence of glucose was associated with either no change (Fr. V-BSA) or an increase (SFA) in fractional Na+ reabsorption. Although absolute Na+ reabsorptive rate was greater in the presence of glucose than in the presence of lactate, the oxidation rate of glucose, on a carbon-atom basis, was less than 50% of the oxidation rate of lactate. 5. The metabolism of glucose may regulate the permeability characteristics of the glomerulus and the tubular epithelium: by contrast, the high oxidation rate of lactate suggests it can provide direct support for a major fraction of the Na+ actively absorbed.


Temperature and amplitude dependence of tension transients in glycerinated skeletal and insect fibrillar muscle.

1. Quick stretches and releases were applied to small bundles of glycerinated fibres of rabbit psoas and insect fibrillar flight muscle. The resulting tension changes were recorded at various temperatures and amplitudes of length change. The results from the two preparations had many features in common. At temperatures near 0 degrees C the asymmetry of the initial tension recovery after stretch and release originally reported in living frog fibres by Huxley & Simmons (1971 alpha) was very obvious. 2. The complete tension course could be described as an elastic change occurring simultaneously with the length change followed by recovery consisting of the sum of a number of exponential terms. These terms usually corresponded to the phases discernible without curve fitting, but in some cases a monotonic rise or fall of tension was seen to consist of two components only after curve fitting. 3. After either stretch or release there was a phase of rapid tension recovery towards the value before the length change. The rate constant of this phase increased as the amplitude of stretch or release was increased to about 2 nm/half sarcomere. At higher amplitudes it remained nearly constant 4. At temperatures near 0 degrees C there was a second and much slower continuation of the recovery after stretch. The rate constant of this second phase was much more sensitive to temperature than that of the first phase and it became slower with increasing amplitude of stretch. As the temperature was raised the speed of the second phase approached the speed of the first phase so that at room temperatures the initial tension recovery after stretch and release was nearly symmetrical. 5. Under many conditions these processes were followed by a change in the opposite direction, the 'delayed tension' described by earlier workers. This third phase of tension change had about the same temperature sensitivity as the second phase of the recovery seen after stretch. The tension due to stretch activation was not maintained in rabbit muscle, resulting in a fourth possible phase, a recovery of tension towards the value before the length change. This was absent or of low amplitude in insect flight muscle. 6. We interpret these tension changes on the basis of an extension of the non-linear model described by White & Thorson (1972). The elastic tension change and the initial fast recovery are both supposed to be properties of the attached cross-bridges, whilst the slower recovery is considered to be due to the detachment of cross-bridges which happened to be attached at the instant the length change was applied. The delayed tension reflects the approach to equilibrium of the number of attached bridges, changed by an effect of muscle length on the attachment rate. The fact that the delayed tension is not maintained in rabbit psoas muscle may be due to the effect of length on attachment rate being transitory.


Rectification in Aplysia statocyst receptor cells.

1. Membrane slope resistance of Aplysia statocyst receptor cells was measured by passing constant current pulses, using a bridge circuit. In response to downward tilt all cells which responded exhibited depolarization but this could be accompanied by either decrease, increase or no measurable change in slope resistance, depending on resting membrane potential. 2. By altering membrane potential with d.c. and measuring slope resistance with constant current pulses, these cells are shown to exhibit both anomalous and delayed rectification. Either hyperpolarization or depolarization from one potential can cause the slope resistance to decrease by as much as a factor of 5. 3. The response to standard tilt can be changed from an increase in slope resistance to a decrease, or vice versa, by altering membrane potential. 4. When membrane potential was held constant during downward tilt, the slope resistance always decreased. 5. Slope resistance, the voltage response to standard tilts and the amplitude of membrane potential fluctuations all vary with average membrane potential in a similar manner. 6. These findings are incorporated into a circuit model in which anomalous and delayed rectification are represented by voltage-controlled elements. the response to tilt is always modelled as introducing a parallel conductance pathway with a large positive reversal potential. 7. The model demonstrates that slope resistance can be increased by adding a parallel shunt pathway if the latter brings the membrane out of the anomalous rectification region. 8. The model also demonstrates how delayed rectification can greatly alter the reversal potential inferred from measurements at potentials below actual reversal.


Factors affecting the distribution of chloride ions in rat renal outer medulla.

1. The intracellular Cl- concentration, [Cl-]1, of rat renal outer medullary slices has been studied in iso-osmolal media containing 42, 93, 144, 189 or 225 mM chloride, [Cl-]0. Equilibrium values for [Cl-]1 were attained within 25-50 min from the start of incubation such that [Cl-]1/[Cl-]0 = 0-46. This ratio was independent of [Cl-]0 within the range studied. Intracellular Na+ was unaffected, and only minor variations of cell volume were observed (calculated from slice weight changes and [14C]carboxyl inulin spaces. 2. When [Cl-]0 = 189 mM, [Cl-]1 remained constant at 87 mM for up to 50 min, indicating that these figures may represnet the interstitial [Cl-] and mean intracellular [Cl-] respectively in outer medulla. 3. Omission of bicarbonate from medium containing 189 mM-Cl- caused an increase in [Cl-]1/[Cl-]0 to 0-58, which was not significantly affected by anoxia or by the presence of arsenite (5 X 10(-3) M) or 2,4-dinitrophenol (10(-3) M). Significant further increases were observed in the presence of iodoacetic acid (5 X 10(-3) M) (0-70), acetazolamide (10(-3) M or 5 M 10(-3) M) (0-71) and iodacetic acid plus 2,4-dinitrophenol (0-85). The addition of the diuretic agents ouabain, ethacrynic acid-cysteine and frusemide (all 10(-3) M) to 189 mM-Cl- media containing bicarbonate reduced [Cl-]1/[Cl-]0 to 0-36, 0-37 and 0-42 respectively. 4. The mean 36Cl- space of outer medulla after 50 min incubation in 189 mM Cl- medium was 49-7 +/- 2-1 micronl./100 mg wet wt. The volume of distribution was not significantly affected by ouabain, ethacrynic acid-cysteine or frusemide (10(-3) mM). 5. Net efflux of 36Cl- from slices loaded with isotope into 'cold' 189 mM Cl medium showed three components with rate constants of 69 X 10(-3), 18 X 10(-3) and 9-9 X 10(-5) sec-1 respectively. Efflux was not affected by ouabain, ethacrynic acid-cysteine or frusemide (10(-3) mM). 6. The main conclusions drawn from this study are: (i) the interstitial fluid Cl- concentration of normally hydrated rat outer medulla is approx. 189 mM; (ii) the [Cl-]1/[Cl-]0 ratio 0-46 may represent a chiefly passive distribution maintained by the opposing gradient of a second anion, probably bicarbonate; (iii) the energy required to maintain unequal distribution of Cl- in the absence of external bicarbonate is derived chiefly from glycolysis, with a small aerobic component; (iv) there may be two intracellular chloride pools whose net rates of Cl- exchange differ by a factor of approx. 180.


Sleep and respiration of rats during hypoxia.

1. The effects of hypoxia on slow-wave sleep (SWS) and of SWS on respiratory responses to hypoxia were investigated on rats provided with chronically implanted cortical electrodes. 2. During the daytime (5-7 hr periods) the proportion of time spent in SWS was 45% (S.E. +/- 1.0%) when the rats breathed air. Exposure to 10% O2 (equivalent to 18,000 ft.) reduced this proportion to 27% (S.E. +/- 2.5%). During hypoxia the intensity of e.e.g. activity in SWS (mean, rectified slow-wave voltage) rarely equalled the normal values characteristic of the same rats in fully developed SWS breathing air. The normal pattern of 5-15 min episodes of SWS was changed by hypoxia to a series of brief (2-3 min) incompletely developed episodes. 3. Addition of CO2 to inspired gas failed to prevent the reduction of SWS during hypoxia. CO2 in normal O2 did not alter sleep significantly. The effects of hypoxia on sleep therefore depend upon changes in O2 pressure rather than upon changes in CO2. 4. The effect of SWS on respiration of rats breathing air was to decrease frequency and minute volume by 10-20%. In hypoxia, however, the frequency increased markedly when the animals entered SWS ; minute volume was not significantly changed. It follows that stimulation of breathing by hypoxia is greater during SWS than during wakefulness. 5. The anomalous increase of respiratory frequency when hypoxic rats entered SWS was abolished by addition of CO2 to the hypoxic gas mixture. 6. Steady-state gaseous metabolism (Vo2 Vco2) was decreased 18 +/- 3% during hypoxia and was increased 31 +/- 4% during exposure to 5% CO2. The implications of these changes for interpretation of respiratory responses to O2 and CO2 are discussed.


Sodium efflux from voltage clamped squid giant axons.

1. The efflux of radioactive sodium was measured from squid axons during simultaneous voltage clamp experiments such that it was possible to determine the efflux of sodium associated with a measured voltage clamp current. 2. The extra efflux of sodium associated with voltage clamp pulses increased linearly with the magnitude of the depolarization above 40 mV. A 100 mV pulse of sufficient duration to produce all of the sodium current increased the rate constant of efflux by about 10(-6). 3. Application of 100 nM tetrodotoxin eliminated the sodium current and the extra efflux of radioactive sodium. 4. Cooling the axon increased the extra efflux/voltage clamp pulse slightly with a Q10 of 1/1-1. On the same axons cooling increased the integral of the sodium current with a Q10 of 1/1-4. 5. Replacing external sodium with Tris, dextrose or Mg-mannitol reduced the extra efflux of sodium by about 50%. The inward sodium current was replaced with an outward current as expected. 6. Replacing external sodium with lithium also reduced the extra efflux by about 50% but the currents seen in lithium were slightly larger than those in sodium. 7. The effect of replacing external sodium was not voltage dependent. Cooling reduced the effect so that there was less reduction of efflux on switching to Tris ASW in the cold than in the warm. 8. The extra efflux of sodium into sodium-free ASW is approximately the same as the integral of the sodium current. Adding external sodium produces a deviation from the independence principle such that there is more exchange of sodium than predicted. Such a deviation from prediction was noted by Hodgkin & Huxley (1952c). 9. Using the equations of Hodgkin & Huxley (1952c) modified to include the deviation from independence reported in this paper and its temperature dependence, one can predict the temperature dependence of the sodium efflux associated with action potentials and obtain much better agreement than is possibly without these phenomena. 10. This deviation from independence in the sodium fluxes is the type expected from some kind of mixing and binding of sodium within the membrane phase.


Renin release and autoregulation of blood flow in a new model of non-filtering non-transporting kidney.

1. A recently developed model of a non-filtering, non-transporting dog kidney, obtained by an in situ filling of tubules with low-viscosity oil, was applied for studies of renin release and autoregulation of renal blood flow (RBF). 2. Renal blood flow was partially autoregulated after oil blockade of tubules, as indicated by a mean autoregulation index (Semple-de Wardener (1959) of 0-5. This was comparable to autoregulation of the stop-flow kidney (index 0-6) and contrasted with abolition of autoregulation after hypertonic mannitol loading at stop-flow conditions (index 1-1). 3. The aortic construction at a suprarenal level, which decreased renal perfusion pressure of the oil-blocked kidney 35 +/- (S.E. of mean) 6 mmHg, produced an increase in arterial plasma renin activity of 1-8 +/- 0-1 ng. ml.-1 (P less than 0-02). Renin secretion rate decreased 33 to 70 ng.min-1 in three dogs in which renal perfusion pressure was reduced to 60--66 mmHg, but increased 110 +/- 41 ng.min-1 when pressure reductions were kept within the renal blood flow autoregulation range (n=8, P less than 0-025). 4. These results suggest that signals from the tubular receptor (macula densa) are not necessary for stimulation of renin release or autoregulation of renal blood flow.


Ouabain-sensitive ion fluxes in the smooth muscle of the guinea-pig's taenia coli.

1. Tissues with raised intracellular Na levels, produced by incubation in K-free media, were used throughout. The uptake of 42K by these Na-loaded tissues was followed for 10 min in the presence and absence of 1-37 X 10(-4) M ouabain, this being sufficient to inhibit Na pumping maximally. Subtraction of the uptake seen in the presence from that seen in the absence of ouabain gave estimates of the pumped ouabain-sensitive K uptake. 2. In Na-free (MgCl2) medium this depended on the [K]0 in a sigmoidal fashion with a half maximal [K]0 for activation of some 4mM. The maximal uptake of K was 3 m-mole/kg.min corresponding to a transmembrane flux of some 12-5 p-mole. cm-2.sec-1. 3. In the presence of Na the K activation curve became more obviously sigmoid and higher concentrations of K were needed to achieve a given active K influx. The results were well fitted by assuming that Na and K competed for two identical, non-interacting sites on the external pump face. 4. Addition of K during the efflux of 24Na into a Na-free (MgCl2) medium led to an increased rate of tracer loss. The magnitude of this increase depended on the [K] used in a hyperbolic fashion and it was abolished by addition of ouabain. The [K] causing half-maximal activation of ouabain-sensitive Na efflux was in the order of 1-2 mM. 5. When the [K] in the uptake media was 1-5 mM; Na, Li, Rb and Cs all inhibited ouabain-sensitive K uptake, the order of effectiveness being Rb greater than Cs greater than Na greater than Li. With a E1TKA10 OF 0-15 MM low concentrations of Cs and Rb were shown to stimulate K uptake. Such an effect is predicted by assuming two ion binding sites on the pump's outer face, and that the pump can translocate mixtures of K and either Rb or Cs...


The use of lanthanum to estimate the numbers of extracellular cation-exchanging sites in the guinea-pig's taenia coli, and its effects on transmembrane monovalent ion movements.

1. Tissues were allowed to equilibrate in a Tris-buffered Krebs solution and were then exposed to similar solutions containing up to 5 mM-La. La caused shrinkage and significant losses of tissue K, Na, Mg and Ca. The shrinkage was exactly accountable for by a reduction in the extracellular space (e.c.s.) as measured by [14C]sucrose. No significant change was seen in tissue Cl content. Exposure for 1 hr to 5 mM-La led to a total cation loss of 24-3 +/- 1-6 m-equiv/kg or, correcting for the small change in Cl content, a loss of positive charge of 23-8 +/- 2-2 m-equiv/kg fresh wt. 2. Using the radioisotope 140La it was shown that this loss of cation was balanced by an uptake of La3+. 3. Subtraction of the ions in the measured [14C]sucrose space from the total tissue ion contents led to estimates of the "cellular" ion contents. The effects of 1 hr exposure to 5 mM-La on these were a loss of 12-9 +/- 2-4 m-equiv/kg of cation and a gain of 10-0 +/- 2-6 m-equiv/kg of Cl. 4. Similar changes in ion content were produced by La on "Na-loaded" and "K-loaded" tissues, these being tissues which by exposure to K-free or Na-free (high K) solutions had replaced all their K with Na or vice versa. 5. The uptakes of 24Na and 36Cl by Na-loaded tissues were both describable as the sum of two exponentail processes: a fast component (t 1/2 congruent to 1/2 min), which was presumed to be extracellular and a slower, presumed transmembrane, component. La reduced the rapid component of uptake of 24Na by an amount greater than that predicted by the reduction in the e.c.s., the extra amount lost being some 10--15 m-equiv/kg. La also reduced the amount of rapidly exchanging 36Cl, bwt this reduction was entirely accounted for by the change in the e.c.s. La reduced the rate constant of the slow component of 24Na uptake. 6. La reduced the rapidly exchanging component of 42K uptake by normal tissues by an amount equivalent to about 0-5 m-mole/kg fresh wt. of K in excess of the change in the extracellular space. 7. La had little effect on the effluxes of 36Cl and 42K from normal tissues. However, it reduced the size of the fastest component of exchange of 42K efflux from K-loaded tissues by an amount equal to some 10-15 m-equiv/kg in excess of the reduction in the e.c.s. A similar reduction in the rapidly exchanging component of 24Na efflux from normal tissues was also seen. La slowed the efflux of 24Na from Na-loaded tissues at times when the tracer lost could safely be regarded as intracellular. 8. The taenia coli when exposed to K-free solutions gains Na and loses K. In the presence of La the gain in Na was completely blocked. K was still lost, however, being accompanied by Cl and increased shrinkage. La also prevented the uptake of Na from high Na media by ion-depleted tissues (produced by exposure to sucrose media), while having little effect on the uptake of K from high K media by such tissues. 9 Tedia by such tissues. 9. The cation displaced by La in excess of that lost due to the reduction of the e.c.s...


The influence of sodium on calcium movements and catecholamine release in thin slices of bovine adrenal medulla.

1. 45Ca efflux and uptake, net Ca movements, and catecholamine secretion were studied in thin slices of bovine adrenal medulla. 2. There was a slow component of 45Ca wash-out which is attributed to efflux to intracellular Ca. This efflux was strongly influenced by cations in the external solution, being reduced by 50% when Mg replaced Ca, and the residual efflux being reduced by 80% when choline replaced Na. 3. None of the substitutes tested, choline, K, Li, Tris or sucrose, could replace Na in maintaining 45Ca efflux into Ca-free solution. The Na-dependent Ca efflux showed sigmoidal activation by Na, indicating a requirement for the co-operative action of two or more Na ions in the extrusion of each Ca. 4. In the presence of 3-6 mM-Ca, Na deprivation failed to reduce 45Ca efflux. When K, Li and choline replaced Na the rate constant of 45Ca efflux increased. 5. Ca-dependent 45Ca efflux was studied by adding back Ca to Ca-free solutions. Its activation by Ca was hyperbolic indicating that one external Ca is involved in the extrusion of each Ca, consistent with a Ca:Ca exchange process. The apparent affinity for Ca and the maximal efflux were different in the presence of different monovalent cations. 6. 45Ca uptake was increased when Li or choline replaced Na in a solution containing 3-6 mM-Ca. Net Ca uptake also increased, but to a much smaller extent, supporting the idea of a Ca:Ca exchange process. 7. Mg had little effect in activating or inhibiting 45Ca efflux. Co appeared to act as a weak agonist and weak inhibitor of Ca-dependent 45Ca efflux. Ba strongly activated 45Ca efflux.8. Elevation of [Na]t, with ouabain treatment, did not appreciably affect Na-dependent 45Ca efflux. This may indicate that while this Ca efflux is dependent on external Na, it is not dependent on the Na gradient. Elevation of [Na]i had rather little effect on 45Ca uptake. 9 Exposure of slices to Li or choline solutions evoked a Ca-dependent increase in catecholamine output. This could be attributed to the observed increase in net Ca uptake in these conditions. Sucrose and Tris solutions produced Ca-independent secretory responses with quite different time courses. These results emphasize the importance of the Na substitute used in determining the secretory effect of Na deprivation. 10. Elevation of [Na]i did not change basal catecholamine release, nor did it greatly affect the secretory response to Na deprivation. 11. Only some of the secretory effects of NA deprivation can be attributed to the influence of Na on Ca movements.


Intracerebroventricular taurine in rabbits: effects of normal body temperature, endotoxin fever and hyperthermia produced by PGE1 and amphetamine.

1. Intracerebroventricular (I.C.V.) injections of taurine into rabbits resting at an ambient temperature (Ta) of 10 degrees or 23 degrees C caused hypothermia but at 30 degrees C ambient temperature, rectal temperature was unchanged. 2. An I.C.V. bolus of 0=5 mg taurine immediately followed by a slow infusion of taurine (0-01--0-2 mg/min) into rabbits at 23 degrees C ambient temperature caused sedation and peripheral vasodilation and blocked the febrile response to Salmonella typhosa endotoxin (1 microng/kg i.v.). Sustained fevers, characteristic of fevers caused by central administration of pyrogens, developed after taurine infusions were stopped. Control infusions of taurine at the same rates in the same rabbits when they were afebrile had little effect on rectal temperature. 3. An I.C.V. injection of 0-5 mg taurine reduced the hyperthermia caused by prostaglandin E1 (PGE1; 2 microng) given I.C.V. A dose of 5-0 mg not only blocked PGE1 hyperthermia but also caused marked hypothermia. 4. Bilateral injections of taurine into the preoptic/anterior hypothalamic region, at sites where injections of Salmonella typhosa endotoxin caused long-lasting fevers, had no effect on rectal temperature. Similar injections into the reticular substance of the medulla oblongata, in the region believed to be concerned with a secondary temperature control function, were also without effect on body temperature. 5. Taurine (0-5 and 5-0 mg, I.C.V.) had no consistent effect on hyperthermia induced by amphetamine (2 mg/kg, I.V.) 6. We conclude that the hypothermic effect of taurine is not due to an action on the central neurone pool or pools concerned with the integrative control of thermoregulatory effectors. This amino acid appears to inhibit neuronal activity in efferent pathways which control peripheral vasomotor tone and heat production and to depress the level of arousal. Taurine delays the onset and extends the duration of endotoxin-induced fever, perhaps by two separate action: by inhibiting activity in central thermoregulatory pathways and by promoting accumulation of endogenous pyrogen in the brain.


Very small, very short-latency changes in human breathing induced by step changes of alveolar gas composition.

1. Three healthy young males were maintained for sessions of about 1 hr in a state of mild asphyxia (PA,O2 approximately 55, PA,CO2 approximately 45 torr), i.e. with moderately strong drives from both arterial and intracranial chemoreceptors. Tidal volume (VT), breath duration (TT) and duration of inspiration (TI) were recorded, and ventilation (VE) and duration of expiration (TE) were derived breath by breath. 2. The arterial chemoreceptor component of the drive was briefly and abruptly reduced, perhaps silenced, by three separate procedures: the inspiratory pathway was connected for two breaths to a second gas supply line containing, B, hypoxia with Pi,CO2 zero (removal of hypercapnia with maintained hypoxia); C, pure oxygen (removal of asphyxia); and D, oxygen with 40 torr added PCO2 (removal of hypoxia with maintained hypercapnia). In controls, A, the second inspiratory line contained the maintenance mixture so that the switch involved no change of inspiratory gas composition. Each type of test was repeated twenty-four times on each subject. 3. Responses attributable to silencing of arterial chemoreceptors (i.e. with 1 1/2--3 breath latencies about equal to the lung-to-ear circulation time) are reported elsewhere. 4. Very small responses, occurring only half a respiratory cycle after first inhalation of the test mixture, were detected by pooling all responses of each kind from all subjects. When hypoxia was withdrawn, with (C) or without (D) simultaneous withdrawal of hypercapnia, VT and VE were reduced by 3 and 2% respectively, probably because gas mixtures containing high oxygen concentrations are appreciably more viscous than hypoxic mixtures and so require more effort to breathe in and out. When hypercapnia was withdrawn with (C) or without (B) simultaneous withdrawal of hypoxia, TE was significantly lengthened (mean, + 65 +/- 18 msec), 5. The change of TE was discussed in relation to known effects of CO2 on airway receptors in the dog.


Body fluid changes which influence drinking in the water deprived rat.

1. After overnight deprivation of water both the cellular and extracellular fluid volumes are significantly reduced in the rat. 2. In the rat with functional kidneys oral, intragastric or intravenous preloads of 10 ml. water reduce the total water intake after 1 hr by 64-69%. These preloads restore plasma osmolality to pre-deprivation levels but have little effect on plasma volume. 3. In the same rats if the plasma volume is restored with an oral, intragastric or intravenous preload of 10 ml. of an isotonic balanced salt solution which has little effect on osmolality, drinking is significantly reduced by 20-26%. The reduction of drinking correlated with the volume of the preload of balanced salt. 4. Plasma analysis shown that 1 hr after an oral preload of 10 ml. isotonic balanced salt solution, the extracellular fluid volume of the deprived rats is restored to pre-deprivation levels but osmolality is unchanged. Three hr after the balanced salt preload, extracellular fluid volume is still at pre-deprivation levels and there has been a slight decrease in osmolality due to excretion of salt. 5. In rats which had been nephrectomized or had the ureters ligated so there could be no renal modification of the preloads, the effects of the preloads of water and balanced salt are the same as in rats with intact kidneys. 6. The results indicate that after water deprivation in the rat, changes in both the cellular and extracellular fluid compartment are stimuli to drinking.


Eye- and head movements in freely moving rabbits.

1. Eye- and head movements were recorded in unrestrained, spontaneously behaving rabbits with a new technique, based upon phase detection of signals induced in implanted coils by a rotating magnetic field. 2. Movements of the eye in space were exclusively saccadic. In the intersaccadic intervals the eyes were stabilized in space, even during vigorous head movements. Most of this stability was maintained in darkness, except for the occurrence of slow drift. 3. Many saccades were initiated while the head was stationary. They were accompanied by a similar, but slower head rotation with approximately the same amplitude. The displacement of the eye in space was a pure step without appreciable under- or over-shoot. The deviation of the eye in the head was mostly transient. 4. Other saccades were started while the head was moving and were possibly fast phases of a vestibulo-ocular reflex. The time course of the eye movement in space was identical for all saccades, whether the head was moving prior to the saccade or not. Eye movements without any head movement were not observed. 5. Saccades were mostly large (average 20-6 +/- 12-4 degrees S.D.) and never smaller than 1 degree. The relations of maximal velocity and duration to amplitude were similar to those reported for man. 6. Visual pursuit of moving objects, when elicited, was only saccadic and never smooth. 7. It is concluded that the co-ordination and dynamics of the rabbit's head- and eye movements are similar to those of primates. In the absence of foveal specilization, the eye movements are restricted to a rather global redirection of the visual field, possibly in particular of the binocular area.


[Arteriography in a case of single coronary artery with myocardial ischaemia (author's transl)].

Coronary arteriography is the only examination by which the diagnosis of single coronary artery may be made in vivo by demonstrating the presence of an entire coronary system arising from a common trunk. The discovery may be made under two distinct sets of circumstances: 1 degree Coronary ischaemia in a young subject. Arteriography confirms the diagnosis and the customary 2 degrees Coronary ischaemia in an older individual. Arteriography shows atherosclerotic lesions in a single coronary artery. The severity of the condition is related to the proximal character of the stenoses. The most logical therapeutic approach is aorto-coronary bypass if the quality of the distal network as seen at arteriography makes it possible.


[Value of the technique of intravenous infusion of contrast media for the diagnosis of fluid processes (author's transl)].

The study covered 50 patients suffering from hepatic effusions; a solution used in contrast intravenous psychography was administered to them by the intravenous route, at similar doses to those used in intravenous psychography with infusions. This process which we have called Intravenous Viscerogramme, because of the similarity of the images obtained with those of the viscerographic phase of arteriography, has enabled the diagnosis of 35 hydatidiform cysts, one case of cholangiolar hamartoma and an abscess. Owing to the ease with which it can be carried out, we think that it can be used in the diagnosis of tumoral lesions of the liver. When the result is positive, radiological signs are obtained which enable identification of the lesion, thus avoiding resorting to more complex investigations such as angiography.


[Precision bone densitometry using films without screens (author's transl)].

The new method of indirect bone densitometry proposed evaluates a coefficient of reduction related to the minerals of bone tissue (M.C.R.) by measurement of the blackness of a film without creen exposed to a well-defined monochromatic ray. The M.C.R. is closely related (R=0.98) to the mineral content measured experimentally in bone fragments. It represents a precise evaluation of the "quality" of bone tissue. A.M.C.R. less than normal is seen in hyperosteoidosis syndromes or in the case of increased intraosseous resorption. This relatively simple and cheap method is particularly useful in the detection and observation of osteomalacia, and in bone disorders associated with haemodialysis and hyperparathyroidism.


[Double contrast radiological study of the small intestine with duodeno-jejunal intubation. The technique used at the Nice University Hospital Centr with a report of first results (author's transl)].

The authors have carried out 80 radiological studies by duodeno-jejunal intubation using a tube which they themselves perfected. The technique is simple and easily reveals organic lesions. Barium studies of the small intestine via duodeno-jejunal intubation further makes it possible to assess its tone and peristalsis. The authors feel this technique to be the most suitable for this technique purpose.


[Radiological study of the cervical spinal column in some neurological degenerative diseases (author's transl)].

This study presents the findings from a neuroradiological investigation of the cervical spinal canal in a number of diseases of the nervous system. It concerns the measurement of the sagittal and transversal diameters of the spinal canal at levels C3 through C6. The material for this investigation was made up of two main groups: A) 400 controls and B) 110 patients. The second group consisted of the following: 1) 20 patients suffering from Friedreich's Ataxia, 2) 14 patients with Steinert's disease, 3) 44 patients with lateral amyotrophic sclerosis, 4) 14 patients suffering from Charcot-Marie-Tooth's disease, and 5) 18 patients with muscular dystrophy. The results are as follow: 1) In patients with Friedreich's Ataxia both the sagittal and transversal diameters are smaller than those of the controls. 2) On the contrary, in Charcot-Marie-Tooth's disease the sagittal diameter is larger than the controls. 3) The transversal diameter in patients with muscular dystrophy is smaller than the controls and 4) the sagittal diameter of the vertebral canal decreases from the top (C3) downwards (C6) while the transversal diameter increases.


[The use of arteriography in the pharmacological study of a vasodilator substance].

The administration of a vasodilator substance is followed by the development of a higher contrast gradient in a given film in comparison with a reference X-ray carried out in the same subject under comparable technical conditions. Comparative densitometric measurement of the contrast gradient in the two successive arteriographic series, one with and one without the injection, arterial or venous, of a vasodilator substance (Couramine-Rutine) represents a valuable method for the study in man of the action of the substance in a visceral territory. The present study was limited to the kedney (79 cases), ans the territory of the superior mesenteric (46 cases). The absence of any densitometric difference between the two renal series at too low doses of vasodilator substance leads to the supposition of the possibility of a threshold dose of pharmacological activity.


[An unusual dissecting cyst of the knee in a patient with rheumatoid arthritis].

An unusual synovial cyst of the knee in rheumatoid arthritis is reported. The communication with the knee joint anteriorly under the tibial insertion of the internal collateral ligament is in contrast with all the cases reported to date in the literature. The advantages of the air arthrogram (coupled with the arteriography) over the opaque contrast medium arthrography are shown to be superior for such special case.


[Double-contrast radiography of the small intestine].

On the basis of 170 double-contrast radiographic examinations of the small intestine, a description is given, in the first part of this paper, of the technique employed. Emphasis is laid, on the one hand, on duodenal intubation, which is easily effected with a Dotter-Bilbao tube and, on the other, on a study obtained by filling with a continuous barium column, the double-contrast being merely an adjunct. In the second part of the paper the results are analysed from a photographic and diagnostic standpoint: Photographically, duodenal intubation affords a clearer visualization of the jejunum but the chief merit of double-contrast radiography lies in the visualization of the ileum and the study it makes possible of the last ileal fold. With regard to diagnosis, from personal series, 20 % of organic lesions have been observed, although it must be admitted that this figure is certainly boosted by the selectivity of a specialized gastroenterologic unit. The interest of this technique rests also on the fact that the examination is very well tolerated by the patient and does not last more than two hours on an average.


[Present possibilities of surgery in the treatment of metastases in the limbs].

Present-day techniques used in the surgical treatment of bony metastases of the limbs are described in relation to a series of 116 cases. Emphasis is laid on the possibilities of osteosynthesis or preventive arthroplasty.


Polycystic ovarian disease: clinical considerations.

Although the pathogenesis of the PCO syndrome remains obscure, several endocrine aberrations are clinically measurable in this syndrome. It has been shown that this syndrome is associated with inappropriate gonadotropin secretion and elevated serum LH, A and T levels. Various levels of E2 and E1 have been noted. The evaluation of these individuals should include studies to determine the state of androgen production in them. Treatment should be based upon an understanding of the pathophysiology, a thorough evaluation of androgen production and the patient's expectations based upon age, marital status and desire for pregnancy. The physician's expectations should be related to prevention of endometrial hyperplasia, the restoring of ovulation and amelioration of many of the androgenic side effects seen.


Quantitative structure--activity relationships. 7. The bilinear model, a new model for nonlinear dependence of biological activity on hydrophobic character.

The bilinear model, log 1/C =a log P-b log (betaP+1) +C, a new model for nonlinear dependence of biological activity on hydrophobic character, is applied to 57 data sets of biological activity values in homologous series. From a comparison of the statistical parameters and the residuals obtained with the bilinear model and the parabolic model, the superiority of the bilinear model for a precise quantitative description of both linear and nonlinear parts of sturcture-activity relationships can be derived; the bilinear model explains the particular effect that in homologous series the relationship between biological activity and hydrophobic character is strictly linear for the lower members, while for higher members this relationship is nonlinear.


Study of trans-cyclopropylbis (diketopiperazine) and chelating agents related to ICRF 159. Cytotoxicity, mutagenicity, and effects on scheduled and unscheduled DNA synthesis.

The cytotoxicity, mutagenicity, and DNA damaging potential of trans-cyclopropylbis (diketopiperazine) (3) and chelating agents related to ICRF 159 (1) were examined as a function of concentration and duration of exposure in the Chinese hamster cell line V79A. At a concentration of 10(-3) M, 1 and the trans-cyclopropanediamine tetraacid 8 and ester 7 proved to be cytotoxic and mutagenic. The trans-cyclopropyl analogue 3 of ICRF 159 and acyclic tetraacid 6 were less cytotoxic at all concentrations; analogue 3 exhibited no mutagenic activity at any of the concentrations tested. Compounds 1, 7, and 8, at lethal concentrations, exhibited significantly different mutation frequencies with 7 being sixfold more mutagenic than 8 at the same molar concentration. At 10(-3) M compounds 8 was several times more effective blocking DNA replication than other analogues but did not induce unscheduled DNA synthesis as did 1,3, and 6. With the exception of 8, there was an excellent correlation between mutagenesis and the induction of unscheduled DNA synthesis.


3-Fluoro-1-hydroxypropan-2-one (fluorohydroxyacetone) and some esters. Syntheses and effects in BDF mice.

1-(Benzoyloxy), 1-(4-nitrobenzoyloxy), and 1-(3,5-dinitrobenzoyloxy) derivatives of 3-fluoro-, 3-chloro-, and 3-bromopropan-2-one were prepared by oxidation of the 1-benzoyloxy-3-halopropan-2-ols in turn prepared from the appropriate benzoyl chloride and 3-halo-1,2-propanediols, 1-Benzoyloxy-3-fluoropropan-2-one was allowed to react with acidic trimethyl orthoformate to yeild 1-benzoyloxy-2,2-dimethoxy-3-fluoropropane which upon basic hydrolysis afforded 2, 2-dimethoxy-3-fluoropropan-1-ol (fluorohydroxyacetone dimethyl ketal). This was deketalized with aqueous HCL to afford 3-fluoro-1-hydroxypropan-2-one (fluorohydroxyacetone), the title compound. By reacting 1-chloro-3-fluoropropan-2-one and 1, 3-dichloropropan-2-one with potassium acetate, 1-acetoxy-3-fluoropropan-2-one and 1-acetoxy-3-chloropropan-2-one (fluoro- and chlorohydroxyacetone acetate, respectively) were obtained. Similarly, sodium benzoate and 1-chloropropan-2-one produced 1-benzoyloxypropan-2-one. Stucture-activity relationships are discussed which relate chemical structure, alkylating ability, toxicity, and antitumor effects. Comparative toxicities in mice showed decreasing toxicity, on a molar basis, in the 1-benzoyloxy-3-halopropan-2-one series of bromo greater than fluoro greater than chloro. Ketones were much more toxic than the corresponding alcohols. In general the phosphate and benzoyloxy derivatives are more toxic than acetoxy compounds, with nitro-substituted benzoyloxy derivatives being much less toxic.


Adrenergic agents. 5. Conformational analysis of 1-alkylamino-3-aryloxy-2-propanols by proton magnetic resonance studies. Implications relating to the steric requirements of adrenoreceptors.

Two distinct chemical classes, namely, phenylethanolamines resembling the natural biogenic catecholamines and 1-alkylamino-3-aryloxy-2-propanols (aryloxpropanolamines), exert a distinct action as agonists and/or antagonists of adrenergic receptors. To explore the possibility that these two different kinds of chemicals might share a common ground-state conformation as an essential structural feature that satisfies the specific steric requiremetns for the active site of the receptor, a conformational analysis of some aryloxypropanolamines and related compounds was performed. On the basis of this NMR conformational analysis it is suggested that salts of 1-alkylamino-3-aryl-oxy-2-propanols in a nonpolar solvent may exist in a stable "rigid" conformation involving two intramolecular hydrogen bonds to form a 6-5 bicyclic chelated structure. Comparison of steremodels of this "rigid" bicyclic conformer with the conformationally preferred trans (phenyl to amino) rotamer of adrenergic phenylethanolamines, such as isoproterenol, indicates that all positions of the phenyl ring, the phenyl to oxygen or phenyl to carbon bonds, and the ammonium groups of both chemical classes may be superimposed nearly exactly. A major difference between the two species is the relative steric orientation of the alcoholic hydroxyl groups which are about 2 A removed when models of the two classes of adrenergic agents are superimposed. That a specific steric orientation of this alcoholic functionality may not be an absolute requirement for adrenergic activity is supported by the recent observation of significant activity in the homologue of N-tert-butylnorepinephrine in which a methylene group is inserted between the benzylic carbon and the hydroxyl group. Possibly the different steric location of the alcoholic hydroxyl group may be involved in the altered beta1- and beta2-adrenoreceptor selectivity of phenylethanolamines and phenoxypropanolamines.


5,6,7,8-Tetrahydroguinolines. 4. Antiulcer and antisecretory activity of 5,6,7,8-tetrahydroquinolinenitriles and -thioamides.

A number of 5,6,7,8-tetrahydroquinoling-8-nitriles and -8-thioamides and related compounds have been found to be potent inhibitors of basal gastric secretion in the pylorus-ligated rat and to afford protection against gastric erosions induced in rats by cold-restraint stress. Molecular manipulation has proved useful in determining factors necessary for such activity and structure-activity relationships are discussed. It has been shown that the most necessary requirements for activity are a pyridine nitrogen with its available lone pair and a primary or secondary thioamide. Also desirable is a six-membered carbocyclic ring with relative freedom from steric hinderance around the 8 position.


Piezoelectric transducers for oral force monitoring.

A wide variety of instruments have been developed for oral force monitoring. Most of the instruments, however, have employed bite elements which were too thick for measurement of biting forces when the teeth are nearly in contact and probably stretched the stomatognathic muscular system beyond its maximum power of contraction. This paper reports on the use of piezoelectric transducers (quartz crystals, 1.5 mm thick) to monitor quantitatively biting forces in humans.


Risk of bladder tumors among benzidine workers and their serum properdin levels.

Serum properdin levels were determined for 21 benzidine operators at 6-month intervals for 2 years after termination of exposure to this carcinogen. Of this group, 7 developed bladder cancers within a 4-month period prior to the initial assay, and all 7 showed properdin levels below the median for the group as a whole. Two of the 3 workers who had had a brief exposure previously to beta-naphthylamine developed benign bladder tumors but had no malignant neoplasms up to 13 years later. The properdin assays of these 3 men remained consistently at or above the median values. No man developed a bladder tumor who was exposed less than 6 years to benzidine, even though 2 of these men showed low properdin levels. Of the 4 whose properdin levels were initially above the median but dropped below in subsequent assays, 3 developed bladder cancers 0.5, 4, and 9 years later. Only 1 man whose properdin level remained high in 1958-59 developed a bladder cancer 7 years later, and his immunologic picture may have been complicated by recovery from a larynx tumor in 1954. Recurrence of bladder tumors among the original 9 cases has occurred only among the 5 whose properdin levels remained below the median. The 1 whose ranking fell most dramatically (from 13 to 19) has had 13 recurrences in 13 years.


Growth kinetics of plasma cell myeloma.

The plasma cell labeling index(ex) (LI) of 128 patients with multiple myeloma at various stages of disease was compared as a function of tumor mass load and length of treatment. No significant differences in LI were noted for patients with various degrees of tumor reduction. Patients observed during the first 3 months of treatment had significantly higher LI than did untreated patients and those studied after longer intervals. In vivo cell-cycle analysis of myeloma cells by the halving time of the grain-count method failed to establish the length of the cell cycle but defined the length of S+G2 phases as being longer than 60 hours. Similar studies conducted in vitro defined a shorter combined length of S+G2 phase. In 2 patients in whom continuous infusion with [3H] thymidine was performed, the generation time was established as 8 days. Both patients had similar initial LI (5.7 and 6.6) but different growth fractions (19 and 47%). The measured tumor mass doubling time was much longer than the calculated one, suggesting the presence of considerable intrinsic cell loss (83 and 47%). These observations were summarized by a hypothetical two-compartment model for the growth kinetics of multiple myeloma.


A preliminary Pharmacokinetic study of dianhydrogalactitol (NSC-132313) disposition in the dog.

The pharmacokinetics of dianhydrogalactitol (DAG), NSC-132313, were studied in the beagle dog at doses of 3 mg - kg-1 and 6 mg - kg-1. DAG concentrations in plasma were determined by a gas chromatographic method capable of specifically detecting the parent drug and differentiating between it and products of its degradation or metabolism. Plasma disappearance time curves were generated and shown to follow simple two-compartment model behavior after iv administration of DAG. Distribution and elimination of DAG appeared to be dose-independent in the limited dose range studied. After iv administration, the drug was rapidly distributed throughout extracellular fluids (volume of the central compartment = 462 ml - kg-1) and subsequently was rapidly cleared (total body clearance = 23.4 ml - min-1 - kg-1) and eliminated (t1/2, b = 26.2 min) from the animal. Experiments (in vitro) with the use of radiolabeled DAG indicated that the drug binds reversibly and irreversibly to red blood cells.


An organ culture method for adult colon from germfree and conventional mice: effects of donor age and carcinogen treatment on epithelial mitotic activity.

An organ culture system by which adult mouse colon epithelium could be maintained in a modified form for several weeks was described. The effects of donor age and carcinogen pretreatment were studied as a preliminary to proposed experiments on the effect of carcinogen treatment in vitro on colon epithelium from mice of different ages. Mitotic activity was compared in explants of colon from germfree C57BL mice 5 weeks, 5 months, and 9 months old; no differences were detected. The effect of old age on mitotic activity was not studied, since colon epithelium from old (30 mo) conventional mice could not be maintained in culture. Colon explants from conventional mice that had been pretreated for 32 weeks with weekly doses of a carcinogen, 1,2-dimethylhydrazine, appeared to have a higher potential for mitotic activity in vitro than did those from age-matched, untreated controls, but the difference was only significant at the 10% level. The epithelial cells were normal in ultrastructure, and the method may be valuable for studies of the direct effects of substances on adult colon epithelium.


Ultrastructural comparison of differentiation of stem cells of murine adenocarcinomas of colon and breast with their normal counterparts.

Two rats with chemically induced transplantable adenocarcinomas of the colon were given pulses of [3H]thymidine, and autoradiography with electron microscopes was used to compare the degrees of differentiation of the stem cells of the tumor and colon. The best differentiated portions of the tumor had acini composed of vacuolated, mucous, and argentaffin cells in various stages of differentiation. Vacuolated and mucous cells incorporated [3H]thymidine and corresponded in degree of differentiation to that of their labeled normal counterparts in the normal colon. An exceedingly undifferentiated labeled cell, hitherto undescribed, was identified in the tumor and crypts of the colon; this may be an undifferentiated colon stem cell that differentiates into vacuolated and mucous stem cells and/or into argentaffin cells. Normal stem cells of the breast and malignant stem cells of spontaneous adenocarcinomas of the breast of C3H mice had comparable degrees of differentiation. Since normal stem cells in these tissues were as undifferentiated as the least differentiated stem cells of the tumors, there is now no need to postulate dedifferentiation as a mechanism to explain the undifferentiated appearance of tumors.


Iodoacetate-induced inhibition and enhancement of spontaneous leukemia in AKR mice.

Either inhibition or enhancement of the spontaneous lymphoma exhibited by AKR mice was observed after treatment with different dosages of the sulfhydryl inhibitor, sodium iodoacetate. Treatment of the mice at 3 or 6 months of age with five ip injections of 0.10 mg of iodoacetate at 5-day intervals significnatly extended the survival of the animals. A single administration of this dosage elevated the responses of splenic lymphocytes to the T-cell mitogens phytohemagglutinin (PHA) and concanavalin A (Con A), and resulted in higher PHA and Con A response ratios than were noted for age-matched controls. Conversely, groups of 3- or 6-month-old AKR mice, subjected to the same regimen but with 0.01-mg dosages, exhibited an apparent accelerated development of the leukemia and survived for significantly shorter periods. In general, splenic lymphocytes harvested from mice given a single 0.01-mg treatment of iodoacetate were not as reactive as were control cell cultures when exposed to the T-cell mitogens.


Morphologic character of transforming renal cell cultures derived from Wistar rats given dimethylnitrosamine.

The morphologic character of kidney cells during serial subculture following isolation from Wistar rats treated several hours to 1 week previously with a carcinogenic dose of dimethylnitrosamine (DMN; 60 mg/kg body weight following protein deprivation) was compared with the appearance of cultures derived from normal control rats. Apart from early signs of cell toxicity, cultures from DMN-treated rats appeared similar to those from untreated rats for the first four passages. Control cells underwent senescence usually by subculture 4, whereas the test cultures survived to express morphologic transformation (usually at subculture 5) as dense macroscopic colonies of piled up cells. In 18 of the 20 test cultures, the cell populations that persisted in continuous culture following expression of morphologic transformation were exclusively mesenchymal, closely resembling DMN-induced renal mesenchymal tumor cells in continuous culture. In the remaining 2 test cultures from DMN-treated rats, a persisting population of abnormal epithelium was present in addition to morphologically transformed mesenchymal cells. The occurrence of populations of altered mesenchymal and epithelial cells characterized by prolonged survival in vitro following isolation from rats shortly after treatment with a carcinogenic dose of DMN was believed to be related to the long-term induction in the rat kidney of a high incidence of mesenchymal tumors and a lower incidence of cortical epithelial tumors by the same dose schedule.


Studies with cyclophosphamide labeled with phosphorus-32: nucleic acid alkylation and its effect on DNA synthesis in rat tumor and normal tissues.

The gross distribution of levels of [32P]cyclophosphamide ([32P]CY) in August female rats was similar in tumor, intestinal mucosa, spleen, bone marrow, and striated muscle tissue, with slightly higher levels in liver and kidney tissue. A triphasic association with nucleic acids was found and actual alkylation of DNA and RNA reached a maximum of 48 hours post treatment. There was no evidence of 32P-label reutilization that could have accounted for prolonged alkylation. We found that 100 mg CY/kg suppressed the incorporation of [3H]thymidine, [3H]deoxyuridine, and [14C]sodium formate into the DNA of the BICR-A15 carcinoma for at least 10 days. This correlated well with the observed regression of tumor volume. Bone marrow and intestinal mucosa, two tissues which limit chemotherapuetic treatment of the tumor, were less affected by 100 mg CY/kg. Bone marrow had regained normal levels of DNA precursor incorporation by 5 days, and intestinal mucosa had regained normal levels by 3 days. Results indicated that this differential in recovery time may assist in the successful scheduling of vital tissue-sparing drug regimens.


A potent pancreatic carcinogen in Syrian hamsters: N-nitrosobis(2-oxopropyl)amine.

N-Nitrosobis(2-oxopropyl)amine (BOP), a further postulated beta-metabolite of di-n-propylnitrosamine, induced a high incidence of pancreatic duct adenomas and adenocarcinomas as early as 13 weeks in Syrian hamsters receiving weekly sc injections for life and a few pancreatic adenomas, after 28 weeks, in those given a single sc dose. Compared to related compounds, N-nitrosobis(2-hydroxypropyl)amine and N-nitrosobis(2-acetoxy-propyl)amine which are also pancreatic carcinogens, BOP induced only a few neoplasms of the lung, liver, and kidney and none in the nasal cavity, larynx, and trachea. The results therefore indicate progress in developing a more specific model for pancreatic carcinogenesis studies.


Immunobiology of heterotransplanted human tumors in nude mice.

The immunobiology of heterotransplanted human tumors was investigated following transplantation into nude mice of human bronchogenic, colon, rectal, ovarian, gastric, endometrial, vaginal, bladder, renal, esophageal, embryonic cell, pancreatic, and breast carcinoma, as well as fibrosarcoma, rhabdomyosarcoma, malignant melanoma, astrocytoma, Wilm's tumor, endometrial hyperplasia, and hydatidiform mole. Several of these tumors were passaged up to 15 generations. During these passages no changes in latency period for tumor development or in histology were noted. There were significant differences between several tumors in the minimum number of cells required for successful transplantation; such differences were independent of the basic biologic aggressiveness of the individual tumors. Nude mice that received transplants of fibrosarcoma and endometrial carcinoma had increased serum IgM and numbers of spleen cells and complement receptor lymphocytes. No such changes were noted for mice that received transplants of malignant melanoma, In contrast, there were no apparent differences in the responses of nude mice, who were given transplants of human tumors, to be T-cell mitogens concanavalin A or phytohemagglutinin or in the number of theta-bearing spleen cells. The success rate for transplantation was significantly improved when explants, rather than single-cell suspensions, were performed. Tumors transplanted to nude mice derived from strictly homozygous matings behaved like tumors transplanted to mice born of heterozygous mothers. Finally, despite the dramatic size of subcutaneous tumor nodules, there were no examples of invasion or distant metastases.


Production of casein and the presence of estrogen receptors in human breast cancer.

The relationship between the presence of estrogen receptors and casein (evaluated on a semiquantitative basis with a specific immunofluorescence method) was statistically analyzed in 50 cases of human breast carcinomas. No significant correlation was found between these two parameters, whereas a relationship was established between the production of casein and the degree of histological differentiation. The results of this study, like those of other studies, revealed a lack of correlation between the presence of estrogen receptors and the degree of histologic differentiation.


Inhibition of effector cell function in human antibody-dependent cellular cytotoxicity by sera from cancer patients.

The effect of sera from 256 human cancer patients on the human antibody-dependent cellular cytotoxicity (ADCC) assay was studied. The cancer sera were compared to normal sera for their ability to alter the effector function of lymphocytes following 30 minutes' treatment at 37 degrees C. Even with this brief treatment, 74% of the 256 cancer sera inhibited effector activity. In most instances this inhibition was greater in patients with metastatic disease than in those without. Patients with colon and prostate cancer showed a statistically significant increase in inhibition among patients with disseminated disease (P less than 0.02 and P less than 0.01, respectively). An opposite effect was noted only in melanomas. It is suggested that the inhibition of the effector function in ADCC is a potential in vitro measure of the immunologic status of cancer patients.