Use of circulating immune complex levels in the serodifferentiation of endocarditic and nonendocarditic septicemias.

Distinguishing endocarditic from nonendocarditic septicemias is prognostically and therapeutically important. One hundred two patients with both valvular and nonvalvular sepsis were studied for the presence and quantitation of circulating immune complexes. Ninety per cent of the patients with infective endocarditis versus 50 per cent of septic patients without infective endocarditis had circulating immune complex levels (p less than 0.005). Mean circulating immune complex levels in patients with infective endocarditis were significantly higher than in those without infective endocarditis, 106 +/- 18.58 microgram/ml versus 31 +/- 7.4 microgram/ml (p less than 0.005). Only three of 52 patients without infective endocarditis had circulating immune complex levels greater than 100 microgram/ml, as opposed to 16 of 50 patients with infective endocarditis (p less than 0.005). Similarly, one of 52 patients without infective endocarditis has circulating immune complex levels greater than 200 microgram/ml, as opposed to eight of 50 patients with infective endocarditis (p less than 0.05). In 92 per cent of the patients without infective endocarditis and 76 per cent of those with infective endocarditis peak circulating immune complex levels developed within 14 days after their entry into the study, often on the initial sampling. In febrile, septicemic patients with clinical symdromes nonclassic for endocarditis, measurements of serial circulating immune complex levels may be of adjunctive diagnosis importance. If circulating immune complex levels are undetectable, endocarditis would appear less likely; alternatively, levels above 100 to 200 microgram/ml would suggest a valvular rather than nonvalvular septic focus.


Clostridium septicum bacteremia. Its clinical significance.

The medical records of 59 patients with Clostridium septicum bacteremia were reviewed; 42 (71 per cent) of these patients had malignancies. One half had hematologic malignancies, and one half had solid tumors. Of the 21 patients with solid tumors, 14 (67 per cent) had cancer of the colon. Among these patients, the cecum was the most frequent site of malignancy. The cecum and distal ileum were the most probable portals of entry for C. septicum bacteremia among the 28 patients examined at autopsy. Patients admitted to the hospital with C. septicum bacteremia usually have fulminating clinical courses and, unless the appropriate antibiotics are administered soon after admission, the outcome is fatal. The results of this study demonstrate the high association of C. septicum bacteremia and malignancy, and the need for early recognition and therapy.


Clinical evaluation of netilmicin therapy in serious infections.

Netilmicin, a new semisynthetic aminoglycoside, was evaluated in the therapy of 33 episodes of infection in 30 patients. Eighteen patients had documented bacteremia. Infection sites included pulmonary, urinary tract and soft tissue areas. A complete bacteriologic and clinical cure rate of 85 per cent was achieved. No treatment failures occurred in the bacteremic group. Although netilmicin is less effective than gentamicin in vitro against Pseudomonas, it was clinically and bacteriologically effective. Netilmicin bacteriologic cures occurred in patients whose organisms were inhibited by 6.2 microgram/ml or less of netilmicin. Despite a uniform dosing protocol, a wide range of netilmicin serum levels was obtained. Adverse effects were limited to one case of transient nephrotoxicity and one Candida urinary suprainfection. Netilmicin appears to be an effective, safe agent for the therapy of serious infections.


Resettling mentally retarded adults in the community--almost 4 years later.

A cohort of 63 mentally retarded adults from three state schools was studied longitudinally for almost 4 years from the time they were resettled at a community residence in a large city. The purpose of the study was to determine whether changes in self-image, interpersonal relationships, work experience, use of leisure time, personal decision-making, and social competency would occur as a result of living in a new environment. Results of three interviews at different points in time were compared and presented by Birenbaum and Seiffer (1976). In the present study we compared results obtained through third- and fourth-wave interviews of 42 residents who remained at the community residence for almost 4 years. Respondents were found to maintain steady involvement in sheltered workshops and have some personal relations with peers, but they were less active participants in leisure activities in the community and more restricted in personal decision-making at home.


Relationship between community environments and resident changes in adaptive behavior: a path model.

The relationship between environmental ratings of community homes using factor scores derived from Wolfensberger and Glenn's Program Analysis of Service System (PASS) and changes in adaptive behavior of residents living in those facilities was investigated. A path analysis was used to relate resident characteristics, e.g. age, IQ, and initial score on adaptive behavior, with six PASS environmental ratings and both of these sets of variables with average annual change in adaptive behavior over a 3-year period. The results showed that a number of PASS scores were significantly associated with positive change in adaptive behavior for specified types of residents. The most general finding was that older, less retarded residents improved in all aspects of adaptive behavior in conjunction with positive ratings on items dealing with comfort and deployment of staff, access to the home, local proximity of services, and blending with the neighborhood.


Language differences between institutionalized and noninstitutionalized retarded children.

The linguistic performances of 15 noninstitutionalized and 15 institutionalized retarded children were compared on usage of grammatical categories and structure of spoken language (Length--Complexity Index) and for underlying subskills (Illinois Test of Psycholinguistic Abilities). Differences were not found between the groups for usage of grammatical categories or structures but were found for subskills of Auditory Reception. Auditory Sequential Memory, Verbal Expression, and Auditory Closure. Further analysis by multiple stepwise regression indicated that noninstitutionalized and institutionalized retarded children may be differentiated by examining a number of linguistic variables. The grammatical structure of language appeared less  affected by environment than were the semantic and auditory elements.


Imitation in EMR boys: model competency and age.

The effects of model age and competence on the imitation behavior of 80 EMR boys were investigated. Subjects viewed a videotape in which either an adult or a peer performed a motor task with either high or low competence. In addition, the models engaged in four different kinds of off-task social behavior. The results indicated that the boys imitated the off-task social behavior emitted by high-competent and peer models more than low-competent and adult models. In addition, high-competent models were imitated more than were low-competent models on the motor-skill task, but no significant age effect was found. The efficacy of modeling as an instructional strategy was discussed, and we concluded that EMR boys should be exposed to competent models, especially peers, who emit a repertoire of adaptive behavior.


Effect of labeling and teacher behavior on children's attitudes.

Seventy-eight fourth-grade subjects from a rural school containing an integrated special-education program viewed one of two videotapes that depicted a child demonstrating various kinds of academic and social behavior. On one tape, the teacher reacted positively to the child's behavior; on the other, negatively. The subjects were told that the child on the tape was either a "normal," mentally retarded, or learning-disabled fourth grader. The subjects were randomly assigned to one of two teacher conditions (positive or negative) and one of three labeling conditions. After viewing the videotape, the subjects filled out a peer-acceptance questionnaire concerning the child on the videotape. Results indicated that across all labeling conditions the subjects rated the child higher on the questionnaire when the child was reacted to positively by the teacher and, further, that the "mentally retarded" label led to significantly higher peer-acceptance ratings than did the "normal" or "learning-disabled" label.


Stress inoculation and interinstitutional transfer of mentally retarded individuals.

Forty-four mentally retarded individuals were studied to determine if relocation syndrome can be averted in interinstitutional transfer. Twenty-two persons who were transferred on a voluntary basis to a small, new, highly staffed facility and given individualized attention in preparation for the move were compared to a group of nontransferred matched control persons on the Progress Assessment Chart and the Maladaptive section of the Adaptive Behavior Scale, Which were administered prior to transfer and 1, 2, and 4 weeks after. The transferred group displayed no lowered functioning in adaptive behavior and no increase in maladaptive behavior. No relocation syndrome was evidenced as prerelocation preparation appears to have averted the deleterious effects of transfer.


Some correlates of language deterioration in severely and profoundly retarded long-term institutionalized residents.

Progress or deterioration in language use was observed in two samples of retarded institutionalized residents. One sample was observed twice, and the other three times, at 5-year intervals. We coded change in language use as noncommunicating, regressed irregular, stable, or progressed. Change in language use was found to be related to two indicators of intellectual capacity. Central nervous system involvement may play a part in irregular or totally absent communication. Institutional policies regarding transfer of residents also affect the apparent language deficit in longer-term residents.


Age, intelligence, and inspection time.

Ten young males whose IQ scores ranged from 51 to 71 were compared on a simple discrimination task with 10 male university students of the same CA and 28 nonrelated male children. Estimates of inspection time (lambda) were obtained from the pattern of errors made by each subject; lambda is assumed to reflect the rate at which sensory input is accumulated and processed. Average estimates of lambda from four groups of children (7, 8, 9, and 10 years) were 147, 142, 137, and 139 msec, respectively. The mean for university students was 130 msec, whereas that for retarded adults was 256 msec. Mean reaction time (RT) of all nonretarded groups increased as stimulus-exposure duration decreased, children being slower than adults. Retarded subjects' RT was less influenced by stimulus-exposure duration and was faster than that of nonretarded groups at the shortest exposure. These results suggest that slower perceptual speed among retarded persons is a consequence of a permanent deficiency; differences in response strategy may explain the differences in RT.


Informant scoring errors on the Adaptive Behavior Scale.

Adaptive Behavior Scale Booklets (N = 284) completed by institutional direct-care personnel were examined for scoring errors. An average of over 2 errors per booklet was calculated, with the most prevalent errors involving simple addition or failure to subtract when directed. It was suggested that the format of the Adaptive Behavior Scale fosters errors of underestimation. Possible solutions to this problem were discussed.


Categorizing behavior in terms of severity: considerations for part two of Adaptive Behavior Scale.

Forty-five respondents were asked to rate the items in the Violent and Destructive Behavior domain from Part Two of the AAMD Adaptive Behavior Scale on a 1 (not very severe) to 4 (extremely severe) scale. In addition, they were asked to assign the items to one of five categories based on the effects of the behavior on the environment. There was considerable agreement concerning both the severity and the appropriate category for each item. Suggestions for revision of Part Two, including the need for a weighting system and more precise definitions of the behavior items, were discussed.


Inadequacy of brief IQ measures in the classification of mentally retarded prisoners.

This study was designed to evaluate the use of the Slosson Intelligence Test (SIT) and a Wechsler Adult Intelligence Scale (WAIS) short form in determining the intellectual capacity and educational/treatment needs of mentally retarded offenders. The subjects were 52 male prisoners with borderline or retarded intellectual functioning. Their WAIS full-scale IQs were found  to be significantly different from their WAIS short-form and SIT IQs. These results suggest that we must continue to use the full WAIS in evaluating mentally retarded offenders.


Testosterone levels in female partners of infertile couples. Relationship between androgen levels in the woman, the male factor, and the incidence of pregnancy.

Plasma testosterone levels were measured in the female partners of 146 consecutive infertile couples. The incidence of hyperandrogenism in the woman was correlated with ovarian function, incidence of pregnancy, male factor, and response of plasma testosterone levels to prednisone treatment. Over 70 per cent of the patients had pretreatment testosterone levels above 40 ng. per 100 ml. while after a minimum of two months of therapy approximately 80 per cent had levels below 40 ng. per 100 ml. High levels of plasma testosterone were associated with significant prolongation of the follicular phase of the cycle and increased incidence of amenorrhea or anovulation. An over-all pregnancy rate of 50.4 per cent resulted from the treatment. A direct relationship between pregnancy rates and sperm density as well as between pregnancy rates and degree of suppression of plasma testosterone after therapy was observed. These results demonstrate a high incidence of hyperandrogenism in female partners of infertile couples. The effectiveness of glucocorticoid treatment appears to be related to suppression of excessive androgen levels. The data also suggest that infertility is a relative state related to the fertility potential of each member of the couple. Improvement of the fertility potential of either member may result in conception.


Quantitative bacteriology of the vaginal flora in vaginitis.

Vaginal flora was studied quantitatively in 29 sexually active women, 16 to 33 years of age, to define the role of C. vaginale in vaginitis. Seventeen were asymptomatic and 12 complained of symptoms of vaginitis. Seven asymptomatic women had scant secretions: four of these seven had C. vaginale at log10 6 to 9 CFU per milliliter, none of whom had "clue" cells; none had trichomonas or candida; six had lactobacilli at log10 7 to 9.7 per milliliter; only one had Bacteroidaceae at greater than log10 5 per milliliter. Ten asymptomatic women had easily collectable secretions; eight of 10 had C. vaginale at log10 6.5 to 9.6 per milliliter, three of whom had "clue" cells; four had trichomonas and none candida; nine had Lactobacilli at log10 7 to 9.3 per milliliter; four had Bacteroidaceae at greater than log10 5 per milliliter. Twelve had vaginitis: five of 12 had C. vaginale at log10 7.9 to 11 per milliliter, one of whom had "clue" cells; nine had either trichomonas or candida or both and three had no pathogen, including C. vaginale; 10 had Lactobacilli at log10 7 to 10 per milliliter; six had Bacteriodaceae at greater than log10 5 per milliliter. Three had "clue" cells in absence of C. vaginale.


Use of intramuscular 15(S)-15-methyl prostaglandin F2alpha in failed abortions.

Forty-five of 49 patients were aborted successfully with 15(S)-15-Me-PGF2alpha after previous techniques to induce abortion had met with failure in 39. Nine patients had spontaneous premature rupture of membranes without onset of labor. The majority of patients aborted within 7 hours following initiation of this method of treatment.


Defects of the central nervous system in Finland. IV. Associations with diagnostic x-ray examinations.

Based on the Finnish Register of Congenital Malformations a search was undertaken to find possible associations between defects of the CNS and diagnostic x-ray examinations of the mother during pregnancy as well as pelvic x-ray examinations prior to pregnancy. Time-area--matched pregnancies and polydactylic children were used as controls. The risk of having a microcephalic child was increased for mothers with pelvic x-ray prior to pregnancy, but the number of discordant pairs was small. Of the examinations performed during pregnancy, fetal x-ray was significantly more common among mothers who delivered a CNS-defective child. No associations were observed for other kinds of examinations.


Estimation of fetal weight from ultrasonic measurements.

Ultrasonic measurements were made on 65 fetuses within 48 hours of delivery. Multiple regression analysis of birth weight and the natural logarithm of birth weight against several measured variables were obtained. The formula giving the best correlation was a polynomial regression of the natural logarithm of birth weight vs. trunk circumference, circumference, and a long axis measurement. The correlation was improved by excluding the first 15 patients but was not improved further by excluding the next 15. The best correlation was 0.944, giving a predicted birth weight error of +/- 103 Gm. (1 S.D.).


Genital mycoplasmas and birth weight in offspring of primigravid women.

The relationship between colonization of pregnant women by Ureaplasma and Mycoplasma and the outcome of pregnancy in a study of 104 women is reported. There were eight abortions but no multiple births or stillbirths. Excluding abortions, the mean gestational length was 39.6 weeks and the corrected mean birth weight was 3.28 kilograms. There was no relationship between maternal colonization by genital mycoplasmas and reduction in birth weight of the offspring, but five of the eight women who aborted harbored Ureaplasma, suggesting an increased trend toward abortion in women harboring Ureaplasma.


Differences in localization of insulin receptors and adenylate cyclase in the human placenta.

The interactions of hormones with plasma membranes in the human placenta were characterized for specific fetal and maternal components. The microvillus brush border membrane, which is exposed to maternal blood in the intervillous space, was markedly enriched in specific insulin receptors but contained no hormone-sensitive adenylate cyclase. On the other hand, a basal plasma membrane fraction, which is presumably exposed more directly to fetal hormones, contained adenylate cyclase which was sensitive to prostaglandins, epinephrine, and fluoride but was not enriched in insulin receptors or other brush border markers. This study demonstrates separate fetal and maternal aspects of placental-hormone interactions. This separation and the relative impermeability of the placenta to hormones may allow for independent maternal and fetal components of the interaction of hormones with the placenta.


Intrapartum fetal heart rate and sudden infant death syndrome.

The intrapartum fetal heart rate (FHR) tracings of 20 infants who died of sudden infant death syndrome (SIDS) and 20 matched control infants, both drawn from a population at increased obstetrical risk, were compared. This is a blind retrospective study aimed at quantifying (a) the incidence of FHR patterns, (b) the range of FHR and variability levels, and (c) the episodes of variable and late decelerations occurring in conjunction with abnormal FHR levels. Tracings of SIDS infants were similar to those of control infants. Although the three infants with bradycardic FHR levels were restricted to the SIDS group, infants in this group could not be reliably differentiated from control infants on the basis of intrapartum FHR tracings.


Physiological and behavioral responses to starvation in the golden hamster.

Physiological and behavioral responses of adult hamsters to starvation were studied by measuring food intake, weight recovery, serum concentrations of glucose, insulin, free fatty acids and beta-hydroxybutyrate, and ketonuria in animals subjected to different weight losses, diets, and durations of fast. Hamsters were debilitated by fasts longer than 12 h or leading to greater than 20% weight loss. Hamsters' feeding patterns were unmodified by fasts ranging between 5 and 12 h and showed no circadian periodicity. Hamsters predominantly recovered from weight losses without increasing their food consumption (unless they were offered a diet of pellets and seeds) and without changing their meal patterns, at a rate of weight gain proportional to the magnitude of preceding weight loss if provided with uninterrupted access to food. By 8 h of fast, blood metabolites were indicative of mobilization of body fat. Hamsters are thus behaviorally unresponsive to duration of fast, but compensate physiologically for weight losses with proportional increases in the rate of weight gain.


Influence of somatostatin on glucagon- and epinephrine-stimulated hepatic glucose output in the dog.

Glucose kinetics were measured using [3-3H]glucose in conscious dogs during the infusion of: 1) glucagon alone; 2) glucagon plus somatostatin with insulin replacement; 3) epinephrine alone; and 4) epinephrine plus somatostatin with insulin and glucagon replacement. Infusion of glucagon alone resulted in a 10-15 mg/dl rise in plasma glucose and a transient 45% rise in glucose production. When somatostatin and insulin were added, a four- to fivefold greater rise in plasma glucose and glucose production was observed. Glucagon levels were comparable to those achieved with infusion of glucagon alone, whereas peripheral insulin levels increased three- to fourfold above baseline, suggesting adequate replacement of preinfusion portal insulin levels. Infusion of epinephrine alone produced a 40% rise in plasma glucose and a 100% rise in glucose production. When somatostatin, insulin, and glucagon were added to epinephrine, the rise in glucose production was reduced in 65% despite replacement of glucagon levels and presumably mild portal insulin deficiency. These findings suggest that somatostatin: 1) potentiates the stimulatory effect of physiologic hyperglucagonemia on glucose production independent of insulin availability and 2) blunts the stimulatory effect of physiologic increments of epinephrine independent of glucagon availability.


Calcium and phosphorus deficiency in rats: effects on PTH and 1,25-dihydroxyvitamin D3.

Weanling male Holtzman rats were fed calcium.deficient, phosphorus-deficient, or control diets for 8 wk. Parathyroid hormone (PTH) was measured by radioimmunoassay, and 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) by a competitive binding assay. Rats fed the calcium-deficient diet (0.01% calcium, 0.6% phosphorus) became mildly hypocalcemic after 6 days. Serum calcium levels reached 5.5 +/- 0.4 mg/dl (mean +/- SD) in 5 wk (control 10.3 +/- 0.4 mg/dl). PTH increased from 285 +/- 112 to 3658 +/- 428 pg/ml within 6 wk. Maximum serum levels of 1,25(OH)2D3 (111.8 +/- 17.3 vs. control 11.4 +/- 3.8 ng/dl) were reached at 3 wk and thereafter declined to 44.6 +/- 14.0 ng/dl. In rats fed the phosphorus-deficient diet (0.6% calcium, 0.04% phosphorus), serum phosphorus fell within 24 h from 9.1 +/- 0.6 to 3.2 +/- 0.1 mg/dl, recovered to 5.6 +/- 0.4 mg/dl for 2-3 days, and then declined again. Serum calcium reached a maximum of 14.4 +/- 0.4 mg/dl at day 2 (control 10.8 +/- 0.5 mg/dl) and then slowly declined. PTH decreased within 24 h from 243 +/- 59 to 36 +/- 0 pg/ml in phosphorus-depleted rats. Serum levels of 1,25(OH)2D3 increased within 24 h and remained elevated after 6 wk of phosphorus deprivation (61.2 +/- 11.7 ng/dl vs. control 18.3 +/- 0.4 ng/dl).


Prostaglandins and tetrodotoxin-insensitive relaxation of opossum lower esophageal sphincter.

Field stimulation with pulses of 0.5 or 5 ms relaxed isolated strips of lower esophageal sphincter (LES) of the opossum; only responses to 0.5-ms pulses were inhibited by tetrodotoxin. Black widow spider venom prevented relaxation to both stimuli; thus both stimuli may release nonadrenergic inhibitory mediator. Isoproterenol, but not PGEs or ATP, was a consistent relaxant of LES. PGF2alpha (approximately 1 microgram/ml) and stable endoperoxides (approximately 10 ng/ml) stimulated LES muscle. Doses of indomethacin (IDM) or 5,8,11,14-eicosatetraynoic acid (ETA), which inhibited contractions to arachidonic acid increased then abolished LES tone, inhibited relaxations to 5-ms pulses and less effectively to 0.5-ms pulses. Inhibition of relaxation preceded loss of tone. Tone could be restored by carbachol, PGEs, or PGF2alpha and relaxation after IDM but not ETA was also restored. Prostaglandins may participate in functioning of nonadrenergic inhibitory nerves and in maintaining sphincter tone. Cells that did not appear to be smooth muscle were in gap junction contact with smooth muscles and closely apposed to nerves with small agranular vesicles. A role for these structures, which are postulated to be interstitial cells, in tetrodotoxin-insensitive prostaglandin-related release of nonadrenergic inhibitory mediator was proposed.


Mesenteric lymph proteins in zinc-deficient rats.

Because zinc apparently has a role in amino acid utilization, we have studied possible consequences of zinc deficiency on the metabolism of amino acids in the intestinal mucosa by examining proteins transported via the mesenteric lymph in zinc-deficient and zinc-supplemented rats. Mesenteric lymph ducts were cannulated under pentobarbital, and on recovery the animals were fed [14C]leucine as a pulse dose by duodenal infusion. Protein output via intestinal lymph was generally constant over the infusion range studied. Total lymph protein output was not affected by zinc deficiency or supplementation. The electrophoretic pattern of the lymph protein revealed a protein band that migrated with the alpha2-globulins coincidental to zinc deficiency; the band disappeared after zinc supplementation. There was an inverse zinc-copper relationship in mesenteric lymph; duodenal infusion of zinc to deficient rats was followed by a decrease in lymph copper. Deficiency of zinc seems to have little influence on the quantitative aspect of protein carried in mesenteric lymph but seems to be involved with the nature of the protein in this body fluid.


Augmented vagal release of antral gastrin by 2-deoxyglucose after fundic vagotomy in dogs.

To study the relation between gastrin released by vagal excitation and the secretion of H+ and pepsin under various conditions, central vagal excitation was induced by 2-deoxyglucose (2DG) in doses of 50, 100, and 200 mg/kg body wt given as a single intravenous injection in seven gastric fistula dogs, three with fundic vagotomy and four with intact vagi. Serum gastrin increased linearly with dose doubling in both groups but was twice as high in the vagotomized dogs. Total acid output for 3 h was related linearly to integrated gastrin output in both groups, but the slope, H+/gastrin, was 10 times steeper in the vagally intact dogs (330 vs. 34 mueq/pg gastrin-ml-30 min) and pepsin output almost 20 times greater [5,400 peptic units (PU) vs. 296 PU]. Acidification of the antrum to pH 1.2-1.4 eliminated the gastrin response to 2DG in both groups of dogs. Atropine (100 microgram/kg iv) reduced serum gastrin in the vagotomized and increased it in the intact dogs. Atropinization uncovers stimulation by 2DG by pathways that do not involve muscarinic cholinergic receptors. Stimulation by both pathways is suppressible by acid. We conclude that fundic vagotomy removes an inhibitor of vagal gastrin release.


Hepatic extraction of bile salts in conscious dogs.

The enterohepatic circulation of cholic acid conjugates (CAC) was studied in three conscious dogs by comparing the relationship of the concentration of CAC in portal, hepatic, and peripheral venous plasma samples collected simultaneously. The pool of CAC in each dog was labeled with 14C. Catheters were surgically placed in the jugular, left hepatic, and portal veins. Each dog was studied on 2 consecutive days, and each study consisted of a series of samples withdrawn from each catheter at 15-min intervals before and after gallbladder contraction with cholecystokinin. The concentration of CAC in the portal vein ranged from 3 micron (fasting) to 235 micron (after gallbladder contraction). In individual studies, the concentration of CAC increased four to sixfold. A linear relationship exists between the concentration of CAC in the portal vein to that in the hepatic and jugular veins. Thus, the fractional hepatic extraction of CAC is constant over the physiological range of the concentration of CAC in portal venous plasma. Mean extraction varied among the six studies from 0.618 +/- 0.072 (+/- 1 SD) to 0.983 +/- 0.010.


Effect of solute-coupled volume absorption on oxygen consumption in cat ileum.

The effects of solute-coupled volume absorption on blood flow, oxygen consumption, and vascular resistance were analyzed in autoperfused segments of cat ileum. Intestinal absorption was stimulated by placing either Tyrode solution, Tyrode + glucose, or Tyrode + taurocholate into the ileal lumen. Net volume absorption rates (Jv,m) were determined using a volume recovery method. Oxygen consumption (VO2) increased during the absorption of all solutions. The absorption of Tyrode solution plus glucose caused the greatest increase in VO2, whereas Tyrode plus taurocholate resulted in the smallest increase. For Tyrode solution and Tyrode plus glucose absorption, the increased VO2 was due predominantly to an increased blood flow, whereas the increased VO2 with taurocholate resulted from an increased oxygen extraction. A linear relationship between the change in VO2 during transport and Jv,m was aquired for Tyrode solution, and Tyrode + glucose. The results indicate that the oxygen requirements of the absorbing intestine are dependent on both the rate of transport and the solutes being transported.


Local intrarenal vasoconstrictor-vasodilator interactions in mild partial ureteral obstruction.

Micropuncture studies were performed in Munich-Wistar rats with surgically created chronic partial unilateral ureteral obstruction (UUO). Mean values for superficial single nephron (SN)GFR, total GFR, and initial glomerular plasma flow rate (QA) in obstructed kidneys were essentially identical to values in nonobstructed kidneys. Nevertheless, glomerular capillary hydraulic pressure (PGC) was significantly higher in obstructed than in nonobstructed kidneys. This increase in PGC served to offset the markedly reduced glomerular capillary ultrafiltration coefficient that was also confined to the kidneys ipsilateral to the ureteral obstruction. During infusion of indomethacin or meclofenamate, SNGFR and QA decreased significantly, in association with elevations in arteriolar resistances in obstructed kidneys, whereas such changes were not observed in nonobstructed kidneys. The results suggest that local intrarenal factors, rather than circulating or systemic factor(s), bring about functional adaptations to partial ureteral obstruction. In particular, an indomethacin- and meclofenamate-sensitive vasodilator (presumably prostaglandin) plays a role in antagonizing the effects of a simultaneously acting vasoconstrictor which, although not identified, displayed the functional properties of angiotensin II.


Fluoride tissue distribution: short-term kinetics.

The short-term distribution kinetics of 18F, with and without added carrier, were studied in 12 soft tissues and femur following intravenous administration in rats. The animals were killed in groups of four at 5, 10, 15, 20, 30, and 60 min after the dose. A tissue was judged to be kinetically homogeneous with plasma if an early and constant tissue water-to-plasma (T/P) 18F concentration ratio was established. In the carrier-free study, liver, heart, skin, fat, and kidney met this criterion. In the presence of carrier, four other tissues were added to this group. Brain, resting skeletal muscle, spleen, and femur did not achieve constant T/P values. The addition of carrier resulted in significantly lower T/P ratios in nine tissues. This was especially marked in femur. It is concluded that 1) none of the soft tissues studied strongly binds 18F; 2) most of these tissues are kinetically homogeneous with plasma; and 3) the presence of carrier fluoride can significantly influence the kinetic behavior and distribution of 18F. Finally, based on the current and previously reported 18F T/P ratios, and on reported intracellular-extracellular pH gradients, it is hypothesized that fluoride distribution in several soft tissues is determined by the diffusion equilibrium of HF, that is, by the magnitude of the transmembrane pH gradient.


Active amino acid absorption by proximal convoluted and proximal straight tubules.

Transport of glycine and alpha-aminoisobutyric acid (AIB) was studied in proximal convoluted (PCT) and proximal straight (PST) tubules isolated from rabbit kidney. In both segments, unidirectional lumen-to-bath fluxes (J1 leads to b) (pmol min-1mm-1) of glycine and AIB exceeded corresponding bath-to-lumen fluxes (Jb leads to 1), which demonstrated that both were actively absorbed. During J1 leads to b measurements, intracellular concentrations of both amino acids were greater than the luminal concentration, indicating that the site of active transport was the luminal membrane. Replacement of Na+ by choline in both perfusate and bath (PCT) or perfusate alone (PST) reduced J1 leads to b for glycine to equal Jb leads to 1. Nonlinear fitting of the relationship between J1 leads to b and the mean luminal glycine concentration according to Michaelis-Menten kinetics gave Jmax values of 28.5 (PCT) and 2.5 (PST) pmol min-1 mm-1, and Km values of 11.8 (PCT) and 0.7 (PST) mM. There was a parallel, Na+-independent, nonsaturable component of J1 leads to b characterized by an apparent permeability coefficient of 0.19 micron/s in the PCT and 0.04 micron/s in the PST.


Flow dependence of nonelectrolyte absorption in the nephron.

The axial flow dependence of nonelectrolyte absorption was examined in terms of a model incorporating interactions between net volume absorption and both saturable and nonsaturable solute absorption. The model solutions demonstrated that changes in transepithelial solute transport are produced by changes in the average luminal solute concentration. Even passive non-saturable solute absorption was shown to exhibit dependence on the perfusion rate, and, therefore, on the solute delivery rate, which could be incorrectly interpreted as demonstrating the presence of a saturable absorptive mechanism. For a unidirectional lumen-to-bath solute flux mediated in part by a saturable mechanism, the observed flux is dependent on the permeability of any parallel nonsaturable permeation pathway. This permeability also sets a lower bound on the luminal solute concentration which may be achieved during active net solute absorption by determining the rate of passive solute backleak. Extension of the model to incorporate dependence of net volume absorption on the delivery of nonelectrolytes predicted a relationship between perfusion rate and net volume absorption equivalent to approximately one-third of complete glomerulotubular balance.


Luminal influences on potassium secretion: sodium concentration and fluid flow rate.

Two methods of in vivo continuous microperfusion were used to evaluate separately luminal sodium concentration and fluid flow rate as factors regulating potassium secretion by the renal distal tubule of the rat. Emphasis was placed on evaluating changes in sodium concentration (43-97 mM) and flow rate (4-27 nl/min) within the physiological range. Absolute rates of Na, K, Cl, and H2O transport were measured. Results showed that increasing early distal flow rate without increasing early distal Na concentration significantly increased the absolute rate of potassium secretion by the distal tubule. In contrast, increasing early distal Na concentration, distal Na delivery, and distal Na absorption did not affect potassium secretion if flow rate was not changed. Further studies showed that reducing early distal Na concentration below the physiological range (to 15 mM) caused the direction of net sodium transport to be reversed but did not significantly reduce potassium secretion. Increasing early distal K concentration (to 34 mM) caused the direction of net potassium transport to be reversed. The rate of potassium secretion appears to depend in part on the luminal potassium concentration. Increases in luminal flow rate may increase the rate of potassium secretion by lowering the luminal K concentration.


Measurement of oxygen consumption in voltage-clamped epithelia.

Standard apparatus for in vitro study of anuran epithelia was adapted for the incorporation of Clark oxygen electrodes, permitting the concurrent measurement of electrical current (active sodium transport) and oxygen consumption under voltage-clamp conditions, with independent manipulation of the two bathing solutions. Stability was enhanced by electrical isolation of the O2 electrodes, sensitive temperature control (+/- 0.03 degrees C), and constancy of stirring rate. Mean rate of drift was less than 3.7% of the average rate of basal (i.e., nontransport related) O2 consumption. In the present configuration the response time was less than 15 s. Visual fitting of slopes of O2 tension evaluated rates of O2 consumption with adequate accuracy in the physiological range (basal rates averaged about 20 pmol-s-1-cm-2 toad bladder, corresponding to about 10 pmol-s-1-mg-1 dry wt, or about 5 pmol-s-1-ml-1 chamber volume). Rpresentative slopes were read with a standard deviation of 3.5%.


Hypophysectomy and saralasin on mesenteric vasoconstrictor response to vasopressin.

The dose-response relationship of the mesenteric resistance vessels to vasopressin was studied in anesthetized laparotomized cats before and after hypophysectomy and again during the plateau phase of the response to a prolonged infusion of [Sar1-Ala8] angiotensin II (saralasin), a competitive antagonist of angiotensin II. Hypophysectomy and saralasin each caused an increase in superior mesenteric arterial conductance. Before hypophysectomy infusion of 0.5 mU/(min.kg) of vasopressin caused mesenteric conductance to decrease from 0.168 to 0.156 ml/(min.kg.mmHg), a change of only 0.012 units. After hypophysectomy, the same dose reduced conductance from 0.227 to 0.179 mU/(min.kg.mmHg), a change of 0.048 units. During the plateau phase of the response to saralasin, 0.5 mU/(min.kg) of vasopressin reduced conductance from 0.281 to 0.201 ml/(min.kg.mmHg), a change of 0.079 units. Hypophysectomy and saralasin had little effect on the mesenteric vasoconstrictor response to high doses of vasopressin (2.0-10 mU/(min.kg). The ineffectiveness of low doses of vasopressin on the mesenteric resistance vessels of the intact anesthetized, surgically stressed animal may be due in part to the already constricted state of the bed caused by endogenous vasopressin and angiotensin and in part due to an opposing vasodilator influence, the reflex withdrawal of the vasoconstrictor effect of endogenous vasopressin.


Whole body response of the peripheral circulation following hemorrhage in the rat.

Changes in mean circulatory filling pressure (MCFP) after hemorrhage reflect the whole-body response of the peripheral circulation to restore the driving force for venous return. In this study, changes in MCFP were measured for 15 min following a rapid 8 ml/kg hemorrhage. Three groups of rats were studied: 1) conscious, untreated; 2) conscious, ganglion blocked; and 3) pentobarbital anesthetized. In all three groups, hemorrhage decreased MCFP approximately 2.6 mmHg immediately after hemorrhage. In the conscious untreated rat, MCFP recovered 1.3 mmHg in 15 min; 83% of this recovery was complete within 2 min, and over 50% was complete by 30 s posthemorrhage. With ganglionic blockade, recovery was slowed to about 70% of that in the conscious, untreated animal during the first 5 min after hemorrhage. MCFP recovery was substantially depressed by pentobarbital, averaging only 42% of that in the untreated animal 5 min after hemorrhage. The results demonstrate that peripheral changes can quickly restore nearly 50% of the MCFP decrease occurring immediately after mild hemorrhage and that about one-third of this response is mediated by the sympathetic nervous system. Pentobarbital anesthesia greatly inhibits recovery, although its repressive mechanism is not known.


Distribution of cardiac output during induced isometric exercise in dogs.

Studies were designed to characterize the distribution of cardiac output during induced isometric exercise in anesthetized dogs. The response to isometric exercise involved significant increases in heart rate (+12 +/- 3%(SE)), mean arterial pressure (+13 +/- 2%), cardiac output (+26 +/- 8%), and respiratory minute volume (+75 +/- 26%); total peripheral resistance did not change significantly. Significant changes in blood flow were observed during isometric exercise in kidneys (-18 +/- 6%) and contracting limb muscles (+453 +/- 154%). Flow to liver (hepatic artery), spleen, brain, and myocardium remained near control values. Section of spinal dorsal roots L6-L7 abolished the responses to isometric exercise except for the increase in flow to exercising limb muscles. Alpha-adrenergic receptor blockade abolished the decrease in renal blood flow during isometric exercise; however, the increase in flow to exercising limb muscles was not affected by either alpha- or beta-adrenergic blockade.


Hemodynamic and metabolic adjustments during exercise and shock avoidance in dogs.

The purpose of this study was to examine whether the hemodynamic and metabolic  consequences of a physical (treadmill excercise) and behavioral (signaled shock-avoidance) stressor could be differentiated. To do this, direct continuous recordings of cardiac output, systolic and diastolic blood pressure, and discrete determinations of the arterial-mixed venous oxygen ((a-v)O2) content difference were analyzed in six dogs during exposure to three grades of treadmill exercise and when working on a shock-avoidance task. The results indicated that in five animals the relationship between cardiac output and the (a-v)O2 difference during shock-avoidance conditioning was significantly different from the corresponding pattern observed during exercise. In four animals the data suggested that avoidance conditioning, relative to exercise stress, elicited overperfusion. Behavioral stress also produced reliable elevations in diastolic and systolic blood pressure. These results suggest that, when compared to physical stress, behavioral stress can produce a dissociation of cardiovascular and metabolic processes in the presence of acute pressor responses.


Regional oxygen consumption and supply in the dog heart: effect of atrial pacing.

The effects of atrial pacing on the relationship of O2 supply to demand were studied on a regional basis in the dog heart. Experiments were conducted on fourteen hearts, seven in control pentobarbital-anesthetized, open-chest dogs and seven in dogs paced at 225 beats/min. Regional O2 extraction was determined by a microspectrophotometric method, and coronary blood flow was measured with radioactive microspheres. There was an 89% increase in coronary blood flow, a small but significant decrease in O2 extraction, and an increase in O2 consumption with atrial pacing. With pacing the increase in blood flow and the decrease in O2 extraction were uniform throughout the heart. In control hearts, right ventricular blood flow and O2 consumption were lower than the mean in the septal or left ventricular free wall. In the left ventricular free wall in control, the subepicardial region had a lower O2 consumption and O2 extraction than the subendocardial region. These differences were also preserved during pacing. Due to the large increase in coronary blood flow, the relationship of oxygen supply to demand was improved by atrial pacing.


Myocardial energetics during isometric twitch contractions of cat papillary muscle.

During myocardial tetanus, when activation is maximum and constant, there is a linear relationship throughout contraction between oxygen consumption (MVo2) and the cumulative product of active tension and time (integral of AT). The goal of this study was to determine the relation of MVo2 to integral of AT during isometric myocardial twitch contractions. Ten right ventricular cat papillary muscles were studied in a flow respirometer. MVo2 was determined during contractions unloaded from Lmax to a slack length at successive 100-ms intervals after stimulation. In contrast to the linear relationship observed during tetanus, MVo2/integral of AT varied during twitch contractions: when the muscles were made slack 100 ms after stimulation MVo2/integral of AT was 389 +/- 51 (SE) (nl of O2/mg of dry muscle)/(N of active tension/mm2.s of active tension). This value was 94 +/- 7 at peak active tension and was constant thereafter. There was a continuous increase in cumulative MVo2 as integral of AT increased; before integral of AT began, MVo2 was 0.41 +/- 0.04 (nl of O2/mg)/contraction at Lmax and 0.22 +/- 0.04 at a slack length; at peak isometric tension MVo2 was 1.84 +/- 0.19; for a complete contraction MVo2 was 2.89 +/- 0.25. These data support two concepts 1) activation energy is small and dependent on initial length and tension; and 2) integral of AT is variably energy dependent throughout the entire isometric twitch contraction.


Effects of hemodynamic alterations on wall motion in the canine right ventricle.

Regional right ventricular (RV) wall motion was analyzed in six closed-chest, anesthetized, paced dogs by measuring distances between chronically implanted radiopaque markers on RV free wall and septum. Normally, contraction started in the sinus region 25 ms before conus region. Highest velocities of shortening occurred in the conus region (2.42 +/- 0.33 lengths/s) and in septum-to-free-wall direction (2.56 +/- 0.40 l/s). Percent shortening for all regions was between 12% and 17%. The data indicate that the RV ejects blood by a uniform reduction in its free wall surface area and septal-to-free-wall distance. Reduced venous return decreased end-diastolic length, percent shortening, maximum velocity of shortening, and time to end-systolic length. RV pressure overload increased end-diastolic length and decreased percent shortening and maximum velocity of shortening. LV pressure overload led to a nonhomogeneous contraction pattern. Percent shortening and maximum velocity of shortening increased in sinal and conal transverse directions and decreased in sinal and conal longitudinal directions; these changes indicate a mechanical interaction between RV and LV.


Measurement of endogenous norepinephrine overflow from canine saphenous veins.

A method for the measurement of norepinephrine (NE) overflow from isolated superfused canine saphenous veins is described. This method involves concentrating NE present in the superfusate, followed by measurement of its concentration by high-performance liquid chromatography with electrochemical detection. The limit of sensitivity of the method (defined as a signal-to-noise ratio of 5) was 25 pg. NE concentration measured by this method correlated well (r = 0.95) with that measured by standard fluorometric methods. Electrical stimulation caused an initial overflow of a mean of 115 X 10(-18) mol NE/mg of vein per pulse; this was associated with an increase in isometric tension. With continued stimulation, less NE overflowed into the superfusate, although tension was not reduced appreciably.


Inferior cardiac nerve activity in the cat during occlusion of the mesenteric artery.

A number of studies in this and other laboratories using hemodynamic and pharmacologic evidence have suggested that occlusion of the mesenteric artery evokes a pressor reflex initiated by mesenteric baroreceptors. To provide additional evidence in support of this hypothesis, neurophysiological recordings were made of inferior cardiac nerve activity during mesenteric artery occlusion (MAO). The results indicate that MAO enhances inferior cardiac nerve activity in the cat, providing that the carotid sinus nerves have been cut. Cutting of the mesenteric nerves further facilitates cardiac nerve activity and abolishes the response to mesenteric artery occlusion. The evidence suggests that MAO evokes a reflex sympathetic discharge which is subject to override by the carotid sinus depressor reflex. The afferent limb of the reflex is characterized by a tonic depressor outflow from the mesenteric pressure receptors.


Diminished contractile response of aortas from diabetic rabbits.

We investigated the responsiveness of isolated diabetic and normal rabbit aortic strips to norepinephrine. Alloxan, 160 mg/kg, was administered intravenously 1 mo before experiments were performed. Helically cut thoracic aortic strips from diabetic and control animals were suspended side by side in the same muscle bath. The maximum contractile response to norepinephrine of diabetic strips was 68 +/- 5% of control in eight pairs of animals (P less than 0.001). This differential response was not changed by propranolol or cocaine, indicating that it is not explained by either enhanced beta receptor activity or more avid uptake of norepinephrine by nerve endings. Tyramine responses displayed the same differential, suggesting that endogenous release of norepinephrine also results in a lower response of diabetic aortic strips. Maximum responses to KCl were also markedly depressed in strips from nine diabetic rabbits (P less than 0.005). This indicates that the diabetes-induced changes occur at a stage in contraction beyond alpha-receptor activation.


Hypertension in dogs during antidiuretic hormone and hypotonic saline infusion.

Experimental hypertension was produced in 7 dogs by continuously infusing suppressor amounts of antidiuretic hormone (ADH) and hypotonic saline after renal mass had been surgically reduced to 30% of normal. Data were collected during 9 days of control measurements, 14 days of ADH and saline infusion, and then 3 days of saline infusion to 1) determine the chronic effects of ADH on arterial pressure and 2) determine whether hypertension could be maintained during hyponatremia. During the period of ADH infusion, arterial pressure increased to hypertensive levels while plasma sodium concentration decreased almost 20 meq/1. Also, during the ADH infusion period, the dogs demonstrated decreases in heart rate, plasm potassium concentration, plasma renin activity, and plasma aldosterone concentration. Fluid volume expansion was evidenced by sustained increases in blood volume and sodium space. We conclude that when renal function is compromised, subpressor amounts of ADH can contribute to the development of hypertension, probably due to its fluid-retaining properties and in spite of the attendant hyponatremia.


Regional diastolic mechanics of the left ventricle in the conscious dog.

In eight chronically instrumented conscious dogs, apical and middle left ventricular transverse diameters were measured with pulse-transit ultrasonic dimension transducers. Intracavitary apical and midventricular pressures and intrapleural pressure were measured with micromanometers. Both diameters were normalized as a percent extension from the dimension at zero transmural pressure, determined during a transient vena caval occlusion. During the rapid phase of diastolic filling, there was a 2--5 mmHg pressure gradient from the midventricle to the apex. During late rapid filling, the apical transmural pressure and diameter increased more rapidly and reached diastasis 17 +/- 4 ms earlier than the corresponding midventricular measurements (P less than 0.01). The static diastolic pressure-dimension characteristics at the apical and midventricular levels were not significantly different (P greater than 0.30). The dynamic diastolic pressure-dimension relationship was also similar at the two levels and could be represented by a model incorporating parallel viscous properties. Because of regional differences in pressures and dimensions, however, the dynamic relationship could not be modeled when pressure was compared to the dimension at a different level. Thus, diastolic pressures should be measured at the same level as dimensions when assessing left ventricular diastolic mechanics.


Indices of myocardial oxygen consumption for isotonic contraction.

To investigate the model-independent mechanical determinants of energy expenditure, a respirometer was constructed to study isolated feline papillary muscles. Mechanical parameters recorded were the distance of shortening (deltaL), peak velocity of shortening (Vp), mean velocity of shortening (V), tension-time index (TTI), afterload (P), and the integral of the contraction portion of the phase plane trajectory of velocity and length (integral of VdL). Oxygen consumption (Vo2) during 15-min isotonic contraction periods was monitored with a polarographic electrode. Vp, V, and delta L were inversely related to Vo2 in a curvilinear manner. P and TTI were directly related to Vo2 in a curvilinear fashion. Integral of VdL was inversely related to Vo2 in a linear manner. In several experiments the contractile state of the muscles was augmented by addition of norepinephrine (7 X 10(-8) M).  The relationship between integral of VdL and Vo2 was shifted above and parallel to that for the control muscles. These experiments indicate that the index integral of VdL is linearly related to the oxygen consumed in isotonic contraction of isolated mammalian ventricular myocardium at a given level of contractile state.


Changes in ultrasonic attenuation indicative of early myocardial ischemic injury.

This study was designed to determine whether quantitative alterations in ultrasonic attenuation are associated with myocardial changes occurring after acute ischemic injury. Five hundred seventeen regions of myocardium from 41 dogs were studied in vitro at five intervals after coronary occlusion: 15 min, 1 h, 6 h, 24 h, 3 days, and 6 wk. Quantitative indices of ultrasonic attenuation were determined from the measured frequency dependence of the ultrasonic attenuation coefficient characterizing each myocardial region over the range 2-10 MHz. Independent definition of regions of ischemic injury was provided by either creatine kinase depletion or colloidal carbon dye distribution. Results of this study indicate that ischemic myocardial regions investigated 15 min to 24 h after coronary occlusion demonstrated ultrasonic attenuation significantly decreased from nonischemic regions (P less than 0.05). In contrast, ultrasonic attenuation was significantly increased in zones of ischemia or infarction investigated at 3 days and 6 wk after coronary occlusion (P less than 0.05 and P less than 0.01, respectively). These results indicate that altered attenuation of transmitted ultrasound by myocardium in vitro is an early manifestation of ischemia.


Thermal quantification of region myocardial perfusion and heat generation.

A technique for experimental determination of regional myocardial blood flow and heat generation has been developed, based on a heat-clearance method. This method allows repetitive and frequent measurements of regional blood flow without necessity for biopsy or microspheres. Testing was performed on a pedicle preparation, an intact segment of left ventricular myocardium dependent on a single diagonal coronary artery and situated in situ in the left ventricular free wall. Total blood flow to the pedicle was measured by an electromagnetic flow probe. A specially designed 3-thermistor microprobe was positioned in the pedicle to continuously sense temperature changes in the subepicardium, midmyocardium, and subendocardium. The theory underlying this method is based on a heat balance that includes local myocardial heating, conduction, and convection. Comparison of the predicted time- and position-dependent temperature with that measured experimentally allows extraction of the local myocardial blood flow and heating rates. This method allows resolution of differential flows in subendocardial, midmyocardial, and subepicardial myocardium and provides quantification of dynamic flow changes in each layer in response to various stimuli such as ischemia or pressor agents, without in itself causing damage to the myocardial microvasculature. Our data show total flow, based on summation of thermally calculated regional flows, to have correlation coefficients of 0.88 with both the flowmeter and microsphere results. Resting flow values for Nembutal-anaesthetized, open-chest dogs of 0.66 ml/(g . min) compare favorably with values obtained by microsphere studies. Infusion of norepinephrine increased total flow and all layer flows, but the increase in subendocardial flow with norepinephrine was less than the increase of the other layers, perhaps accounting for the vulnerability of this region during catecholamine stress. Local myocardial heating rates in subepicardial, midendocardial, and subendocardial layers are shown to follow the same dependence on local myocardial blood flow in response to anoxic stress or norepinephrine-induced vasodilation. Specifically, local heating rate increases to a factor of 10 at flow below resting level.


Time course of infarct growth toward the endocardium after coronary occlusion.

Transmembrane potentials and ultrastructure of subendocardial Purkinje and ventricular muscle fibers, isolated 1, 3, 5, 6, 14, and 24 h after coronary occlusion were investigated. Action potentials were recorded from progressively fewer layers of muscle cells as the age of the infarct increased. At 14 h little viable muscle remained. The decrease in the number of electrophysiologically viable muscle fibers correlated with structural evidence that the infarct moved with time toward the endocardial surface until only viable Purkinje fibers remained. Purkinje and surviving ventricular muscle fibers demonstrated a progressive decrease in resting potential, action potential amplitude, and Vmax and a progressive increase in action potential duration. Spontaneous diastolic depolarizations were found in Purkinje fibers only in 24-h infarcts and occasionally in cells deep to the endocardial surface, which may have been muscle cells. We hypothesize that during the first 24 h after coronary occlusion arrhythmias originate near the interface of infarcted and ischemic myocardium. As this interface moves toward the endocardium, this site of origin of arrhythmias moves with it until the Purkinje network is reached.


Biocompatibility of standard and silica-free silicone rubber membrane oxygenators.

Spiral coil membrane oxygenators made from either standard silicone rubber or silica-free silicone rubber were compared using three priming techniques. Standard priming, carbon dioxide priming, and denucleation priming were employed with each type of device. Four-hour venovenous membrane oxygenator perfusions were carried out on awake sheep anticoagulated with heparin. Virtually no differences were observed in any parameters measured between standard silicone rubber and filler-free silicone rubber membranes. Significantly greater platelet losses occurred during the first hour of perfusion with standard priming and with carbon dioxide priming than with denucleation priming, using either type of membrane. These experiments demonstrate that denucleation priming reduces platelet losses during extracorporeal membrane oxygenator perfusion, but that the use of filler-free silicone rubber does not improve the biocompatibility of the membrane.


Determination of frequency response from step response: application to fluid-filled catheters.

The performance of a fluid-filled catheter can be described by reporting its undamped natural frequency and damping ratio. These parameters can be measured by subjecting the catheter to sinusoidally varying pressures at a wide variety of frequencies to obtain the frequency response. They can also be computed from the response to a step change in pressure, which is often easier to produce. This paper derives the required equations and includes a graph which permits one to look up the undamped natural frequency after measuring the period and decay rate of the oscillation following a step change in pressure.


A perfused canine right bundle branch-septal model for electrophysiological studies.

As documented in the literature, isolated ventricular muscle preparations perfused with protein-free media become edematous and deteriorate. We hypothesized that the addition of colloid oncotic pressure to the perfusion medium might affect favorably the electrical characteristics and survival of an isolated right bundle branch-septal muscle preparation perfused via the anterior septal artery. Perfusion with protein-free Tyrode solution produced edema formation and a loss of transmembrane potential of Purkinje and muscle cells within 5.9 +/- 0.40 h. Addition of bovine albumin, 4 g/100 ml, to the Tyrode solution or perfusion with horse serum greatly reduced the formation of edema. Furthermore, intact electrical activity continued for more than 9 +/- 0.31 h (P less than 0.001). The preparations showed a greater diastolic potential and action potential amplitude during perfusion than during superfusion with Tyrode solution. 1) a viable, perfused septal muscle preparation was developed for electrophysiological studies, and 2) colloid oncotic pressure in the perfusion medium is essential to preserve the integrity of the capillary circulation and to eliminate edema formation and tissue death.


Coercive persuasion (brainwashing), religious cults, and deprogramming.

Psychiatric interviews and psychological testing were conducted with 50 members of former members of a variety of religious cults who contacted the authors about the issue of deprogramming. The subjects were divided into four groups: cult members who feared deprogramming, those who had returned to the cult after deprogramming, ex-cult members who had left after deprogramming, and those who had left without deprogramming. There were significant differences between these groups on length of time in the cult, perception of and resistance toward the deprogramming experience, status of parental marriage, and who became a deprogrammer. No evidence of insanity or mental illness in the legal sense was found.


Parental criminality and medical histories of delinquent children.

In clinical practice the authors observed that many of the delinquent children of psychiatrically impaired and/or criminal parents had remarkably adverse health histories. To test their clinical impression they systematically compared the medical histories of 20 delinquent children with criminal parents and 85 delinquent children with less obviously maladapted parents. They found a strong association between paternal criminality and serious medical problems in these delinquent children. On the basis of this finding the authors suggest that the behavioral manifestations resulting from such physical illness or neglect, although they appear genetic in nature, may reflect the physical and psychological consequences of parental neglect and/or battering.


Schizophrenic thought disorders: bizarre associations and intermingling.

The authors assessed bizarre verbalizations elicited from 37 schizophrenic and 16 nonschizophrenic patients. Interviews with subjects indicated that much bizarre schizophrenic language results from patients intermingling material from past and current experiences into their verbalizations. This intermingled material comes from many different problem areas rather than one central emotional complex. It does not arise from emotional overresponsiveness, overinvolved thinking, or delusional ideation. Two factors hypothesized as responsible for bizarre schizophrenic language are the schizophrenic's monitoring problems and difficulty maintaining perspective about his own behavior.


Acupuncture treatment of schizophrenia: report on three cases.

The authors conducted a 9-week blind controlled study of the effects of acupuncture on schizophrenic illness in three patients on an inpatient ward of a psychiatric hospital. This paitents were used as their own controls. The authors compared the effects of acupuncture, pseudo-acupuncture (random needling), and no treatment control periods. Two patients who had had florid schizophrenic symptoms responded positively to true acupuncture treatment and negatively to pseudo-acupuncture. The third patient, whose symptoms were primarily affective-depressive, showed no significant response to treatment. The authors explore the mechanisms thought to be involved in the etiology of schizophrenia, focusing on the cortical arousal hypothesis.


Standards affecting mental health care: a review and commentary.

The author describes the increasing focus on regulation and the standards applied to the field of mental health. He discusses four distinct but overlapping types of standards: 1) clinical, 2) practitioner, 3) program and facility, and 4) payment. He emphasizes the increasing influence of legislation and judicial decisions and points out several trends in standard setting affecting mental health care. Psychiatrists and other mental health practitioners are called on to take a larger role in shaping these standards to ensure that the quality of patient care is not compromised.


Paranoia and platelet MAO in normals and nonschizophrenic psychiatric groups.

The authors compared the correlation between platelet monoamine oxidase (MAO) activity and the Paranoia (Pa) scale of the Minnesota Multiphasic Personality Inventory in several groups. The data suggest that there is a positive association between high MAO activity and high scores on the Pa scale but only in samples with psychopathology.


Complex partial and pseudoseizure disorders.

The differentiation of ictal and nonictal seizure disorders is difficult, particularly in patients suffering from partial seizures with complex symptomatology. The authors state that observation of a patient's habitual seizure during EEG recording is the ideal diagnostic tool and describe their method of seizure activation with sphenoidal electrodes and simultaneous audiovisual monitoring. They emphasize the necessity for early, aggressive treatment of both ictal and nonictal seizure disorders, point out risks to the patient if the incorrect diagnosis is made, and urge further cooperation between psychiatrists and neurologists in this borderland area.


Schizophrenic patients and Schneiderian first-rank symptoms.

Differences between schizophrenic patients with Schneiderian first-rank symptoms (FRS) and those without FRS at the time of hospitalization indicated FRS were associated with behavior consistent with feelings of passivity and helplessness. The two groups responded equally well to treatment in a therapeutic community. Findings support the contention that FRS are not pathognomonic or prognostic in schizophrenia.


Patient access to medical records on a psychiatric inpatient unit.

The authors studied the effects of patient access to medical records during hospitalization in a psychiatric unit of a community general hospital. Questionnaires were completed by about 20 staff and 88 patients, and records were compared with those from an earlier period to note any changes in the written record. Patients reported feeling better informed and more involved in their treatment, and staff said that they became more thoughtful about their notes in the chart. The availability of staff seems crucial to this process and facilitates the working alliance.


Response of patients to participation in psychiatry board examinations.

The patient who volunteers to be a subject for Part II of the certifying examination in psychiatry and neurology is an indispensable but surprisingly invisible participant in a highly controversial process. A survey of the attitudes of 78 patients toward this experience revealed that although they experienced a significant degree of stress, the overwhelming majority viewed their participation in strongly positive terms. The patient's loyalty to the host institution and the manner in which the patient is prepared for the experience appear to be the major factors in determining a positive outcome.


Educating staff to manage threatening paranoid patients.

The threatening paranoid patient is one of the most frightening and difficult patients to treat. The author points out the need for all levels of hospital staff to become more adept at recognizing their own feelings, which often keep them from appropriately managing these patients. He summarizes several crucial points in teaching staff to cope successfully, dividing the process into diagnosis, management of one's emotions, and practice of appropriate therapeutic techniques.


The role of ambulatory medical care in hypertension screening.

Data from the 1975-1976 National Ambulatory Medical Care Survey conducted by the National Center for Health Statistics were examined retrospectively to determine the extent to which blood pressure was measured during visits to office-based physicians in the conterminous United States. Blood pressure was more often measured for females (especially black) than for males although males (especially black) in certain age groups had a higher prevalence of hypertension and comprised the higher proportion of undiagnosed hypertensives. Blood pressure measurement increased with age, but was rarely measured for those under 15 years of age. Blood pressure was measured about 79 per cent of the time when hypertension was present but only 30 per cent of the time when hypertension was absent. When diseases shown to be frequently concomitant with hypertension were diagnosed in the absence of hypertension, blood pressure checks ranged from 24 per cent of visits diagnosed neuroses to 66 per cent diagnosed obesity. Blood pressure was measured during about 12 per cent of visits for diseases of the nervous system and sense organs as well as diseases of the skin and subcutaneous tissue; 24 per cent of visits for infective and parasitic diseases, diseases of the respiratory system, and mental disorders. Blood pressure was measured most often when diagnoses were in the categories of diseases of the circulatory system and endocrine, nutritional, and metabolic diseases. Opportunities for blood pressure measurement during routine visits did not appear to be fully utilized, nor did some specialists take frequent blood pressure measurements. (Am. J. Public Health 69:19-24, 1979.)


Blood pressure control in private practice: a case report.

High blood pressure is most commonly treated in the offices of private physicians. We have attempted to evaluate the efficacy of such care through review of all patient charts of a Board Certified, University Medical Center affiliated internist in New York City. Seventeen per cent had elevated (greater than or equal to 160/95) blood pressures or were taking antihypertensive medication at the time of their last visit. A selected group of 206 charts was examined to determine attendance and blood pressure outcome. Over one-half of these patients were lost to follow-up within a year of their initial visit. Of those who persisted in therapy, 55 per cent achieved good blood pressure control. Blood pressure outcomes among medicated patients were not different from those of patients who received no prescription. These results suggest that this conventional pattern of ambulatory medical care, characterized by a high attrition rate and a failure to adequately control blood pressure, may not be suitable to the long-term management of high blood pressure.


Paramedic programs and out-of-hospital cardiac arrest: I. Factors associated with successful resuscitation.

As part of an evaluation of whether the addition of paramedic services can reduce mortality from out-of-hospital cardiac arrest compared to previously existing emergency medical technician (EMT) services, factors associated with successful resuscitation were studied. A surveillance system was established to identify cardiac arrest patients receiving emergency care and to collect pertinent information associated with the resuscitation. Outcomes (death, admission, and discharge) were compared in two areas with different types of prehospital emergency care (basic emergency medical technician services vs. paramedic services). During the period April 1976 through August 1977, 604 patients with out-of-hospital cardiac arrest received emergency resuscitation. Eighty-one per cent of these episodes were attributed to primary heart disease. Considered separately, four factors were found to have a significant association with higher admission and discharge rates :1) paramedic service, 2) rapid time to initiation of cardiopulmonary resuscitation (CPR), 3) rapid time to definitive care, and 4) bystander-initiated CPR. Using multivariate analysis, rapid time to initiation of CPA and rapid time to definitive care were most predictive of admission and discharge. Age was also weakly predictive of discharge. These findings suggest that if reduction in mortality is to be maximized, cardiac arrest patients must have CPR initiated within four minutes and definitive care provided within ten minutes.


Paramedic programs and out-of-hospital cardiac arrest: II. Impact on community mortality.

Out-of-hospital cardiac arrest was studied in suburban King County, Washington in an attempt to determine the impact of paramedic services on community cardiac mortality. A portion of the study area received paramedic services and the remainder received basic emergency medical technician (EMT) services. A surveillance system identified all prehospital cardiac arrest incidents. The etiology and outcome were determined. Deaths due to primary heart disease (ICDA) codes 410-414) were compared to community cardiac mortality figures for the same period of time and in the paramedic and EMT areas. Between April 1, 1976 and August 31, 1977, 1,449 deaths due to primary heart disease occurred (annual rate of 19.2/10,000 in the EMT area and 13.4/10,000 in the paramedic area). For the same period, 487 patients with out-of-hospital cardiac arrest received emergency resuscitation. The annual incidence of out-of-hospital cardiac arrest was similar in the EMT and paramedic areas (5.6 and 6.0/10,000 respectively). Proportionately more lives of persons with cardiac arrest were saved in the paramedic area than in the MET area. During this 17 month period, the reduction in community cardiac mortality was 8.4 per cent in the paramedic area and 1.3 per cent in the EMT area. These findings suggest that paramedic services have a small but measurable effect on community cardiac mortality.


Changing images of professionalism: the case of public health nurses.

A survey of 89 public health nurses in a California county explored factors that might account for the growing support of unions and subsequent militancy among nurses. As predicted, changes in the backgrounds of public health nurses have occurred over time: 1) older nurses are more likely to have graduated from a diploma program and to have parents of lower educational and occupational attainment than younger nurses; 2) older nurses are more likely to view nursing as a calling and less likely to desire representation in collective bargaining by the union or to believe striking professional; 3) older nurses and those from lower social class backgrounds were less likely to belong to the union and less likely to participate in a county-wide strike. Because age and parental background factors are independently related to our indicators of militancy--union membership and participation in a strike--the results are interpreted as a change in nurses' images of professionalism.


Cut flowers: a potential pesticide hazard.

Following reports of ten cases of possible organophosphate pesticide poisoning in florists exposed to pesticide residues on cut flowers, we conducted a prospective random-sample survey to determine residual pesticide levels on flowers imported into the United States via Miami, Florida. A sample of all flowers imported into Miami on three days in January 1977 showed that 18 (17.7 per cent) of 105 lots contained pesticide residue levels greater than 5 ppm, and that three lots had levels greater than 400 ppm. Azodrin (monocrotophos) was the most important contaminant with levels of 7.7--4,750 ppm detected in nine lots. We examined 20 quarantine workers in Miami and 12 commercial florists exposed to contaminated flowers. Occasional nonspecific symptoms compatible with possible organophosphate exposure were noted, but we found no abnormalities in plasma or red blood cell cholinesterase levels. This study documents a previously unrecognized potential source of occupational pesticide exposure and suggests that safety standards should be set for residue levels on cut flowers.


A performance comparison: USMG-FMG attending physicians.

To determine whether patterns of differences in performance exist between United States Medical Graduate and Foreign Medical Graduate attending Physicians, two types of inpatient hospital audits (Payne Process Audit and the Joint Committee on Accreditation of Hospitals' Performance Evaluation Program-P.E.P. Audit) were conducted in 22 Maryland and Pennsylvania non-federal, short-term hospitals. A total of 6,980 medical records were abstracted from eight diagnostic categories for 1,321 attending physicians; 985 of which were USMGs and 331 were FMGs. The results from both audits indicate that while there is evidence of a strong hospital-type of physician interaction for many of the diagnoses, there was no significant overall difference in performance between USMG and FMG attending physicians. The largest and most consistent differences in physician performance were associated with hospital characteristics, not physician characteristics.


The state mental hospital: a local health department's role.

The publicizing of the abysmal conditions in state mental institutions and the problems precipitated by their deinstitutionalization programs, have challenged local health authorities to develop effective roles in ameliorating these difficulties. Long-view State Hospital is a state mental hospital in Cincinnati, Ohio. The Cincinnati Health Department acted as a change agent to deal with the hospital's many chronic problems and the new difficulties precipitated by moving patients into the community for care. The city conducted its own evaluation of the hospital and its deinstitutionalization program and strongly advocated needed improvements. Problems were encountered in implementing this advocacy role, particularly in relation to the local health department's authority regarding this state-funded and operated institution. However, the many city recommendations that were implemented, the increased funding given the hospital and the community mental health centers, the continuing communication between city and state officials, as well as a follow-up evaluation indicated that the Cincinnati Health Department had played a positive role in the change process. (Am. J. Public Health 69:64-67, 1979.)


Physicians' patient referrals to a nurse practitioner in a primary care medical clinic.

A survey of interns and residents in a Primary Care Medical Care Medical Clinic disclosed that these physicians have a very favorable impression of nurse practitioners' potential contributions to health care delivery, yet refer patients to the nurse practitioner to a much lesser degree than would have been expected on the basis of their attitudes.


A comparison of mail, telephone, and home interview strategies for household health surveys.

The method of data collection in household health surveys can be a major determinant of cost and data quality. A survey strategy can comprise mail, telephone, or home interview methods, individually or in combination to follow up non-respondents. The purpose of this study in Montreal was to compare cost and data quality of various strategies. Strategies which began with mail or telephone contact, followed by the two other methods, provided response rates as high as a home interview strategy (all between 80 and 90 per cent), for one-half the cost of home interviews when used as the sole method. The telephone response rate was higher than the mail response rate. Comparing different follow-up approaches to strategies beginning with mail or telephone, it proved less costly, and equally effective, to use home interviewing as a last resort for persistent non-respondents. Validity of response (comparing individual responses with records of a government health insurance data bank) and willingness to answer sensitive questions were greatest in mail strategy.


Side effects of diphtheria-tetanus toxoid in adults.

During a mass diphtheria-tetanus immunization campaign in November 1975, more than 220,000 doses of diphtheria-tetanus toxoid, adult type were administered to adults throughout Alaska. In Anchorage, where more than 87,000 doses were given, a survey was conducted to determine the frequency of side effects. Postcard questionnaires were mailed to 2,000 randomly selected Anchorage residents; 467 questionnaires were returned by the post office as undeliverable, and 697 questionnaires were completed and returned. A follow-up survey was done of a random sample of the 836 non-responders. Of those responding, 57.8 per cent reported at least one reaction to the toxoids. The most frequent side effects were sore arm (42.7 per cent), swelling at the site of injection (34.8 per cent), and itching (24.2 per cent). Serious side effects occurred less frequently-swelling of the arm below the elbow (1.1 per cent) and abscess or infection (0.7 per cent). Of those vaccinated, 0.5 per cent saw a physician. There were no statistically significant differences in reaction rates by age group, except for sore arms. The jet injector produced more arm swelling at the site of injection, hives, and itching. More women than men reported adverse reactions, especially sore arm, swelling at the site of injection, and itching. Fear of adverse side effects should not preclude mass vaccination of adults. (Am. J. Public Health (69:246-249,1979.)


Statistical models of the demand for emergency medical services in an urban area.

First- and second-order statistical regression models are presented for the Emergency Medical Services (EMS) demand in an urban area as it relates to various socioeconomic, demographic, and other characteristics of the area. Individual models are formulated for different types of medical emergencies with the city of Atlanta, GA, serving as the data base. These models are generally shown to provide excellent fits to the empirical data.


Risk factors of lip cancer: a critical evaluation based on epidemiological comparisons.

A description is given of the occurrence of lip, skin, and intraoral cancers in Finland in the period 1953-1973 with the aim of testing certain etiologic hypotheses. In addition, data on lip cancer were correlated with those of some other types of cancer. Substantial differences with respect to various epidemiologic parameters were found between lip and skin cancers. However, there were similarities between lip cancer and cancers of the upper gastrointestinal canal and respiratory organs (especially lung cancer). Negative geographic correlation was found between the age-adjusted incidence rate of lip cancer and that of cancers of the colon and prostate. In addition, the correlation was highly negative for the median income per capita (p less than 0.001). It was concluded that, in terms of cancer etiology, lip cancer is more closely related to cancer of the oral cavity than to that of the skin. Moreover, some specific socioeconomic factors associated with a low standard of living must be considered as noteworthy risk factors of lip cancer.


Characteristics of individuals who identify a regular source of medical care.

Having a source where medical services are regularly received is an antecedent to securing high quality medical care; it facilitates access and indicates that the individual is not alienated from the health care delivery system. In this paper we develop models to characterize individuals, both children and adults, who claim a regular source of care. The models are estimated using a logit analysis (since the dependent variable is 0-1) applied to survey data on residents of East Palo Alto, California. These data indicate that in this low-income, predominately black population the most important factor influencing whether a child will have a regular source of medical care is whether the parents have a regular source. For adults, the anticipated need for care (as measured by health status), time in community, and sex were all found to be important. The type of individual least likely to have a regular source of care is a low-income, unmarried male who is in good health and is a recent arrival to the community. The individuals most likely to need easy access to medical care and continuity of care are most likely to have a regular source of care, and vice versa.


Feasibility of the randomized response technique in rural Ethiopia.

A multiple answer model of Randomized Response Technique (known as Hopkins RRT Model II) was tried in a rural area (Nekempte) in Ethiopia to estimate the incidence of induced abortion among currently married women of childbearing age. In the RRT adopted here, the question on abortion--sensitive as it is--was preceded by two innocuous "practice questions". Despite the very low literacy level of the women, nearly all of them cooperated. The RRT estimates in regard to the two innocuous "practice questions" were fairly reasonable, while the RRT estimate of the rate of induced abortion (35 per cent) was far higher than that derived from direct reporting. The differentials in abortion rates by age and parity were consistent with expectation. A post RRT survey indicated that more than one-half (58 per cent) of the women found RRT "easy" or "moderately easy" to understand, while nearly 80 per cent of them thought that there was no "trick" involved in it.


Implications of rubella susceptibility in young adults.

Rubella history and antibody titre were determined for 457 medical, graduate, and physician assistant students. Eighteen per cent were estimated at risk for rubella. There were no male-female differences. Health-profession students did not differ in rubella immune status from the general population. History was not helpful in assessing immune status. Approximately one-half of persons with low antibody titres had considered themselves immune, while one-half with moderate to high antibody titres had considered themselves at risk. Less than one-half of students with low antibody titres available themselves of immunization which was recommended and offered. With a high percentage of adult females at risk for rubella even in a health-motivated population and with poor follow-up on recommended immunization, current immunization practices must be improved if congenital rubella syndrome is to be further reduced. Mass inoculation of school age males and prepubertal school age females without prior determination of rubella antibody titres is suggested as a cost-effective means of decreasing incidence of congenital rubella syndrome.


The New York rubella incident: a case for changing hospital policy regarding rubella testing and immunization.

A case of rubella in a male obstetrics-gynecology house staff member exposed 170 staff members and 11 prenatal patients to the clinical disease. Of 163 staff members tested within one week of exposure, 132 (80 per cent) were not susceptibles. Repeat titres three weeks later on 28 susceptibles remained negative. Of the 11 patients exposed, three were susceptible and none seroconverted.


Surgical treatment of partial Achilles tendon rupture.

Fifty-four patients with a total of 58 partial ruptures of the Achilles tendon were treated surgically. The postoperative observation time ranged from 8 months to 7 years. Forty-six patients indicated that they were pleased with the results, 8 were satisfied, and 3 were unsatisfied (one died during the interim). Thirty-seven of the 44 patients who had been engaged in competitive sports preoperatively were able to return successfully to the activity. We recommend surgical treatment if conservative treatment for presumed tendinitis is not successful. The operative procedure may encourage revascularization to the Achilles tendon and innervation after surgical excision of the pathologic and degenerated tissue.


Conditioning program for competitive figure skating.

To test the feasibility that traditional interval training methods could be adapted to the needs of competitive figure skaters, an interval skating program was conducted during a 3-month period for a group of skaters at diverse levels of proficiency. The program required only a small portion of the total ice time utilized by the skaters on a daily basis, i.e., 1/2 hr, three times a week. On alternate days, the skaters used the same amount of time in a strength training program. A flexibility-stretching facet was to be done by the skaters on a daily basis. Progress was evaluated by treadmill oxygen consumption determinations and ability to perform a 1/2-mile skate effort. Over the course of the 3-month period, the skaters in the program showed an average increase in oxygen consumption of 9% from 44.73 cc per kg per min to 55.51 cc per kg per min. This was accompanied by an average 10-sec reduction in the timed effort at the 1/2-mile skate. Subjectively, the skaters were less fatigued during their freestyle skating programs and were able to improve consistency at skilled maneuvers in the last minute of their performances. This initial effort to evaluate the efficacy of this type of a training program for competitive figure skating seems to have proven to be beneficial to the skaters. Currently, we are continuing our efforts to expand the program.


Anterior cruciate ligament: functional anatomy of its bundles in rotatory instabilities.

The functional anatomy of tha anterior cruciate ligament was studied in 18 freshly amputated specimens. The cruciates were observed in the extremes of flexion and extension, and in midposition in simulated weight-bearing and nonweight-bearing conditions. Five femoral shafts were split longitudinally so that the femoral and tibial attachments of the ligament could be inspected. The findings indicated that (1) the anterior cruciate ligament is a secondary static stabilizer against rotatory instabilities of the knee; (2) the anteromedial bundle contributes to anterolateral stability; (3) the intermediate bundle adds to straight and anteromedial stability; and (4) the posterolateral bundle assists in posterolateral stability. Specific bundles and functions of bundles must be considered in reconstruction, substitution, or replacement of the anterior cruciate ligament.


Cylinder or mobile cast brace after knee ligament surgery. A clinical analysis and morphologic and enzymatic studies of changes in the quadriceps muscle.

Sixteen patients participated in a prospective randomized trial in which a standard cylinder cast was compared with a mobile cast brace. Both were worn for 4 weeks, beginning at 1 week after reconstruction of the anterior cruciate ligament. The athletes that had used a cast brace could return to sports activities in about one-half the time it took for the athletes with a standard cast. The patients with a standard cast showed a significant atrophy of Type I (slow twitch) muscle fibers in the vastus lateralis. The cast brace patients did not show any significant changes in cross-sectional areas of Type I or Type II (fast twitch) muscle fibers. The standard cast patients had a significant reduction of succinate dehydrogenase (SDH) activity in the vastus lateralis whereas the patients with the cast brace did not show any significant changes. No difference in surgical end result was found. A cast brace with a limited range of motion between 20 and 60 degrees of flexion is recommended as the standard postoperative treatment after knee ligament surgery.


Extra-articular reconstructive surgery for combined anterolateral-anteromedial rotatory instability.

The knees of 14 patients (12 male and 2 female) were treated surgically by extra-articular reconstruction for combined anterolateral-anteromedial rotatory instability. Healing and rehabilitation required approximately 8 months after the operations. Only after adequate rehabilitation, including return of full confidence, were the patients released to full activity (although contact sports are not recommended). Of the group, 12 patients returned for follow-up evaluations and one returned a questionnaire. One patient was lost to follow-up. One patient did not return to full activity because in the 3rd month postoperatively, he stepped in a hole while jogging, reinjured his knee, and refused further surgery. The functional improvement in this series by our extra-articular procedure (a combination of an anteromedial capsulorrhaphy and pes transfer medially with Ellison's modification of an iliotibial band rerouting and partial biceps advancement laterally) compares favorably with the reported anterior cruciate ligament reconstructions. Further comparisons with longer periods of time after surgical procedures are needed to determine whether extra-articular repair with interarticular reconstruction of the anterior cruciate ligament is significantly better than this technically easier extra-articular repair alone.


Chondromalacia patellae in athletes. Clinical presentation and conservative management.

A comprehensive conservative management program for chondromalacia patella in athletes has been presented. The clinical manifestations and the efficacy of conservative treatment have been documented in the prospective study of 100 consecutive athletes. The over-all success rate was 82%, and 18% were considered to be failures of conservative treatment. Only 8 of these 100 athletes have required surgical treatment. It was concluded that this type of conservative management is effective in the majority of athletes with symptomatic patellofemoral syndromes, and that surgical treatment should be necessary for only the relative few who fail to respond to an adequate trial of conservative treatment.


Blockade by vitamin A of the occurrence of permanent vaginal changes in mice treated neonatally with 5alpha-dihydrotestosterone.

Estrogen-independent, persistent proliferation and cornification of the vaginal epithelium occurred in ovariectomized adult mice which had received neonatal injections of 50 microgram 5alpha-dihydrotestosterone (DHT). The occurrence of the permanent vaginal changes was prevented by injections of 200 IU vitamin A acetate (VA) given simultaneously with DHT. In 45% of the DHT plus VA-treated, ovariectomized mice, clear cells with pale cytoplasm appeared in the basal layer of the degenerating epithelium, while they came out in the epithelium of 13% of the ovariectomized mice receiving neonatal injections of DHT alone. For suppressing the permanent vaginal changes, including high mitotic rate, more than 1 month was required after the combined treatment. However, the occurrence of the permanent changes was not blocked by VA given after the DHT treatment. Permanent proliferation and squamous metaplasia took place in the uterine epithelium of the DHT-treated mice. Neonatal injections of VA also prevented the occurrence of the permanent uterine changes when given simultaneously with DHT but not when given after the androgen treatment.


Developmental interactions between the adjacent parts of combined heterologous skeletogenous territories.

The right limb buds of chick embryos (H.-H.stages 22 to 26) were transversely divided at approximately the presumptive zeugopod mid-length, and (1) the distal parts exchanged between wing and hind-limb bud in apdv-reversed orientation (operation A), or (2) the severed distal part of the leg bud was reoriented in situ (operation B). Both the proximal and distal segments of the zeugopodal bones developing from the recombined portions of presumptive heterologous territories showed characteristic differences of size and shape in comparison to the corresponding parts of the skeletal pieces of the zeugopod of the intact, control limbs. These developmental changes are interpreted as being the consequence of reciprocal influences exerted by the adjacent parts of mesenchymal territories (or blastemata) that, under normal developmental conditions, are destined to give rise to different bones. Such influences may enhance or depress the growth potential of the skeletogenous populations affected, and, within each cell population, modify the geometry of the growth processes by which the various parts of each skeletal piece attain their typical shape.


Cortical desmoid-like lesion of the proximal humerus and its occurrence in gymnasts (ringman's shoulder lesion).

Eighteen gymnasts were interviewed and examined radiographically for a cortical irregularity of the proximal humerus simulating malignancy. Fifty percent of the gymnasts had the lesion which is considered to be a benign reactive lesion secondary to excessive forces at the pectoralis major insertion to the proximal humerus. All patients were asymptomatic. The lesion is probably unique to gymnasts, particularly those involved with strength moves.