Physiological response to exercise after space flight--Apollo 14 through Apollo 17. Submaximal exercise stress tests were conducted preflight and postflight on the Apollo 14-17 crewmen. A bicycle ergometer was utilized to evoke target heart rates up to 160 beats/min while respiratory gas exchange, blood pressure, and cardiac output were measured. Three preflight tests were conducted during the month prior to flight to establish baseline values for postflight comparisons. Tachycardia was evidenced at rest and during exercise immediately postflight. This transitory tachycardia compensated for reduced stroke volume. Systolic blood pressure was reduced during exercise stress, but no consistent changes were observed in diastolic blood pressure. With the exception of the Apollo 15 crewmen, all crewmen had returned to preflight response levels by the day of following recovery. No changes were observed in mechanical or respiratory efficiency immediately postflight.


Control of health hazards from airborne lasers. The use of lasers in tactical military aircraft present eye hazards to personnel in aircraft and on the ground. Biomedical scientists and engineers are often asked for advice for controlling these hazards. Methods are given for applying ocular exposure criteria to the solution of practical field safety problems. Laser pointing accuracy and the extent of hazardous specular reflections from flat glass and from standing areas of water are the principal determinations required to develop safe laser operations. Special considerations may be required for scanning lasers and laser arrays.


Head diffraction effects on ear-level hearing aids. In this paper, head baffle and head shadow effects were measured at a front-oriented and at a back-oriented microphone in a hearing aid casing when worn by human subjects and when placed on a dummy head. Some differences in head baffle and head shadow effects were observed for the front-and back-oriented microphones in that greater head baffle effects were observed at the front microphone than at the back microphone while the reverse was true in terms of head shadow effects. Results obtained with the hearing aid mounted on a dummy head were similar in some respects and in other respects they differed from those observed when the hearing aid was worn by six subjects. Comparison of the results obtained in this study with the data of WIENER measured at the entrance to the ear canal indicated smaller head baffle effects but larger head shadow effects at the hearing aid microphone than at the canal entrance. Finally, it is suggested that reproduction of frequencies above 2 000 HZ and that a resonance peak at about 3 000 HZ in the frequency response curve of a hearing aid may be beneficial to the wearer.


Response of local vascular volumes to lower body negative pressure stress. The present study involved an intravenous injection of radio-active iodinated serum albumin, equilibration of this isotope within the vascular space, and the continuous measurement of isotope activity over selected anatomical areas before, during and following multiple human LBNP tests. Both rate and magnitude of vascular pooling were distinctly different within each of five selected lower body anatomical areas. In the upper body, all areas except the abdomen showed depletions from their resting vascular volumes during LBNP. The presence of uniquely different pooling patterns in the lower body, the apparent stability of abdominal vascular volumes, and a possible decrease in cerebral blood volume during LBNP represent the major findings of this study.


Comments on the relations between auditory fatigue and iris pigmentation. It has been reported that subjects with highly pigmented irises (brown) experience significantly less temporary threshold shift (TTS) than subjects with less pigmented irises (blue), and that those with green-gray pigmentation display intermediate amounts of TTS. TOTA and BOCCI noted the high correlation between the melanin content in the stria vascularis and that found in the pigmentation of the iris; they attributed their TTS differences across eye colour to the protective effects of melanin. TTS data are reported in this paper as a function of eye colour for exposure stimulus parameters almost identical to those used by TOTA and BOCCI (1 000 HZ at 110 dB SPL for 3 min). The present results do not support the hypothesis that individuals with highly pigmented irises (brown-eyed) are more resistant to auditory fatigue than those with less pigmentation of the iris (blue-eyed). Median TTS at 20 sec post-exposure among brown, green-gray, and blue iris categories did not differ by more than 1.8 dB, and the median TTS at 2 min post-exposure among those iris categories did not differ by more than 0.2 dB.


Noise-excluding enclosure for audiometry. Excessive ambient noise adversely effects the efficiency of hearing conservation programs. Noise-excluding enclosures generally reduce the masking effects of such noise more effectively than standard earphones only. Research has shown, however, that pure-tone thresholds obtained with some enclosures may not be valid. The present study examines one particular type of enclosure, the Audiocup. The results revealed (1) that pure-tone thresholds obtained with Audiocups are almost identical to those measured with standard earphones only and (2) Audiocups more effectively reduce the masking influence of white noise. It is concluded that Audiocups may be used for screening and for threshold audiometry in less than ideal testing environments without fear of invalidating the results.


Tolerance of small animals to acceleration. Mice, rats, rabbits, finches, pigeons, and roosters were exposed to +Gz, minus Gz, and minus Gx inertial forces due to acceleration. The range of body weight of all animals was from 14 g to 1.6 kg. The magnitude of G and duration of exposure time were within 130 G and 20 min and the average rate of changes of G was 2.8 G/s. The G tolerances of these animals were compared with one another at 50% mortality. The tolerance of each species was expressed as the area under the tolerance curve. Changes of tolerance were obtained by the changes of direction of G force. The tolerance ratio of minus Gz to +Gz force was 0.58 and that of minus Gx to +Gz was 2.12. Body weight was inversely related to the threshold G-value at which animals are resistant to the prolonged acceleration.


Changes in serum and sweat magnesium levels during work in the heat. Serial changes in serum magnesium (Mg2+) were assessed in unacclimatized males during treadmill exercise in a hot (49 degrees/27 degrees C, dry/wet bulb) environment. Eight subjects walked at 5.6 km/h on a 0% grade, and at 90 min of exercise had a mean heart rate of increase of 70 plus or minus 5 (S.E.) beats/min, rise in rectal temperature of 2.1 degrees plus or minus 0.1 degrees C, and a weight loss of 2.07 plus or minus 0.10 kg. There was a significant (p less than 0.01) decrease in mean serum Mg2+ concentration (control: 1.87 plus or minus 0.06 mEq/I; 45 min: 1.81 plus or minus 0.07; 90 min: 1.72 plus or minus 0.08). The Mg2+ concentration in sweat samples collected over 90 min of work in the heat averaged 0.28 mEq/I (range 0.13 to 0.45). Thus, in normal man, exercise in an hot, dry environment resulted in a fall in serum magnesium which was not wholly explicable on the basis of sweat loss of this ion.


Variable venting valve for earmolds.

Variable venting valve for earmolds. The frequency response and loudness reduction characteristics of earmolds with variable venting valves (VVV) were investigated. Both side-branch and laterally vented earmolds were employed. Sound pressures were measured at 44 frequencies from 100 to 4 000 HZ in a modified HA-2 coupler with the VVV in four stages of opening: closed; 1/3 open; 2/3 open and 3/3 open. The effect of venting is primarily in the low frequencies. Little or no reduction in intensity is observed in the 'speech frequency' range and a modest amount is noted in the higher frequencies. The side-branch vented earmolds were more effective than the laterally vented earmolds. Calculated loudness reductions in phons were small. The effectiveness of the VVV, whether assessed by the frequency response or loudness reduction characteristics, is achieved within the first 1/3 of opening: further opening has little effect. The utility of the VVV, especially to the geriatric hearing aid user, is questionable.


Flight behaviour of pigeons in the weightless phase of parabolic flight. Pigeons were subjected to changes in G-loading during parabolic flight with special attention to their flight behaviour in the weightless periods. Experiments were performed 1) with the eyes covered, 2) with the legs tied to the body, 3) with eyes covered and legs tied, and 4) with none of these handicaps. In all these situations the flight behaviour of the birds was observed. Special attention was paid to the tumble-phenomenon, which appeared birds with covered eyes. The results are discussed and comparisons are made with the behaviour of man and fish under similar conditions.


Effect of noise exposure during primary flight training on the conventional and high-frequency hearing of student pilots. This investigation was part of a larger study conducted by Memphis State University. This laboratory's portion of the study focused on administering conventional audiometry (manual and self-recording), high-frequency audiometry (4 kHz-18 kHz), and a speech intelligibility test in noise to 108 Naval Aviation Officer Candidates prior to and following primary flight training in T-34 aircraft. Hearing protection consisted of either the APH-6C or APH-6D flight helmet. Cockpit noise levels in the T-34 range from 96-115 dBA; during cruise the noise level is approximately 100 dBA. Results indicate no significant change in hearing sensitivity or speech discrimination that could be attributed to noise exposure during primary flight training. Pre- and postprimary hearing levels obtained for the high frequencies compare favorably with high-frequency hearing levels obtained by Northern et al. (1968) for males in the age range 20-29 years. Questionnaire data indicated that a considerable number of the subjects had been exposed to potentially harzardous noise before entry into military service.


Reduced carbohydrate intake in the preparatory diet and the reliability of the oral glucose tolerance test. Two USAF flying populatins of 622 subjects each were subjected to the oral glucose tolerance test. One of these populations was prepared for the test by the ingestion of at least 300 grams per day (g/d) of dietary carbohydrate for the 3 d preceding the test; the other by 150 g/d of dietary carbohydrate. Statistical analysis of the data obtained from these populations revealed no change in the reliability of the oral glucose tolerance test as a diagnostic tool. Thaf school of Aerospace Medicine Consultation Service on all patients undergoing oral glucose tolerance tests.


Interpretation of an abnormal oral glucose tolerance test encountered during multiphasic laboratory screening. We have studied 162 healthy male flyers who had repeat glucose tolerance tests at intervals of 6 months to 2 years. On the premise that an abnormal oral glucose tolerance test (OGTT) was not reproducible because standard criteria were not strict enough, we evaluated 11 different criteria for diagnosing an abnormal OGTT. The number of abnormal tests varied according to the criteria but, no matter how the criteria were varied, the best reproducibility of any abnormal test on repeat testing was 50%. Factors affecting the reproducibility of an abnormal test are discussed. We conclude that a single, standard 2-h oral glucose tolerance test should be considered only as a screening test for diabetes mellitus, and that a final diagnosis of chemical diabetes mellitus should be made only if the carbohydrate in-tolerance consistently worsens or if insulin curves show hypofunction of the Islets of Langerhans. Our recommendations for followup studies of a patient with an initial abnormal OGTT are outlined. This study illustrates the importance of basic definitions of diagnostic criteria for diseases which have a long-term effect on the health of the flying population.


Proposal for improving ejection seats with respect to sitting comfort and ejection posture. It is generally accepted that in the case of ejection, the flexion posture is often the reason for vertebral body fracture, but to maintain the right egress posture (this means an erect or even hyperextended position) throughtout the entire duration of flight would increase pilot complaints about validly criticized misalignment of the seat profile. X-ray controlled seat studies led to the conclusion that an acceptable egress position does not allow relaxed sitting posture during normal cockpit activities over long periods. Therefore, an attempt at solution is being made by a seat device whose comfort is guaranteed by a back-rest construction variable at will. For emergency case, the posture will be optimized automatically and synchronically with the action of the power retraction unit. A schematic design outlines the construction.


Hearing and para-airport children.

Hearing and para-airport children. Audiometric screening was carried out on 3,322 elementary and high school students living in the vicinity of Logan International Airport, Boston, in an effort to determine whether noise from aircraft had any measurable effect on their hearing. Followup examinations and additional data on children failing the screening examination made it possible to classify the hearing losses as conductive, sensorineural, or mixed. The incidence of bilateral sensorineural or mixed hearing loss in the group living directly under flight paths or immediately adjacent to runways was not significantly different from the overall average. In normal subjects, the average sensorineural gap, a newly defined measure of high-tone loss, was not found to be significantly affected by the degree or duration of exposure to aircraft noise.


A longitudinal study of spatial ability. A number of studies have lent support to the sex-linked major gene theory of spatial ability. Expectations arising from this theory (although not necessarily unique to it) are that spatial ability can be measured in children, that it is the same as spatial ability in adults, and that an individual's position in a distribution of spatial ability remains unchanged over time. Results of a longitudinal experiment utilizing test scores of 76 high school students and their earliertest scores provide confirmatory evidence for these expectations.


A theoretical note on sex linkage and race differences in spatial visualization ability. Evidence on the poorer spatial visualization ability in various Negro populations compared to the white populations and on the direction and magnitude of sex difference in spatial ability relative to other abilities suggests the genetic hypothesis that spatial ability is enhanced by a sex-linked recessive gene and that, since the 20-30 percent admixture of Caucasian genes in American Negroes came mostly from male white ancestors, relatively fewer X-linked than autosomal Caucasian genes were transmitted to the American Negro gene pool. The genetic model as explicitly formulated indicates the kinds of data which could substantiate or disporve the theory, but which do not now exist.


Congenital adrenal hyperplasia I. Family studies of IQ. Thirty-one patients diagnosed as having congenital adrenal hyperplasia were given standardized IQ tests.  Patients' IQ was found not to be significantly higher than the IQ of nonaffected siblings or the expected IQ from parental values.  Thus the adrenogenital syndrome appears to confer no IQ advantage independent of family IQ level.


Congenital adrenal hyperplasia. II. Cognitive and behavioral studies. A sample of 31 patients with congenital adrenal hyperplasia was matched to a control group by sex, age, height, full-scale IQ score, and urban/rural site of residence. Patients and matched controls were tested on measures of masculinity and femininity and on sex-typed tests of cognitive ability. The two groups did not differ significantly on these measures. The finding is in disagreement with earlier reports of "masculinization" of behavior in female patients with congenital adrenal hyperplasia.


Photobehavioral differentiation in natural populations of Drosophila pseudoobscura and Drosophila persimilis. The photoresponses of natural populations of D. pseudoobscura and D. persimilis, occurring sympatrically, are measured in two environmental conditions ("at rest" and "disturbed"). Comparisons of the responses, intraspecifically and interspecifically, lead to the following conclusions. These must be considered within the confines of the operational nature of the measurement of laboratory photoresponses. (1) Within each species population, significant nonenvironmental differentiation has been allowed or produced by selection in the "at rest" photoresponse. No significant nonenvironmental differentiation is found in the photoresponse measured in a disturbed condition. (2) Within each species population, a higher mean "disturbed" photoresponse has been favored. The intensities or patterns of selection acting on these two photoresponses have differed such that more intrapopulation differentiation has been allowed or produced in the "at rest" photoresponse. (3) A higher mean photoresponse has been favored in D. persimilis for both conditions. The intensities or patterns of selection acting between these two species populations on the "at rest" photoresponse have differed such that more intrapopulation differentiation has been allowed or produced in D. persimilis. (4) Comparisons of this study with one on intraspecific and interspecific differentiation in wing length lead to the conclusion that the selective differences inferred above have acted at a level more specifically attuned to photobehavior.


Children's resemblance to their biological and adopting parents in two ethnic groups. This study tested the hypothesis that adopted children's individual IQs are more related to the individual social status ranks of their biological parents than to those of their adopting parents. Data from 20 Mexican-American and 21 white biological and adopting families in which the IQ score of the adopted child was available show that (1) there was no significant selective placement of these children in adopting homes, (2) there was no significant correlation between the midparent social-education rank of the adopting parents and their adopted children's IQ, and (3) there was a strong correlation between the midparent social-education rank of the biological parents and their children's individual intelligence ranks.


Relative mating activity of the sexes in homokaryotypes of Drosophila persimilis from a Redwoods population. Previous tests for mating activity of Drosophila persimilis homokaryotype KL (Klamath) and MD (Mendocino) chromosomal arrangements (northern California population: Redwoods) had shown KL to mate faster on the average than MD in homogamic tests. A strain (double-cross hybrid of four KL lines from the same population) with reliable high mating activity was developed for testing the sexes separately. Five pairs of KL-MD homokaryotype strains were chosen to be tested by the criterion that each pair had been derived from a separate wild KL/MD progenitor. Strains were crossed within arrangements in a diallelic design (20 inter- and five intrastrain crosses tested in 16 replicates per cross) to provide mating activity indices of four sets: KL females, KL males, MD females, MD males. Mating tests employed ten virgin experimental flies with ten tester (double-cross hybrid) flies of the opposite sex in 30-min observation periods. All flies were matured for 5 days at 25 degrees C before testing. Among parental strains, females were consistently higher in mating activity than males for both KL and MD arrangements. Most interstrain hybrids were heterotic, with KL and MD females not significantly different. However, hybrid MD males displayed greatest variation and had lowest mating activity, while KL males were the least variable and highest in mating activity. With heterosis in the hybrids, there was no predictability (additivity) from performance of parental strains to hybrid offspring. Mating activities of the two sexes were uncorrelated, indicating either that the sexes have independent genetic systems controlling mating activity or that the expression of the same genetic system is influenced by sex. Since the hybrid males of the two karyotypes displayed different courtship activity while the females were at about an equal level of receptivity, intrasexual selection among males is likely to be important in nature.


Response of Drosophila persimilis to phototactic and geotactic selection. The initial experimental population of Drosophila persimilis was photopositive and slightly geonegative. In this respect, the initial population of D. persimilis differed from the experimental population of D. pseudoobscura, described by others, which was close to photo- and geotactic neutrality. In D. persimilis as in D. pseudoobscura, photo- and geotactic selection was efficient in both positive and negative directions. In D. persimilis, unlike in D. pseudoobscura, the responses to geotactic and phototactic selection were clearly asymmetrical. As a result of such responses, selection practically eliminated interspecific difference in geotaxis and almost eliminated interspecific difference in phototaxis. The realized heritabilities of photo- and geotaxis over the first ten generations of selection in D. persimilis are between 6 and 7 percent. Practically, these heritabilities in D. persimilis have the same value, whereas in D. pseudoobscura the heritabilities are clearly different. These findings suggest that D. persimilis differs considerably from D. pseudoobscura in the composition of the genes determining photo- and geotactic behavior, most probably reflecting adaptations of these sibling species to different ecological niches. However, both species are capable of reacting quickly to external stresses by reorganizing their gene pools and by correspondingly changing their behavior.


Open-field activity in mice as a function of ceiling height:  A genotype-environment interaction. Three inbred strains of mice, C57BL/6, DAB/2, and BALB/c, were run in the standard McClearn-type open-field with l-, 1 5/8-, and 36-inch ceiling heights. Although all strains showed increased activity as a function of lowered ceiling height, an interaction between strain and ceiling height was obtained: while BALB/c mice were the least active strain in the 36-inch-ceiling-height field, they were the most active strain in the 1-inch condition. Implications of this strain times environment interaction for the well-established low open-field activity of BALB/c and other albino strains are discussed.


Sex-linked major-gene influences on selected types of spatial performance. Four paper-and-pencil spatial tests, measuring two- and three-dimesional spatial visualization and spatial orientation, were administered to 2508 Caucasian high-school students. Sibling correlations and within-sex score distributions were examined for the influence of a major sex-linked gene. Sex-linked influences were most clear on the test of two-dimensional visualization and on an average of the standard scores on all the tests. For those tests best fitting the genetic model, estimates of the frequency of the recessive gene (contributing to good performance) we-re near 0.45. There was evidence of incomplete dominance in females. Environmental or non-sex-linked genetic factors influenced spatial performance but did not systematically improve performance with age.


Alteration of the rabbit aorta following feeding of cholesterol diet in combination with sheathing of aortic segments by polyethylen tubes. Nutritional disturbance and blockage of drainage of the vascular wall which were considered to play an impoetant role in the pathogenesis of arteriosclerosis were experimentally produced by aortic sheathing previously (Huth et al., 1974).  Alteration of the rabbit aorta following feeding of cholesterol diet in combination with sheathing of aortic segments by polyethylen tubes is reported in this paper.  The results were as follows: 1. When rabbtis were fed a cholesterol diet, atherosclerotic lesions formed in the intima of the aorta.  2. When rabbits were fed a cholesterol diet with simultaneous aortic sheathing, aortic atherosclerosis was also produced within the sheathed segments.  3. When rabbits were fed a cholesterol diet after formation of intimal thickenings within the sheathed segments, lipid deposition was scarce within these segments.  The results suggest that among the pathogenetic factors of atherosclerosis a disturbance of vascular nutrition and a blockage of vascular drainage may be of greater importance than hypercholesterolemia.


[Morphological effects of intraperitoneal oily fatty acids on the intestine and peritoneum of rats]. Changes of the mucosa of the small intestine in animal experiments can be produced by a variety of methods. The direct application of numerous chemical agents on the epithelium of the mucosa and parenteral administration of cytostatics as well as an indirect damage by experimental intestinal lymphatic obstruction lead to mucosal lesions with atrophy of the villi. Our paper presents a simple indirect method for induction of structural mucosa changes in rats using experimentally produced peritoneal alterations as a precursor. The first experimental group with 108 male wistar rats was divided into 5 subgroups and treated as follows: 43 rats got continuous daily intraperitoneal injections of 3-3 ml/kg body weight sesame oil DAB 6 which contains 50% oleic acid, 36% linolic acid, 1% free fatty acids, 0.1% lecithin and portions of stearic, palmitic and arachic acid; 6 rats got 6.6 ml sesame oil per kg i.p., 43 animals received daily doses of 3-3 ml oil/kg per orally by a pharyngeal tube, 6 rats of each group were sacrificed after 68 and 92 days, all the rest were killed after 100 days of continuous daily treatment. Aortic blood was used for determination of the total cholesterol serum concentration. Blocks of tissue of every organ were fixed in 4% formalin, sections were stained with hematoxylin and eosin, hematoxylin-sudan and by the periodic acid Schiff (PAS-) method. For the purpose of autoradiographic determination of the 3H-thymidine labelling index the rats were administered i.p. 2 mCi 3H-thymidine/kg 40 minutes prior to death. Autoradiographs were prepared from sections of the small intestine by using liquid photoemulsion Ilford K5. In the second experimental group 7 rats got a single i.p. injection of 5 ml, 5 rats of the 10 ml and 9 rats of 20 ml sesame oil per animal; 4 rats were administered 8 ml daily for 5 days...


Effects of maternal hypoxia on incorporation of 3-H-thymidine into DNA of neural tube matrix cells in the mouse embryo (an autoradiographic study). The effect of maternal hypoxia on DNA synthesis of neural tube matrix cells has been studied in the ten-day old mouse embryo.  The experiments were carried out by means of the autoradiographic technique.  The relative uptake of 3-H-thymidine into nuclear DNA was determined by means of the silver grain count present in the nuclei and of the labeling index of neural tube matrix cells in the telencephalon of normal and hypoxia-exposed mouse embryo on the 10th day of gestation.  The results are summarized as follows; 1. The thymidine incorporation and labeling index were noticeably reduced under maternal hypoxia of 6 percent O2 for 1 hour.  When 3-H-thymidine was injected immediately following hypoxia for 6 hours, matrix cells showed almost normal thymidine uptake and labeling index.  However, when thymidine was injected 2 hours after the same hypoxia, the matrix cells showed a definite reduction of thymidine incorporation and also of labeling index.  There were regional differences in reduction of nuclear DNA synthesis throughout the cerebral structure, and it was most marked in the telencephalon in this developmental stage.  The matrix cells in the di-, mes- and metencephalon appeared less or not at all affected by maternal hypoxia.  2. In mouse embryo exposed to hypoxia of 6 percent O2 for 6 hours on the 7th day of gestation and sacrificed 1 hour after thymidine injection on the 10th day, matrix cells showed a marked reduction of grain count and an increase of labeling index.  The effect was larger than that seen on the 8th or 9th day of gestation.  3. Qualitative examination revealed focal loss of 3-H-thymidine label around pyknotic nuclei in the neural tube of some of the embryos after hypoxia of 6 percent O2 for 6 hours.  4. The significance of the disturbance of DNA synthesis of embryonic neural tube cells by maternal hypoxia was briefly discussed in relation to teratogenesis.


[Pathogenesis of Wallenberg's syndrome]. In 1895 Wallenberg described a syndrome characterized by neurological symptoms produced by unilateral softening of the dorsolateral medulla oblongata. In the majority of cases the softening was caused by an arteriosclerotic-thrombotic occlusion of the homolateral intracranial vertebral artery or posterior inferior cerebellar artery, respectively. Occasionally an occlusion of the basilar artery or of the distal extracranial vertebral artery was responsible. In contradiction to the original thesis of Wallenberg, an embolic arterial occlusion could rarely be diagnosed. In particular cases the syndrome was caused by syphilitic vascular changes, tumors, metastases or encephalitis in the region of the dorsolateral medulla oblongata. This paper describes two cases of Wallenberg's syndrome. In the first case (70-year-old-male) the softening of the dorsolateral medulla oblongata was caused by occlusive thrombosis of the homolateral posterior inferior cerebellar artery with concomitant severe arteriosclerosis of the extracerebral brain arteries. The latter variation is characteristic for hypertensive vascular diseases. Thus Wallenberg's syndrome must be classified in similar cases as a complication of hypertensive peripheral cerebral arteriosclerosis. The second observation refers to a 51-year-old-male with bronchiectasis and chronic bronchitis. Metastatic encephalitis was found in several parts of the mid-brain, including the medulla oblongata. The dorsolateral medulla oblongata was destroyed by septic softenings (pneumococci). In this case, however, arteriosclerotic stenosis or thrombosis of the cerebral arteries could not be found. According to the literature metastatic encephalitis, as described in the last case, is an extremely rare cause of Wallenberg's syndrome.


Ballistocardiographic and electrocardiographic changes in men working with lead. Early ECG and Bcg changes in workers exposed to lead have been described. The changes are a consequence of disturbed myocardial metabolism, momentary coronary spasms and neurovegatative dystonia.


Kinetics of the left and right heart ventricles revealed by precardial cardiography as manifestations of compensatory reaction in myocardial infarction. A comparative study of the function of the left hand and right ventricles in different myocardial infarction periods was carried out in 100 patients. The principal method used for specific analysis of the phase structure in the function of the left and right ventricles was that of precardial cardiography. The data obtained indicate that in the acute infarction stage both ventricles function hypodynamically. Later, some asynchronism in the restoration of the affected contractile function of both ventricles is observed. The study of the kinetics of the left and right heart ventricles enables one to evaluate the markedness of the compensatory processes and some of their mechanisms.


Ballistocardiographic changes after carbon dioxide baths. Ballistocardiography was used for following up the changes in cardiovascular dynamics in 2 groups of patients suffering from hypertensive disease stage II. In a group of hypertensive patients who took CO2 baths for 28 days, or improvement of the pathologically altered Bcg showed with a simultaneous decrease in blood pressure and pulse rate for a better dynamics of the cardiac function. In the group of hypertensive patients taking isothermic tap-water baths under identical conditions, the same trend in the Bcg changes was found, but these changes were not statistically significant.


Ballistocardiography in sanatorial and health resort rehabilitation of patients after myocardial infarction. A sanatorial and health resort rehabilitation was carried out in patients after myocardial infarction. The rehabilitation program included exercise therapy and carbonic acid baths. The ballistocardiographic studies conducted with a diagnostic purpose indicate that carbonic acid balneotherapy may be used in patients after the third month following the onset of myocardial infarction. Clinico-physiological investigations indicate that ballistocardiography may serve to control the effectiveness of sanatorial and health resort rehabilitation and to determine the mechanism of action of the physical factors involved.


Hemodynamic syndromes in apex-cardiography. The results from 8,000 investigations and comparative studies between mean and systolic pressures in the left atrium and changes in the diastole portion of the apex-cardiogram are presented. A correlation is established between the mean pressure and OF duration for post-puberty ages. A similar dependence is also found between the amplitude value of the atrial wave and the systolic pressure in the left atrium. The physiological variations are outlined. Three distinct, pathological hemodynamic syndromes, expressing the dependence between the magnitudes of systolic and mean pressures, are established.


Apex-cardiographic approaches applicable to incipient myocardial failure in preclinical periods. A survey is made of present-day methods proving myocardial failure, and a new indirect method is set forth based on apex-cardiography. After consideration of the physiological variations of the 'a' wave and OF interval, they are checked in an after-exercise state. It is established that the slow normalization of 'a' wave, which follows the restoration of the pulse rate initial values, is an indication of incipient myocardial failure. This regularity is observed for all diseases involving some failure of the myocardial functions.


Evaluation of cardiac pump performance and heart muscle mechanics from the apex cardiogramm. Theoretical considerations. Theoretical grounds are outlined for assessing the pump action of the heart and myocardial mechanics, respectively, in terms of ACG displacement ventricular function curve and displacement percentage amplitude-rate of ascent curve. These displacement relationship curves compare the a% of the ACG with the ACG-derived stroke volume, on the one hand, and the isovolumetric percentage amplitudes with the rate of ascent of the slope, on the other. They indicate the expected direction changes in the ventricular function and in the force-velocity relation curves.


The value of quantitative apex-cardiography as compared to intracardiac functional diagnostics of the left ventricle. A quantitative procedure of recording the apex impulse as regards its duration, force and rate of development of force requires a DC amplification ensured by a semiconductor strain-gauge transducer. In addition, impact and diameter or stamp and internal diameter of the contact ring must be defined. Comparative measurements show a good correlation between timing, absolute values and the first derivatives.


Apex cardiographic evaluation of the velocity of contractile element shortening at aortic valve opening (ACG-VCE-E). The average values of the velocity of contractile element shortening at opening of the aortic valve, assessed apex-cardiographically in 100 normal subjects and in 63 patients with previous myocardial infarction were 0.60 and 0.53; with correction for preload and values became 0.11 and 0.049 (psmaller than 0.0000006). It is concluded that the proposed concept of expressing myocardial mechanics in terms of displacement curves and indices approaches the problem clinically in a safe way.


Use of ballistocardiography for determining the hyperfunction of the left ventricle. A study of patients with patent ductus arteriosus and atrium septum defect, by use ofdirect body Bcg showed that an increased IJ amplitude is due to an increased stroke volume of the left and not of the right ventricle. High IJ amplitude is observed in patients with cardiovascular diseases, causing an increased output of the left ventricle ofover 50% above normal.


On the total relaxation of the left ventricle in primary rheumocarditis in children. Apex-cardiographic studies. Apexcardiographic studies were carried out on 100 healthy children and 120 children, aged 3-14 years, with primary rheumocarditis. An analysis of the results indicate that the duration of total relaxation of the left ventricle is prolonged in the group of children suffering from primary rheumocarditis. The prolongation of TR is due to the increased PD interval, as well as to the prolonged IVR. The changes described lead to a certain phasic delay of the aortal and opening of the mitral valves.


Quantitative analysis of the carotid sphygmogram in atherosclerosis. A study has been made, by means of quantitative analysis, of the changes in the CSG of 355 persons-131 healthy, 112 with ischemic heart disease and 112 with hypertension. The quantitative analysis includes: (1) coefficient of declination, pointing to the declivity of the anacrotic limb; (2) coefficient of propulsion, pointing to the time of formation of the maximum peak and (3) level of indentation, pointing to the height of the valve notch. These 3 indices regularly increase along with progressive induration of the arterial wall and serve as quantitative criteria for a more accurate differentiation of the separate types of CSG used in clinical practice.


The relation between aortic elasticity and systolic complex of the direct body ballistocardiogram. On the basis of the analysis of 60 clinically healthy men divided into 2 age groups according to the degree of aortic elasticity, it was found that the diminution of elasticity was accompanied by reduction of the amplitude of I, J and K waves, increase of the gamma-index (gamma=aK/aJ) and shortening of the H-K interval. The subjects were divided into analysed groups according to the cardiographic indices of atheromatosis and their age. Similar types of change, especially for the decrease of I, J and K wave amplitudes, can be an effect of the diminution of cardiac contractility. Consequently, the correct evaluation of a pathologic Bcg (especially in older people) requires additional information as to the condition of aortic elasticity.


Changes in the ballistocardiogram in pulmonary hypertension. A comparison of Bcg changes was made between a group of healthy individuals, a group of pneumopaths with normal blood pressure in the pulmonary artery at rest and another group of pneumopaths with pulmonary hypertension at rest. The tension in the pulmonary artery was measured by venous catheterization. It was found that: (1) the H wave of the Bcg was significantly higher in both groups of pneumopaths than in the group of healthy individuals, and (2) the L wave was significantly higher in pneumopathics with pulmonary hypertension at rest than in pneumopaths with pulmonary normotension and healthy individuals.


Ballistocardiogram studies compared with an analysis of the left-ventricular systole in patients with stage II hypertension. Studies were made on Bcg changes in 46 patients suffering from hypertensive disease stage II. These were compared to the phase changes in the systole of the left ventricle. It was established that more substantial phase changes in the systole of the left ventricle corresponded to a higher degree of changes in the Bcg. Emphasis is laid on the significance of complex cardiographic investigations in patients with hypertensive disease, as a comparatively easily accessible method for evaluating the mechanics of contractility of the  myocardium. The method is a useful addition to the overall clinical picture of the disease.


Rheographic estimation of peripheral diabetic angiopathy. Longitudinal rheography was used for investigation of 294 diabetics and 176 healthy controls aged 3-82 years. It was found that the vascular lesions in the lower extremities in diabetics are bilaterally similar, and that they are 3-14 times more frequent in comparison with nondiabetic controls. Whereas the diabetics are certainly threatened by severe vascular obliteration with advanced age, the same is not necessary for the nondiabetics. Lighter vascular lesions were found even in diabetic children under 5 years of age. A conclusion is reached that rheography is a reliable method for investigation of vascular lesions in diabetic patients.


Age-dependent changes in the complex of impedance plethysmographic and hemodynamic indices of the lung and aorta. The author has tested 2 groups, each consisting of 30 healthy individuals aged 21-40 and 41-60 years, respectively, by means of IPG records of the lung and aorta. The LIPG has not shown any essential changes with the advance in age, wherease the AIPG showed a decrease of the Q-a interval, as well as the Vmaxt of quick blood filling and of the rheographic systolic index without morphological changes.


Changes in the asynchronous contraction of the left ventricle in primary rheumocarditis in children. An attempt has been made at studying in greater detail the changes in the AC of the left ventricle in primary rheumocarditis. The changes, evaluated with the help of an ACG, have been differentiated from such in the EMI and those in IVC. The studies werecarried out on 220 children, aged 3-14, divided into 2 groups: 100 healthy controls and 120 with primary rheumocarditis. An analysis of the results shows that the rheumatic process in the myocardium modifies the normal transformation of electrical events into mechanical ones, and prolongs the AC phase. The latter is due to the increase of EMI duration. IVC is practically unchanged. The prolonged duration of EMI may be connected with a certain compensatory reaction.


Correlation between the duration of the cardiac cycle and the complex of impedance plethysmographic hemodynamic indices of the lung and aorta. Rheographic studies of the lung and aorta have been performed on 20 patients with atrial fibrillation and on 30 normal individuals before and after Valsalva's manoever. The findings disclose a strongly expressed positive correlation between the duration of the cardiac cycle and the rheographic systolic index, a Vmax., a Vm and a negative correlation with the Q-a interval and the ab/RR of the lung and the aorta.


High-frequency (acceleration) direct body ballistocardiography. Representation of the carotid pulse, phono- and apex-cardiogram in the Bcg. The carotid pulse PCG, ACG and Bcg appear to represent the same basic dynamic expression whether of atrial or ventricular origin. The early isometric and ejection waves are comparably delineated. The points of A2, P2 and S3 can be detected, particularly,in CP2, ACG2 and df-Bcg. The gain, thereby, in the significance of the Bcg is encouraging.


Simulation of catecholamine action in an improved electrical model. A further development of an electrical model of circulation is presented. The progress consists in: (1) the ventricles are represented as a changing capacity; (2) a constant amount of charge is re-circulating in the system; (3) the contractility of the heart can be varied; (4) the valves are represented by relays, and (5) the pulse wave velocity can be represented. Catecholamine action is studied by changing the heart rate, contractility, elastic resistance and peripheral resistance; the influence on systolic, diastolic pulse pressure and flow pulse in different parts of the arterial system is measured. In the discussion the importance of the concept of deformation-capacity-internal surface of the ventricles for the understanding of the cardiovascular system as a unity is stressed.


The role of kinetocardiography in the complex study of the mechanical cardiac activity in ischemic heart disease. The complex study of mechanical manifestations of cardiac activity by kinetocardiography, along with a complete clinical examination, is suggested as a rather sensitive method which precisely detects the changes of cardiodynamics in disturbances of the coronary circulation, rendering information useful in diagnosis and prognosis.


Technical principles of spectral- and vectorkinetocardiography. The use of calibrated spectral, narrow-band spectral abd vectorkinetocardiography is suggested for clinical practice. Dependence of the KCG frequency characteristics and vector orientation on the functional state of the myocardium was established. The numerical characteristics of spectral kinetocardiographic data proved to be fit for use during treatment. They provide for a more objective estimation of the mechanical cardiac activity including machine-data processing.


A portable ballistocardiograph.

A portable ballistocardiograph. The instrument consists of a pneumatic accelerometer which is worn on the top of the head, secured by a strap under the chin. It is connected by a tube to a sensitive capacitance manometer, the signals from which are amplified and displayed on a meter. Connection can also be made to an ECG recorder to display waveform. The apparatus is battery-operated and fully portable, so that it is possible to record Bcg on patients in their own beds.


Semiautomatic-planimetric analysis of the BCG (by means of an electrointegrationset). The present invention is based on the use of two ballistic galvanometers in connection with an ECG-Bcg set, making it unnecessary to change poles mechanically each time in order to take in surface values above and below the zero line. A further advantage is that surface portions above and below can be dealt with simultaneously, i.e. with the same surface and without having to wait for the subsequent one(s), which already could have changed. The indicated values of the ballistic galvanometer can, on the one hand, be read directLy or, on the other hand, be documented mechanically by means of a film camera or by a photographic camera with or without different adjustable time delays or by electronic coupling after applying the measurement(s).


The calibration of stethoscopes and phonocardiographic microphones. The response of stethoscopes and chest microphones depends on the impedance of the sound source, which must therefore have the same impedance as the body, and must emit a signal related to the sound intensity in the body when no instrument is applied. Body impedance depends on the geometry of the instrument and on the force of application, etc. The source impedance must, therefore, be variable to suit test conditions. Unexplained discrepancies in published impedance measurements hinder standardisation of source impedance. The impedance of an electromagnetic vibrator can be modified electronically to meet these requirements.


A comparison between noninvasive and bloody methods for use in the continuous estimation of cardiac contractility. Simultaneous measurements of the blood pressure in arteria carotis with a catheter device and a new noninvasive continuously recording method were carried out in 7 rabbits with a chronically isolated arteria carotis loop. Results show good correspondence between both methods for pulse curve and blood pressure over a long period and a wide range,as well as good reproducibility. An absolute calibration for the noninvasive method is impossible. The new method is quite suitable for studying the dynamics of pressure pulse and pressure behavior.


The ballistocardiogram in myocardial infarction. ECG and Bcg studies have been carried out on 40 youths, aged 18-23, suffering from mycoplasmic pneumonia; in 19 of them mild Bcg changes were established. The frequencyof ECG changes is less-12 patients. The pathological deflections in Ecg and Bcg in all patients normalize before the control examination, which takes place 30 days after discharge of the patients from hospital.


Cardiac lesions caused by mycoplasmic pneumonia in youths according to ballistocardiographic and electrocardiographic data. ECG and Bcg studies have been carried out on 40 youths, aged 18-23, suffering from mycoplasmic pneumonia; in 19 of them mild Bcg changes were established. The frequency of ECG changes is less - 12 patients. The pathological deflections in Ecg and Bcg in all patients normalize before the control examination, which takes place 30 days after discharge of the patients from hospital.


Echographic detection and localization of BB shots in the eye and orbit. BB shots and other spherical foreign bodies produce long chains of rapidly successive echo spikes which gradually decrease in height. These patterns are specific for this type of foreign bodies and allow their reliable detection and accurate localization. A-scan echography has become a very useful addition to X-ray examination in order to determine whether such foreign bodies are intra- or extraocular. Echography also helps to localize such foreign bodies during surgery and to evaluate the posterior segment of the eye in the presence of opaque ocular media (hemorrhages, cataract). Although it is sometimes possible to demonstrate specific B-scan patterns of spherical foreign bodies, A-scan echography is the method of choice since it is faster, more reliable and more accurate.


Ocular tumor patterns.

Ocular tumor patterns. The use of choroidal excavation and vascular pulsations in the ultrasonic diagnosis of tumors has been a helpful diagnostic feature. Evaluation of choroidal tumors is presently performed with A-, B- and M-scan techniques. Solid tumors of high homogeneity produce characteristic hollows or acoustic quiet zones that replace the normal choroidal pattern. M-scan patterns of vascular pulsations are also useful in demonstrating vascularity or choroidal tumors. Color displays accentuate amplitude variations in ocular tumors.


Relation between histological structure and ultrasonogram in malignant melanoblastoma of the choroid. The extreme polymorphy of the histological structure of the malignant melanoblastoma of the choroid, and the diverse forms of the tumor echogram stimulated the comparative investigation of such tumors in 22 cases. The complicated combination of different histological details cannot be revealed through clinical echo-ophthalmography. However, connections between the histological preparation and the interference picture can be demonstrated subsequently.


Cavernous hemangioma of the orbit. A differential diagnosis in clinical echography. Cavernous hemangiomas of the orbit produce echographic A-scan patterns which allow their detection, localization, measurement, and differentiation from all other orbital lesions with a high degree of accuracy. Specific echograms, however, of these tumors can only be obtained with optimized and standardized A-scan instruments providing specific settings of the sensitivity, amplifier characteristics, dynamic range, expansion of the screen display, filtering, etc. When instruments other than these are used, both differentiation and detection of this tumor become difficult or impossible. The more an A-scan instrument differs from the optimized and standardized type, the less successful the diagnosis of cavernous hemangiomas becomes, B-scan techniques add to the A-scan examination by better demonstrating the round shape and the topographic relationship to the globe, the optic nerve and the orbital wall.


A determination of the velocity of ultrasound in cataractous lenses. The velocity of sound determinations made in this study are the result of measurements accurate to 0.5 m/sec. The velocity of sound in a series of 50 cataractous lenses was found to be an average of 1,629 m/sec, 11 m/sec slower than that of normal adult lenses. The velocity of sound found in a smaller series of child lenses was 1,659 m/sec, 30 m/sec faster than the cataractous adult lens. It is postulated that this represents a trend of decreasing velocity of sound in the lens with increasing age.


Methodical and clinical aspects of the echo-oculography. The pros and cons of the various B-scan modes are discussed, and the preferences of the combination of the linear scan and the arc scan is eludicated with experimental results. Some techniques of modulation of the intensity of the B-scan oscilloscope are compared, the starting point being an A-scan equipment with a logarithmic gain amplifier. It is concluded that either a differentiated video signal, or a system employing standard pulses are differentiation of the video signal, or a system employing standard pulses after differentiation of the video signal enhances the anatomical outlining of the B-scan pictures. In order to provide quantitative information of the echo-pattern, A-scan pictures have to be made. These pictures are taken at positions with the B-scan display.


Comparative ultrasound oculometry. TAU-measurements of thirty eyes with three standard equipments. Ultrasound oculometry (A mode) was performed in 30 eyes with three different standard equipments and great effort was made to make the three sets of measurements comparable. In spite of careful calibration procedures significant inter-equipment differences were found: anterior chamber depths and lens thicknesses showed the greatest discrepancies. These findings should be kept in mind when oculometric results of different authors are compared. A standardized eye-like phantom is desirable as a common reference for all who work in ultrasonic oculometry.


Ten-year study on clinical echography in intraocular disease. During the past 10 years, clinical echography has been developed to a valuable and even indispensable examination method with which more than 25 various conditions and diseases or groups of lesions within the globe can be differentiated (the majority of them with a high degree of realiability and accuracy). Two signigicant steps to this end were the optimizing of both instrumentation and examination techniques as well as the standardization of the A-scan method. A few of the major conditions and diseases of the posterior segment of the globe, e.g. retinal detachments and retinoblastomas, are discussed in detail in this study, while ocular foreign bodies, malignant melanomas and other choroidal tumors and pseudo-tumors are discussed in two other studies presented in these proceedings (see pp. 109,141). At the end of this 10-year period, clinical echography, although quite mature, is still a very young examination method which can and will be further improved to an even more reliable and at the same time easier technique. Both A-and B-scan techniques are important for the diagnosis of intraocular diseases: the (standardized) A-scan method for a reliable detection as well as quantitative and kinetic evaluation, the B-scan technique for a better demonstration of the shape and topographic relationship of lesions in the vitreous and at the posterior pole.


Retinoschisis and retinal detachment, an ultrasonic comparison. The ultrasonic appearance of retinoschisis is a single echo similar to, but of smaller amplitude than that of retinal detachment and separated from the scleral echo by a silent space representing subretinal fluid . Quantitative ultrasonic measurements were made in a series of patients and show a statistically significant difference between the acoustic reflectivities of the separated retina in retinoschisis and retinal detachment.


Clinical ultrasonography of intraocular foreign bodies. 92 eyes have been examined with A-scan ultrasonography (8 MHz, Kretz-Technik apparatus 7100 MA and 7200 MA). Ultrasonic location of nonmagnetic and magnetic foreign bodies is compared to Comberg's radiographs and to intraoperative methods usch as stereoradioscopy or transillumination with the glass fiber diaphanoscope. Definitely corresponding results have been obtained in 60 cases. Ultrasonic location was difficult with small foreign bodies (reflecting surface less than 2 mm-2) within the orbit, the sclera, or within less than 2 mm from the sclera, as well as in severe vitreous clouding. Such cases should be evaluated with all location procedures available before considering further management.


Role of early synovectomy of the knee joint in rheumatoid arthritis. The prospective study of 32 knees in 26 patients with rheumatoid arthritis was carried out with an average followup of 3 years. Relief of pain and control of inflammation locally were obtained in 22 of 32 knees (69%). Articular cartilage was preserved in 20 of 28 knees (71%) and the synovitis recurred in 9 knees (28%), 7 of which showed progressive loss of cartilage. Therefore, it appears that synovectomy, if performed at a stage in which articular cartilage is still normal and after medical therapy has failed, is a very effective method for preserving articular cartilage and controlling inflammation locally. However, with a longer followup the disease with loss of articular cartilage will recur in a large number of cases. In patients whose disease progresses rapidly, no form of therapy effectively controls joint destruction.


Metastatic adenocarcinoma of synovium presenting as an acute arthritis. Diagnosis by closed synovial biopsy. An acute arthritis may accompany the onset of cancer. A case of metastatic adenocarcinoma of the synovium presenting as an acute arthritis is described. The diagnostic importance of a careful synovial fluid analysis and the use of closed synovial biopsy are emphasized.


Extensive phalangeal cystic lesions: sarcoidosis limited to the hands and feet? A young black man is presented with a 33-month course of insidious but eventually striking hand deformity and limitation of motion in the absence of any other symptoms. Radiologic and histologic findings of the digits support the diagnosis of sarcoidosis, though physical, laboratory, and chest x-ray examination show no evidence of this multisystem disease.


Influence of cyclophosphamide and other immunosuppressive drugs on immune disorders and neoplasia in NZB/NZW mice. NZB/NZW mice were treated with various immunosuppressive drugs used in human SLE. Cyclophosphamide (5 mg/kg 6 days out of 7), alone or with prednisolone, was better than azathioprine, prednisolone, or azathioprine-plus-prednisolone, in prolonging survival and/or reducing proteinuria, Coomb's antibodies, antinuclear antibodies, and glomerular deposits of gamma-globulin. Intermittent bolus therapy with cyclophosphamide (59 mg/kg/10 days) was as effective as daily therapy. However, 61% of the mice receiving any cyclophosphamide regimen developed malignant tumors compared to none in the other groups.


Efficacy of lithium in rheumatoid arthritis with granulocytopenia (felty's syndrome). A preliminary report. Lithium carbonate was given orally for 6 weeks in varying doses to 10 patients with Felty's syndrome. All patients receiving 900 mg of lithium daily showed statistically significant elevations in granulocyte count during therapy. The effect was usually noted within a week and did not persist when the drug was withdrawn. The percentage increase in mean absolute granulocyte count varied between 138% and 617% of control value in different patients; the lower values were observed in those patients with basal serum lithium concentrations less than 0.5 mEq/liter. It is concluded that a consistent rise in peripheral blood granulocytes was achieved by lithium carbonate in a dosage of 900 mg daily in patients with Felty's syndrome.


Effects of acute cartilaginous injury on serum and cartilage lysozyme levels. Acute cartilage degradation was produced in rabbits by the intravenous injection of crude papain. This resulted in a significant rise in serum lysozyme in 97% of the animals, as well as a fall in the residual lysozyme content of auricular and costal cartilage. The rise in serum lysozyme paralleled the rise in serum chondroitin sulfate. The source of the rise in lysozyme appeared to be the release of extracellular, nonlysosomal lysozyme from the cartilage matrix. Serum lysozyme elevation in arthritic disorders may reflect cartilage degradation.


The hyperviscosity syndrome in rheumatoid arthritis due to intermediate complexes formed by self-association of IgG-rheumatoid factors. Three patients with rheumatoid arthritis and abundant circulating intermediate complexes were studied. Two of these patients presented with the hyperviscosity syndrome. All 3 patients had markedly elevated plasma and blood viscosity, and the intermediate complexes were thought to be responsible for the increased viscosity. Studies on the isolated intermediate complexes revealed that they were formed by self-association of IgG-rheumatoid factors.


Aortic endothelial mitosis and Evans blue uptake in cholesterol-fed subscorbutic guinea-pigs. Groups of ovalbumin sensitised, subscorbutic guinea-pigs were subjected to various regimens for 8-10 weeks. Group 1 were given 0.25 mg/100 g body wt. cholesterol by mouth daily and were stressed with intraperitoneal injections of ovalbumin twice weekly. Group 2 received the cholesterol only and Group 3 were stressed only. Group 4 on the low vitamin C diet only acted as controls. Evans blue uptake tests and tritiated thymidine autoradiographs of Häutchen preparations of aortic endothelium were made on each animal. Endothelial mitosis was greatest in those areas of the aorta that had taken up the Evans blue most avidly. This was most apparent in Group 1, though to a lesser extent in Groups 2 and 3 also. Group 4 showed no dye uptake and the mitotic index was not raised. Blood ascorbic acid and plasma cholesterol levels are given for the various groups.


Influence of dietary fats on atherosclerosis, coagulation and platelet phospholipids in rabbits. Male rabbits were fed for six months diets comprising cholesterol (0.1%) and either butter alone (10%) or butter (5%) plus cacao butter, coconut oil, olive oil, or corn oil (4.5%). These fats could be classified according to their atherogenicity as follows, in decreasing order: butter, olive oil, coconut oil, cacao butter, and corn oil. The severity of the atherosclerotic lesions was correlated with the plasma cholesterol. By contrast, concerning their effect on the recalcification plasma (platelet-rich) clotting time (PCT), These fats could be classified in the following way: cacao butter, butter,, coconut oil, olive oil and corn oil. The values of the PCT were significantly correlated with the ratio stearic/linoleic acid in the dietary fats, the clotting activity and the fatty acid composition of the platelet phospholipid fractions examined (phosphatidyl serine plus phosphatidyl inositol), but not with the concentration of these fractions in platelets. Butter was the only fat able to induce severe alterations at the same time in coagulation (presumably through an increase in the activity of certain platelet phospholipids), lipemia and arterial wall morphology.


Effect of the essential oils of garlic and onion on alimentary hyperlipemia. The effect of garlic and onion on alimentary hyperlipemia, induced by feeding 100 g butter, has been studied in 10 healthy subjects. The freshly extracted juice of 50 g of garlic or onion, as well as an equivalent amount of their ether-extracted essential oils, was administered randomly on four different days during a one-week period. Garlic and onion have a significant protective action against fat-induced increases in serum cholesterol and plasma fibrinogen and decreases in coagulation time and fibrinolytic activity. The essential oil fraction, which contains all the taste and odour, exactly duplicated the beneficial effects of whole garlic and onion. It is, therefore, concluded that the active principle of garlic and onion is the essential oil, which chemically is a combination of sulphur-containing compounds, mainly allyl propyl disulphide and diallyl disulphide.


Relationship of raised atherosclerotic lesions to fatty streaks in 19 location-race groups. Atherosclerosis was graded by gross inspection of Sudan-stained arterial intimal surfaces estimating percent surface involved by raised lesions (R), fatty streaks (F), and no lesions (N). The right coronary artery and abdominal aorta of over 20,000 cases, 25-69 years of age, from 19 location-race groups were used. Cases were classed by sex, broad cause of death categories, and age. Raised lesions expressed as a percentage of all types of lesions was found at each age to have approximately a constant ratio to the percentage surface involved with all types of lesions. This was true over the range of surface involvement within age, sex, and cause of death classes, but between classes the ratio was not constant. Comparisons among location-race groups indicated marked differences in mean involvement by all types of lesions and by raised lesions expressed as a percentage of all lesions. The variation among groups in the fraction of raised among lesions was found to be partly related to parallel variability in average involvement by all types of lesions. However, some groups stood out as having too much or too little of raised lesions for their degree of involvement by all types of lesions. For instance Manila had extensive raised lesions with little fatty streaking while Bogota had more fatty streaking but not so much of raised lesions. In the sequence N yields F yields R, Class A causes act at both stages of atherogenesis while Class B causes act at stage I or stage II but not both. Class A and Class B causes both revealed important variation among location-race, sex, and cause of death groups.


Arteriosclerosis in the African elephant: Part 2. Medial sclerosis. A type of spontaneous arteriosclerosis, described as medial sclerosis and quite distinct from atherosclerosis, was found in the aortas, coronary arteries and aortic branch arteries of free-living elephants (Loxodonta africana) in Uganda and Kenya. The lesions took the form of calcified fibrotic plaques in the inner tunica media. The calcification appeared to commence in the internal elastic lamina and was associated with atrophy of medial smooth muscle fibres and their replacement by fibrous tissue. In the aorta, medial sclerosis was found to be associated with aortic dilatation, decreased wall thickness and decreased extensibility. These changes were shown to result in substantial increases in the tangential stresses carried by the tissues of the aorta and coronary arteries. As with atherosclerosis, medial sclerosis increased progressively with age; and the approximate involvement of the aorta at different ages could be predicted from linear regression equations. There was no difference in the severity of lesions between male and female animals. Biochemically, the lesions of medial sclerosis were associated with decreased amounts of elastin and increased amounts of collagen in arterial walls. Arterial tissue showing medial calcification always contained less than 30% elastin by weight. In addition, the severity of medial sclerosis in individual elephants was found to be positively correlated with the concentration of calcium in their sera. The pathogenesis of these lesions is discussed and it is suggested that mechanical stress, medial anoxia and high serum calcium levels all contribute to the aetiology of medial sclerosis.


The participation of aortic proteins in the formation of complexes between low density lipoproteins and intima-media extracts. A factor of protein nature that forms specific complexes with low density lipoproteins (LDL) has been detected in extracts of aortic intima-media from men and rabbits. Although the formation of complexes is maximal at low ionic strength, it is still observed under physiological conditions. Gel electrophoresis of the complex formed between the extracts and LDL proteins indicates that the insoluble material is an aggregate of the lipoproteins with some of the proteins present in the extracts. Pretreatment of the intima-media extract with proteases greatly diminishes its complexing ability. The interaction was also observed between the extracts and sera. The sera from patients with myocardial infarct formed more insoluble complexes than the sera from a control group. The lipoprotein complexing agent was found in intima-media of aorta and coronary arteries but not in that of veins, pulmonary arteries or in the adventitia of arteries or veins.


Endothelial injury. Association with elevations of serum bile acid and cholesterol concentration in biliary-obstructed rats. An association between atherosclerosis, biliary obstruction and hyperlipidemia has been reported in the literature. In previous study from this laboratory, ultrastructural evidence of coronary artery endothelial damage was obtained in rats following ligation-induced biliary obstruction. In the present investigation, serum bile acids, total cholesterol and alkaline phosphatase levels were studied in association with similarly induced biliary obstruction and related to electron-microscopic observations of coronary artery endothelium. The results disclosed marked elevation of all serum parameters in as short a time as 24 hr following ligation compared with shamoperated controls. Animals exhibiting increases of serum bile acids and cholesterol also revealed severe configurational changes of endothelial cells which manifesed as buckling, detachment from the underlying internal elastic lamina, and vacuole formation. The role of elevated circulating bile acids and hypercholesterolemia as possible factors in producing arterial injury through membrane interaction is discussed. These observations suggest that biliary obstruction, even of short duration, may act as a potentially atherogenic mechanism in the experimental animal.


Atherosclerosis in familial lines of pigeons fed exogenous cholesterol. Exogenous cholesterol was fed to F1 pigeons of high and low serum cholesterol differentiated lines of White Carneau and Racing Homer pigeons that had previously been developed by selection and positive assortive mating. The serum cholesterol response of the various high and low lines was dependent upon the breed and the amount of cholesterol in the diet. Racing Homer pigeons were found to be more resistant to aortic atherosclerosis and more susceptible to coronary atherosclerosis than White Carneau pigeons. Data from necropsy examinations showed significant differences in both aortic and coronary atherosclerosis between lines within the White Carneau breed, but no differences between lines of the Racing Homer breed. Mean organ weights for the 4 lines of pigeons were reported.


Effect of cigarette smoking on lipids, lipoproteins, blood coagulation, fibrinolysis and cellular components of human blood. A group of 187 volunteers aged 30-60 years were divided into heavy and light smokers and non-smokers. Heavy smokers smoked over 20 cigarettes per day and light smokers between 5-15, averaging about 7 cigarettes per day. (1) Compared with male non-smokers (N.S.), the male heavy smokers (H.S.) had a higher fasting serum turbidity, higher levels of cholesterol (mainly confined to the ester cholesterol fraction) and higher levels of serum phospholipids and triglycerides. In this H.S. group, the esterified fatty acid index (EFI) of beta and pre-beta lipoprotein were also raised as shown by paper and cellulose acetate electrophoresis. The Stypven clotting times were also shorter than for the N.S. group. (2) Increased levels of triglycerides, pre-beta EFI, longer fibrinolysis times and shorter Stypven times were recorded in the group of female heavy smokers. Changes in cholesterol levels, beta EFI, phospholipids and fasting serum turbidity were not seen in this group. (3) Again, in the male heavy smokers, haematocrit and haemoglobin levels and mean corpuscular volumes were raised. The white cell count (WBC) was very significantly raised and a differential count indicated rises in neutrophils and lymphocytes. These changes were not significant in the female H.S. group. (4) No significant changes were found in the group of light smokers but a trend was usually seen that suggested that these changes were influenced by the number of cigarettes smoked.


Loss of cholesterol from muscle and skin of monkeys treated with nicotinic acid. In Rhesus monkeys, nicotinic acid given daily by subcutaneous injection for 5 weeks brought about a reversible decrease in total cholesterol concentration in skeletal muscle and skin to about half the normal value. The decrease in cholesterol concentration was due to a net loss of cholesterol from muscle, since the treatment had no effect on the water content or on the percentage of DNA or protein in fresh tissue. In muscle, free cholesterol was lost in preference to esterified cholesteol, but in skin both cholesterol fraction were affected to about the same extent. Analysis of the cholesterol content of subcellular fractions of homogenates of muscle showed that loss of cholesterol occurred mainly from the soluble fraction and the 800-g sediment, with no significant loss from the mitochondrial or microsomal fractions.


Rabbit aortic histamine synthesis following short-term cholesterol feeding. The histidine decarboxylase (HD) activity of thoracic and abdominal aortic segments obtained from male, Dutch-belted rabbits fed a diet containing 0.5 per cent cholesterol for periods of either 2 or 4 weeks was examined. Mean thoracic aortic HD activities, expressed as histamine-forming capacity (HFC), were 3911 plus or minus 492, 6254 plus or minus 656, and 6215 plus or minus 878 dpm/100 mg benzenesulfonylhistamine (BSH) for the control group and from rabbits fed cholesterol for 2 and 4 weeks, respectively. Both treatment means were significantly higher than the control (P smaller than 0.05). Similar examination of abdominal aortic HD activities yielded mean HFC's of 4029 plus or minus 399, 5694 plus or minus 521, and 4762 plus or minus 902 dpm/100 mg BSH for control animals and those of the 2- and 4-week treatment groups, respectively. The difference between mean HFC's of the control and 2-week treatment group was significant (P smaller than 0.05). All increases occurred in the absence of either aortic structural alterations or any lipid deposition. These results give credence to the concept that the atherogenic process represents, at least in part, a delayed-prolonged inflammatory response phenomenon of the arterial wall.


Diagnosis of familial hypercholesterolemia by measurement of sterol synthesis in cultured skin fibroblasts. The incorporation of radioactive acetate into the digitonin precipitable fraction (cholesterol) was measured in monolayers of primary cultures of skin fibroblasts. Mean incorporation was increased approximately 20-fold in 4 subjects homozygous for familial hypercholesterolemia (FH) and 4-fold in 6 heterozygotes derived from the immediate family of homozygotes. Incorporation was normal in 4 subjects with Type IV and V hyperlipoproteinemia. In cells that had been preincubated in lipid free medium, incorporation by cells from homozygotes was equal to controls, denoting a derangement in the feedback inhibition of cholesterol synthesis by medium lipids in paralleled the values obtained for sterol synthesis. The assay described could be useful in making an "etiologic" diagnosis of familial hypercholesterolemia and could possible identify variants of monogenic hyperbetalipoproteinemia.


The purpose of occupational medicine.

The purpose of occupational medicine. The purposes of occupational medicine are described in terms of its clinical medical, environmental medical, research, and administrative content. Each of these components is essential in different proportions in comprehensive occupational health services for different industries, and can only be satisfactorily provided by occupational physicians and occupational health nurses who are an integral part of their organizations. Two-thirds of the working population in the United Kingdom are without the benefits of occupational medicine. The reorganization of the National Health Service and of local government presents the opportunity to extend occupational health services to many more workers who need them. It is suggested that area health authorities should provide occupational health services for all National Health Service staff and, on an agency basis, for local government and associated services, eventually extending to local industry. Such area health authority based services, merged with the Employment Medical Advisory Service, could conveniently then be part of the National Health Service, as recommended by the British Medical Association, the Society of Occupational Medicine, and the Medical Services Review Committee.


Circadian variation in physiological responses to exercise on a stationary bicycle ergometer. The responses of six healthy male subjects to submaximal and maximal exercise on a stationary bicycle ergometer have been investigated over a 24-hour period. Measurements were made on each subject at approximately three-hourly intervals and they included minute ventilation at a carbon dioxide output of 1-5 1 min-minus 1 (VE 1-5), tidal volume at a fixed VE of 30 1 min-minus 1 (VT 30), oxygen intake (VO2) at a work load (W) of 150 W (VO2 150), tympanic temperature (Tty) and cardiac frequency at a VO2 of 1-5 1 min-minus 1 (fH 1-5). The experiments were conducted in three parts: on the first occasion two subjects were measured during exercise; on the second occasion a further four subjects were observed in a similar way but starting from a baseline of zero load, and the measurements also included an estimate of cardiac output (Q) using a rebreathing technique. Finally the maximum aerobic power output (VO2max) was measured in three of the subjects in early morning and late evening. Diet and habitual physical activity were held constant between the exercise test on all three occasions. The results show that in the first two subjects fH 1-5 and Tty had a rhythmic pattern of variation with time of day whereas VE 1-5, VT30, and VO2 150 remained fairly constant. The variation in fH 1-5 was associated with Tty; the two variables reached a minimum at similar to 0500 hr and a maximum at similar 1200 hr. These results were confirmed on the remaining subjects but the changes in fH 1-5 and Tty were shown to be more variable and reduced in magnitude. Further, if the changes were calculated from a baseline of zero load, it was shown that the absolute changes observed in fH 1-5 and Tty were not due to the exercise per se but to changes in the basal level from which each subject operated. In addition it was shown that VO2 max and Q remained constant and were independent of the time of day. It is concluded that provided the exercise test conditions are rigidly standardized and subjects exercise from a controlled baseline there is no evidence for circadian variation in the change of responses to work at submaximal or maximal effort.


Carboxyhaemoglobin levels of smokers and non-smokers working in the City of London. The carboxyhaemoglobin (COHb) levels of two groups of workers in the City of London were determined. The mean COHb in smokers (5-8%) was significantly greater than that of the non-smoking group (1-3%). In general, cigarette consumption could be directly related to the COHb level but there was considerable individual variation. The mean COHb level of manual workers was significantly lower than that of sedentary workers even though the former group tended to smoke more heavily.


A comparison of concentrations of lead in human tissues. This postmortem study of lead concentrations in the tissues of 129 subjects is an extension to a report by Barry and Mossman (1970). Lead concentrations in bone greatly exceeded the concentrations in soft tissues and were highest in the dense bones. Bone lead concentrations increased with age in both sexes, more especially in male subjects and in dense bone, varying between mean values of 2-16 ppm in the ribs of children to over 50 ppm in the dense petrous temporal bones of elderly male adults. Male adults contained over 30% more lead in their bones than females. Mean concentrations of lead in the soft tissues varied from less than 0-1 ppm in organs such as muscle and heart to over 2 ppm in the aorta. In most tissues with lead values in excess of 0-2 ppm the male concentrations exceeded female values by about 30%. With the exception of the aorta, spleen, lung, and prostate, lead concentrations did not increase with age in the soft tissues of either sex after about the second decade of life. Children showed concentrations of lead in their soft tissues comparable to female adults, but the concentrations in bone were much lower. It is suggested that children do not possess the same capacity as adults to retain lead in bone. In male adults occupationally exposed to lead the concentrations of lead in bone exceeded the concentrations in unexposed male adults within the same age group by two-to three-fold. Soft tissue lead concentrations between the two groups were less divergent. An assessment of the total body burden of lead revealed higher levels in adult male subjects than in females at mean values of 164-8 mg compared to 103-6 mg, respectively. Over 90% of the total body burden of lead in adults was in bone, of which over 70% was in dense bone. Male adults occupationally exposed to lead had mean total body burdens of 566-4 mg Pb, of which 97% was in bone. The release of lead from bone in conjunction with calcium was not considered to be of physiological significance. Lead concentrations of hair and nails were higher than soft tissue lead concentrations and varied widely. Hair lead measurements were not considered to provide a reliable assessment of lead absorption. The concentrations of lead in tissues of a mixed group of subjects with no known occupational exposure to lead have been shown to be comparable to the findings in earlier studies. Present levels of lead in the environment are not considered to be a hazard to the health of the population in general.


Effects of a single exposure to carbon disulphide on the rate of urea production and on plasma free fatty acid and glucose concentrations in the rat. The concentration of plasma free fatty acids in rats was significantly increased after a short period of exposure to inhalation of carbon disulphide (4 h, 2 mg/1). In contrast, after a longer period of exposure (15 h overnight, 2 mg/1) the concentration of plasma free fatty acid was significantly decreased despite a small hypoglycaemia. At the same time plasma urea concentration was significantly higher in CS2-treated rats. The total esterified fatty acid content of plasma was lower after exposure, but there was no change in plasma glycerol. Following an intragastric water load, no differences were observed in urine flow rate nor in renal clearances of urea and inulin between control and treated rats. It is concluded that the rate of urea production is significantly increased during acute CS2-intoxication, and it is suggested that two factors contribute to this effect: first, an increased breakdown of proteins with which CS2 or its metabolic products have reacted; and secondly an increased rate of utilization of plasma glucose associated with increased gluconeogenesis from amino acid precursors. It is further suggested that the stress effects of CS2 dominate in the short term before being overcome by a diminished sympathetic response. When rats were exposed to CS2 overnight without free access to water, the great vessel haematocrit was significantly lower than in corresponding controls. This was shown to be accounted for by differences in plasma volume. No such difference was observed when rats had free access to water during exposure. These effects probably reflect differing rates of water loss under mildly dehydrating conditions, but a direct effect of CS2 on the cardiovascular system is not excluded.


Dust exposure in manual flax processing in Egypt. Manual flax processing originated in Egypt in 2 000 BC. In the present study a representative sample of the workers involved in this trade, where flax is processed in small workshops or homes, was examined, and their dust exposure was evaluated. The study showed that workers handling and processing flax are exposed to high concentrations of dust; the levels of dust at hackling and combing are considerably higher than at batting and spinning. Byssinosis prevailed in 22-9% of the examined workers, and 18-4% of them had their forced expiratory volume in one second reduced by more than 10% at the end of the first morning work period (4 hours) of the week. Both the rates and the grades of these syndromes increased with duration of exposure. Smoking appeared to be one of the important contributory factors in the production of byssinosis. The relationship between dust concentration and prevalence of byssinosis seems to be curvilinear.


Application of blood cadmium determination to industry using a punched disc technique. A paper disc flameless atomic absorption spectroscopy (AAS) method is described for the determination of cadmium (Cd) in blood, enabling difficulties in sample preparation to be minimized. By control of the ashing step the matrix can be removed without loss of cadmium. Problems with the fast signal response during atomization can be met by spectral band width and temperature control. At the 106 pg level (471 nmol Cd/1 blood; 5-3 mug/100 ml) the relative standard deviation (RSD) was 0-06. Results in four industrial situations are reported. This description of the method should facilitate further investigation of its application to industry using capillary or venous blood.


Effects of general anaesthesia on the intraocular pressure in man. Trichloroethylene in nitrous oxide and oxygen. The effect of TCE on the intraocular pressure was investigated in eight patients under thiopentone nitrous oxide/oxygen anaesthesia, using a muscle relaxant (pancuronium bromide). Pulmonary ventilation was controlled and the end-tidal carbon dioxide was maintained at 5 per cent. In every patient the intraocular pressure was observed to rise as TCE was administered and then to return to the initial level when the administration of TCE ceased.


Biochemical investigation of the subretinal fluid. The level of total protein, protein fractions, sialic acids, and hexosamines was studied in the subretinal fluid (SRF) and blood of patients with retinal detachment. The level of these components in the SRF varied over a considerable range. A low level of total protein, sialic acids, and hexosamines was characteristic of patients with relatively recent clinical forms of retinal detachment, following the most favourable course, and with the best response to surgery. Higher indices were found in patients with marked changes in the fundus oculi, gross destruction of the vitreous body, considerable pathology of the crystalline lens, and correspondingly worse response to surgery. As the pathological changes develop in retinal detachment, there is a parallel increase in the protein levels in the SRF. However, exceptions to this rule indicate that the pathological process may vary. An inverse correlation is found between the level of total protein in the SRF and the electrical sensitivity of the retina. A comparison of the biochemical investigation with the clinical examination suggests that the occurrence of retinal tears and the increase of protein in the SRF are due to the same degenerative processes.


Retinal vascular occlusions in open heart surgery. This study describes microthrombotic emboli (with their ultrastructure) and emboli of fat and of dimethylpolysiloxane with silica in the retinal microcirculation of two patients who died-each after his second open heart operation. The presence of silica was confirmed by electron probe x-ray micro-analysis.


Surgical treatment of chronic papilloedema in children. A surgical technique for optic nerve decompression in children is described and contrasted with other techniques described in the literature. The operation was effective in relieving long-standing disc oedema in two cases in which the swelling was due to raised intracranial pressure. Photographic evidence is presented. The indications for surgery and how its effect is exerted are discussed.


Laser-phakopuncture in the treatment of soft cataracts. A new method of treating soft cataracts by laser irradiation is described ("laser-phakopuncture"). Rupture of the lens capsule can be produced by a strong laser pulse focused on the anterior surface of the lens. This is followed by gradual reabsorption of the lens substance (in much the same manner as with a conventional discission procedure). Pigment deposits on the capsule are usually necessary to ensure sufficient absorption of light energy at the target point. The laser beam can also be employed in a preliminary procedure to produce such pigmented spots, and to prepare the eye for a subsequent laser-phakopuncture. The method was first investigated experimentally on animal eyes. The so-called Q-switched lasers proved to be most effective in producing a tear in the capsule. It was then tried clinically in nine juvenile patients and reabsorption of the lens substance was the eventual result in all cases, although full visual acuity was achieved in only tow of them. These of lasers offers a completely new approach to the treatment of cataract without surgery.


Long-term results of the Choyce anterior chamber lens implants Marks V, VII, and VIII. 68 eyes in which Choyce Mark VIII anterior chamber lenses had been implanted were examined, all surgery having been performed by Mr. Choyce. The average time since implantation was 5-5 years aand in 85 per cent. of eyes the corrected visual acuity was 6/12 or better. Bullous keratopathy, corneal epithelial oedema, and peripheral anterior synechiae giving rise to glaucoma were the most serious complications. Visual result, binocular function, and patient satisfaction were generally very good.


Fibrillary lines of the cornea. A clinical sign in keratoconus. Fibrillary lines, whether in the normal cornea or in keratoconus, are faint structures which must be searched for diligently with the appropriate biomicroscopical settings, using a high magnification and oblique focal illumination of high intensity. They are unlikely to be confused with other superficial linear changes in the cornea, such as mare's tail epithelial lines, fingerprint lines and their variants, ring lines, and so on. A detailed description of these and other entities is given elsewhere (Brown and Bron, in preparation).


Calcium deposition as a cause of spoilation of hydrophilic soft contact lenses. A series of 75 spoilt soft lenses with opacities (mostly manifesting as discrete spots or as large areas of cloudiness, chalk-white in appearance) were subjected to histochemical, electron microscopical, electron probe x-ray microanalytical, x-ray diffraction, atomic absorption spectro-photometric, and biochemical analyses. The results showed that in many cases calcium was implicated in the deposit formation and that a broad correlation existed between the amount of calcium present and the degree of opacification. The possible mode of calcium deposition and resulting implications in lens intolerance are discussed. It is advocated that a search should be made for a modified or new soft lens material which does not permit calcium deposition, and that the medical practitioner should strive towards improved assessment of the systemic and ocular conditions which may help in identifying patients at risk of early lens failure.


Tolosa-Hunt syndrome. The dangers of an eponym. Two cases of painful ophthalmoplegia are described which were initially thought to be examples of the Tolosa-Hunt syndrome. Both were partially responsive to steroid treatment. Subsequent investigations showed that in one case the condition was due to an aneurysm and in the other to a malignant lymphoma.


Solitary choroidal metastasis from bronchial carcinoid. This report describes the clinical, light microscopical, and electron microscopical features of a metastasis from a bronchial carcinoid tumour occurring in a 29-year-old white woman. The eye lesions was diagnosed 30months after resection of the primary pulmonary tumour. Ophthalmoscopically the patient was observed to have a solid choroidal mass. Enucleation was carried out because of the possibility that the tumour was a primary choroidal melanoma. Enucleation was also indicated because of the relatively good prognosis for long-term survival in patients following excision of metastases from a bronchial carcinoid tumour. By light microscopy the metastasis was seen to be composed of cords; and ribbons of cells which showed positive staining characteristics for argentophilia. On electron microscopical study, neurosecretory vesicles, numerous microvilli, mitochondria, and light and dark cells, characteristic of endocrine tissue in different states of activity were noted.


Filarial worm (Loa loa) in the anterior chamber. Report of two cases. Two Nigerian patients with intraocular parasitism by adult Loa loa worms are reported. Whereas Loa loa infestation of the subcutaneous tissues around the eye usually has no permanent effect on visual acuity, in the two cases reported the affected eye became blind.


Anomaly in visual acuity testing in children. A popular and widely used method of visual acuity testing of young children is criticized on the grounds that it often fails to elicit amblyopia. The results obtained when the visual acuity of thirty amblyopic children was tested by different methods show that monotype testing gives an apparent acuity averaging three grades better than those derived from the standard Snellen's test.


The capacity for arylsulfatase synthesis in synchronous and synchronized cultures of Chlamydomonas reinhardti. The green algae Chlamydomonas reinhardti synthesizes arylsulfatase (arylsulfate sulfohydrolase EC 3.1.6.1) by derepression when the concentration of SO4-2-minus in the growth medium is less than about 5-10-minus 5 M. The following observations indicate that the arylsulfatase enzyme is stable while its mRNA was unstable: (1) The increase in enzyme activity stopped and remained constant after addition of cycloheximide to derepressed cells. (2) After readdition of SO4-2-minus the increase in enzyme activity continued at a lower rate whereafter it remained constant. (3) No decay of radioactivity was observed after readdition of SO4 2-minus in labelled enzyme protein isolated from pulse-labelled --S cells. The maximum rate of arylsulfatase synthesis. Measurements of this capacity in cells taken at different developmental stages from a selection synchronous and from a light-dark synchronized culture showed that: (1) Arylsulfatase was derepressible at all stages of the life cycle. (2) The same periodic capacity patterns were found, both with the synchronized and the synchronous cells. Furthermore, the rate of accummulation of RNA and protein changed in the same periodic manner during the life cycle as did the enzyme capacity.


On the application of affinity chromatography to turnover studies on the lactate dehydrogenase isoenzymes. 1. The suitability of a combined application of the techniques of affinity chromatography, double labelling and gel electrophoresis in the determination of the turnover characteristics of the lactate dehydrogenase isoenzymes (L-lactate:NAD+ oxidoreductase EC 1.1.1.27) in rat tissues has been studied. 2. Affinity chromatography was established as affording the advantages of rapidity, high yield and purity to such studies, and the double-labelling procedure was modified to encompass the differential decay kinetics in the separate rat tissues. In addition, a convenient method for the resolution and separate collection of radioactively labelled isoenzymes has been described. 3. Using this methodology, comparative turnover values for the isoenzymes of lactate dehydrogenase and for total soluble protein have been determined. 4. The comparability of these results with other methodologies, and the advantages of this approach in facilitating broad comparative studies on turnover are discussed.


Formation of phagolysosomes containing dextran and Triton WR 1339 in mouse liver. After injection of Triton WR 1339 and dextran into mice, phagolysosomes containing both compounds were obtained from the liver regardless of the order of injection of these materials. This suggests that phagososomes containing the other material. The recoveries of various lysosomal enzymes differed in phagolysosomes after injection of Triton WR 1339 with or without dextran: recoveries of beta-glucuronidase, beta-N-acetylglucosaminidase and arylsulfatase were high, and that of acid phosphatase was low.