A comparison of ventricular weights and geometry in newborn, young, and adult mammals. The weight of individual anatomic segments of the heart and calculated left ventricular chamber volumes have been studied in the hearts of 214 normal mammals of seven species (sheep, swine, dogs, cats, rabbits, guinea pigs, and rats). Comparisons have been made between newborn, young, and adult age groups. In addition, the heart weight-to-body weight ratio, percentage of right ventricular free wall weight in relation to left ventricular free wall weight (RVF/LVF), the relationship between calculated ventricular volume and weight and the left ventricular major minor axis ratios were examined in each age range. Heart weight (HW) in relation to body weight (BW) was greater in the newborn than adult in all species except the dog. HW/BW was twice as great in the adult dog as other species. In newborns RVF/LVF ranged from 55 percent in rats to 100 percent in puppies. Less species variation was present in adult hearts. Species with a more spherical adult LV configuration demonstrated a greater chamber mass-to-volume ratio. This may be attributable to greater wall tension.


Specificity of swim training on maximum oxygen uptake. The present study was designed to evaluate the specificity-generality of the cardiorespiratory adaptation to swim training. Fifteen male, college age, recreational swimmers utilized interval swim training procedures 1 h/day, 3 days/wk for 10 wk. Maximum physiological measures (Vo2, Ve, HR, R, and work time) were determined prior to and following swim training during treadmill running and tethered swimming Vo2max tests. Identical measures were made on 15 control subjects who did not participate in any form of training. As a result of training, the experimental subjects significantly increased (all P is less than 0.01) their swimming Vo2max (380 ml/min) max Ve (14.9 l/min,btps) and max swim time (4.0 min), and significantly decreased (P is less than 0.05) their max HR (3.5 beats/min). However, there was no significant improvement in Vo2max when the same subjects were evaluated by the treadmill running test. Differences in Vo2max and associated measures during running and swimming tests remained essentially unchanged for control subjects. The results of the present study clearly demonstrate the specificity of the cardiorespiratory adaptation to swim training in male recreational swimmers.


Ventilatory effects of hypoxia and their dependence on PCO2. In 11 healthy subjects the effect of progressive hypoxia on pulmonary ventilation at various alveolar carbon dioxide pressures was studied. A rebreathing technique was used to produce hypoxia, CO2 was held constant and oxygen saturation was taken as the independent variable. We found a linear relationship between ventilation and falls in oxygen saturation when Pco2 was held at the resting mixed venous, end-tidal, or any intermediate level. Within this range of Pco2, a family of ventilation-So2 response curves was obtained for each subject. The effect of altering the isocapnic level was to change the slope and position of the ventilation-So2 response curve, the amount by which the slope changed being related to the slope for that subject at their mixed venous Pco2.


Circadian variation of intercompartmental potassium fluxes in man. Circadian rhythms of plasma potassium concentration and urinary potassium excretion persisted in three normal volunteers when diurnal variations in activity, posture, and dietary intake were eliminated for 3-10 days. Measurements of the arteriovenous difference in plasma potassium concentration across the resting forearm and of erythrocyte potassium concentration suggested that there is a net flux of potassium from ICF to ECF in the early morning and a reverse net flux later in the day. The total net ICF-ECF fluxes were estimated from the diurnal variations in extracellular potassium content corrected for dietary intake and urinary potassium loss. The net fluxes between ICF and ECF were found to be counterbalanced by the circadian rhythm in urinary potassium excretion. Desynchronization of these rhythms would result in marked fluctuations in extracellular potassium content. These findings suggest that some revision is required of the concept of basal state in potassium homeostasis.


Influence of perfusion rate and compliance on esophageal manometry. The accuracy of esophageal manometry using the conventional perfused three-lumen catheter depends on the proper choice of the perfusion rate. Previous investigators have used a wide range of perfusion rates without considering the compliance of the transducer-catheter assembly as a variable in the selection of the perfusion rate for the hydraulic systems. We present a relationship relating the perfusion rate and the compliance which specifies the minimum adequate perfusion rate for a given transducer-catheter assembly. This approach explains apparent discrepancies in the literature regarding the proper rate of perfusion for accurate measurement of esophageal contractions. Esophageal motility tests with 10 subjects confirmed the accuracy of manometric tests at the prescribed perfusion rate (1.25 ml/min) since they compared well with intraluminal pressures measured directly with a Honeywell intraesophageal transducer. The effect of perfusion rate on the apmlitude of esophageal contraction was also investigated and it is shown that high perfusion rates result in increased amplitudes of contraction. Furthermore, at large perfusion rates a large volume of liquid builds up in the esophagus. This fluid accumulation could possibly be responsible for the increased amplitudes of contraction.


Selective parasympathectomy of the heart. Attempts to devise a chronic animal model with parasympathetic cardiac denervation have been complicated by early mortality due to pulmonary and esophagogastric dysfunction. By use of surgical techniques confined to the intrapericardial left atrium and immediately adjacent vena cava, selective cardiac parasympathectomy was performed on dogs. Verification of denervation was performed at the time of surgery by electrical stimulation of the cervical and thoracic vagi and stellate ganglia while recording blood pressure, ECG, and atrial and ventricular contractile force. Results demonstrate complete efferent parasympathetic denervation and abolition of the Bezold-Jurish reflex. Tachycardia at approximately 140/min was noted in all animals immediately and for several weeks postoperatively. No extracardiac complications were noted in any of the animals subjected to this procedure. Right heart catheterization of the conscious sedated dog revealed no evidence of right heart failure. Evidence of parasympathetic efferent reinnervation (sinus arrhythmia) was seen in some animals. This preparation should prove useful in studies of parasympathetic control of the heart, coronary vessels, and cardiovascular reflexes.


A stable, sensitive, low-compliance capacitance force transducer. The measurement of active and passive force levels in heart muscle requires short-and long-term base-line stability. The capacitance force transducer described here represents an optimization of the relationship between sensitivity, compliance, and frequency response in a design that minimizes long-term base-line drift related to thermal gradients within the apparatus. Thermal stability of the instrument is obtained with the use of quartz and Invar in the construction of the variable capacitor, the maintenance of internal transducer temperature at a constant level well above ambient, and the use of thermally insulating air gaps. Sensitivity ranges from 1.0 to 2.0 V/g wt in the several instruments tested, the output is linear, compliance is negligible with static loads up to 6 g wt, hysteresis is not significant with transient loading with 20 g wt, and long-term drift is greater than or equal to 0.050 g wt. These instruments are designed for use with myocardial preparations but can be adapted for skeletal muscle experiments.


Peripheral vascular response to norepinephrine at temperatures from 2 to 40 degrees C. The response to norepinephrine (NE) was studied in the perfused whole vascular bed and perfused arteries in situ and on helical strips of arteries and veins from the isolated duck leg. NE consistently produced vasoconstriction but the sensitivity was 3-50 times greater in the whole vascular bed than in artery segments. The drug effect was maximal at temperatures near 25 degrees C and diminished considerably at low temperatures (2-5 degrees C). Isolated helical strips of arteries and veins, when exposed to NE, showed maximal developed force at 25-30 degrees C. Tibial vessels developed only slight force at 5 degrees C while the tarsal-metatarsal and digital vessels responded even at 2 degrees C. The sensitivity to NE of both vessel types from the same region was similar. Flow in whole vascular bed perfused at constant pressure (40 cmH2O) was maximum at 30-35 degrees C. At both higher and lower temperatures flow declined and was about the same at 2 degrees C as at 40 degrees C. Our findings indicate that the vasoconstrictor effect of NE is exerted on both large and small veins and arteries; yet peripheral vessels respond more than do proximal segments at low temperatures. These findings suggest that peripheral vascular compartments may be capable of regulating regional blood flow at temperatures approaching freezing.


Myocardial and total body extractions of radiorubidium in anesthetized dogs. Myocardium (EM) and average total body (ETB) extractions of 86-Rb were determined in 24 anesthetized, open-chest dogs. Blood from the coronary sinus and from the pulmonary artery reflected the uptake of 86-Rb by myocardium and the total body, respectively, and extractions were computed from the relative arteriovenous differences (A-V/A). While the arterial concentration of 86-Rb was constant, EM varied from 0.66 plus or minus .02 (SE) at 2-2.5 min to 0.65 plus or minus 0.02 at 5-5.5 min, and ETB varied from 0.63 plus or minus 0.01 to 0.58 plus or minus 0.01 over the same interval. Mean extractions were similar statistically at 2-2.5 min, but individual differences as great as 30% were encountered at the 95% confidence level. After 3 min of 86-Rb administration, EM significantly exceeded ETB (P is less than 0.05) due to the more rapid decline with time of ETB. The similarity of the early extractions of 86-Rb by myocardium and by the total body supports, in general, the use of the radiorubidium uptake method for measuring coronary blood flow. However, the administration of the indicator should be brief, and rather large errors in individual estimates must be anticipated.


Effect of added elastances on the first loaded breath in man. Tidal volume together with end-inspiratory pressure was measured in four seated healthy men, during normal breathing and during single inspirations taken from a series of rigid containers which provided added elastances (range: 5-70 cmH2O/l). Experiments were performed both during quiet breathing and during ventilation increased by added dead space. Added elastic loads always resulted in a decreased tidal volume. This decrease was partly compensated by increased pressure developed by the inspiratory muscles; being more so with greater added elastance, control ventilation, or both. Analysis of our results indicates that the load-compensatory response may be attributed to changes in mechanical impedance of the ventilatory pump, due to the mechanical arrangement and the intrinsic properties of the inspiratory muscles (force-length and force-velocity relationships), changes in respiratory frequency with increasing ventilation, and to vagally mediated load compensation.


Energy cost of square dancing.

Energy cost of square dancing. This experiment was concerned with determining the energy cost of two popular Western square dancing routines: the "Mish-Mash," which is a relatively fast-moving dance with quick movements, and the "Singing" dance, which is a slower and more deliberate type of dance. The subjects were four middle-aged couples, veteran members of a local square dancing club. Sitting and standing pulmonary ventilations were determined through the use of the Tissot gasometer. Kofrańyi-Michaelis respirometers were employed for the dance routine ventilations. These apparatus were fitted with a Monoghan neoprene cushion plastic mask. Gas samples were collected in polyethylene metallized bags and analyzed for O2 and CO2 content. The net energy cost for the two dances was appropriately summarized. The results indicated that for the males the net average energy cost of the "Mish-Mash" dance was 0.085 and 0.077 kcal/min per kg for the "Singing" dance. For the females, the cost was 0.088 and 0.084 kcal/min per kg, respectively. A net average cost of these two dances yielded a caloric expenditure of 5.7 kcal/min for a 70-kg male and 5.2 kcal/min for a 60-kg female. It was indicated that during the course of a typical square dance evening, a 70-kg man would expend some 425 kcal. while a 60-kg female would burn some 390 kcal. The energy cost of the dances studied were determined to be within the permissible work load of a functional class 1 patient with diseases of the heart as determined by the American Heart Association.


Effects of atropine on natural deflation flows and P-V curves of the isolated lung lobe. Static pressure-volume (P-V) curves and natural deflation flows (NDF) in isolated dog's lung lobes were obtained before and after atropine. Since elastic pressure was the driving force for the expiratory flow this preparation was devoid of the influence of compressive forces. A significant shift to the left of the P-V curve was observed after atropine. Mean increase in volume in the range from 30 to 2 cmH2O transpulmonary pressure (Ptp) was 0.6 ml/g (about 4% increase in percent of maximal lung volume MLV). NDF at the same Ptp (referred to as airway conductance) were significantly higher after atropine (mean increase 3 ml/s per g, about 0.15 l/s). Increase in lung volume after atropine was interpreted as evidence of relaxation of residual bronchomotor tone which in turn, by increasing airway diameters, may produce higher flows. When NDF were plotted against volume, differences between control and atropine were reduced. This was attributed to the observed leftward displacement of the P-V curve. The linear relationship found between NDF and volume in the range 2-8 cmH2O of Ptp (about 35-75% MLV) suggests a proportionate change in airway conductance with lung size. This could indicate that the lobes behaved homogeneously during passive deflation. This pattern was not modified by atropine.


Effects of changes in PaCO2 on pulmonary input impedance. Pulmonary arterial input impedance spectra were computed in goats in whom the appropriate pressure and flow transducers had been chronically implanted. In response to either hypocapnia or hypercapnia, under anesthesia (1% halothane in a 70% nitrous oxide--30% oxygen mixture) there were no significant modifications of impedance at zero frequency; no consistent or significant changes in the impedance moduli at frequencies between 2 and 14 Hz were observed; the position of the first impedance minimum or the subsequent maximum was not modified; however, pulmonary vascular resistance increased significantly with hypercapnia. Although the load opposing right ventricular ejection was not modified by variation of Paco2, right ventricular work was reduced in response to hypocapnia and augmented in response to hypercapnia.


Forearm blood flow during body temperature transients produced by leg exercise. Subjects exercised for 30 min on a bicycle ergometer at 30, 50, and 70% of maximal aerobic power in ambient temperatures of 15, 25, and 35 degrees C and vapor pressures of less than 18 Torr. Exercise was used to vary internal temperature during an experiment, and different ambient temperatures were used to vary skin temperatures independently of internal temperature. Forearm skin temperature was fixed at about 36.5 degrees C. Esophageal temperature (Tes) was measured with a thermocouple at the level of the left atrium, and mean skin temperature (Tsk) was calculated from a weighted mean of thermocouple temperatures at eight skin sites. Forearm blood flow (BF) was measured by electrocapacitance plethysmography. Our data are well accounted for by an equation of the form BF = a1Tes + q2Tsk + b, independent of exercise intensity, although some subjects showed an equivocal vasodilator effect of exercise. The ratios a1/a2 (7.5, 9.6, 11.7) are quite similar to the ratios (8.6, 10.4) of the corresponding coefficients in two recent models of thermoregulatory sweating.


Role of inertia in the measurement of dynamic compliance. Dynamic compliance (Cdyn) was measured at different frequencies (breaths/min) in 30 nonsmoking males and females aged 30-59 yr. In those aged 30-49 yr Cydn at 90 breaths/min was significantly higher than at 15 breaths/min while those aged 50-59 yr showed no significant difference. Assuming an inertance of 0.01 cmH2O/l per s-2, and a sinusoidal breathing frequency, Cydn at 60 and 90 breaths/min was corrected for inertia. In the 30-49 yr age group corrected Cydn did not change with increasing frequency of breathing whereas in the 50-59 yr age group Cydn at 15 breaths/min was significantly higher than at 90 breaths/min (P is less than 0.05). In this age group, four of eight subjects were frequency dependent when corrected for inertia. These findings indicate that inertia influences Cydn at breathing frequencies of 60 per min and above. Unless this is taken into account, frequency dependence of compliance may be missed. The results also indicate that frequency dependence of compliance is normal in some older individuals but is not normal in the younger age group.


Glucagon and plasma catecholamine responses to graded and prolonged exercise in man. Eight men were studied during graded (47, 77, and 100% of maximal oxygen uptake) and prolonged (76%) exhaustive treadmill running. During graded exercise the glucagon concentration increased 35% from 81 plus or minus 7 pg/ml (mean and SE) at rest to 109 plus or minus 17 after the heaviest load. During prolonged exercise glucagon increased progressively to three times (226 plus or minus 40) the resting value. Norepinephrine increased from 0.40 plus or minus 0.06 ng/ml to 2.22 plus or minus 0.39, epinephrine from 0.07 plus or minus 0.01 to 0.42 plus or minus 0.13 during graded, and to 1.51 plus or minus 0.08 and 0.33 plus or minus 0.04, respectively, during prolonged exercise. Insulin concentrations were depressed during work except for the heaviest load. Fatty acids rose throughout prolonged exercise, whereas blood glucose significantly diminished 30 min afterward. Glucagon concentrations correlated significantly with norepinephrine and epinephrine concentrations during prolonged and with epinephrine during graded exercise. Although increments in catecholamines were similar, the glucagon secretion was larger during prolonged than during graded exercise. While increments in catecholamines might explain increased glucagon secretion during graded exercise, they cannot account completely for the rise of glucagon during prolonged exercise.


A theory of aerosol deposition in the human respiratory tract. The deposition of inhaled aerosol particles in the human respiratory tract is due to the mechanisms of inertia impaction, Brownian diffusion, and gravitational settling. A theory is developed to predict the particle deposition and its distribution in human respiratory tract for any breathing condition. A convection-diffusion equation for the particle concentration with a loss term is used to describe the transport and deposition of particles. In this equation, an apparent diffusion coefficient due to the velocity dispersion in the lung is present and found to be the dominant diffusion mechanism for the cases considered here. Expressions for deposition by various mechanisms are also derived. The governing equation is solved numerically with Weibel's lung model A. The particle concentration at the mouth is calculated during washin and washout and compared favorably with experimental recordings for 0.5-mum diameter di(2-ethylhexyl) sebacate particles. The total deposition in the lung for particle size ranging from 0.05 to 5 mum is also computed for a 500-cm-3 tidal volume and 15 breaths/min. The results in general agree with recent measurements of Heyder et al. However, a particle size of minimum deposition is found to exist theoretically near 0.3 mum.


Aging, isometric strength and endurance, and cardiovascular responses to static effort. Previous studies on the relationship of age to isometric muscular strength are few, on isometric endurance rare, and on the physiological responses to static effort nonexistent. This investigation assessed the maximal handgrip strength, the duration of a fatiguing handgrip contraction at a tension of 40% of maximal strength and the heart rate and blood pressure during that contraction of 100 men aged from 22 to 62 yr. The subjects of this study were all men employed in a machine shop for a large aircraft corporation. The homogeneity of their occupations may well explain why, unlike previous reports, we found no change in muscular strength or muscular endurance with age. However, although heart rate increased during the contraction in all subjects, the increase in heart rate was greater in younger men. In contrast, while both systolic and diastolic blood pressures increased during the contraction in all subjects, the largest increase in systolic blood pressure was attained by the men in the older decades; there was no difference due to age in the diastolic blood pressures. The implications of these findings are discussed.


Mechanical properties of the lungs and experimental asthma in conscious allergic dogs. Three allergic dogs were trained to swallow an esophageal balloon, breathe through a tracheostomy tube, and stand quietly in a wooden stall. The mechanical properties of their lungs were measured reproducibly over many months. Average values were: pulmonary resistance 1.33 cmH2O/l per s, static lung compliance 104 ml/cmH2O, and functional residual capacity 982 ml. In two dogs inhalation of histamine aerosol caused a 374% increase in resistance; inhalation of Ascaris suum aerosol caused a 307% increase in resistance. The increased resistance was associated with mild-to-moderate respiratory distress and slightly increased functional residual capacity. Aerosols of isoproterenol or atropine sulfate inhibited the increased resistance. We conclude that the conscious allergic dog is a suitable subject for the long-term study of asthma. Our present results are consistent with our earlier findings in anesthetized dogs, that a vagal reflex is involved in acute bronchomotor responses to inhalation of histamine as well as specific antigen.


Variant HeLa cells selected for their resistance to ouabain. The cardiac glyoside, ouabain, normally kills HeLa cells at concentrations of about 10-7 M or greater. By treating a population of HeLa cells with increasingly higher concentrations of the drug, a vaiant population was obtained of HeLa cells capable of growing in medium containing 10-4 M ouabain. Inhibition of volume regulation of cells subjected to hypotonic shock was used as a measure of inhibition of active transport of Na across the plasma membrane. In that way of dose-response curves for the rapid effects of ouabain and other inhibitors of active Na transport were obtained with both the original, ouabain-sensitive (OS) and the variant, ouabain-resistant (OR) cells. Three other cardiac glycosides (digoxin, digtoxin and hellebrin) and two aglycones (digitoxigenin and strophanthidin) were found to be equally as effective as ouabain in inhibiting volume regulation of the OS cells; the concentration whichproduced half-maximum inhibition, I(max/2), was about 6X 10-7 M in each case. Similar inhibition of the OR population by ouabain was observed only when the concentration exceeded 10-4 M [I(max/2-2.5 X 10-4 M], and the other steroid compounds had no effect on the variant cells at the highest concentrations tested (-2 X 10-5 M). OR and OS cells different also in their sensitivities to its cardoactive erythrophleum alkaloid, coumingine; I(max/2) for OS and OR cells was 5 X 10-8 M and 6 X 10-7 M, respectively. These results in addition to results of ouabain binding experiments and measurements of the rates of reversal of inhibition of volume regulation, suggest that a major reason for the differential sensitivities of the two phenotypes to these drugs is different affinities of their sodium pumps for inhibitors of active transport.


Slow phase hemolysis in hypotonic electrolyte solutions. When a population of erythrocytes is partially hemolyzed the time course of hemolysis can be divided into a fast phase and a slow phase. The slow phase occurs with both rapid and gradual addition of the hypotonic medium (rapid and gradual hemolysis). There is no difference in the osmotic fragility of erythrocytes remaining at 60 minutes after rapid or gradual hemolysis. Erythrocytes near their critical hemolytic volume have an equimolar ouabaininsensitive sodium-potassium exchange. Critical non-hemolytic swelling with resulting stress on the membrane appears requisite to slow phase hemolysis since more non-penetrant sucrose is required to prevent slow phase lysis rather than that which would be predicted from the intracellular colloid osmotic pressure due to hemoglobin. Sucrose protection from slow phase hemolysis thus depends not only on counter-balancing the colloid osmotic pressure, but also removal of sufficient intracellular water to prevent critical membrane strain. This model is consistent with that proposed by Katchalsky. Irreversible membrane changes associated with hypotonic stress manifested by persistent stomatocytic shape change and membrane wrinkling on return of cells to isotonicity appear to be due to critical changes in membrane components. Such cells, having normal indices and specific gravity are less deformable than control cells in 2.8 mum pore size polycarbonate filters.


Five fluorocarbons for administration of aerosol bronchodilators. The exposure of the upper respiratory tract to aerosol propellants produces apnea, bradycardia, and biphasic fall and rise in aortic blood pressure in anesthetized dogs. This response represents the irritation of sensory receptors in the nasal and nasopharyngeal mucosa and is not elicited with aerosol propellants administered via a tracheal cannula bypassing the upper respiratory tract. When this is done, a different reflex is elicited, consisting of tachycardia that is mediated by the thoracic sympathetic nerves. There is either bronchodilation or bronchoconstriction depending on the type of propellant. The three propellants (11, 12, and 114) widely used in aerosols, when inspired in large doses, elicit both bradycardia and tachycardia and induce bronchoconstriction or bronchodilation. Two additional propellants (115 and C318), which are not ordinarily used to dispense bronchodilator drugs, do not elicit any change in heart rate and produce only bronchodilation. It is suggested that these two propellants merit further investigation and may replace the three widely used ones if these prove the use and abuse of aerosols.


Small airway obstruction in allergic rhinitis. Applying newer techniques to assess the reactivity of small peripheral airways, we studied the effects of saline and methacholine inhalation in patients with allergic rhinitis. The maximum midexpiratory flow rate (MMF) and the maximum terminal flow (MTF) were used to assess the degree of small airway obstruction. Four rhinitis patients (13 per cent) had abnormal baseline MMF and/or MTF and 12 patients (38 per cent) developed a decrease in MMF and/or MTF after saline inhalation. Twenty-one patients (66 per cent) responded to methacholine inhalation with a greater than 20 per cent fall in the MMF and/or MTF. This response was significantly different from that of the control subjects (p less than 0.01). The patients' hyperresponsiveness appears to be similar to that of asthmatic patients except that the obstruction is primarily limited to the airways.


Dietary standards.

Dietary standards. There are two primary purposes and uses of dietary standards--the planning of diets or food supplies and the evaluation of dietary histories. It is argured that no single set of dietary standards can adequately fulfill both functions. The design of diets requires considerations other than estimates of nutritional needs--food supplies, food habits, and so forth--and must ordinarily provide the needs of groups ofmixed age, sex, and activity.  Standards based on nutrient density may be the most useful for this purpose.  The evaluation of the nutritional adequacy of foods eaten must be based on estimates of nutritional need. How, in applying, such standards, consideration must be given to the variability in nutrient intake from day to day. Current methods of evaluating dietary data inevitably overestimate the number of individuals at risk of nutritional deficiency.


Nutritional status of black preschool children in Mississippi. Influence of income, mother's education, and food programs. The nutritional status of 247 black preschoolers in two counties of Mississippi was studied by relating caloric and nutrient intakes and anthropometric measurements to homemaker's education, family income, and participation in Food Stamp and donated food programs..23AUTHOR Low intakes of calories, iron, calcium, vitamin A, and ascorbic acid were found in many of the children, regardless of the variable considered. These findings--in comparison with similar studies--imply that, as time passes, low education and income are having less impact on child nutrition. This ameliorating effect may be due to programs designed to educate parents and extend purchasing power of food dollars. Thus, it seems advisable to continue these programs.?23AUTHOR


Nutritional knowledge, attitudes, and practices of high school graduates. A mail survey was conducted to investigate the relationship between previous nutrition education in high school home economics classes and the present nutritional knowledge, attitudes, and practices of Ohio high school graduates. Findings revealed that young women previously enrolled in home economics courses with a unit in food, nutrition, and health did not achieve significantly higher scores in tests of nutritional knowledge, attitudes, and practices than did those who had not been exposed to such nutritional education. Attitudes toward food and nutrition were found to mediate the nutritional knowledge and practices of these high school graduates.


Lipid analysis of a frozen egg substitute. The lipid composition of an egg substitute and fresh eggs was conpared. The total lipid was divided into fractions on a silicic acid column. Thin-layer-chromatographic analysis demonstrated that the egg substitute was practically void of cholesteryl esters. Gas-liquid-chromatographic analysis were used to ascertain the fatty acid composition of the various fractions. Eggs contained considerably higher concentrations of saturated and mono-unsaturated fatty acids than did the substitute. The polyunsaturated fatty acid concentration in the substitute was approximately three times that of eggs. In all fractions, the eggs contained several more individual fatty acids than did the egg substitute.


Personal history and job tenure of dietary employees. Possible relationships of six personal characteristics reported on application blanks and job tenure of hospital dietary employees were statistically analyzed. By chisquare analysis, three characteristics--age (forty-six years or older), marital status (widowed or divorced), and education (less than nine years)--appeared to be positively related to longer tenure (over six months). However, multiple regression analysis to determine the combined effect of all variables indicated no relationship which could be used to predicting tenure when employing dietary workers.


A decade of Dial-a-Dietitian in Columbus, Ohio. Data gathered during the decade 1962-1972 on Dial-a-Dietitian as a community service of the Columbus Dietetic Association support the usefulness of this unique experiment in community nutrition education. The image of the dietitian as a spokesman for the science of nutrition and as a contributing member of the health team should be advanced in every way possible. Dial-a-Dietitian is a realistic vehicle which offers much needed assistance. There emerges the need for individualized diet counseling with a fee-for-service and referral from the physician or dentist. Dial-a-Dietitian might then be in a position to direct its enery and resources toward better serving community needs with respect to normal nutrition education. District dietetic associations should define and redefine the objectives to be served by the Dial-a-Diettian program as these relate to specific and changing requirements.


Ultrastructural studies of keratinized epithelia of the mouse. III. Determination of the volumes of nuclei and cytoplasm of cells in murine epidermis. Simple morphometric analyses were applied to mouse epidermal specimens prepared for electrom microscopy. Mean values were obtained for the dimensions of cells and nuclei in basal, suprabasal, and granular layers. These measurements were applied to simplified models representing the shapes of cells in the three strata. A fourfold increase in cytoplasmic volume was observed as cells passed from the basal to granular layers. During this transition, the nuclear volume did not decrease significantly.


Secretion from human apocrine glands: an electron microscopic study. Electron microscopic examination of apocrine glands revealed three types of secretion: merocrine apocrine, and possible holocrine. In the merocrine type of secretion numerous vesicles originating in the Golgi area discharged their granular contents into the lumen of the gland. In the apocrine type of secretion three stages were observed: (1) formation of an apical cap; (2) formation of a dividing membrane at the base of the apical cap; and (3) formation of tubules avove the dividing membrand that extended parallel to the membrane and led to a separation of the apical cap from the underlying cell, In the holocrine type of secretion individual secretory cells or even strands of secretory cells were dischard into the lumen of the gland.


Congenital circumscribed hypomelanosis: a characterization based on electron microscopic study of tuberous sclerosis, nevus depigmentosus, and piebaldism. Subcellular defects of hypomelanosis in tuberous sclerosis (TS) (28 subjects) were compared by light and electron microscopy with oThere forms of congenital circumscribed hypomelanosis that occur in nevus depigmentosus (ND) (8 subjects) and in piebaldism (PB) (4 subjects), respectively. On the light microscopic level in both TS and ND, the population density of functioning melanocytes was normal but each perikaryon was small, and dopa activity was decreased. On the ultrastructural level, the hypomelanotic skin and hair of TS were associated with a decrease in the synthesis, melanization, and size of melanosomes; the decrease in the size of melanosomes resulted in the aggregation of melanosomes (i.e., a melanosome complex) in the keratinocytes in all the specimens examined. In ND, ther were no obvious changes in the size and melanocytes. the hypomelanosis of ND is related to the decreased synthesis and also, perhaps, abnormal transfer of melanosomes. In PB the hypomelanosis of the skin and hair results from the absence of functional melanocytes. The hypermelanotic areas of PB, however, characteristically contain melanocytes that synthesize abnormal (sperical and granular) as well as normal (ellipsoidal and lamellar) melanosomes.


Morphometric evaluation of sebaceous gland volume in intact, castrated, and testosterone-treated rats. Starting a 19 weeks of age six male rats, castrated at 16 weeks, were injected intramuscularly three times per week with 0.25 mg testosterone propionate (dissolved in sesame oil) per 100 grams body weight. Four castrated control rats received sesame oil only. Samples of dorsal skin were taken under light ether anesthesia at the time of orchidectomy and at weekly intervals during treatment. Histologic sections were cut perpendicular to the skin  surface, stained with hematoxylin and eosin, and analyzed morphometrically for their volume content of sebaceous glands, A square grid of 42 sampling points was superimposed on each microscopic field at a maganification of 300X and an average of about 1000 points were counted over the entire thickness of the skin in each section. The average thickness of the skin was also determined for each sample. Three weeks after castration the mm-3 of sebaceous glands per cm-2 of skin was reduced from 1.76 to 0.96, a difference that is statistically significant at p is less than 0.005. One week after starting testosterone injections, the volume of sebaceous glands was more than double that in the control animals: 3.0 vs 1.2(p is less than 0.02). Even greater differences were found at 2 to 4 weeks of treatment.


Serum complement and immunity in experimental simian malaria. II. Preferential activation of early components and failure of depletion of late components to inhibit protective immunity. The role of complement in the control of parasitemia was examined. Depletion of late components (3-9) by cobra venom factor did not alter either the degree or course of parasitemia during the pre-immune or immune stages of infection. The pattern of consumption of complement components was therefore examined. Concomitant with schizont rupture there was depletion of early-acting components (C1, C4, and C2) of the clasical complement pathway. The magnitude and remporal relationships of the fall were similar for these three components. Serum levels returned to prerupture values over 36-48 hr, and then the cycle was repeated. There was no simultaneous change in the levels of C3, C3 proactivator, or C6. These results delineate a new pattern of cyclical consumption of early components of the classical complement pathway associated temporally with schizont rupture and suggest that the late-acting components are not required for protective host immunity in malaria.


Familial clustering of hepatitis B surface antigen among Panamanian Indians. Several authors have suggested that the host genome determines the occurrence of chronic HBS Ag (hepatitis B surface antigen). In attempts to evaluate this possibility, total infection rate and the combined frequencies of HBS Ag and antibody to HBS Ag and radioimmunoprecipitation to measure antibody to HBS Ag, we tested sera from 255 Panamanian Guaymi Indians. They represented 48 families and 32 living units. Clusters of chronically antigenemic individuals were found in families. Clusters of infection were not found in families or living units. Differences in family composition (age and sex) did not explain the increased occurrence of HGS Ag. These findings support the hypothesis that some humans have an inherited susceptibility to chronic infection with hepatitis B virus after exposure.


Normal and branched alkanes from cast skins of the grasshopper Schistocerca vaga (Scudder). Gas-liquid chromatographic and mass spectral analyses of the hydrocarbons from cast skins of the grasshopper Schistocerca vaga (Scudder) demonstrated the presence of four homologous series of alkanes: n-alkanes (35%), monomethylalkanes (24%), dimethylalkanes (35%), and trimethylalkanes (3%). The methyl branches were located towards the center of the molecule, and no 2- or 3-methylalkanes were detected by mass spectrometry. The branched alkanes occurred as isomeric mixtures with the methyl group(s) usually located on carbon atom 11, 13, 15, or 17. In the di- and trimethylalkanes, the branch points had isoprenoid spacing. Of the total hydrocarbons, the major component of the n-alkane series was nonacosane, 23%; of the monomethylalkanes, it was 11-, 13-, 15-, and 17-methylpentatriacontanes, 13%; of the dimethylalkanes, 9,13-, 11,15-, 13,17-, and 15,19-dimethylpentatriacontanes, 20%; and of the trimethylalkanes, 11,15,19- and 13,17,21-trimethylpentatriacontanes, 1%.


Enzymes of phospholipid metabolism in the plasma membrane of Acanthamoeba castellanii. Phospholipase A, lyophospholipase, acyl CoA hydrolase, and palmitoyl CoA synthetase are present in the plasma membrane of Acanthamoeba castellanii. The first three of these enzymes also occur in other cell fractions but in concentrations too low for the activities in the plasma membrane fraction to be accounted for by contamination by any other cell fraction. Palmitoyl CoA synthetase is restricted almost entirely to the plasma membrane and microsomal fractions; the microsomal activity is too low for the plasma membrane activity to be due to contamination by microsomes. Acyl COA:lysolecithin acyltransferase is predominantly localized in the microsomal fraction, but the activity of the plasma membrane is probably too great to be accounted for by microsomal contamination. CDPcholine:1,2-diglyceride cholinephosphotransferase is restricted almost entirely to the microsomal fraction. Phospholipase C was not detected in any cell fraction or in the growth medium.


Biosynthesis of digalactosyl diglyceride in Vicia faba leaves. Developing and mature leaf tissue from Vicia faba plants were pulse-fed 14-CO2. The lipids were extracted at intervals after exposure to light, and the galactolipids monogalactosyl diglyceride (MGDG) and digalactosyl diglyceride (DGDG) were separated. After methylation and methanolysis, gas-liquid chromatography was used to separate the two galactose units of DGDG and the galactose of MGDG. The specific activities of the galactoses and the changes over the time period of the experiment were determined. The results support the view that DGDG is formed by galactosylation of MGDG. This does not take place by a rapid two-enzyme system reaction but more slowly in two phases: galactosylation of a pool of newly formed MGDG and a more random galactosylation of MGDG. There is no evidence of a high turnover of galactose in these lipids.


Failure of the omnicardiogram to predict coronary artery disease in patients with normal resting electrocardiograms. Seventy-two male patients over the age of 35 had normal resting twelve lead eletrocardiograms (ECG's). All patients were studied by invasive techniques including complete right and left sided cardiac catheterization, selective coronary arteriography, and left ventricular angiography. All patients had been referred because of chest pain with a presumed diagnosis of coronary artery obstruction and myocardial ischemia. Omnicardiograms were generated from the twelve lead ECG's and diagnosed as "abnormal" or "normal" by observers having no knowledge of the cardiac catheterization findings. Of 72 patients studied, 21 were free of coronary artery disease. Of these, 14 (66%) had "abnormal" omnicardiographic reports. Seven (33%) had "normal" omnicardiograms, indicating an incidence of false positive "abnormal" omnicardiographic reports as 66%. Fifty-one patients had hemodynamically significant coronary artery disease. In this group, 19 (38%) were reported as "normal" by omnicardiogram, an incidence of false negative diagnosis of 38%. When the patients with coronary artery disease were classified as to single, double, or triple coronary obstruction, it was evident that the omnicardiogram had failed to separate patients with more extensive disease. Of the 32 patients with "abnormal" omnicardiograms, 56% had double or triple vessel disease, while of the 19 patients with "normal" omnicardiograph reports, 78% had double or triple vessel disease. Similarly, the omnicardiograms failed to identify the patients with abnormal left ventricular angiography. Of 19 patients with coronary artery disease and "normal" omnicardiograms, only 8 (42%) had normal ventricular angiography. However, of the 32 patients with coronary disease and "abnormal" omnicardiograms, only 11 (34%) had abnormal ventriculogram. The omnicardiogram cannot be considered a useful technique for predicting the presence or severity of coronary artery disease or for the identification of abnormal left ventricular function in patients with known coronary artery disease.


Origin of initial escape beat during graded vagal stimulation. Graded vagal stimulation was applied to the distal vago-sympathetic trunk in anesthetized dogs. The effects of vagal stimulation were expressed as cardiac delay time, which is specifically measured as the R-R interval of the asystolic period or bradycardial beat, minus the control R-R interval. Graded vagal effects were best obtained by stimulation with varying pulse duration at fixed voltage and frequency. As pulse duration was increased, progressive bradycardia and brief cardiac arrest occurred. With further increase in pulse duration, cardiac delay time increased markedly and remained essentially unchanged over a wide range of still greater pulse durations. ECG's recorded stimultaneously showed initial sinus bradycardia, atrial pacemakers and A-V junctional beats during brief cardiac delays. The initial escape beat following prolonged cardiac delay was always A-V junctional or ventricular ectopic in origin. It is concluded that the initial escape beat following prolonged cardiac delay arises from latent ventricular pacemakers not subject to vagal influence.


The quantitative effects of coronary-myocardial ischemia on the S-Q integrals of epicardial electrograms in the dog. The purpose of this study was to measure the relationship between quantitative changes in an epicardial electrocardiographic complex and times of total occlusion and reactive hyperemia in the coronary vessel that supplied the myocardium beneath the electrode. Fifty-six experiments were performed on 9 open-chest dog preparations in which the left anterior descending coronary artery had been cannulated and connected by tubing to the left carotid artery. The shunt was totally occulded for 5, 10, 30, 60 and 90 sec intervals and the sugsequent reactive hyperemia was recorded with an extracorporeal electromagnetic flowmeter placed in the shunt. Potentials from an epicardial electrode placed over the probable area of perfusion of the artery were recorded and analyzed by a digital computer. The integral of each beat from the S to the Q point of the ECG complex was computed. The total electrophysiological change from baseline thus quantified was found to be linearly correlated with the volume of flow deprivation during occlusion (perfusion volume debt) and the volume of reactive hyperemic repayment. The study substantiates experimentally earlier exercise studies of patients with ischemic heart disease in which changes in the SQ integral were found to correlate linearly with exercise intensity. The results support the hypothesis that quantitative measures of the electrocardiographic complex may be used to document the severity of ischemia in mammalian ventricles.


The influence of exercise on atrial flutter. To study the effect of exercise on atrial flutter the electrocardiogram was recorded continuously before, during and after low level treadmill walking in twenty-two ambulatory patients. Atrial flutter rates increased during exercise testing in four patients. Improved A-V conduction with consequent higher ventricular rates occurred during exercise in thirteen subjects. One patient, with 4:1 conduction at rest, continued with 4:1 block throughout exercise testing, was believed to be over-digitalized. During the recovery period after exercise, ten patients transiently developed periods of Wenckebach A-V block. Walking exercise induced 1:1 conduction in six patients and was promoted by the following circumstances: 1) atrial rates of 250/min or less; 2) inadequate dosage of digitalis; and 3) the administration of quinidine. For the patient with chronic atrial flutter, treadmill testing provides a simple method for demonstrating the range of changes of A-V conduction and for deriving implications for appropriate drug therapy.


Two-step electrocardiogram for chest pain reported on multiphasic screening. Among 264 consecutive persons (142 men, 122 women) greater than or equal to 35 years of age presenting for multiphasic screening examination, 85 (54 men, 31 women) reported chest pain. In most, the pain was not typical of coronary artery disease. The two-step exercise electrocardiogram (ECG) was positive (greater than or equal to 0.5-mm ischemic ST depression) in 21% of the patients who reported pain and in 19.5% of 66 randomly selected, similarly examined controls without chest pain (36 men, 30 women) (difference not significant). Females with positive ECGs (5-mm or 1-mm depression) predominated over males greater than or equal to 5:1 in the chest pain group and greater than 3:1 in controls. This study indicates that the routine two-step exercise ECG is not helpful in detecting ischemic heart disease in persons reporting chest pain during their multiphasic screening examination.


Wenckebach phenomenon within the atria.

Wenckebach phenomenon within the atria. A patient with a history of fainting and a bifacicular block (CRBBB plus LPH) was analyzed by His Bundle electrograms. During atrial pacing at a rate of 138/min, a Wenckebach type of block occurred within the atrium or at the electode-atrium junction, or both. The sinus intra-atrial conduction time (P-A inverval) was normal. During atrial pacing (pacing rate of 138 to 148/min), St-A interval progressively lengthened and ultimately a second degree Wenckebach type of block was obtained. The surface electrocardiogram (ECG) was normal and only electrical pacing brought on the intra-atrial conduction defect. Simultaneous with this atrial block, a second degree (Mobitz II) block developed.


Evidence for specialized atrioventricular conduction in hyperkalemia. A patient who had chronic coarse atrial fibrillation developed severe hyperkalemia accompanied by total loss of fibrillatory waves while an irregularly irregular ventricular rhythm persisted. Correction of hyperkalemia resulted in prompt return of coarse atrial fibrillation. This sequence of events renders strong support to direct atrioventricular conduction through the specialized internodal tracts.


An analysis of the circadian rhythmicity of atrial and ventricular rates in complete heart block. A 19 year old female human subject with complete heart block was put at complete bed rest for 63 hours during which a Lead II EKG was monitored at half hour intervals. Atrial and ventricular rates demonstrated cyclic activity with peaks during the day and troughs during the night. A correlation coefficient of plus 0.85 and a slope of plus 1.0 from a linear regression between atrial and ventricular rates demonstrated a close parallel. Calculation of the crosscovariances confirmed the observed cyclic activity with a period of 24 hours and phase angle of zero degrees between the two chambers. The data may be explained by one or all of the following mechanisms: (1) both chambers are subject to the same internal milieu, (2) autonomic nervous system discharge and associated reflexes may integrate relative changes in rate, (3) direct mechanical or electrotonic forces may result in alteration of rates in direct proportion to the magnitude of the dominant chamber, (4) program which operates independent of external factors. The question remains for direct experimental data to demonstrate whether the observed phenomenon is an intrinsic biologic rhythm within the heart or in its control system.


Idioventricular tachycardia with angina pectoris. Idioventricular tachycardia (IVT) occurred in a patient with angina pectoris on three separate occasions associated with stress induced angina. It occurred immediately after a Master's test, a treadmill exercise test, and following an episode of paroxysmal atrial tachycardia which was precipitated by endocardial pacing. His bundle electrograms demonstrated that the rhythm was ventricular in origin. Cardiac catheterization documented the presence of severe coronary artery disease. Idioventricular tachycardia is often seen with acute myocardial infarction. It is rarely seen with angina or with exercise testing. To our knowledge this is the first reported case of IVT which could be repeatedly produced by stress induced angina.


Therapeutic usefulness of chest wall stimulation in patients with demand pacemakers. Chest wall stimulation (CWS) has been used extensively to evaluate the performance of demand pacemakers. This brief report describes how this technique may also be used therapeutically in certain clinical circumstances.


Cell surface structure of rodent sperm heads. Replicas of critical point dried rodent sperm were examined by transmission electron microscopy. The surface of rat sperm heads appeared to be coated with regularly spaced 90A lamellar material. The plasma membrane overlying the acrosomal region of guinea pig spermatozoa displayed a regular scalloped array of lamellar structures. In replicas, the surface of Chinese hamster spermatozoa appeared coated by an array of small tubles and vesicles in the region overlaying the acrosome. It was possible to obtain replicas of the outer acrosomal membrane by removing the plasma membrane of mouse spermatozoa by brief treatment with Hank's balanced salt solution containing 0.2-0.5% MgC12. Replicas of the surface of the outer acrosomal membrane reveal evenly spaced, hexagonally-packed 90A particles similar to those which have been observed by other workers in replicas of freeze fractured outer acrosomal membranes. The finding of hexagonally arranged structures on the surface of the outer acrosomal membrane which appear very similar to those which have been observed in the plane of the membrane suggests that protein molecules in the plane of the membrane may protrude through or in some other manner distort the membrane surface. The post-acrosomal region of mouse sperm displays parallel lamellae with 100A spacing. If surface changes occur on sperm heads during maturation or capacitation, it should be possible to detect them with this technique.


Exogenous and endogenous control of the annual reproductive cycle in the male golden hamster: participation of the pineal gland. Testes and accessory sex organs (seminal vesicles and coagulating glands) of hamsters exposed to natural lighting (NL) conditions beginning September 22 underwent complete degeneration by October 31. The following February the testes began to regrow with the regeneration being complete by mid to late March. Associated with the atrophic response of the testes during the winter months was consistent depression in pituitary prolactin and an inconsistent decrease in pituitary luteinizing hormone levels. If hamsters are pineal lectomized prior to their exposure to NL, the sexual organs do not atrophy and the pituitary hormone levels do not drop. Moving hamsters from NL to the long daily photoperiods (light:dark cycles of 14 hrs light and 10 hrs darknessLD 14:10) of the laboratory near mid winter is followed by regrowth of the gonads and accessory glands. Regeneration of the reproductive system in the spring is not a function of increasing photoperiodic length since if animals are completely deprived of light (by blinding) in February, the gonads still regenerate. When hamsters are exposed to LD 14:10 cycles during the subsequent summer, the return to NL on September 22 is followed by a second involution of the reproductive system. However, if the period of LD 14:10 (the simulated summer) is shortened by ten weeks, the second return to NL does not initiate involution of the reproductive system. During the simulated summer complete light deprivation by blinding is incapable of forcing atrophy of the sexual organs.


Avian scale development V. Ultrastructure of the chorionic epithelium induced by anterior shank dermis from the scaleless mutant. In combination with dermis from the anterior shank skin of the scaleless mutant, the chorionic epithelium forms an epidermis whose ultrastructural features are indistinguishable from those seen along the inner surface of normal scales and along the anterior shank of the scaleless mutant.


Xenoplastic combinations between chick chorionic epithelium and fetal monkey dermis. Fetel monkey dermis from the sole of the foot or ear induces the chick chorionic epithelum (CE) to form an epidermis that histologically resembles chick rather than monkey. These results support the conclusion that in epithelial-mesenchymal interactions between animals of different vertebrate classes the epithelium responds in a species-specific manner. Differences were noted, however, in the response of the avian CE to either the sole or ear dermis.


Sex reversal in Betta splendens Regan with emphasis on the problem of sex determination. To gain insight into the sex-determining mechanism of the Siamese fighting fish, Betta splendens, sex-reversed individuals were bred and the ratios of the spawnings were examined. Sex-reversal of 245 females was undertaken by ovariectomizing them; of these, 104 became sex-reversed. Twenty-three of these latter fish were mated to normal females and eleven spawnings were raised to maturity. These spawnings resulted in all female broods or mixed broods. Were the male fish heterogametic, a view currently held by some authors, no males would be produced in these spawnings. Thus, male heterogamety was not substaintiated in this study. Contrary to other studies, the experimental sex reversal of females is not a rare event since nearly two-thirds of the fish that survived the surgery became sex-reversed. Gross dissection and histological observation of sex-reversed fish revealed a regenerated, unpaired duct which remained after the ovaries had been removed. The tissue of the regenerate was testicular and contained active spermatogenesis. Some alterative methods of sex determination which may apply to the Betta are examined. These include the possibility of two different sex-determining races, the effects of exogenous factors, and a polygenic system of sex determination.


The effects of epilation and hormones on the activity of rat hair follicles. The growth of hair from epilated and non-epilated areas of rats receiving a variety of hormonal treatments was investigaged by pulse-labelling with 35-S-cystine. While epilation at certain stages of the spontaneous cycle may rephase follicular activity, it did not affect the length, rate or duration of growth of the hairs which erupted subsequently, either in untreated or hormone-treated rats. Thyroxine shortened the active as well as the resting phase of the follicular cycle. It also increased the growth rate, so that hairs were ultimately the same length as those from untreated animals. Estradiol slightly shortened the duration of the active phase, even though the complete cycle was prolonged. It also decreased the hair growth. When administered simultaneously, estradiol and thyroxine exerted their effects independently.


The caecilian ear.

The caecilian ear. A study of the ear and its responses to acoustic stimuli was carried out in two caecilian species, Geotrypetes seraphini and Dermophis mexicanus. There is no external ear opening or tympanic membrane. The middle ear mechanism consists of a single element, the stapes, with its footplate in the oval window and a headpiece extending anterolaterally to the quadrate. The inner ear contains a single auditory endorgan, the amphibian papilla, somewhat similar to this organ in anurans. The mode of stimulation by sounds, however, involves a reentrant fluid circuit as in certain of the reptiles. In terms of the electrical potentials this ear is rather uniformly sensitive, though in low degree, to tones over the low-frequency range.


Dedifferentiation and mitotic activity in amputated newt tails locally deprived of the spinal cord (including a note on effects of amputation level on mitosis). The spinal cord of freshly amputated newt tails was displaced cranially by pushing several paraplast chips into the spinal canal with a glass needle. That part of the canal formerly occupied by the spinal cord was then packed with paraplast. Tails treated in this manner failed to regenerate, forming no more than a millimeter of new tissue with little or no cartilage and muscle. Dedifferentiation and early mitotic activity, however, was normal, indicating that the spinal cord exerts its effect on tail regeneration in the later stages. Amputation through the proximal region of a vertebra led to a significantly lower mitotic rate at four days than did amputation through the distal region, a situation contrary to the principle that during regeneration, elongation rate is gennerally faster from proximal than distal levels.


Neural correlates of associative training in Hermissenda. Hair cells in Hermissenda respond to illumination of the ipsilateral and contralateral eyes. These responses are modified by associative training of the animal. The observed electrophysiological changes appear to result from changes in the photoreceptors' synaptic input to the hair cells.


Techniques for termination of reverberating spreading depression in rats. Reverberation of cortical spreading depression (CSD) around a circular obstacle (thermocoagulation lesion) in the frontal cortex of anesthetized rats was elicited by appropriately timed and spaced applications of KCl. The probability of continued reverberation was increased by a pyrrolopyrimidine drug BW 58-271 (10 mg/kg) from 0.93 to 0.98. Three methods of reverberation arrest were tested: a) CSD propagation was blocked by an interfering CSD wave which was initiated in the rear of the reverberating wave, passing through a narrow segment of the circular pathway, and collided with the reverberating wave on the opposite side of the obstacle; b) CSD propagation through a part of the circular pathway was blocked by a 10-min application of 10% MgCl2 on the exposed cortical surface; c) 1-min asphyxia stopped RCSD by increasing the overall refractoriness of cortical tissue. Least reliable was the interference method which stopped reverberation, even with optimum timing, only in 42% of the trials. The magnesium blockade was reliable but slow, the reverberation stopping only 30 min after MgCl2 application. Asphyxia evoked in any phase of the reverberation cycle stopped RCSD reliably and immediately. The results obtained with the interference method confirm the predictions of the mathematical model of impulse reverberation in sheets of excitable tissue. Anoxia seems best suited for practical control of CSD reverberation in functional decortication studies.


Progression of partial experimental injury to peripheral nerve. Part 1: Periodic measurements of muscle contraction strength. Isometric measurements of muscle contraction in response to single as well as tetanic volleys of supramaximal stimuli were recorded from the limbs of 32 monkeys with noninjured or partially lacerated tibial nerves. Nerve action potentials (NAP) and muscle action potentials (MAP) were also determined at intervals varying from 1 hour to 52 weeks after injury. Limbs with mobilized noninjured nerve sustained small but definite decreases in muscle contraction strength particularly if the interval between operations was brief. Partially lacerated nerves had immediate averaged decreases in single twitch and supramaximal contraction strengths of 32.8% and 30.4% despite maintenance of NAP velocity. One week following injury, muscle contraction had decreased by another 21.6% and 19.7% respectively while NAP velocity was decreased by 18.5%. Measurements were also reduced at 2, 4, and 8 weeks and to a lesser degree at 12 weeks; at 24 and 36 weeks, muscle contraction was less than pre-injury data but not when compared to recordings 15 minutes after injury. Values recorded at 52 weeks reflected partial reinnervation of Achilles musculature. Studies over a 24-hour period following partial laceration demonstrated significant further decreases in muscle power by 8 hours. The authors conclude that nerve activity following partial laceration fluctuates as function diminishes during the early hours to weeks following injury.


Chronic subdural hematoma simulating transient cerebral ischemic attacks. Case report. A patient is presented in whom chronic subdural hematoma simulated transient ischemic attacks. The neurological manifestations were those of recurrent, transient episodes of expressive dysphasia preceded by focal sensory deficit. Various pathophysiological mechanisms which could have caused the unusual clinical picture are briefly considered.


Experience with a shunt system using the third ventricle. Technical note. The authors present a technique involving placement of a catheter in the third ventricle in shunt systems for hydrocephalus, in order to avoid obstruction of the proximal catheter by particles of chorioid plexus. They emphasize the simplicity of the technique, lack of morbidity, and the good results they have obtained in 30 cases with a follow-up from six to 40 months.


Modification of the Cushing speculum used for transsphenoidal pituitary surgery. Technical note. A modification of the original Cushing speculum used in the sublabial-transseptal-transsphenoidal approach to the pituitary is described. Although the modified speculum has smaller dimensions, it allows better visualization of the surgical field, while a new expanding device permits easier opening of the speculum.


Progression of partial experimental injury to peripheral nerve. Part 2: Light and electron microscopic studies. Biopsies from partially lacerated nerves were taken at the sites of proximal stimulus, laceration, and distal recording, and from stimuli and recording sites of control nerves. Electron microscopic examination of the partially lacerated major fasciculus revealed three zones of injury. The laceration zone showed neurotemetic changes, the adjacent or intermediate zone, partial degeneration, and the zone most peripheral to the laceration, changes in ground substance. Progression of the original injury is apparently due to ongoing changes in the intermediate and peripheral zones while much of the relative early recovery is due to reversal of changes in these zones. Regeneration through the laceration of neurotemetic zone is limited but does account for a small amount of late recovery of function.


Congenital scalp defects: aplasia cutis congenita. The authors discuss the rare lesion of congenital scalp defect, both partial and full thickness. The majority occur in children who are otherwise normal, but a few are seen in children who have many concomitant anomalies. A high percentage of the multiple anomaly cases were found to have trisomy 13-15. Etiology of these lesions is not clear, but there seems to be an inherited component. Treatment of otherwise normal children is conservative for the smaller lesions, with excision and primary closure when possible for the larger ones.


Acute subdural hematomas. Review of 144 cases. The authors report 144 cases in which acute subdural hematomas resulting from closed head injury were surgically treated. The mortality rate was 48% for those treated within 24 hours of injury and 45% for those treated within 72 hours. Patients under 10 years of age had a 33% mortality, while 69% of those over 60 years died. In the first 6 years of the series, 75% of the patients were treated by multiple burr holes and a subtemporal craniectomy, with a mortality of 41% in the last 6 years, 92% of the patients had large craniotomies with a 45% mortality. Of the 32 survivors among the last 60 patients treated, nine require full nursing home care, eight have returned to their own homes, 12 are able to care for themselves but not work, and three have returned to work.


Neurological and pathological effects of second lumbar spondylectomy and spinal column shortening in the dog. The second lumbar vertebra was surgically removed from 10 dogs, and the shortened vertebral column was stabilized by internal fixation with two types of plastic plates. Shortening of the spinal column was usually not associated with detectable loss of function or neurological deficit. Histological lesions, however, included widely disseminated axonal degeneration, gliosis, and atrophy of spinal nerve roots in the surgical area. The spinal cord adapted to shortening of the vertebral column by becoming intrinsically shorter, rather than be being displaced within the spinal canal.


Exposure of two interspaces for lumbar disc surgery. In a study of matched pairs of patients with a single ruptured disc, exploration of an additional lumbar interspace did not increase the morbidity of surgery. The author believes that the desire to avoid additional surgery does not, by itself, justify routine myelography.


Loss and recovery of vision with suprasellar meningiomas. Central visual acuity losses were documented in a group of 23 patients with surgically and histologically verified suprasellar meningiomas. The pattern demonstrated was that of acute, gradual or fluctuating loss in one eye, followed by later loss of central acuity in the other eye. Both optic nerves and chiasm were invariably involved either by stretching or compression. Neither preoperative field abnormalities nor central acuity deficits could be correlated with the anatomical location of the tumor, nor could postoperative changes in vision be correlated with tumor size. Lengthy duration of acuity loss and severe visual deficit did not preclude postoperative recovery of vision. Improvement in sight most frequently occurred within the first several weeks after operation, and further return of vision was not noted after 1 year.


Electrothrombosis of carotid-cavernous fistula. The author describes a technique for directly closing a carotid cavernous fistula with electrothrombosis while preserving the intracranial arterial circulation. Copper wires are introduced through the superior ophthalmic vein or a frontotemporal craniotomy, and thus directly into the portion of the sinus into which the fistula drains; if posterior, into the posterior segment of Parkinson's triangle, if inferior, into the pterygoid plexus, and if anterior, through the sphenoparietal sinus and/or middle cerebral vein to the anterior-inferior portion of the sinus. A direct current is applied until a thrombus is confirmed angiographically and the wires are left in place. Four patients treated by this method are presented.


Late results of radical excision of craniopharyngiomas in children. The results of radical surgical excision of craniopharyngiomas in children operated on by Dr. Donald Matson beginning in 1950 are presented. The patients are analyzed in regard to survival and quality of survival. While 22 of 34 children so treated at the initial operation are presently alive and tumor-free, high mortality and morbidity followed in cases where reoperation was performed. Properly treated endocrinological deficits need not be a serious problem, but persistent hyperosmolality carried a grave prognosis. No predictive criteria are yet available to determine which tumors are amenable to radical surgical excision.


Transfemoral embolization of an external carotid-cavernous fistula. Case report. The authors report a case of spontaneous carotid-cavernous fistula in which transfemoral arterial embolization under fluoroscopic control resulted in immediate occlusion of the fistula and dramatic resolution of the patient's signs and symptoms.


Interpretation of radionuclide liver images: do training and experience make a difference? Individual observers interpreted images in order to assess their accuracy and sources of error. Seventy-six liver images were presented to nine readers for interpretation. Readers of differing experience participated in the study: four radiology residents, three fellows in nuclear medicine, and two full-time nuclear medicine physicians. A higher incidence of false-positive reading was more common in inexperienced observers (11-50%) and the most correct readings were obtained by staff physicians (88% overall percentage accuracy). Heterogeneity in radionuclide uptake was the most frequently ill-defined nature was the most common false-positive finding in normal cases. Early stages of cirrhosis, mild hepatitis, and rare diseases such as hepatic sarcoidosis were difficult to detect. Skill of interpretation improved with experience, especially in judging heterogeneity of an ill-defined nature, and the rate of accurate readings was proportional to the level of training of the observer.


Radioiodinated fatty acids for heart imaging: iodine monochloride addition compared with iodide replacement labeling. Radioiodinated fatty acids have been proposed as agents for use in heart imaging. Previous studies in experimental animals and humans using 131I-oleic acid of low specific activity were marginally successful. Higher specific activity compounds offer potential improvement for use as imaging agents for normal myocardium. Methods for preparation of high specific activity, radioiodinated fatty acids by iodine monochloride addition to oleic, linoleic, and linolenic acids, and iodide replacement of terminal bromine in 6-bromohexanoic, 11-bromoundecanoic, and 16-bromo-9-hexadecenoic acids are presented and compared. Although both labeling procedures are suitable for use with 123I, the latter synthetic route gives labeled fatty-acid analog molecules and 16-iodo-9-hexadecenoic acid appears to show improved myocardial specificity in preliminary animal studies.


67Gallium in 68 consecutive infection searches. When employed in the study of peripheral infections, 67Ga scanning is sensitive and accurate. When used as a diagnostic tool for suspected abdominal abscesses, it locates and delineates abscesses in somewhat over half the cases. Moreover, the true-negative rate is high and the false-positive rate is acceptably low. Gallium scans should be interpreted with all available clinical information. The coexistence of noeplasm is a problem which at present is not completely resolved.


Clinical experience with 99mTc-DMSA (dimercaptosuccinic acid), a new renal-imaging agent. Results are reported from the clinical evaluation of a new radiopharmaceutical for renal imaging, 99mTc-DMSA (dimercaptosuccinic acid). Sixty-five patients were studied and six of these patients' scintiphotos are illustrated. The physical characteristics of 99mTc and the mercurial-like kinetics of the chelate produced high-resolution scintiphotos of the renal parenchyma in patients of all ages and with a variety of disease entities. The commercial availability of the material in kit form permits its usage in all nuclear medicine facilities.


Red cell and plasma volumes in normal adults. Despite numerous published methods for predicting normal red cell and plasma volumes, little is known of the range of normal in subjects of given body dimensions. In this study, reported results of red cell and plasma volumes in 481 normal men and 303 normal women have been used to calculate mean volumes and standard deviations (s.d.) for any given body surface area (male and female results being kept separate). All of these mean volumes, each plus or minus 2 s.d., have been plotted against body surface area. The resulting graphs of means and 95% confidence limits have tended to be curvilinear. Standard deviations have increased with increasing mean volumes, but coefficients of variation (s.d./mean) have shown considerable constancy at 11-12%. The mean values observed in this series have often differed substantially from those predicted from published formulas. Use of the presently observed means with the 11-12% coefficients of variation allows compilation for any surface area of a range of normal against which a clinically obtained volume can be compared.


Labeling of phagocytes from human blood with 99mTc-sulfur colloid. Experments in this report have shown that peripheral blood leukocytes can be readily labeled with 99mTc-sulfur colloid during in vitro incubation. Phagocytic cells were preferentially labeled by this method. Labeling was enhanced in the presence of normal serum. The data suggest that labeling was accomplished by phagocytosis of the radiocolloid. Labeled granulocytes responded normally to chemotactic stimuli and excluded trypan blue dye normally. Buffy coat cells from 50 ml of peripheral blood could be labeled with 8 mCi of 99mTc after incubation with 20 mCi of TcSC. This report offers a method by which phagocytic cells can be selectively labeled with 99mTc in amounts suitable for scintillation scanning.


Semiconductor camera for detection of small tumors. Early detection of small tumors (approximately 3 mm) with only a moderate uptake ratio is often difficult because of poor statistics and a small signal-to-background ratio. The detection capability of a germanium semiconductor camera is analyzed to show that a very large number of counts is required even when the spatial resolution is matched to the size of the tumor. A potential enhancement of statistics using the tissue-scattered gamma rays is discussed based on the superior energy resolution of the semiconductor.


An evaluation of 99mTc-sulfur colloid liver scintiscans and their usefulness in metastatic workup: a review of 1,424 studies. To determine the clinical usefulness of liver scintiscanning in detecting metastatic disease of the liver, 1,424 liver studies performed on 1,115 patients were reviewed along with their charts. Five hundred eighty-one patients had histopathological evaluation by needle biopsy of the liver, laparotomy, and/or autopsy within a mean period of 40 days of liver scan. The histopatholigical findings were correlated with the liver sicntiscan findings and the latter gave an overall accuracy of 77.3%.


Purification and radiochemical quality control of 131I-19-iodocholesterol. Radiochemical quality control and purification techniques were developed for 131I-19-cholesterol. The amount of ionic 131I-iodide is rapidly determined using instant thin-layer chromatography. Samples of the labeled steroid that contain greater than 8% of ionic 131I-iodide are purified with one of two techniques, both using a weakly basic ion-exchange resin. The first technique, a batch ion-exchange process, is suitable for removing relatively low concentrations of ionic 131I-iodide; if higher concentrations of this radiochemical contaminant are present, the second or column technique is more suitable.


Radioscintigraphic studies of 11C distribution in cats given 1-11C-ethanol. In vivo studies of 11C isotope distribution in cats given 1-11C-ethanol show accumulation of radioactivity in liver. Redistribution of radiolabel occurs after ethanol loading. Results indicate that some aspects of the matabolism of ethanol in specific tissues can be assessed by gamma-ray scintigraphy.


Uptake of radiolabeled estradiol by the canine adrenal. Tritiated estradiol injected intravenously into 11 mongrel dogs sacrificed at 3, 7, 10, 17, and 60 min showed maximum uptake in the adrenal gland at 3-7 min. The concentrations of radioactivity in the adrenal in percent dose per gram equaled that from 131I-19-iodocholesterol. If a 131I-estradiol could be synthesized that would concentrate similarly in the adrenal, it would offer the advantage of almost instantaneous imaging after the tracer injection and a lower radiation dose.


Three-dimensional reconstruction of lung perfusion image with positron detection. Transverse section images of the distribution of pulmonary perfusion in a canine have been obtained using microspheres labeled with the positron-emitting isotope 68Ga and a three-dimensional reconstruction technique. The reconstruction method is more accurate than conventional tomographic procedures and is facilitated by the use of positron detection. The transverse sections presented demonstrate the capacity of the technique to delineate reduction in regional perfusion resulting from occlusion of the artery to the left lower lobe.


Prostaglandins in mice with neuroblastoma. Male albino mice, with and without transplanted neuroblastoma C1300, had tissues analyzed for prostaglandins by radioimmunoassay. Highest prostaglandin concentrations occurred in tumor tissue, lungs, spleen, and kidneys. Tritiated prostaglandins A1 or E1 and tritiated arachidonic acid were injected intravenously. The concentration (organ/tumor) was higher at 1 hr than at 6 or 24 hr. Prostaglandin E1 and arachidonic acid localized principally in the kidney (likely the excretory organ) whereas prostaglandin A1 showed highest concentration in the liver.


Displacement of anterior cerebral vessels in cerebral dynamic study in cases of chronic subdural hematomas. About 75-80% chronic subdural hematomas give positive results in a brain scan. The typical scintigraphic finding of chronic subdural hematoma is a diffuse widening and increase of the peripheral activity on the anterior view. In the flow studies subdural hematomas lead occasionally to peripheral activity defects. In two cases of chronic subdural hematoma without typical patterns in a perfusion study as well as in static images, we found a displacement of the anterior cerebral vessels as an indircet sign of space occupation.


Sinusitis demonstrated by brain scanning. Increased concentration of technietum was noted in the region of the frontal, ethmoidal, and maxillary sinuses of two patients. Radiographs of the sinuses revealed extensive sinusitis involving the sinuses in the area of increased uptake. The increased uptake was attributed to the sinusitis.


Increased uptake of 99mTc-sulfur colloid in vertebral compression fractures. Increased uptake of 99mTc-sulfur colloid in vertebral bodies of two patients with vertebral compression fractures was noted on a liver-spleen scan. This finding has not previously been reported in the literature. The mechanism of localization of 99mTc-sulfur colloid in bone marrow depends on regional blood flow and increased reticuloendothelial and phagocytic cell activity. Both mechanisms are felt to be involved in these cases. In fractures, hyperemia and phagocytic activity are transient phenomena and therefore the above observations may be useful in determining fracture age.


High temporal resolution ECG-gated scintigraphic angiocardiography. The cardiac blood pool is visualized with high temporal resolution during a complete, average, cardiac cycle. The technique yields both qualitative and quantitative measures of cardiac performance.


A bone calcium index based on partial-body calcium measurements by in vivo activation analysis. Measurements of partial-body calcium by in vivo neutron activation analysis have been carried out on normal and osteoporotic subjects. Based on measurements on 16 normal subjects (volunteers less than 55 years of age), a calcium index has been established that takes into account variation in skeletal frame size. On the basis of this index, all osteoporotic patients have bone mineral content less than any of the normal subjects. The normal calcium indices range from 0.9 to 1.2, and the osteoporotic indices ranged from 0.41 to 0.83. Thirteen of 22 volunteers over 55 years of age had calcium indices less than 0.9 in agreement with the expected loss of calcium with age. Measurements of total-body potassium were also made on these same subjects and the calcium/potassium ratios calculated. Although as groups the older volunteers and older osteoporotic subjects had mean calcium/potassium ratios similar to the mean for the normal subjects, the osteoporotic subjects under 55 years of age had a mean calcium/potassium ratio significantly lower, indicationg that for this latter group the loss in bone mineral was not associated with a corresponding loss in muscle mass.


Pharmacokinetics of radioiodinated streptokinase. The pharmacokinetics of radioiodinated streptokinase have been investigated in mice and dogs in order to explore further its potential usefulness as a radiopharmaceutical to detect thrombi and neoplasms. The purified streptokinase used in these studies showed no alteration in its physical or enzymatic properties following radioiodination. In the mouse, radioiodinated streptokinase accumulated rapidly in the liver and at 4 hr, large amounts of free iodine were detected in the plasma. The plasma clearance curve in dogs was biexponential showing that 70% of the protein-bound radioactivity was cleared with a half-life of 1525 min while the remaining 30% was cleared with a half-life of 6080 min. Seventy percent of the plasma radioactivity appeared as free iodine after 4 hr. No change in clearance was obtained by preloading animals with unlabeled streptokinase. Based primarily on the rapid plasma clearance, deiodination, and possible limitations of effectiveness of preloading with unlabeled streptokinase, the results of these studies are in accord with the conclusion that radioiodinated streptokinase may have restricted usefulness as a radiopharmaceutical for detecting thrombi and neoplasms. The full extent of its potential usefulness, however, awaits the provision of further in vivo and in vitro studies directed at testing a covalently modified enzyme that retains streptokinase activity but whose immunologic properties have been altered so that the enzyme is not as rapidly cleared from the plasma.


Production and characteristics of 125Xe: a new noble gas for in vivo studies. Radionuclides of the noble gases are extensively used to assess ventilation and blood flow in clinical and investigative studies. Xenon-133 is most commonly used but is not optimal for these in vivo studies. Xenon-125 has better physical characteristics and can be produced with a cyclotron by a 127I(p,3n)125Xe reaction; this reaction results in a maximum of 25 mCi/gm/cm2/muA-hr for 31-MeV protons. Under actual production conditions, 11 mCi/muA-hr were collected. Xenon-125 decays by electron capture with a 17.2-hr half-life and contributes less radiation per dose of radioactivity than 133Xe. The radiation dose to the lungs from 133Xe and 125Xe is 5.0 and 1.8 mrads/mCi-min, respectively. The radiation dose per usable photon for 125Xe is only 0.3 of 133Xe. The principal photons of 125Xe, 188 keV (55%) and 243 keV (29%), are more intense and are in an energy range that is more advantageous for imaging than the 81 keV (35%) of 133Xe. These physical properties of 125Xe result in better spatial resolution at the same information density and with less radioactivity administered to the patient. Phantom studies showed that 12.7-, 9.5-, and 6.4-mm lead bars were resolved with 125Xe using a 410- keV diverging collimator wheras only the 12.7- and 9.k-mm lead bars were resolved using 133Xe and either a 410-keV or 140keV diverging collimator.


Gallium gallbladder scanning in cholecystitis. Gallium has been shown to accumulate in metabolically active tissue including sites of infection. The purpose of this study was to evaluate gallium scanning in cholecystitis. Ten patients with cholecystitis were studied using conventional gallium scanning techniques. Five patients with acute cholecystitis showed intense gallium accumulation in the gallbladder area. One of five patients with chronic cholecystitis showed significant accumulation in the gallbladder. The limitations of this method are mainly the need for serial scanning to rule out gallium accumulation in the hepatic flexure of the colon and also the failure to detect consistently a chronically diseased fibrotic gallbladder. We conclude that gallium scanning of the gallbladder is an important adjunctive study in the evaluation of cholecystitis.


Thallium-201 for medical use. I.

Thallium-201 for medical use. I. Thallium-201 merits evaluation for myocardial visualization, kidney studies, and tumor diagnosis because of its physical and biologic properties. A method is described for preparation of this radiopharmaceutical for human use. A critical evaluation of 201Tl and other radiopharmaceuticals for myocardial visualization is given.


Thallium-201 for medical use. II: Biologic behavior. Thallium-201 has been evaluated for myocardial imaging by determining its distribution and assessing its imaging properties. Organ distribution with time was studied in goats, chosen for their large size and easy operability. Myocardial imaging was performed in living and sacrificed goats and also in two anesthetized dogs, without infarction. Infarcts were made by ligature at open chest surgery on the goats and the infarcts subsequently confirmed histologically. The myocardium of normal and infarced, young and old goats was cut into blocks and the isotope distribution measured and compared with that in the lungs, liver, spleen, and kidney in normal goats. The renal medulla-to-cortex concentration ratio in goats was studied and is approximately five. The heart uptake exceeds 3% for 100 min whereas contiguous organs have less than one-half of the myocardial concentration, and blood clearance is rapid. One problem may prove to be inhomogeneity of uptake of thallium in the "normal" myocardium, showing a standard deviation of 1u% in a young goat and 29% in an old goat. In view of the good myocardial uptake, however, this work strongly suggests the trial 201Tl in patients.


Chemical and biologic properties of 111In-phosphate for cisternography and glomerular filtration studies. Inorganic 111In-phosphate has been evaluated for cisternography in dogs, rats, and one human volunteer for chemical and biologic stability and renal clearance. It appears to be stable and to be completely cleared by glomerular filtration, suggesting its suitability for cisternography.


Diminished uptake of 67Ga-citrate in a case of pseudarthrosis. A 22-year-old man with pseudarthrosis and infection of the right hip was referred for a 67Ga-citrate scan. A striking decrease was seen in normal bone and soft-tissue uptake in the entire right leg compared with the normal limb. Aortic injection of 99mTc-labeled microspheres showed increased trapping in the region of the hip but contrast angiography was unremarkable. Despite clinical imporvement, 67Ga uptake by the right leg on a repeat scan did not return to normal. This case represents the first report of a "photon-deficient" body part on 67Ga scanning.


Growth rebound after termination of stimulant drugs. To explore further the report of an accelerated weight gain following termination of treatment with a stimulant drug, 66 biannual growth measurements were obtained from 1970 to 1973 on hyperactive schoolchildren who were receiving medication. All received either dextroamphetamine or methylphenidate during the school year; some also received it during the summer. The data revealed that those whose stimulant medication was terminated at the start of summer subsequently grew in weight and height at a significantly greater rate than those who continued to receive medication from June to September. In fact, discontinuance of the medication resulted in a growth rebound for this period which was 15-68% above the age-expected increment.


Patent ductus arteriosus complicating respiratory distress syndrome. PDA was diagnosed in 76 (19%) of 396 patients with RDS. Evidence of excessive pulmonary blood flow and CHF developed in 15 (20%). CHF was not recognized prior to 10 days of age in any patient. All 15 with CHF were initially managed medically. Seven improved; three died of other causes. Five patients who failed medical management were surgically treated; all survived operation, but only two were improved.


Mother-to-child speech at 2 years--effects of early postnatal contact. Ten primiparous mothers were randomly selected from two groups of women who had spent different amounts of time with their newborn infants. The speech behavior of the mothers in the two groups was compared while they were addressing their 2-year-old children in an informal play situation. Speech patterns of the mothers revealed that those who had been given extra contact with their infants during the neonatal period used significantly more questions, adjectives, words per proposition, and fewer comands and content words than did the control mothers. These observations suggest that the linguistic behavior of the young child may be shaped by hospital-care practices for mother and her infant.


Acute hemiphegia of childhood associated with Coxsackie A9 viral infection. A 16-mo-old girl is described with acute hemiplegia associated with virologic and serologic evidence of Coxsackie A9 infection. Possibilities of pathogenesis are discussed. It is suggested that the present hemiplegia may have been the result of a focal vasculitis due to Coxsachie A9 viral infection in the region of the middle cerebral artery.


Myocardial infarction complicating bacterial endocarditis in rheumatic heart disease. Report of a case and review of the literature. A case of rheumatic heart disease with massive myocardial infarction from coronary embolism complicating bacterial endocarditis is reported. The rarity of this complication in the pediatric age group as compared to the adult age group remains unexplained. Early recognition depends on serial electrocardiographic and enzymatic determinations.


The syndrome of multiple aucosal neuromas and medullary thyroid carcinoma in childhood. Importance of recognition of the phenotype for the early detection of malignancy. Recognition of the syndrome of OF MMN can identify individuals at risk for the early appearance of MTC. Three such patients are described. Each had the characteristic neuromas and facies, present since infancy. In each, MTC was found in childhood. In the last two patients, the diagnosis was made because of elevated serum CT concentrations. Venous drainage from the tumor, as well as tumor tissue itself, contained high levels of CT. Prompt recognition of persons with MMN is essential for proper investigation and treatment of the associated MTC.


Older paternal age and fresh gene mutation: data on additional disorders. Older paternal age has previously been documented as a factor in sporadic fresh mutational cases of several autosomal dominant disorders. In this collaborative study, an older mean paternal age has been documented in sporadic cases of at least five additional dominantly inheritable disorders; the basal cell nevus syndrome, the Waardenburg syndrome, the Crouzon syndrome, the oculo-dental-digital sysdrome, and the Treacher-Collins syndrome. It was also found to be a factor in acrodysostosis and progeria, suggesting a fresh mutant gene etiology for these two conditions in which virtually all cases have been sporadic and the mode of genetic etiology has been unknown.


The effect of HCG on testicular androgen production in adult men with chronic renal failure. In sixteen male patients undergoing regular haemodialysis of peritoneal dialysis for chronic renal failure, the testosterone levels were studied before and after treatment with HCG. Testosterone values before (186 ng/100 ml) and after (456 ng/100 ml) HCG were significantly lower than those for normal healthy males. The mean plasma dihydrotestosterone (5alpha-DHT) value of 11.5 ng/100 ml for the treated patients was significantly lower than that of 64 ng/100 ml for the control patients. With HCG, increments in DHT were recorded in three patients, and definite increments in testosterone were observed in six patients. The percentage binding and combining affinity showed little change due to HCG stimulation. Achieving ejaculation was a serious problem  for the patients in whom the lowest increases in testosterone and 5 alpha-DHT levels were observed after HCG stimulation. Low plasma testosterone values were also associated with a low mean area for Type-2 muscle fibres.


Variations in serum FSH, LH and testosterone levels in male rats from birth to sexual maturity. Serum LH, FSH and testosterone concentrations were measured by radioimmunoassays in male Sprague-Dawley rats from birth to 80 days of age. The levels of FSH were significantly elevated during the first 5 days of postnatal life. An abrupt decline in FSH concentrations occurred during this period, from levels of 800 ng/ml on day 1 to levels of 300 ng/ml on Day 6. Subsequently, FSH levels fluctuated widely until about Days 30 to 45, when a secondary peak of FSH was observed. Thereafter, a decline in FSH levels to those found in adult rats occurred. This decline in FSH levels appears to coincide with the first release of mature spermatozoa from the germinal epithelium in the testis. During the first 30 days of postnatal life, LH and testosterone values appeared to be inversely related to each other and an LH peak and a nadir of testosterone levels was observed between Days 6 and 14 at time corresponding to regression of the fetal generation of interstitial cells. A parallel rise in LH and testosterone levels occurred from Days 30 to sexual maturity and corresponded to the development of the adult generation of intestitial cells.


The effects of tubal ligation on ovum transport in rabbits. Ovum transport was studied in rabbit oviducts ligated 18 hr after mating in untreated and oestrogen-treated rabbits. Essentially all ova (93.5%) were recovered from the sham-ligated oviducts averaged 46.7%. Recovery of ova in oviducts ligated at the infundibulum and at the uterotubal junction was 100%. It is likely, therefore, that ova were transported prematurely into the uterus from ligated oviducts. Ovum transport through sham-ligated oviducts was significantly retarded by a single injection of oestradiol cyclopentylpropionate (25 or 250 mug) but remained accelerated in ligated oviducts diminished by 60 hr p.c. in untreated rabbits, but was maintained in oestrogen-treated rabbits. Ovum transport through distended oviducts may be accelerated by the passage of oviducal fluid into the uterus.


Radiation effects on testes. II. incorporation of 65Zn after partial body gamma-irradiation of rats. The decrease in the uptake of 65-Zn by irradiated testes (720 R) was followed by recovery after 30 days. After a dose of 2000 R, uptake of 65-Zn was systemtically reduced over a period of 74 days. Studies following the administration of testosterone and FSH germinal cells of the testes is under the control of pituitary gonadotrophins.