Prevalence of mental illness among 70-year-olds domiciled in nine Copenhagen suburbs.

The results of a study on the prevalence of mental diseases and abnormalities among a geographically well-defined group of 70-year-olds, all living in nine suburbs of Copenhagen, are submitted and discussed. The total psychiatric morbidity was found to be 15.5%; 6.4% suffered from psychoses, males preponderating, and 7.4% classified as "neuroses + personality disorders", females preponderating. Only 15% of the pschotic group were institutionalised. Of the entire material, 5% were demented, and this included 1.l% patients who were severley demented. There was a definite preponderance of males. Of the population, 2.6% were living in their homes with senile or arteriosclerotic dementia. About 1% of the population were looked after in their homes despite severe dementia of varying geneses. Hidden morbidity, meaning that the proband had neither been institutionalised nor had consulted a doctor for mental illness within the past 5 years, made up of 15% of the psychotic group and 19.2% of the group "neuroses + personality disorders + alcoholisms". The total hidden morbidity constituted 2.6% of the population or 16.5% of the demonstrated psychiatric morbidity. The prevalence findings are on the whole on a level with those reported from other studies, most of which have been concerned with population groups over 65 years of age.


Cardiac arrhythmia and behaviour in autistic children.

The behavior and heart rate of autistic children were simultaneously videorecorded in a standard situation. Normal children of two age-groups were also studied. It was found that the heart rate of the autists was characteristically highly variable and more so than that of normal children of the same age or younger. This variability (arrhythmia) however, was behaviour-dependent in all children-involvement in a task resulting in suppresion of the arrhythmia. It was at a maximum in the autists during the performance of stereotyped behaviours. The functional implications of these behaviour-heart rate associations are discussed.


Sjöbring personality dimensions: norms for some American populations.

An American version of the MNT Inventory (Sjöbring personality dimensions) was administered to three separate groups of American subjects. Normative data on the Sjöbring dimensions, including correlational data between the dimensions, was reported for these groups and compared to published normative data from prior studies in Sweden and in the United Kingdom. For the American groups, the correlations between dimensions were negligible or very small, in accord with Sjöbring theory. There were similar patterns to the scale scores and to the correlational data for the American groups and comparable Swedish groups. The results suggest that the American version of the MNT inventory is a valid tool for obtaining Sjöbring dimension scores on American subjects.


Hospitalization of former outpatients diagnosed as psychotic.

A study was made of 612 psychotic outpatients, followed by means of a national case register from their first referral in 1946 to 1955 up to and including 1973. One hundred and sixty-four cases were not found to be registered as inpatients and so must be counted as lost to a registration system based upon hospital admissions. The loss of cases was estimated at around 5% of the total first admissions. Most of the lost cases were borderline psychotics or manic-depressives.


Scintigraphy with 131I-19-iodocholesterol in adrenal disease.

Adrenal scintigraphy after i.v. injection of 131I-19-iodocholesterol has been performed in 4 patients with primary aldosteronism, 5 with Cushing's syndrome and 1 patient with phaeochromocytoma. In primary aldosteronism a unilaternal adrenocortical adenoma was demonstrated in 2 patients, while the method failed in 1 patient to visualize a tumour that was localized by measurements of aldosterone concentrations in the adrenal veins and by adrenal venography; in 1 patient none of the methods demonstrated a tumour. In Cushing's syndrome, adrenal scinitgraphy indicated bilateral adrenocortical hyperplasia in 1 patient and visualized the tumour in 2 patients with adrenocortical adenoma. In all patients with Cushing's syndrome due to unilateral adrenocortical tumour, the accumulation of radioactivity in the contralateral adrenal was suppressed. However, a delayed and slight accumulation of the isotope in the suppressed gland contralateral to an adrenocortical carcinoma was misinterpreted and led to exploration on the wrong side since the tumour did not concentrate radioactivity at all. The method failed in 1 patient to localize the adrenocortical tissue responsible for the relapse of Cushing's syndrome after bilateral adrenalectomy for hyperplasia. In the patient with phaeochromocytoma, no radioactivity was found on the tumour. It is conculded that adrenal scintigraphy is a safe and valuable method for localization of adrenal tumours and their differentiation from adrenocortical hyperplasia. Some diagnostic pitfalls do, however, exist, as demonstrated in this series of patients.


Bone mass in obese subjects.

The inner and outer diameters of the cortex have been measured in 32 obese subjects in the middle of the second metacarpal bone and in the proximal part of radius. The results, which were compared with an age-matched control group, showed that the obese subjects had, on an average, an 11 percent larger cortical area than the controls (p smaller than 0.05). The increased cortical area was caused by the greater outer diameter of the measured bones. There were no significant differences in inner diameters betwee the groups. The inner diameters increased with age in the same way in both obese and control persons, indicating the the former are not protected against osteoporosis in the form of endosteal resorption.


The acute effect of sodium cellulose phosphate on intestinal absorption and urinary excretion of calcium in man.

Intestinal 47Ca absorption has been determined from blood and stool radioactivity after oral administration of the isotope in nine patients before and during cellulose phosphate treatment. Oral administration of 5 g cellulose phosphate concomitant with 47Ca in 100 mg "carrier" calcium as CaCl2 decreased 47Ca absorption by 80 per cent. Cellulose phosphate, 5 g three times daily, decreased urinary excretion of non-radioactive calcium by 47 percent. Urinary magnesium excretion decreased by 47 percent whereas urinary phosphorus excretion increased by 67%. Calcium and magnesium excretion in urine decrease because cellulose phosphate binds divalent cations within the GI tract. The increased phosphorus excretion is probably due to partial hydrolysis of the substance in the gut.


Serum calcitonin response to induced hypercalcemia.

The rise in serum calcitonin (delta-CT240 min) has been measured during hypercalcemia induced by i.v. infusion of calcium gluconate. This calcium infusion test was used in a prospective screening for medullary carcinoma of the thyroid (MCT) in 4 families with Sipple's syndrome as well as in 3 sporadic cases of MCT. In 16 normal controls delta-CT240 was minus 0.2-+ 0.5 ng/ml (mean plus or minus 2 S.D.). Delta-CT240 was normal in 2 patients with chronic hypocalcemia. In all 14 MCT patients delta-CT240 was markedly higher (min-max 2.2-630 ng/ml), i.e. no false negatives were found. However, in these cases, the diagnosis was already evident from basal serum calcitonin (S-CT), which up to now has been our most sensitive diagnostic technique for MCT. 19 first-degree relatives of patients with Sipple's syndrome presented no signs of MCT. In 14 of these delta-CT240 was normal ("healthy relatives"), but in 5 it was slightly elevated, intermediate between the controls and the MCT patients. These 5 borderline cases were more sharply delineated from normal by delta-CT240 than by S-CT. Thus our calcium infusion test seems to be the most sensitive method for early diagnosis of occult MCT. We recommend the calcium infusion test for: (a) screening for MCT in all Sipple relatives with normal or only slightly elevated basal S-CT, (b) postoperative control in both sporadic and hereditary MCT, (c) investigation of supposed non-MCT tumours with calcitonin production.


Cardiac arrhythmias, electrolytes, and digoxin concentration in plasma and urine in patients treated with digoxin.

Cardiac arrhythmias, digoxin concentration in plasma and urine, digoxin and creatine clearances, electrolytes in plasma and in erythrocytes, and subjective symptoms have been carefully studied for 5 consecutive days in 19 patients with definite or suspected digitalis intoxication. The digoxin treatment was discontinued during the observation period. Eleven controls without any signs of toxicity were similarly followed on unchanged maintenance dosage. All patients were independently classified as toxic or non-toxic from the follow-up of extended ECG recordings and subjective symptoms. In 9 definitely toxic patients a plasma digoxin concentration 3.1 plus or minus 0.7 ng/ml was found, as compared to 1.4 plus or minus 0.5 ng/ml for the 11 controls. In the suspect toxic group 1.5-3.9 ng/ml was found. The high digoxin level in the toxic group corresponds to a low digoxin clearance. In the toxic patients cardiac arrhythmias were related in most cases to a plasma digoxin level above 2.5 ng/ml and usually disappeared when the concentration had decreased below this. Suspect toxic patients, classified as probably non-toxic, and controls had with two exceptions plasma digoxin levels below 2 ng/ml. It is suggested that digitalis toxicity should be considered at a plasma digoxin concentration above 2 ng/ml. It must be stressed that this limit is not absolute and is affected by, among other things, a disturbance of intra- and extracellular electrolytes.


Registration of sinus node recovery time in patients with sinus rhythm and in patients with dysrhythmias.

Sinus node recovery time (SRT) after rapid atrial pacing has been recorded in 66 patients, 28 with coronary heart disease, 11 with advanced AV block, 10 with sick sinus syndrome and 17 with paroxysmal tachyarrhythmias. In patients with a normal functioning sinus node SRT was related to the basal heart rate. On an average SRT was 130% of the basal P-P interval with an upper limit of 160%. In patients with a presumed normal atrial function the mean SRT was found to be 1 080 msec, with an upper limit of 1 500 msec. This corresponds with previously published observations. In all 5 patients examined, beta-receptor blockade (propranolol 5 mg i.v.) prolonged SRT. The prolonged SRT was related to sinus bradycardia. Verapamil (Isoptin 5 mg i.v.) had no effect on SRT in the 7 patients examined. The observation of an SRT of more than 1 500 msec indicates a poor sinus node function. Recording of a normal SRT, however, cannot exclude a sinus node dysfunction, as normal SRT is occasionally found even in patients with a clinically proved dysfunction.


Turnover of plasma cholesterol in patients with cholesterol gallstones.

Following the i.v. injection of about 30 muCi of 1-alpha-2-alpha-3H-cholesterol, the specific activity decay of plasma cholesterol has been analysed in terms of a 2-pool model in eight patients with radiolucent gallstones and two healthy controls. In each subject some kinetic parameters were calculated, including the input into and the size of the rapidly exchangeable cholesterol pool. The results were compared with those in 16 controls from another study. Statistical analysis failed to demonstrate significant differences in any of the parameters between the gallstone patients and the combined controls, indicating that patients with cholesterol gallstones have normal input into and size of the rapidly exchangeable cholesterol mass. The conclusion is discussed in relation to similar studies, and it is speculated that gallstone patients may have decreased absorption of exogenous cholesterol.


Anorexia nervosa and the frequency of sex chromatin-positive cells.

Five consecutive cases of anorexia nervosa in women have been investigated for variations in the frequency of sex chromatin-positive cells. The results showed a statistically signifcant relation between body weight and the frequency of sex chromatin-positive cells, the amount of sex chromatin increasing with rising body weight. These findings are difficult to explain but the results might conceivably be used, at least in some cases, as an index of changing basal biological functions in anorexia nervosa.


Total disappearance of a fatal pulmonary embolus during streptokinase therapy of an iliofemoral thrombosis.

During streptokinase treatment of an iliofemoral thrombosis, a formerly healthy man developed clinical signs of major pulmonary embolism. In spite of all attempts at resuscitation, the patient died after 1.5 hours. The autopsy showed no signs of remaining thrombus or emboli. The probable explanation is that the thrombus had partially been lysed and that the remaining parts formed an embolus large enough to cause considerable haemodynamic changes which could not be influenced. Lysis continued pre- and postmortally and was complete at the time of autopsy.


Neurophysiology of photically induced epilepsy in Papio papio.

This chapter critically reviews arguments supporting the role of the frontal cortex in light-sensitive epilepsy of the baboon Papio papio in the light of the most recent neurophysiological research. In particular, it is known that spontaneous or ILS-induced paroxysmal discharges, as well as generalized seizures, originate in the frontorolandic cortical region. In this region during ILS, neurons behave in the same manner as hyperexcitable neurons in focal epileptogenic lesions of animals and man. Aso, section of the corpus callosum causes deterioration or even destruction of the synchronization that exists naturally between the two frontorolandic areas. Lastly experimental focal irritative lesions enhance light sensitivity if they are located in the frontorolandic region and inhibit it if they are located in the occipital cortex. Opposing these arguments are those that support the important role the occipital cortex plays, since its ablation makes excessive light sensitivity in the baboon disappear. Studies of the primary and nonprimary visual messages and pathways have also contributed evidence. In particular, demonstration of the existence of large numbers of direct occipitofrontal connections may help reconcile the two opposing arguments. Other evidence favoring the role of the frontal cortex is furnished by the still fragmentary studies on activation of the motor pathways and by studies in neuropharmacology. The significance and value of this type of epilepsy as an animal model of the generalized reflex epilepsies of man are discussed.


Afterdischarges elicited by electrical thalamic stimulation in the hemicerebellectomized baboon.

Electrical stimulation of the ventrolateral (VL) nucleus of the thalamus was performed on hemicerebellectomized baboons. Stimulation was delivered in volleys of 40 to 60 Hz lasting 5 to 25 sec, and at intensities ranging from 1 to 6 mA (width of shock 0.5 to 5 msec). Similar parameters of stimulation produced asymmetrical motor and electrocortical responses. When the normal VL nucleus was stimulated, these responses were tonic or tonic-clonic. When the VL nucleus deprived of its cerebellar afferents was stimulated, the tonic-clonic responses were followed by afterdischarges appearing in the EEG which persisted after cessation of stimulation. The role of the cerebellum in the lowering of the excitability threshold of some structures, particularly the VL nucleus, is discussed, as are the systems likely to play a role in producing various clinical responses.


Action of dopamine receptor agonists in forebrain and hypothalamus: rotational behavior, ovulation, and dopamine turnover.

An ergolene derivative having a piperazine-phenyl side chain instead of a peptide side chain causes rotational behavior in experimental rats and appears to activate mainly limbic DA receptors when given in vivo, in contrast to amino acid ergot alkaloids, which appear to activate all DA receptors when given systemically. Theophyllamine and caffeine were found to cause considerable enhancement of the action of DA formed from DOPAP AND DA receptor agonists such as apomorphine, piribedil, and amino acid alkaloids on supersensitive DA receptors. Many DA receptor agonists such as apomorphine, piribedil, and CB 154 have in common the property to induce hypothermia in mice, an effect that may be related to actions on limbic DA receptors. Many DA receptors agonists such as apomorphine, piribedil, ergocornine, and CB 154 are able to block ovulation in immature rats treated with PMS. It is likely that this blockade is related to activation of a DA receptor in the median eminence controlling LRF secretion. DA receptor agonists antagonize sexual activity in the female rat, whereas DA receptor blocking agents enhance it. DA neurons may therefore subserve an inhibitory role in the control by hormones of sexual behavior. It is of considerable interest that there appear to exist inhibitory DA receptors with regard to both LRF secretion and sexual behavior.


Platelet 5-hydroxy-tryptamine in thrombotic and non-thrombotic diseases.

It is generally accepted that platelets from the main constituent of a thrombus. Experimental work has shown that 5-hydroxy-tryptamine (5 HT) in a concentration of 0.06 mg/ml produces clumping of the platelets. In view of this it was decided to estimate platelet 5 HT in thrombotic and non-thrombotic diseases. Thirty-five patients were investigated. Estimations of 5 HT were made on washed platelets rather than platelet-rich plasma which has been used in previous studies. Three groups were recognized on the basis of platelet 5 HT values. The first group consisted of five subjects who were clinically asymptomatic at the time of investigation but died 24 to 48 hours later and were shown at autopsy to have deep-vein thrombosis and pulmonary embolism; they had the highest level of platelet 5 HT. The second group comprised eight patients with cerebral thrombosis whose platelet 5 HT ranged between 1529 and 2183 ng/10-9. There were 22 subjects in the third group (11 apparently normal and 11 with different pathologies). Their platelet 5 HT ranged from 611 to 877 ng/10-9 and did not vary in the different pathological conditions studied. Since the highest level of platelet 5 HT was observed in patients prior to the formation or embolization of a thrombus, it is suggested that this may have some role in initiating thrombus formation.


The New Patient Index - a method of measuring the activity of day hospitals.

The workload of three Day Hospitals was studied during 1973 and a simple mathematical calculation, the New Patient Index, devised to enable rapid assessment of function and activity to be made. This calculation gives a more accurate assessment of function than the conventional returns of total attendance or of new patient attendance for it takes size and activity into account. It can be measured over any period of time, weekly, monthly or yearly. It is proposed that a calculated New Patient Index should be included in all future reports on Day Hospitals. In addition it is suggested that the calculation should be used to plan Day Hospital development based on the discerned needs of the elderly in an area or district.


An evaluation of the intravenous vitamin D test in geriatric patients with suspected osteomalacia.

In 30 elderly patients, the measurement of serum phosphate levels before and after intravenous vitamin D3 was not found to be a useful way of predicting the presence or absence of osteomalacia as determined by bone biopsy.


Influence of age and sex on the calcification of rat aorta in relation to bone mineralization.

Thoracic aortas of pvg rats accumulated Ca (analysed by flame spectrophotometry) throughout mature life, with females having slightly higher levels than males at each age interval studied. Femur Ca concentration was similarly elevated in female rats, and was maintained fairly constant in both sexes after 19 weeks of age. Femur Mg and K levels showed an over-all decrease with age; whilst the Na concentration fell up to 19 weeks, and then decreased steadily. It was concluded that a simple shift of Ca from the ageing skeleton into soft tissues cannot adequately account for aortic physiosclerosis.


Cardiac effects of carotid sinus massage in old age.

The effects of carotid sinus massage in aged subjects with a high incidence of arteriosclerosis are described. In 71 men and 315 women tested, a slowing of more than 10 per cent of the heart rate was found in 25 per cent of the men and 19 per cent of the women, which is not of statistical significance in relation to sex. Only men showed a significant increase with age and the women had a significant preponderance of a right-sided response. The technique was found to be safe, although a review of reported side-effects suggests care is advisable and carotid compression must not occur. The findings are discussed in relation to those reported in younger subjects and in carotid sinus syndrome with syncope. The fact that men have an acquired increase in response in old age, which is not seen in women, may be a factor of importance in the explanation of why carotid sinus syncope is almost always seen in men. Carotid sinus sensitivity appears to diminish in old age and some of the ageing factors which might influence the carotid sinus reflex are examined.


Growth hormone secreting carcinoma of lung and hypertrophic osteoarthropathy.

Plasma Human Growth Hormone (HGH) was raised in a patient with bronchial carcinoma and hypertrophic pulmonary osteoarthropathy before radiotherapy to the tumour. Though the soft-tissue swelling and pain of hypertrophic osteoarthropathy disappeared two to three weeks after radiotherapy to the carcinoma the HGH plasma levels were still very high at two months and came back to normal levels at six months and remained so at one year. It is suggested that ectopic production of HGH by the tumour in this case was not responsible for the changes of hypertrophic osterarthropathy.


The clinical significance of systolic murmurs in the elderly.

A group of 278 patients, over the age of 60 years, and representative of geriatric and general medical admissions to the District General Hospital in Banbury, Oxforshire, was studied to correlate the prevalence of systolic murmurs to age, sex, cardiac failure, ischaemic heart disease, dysrrhythmias, hypertension, peripherial vascular disease and anaemia. The object was to establish the clinical significance of these murmurs and test a postulate that they could not be dismissed as benign. Seventy-five per cent of the murmurs were judged to be aortic and 12 per cent mitral in origin. The prevalence of systolic murmurs increased with age from 32 per cent at 60-64 years to 57 per cent over 85 years, and was greater in females (44 per cent) than in males (34 per cent). The presence of systolic murmurs was related to the presence of cardiac failure, ischaemic heart disease, dysrrhythmias, hypertension, peripheral vascular disease and anemia. Only 8 per cent of patients with systolic murmurs had none of the above-mentioned six cardiovascular abnormalities compared with 36 per cent of patients without such a murmur, while multiple cardiovascular abnormalities were also commoner in the former group. The mortality rate in hospital was similar for patients with or without a systolic murmur.


Overlap problems in counting fibers.

The probabilities of certain errors in counting fibers due to accidental overlaying during sampling are calculated and shown to be significant. Justification is given for simple rules to get agreement in counting between microscopists.


Asbestos control in steam-electric generating plants.

A program to control industrial work exposures to airborne asbestos fibers is presented. The program is consistent with OSHA standards, and with current good industrial hygiene practice. The program includes methods of problem evaluation, the establishment of effective corporate standards, and provisions for environmental and medical surveillance. Hazard control measures and techniques are discussed and their merits related.


Analytical methods used in a study of coke oven effluent.

In a coke oven study conducted by NIOSH, selected chemical analyses of airborne particulates, vapors, and metals in the emissions from five coke ovens were done. Eight sampling procedures and seven analytical techniques were used to analyze samples collected for the study. Six of the analytical methods used are discussed.


Classification of analytical methods.

The ideal analytical method is one which has been thoroughly evaluated, collaboratively tested by a number of laboratories, and established by long usage. The development of such procedures is time consuming and expensive. However, a classification scheme which recognizes that methods may be used which have not been fully evaluated or collaboratively tested is useful. A scheme with five classes which has been applied to NIOSH analytical methods is presented. It recognizes that many analytical methods have been developed, that other agencies and organizations have examined the literature and published methods, and that unproved or suggested method may be the only information available.


Industrial hygiene and safety controls at a 1.5 MeV electron beam accelerator facility.

This paper discusses radiological safety measures built in to a 1.5 MeV electron beam accelerator at the General Motors Research Laboratories. The accelerator is used to study the interaction of electrons with plastic materials. The safety features described represent the type of precautions taken over and above legal requirements and include the results of experience gained in other installations.


The alveloar deposition of inhaled plutonium aerosols in rodents.

The alveolar burden following nose-only aerosol exposure of rodents to highly toxic radioactive materials depends upon the percentage of the inhaled aerosol that is deposited beyond the animals' ciliated epithelium. The quantity inhaled was estimated from the product of the aerosol concentration (nCi/liter), the exposure time (minutes) and the mean minute volume (liter/min) of the animals. For rats exposed to Pu(NO3)4 and sacrificed within an hour, the mean alveolar deposition was 19.2 plus or minus 9.19% for 36 groups of both -239Pu and -238Pu. No important correlations between any of the measured parameters and this initial percentage deposition were observed, in contrast with the results for -239PuO-2 deposition measured in rats sacrified 24 or 48 hours postexposure. In these, the aerosol activity median aerodynamic diameter (AMAD) was strongly correlated with aerosol concentration and percentage deposition (mean-7.9 plus or minus 3.9% for 32 groups) with AMAD over the range of 1.5 to 4.5 mum. The 200-fold lower mass concentration of -238Pu compared with -239Pu for a given activity level may explain the fact that the AMAD was correlated with concentration for -239Pu oxide and nitrate, but not for -238Pu compounds.


Sulfamic acid cleaning solution for 4,4'-methylene-bisorthochloroaniline (MOCA).

Laboratory tests have shown that an aqueous solution of 1.0 wt.% sulfamic acid-0.5 vol.% surfactant can be used for decontaminating MOCA-contaminated surfaces to less than the analytical detectable limits for MOCA, without any flammability hazards. Nuclear magnetic resonance spectra have shown that a different compound is formed when sulfamic acid is reacted with MOCA, as evidenced by the disappearance of the NH2 peak from the MOCA spectrum.


Identification of polcyclic aromatic hydrocarbons in semi-reinforcing furnance carbon black.

A weighed amount of a "special" semi-reinforcing (SRF) carbon black, made in 1964 and not considered to be typical for furnace blacks, was extracted with triple distilled benzene for 24 hours. The separation of carcinogens from the benzene extract was achieved by gas chromatography on a 5 ft x 0.25 inch stainless steel column packed with 3% OV-1 on chromosorb W. The chromatogram yielded 20 peaks. These peaks were collected, eluted and identified by (a) comparison of retention times, (b) peak enhancement technique, and (c) comparison of their excitation and fluorescence spectra with those of known polycyclic aromatic hydrocarbons (PCAH) standards. The PCAH's identified in SRF-carbon black were: anthracene, phenanthrene, fluoranthene, pyrene, benzo(mno)fluoranthene, chrysene, 1,2-benzanthracene, 9,10-dimethyl-1,2-benzanthracene, 1,2-benzopyrene, 3,4-benzopyrene, perylene, o-phenylene pyrene 1,2-benzoperylene, anthanthrene, and coronene. Of these, 1,1-benzanthracene, 9,10-dimethyl-1,2-benzanthracene, 3,4-benzopyrene and o-phenylene pyrene are known carcinogens. These and others have also been quantitated.


Recovery of blood lead concentration and of red cell 8-aminolevulinic acid dehydrase activity in dogs following return to normal diets after 75 weeks of lead feeding.

Blood lead concentration and red cell delta-aminolevulinic acid dehydrase (ALAD) activity were determined at intervals for eight months after symptom-free dogs, which had received 100 ppm or 500-1000 ppm of lead, by weight, in their diets for 75 1/2 weeks, were returned to a lead-free diet. Statistical treatment of the data disclosed a linear relationship between the logarithm of blood lead concentration or of ALAD activity and the logarithm of time (experimental week) during the recovery period. The calculated regressions predict that recovery of ALAD will occur before recovery of the blood lead concentration. Predicted recovery times depend on the levels selected as those which must be attained for recovery to be complete, as well as on the dosage of lead. The logarithm of the slope of the ALAD recovery regression of the individual dog has a linear relation to the percentage reduction in ALAD due to the lead, the regression accounting for 92% of the variance in the recovery rates. The slope of the blood lead recovery regression has a linear relation to the increase in blood lead for the dogs which received the low lead diet, but not for those which received the high lead diet.


The effect of particle size on absorption of inhaled lead.

Baboons were exposed to dust clouds of Ph3O4 of different size distribution but of the same total gravimetric concentration. Blood samples were taken immediately after each exposure of 4 hours and the total blood lead was determined. The exposure to the lead-bearing dust was stopped after four weeks, but the blood sampling continued for another six weeks. Graphs are presented comparing the patterns of lead absorption obtained with different sized lead particles. The coarser lead particles resulted in a higher blood lead concentration than the finer.


Biological monitoring for industrial exposure to tetraalkyl lead.

An evaluation of the Chamber Works control program was made relative to the 1967 Threshold Limit Value (ACGIH) for tetraalkyl lead compounds. Results from fixed station samplers throughout the manufacturing areas had not correlated well with routine medical examinations and urinary excretion levels for lead. Similarly there was no correlation of fixed station results with urinary excretion rates. This suggested that personnel monitoring procedures would be necessary to obtain a valid evaluation of the highly variable ambient work atmosphere. No correlation could be established between personnel and fixed station monitor results; however, the mobile units gave significantly higher values. An approximately linear relationship between breathing zone lead levels and urinary excretion was found when the sum of the weekly average organic and inorganic lead TLV coefficients were related to the corresponding average urine excretion.


Mask design considerations.

Mask design should be based more strongly on physiological data obtained from working individuals. This paper is a compendium of pertinent information as well as a guide to better design. An indication of the trends of current research is also given.


Effects of a physical activity program on middle-aged, sedentary corporation executives.

This study determined the effects of controlled physical training program on resting heart rate, blood pressure, serum cholesterol and body weight in middle-aged, sedentary, corporation executives. Two groups were established: an active group consisting of invited subjects hat exercised on a regular basis, and a comparison group consisting of subjects that were invited to use the facility but did not. Both groups were classified by the Medical Deartment as being "clinically normal." The training intensity of the active group was at 65% to 85% of age predicted maximum heart rates as established by the Tennessee Heart Association. Each exercise session was closely monitored by the subjects and by the instructors. Training continued for 24 months. Statistical analysis indicated that resting heart rate, systolic blood pressure, and serum cholesterol were significantly reduced after the training as compared to the comparison group. However, there were no significant changes in diastolic blood pressure or body weight.


Epidemiological implications of environmental cadmium. I. The probable utility of human hair for occupational trace metal (cadmium) screening.

Some of the problems involved in the use of human hair sample as an indicator of trace metal exposure are discussed. The significant correlations of hair cadmium level with the respective kidney (r equals .52) and liver (r equals 0.36) levels in selected autopsies, and the fact that hair samples can distinguish between occupational and non-occupational exposure (t28 equals 4.88) in a New Jersey community are advanced as arguments in favor of hair sampling. The hair samples were washed with sodium lauryl sulphate, deionized water and acetone and then dried. All the samples were ashed at 450-500 degrees and analyzed by atomic absorption spectrophotometry.


Echocardiographic criteria for aortic root dissection.

Echocardiographic findings from 10 patients without clinical indications of aortic root dissection or aortic valve disease from 1 patient with angiographic confirmation of aortic root dissection are reported and compared. Previously reported echocardiographic findings were confirmed in the patient with aortic root dissection. These include (1) a widened posterior or anterior aortic wall, or both; (2) parallel motion of the separated margins of the aortic walls; and (3) aortic root dilatation (42 mm or more at end-systole). However, all three findings were also noted in 5 of the 10 patients without clinical indications of aortic root dissection or aortic valve disease, and at least two of the three findings were noted in the remaining 5 patients. Echocardiographic detection of aortic root dissection appears to be most reliable when clinical indications of the anomaly are present.


Radiographic appearance of the thorax in systolic click-late systolic murmur syndrome.

The posteroanterior and lateral chest X-ray films of 64 consecutive patients with an isolated systolic click (55 patients) or a systolic click with a late systolic murmur (9 patients) showed a striking frequency of thoracic skeletal abnormalities. There were 50 female and 14 male subjects. The average age of the female subjects was 36.7 years (range 13 to 67), that of the male subjects 39.7 years (range 17 to 56). Seventy-two percent of the female and 78 percent of the male subjects had an anteroposterior/transverse thoracic ratio less than the mean ratio in a small population. Bony abnormalities such as pectus excavatum, straight thoracic spine and scoliosis occurred alone or in a combination in 31 of the 50 female patients (62 percent) and in 8 of the 14 male patients (57 percent). Overall, 39 of the 64 patients (61 percent) had at least one of the skeletal abnormalities. Scoliosis occurred in 25 subjects (39 percent) and was mild in 19. A "straight back" was found in 15 (23 percent) and pectus excavatum in 7 patients (11 percent). The explanation for these findings is not apparent. Thoracic cage abnormalities should be included as one of the nonauscultatory features of the systolic click-late systolic murmur syndrome.


Thoracic skeletal abnormalities in idiopathic mitral valve prolapse.

Idiopathic prolapse of the mitral valve is a common disorder, but many cases are clinically subtle. Thoracic skeletal abnormalities, reported recently to accompany the syndrome, may serve as an easily identifiable clinical indicator. The prevalence of these abnormalities was defined in 24 patients with proved prolapse of the mitral valve. The valvular syndrome was defined clinically, by echocardiography and, in seven cases, by left ventricular angiography. The skeletal deformities were defined clinically and radiographically. Pectus excavatum was present in 62 percent of the patients, "straight back" in 17 percent and severe scoliosis in 8 percent. Eighteen of the 24 patients (75 percent) had a definite thoracic skeletal deformity. The association of idiopathic prolapse of the mitral valve with these skeletal deformities may represent a forme fruste of Marfan's syndrome. Patients with "straight back" and pectus excavatum should be examined clinically and perhaps by echocardiography to exclude idiopathic prolapse of the mitral valve; when murmurs are present, a diagnosis of "pseudoheart disease" should not be made before mitral valve prolapse has been excluded.


Termination of ventricular fibrillation in dogs by depolarizing a critical amount of myocardium.

The role of a critical myocardial mass required to maintain ventricular fibrillation initiated by rapid ventricular pacing was studied by two methods in dogs placed on total cardiopulmonary bypass. In the first method, depolarization of a limited myocardial mass was accomplished by injecting potassium chloride into one or two coronary arteries. Injection of potassium chloride simultaneously into the left circumflex and left anterior descending coronary arteries abolished ventricular fibrillation more often than did injection into any other single or combination of two coronary arteries (P less than 0.0001). Ventricular fibrillation could not be reinitiated as long as the left ventricle remained inexcitable. Immersing the heart in a solution of potassium chloride or injecting the solution into the right and left ventricular cavities failed to terminate ventricular fibrillation. The second method evaluated the amount of current necessary to terminate ventricular electrodes, between two left ventricular electrodes and between one right ventricular and one left ventricular electrode. Electrical shocks of equal magnitude terminated ventricular fibrillation most often when those shocks were delivered between an electrode located at the right ventricular apex and an electrode located at the posterior base of the left ventricle, and least often when the shock was delivered between two right ventricular electrodes. Successful defribillation results when a critical amount of myocardium becomes depolarized by either potassium chloride or electrical discharge; depolarization of every cell in both ventricle is not necessary to terminate ventricular fibrillation in the entire heart.


Influence of sympathetic tone on ventricular fibrillation threshold during experimental coronary occlusion.

The effects of increased and decreased cardiac sympathetic tone and coronary occlusion on ventricular fibrillation were determined in 14 open chest dogs anesthetized with sodium pentobarbital. Heart rate was kept constant by pacing the right atrium at cycle lengths of 500 msec. Ventricular fibrillation threshold was measured by delivering 350 msec trains of constant current stimuli with a frequency of 100 hertz and 2 msec duration. The minimal current of the train that induced fibrillation was taken as the ventricular fibrillation threshold. In seven animals, the effects of stellate stimulation were studied. Ventricular fibrillation threshold was measured during control periods, after 2 minutes of cornoary occlusion, after 2 minutes of stellate stimulation and after 2 minutes of stellate stimulation and coronary occlusion. Coronary occlusion alone decreased ventricular fibrillation threshold an average of 35 percent of control valvues and stellate stimulation alone decreased the threshold an average of 42 percent of control values. The combination of both these interventions decreased ventricular fibrillation threshold an average of 63 percent of control values. The effects of stellate ablation were studied in seven animals. Ventricular fibrillation threshold was measured during control periods, and during coronary occlusion before and after stellate ganglionectomy. Stellectomy increased the threshold an average of 31 percent above control values. After stellectomy, coronary occlusion decreased ventricular fibrillation threshold by only 11 percent of control values, a value 26 percent higher than the threshold during coronary occlusion before stellectomy. These findings may have therapeutic implications for the management of arrhythmias in patients with acute myocardial infarction or some forms of central nervous system disease.


Effect of manganese chloride and Verapamil on automaticity of digitalized Purkinje fibers.

The effects of manganese chloride (MnCl2) and verapamil on automaticity of digitlazied Purkinje fibers were studied using conventional microelectrode techniques. The stduied wer made in isolated, spontaneously beating Purkinje prearations. Quabain alone consistently increased the automatic rate, whereas no such increase was observed when the preparations were superfused with a mixture of ouabain adn MnCl2. MnCl2 was also shown to be effective is suppressing the enhanced automaticity induced by ouabain. Mncl2 alone did not have a significant effect on the spontaneous rate of Purkinje fibers. The effect of verapamil was similar to that of MnCl2 in preventing and suppressing the ouabain-induced increase in automaticity. MnCl2 and verapamil have been shown to inhibt tha slow inward calcium current of cardiac fibers. The results therefore suggest that  an inward calcium ion current may play a role in the development of digitalis-induced increase in the stope of phase 4 depolarization in Purkinje fibers.


Use of a balloon-tipped flotation electrode catheter for cardiac mounting.

A new balloon-tipped flotation catheter equipped with two pairs of electrodes has been developed for simultaneous monitoring of cardiac rhythm and hemodynamics as well as for temporary emergency atrial, ventricular and atrioventricular sequential pacing. Experience in 43 patients demonstrates the following: (1) The catheter can be passed and positioned with the tip in the pulmonary artery or its branches at the bedside with the use of fluoroscopy as easily as the standard (Swan-Ganz) catheters. (2) With the catheter in the proper position ans with the use of appropriate filters (proximal, 50 to 300 hertz; distal, 15 to 300 hertz), the intracavity  electrograms recorded from the proximal and distal pair of electrodes provide characteristic high right atrial and right ventricular signals, virtually free of noise artifact, baseline drift and respiratory variation, that are particularly suitable for automated on-line monitoring of cardiac rhythm. (3) When indicated, atrial, ventricular or atrioventricular sequential pacing can be initiated without delay. (4) Large artifact-free right ventricular intracavitary signals can be used for reliable and consistent operation of any device requiring QRS triggering mechanisms. (5) Monitoring of pulmonary arterial or pulmonary capillary wedge pressure and withdrawal of blood samples from the central circulation is possible. This device can be particularly useful in patients with hemodynamic difficulties as well as arrhythmias.


Pseudomalfunction of a Beall mitral valve prosthesis in the presence of paravalvular aortic regurgitation.

Premature closure of a Beall mitral valve prosthesis is described in a patient with aortic prosthetic paravalvular regurgitation. Differentiation from valvular malfunction and diagnostic confirmation by means of cinefluoroscopy and simultaneous electrocardiography are discussed.


Limitation of the surface electrocardiogram in diagnosis of atrial arrhythmias. Further observations on dissimilar atrial rhythms.

Electrophysiologic studies with recordings of multiple intracavitary electrograms were performed in two patients with atrial dysrhythmias. In Case 1 the arrhythmic pattern in the surface electrocardiogram resembled atrial flutter. Electrophysiologic studies revealed the arrhythmia to be paroxysmal left atrial tachycardia, with separation of left and right atrial components of the P wave by an isoelectric period secondary to marked interatrial conduction delay. In Case 2 the surface electrocardiogram indicated paroxysmal atrial tachycardia with block. Electrophysiologic studies revealed right atrial standstill with atrial inexcitability and two dissimilar rhythms involving the left atrium. The electrocardiograms did not accurately reflect atrial arrhythmias in these two patients and only multiple direct recordings permitted the correct diagnoses. New electrophysiologic observations concerning intraatrial block and dissimilar atrial rhythms are presented.


"Paradoxical" prolongation of sinus nodal recovery time after atropine in the sick sinus syndrome.

A case of symptomatic sick sinus syndrome is presented with confirmation of sinus nodal dysfunction established by functional testing. The validity of such provocative testing and the criteria for abnormality are discussed. A newly recognized, seemingly "paradoxical" and potentially detrimental effect of atropine noted in this patient is examined. Despite an increase in sinus rate and an improvement in sinoatrial conduction time after administration of atropine, a markedly prolonged sinus recovery time after rapid atrial pacing occurred, and atrial quiescence for more than 10 seconds was seen. Possible electrophysiologic mechanisms for this phenomenon, such as decreased atriosinus entrance block, concealed sinoatrial reentry or enhanced intranodal depolarization, are discussed and potential clinic correlates are made.


Reproduction of the canyon bat, Pipistrellus hesperus, in southwestern United States.

The reproductive biology of the bat Pipistrellus hesperus was investigated histologically using animals obtained from nature at monthly intervals throughout the year. The female shows proestrous morphological changes in late summer and autumn, which continue until early spring. Insemination is probably effected several times during proestrous, since both sexes are intermittently active throughout this period (August--April). Permanent arousal from torpor and return to normal metabolism in the spring results in ovulation. Both ovaries are functional and both uterine horns may be utilized. P. hesperus is monestrous; two young per bat is usual. The male spermatogenic cycle is initiated in late June and the first sperm are available for ejaculation in September. Some sperm remain in the seminiferous tubules until early March. The epididymides also serve in sperm storage with the caput emptied by late February and the cauda in April. Leydig cells are largely nonsecretory from March through July, a few are secretory in August and most are secretory in September and October. Active cells gradually decline in number until few are secretory in late March. Accessory sex glands are functionally cyclic: they are small from April through August, hypertrophy in September, and gradually involute to the resting stage through March, to achieve total involution in April. The penis, similar in structure to that of other vespertilionids, is thought specialized to insure effective insemination.


Cytodifferentiation of striated duct cells and secretory cells of the convoluted granular tubules of the rat submandibular gland.

The structural and functional development of the striated ducts and convoluted granular tubules (CGT) of the rat submandibular gland (SMG) were studied by electron microscopy and alkaline protease chemistry. Development of the SMG was followed from 14 days of gestation through 30 weeks of age. The specialized morphology of the basal aspect of the striated duct cells arises from cellular extensions which are first seen at 20 days of gestation. These processes elongate and intertwine with similar processes from adjacent cells, and as the cells enlarge the processes are compressed together giving the appearance of "infolding" of the basal plasma membrane. Mitochondria migrate to the basal part of the cell and are seen in close relationship to the cellular extensions throughout the development of these cells. Development of the striated duct is complete by one week after birth. The CGT develop from the proximal portions of intralobular striated ducts. At one week after birth, cells of the proximal striated duct demonstrate apical vacuoles. By two weeks after birth these vacuoles are replaced by distinct zymogen-like granules. There is a progressive accumulation of large numbers of secretory granules in the CGT cells as the animals age. However, rough endoplasmic reticulum is a relatively inconspicuous cellular component throughout development. The accumulation of alkaline protease activity in the gland closely parallels the pattern of granule accumulation.


Effects of a progestogen and a sequential type oral contraceptive on plasma vitamin A, vitamin E, cholesterol and triglycerides.

Fasting blood samples were taken from 13 college students who had never been on oral contraceptives in two menstrual cycles. During the first cycle, the control cycle, each girl donated three blood samples; the first sample was given between days 1 and 5, the second sample between days 13 and 17, and the third sample between days 22 and 26 of the menstrual cycle. In the second menstrual cycle, the experimental cycle, nine girls were given Micronor, a progestogen type oral contraceptive and four girls were given Ortho-Novum SQ, a sequential type oral contraceptive. Four blood samples were obtained from each of the subjects: the first three samples were obtained in the three periods corresponding to those in the control cycle, and the fourth was taken 2 days after the subjects had stopped taking the oral contraceptive. Results showed that estrogen significantly raised plasma vitamin A and triglycerides. The progestogen, at low concentration, had little or no effect on these two lipid materials. At a higher concentration the progestogen enhanced the effect of the estrogen on plasma vitamin A and triglycerides. These effects were extended to at least 2 days after subjects had ceased taking the oral contraceptive. Plasma vitamin E levels in the subjects given Ortho-Novum SQ, were consistently but not statistically higher in the experimental cycle than in the control cycle. The correlation coefficient between vitamin E and triglycerides was statistically significant while those between the vitamin A and vitamin E and between vitamin A and triglycerides were not. Cholesterol was not affected by either Micronor or Ortho-Novum SQ.


Mucosal uptake in vitro of cholesterol from bile salt and surfactant solutions.

That bile salts are required for intestinal absorption of cholesterol is well known, but the mechanism of action is elusive. Substitution of other surfactant micelles and inclusion of fatty acid or monoglyceride variably influenced sterol transport. In this study, rat jejunal mucosal sheets were exposed for 1-2 min to 10 mM micellar solutions of taurodeoxycholate, dodecylsulfate, Tween 80 or cetyltrimethylammonium bromide containing cholesterol, 0.25 mM. Monoolein and/or oleic acid were variably added. Cholesterol influx was insignificant in all solubilizers without additives. With taurodeoxycholate, addition of monoolein progressively enhanced influx from 13 nmoles/cm-2 per hour to 29 nmoles/cm-2 per hour (0.67-5.4 mM monoglyceride). Oleic acid, 3 mM, was as effective as 5.4 mM monoolein. Oleic acid, 3 mM, added to monoolein 3 mM maximized influx (42 nmoles/cm-2 per hour). With cetyltrimethylammonium bromide, monoolein 0.67 mM enhanced influx to 13 nmoles/cm-2 per hour but further additions of monoolein with or without oleic acid had no added effect. Additives had no material effect on the insignificant influx from the other anionic or nonionic surfactants. These results are not explained by differences in cholesterol, monoolein or oleic acid partition or in micellar sizes. Specific interactions of bile salt and fatty acid or monoglyceride with the plasma membrane are postulated in cholesterol absorption.


Zinc metabolism in aminonucleoside-induced nephrosis.

Nephrosis was induced in Sprague-Dawley rats in two separate studies by injections of aminonucleoside with sacrifice of animals on days 20 and 54, respectively. Experimental animals in both studies showed the typical findings of nephrosis, i.e., hypoalbuminemia, hypercholesterolemia, and proteinuria. Biochemical findings included hypozincemia and hyperzincuria. A significant correlation between hypozincemia and hypoalbuminemia was noted in the short-term study. Proteinuria occurred on the 10th day in the short-term study and the 15th day in the long-term study and increased quantitatively over the remaining days. The hyperzincuria and proteinuria correlated significantly in the long-term study. Measurements of tissue zinc revealed no change in testes and kidney in the short-term study. Kidney and muscle zinc were increased, testicular zinc was unchanged and femur zinc was decreased in the long-term study. Our conclusions are that in the aminonucleoside induced nephrosis of the rat: 1) hypozincemia occurs probably as a result of hypoalbuminemia, 2) the hyperzincuria is likely due to proteinuria and 3) zinc deficiency is not observed in nephrotic rats who receive ample zinc in their diet and who are observed up to 6 weeks.


Lactose intolerance among Mexican Americans.

Thirty-three Mexican Americans between the ages of 9 and 60 were interviewed and tested for lactose intolerance. The participants of the study included 16 children and 17 persons not related by birth, including the parents of the children. Determination of lactose intolerance was based on a rise of less than 25mg/100 ml of blood glucose as measured by an Ames Dextrostix/Reflectance Meter following consumption of a lactose load. Forty-seven percent of the 17 nonrelated Mexican Americans were lactose intolerant. There was a marked relationship between low rise in blood glucose and symptoms  of diarrhea, flatulence, and distention. Sixteen children from four families had an incidence of 50 per cent intolerance. The findings of intolerance in two successive generations of three families and in both sexes of the families adds support to the contention that lactose intolerance has a genetic basis, without sex predilection.


Effect of feeding polyunsaturated fatty acids with a low vitamin E diet on blood levels of tocopherol in men performing hard physical labor.

A diet made low in vitamin E by elimination of foods considered good sources of the vitamin was fed for 13 months to two groups of men engaged in strenuous labor. With a daily average dietary intake of about 9.4 mg of total tocopherols, a progressive decline in blood levels of tocopherol from 1.42 to 0.81 mg/100 ml was observed in the five control subjects. The test group of 30 men received a daily supplement of tocopherol-stripped safflower oil containing 88 g of polyunsaturated fatty acids and 2.3 mg of tocopherols. Average blood plasma levels of tocopherol in this group dropped rapidly from an initial  value of 1.01 to about 0.5 mg/100 ml within 5 months and remained relatively stable thereafter. No muscular weakness or other physical symptoms were reported.


Findings relating to goiter and iodine in the Ten-State Nutrition Survey.

Examinations for thyroid size were carried out on 35,999 individuals in the Ten-State Nutrition Survey. Overall goiter prevalence was found to be 3.1 per cent with the higher prevalence of goiter among adolescents and adults. Females of all ages had a higher prevalence of goiter than did males. No consistent regional pattern of the occurrence of goiter was observed. Urinary iodine excretion values used to estimate iodine intake indicated very few persons with excretion values suggesting iodine deficiency. No association between goiter and low iodine excretion was observed. On the contrary, a higher prevalence of goiter was found among persons excreting high levels of iodine. There is no indication from this study of widespread, iodine-deficiency goiter.


Tocopherols and polyunsaturated fatty acids in human tissues.

Five tissues from three adults who died suddenly and three adult cancer victims were analyzed for alpha- and gamma-tocopherols and fatty acids. When compared with two reports in 1949 and 1958, the three presumably normal subjects had alpha-tocopherol concentrations in liver, muscle and adipose tissue in about the same range as earlier, but heart was twice as high and lung was three times higher than earlier. The content of gamma-tocopherol in all tissues was considerably higher than in 1949 or 1958. Tissues from cancer patients were no lower in alpha-tocopherol than tissues from normal subjects. Adipose tissue from three of the six subjects contained linoleic acid exceeding 15 per cent of total fatty acids. Tocopherols in these subjects, expressed on a tissue weight or tissue lipid basis, were not remarkable. The molar ratio of polyunsaturated fatty acids to alpha-tocopherol in heart and lung was calculated and its possible use in evaluating vitamin E status is discussed.


Combined zinc and iron compared with iron supplementation of diets of 6- to 12-year old village schoolchildren in southern Iran.

The effects of supplementation of the diets of 6- to 12-year-old children in a village near Shiraz in Iran with zinc plus iron or iron alone, together with the indispensable amino acids in the form of egg white protein, vitamins, minerals, and corn oil have been evaluated. Initially 48 of 59 children had zinc concentrations below the minimum found in well-nourished persons. Eight months of supplementation with zinc plus iron (20 mg daily of elemental zinc as carbonate and 20 mg ferrous iron as fumarate) failed to stimulate growth or bone development or to bring about an increase in plasma zinc concentrations. However, supplementation with iron in the above amount was associated with an acceleration of growth in height and weight. The persistence of low concentrations of zinc in plasma and the failure of supplemental zinc to stimulate growth are attributed to the poor availability of both dietary and supplemental zinc resulting from sequestering action of fiber and phytate present in large amounts in the unleavened whole meal bread consumed by villagers. In addition, the results suggest that simultaneous administration of iron and zinc supplements may impair utilization of the metals.


Effect of hydrogenated fat on the plasma cholesterol and triglyceride levels of man.

A group of 33 adult males was fed for 21 days a formula diet that supplied 38 per cent of their calories as fat. The fatty acid composition of the diet was 25 per cent saturates, 16 per cent polyunsaturates and 58 per cent monounsaturates. All of the unsaturated acids were in the cis configuration. The subjects were then divided into two groups. One group of 17 men continued on the same diet. In the diet of the remaining subjects, 80 per cent of the dietary fat was replaced with a hydrogenated fat. Over 60 per cent of the monounstaurated acids and approximately one-half of the polyunsaturated acids of the diet of this latter group were in the trans configuration. Except for the presence or absence of trans acids, the fatty acid intakes of the two groups were the same. Over the 4-week period that the two diets were consumed, the group receiving the hydrogenated fat showed no change in plasma cholesterol or triglyceride levels relative to the subjects consuming the unhydrogenated fat. It is concluded that the effect of a hydrogenated fat on blood lipid level is determined by its fatty acid composition and this effect is not altered by the isomeric form of the unsaturated acids.


Assessment of vitamin B 6 status. Studies on pregnant women and oral contraceptive users.

The vitamin B6 status of 10 pregnant women (third trimester), 9 oral contraceptive agent users, and 12 notnpregnant women (controls) was investigated over a 10-week period by means of the erythrocyte glutamate-oxaloacetate transaminase (E-GOT) activation test and by measurements of whole blood pyridoxal phosphate levels. Blood pyridoxal phosphate levels in oral contraceptive agent users (7.6 plus or minus 1.1 ng/ml) were significantly lower than in the control group (9.6 plus or minus 1.7 mg/ml)indicating a relative vitamin B6 deficiency. Pyridoxal phosphate levels in pregnant women(5.1 plus or minus 1.3ng/ml) were even lower; in fact, no overlap was found in individual mean values between the pregnant and control groups. The E-GOT activation test did not indicate a vitamin deficiency in the pregnant women or in oral contraceptive agent users and the E-GOT activation factor did not correlate with blood pyridoxal phosphate levels unless results obtained after pyridoxine hydrochloride (20 mg/day) administration were included. The E-GOT activation test appears to be a poor indicator of vitamin B6 status, except in pronounced deficiency as it is less responsive to vitamin depletion than blood pyridoxal phosphate levels, and suffers from relatively large variations in individual control values. This may be a result of factors unrelated to vitamin B6 as blood pyridoxal phosphate levels remained fairly constant in the individuals investigated.


Effects of carbohydrate restriction on glucose tolerance of normal men and reactive hypoglycemic patients.

Normal individuals ingesting a low carbohydrate diet frequently develop an impairment of glucose tolerance as measured by the oral glucose tolerance test; most of these diets, however, have been high in fat content. Our present studies demonstrate that a low carbohydrate diet (57 g/day) did not impair the glucose tolerance of normal men if the fat content was similar to values on a standard (301 g/day) carbohydrate diet. However, a low carbohydrate diet did lead to impaired glucose tolerance when the fat content was 16 per cent higher than on the control diet. Thus our present and previous studies demonstrate that normal men maintain normal glucose tolerance on low carbohydrate diets and suggest that the deterioration of the glucose tolerance observed on high fat diets is related to the  increased fat content rather than to the reduced carbohydrate content of these diets. Seven patients with reactive hypoglycemia were exquisitely sensitive to carbohydrate deprivation. Whereas the glucose tolerance tests of normal men were not altered by a low carbohydrate, high protein diet, a significant deterioration of glucose tolerance occurred when reactive hypoglycemic patients were changed from control diets to low carbohydrate, high protein diets. These hypoglycemic patients also showed an exaggerated deterioration of the glucose tolerance after a 48-hour fast when compared tothe response of normal men. Our observations suggest that a low carbohydrate, high protein diet is not the best therapeutic diet for certain patients with reactive hypoglycemia because this diet does not provide symptomatic improvement and, in addition, leads to impaired glucose tolerance.


Distribution of tocopherols in human plasma and red blood cells.

The content of various tocopherols was determined in normal plasma and red blood cells. alpha-Tocopherol concentrations ranged form 6.6 to 15.0 (mean 9.6) mug/ml in plasma and from 0.9 to 1.8 (mean 1.4) mug/ml in red blood cells. gamma-Tocopherol ranged from 0.7 to 2.7 (mean 1.6) mug/ml in plasma and fron 0.1 to 0.4 (mean 0.24) mug/ml in red blood cells. Only a minute amount (smaller than 0.3 mug/ml) of each of alpha-tocotrienol, beta-tocopherol, gamma-tocotrienol and delta-tocopherol was found in plasma but none in red blood cells. No delta-tochotrienol was detected in either plasma or red blood cells. Of the total tocopherols, alpha form accounted 83 per cent in plasma and 87 per cent in red blood cells and gamma from represented 13 per cent in each system. The recovery of added 14-C-alpha-tocopherol averaged 87 per cent and 69 per cent, respectively, for plasma and red blood cells. All alpha-tocopherol in the red blood cells was found to be localized in the membrane fraction.


Prevention of folate deficiency by food fortification. VII. The use of bread as a vehicle for folate supplementation.

Bread fortified to contain a daily dose of 900 mug folic acid was administered to patients in late pregnancy. The patients receiving the bread showed significant rise in red cell folate concentration. The rise was similar to that observed in women receiving a daily dose of 300 mug of folic acid in tablet form. It is concluded that bread may be used as a vehicle for folic acid fortification.


Coronary heart disease: the zinc/copper hypothesis.

Epidemiologic and metabolic data are consanant with the hypothesis thata metabolic imbalance in regard to zinc and copper ia a major factor in the etiology of coronary heart disease. This metabolic imbalance is either a relative or an absoulte deficincey of copper characterized by a high ratio of zinc to copper. The imbalance results in hypercholesterolemia and increased mortaility die to coronary heart disease. The imbalance can occur due to the amounts of zince and copper in human food, to lack of protective substances in food or drinking water and to alterations in physiological status that produce adverse changes in the distribution of zinc and copper in certain important organs. Because no other agent, with the possible exception of cholesterol, has been related so closely to tisk, the ratio of zinc to copper may be the preponderant factor in the etiology of coronary heart disease.


Use of height-arm circumference measurement for nutritional selectivity in Sri Lanka school feeding.

In order to maximize the impact of limited resources available for the government of Sri Lanka/CARE school feeding program, a nutrition survey was carried out in 1973 using the measurements of arm circumference for height of 1,122,773 school children aged 6-12 years. The results of the survey provided a score of the incidence of malnutrition in each government primary school and schools with the highest percentage of malnutrition were selected as eligible for the feeding program. The height-arm circumference technique as found to be a valid tool for diagnosing malnutrition when compared with either weight-height-age or clinical assessment. This technique requiring only measuring tapes, was found to be rapid, economical, and highly practical for field situations as a device for nutritional selectivity. The survey findings revealed that 40 per cent of the primary school population were malnourished.


Taste thresholds for salt in fasting patients.

Since it has been controversial whether in man changes in taste sensitivity for salt occur in relation to changes in extracellular volume, as has been described in animals, we assessed saline acuity in human volunteers undergoing a predictable pattern of external sodium balance. Our results demonstrate that taste thresholds for salt did not vary despite oppositely directed changes in renal sodium excretion and sodium balance.


Zinc deficiency occurring in females. Report of two cases.

The syndrome of dwarfism, hypogonadism, iron-deficiency anemia and geophagia, first reported in 1960 from Iran, was thought to be limited to males. In 1971-1972 two females with the same clinical features were observed over a 14-month period. The anemia responded rapidly to iron. Growth and sexual development occurred promptly when 120 mg of zinc sulfate was administered daily in conjunction with a well-balanced diet and iron supplement. This diet prior to the addition of zinc sulfate, resulted in gradual but much slower growth and sexual development. Observations in these two patients provide confirmation of the occurrence of human zinc deficiency in females, which responds to large doses of zinc salt.


Reducing diets in rats.

Adult obese rats were restricted to equal intakes provided by four diets which varied widely in protein, fat and carbohydrate content. Loss in body weight and body fat was similar in all groups. The only significant dietary effect observed was a modest increase in the body protein content of the animals fed the high protein diets. Low carbohydrate--high fat--high protein diets, as expected, showed no advantage as reducing diets when compared to other diets on an equal calorie basis.


Effect of oral contraceptives and pyridoxine on the metabolism of vitamin B6 and on plasma tryptophan and alpha-amino nitrogen.

The effect of supplementary pyridoxine on the metabolism of vitamin B6 as well as plasma tryptophan and alpha-amino nitrogen was determined in women using oral contraceptive agents. Ten women who were taking oral contraceptive agents and 11 who had never taken them served as subjects. Blood from the various biochemical measurements was drawn from fasting subjects before and after they had received an oral dose of 50 mg of pyridoxine-HCl daily fo 2 days. The use of oral contraceptive agents had no effect on the levels of blood vitamin B6, plasma pyridoxal phosphate, and plasma tryptophan. The activity of erythrocyte glutamic oxaloacetic transaminase was higher (P less than 0.05) in the oral contraceptive agent users than in the nonusers but the stimulation in vitro by pyridoxal phosphate was similar for the two groups. Plasma alpha-amino nitrogen was slightly lower in the oral contraceptive agent users than in the nonusers, but the difference was not statistically significant. The rise in blood vitamin B6 in response to pyridoxine was similar in the two groups, but the rise in plasma pyridoxal phosphate tended to be lower in the oral contraceptive agent treated subjects. Following pyridoxine supplementation, the basal activity of erythrocyte glutamic oxalocetic transaminase increased (P less than 0.01) in both groups of subjects and the stimulation in vitro by pyridoxal phosphate decreased correspondingly. Plasma tryptophan and alpha-amino nitrogen were unaffected by the supplementary pyridoxine.


Variation in plasma folate levels among groups of healthy persons.

Levels of plasma folate, erythrocyte folate and serum vitamin B12 were measured in 106 essentially healthy persons grouped both as to race and economic--educational status. Whereas the mean values of the three assays did not differ significantly among groups, values of plasma folate below the usual limits of normal were more prevalent in the migrant worker and urban clinic groups. Persons with low plasma folate levels did not have symptomatic deficiency as evaluated by hematocrit, peripheral blood smears and erythrocyte folate levels. The interpretation of the plasma folate requires reference values from a healthy population selected to be comparable to the study group. The diagnosis of deficiency, or at least the degree of deficiency, requires clinical and laboratory evaluations beyond the plasma folate.


Plasma triglyceride clearing in obese children.

In 13 obese children plasma triglyceride concentrations were found to be significantly elevated, while plasma cholesterol concentrations were normal. In the hypertriglyceridemic obese children, the plasma fractional triglyceride removal, measured by the intravenous fat tolerance test, was significantly reduced. These abnormalities reverted to normal in 8 patients retested after weight loss. Plasma postheparin lipoprotein lipase activity was found to be increased and significantly related to the degree of obesity. As to carbohydrate metabolism, a decreased glucose tolerance and hyperinsulinemia were found. Hyperinsulinemia reverted to normal during dietary restriction, glucose intolerance did not.


Effect of oral contraceptives and vitamin B6 deficiency on carbohydrate metabolism.

Oral glucose tolerance, urinary xanthurenic acid excretion, and plasma pyridoxal phosphate concentrations were determined in nine women taking oral contraceptives and in four controls. The tests were repeated after 4 weeks ingestion of a vitamin B6-deficient diet, and again after pyridoxine supplementation. Vitamin B6 deficiency, as judged by an increased xanthurenic acid excretion and reduced plasma pyridoxal phosphate, was associated with a deterioration in the glucose tolerance of the contraceptive steroid-treated group despite normal or elevated plasma insulin levels. This abnormality was reversed by pyridoxine. There was no change in the glucose tolerance of the vitamin B6-deficient controls. The observed pyridoxine-responsive alteration in carbohydrate metabolism may involve the complexing of insulin with xanthurenic acid with a consequent loss of biological activity. In addition, oral contraceptives may enhance gluconeogensis.


Sweat nitrogen losses by and nitrogen balance of preadolescent girls consuming three levels of dietary protein.

A nitrogen balance study was undertaken to determine the effects of three levels of nitrogen intake on the loss of nitrogen through sweat and to assess the impact of sweat nitrogen on the protein needs of preadolescent girls. Values were determined through the collection of 24-hour, total body sweat samples from 15 healthy girls with a mean age of 8 years, 7 months. Mean height and weight of the subjects were 132 cm and 28.9 kg, respectively. Mean sweat nitrogen losses, collected under uncontrolled environmental conditions, were 201 mg, 263 mg and 319 mg/day on 34 g, 57 g and 88 g of protein intake. The environmental conditions throughout the study remained fairly constant. Mean nitrogen balances per day were 0.04 g, 0.55 g and 1.42 g on the respective levels of nitrogen intake, with the inclusion of sweat nitrogen loss, however, a negative nitrogen balance per day was found in 8 and 2 subjects on 34 g and 57 g protein intake. After considering nitrogen retention of 0.3 g which has been recommended by NRC for the minimum nitrogen allowance for growth of preadolescent children, protein intakes higher than that recommended by the NRC-RDA for preadolescent girls may be required  for support of normal growth.


Epidemic dropsy in New Delhi.

Forty-five cases of epidemic dropsy were studied from an epidemic in New Delhi. Argemone oil contamination was found in the mustard oil used for cooking. Sanguinarine was detected in the eight urine samples collected within 2-3 weeks of onset of dropsy and its concentration ranged from 0.4 to 3.6 mug/100 ml. Three of the 18 sera were positive for sanguinarine, the concentration being 1.2, 1.6 and 3.6 mug/100 ml. The clinical manifestations and epidemiological factors were studied. Edema of the legs was the most consistent clinical finding, and was present in all the patients. In contrast to the earlier epidemics, three striking features were pigmentation in 33%, hair loss in 77.7% and nontender hepatomegaly in 24.4% of cases. A follow-up of 10 months showed almost complete recovery in all.


Rapid and portable methods of lactose tolerance test administration.

Abbreviated, portable methods of lactose tolerance test administration were investigated. Results obtained with the Ames Reflectance Meter/Dextrostix system for blood glucose determination during lactose tolerance testing were compared with those obtained from a standard method, the AutoAnalyzer. Subjects who had maximum blood glucose rises below 20 mg/100 ml were considered to have a flat lactose tolerance curve and were designated lactose nondigesters. Results of the two methods were very similar for determination of maximum rise in blood sugar over fasting level, for obtaining values of individual blood sugar determinations, and for diagnosis of lactose nondigesters. The effect of omission of the final blood sample on tolerance test results was examined. It was found that maximum rises in blood glucose occurred before the final sample in 31 of 35 cases on the AutoAnalyzer and in 26 of 27 cases on the Reflectance Meter. In no case did omission of the final sample change the results of the lactose tolerance test.


Enteropathy in adult protein malnutrition: a review of the Cali experience.

Since 1964, 41 patients with strictly defined, severe primary (dietetic) protein malnutrition have been studied under metabolic ward conditions during prolonged periods, initially on a low (20 g) and later on a high (100 g) protein diet. Clinical, nutritional, hematological, intestinal absorptive and histological studies were performed in the malnourished state, during and after protein repletion. Classical signs and symptoms of malnutrition, lasting for at least 4 months, were present in most patients. Mild diarrhea was frequent. All were normoblastically anemic, hypoproteinemic, and hypocholesterolemic; serum folate values were normal or low but serum B12 values were normal or high. Liver biopsy showed fatty liver in the cases where it was performed. Mild malabsorption was detected in over one-half of the patients, with moderate intestinal radiological abnormalities. Malabsorption was independent of concomitant folate deficiency. All the clinical, absorptive and histological abnormalities reversed with treatment consisting only of a high protein diet. In addition to protein lack, another factor has to be invoked in the pathogenesis of the intestinal abnormalities present in severely malnourished adults from rural areas in the tropics.


Enteropathy in adult protein malnutrition: ultrastructural findings.

As part of a comprehensive study in adult patients with severe primary protein malnutrition, jejunal ultrastructural studies have been performed in nine adults in the malnourished state. Malnutrition was severe in all. D-Xylose malabsorption and abnormal fecal fat excretion were present in most. The main ultrastructural abnormalities encountered were: microvillar abnormalities such as shortening, diminished numbers, abnormal positioning, branching, and mesalike fusion of the microvilli; and abnormalities in the lamina propria characterized by deposits of osmiodense material and collagen fibers below the basement membrane of the epithelial cells and of the capillaries. None of the aforementioned findings were noted in our control cases. These ultrastructural alterations of severely malnourished adults are nonspecific, since they have already been described in other enteropathies frequently encountered in the tropics.


Enteropathy in adult protein malnutrition: light microscopic findings.

Light microscopy evaluation of the intestinal abnormalities seen in 35 severely malnourished adults revealed changes which are common to other well-documented enteropathies. These included shortening, widening and fusion of the villi, lost convolution of the nuclear line, and diminished epithelial cell height. With Masson's trichrome stain, dense material was seen to have accumulated in a subepthelial location in villi (as described in other enteropathies), in crypts, and perivascularly around the capillaries of the lamina propria. Two findings however appear to characterize the severely malnourished state: a consistent, significant reduction of intestinal mucosal thickness, and in many cases atrophy of the crypts. Statistical analysis of the total mucosal thickness data does not justify five but rather three histological categories. With protein repletion as the sole therapeutic modality, 17 patients in which adequate biopsy samples were available at its completion showed significant amelioration of the aforementioned histological abnormalities, as well as normalization of their previous absorptive defects. The mild enteropathy of severe protein malnutrition must be considered in the differential diagnosis of malabsorption in a tropical setting.


Failure of methylhistidines to inhibit platelet aggregation at concentrations found in uremic plasma.

Methylhistidines are among the amino acids which are present in increased concentrations in the plasma of severely uremic patients who may have a hemorrhagic diathesis. Histidine contains an imidazole ring, and our previous work has shown inhibition of collagen-induced platelet aggregation by imidazole in concentrations as low as 0.5 mM. Collagen-induced, adenosine diphosphate-induced, and norepinephrine-induced platelet aggregation were tested in platelet-rich plasma by a turbidimetric technique after incubation of the plasma with varying concentrations of the methylhistidines for 1 hour. Platelet aggregation was unaffected by methylhistidine concentrations up to 0.6 mM. Only norepinephrine-induced platelet aggregation was slightly inhibited at a concentration of 4.7 (mM far higher than found in uremic patients). The imidazole ring as a portion of the methylhistidine molecule appears to have lost much of its effect on platelet aggregation.


Paroxysmal cold hemoglobinuria. Transmission and scanning electron microscopy features of erythrocytes.

Djaldetti, Meir, Elion, Dorith, Bessler, Hana, and Fishman, Pnina: Paroxysmal cold hemoglobinuria. Tranmission and scanning electron microscopy features of erythrocytes. Am J Clin Pathol 63. 804-810, 1975. The case history of a patint with paroxysmal cold hemoglobinuria of the chronic iduipathic type is reported. The patient showed a marked dependency on the external temperature, with severe hemolytic anemia and hemoglobinuria during the winter. Examination of the erythrocytes with the transmission electron microscope showed abnormal forms identified as ropalocytes, whereas examination with the scanning electron microscope revealed "holes" in the erythrocytes. (Key words: Paroxysmal cold hemoglobinuria' Ultrastructure of erythrocytes.


Orbital and conjunctival involvement in multiple myeloma. Report of a case.

Benjamin, Ivy, Taylor, Herbert, and Spindler, James: Orbital and conjuctival involvement in multiple myeloma. Report of a case. Am J Clin Pathol 63: 811-817, 1975. Orbital and conjunctival involvement in multiple myeloma are rare. In most reported cases of multiple myeloma with orbital involvement proptosis has been the initial manifestation that has led to diagnosis of the disease. Our case represents and example of terminal involvement of the orbit and conjunctiva, causing proptosis. The minimal conjunctival changes were the first indication of neoplastic proliferation of plasma cells in this location and, presumably, the orbit.


Lymph-node infarction in two young men.

Benisch, Barry M., and Howard Rudolf G.: Lymph-node infarction in two young men. Am J Clin Pathol 63: 818-823, 1975.  Two cases of massive lymph-node infarction in young men are described.  Both patients had fever and lymphadenopathy and findings that suggested the possibility of viral infection.  Follow up has revealed both patients to be asymptomatic, with lymphadenopathy, and with normal laboratory findings.


A simple finger-prick method of screening for abnormal hemoglobins.

Thambipillai, Shanthi, and Senewiratne, B.: A simple finger-prick method of screening for abnormal hemoglobins; Am J Clin Pathol 63: 836-840, 1975.  Two simple methods of hemoglobin electrophoresis of samples obtained by finger prick are described. The methods do not involve venipuncutre, centrifugation, or the preparation of a hemolysate, and can be carried out on starch gel or cellulose acetate membranes. The specimen can be collected even by non-medical personnel and sent by post to the laboratory. Alternatively, electrophoresis can be carried out in the field and the results obtained within 20 minutes. Both methods are suitable for population screening and pediatric studies. The method will detect structurally abnormal hemoglobins only.


An improved method for the quantitation of A2 hemoglobin utilizing cellulose acetate electrophoresis and densitometry.

An improved method of A2 quantitation by cellulose acetate electrophoresis is describes. Densitometry is performed on uncleared membranes. The height of the peak obtained for the A2 band is compared with a standard curve derived from peaks obtained by serial dilutions of hemoglobin. Noral A2 hemoglobin as measured by this method is 2.55 percent plus or minus 0.60 (2 S.D.). Twenty patients samples were run in parallel with a column chromatographic method. Eight samples were found to contain elevated A2 levels by the column method.  The same eight samples were correctly identified by the electrophoretic technic.


Hepatitis B (surface) antigen testing by radioimmunoassaymexperience in a very large volunteer donor population.

The results of hepatitis B surface antigen (HBs-Ag) testing in a large volunteer blood donor population are described. Counterelectrophoresis and three versions of solid-phase radioimmunoassay technic are compared and evaluated. Initial results suggested that the radioimmunoassay technic are compared and evaluated. Initial results suggested that the radioimmunoassay technic detected more than five times as many reactive donors as did counterelectrophoresis. The specificity of the radioimmunoassay technic has been increased by successive modifications, and recent results show that the technic detects 73 percent more reactive donors than does counterelectrophoresis. Not all of these reactions are specific, and it is estimated that the true gain in detection of HBsAg carriers is 49 percent of the value found by counterelectroesis. The incidence of HBsAg carriers in the America Red Cross donor population is about 1.25 per 1,000.


Papillary cystadenoma lymphomatosum (Warthin's tumor) in patients in a general hospital over a 24-year period.

One hundred thirty-seven Warthin's tumors from 120 patients seen during a 23 1/2 year period were studied as two groups. The first group consisted of 32 tumors removed by the otolaryngology department. Material from these cases was re-examined microscopically for evidence of tumor occurrence within lymph nodes located inside and outside the parotid gland. This group of 32 tumors was also studied as part of the second group, 105 additional lesions removed by the surgery department. Data on patient age, sex, and race, as well as tumor multiplicity, location, and size were incorporated into a single statistical analysis. Seventy-two percent of the tumors in the first group were intranodal in location. Second primary Warthin's tumors occurred in 13 (11%) of the patients. Eight occult tumors were identified, and their importance is discussed. A single Negro, a man, was found among 118 patients. The observed frequency of the tumor was twentyfold less than expected among the Negro population.


Epidermoid carcinoma with sebaceous differentiation in the vallecula. Report of a case.

The report deals with a case of epidermoid carcinoma of the vallecula with widespread sebaceous differentiaton. The sebaceous areas were first observed in a cervical lymph-node metastasis, which preceded the discovery of the primary lesion. No similar lesion has been described. Recent literature dealing with extracutaneous sebaceous lesions is cited.


Effectiveness of the nitroblue tetrazolium test in demonstrating reduced bactericidal activity of polymorphonuclear neutrophils in schistosomal hepatosplenomegaly and ascites.

The nitroblue tetrazolium (NBT) test was carried out on blood from ten normal individuals and 20 schistosomal patients, ten of whom had hepatosplenomegaly and ten hepatosplenomegaly and ascites. The test revealed defective neutrophils in patients who had hepatosplenomegaly accompained by ascites. The phagocytic and bactericidal effects from five of each of the two groups of patients; results substantiated tose obtained by the NBT screening test. The NBT screening test thus proved useful in detecting acquired defective function of neutrophils in a helminthic parasitic disease that is accompanied by frequent bacterial infections.


An international laboratory survey.

Lyopholized and liquid aliquots of human serum and blood were distributed in 1973 and 1974 to 50 international medical laboratories that took part in a pilot study sponsored by the College of American Pathologists (CAP) and the Commission on World Standards of the World Association of Societies of Pathology (COWS/WASP). The results were compared with data derived from more than 4,000 United States laboratories that received the same samples. Sodium, potassium, urea nitrogen, glucose, hemoglobin and hematocrit assays show a strikingg similarity in mean values when the World group (COWS/WASP) is compared with participants in the United States. The results suggest that laboratory testing in the international group follows the pattern seen in the United States. The study measures differences and similarities and the collected data serve as a springboard for discussion on international standards of laboratory testing.


The first year of the toxicology program.

The CAP Toxicology Survey Program's initial year is reviewed. Four series of samples, each consisting of five specimens with approximately 12 different drugs, were sent to almost 200 participants and as many as seven referees. They reported the presence or absence of more than 16 different compounds, and identified specific barbiturates when present. In each series, two serum samples were for qualitative identification and quantitative analysis. The remainder were urine samples for qualitative analysis. The aim of the survey is to enhance the "current state of the art" among participants. Drug-abuse toxicology and therapeutic monitoring of drugs were given priority. Clinically relevant samples reflecting current drug abuse, especially mixed-drug abuse, were provided, including serum for quantitative determination as is required in treatment of barbiturate overdose and for therapeutic drug monitoring. The Committee has interacted with participants by critiques of surveys, by questionnaires, and by responding to queries from participants.


CAP survey to assess the extent of stray light problems in precision spectrophotometry.

When the absorbance at 240 nm. of a solution of sodium iodide was measured by 159 laboratories using narrow-band-pass spectrophotometers, 15% reported results that suggested a problem caused by stray light. The laboratories were also requested to measure the absorbance at 240 nm. of solutions of acid potassium dichromate and alkaline potassium chromate. The laboratories that had stray-light problems reported absorbance results that were skewed in distribution and showed low mean values and wide instrument-to-instrument variation. The laboratories without stray light problems reported results with less instrument-to-instrument variation, the results followed a symmetrical distribution, and the mean of the results provided an accurate estimate of the absorbance of the solutions.


Progress and analytic goals in clinical chemistry.

The data that have been accumulated by the Survey program of the College of American Pathologists for analysis of 12 serum constituents for the five-year period 1969-1973 are reviewed. The data include approximately 2 million individual analyses provided by the majority of the clinical laboratories in the United States. The data show clear evidence of progressive improvement. The values reported by the participants for each analysis have agreed more closely in each successive year. The improvements have stemmed partly from improved performance of individual methods and partly from increased use of methods with good precision. Closer standardization between laboratories may have played a role. The findings are used for proposing a set of goals for the analysis of these constituents in serum. Comparison of the goals with the actual levels of current performance shows that for many analyses the current levels are adequate, while for others the current levels fall short of the desired goals. Achieving the goals from some analyses may be beyond the present limits of the technology of clinical laboratory analysis.


Studies of fibrinogen measurement in the CAP survey program.

A review of the College of American Pathologists' Surveys experience in fibrinogen testing from 1967 to 1974 is reported. Trends in fibrinogen methodology and the emergence of a consensus choice of the modified thrombin time method are documented. The reasons for these changes from former methods are discussed.


The partial thromboplastin time in the CAP survey program.

Analysis of the data for the 1969 to 1973 CAP Surveys of proficiency in partial thromboplastin time (PTT) determination indicates more than desirable variability in this measurement. Non-activated procedures show greater interlaboratory variability than activated methods; therefore, they may be preferable for routine use. It is likely that many laboratories have not determined their own upper limit of normal for their PTT system and thus have received unacceptable evaluations in the Surveys. It also was determined that many laboratories do not closely follow the manufacturer's directions, especially in regard to incubation times and calcium concentration of the recalcification solution.


Hyperactivity in children.

The various childhood problems that are often subsumed under the heading of "hyperactivity" occur in various combinations and, apparently, for various reasons. The designation does not define a homogeneous group of children, does not consistently point to a common cause, and has treatment implications only in the sense that multiple simultaneous approaches must typically be considered. Stimulant drugs, which seem frequently to be used for control of so-called hyperactivity, are an inadequate treatment when used alone, have a number of poorly studied effects, some of which are apparently negative, and may obscure problems other than the hyperactivity itself, which then may be ignored. There is some evidence now available that classroom learning does not improve with drug treatment despite common assumptions to the contrary.


Polycystic disease and hepatic fibrosis in children. Renal function studies.

Renal function studies were done in five children with infantile polycystic disease (IPCD)of kidneys and liver and in four with congenital hepatic fibrosis (CHF). Glomerular filtration rate was reduced in all IPCD patients and in two of four CHF patients. Urinary concentrating ability following water deprivation and vasopressin administration was impaired in all IPCD patients and in three of four CHF patients. During control period, all patients had asymptomatic metabolic acidosis with total carbon dioxide content less than or equal to 20.5 millimols/liter, and net acid excretion (NAE) was reduced in all but one. Ammonium chloride was administered to seven patients; NAE increased in all, but the increments were subnormal in four. The inability to excrete maximally concentrated urine and an adequate amount of net acid may best be explained by abnormal tubular structure or alterations in medullary architecture secondary to progressive scarring, or both.


Non-health professionals and the school-age child. Treatment of minor acute health problems.

In order to meet the minor acute health needs of the school-age child in an effective and efficient manner, school health workers were trained to follow standards of problem solving with the aid of a problem-specific reporting form for seven common minor acute problems. During the operation of the program, the workers displayed a high degree of compliance with standards of the problem-solving process. The program resulted in a substantial reduction in the work load for the minor acute problems, and there was a reduction in the number of unnecessary trips to the clinic for minor problems.


Constrictive pericarditis in children.

We observed five cases of constrictive pericarditis (CP) during a 12-year period, and studied the clinical findings, usual causes, and hemodynamic findings. There are two variants of CP: a chronic form, which is usually of unknown cause, and a rapidly developing form, which follows an attack of effusive pericarditis. A high index of suspicion is necessary to establish the diagnosis of CP both in children with a prolonged course of ascites and failure to thrive and in children with effusive, usually purulent, pericarditis. Although CP is rare in childhood, it should be easily recognized and curative surgical therapy should be rapidly initiated.


Free serum thyroxine level and basal metabolic rate. Aids to diagnosis in malnutrition and small-for-gestational-age dwarfism.

Measurement of the basal metabolic rate (BMR) and the total and free serum thyroxine values in response to feeding are aids in the diagnosis of growth failure. Infants with small-for-gestational-age dwarfism gained weight poorly in the hospital, had a low BMR before and after spontaneous or induced weight gain, and a normal serum thyroxine value. Infants with linear growth failure due to chronic malnutrition had a normal BMR but a low serum thyroxine value that rose to normal with weight gain; infants with clinical signs of recent weight loss had a low BMR and a low serum thyroxine value, both of which rose to normal with weight gain. Increases of the BMR were sharp and very rapid; they preceded the rise of the serum thyroxine value in some cases.


Dietary fluoride intake from supplements and communal water supplies.

Artificial fluoridation of communal water supplies has resulted in 50% to 60% reductions in dental caries experience accompanied by very little fluorosis. Although vitamin-mineral fluoride supplements also have resulted in significant caries reductions, data are not readily available in the literature in regard to enamel fluorosis in the permanent dentition of children who have received supplements in early infancy. In comparison to estimates of fluoride intake from communal water supplies, the recommended dosage from fluoride supplements results in daily doses that may be two to six times greater, on the average, for the infant less than age 6 months and three times greater for the average 3-year-old. Estimates from both sources bear careful consideration in light of available knowledge and are not necessarily indications for a revision in presently acceptable practice.


Hypertrophic osteoarthropathy without pachydermia. Idiopathic form.

A 3-year-old boy had primary hypertrophic osteoarthropathy without pachydermia. This case is similar to several others previously described, and it could possibly represent a distinct nosological form of osteoarthropathy.