Sensory components of bite-force response in the rat. The relative roles of proprioceptive input from the muscles of mastication and the periodontal pressure receptor input from membranes surrounding upper and lower incisors were assessed in animals trained to bite with peak forces within certain bands of forces for water reinforcement. Measures of performance obtained from animals before and after chronic bilateral lesions were made in the mesencephalic nucleus of the trigeminal nerve suggest that proprioceptive input does not play a major role in the differentiation of bite force. However, measures of performance obtained before and after acute peripheral blocking of input from the pressure receptors indicate that these pressure receptors are the main source of input used in bite-force differentiation.


Relatively brief environmental enrichment aids recovery of learning capacity and alters brain measures after postweaning brain lesions in rats. Enriched postlesion experience aided in overcoming effects of simultaneous bilateral cerebral lesions made at 30 days of age in one experiment with inbred Fischer rats and in a second experiment with the Berkeley S1 strain. The lesions were directed to the occipital cortex, but in most cases there was also some impairment of the hippocampus. For 60 days after operations, half of the rats lived in small individual cages and half lived in groups in large enriched-environment cages. They were then pretrained and tested on the standard 12 Hebb-Williams problems. Daily injections of methamphetamine (vs. saline) during the period of differential experience in the first experiment produced no effect on the behavioral scores. The second experiment included groups that received only 2 hr/day of enriched experience, and they benefited as much as groups that remained in the enriched environment 24 hr/day. The results of both experiments demonstrated significant beneficial effects of environment when bilateral lesions were made at a later age and when the periods of enriched experience were shorter than had previously been tested. Two additional experiments revealed significant effects of both lesions and environment on weight and RNA/DNA of brain regions.


Effects of age, strain, and illumination intensity on activity and self-selection of light-dark schedules in mice. Young and senescent albino A/J mice, pigmented C57BL/6J pure inbred mice, and their hybrid F1S were tested under low or high illumination intensities to observe differences in self-selected wheel running, bar pressing, and durations of light and dark over time. The animals (N = 120) were always allowed ad lib access to food, water, running wheel, and bar-press levers. During the pre- and postexperimental phases, the mice were kept under a standard 12:12 hr light/dark cycle; during the experimental phase, however, they were allowed to select their own light and dark schedules by pressing on either of two accessible bars, one light contingent and the other dark contingent. Measures of general running and bar-pressing activities, motivational aspects of illumination change and intensity preferences, time-series analyses of periodicities, power ratios, and significant other multiples were obtained from the subjects during a total of three experimental phases. Age differences were found for most of the measures studied and in general showed declines in activity levels, inccreases in motivation to change illumination conditions, lengthening of activity cycles (slower periods), and decreases in the strengths of the oscillations underlying these behaviors as well as an increase in the number of other periodic components in old mice relative to young. Genetic group and illumination-intensity differences were also found, and the results are discussed in light of theories concerning illumination preference and stimulus change, earlier work involving voluntary light selection behavior, and aging studies.


Role of auditory feedback in canary song development. As in other songbirds, early deafening had drastic effects on the song of the roller canary, a cardueline finch, resulting in a song that was much simpler and more variable than the normal. The repertoire of the syllable types, of which the song is made, was reduced from 30 to a mean of 5.0. Loud white noise was successfully used as a reversible method of cutting off auditory feedback from vocal behavior. Although suffering permanent elevation of hearing thresholds, birds reared in noise to 200 days, singing at first like deaf birds, subsequently increased their syllable repertoires significantly. Birds reared in noise to weaning at 40 days, again partly deaf, achieved a normal repertoire size when stimulated with a singing adult. Without such stimulation the repertoire was significantly reduced, showing that canary song is not fully innate, as had been thought. Although abnormal, the song of deaf canaries retained more species-specific features than did the song of emberizine sparrows when the songs developed without auditory feedback. The results are interpreted in terms of a sensory template theory.


Influence of neonatal septal lesions on DRL performance in adulthood. Two experiments are reported describing the influence of neonatal septal lesions on responding of rats trained on a differential-reinforcement-of-low-rate (DRL) schedule in adulthood. Rats given septal lesions at 1 day or at 7 days after birth emitted a significantly higher number of responses and earned fewer reinforcements than did animals given control electrode insertions. Thus, the inefficient performance on the DRL schedule, often observed after septal lesions in adulthood, does not depend upon the age of the animal at the time of the lesion. Furthermore, operant training given at an early age (25-45 days) to animals with neonatal septal damage did not facilitate performance when the animals were retrained in adulthood. In short, septal lesions at any age lead to permanent impairments of performance on a DRL 20-sec reinforcement schedule.


Developmental analysis of behavioral dysfunction in rats with septal lesions. At 7 days of age, rats received lesions of the septal nuclei or control operations. The rats received 30 hr of training on a schedule that differentially reinforced low rates of responding (DRL 20 sec), 1 hr per day, beginning at either 27 or 96 days of age. At 126 days of age, all subjects received 10 additional training sessions. After operant testing, all subjects were tested on spontaneous alternation, spatial reversal, and passive avoidance. Results indicated that on a DRL 20-sec schedule subjects that received lesions of the septum neonatally and were tested at different ages performed in a similar manner. Approximately 50% of the subjects with lesions of the septal nuclei reached efficiency levels comparable with those of normal controls. When tested for retention, these efficient subjects still performed similarly to normal subjects. Subjects with septal lesions were facilitated in the acquisition of a spatial habit, were deficient in spatial habit reversal, were less likely to demonstrate spontaneous alternation, and were deficient in passive avoidance. It was concluded that neonatal lesions of the septal nuclei produce permanent behavioral impairments on a dirersity of measures and that although juvenile animals with limbic system damage often manifest behaviors different from adult subjects, the difference was not evident during operant testing.


Effect of pregnancy on lactation in mice. Albino mice were used to test the effect of simultaneous pregnancy on lactation in successive lactations. Weights of litters were used to estimate lactational performance by standardizing litters at eight pups on day 1 postpartum and weighing pups immediately after a normal nursing period on days 10, 14 and 20 of lactation. Eight dams were used in each of two treatments:lactating-nonpregnant and lactating-pregnant. Dams were sibling pairs for each treatment to reduce variation. Dams that were simultaneously pregnant and lactating had heavier litters on day 20 of the first lactation and on days 14 and 20 of the second lactation as compared to their lactating-nonpregnant siblings. The results imply that pregnancy provides a stimulus to concurrent and sucessive lactation in the mouse. This may be due to the effect of placental hormones on delaying mammary involution or on maintaining high milk synthesis past day 10 of lactation.


Enhancement of chemotactic response of polymorphonuclear leukocytes into the mammary gland and isolation from milk. Intramammary infusion of saline containing .1% glycogen resulted in diapedesis of numerous leukocytes (93% polymorphonuclear leukocytes) into milk. Direct microscopic somatic cell counts of primary milk 11 h after infusion with 100 ml of either saline containing .1% glycogen, saline, distilled water, or noninfused averaged 4.17, 1.06, .05, and .10 X 10(6) cells/ml of milk. Four times more polymorphonuclear leukocytes were isolated from residual milk (6.1 X 10(9) cells) collected 11 h following infusion than from primary milk (1.5 X 10(9)). The polymorphonuclear leukocytes isolated from either the primary or residual milk collected 11 h after infusion of saline containing .1% glycogen phagocytosed Staphylococcus aureus with great avidity. Sixty-eight percent of a culture of heat-killed phosphorus-32-labeled Staphylococcus auresu (400 X 10(6)) were phagocytosed within 60 min by 25 X 10(6) polymorphonuclear leukocytes. When isolated polymorphonuclear leukocytes were incubated with live Staphylococcus aureus, 98% of the ingested organisms were killed. Isolation of polymorphonuclear leukocytes from residual milk 11 h after intramammary infusion of saline containing .1% glycogen will provide large numbers of polymorphonuclear leukocytes for in vitro studies of the cellular defense of the mammary gland.


In vitro aging of frozen bull semen.

In vitro aging of frozen bull semen. The change in fertility of bull semen with time in storage at -196 C was examined in data on inseminations by the Michigan Animal Breeders Cooperative over 5 yr. Intervals from collection to use were grouped by 10 days for the 1st yr, 30 days for the 2nd yr, 180 days for the 3rd yr, and a single class for semen stored 4 or 5 yr. There were 97,586 first inseminations from bulls with 10 or more ejaculates and from ejaculates with four or more classes. Nonreturn rates for 50-, 60-, 90-, and 180-day intervals post-breeding were calculated. Heterogeneity of quadratic regressions of nonreturn rates on semen age was unimportant. Both regression and least squares analyses were used. Nonreturn rates increased to about 115 days of storage and remained there through the 4 and 5 yr age group. The lowest and highest nonreturn rates for a return interval differed by approximately 4%. Maximum differences in nonreturn rates for different intervals were at the lowest nonreturn rates.


Variation in physical activity as an indication of estrus in dairy cows. Pedometers were used to measure daily physical activity of cows to determine if variation related to estrus was great enough to be useful in estrus detection. Forty cows in free stalls and 28 cows in comfort stalls were studied during the breeding period after calving. Pedometers were enclosed in specially designed cases and attached to a cow's lower rear leg with a plastic ankle strap. Readings were taken twice daily when the cows were milked in a milking parlor. Data from free stalls were available for 5163 intervals between milkings, 87 of which were periods of estrus. Activity definitely increased at the time of estrus; cows were about four times as active during estrus as they were when not in estrus. Data from comfort stalls were available for 2433 intervals between milkings, 39 of which were periods of estrus. Cows in comfort stalls were about 2.75 times as active during estrus as when not in estrus. There was relatively little variation within cow in activity from day to day among cows not in estrus. Activity monitoring appears to have potential as an aid in estrus detection.


Blood plasma and milk prolactin, and effects of sampling technique on composition of milk from suckled ewes. Relations of techniques of sampling milk to its composition and concentrations of prolactin in blood plasma and milk from 59 suckled ewes were compared; Prolactin in milk and blood samples 0 to 2 h (hour 0) after removal of lambs did not differ significantly within autumn or summer, but both were doubled in summer. After the hour 0 sampling (summer only), one side of the udder of each of 12 ewes (group 1) was milked hourly for 4 h, and the opposite side was milked only at 0 and 4 h. Group 2 ewes were milked only at 0 and 4 h and blood was collected from both groups at 0 h and 4 h. Concentrations of prolactin were correlated in pairs of milk or blood samples from the same ewe and in plasma and milk of ewes in group 2 but not in group 1. Prolactin in milk increased between 0 h and 4 h in groups 1 and 2. Although milk lactose and prolactin concentrations differed among hourly samples, their average was similar to that of milk accumulated in the contralateral side for 4 h (group 1). Variations among ewes in progesterone of plasma indicated luteal activity during autumn and none during summer. Prolactin was unchanged in milk stored at -23 C for 30 days. The hour-0 milk-sampling technique was satisfactory to compare among individuals the concentrations of prolactin, total protein, or somatic cells in milk but not percentage fat and lactose, or milk yield due to variable time from last suckling to milking at hour 0.


Heterogeneity in whey proteins of mare's milk. The possible existence of multiple forms in the whey proteins of mare's milk was investigated. When individual milk samples from over 300 animals of various breeds were examined, four forms of an undescribed whey protein could be observed. Based on chemical properties and electrophoretic behavior, this protein has been identified tentatively as Whey1 (Wh1). A single case of heterogeneity in mare's alpha-lactalbumin also was observed. Previously described variation in beta-lactoglobulin could not be confirmed. The results of this study provide further evidence of the widespread, perhaps universal, occurrence of polymorphism in milk proteins.


Twenty-four-hour rhythm in the bronchial hyperreactivity to house dust in asthmatics. Four subjects, 2 males (17 and 35 yr of age) and 2 females (24 and 47 yr of age) suffering from allergic asthma were studied for 10 days in allergen-shielded rooms and without medication. Synchronization of subjects to activity was by light on at 7 A.M. and sleep by light off at midnight. A single bronchial challenge to the threshold concentration of house dust, predetermined for each subject, was presented every other day at designated clock hours such that during a 10-day study span tests were presented at the following times: 8 A.M., 3 P.M., 7 P.M., and 11 P.M. The effect upon bronchial patency determined by FEV 1.0 15 min after house dust inhalation resulted in greatest effect at 11 P.M., while that at 8 A.M. resulted in least effect. The differences were statistically significant (p less than 0.025). Peak expiratory flow (PEF), self-measured at 3-hr intervals throughout the 10-day span, revealed practically no persistence of effect for inhalation of the house dust preparations at 8 A.M.; on the other hand, considerable persistence of effect on airway patency occurred from tests carried out at 11 P.M. The differences between the 24-hr rhythm-adjusted means (mesors) in the PEF for the (24-hr) spans following house dust inhalation at 8 A.M. and 11 P.M. were statistically significant (p less than 0.025) as well.


Beclomethasone dipropionate aerosol in perennial rhinitis. Beclomethasone dipropionate aerosol (BDA), 50 mug four times daily sprayed into each nostril, was compared with placebo in a double-blind crossover trial in 26 patients with perennial rhinitis. Patients received BDA for 3 weeks and placebo for 3 weeks; the order of administration was randomized. Response was assessed with daily symptom score cards and twice weekly measurements of nasal airway inspiratory resistance at a standard flow rate of 0.4 L/sec. Symptom score and nasal resistance during BDA treatment were significantly lower than those duirng placebo treatment (p less than 0.02 and p less than 0.05, respectively) in the third week. Eighteen of the patients expressed a preference for BDA, 6 for placebo, and 2 for neither (p less than 0.05). Acceptable symptomatic improvement (moderate or marked) was achieved by 54%. Mild side effects were noted by 5 patients; these included nasal irritation and bleeding in 2, aerosol-induced sneezing in 2, and headache in 1. These side effects occurred in 3 patients who used BDA, 1 who used placebo, and 1 who used both. After a 6-mo follow-up period, in which the dose of BDA was adjusted and concurrent initial oral prednisone was administered to patients who were treatment failures, 73% of the patients obtained moderate or marked symptomatic improvement. No further side effects were noted during this time. Results in those in whom a possible allergic component could be identified were not different from those of the whole group. We conclude that BDA is a useful addition to the therapy of perennial rhinitis.


Large airway constriction in allergic rhinitis. Extensive pulmonary function tests, including most of the sensitive new techniques capable of detecting small airways obstruction, were performed in 16 asymptomatic patients with allergic rhinitis and 31 normal control subjects. Mean flow rates, lung volumes, and results of tests measuring airways closure, distribution of ventilation, and diffusing capacity for carbon monoxide/alveolar volume did not differ significantly between the groups. Airways resistance (RAW) was significantly higher and specific conductance (SGAW) was significantly lower in subjects with rhinitis. Following administration of nebulized isoproterenol, RAW decreased (p less than 0.001) and SGAW increased (p less than 0.001) to mean values statistically indistinguishable from results obtained in control subjects. Individual results were normal for all tests except RAW and SGAW which were both abnormal in 3 subjects with rhinitis. The results of this investigation indicate that asymptomatic subjects with allergic have large airway (trachea and/or major bronchi) narrowing due to bronchoconstriction and no evidence of diffuse, or small airways, obstruction.


Clinical application of measurements of serum level of bee venom-specific IgE and IgG. Bee venom--specific IgE and IgG antibodies were measured in the serum of beekeeepers, bee-allergic persons, and normal persons infrequently stung without adverse effects. Beekeepers, who are stung frequently and relatively "immune" to bee stings, are characterized by high serum levels of IgG- and low serum levels of IgE-specific antibodies. Bee-allergic individuals have high titers of bee venom--specific IgG. Following a bee sting, allergic individuals develop a rising titer of IgE antibodies, accompanied occasionally by a rise in IgG antibodies. Therapy with whole bee body extracts fail to effect IgE or IgG antibody titers. During the course of venom immunotherapy IgG-specific antibodies are stimulated and IgE-specific antibodies continue to decline. These observations suggest that: (1) bee sting allergy is a function of bee venom--specific IgE; (2) bee sting immunity is a function of bee venom--specific IgG; and (3) bee venom is an appropriate therapeutic antigen.


C1q levels in hereditary angioedema.

C1q levels in hereditary angioedema. In 21 affected members from 4 kindreds with hereditary angioedema, serum C1q levels generally were in the lower part of the normal range, with some values clearly below the lower limit of normal. The serum C1q levels in patients with hereditary angioedema were significantly depressed when compared with those in unaffected family members (p less than 0.001) and healthy control subjects (p less than 0.05). serum C1q levels were significantly (p less than 0.01) related to serum C4 levels which have been used as an indicator of disease activity in individual patients. C1q was stable during storage of serum samples at --20 degrees C for 60 days compared to storage at --70 degrees C. These studies indicate that depressed serum C1q concentrations may be seen in patients with hereditary angioedema and that the finding of this abnormality does not exclude the diagnosis.


An interdisciplinary clinical training program for dietitians. New primary care function. One approach to teaching clinical skills to dietetic interns and students has been described. This approach has been taken to promote the use of on-going dietitian-client relationships where appropriate and to help prepare dietitians to function optimally in such situations. It is hoped that other, different programs will emerge with similar goals, the overall impact being one of developing the potential of dietitians as primary health care professionals in their field of expertise.


Establishing guidelines for peer review of the clinical dietitian. Guidelines for peer review of clinical dietitians are needed. In this study, two areas relevant to such guidelines, i.e., data useful in assessing nutritional status of patients and written communications of the dietary staff with other health care staff, were explored. Admission height and weight and blood chemistries, as found on dietary cards for 119 randomly selected patients during 1973, were tabulated. In addition, pertinent information on dietary cards and in the medical records was compared. The findings indicated that the biochemical and anthropometric indicators of nutritional status were available in the medical records but were not being utilized by dietitians to the degree expected. The dietary card is the logical focus for peer review, but better documentation is needed in areas of dietary history recording, computation of ideal weights, utilization of laboratory data, and development of nutritional care plans.


Folacin in selected foods.

Folacin in selected foods. Representative values for folacin in 299 foods have been developed, based on an extensive literature review. A provisional table of these folacin values has been prepared for foods in 100-gm. portions and for specified weights, representing common household units. The data reflect newer methodology than that used for a prior USDA publication, namely, protection of folacin by ascorbic acid. L. casei is the preferred assay organism. The table includes values for both free and total folacin; however, the authors recommend that, in calculating routine hospital diets, total rather than free folacin be used; this would allow easy and direct comparison with the Recommended Dietary Allowances.


Quantity food production labor time.

Quantity food production labor time. To facilitate the development and use of production time data in quantity foodservice, Master Standard Data (MSD) were applied to determine the feasibility of developing a standard code for synthesizing and predetermining production times. Observations were made in a 2,000-meal-per-day foodservice system to determine basic activities common to the production of single-item entrées. An MSD Quantity Food Production Code was developed through the use of MSD and verified by stop-watch time study. Three formulas for single-item entrées were analyzed, divided into basic elements of production, from which production time for preparation of 100 portions of each entrée was synthesized. Stop-watch studies were performed on three replications of the production of 100 portions of each item. Differences between synthesized time values determined by applying the MSD and stop-watch technique were within acceptable limits. The MSD Quantity Food Production Code was, therefore, considered valid and reliable. Repeated occurrence of similar elements within production methods indicated that the code could serve as a structural framework for establishing a universal data code applicable to all aspects of quantity food production.


Labor time per portion and volume in foodservice. A Master Standard Data Quantity Food Production Code was applied to illustrate the use of predetermined production times in estimating production in relation to volume for two standardized entrée formulas. Labor time per portion was shown to decrease as total production volume increased. However, the decrease in time per portion was not directly proportional to the increase in volume; rather, it resembled an exponential relationship. As volume approached system capacity, the decrease in production time per portion began to stabilize. The availability of a universal standard data code fo quantity foodservice could assist management in determining and optimizing the relationship between time per portion and total volume produced for each menu item utilized.


Are selenium supplements needed (by the general public)? Selenium is an unusual trace element, since both toxicities and deficiencies are known to occur in animals in the United States under natural conditions. Such extremes in the selenium intake of animals are due to the fact that the plants consumed by the animals are often of local origin and there are great geographic variations in the amount of selenium in the soil that is available for uptake by the plants. In contrast to animals, the human population generally draws its foods from several different regions of the country. There is no evidence at this time to suggest that the food supply in the United States contains either too little or too much selenium. There is reason, however, to suspect that indiscriminate selenium supplementation of the diet is potentially hazardous. A well balanced diet is the best way to obtain not only selenium but all of the other nutritionally essential trace elements as well.


A model for statistical forecasting of menu item demand. Foodservice planning necessarily begins with a forecast of demand. Menu item demand forecasts are needed to make food item production decisions, work force and facility acquisition plans, and resource allocation and scheduling decisions. As these forecasts become more accurate, the tasks of adjusting original plans are minimized. Forecasting menu item demand need no longer be the tedious and inaccurate chore which is so prevalent in hospital food management systems today. In most instances, data may be easily collected as a by-product of existing activities to support accurate statistical time series predictions. Forecasts of meal tray count, based on a rather sophisticated model, multiplied by average menu item preference percentages can provide accurate predictions of demand. Once the forecasting models for tray count have been developed, simple worksheets can be prepared to facilitate manual generation of the forecasts on a continuing basis. These forecasts can then be recorded on a worksheet that reflects average patient preference percentages (of tray count), so that the product of the percentages with the tray count prediction produces menu item predictions on the same worksheet. As the patient preference percentages stabilize, data collection can be reduced to the daily recording of tray count and one-step-ahead forecase errors for each meal with a periodic gathering of patient preference percentages to update and/or verify the existing date. The author is more thoroughly investigating the cost/benefit relationship of such a system through the analysis of new empirical data. It is clear that the system offers potential for reducing costs at the diet category or total tray count levels. It is felt that these benefits transfer down to the meal item level as well as offer ways of generating more accurate predictions, with perhaps only minor (if any) labor time increments. Research in progress will delineate expected savings more explicitly. The approach requires statistical and computer expertise primarily during the development of the tray count model and patient preference percentage table. The results of this effort can be transferred to a form that is easily utilized by food management personnel manually to generate menu item demand forecasts.


Nutritive content of college meals. III. Mineral elements. Two samples, each consisting of two breakfasts, two lunches, and two dinners as offered to college students, were collected for seven consecutive days from each fifty colleges. The composited meals for each college were analyzed for five major mineral elements--calcium, phosphorus, magnesium, sodium, and potassium--and five trace mineral elements--iron, chromium, copper, manganese, and zinc. On a per-person-per-day basis, the meals met or exceeded the recommended dietary allowances for nineteen-to-twenty-two-year-old men and women for calcium and phosphorus. Meals from most of the colleges were below the allowance for magnesium, over nine-tenths were short in zinc, and about three-fifths were below the allowance for iron for females but in only one college for males. Average ratios for mineral element to mineral element are reported.


Egg substitutes: use and preference--with and without nutritional information. Three egg substitutes, plus fresh and dried whole eggs, were evaluated by a consumer panel before and after receiving information on cost and caloric and cholesterol content of the products, and before and after sensory evaluations. Initially, most of the thirty panelists believed that the egg substitutes would cost the same or less than fresh eggs. After receiving information on cost and caloric and cholesterol content, the panelists perceived no significant differences in the nutritional value of the products. Fresh whole egg was the preferred product. After tasting, the consumers judged the nutritional value of all of the products higher, but their preferences were lower for all products except the fresh whole egg. Presentation of information on the caloric and cholesterol content of the egg substitutes without explanation of possible benefit in current health problems appears insufficient to change consumers' perception of a fat-modified product.


The three-consideration diet revisited.

The three-consideration diet revisited. Three-consideration diets based on the 1974 Recommended Dietary Allowances, current food composition data, and October 1975 retail prices in Atlanta have been developed for a reference family of four persons. While the diets are less than satisfactory as to variety and palatability, they have a greater degree of variety than three-consideration diets published in earlier decades.


External-cue responsivity as a function of age at onset of obesity. Sixty subjects, averaging 26 per cent overweight, were classified according to age at onset in order to test the external-cue hypothesis of obesity and to investigate the possibility of different "types" of obesity. Subjects were presented with Hershey's kisses wrapped in either transparent (visible) or non-transparent (non-visible) wrappers while performing a sham test; the number of chocolates consumed was the dependent measure. Subjects were placed in four groups: Early onset-food visible (EV), early onset-food non-visible (ENV), late onset-food visible (LV), or late onset-food non-visible (LNV). The first two groups consumed about the same number of chocolates, but the early-onset subjects ate almost twice as many kisses as the late-onset participants. The evidence was inconclusive concerning the external-cue hypothesis, although there was some suggestion that there may be "types" of obesity. The findings are discussed in terms of the need to acknowledge factors other than weight alone in studying and treating obesity.


The biology of aging: 1976, an overview. This article is a comprehensive overview of the biology of aging. The largely unproductive history of research on aging is presented, to lay the groundwork for a discussion of why such research is performed and what aging levels and human models are employed. The anatomic, biochemical, physiologic and behavioral measures used in such studies are delineated. Some of the most promising theories of aging (genetic, autoimmune, viral, free radical) are discussed, as are factors that could prolong the lifespan if optimally employed. Philosophic considerations are emphasized.


Endometrial screening of asymptomatic women by irrigation technique in the private gynecology office. A study was made of 201 asymptomatic women over age 40 (range, 40-74 years) who underwent uterine sounding and endometrial screening by the negative-pressure jet irrigation technique, without anesthesia, in private gynecologists' offices. Introduction of the irrigator was accomplished in 88 percent of these patients. In 97 percent of the successful irrigations, the specimens obtained were satisfactory for cytologic and histologic diagnosis of neoplasia. No occult endometrial carcinomas were discovered. The factors which interfered with endometrial screening by these methods are analyzed. Cervical stenosis prevented endometrial irrigation in 13 of the 24 unsuccessful attempts. Acceptance by the patients was high, in that 74.2 percent reported slight or no discomfort and only 4.7 percent complained of severe discomfort. Although 12.5 percent experienced pelvic cramping after irrigation, no other significant side effects were observed. The results of this investigation indicate the feasibility of using the endometrial irrigation technique for massive screening studies of asymptomatic women who are at risk for the development of endometrial carcinoma.


Histochemical and ultrastructural changes in senile human skeletal muscle. Eighty biopsy specimens of muscles from 79 elderly patients (chiefly in the 60-90 age group) were examined by histochemical and electron microscopic methods. Neuropathic change and type-II fiber atrophy of various grades were prominent findings in the muscles from patients of advanced age. Nemaline rod formation, "ragged red" change and an increase of sarcolemmal nuclei were also common. Several electron microscopic features of the muscle fiber corresponded to those reported for various neuromuscular diseases. Various factors associated with the aging process apparently act on the motor neurons and cause the neuropathic and myopathic changes seen in the muscles of the aged.


A clinical psychogeriatric unit: organization and function. A psychogeriatric unit in Brentwood VA hospital is described with regard to function and organization. Its clinical task is to evaluate the elderly veterans in several dimensions. Then a comprehensive plan emerges for continuing care, to which each professional staff member contributes his own experience. The presenting problems are given priorities, and needed services are coordinated. This process involves staff roles and training, the needs of the population served, diagnostic and treatment procedures, and aftercare programs. Liaison with other agencies addressing the problems of aging provides support in policy-making, consultation and education for the proprietors of homes accepting placement of elderly veterans. It is hoped that the findings of this report (including a clinical study of 47 patients) may serve as a stimulus to others who contribute to the care of the aged.


Mission of the National Institute on Aging. The National Institute on Aging (NIA), the newest of the eleven National Institutes of Health, is dedicated to improving the quality of life of the old in America through biomedical, social, and behavioral research. Aging is reviewed as more than just decline and deterioration; it is also a process of continued development and accumulated knowledge. The NIA will encourage innovative research, but will not support the delivery of health services, as that is the domain of other agencies. In areas of overlap, such as diseases common to the old, the NIA will collaborate with other Institutes. A good target area for collaboration is senile dementia. Other areas of interest to the NIA are: encouraging the incorporation of geriatric medicine as a subspecialty, developing retirement test patterns, and investigating drug-drug and drug-age interactions, personality and social processes, and immunocompetence.


Replantation of digits and hands: analysis of surgical techniques and functional results in 71 patients with 86 replantations. Defining replantation as the restoration of a completely amputated part as opposed to simply restoring circulation to an incompletely severed part, the results of replantation of 86 completely amputated parts in 71 patients performed from January, 1970, to December, 1975, were studied. Twenty-eight, or 32.5 percent, were the result of sharp severances of the part; localized crushing accounted for 56, or 65.1 percent. Two were classified as degloving injuries. Twelve amputations were transmetacarpal, six were at the metacarpophalangeal joints, 14 through the proximal phalanx, 15 at the proximal interphalangeal joint, 21 in the middle phalanx, 13 at the distal interphalangeal joint, and five through the distal phalanx. The technique consisted of bone shortening and fixation and repair of all tendons and nerves if possible. Veins are repaired first, at least two for each artery, and heparinized saline and lidocaine are used locally. Irrigation of the vessels is not done, but an intravenous bolus of 3,000 U. of heparin is given when the anastomoses are completed. Aspirin and low molecular weight dextran are given for 3 to 7 days. For the more distal replantation, heparin may be used. Antibiotics are given. In the total series of 86 completely amputated hand units, 52 were unsuccessful, primarly due to vascular thrombosis and usually on the venous side. In the year 1975 a success rate of 69.2 percent was achieved, whereas in the last 50 replantations, done between Jan. 1, 1976, and Oct. 15, 1976, the success rate was 90 percent. Results improved with more experience in the technique and with more careful selection of patients.


Traumatic amputation of digits: the fate of remaining blood. An experimental and clinical study. Experimental studies on rabbit ears amputated by either a clean sharp division or severed by a crushing blow showed that twice as much blood remained in the crush group. Microthrombi and tissue thrombi were seen in this group only. A review of 142 digital replantations performed over a 10 year period showed 126 survivals. Ninety-three were complete amputations and 80 of these survived; 49 were incomplete amputations and 46 survived after revascularization attemps. Of 74 clear amputations, 68 survived; of 68 crush-type amputations, 58 survived. Circulatory disturbances occurred in 36 replanted digits; 16 could not be salvaged. The primary cause of complications was venous obstruction. In 80 digital replantations done from January, 1974, to December, 1975, success was obtained in 75 (93.75 percent). Irrigation of vessels of the severed part is done only in cases of double level amputation, severely crushed or those due to avulsion. Heparin, low molecular weight dextran, urokinase, and antibiotics are given for several days after operation.


The irrigation jet: an aid in microvascular surgery. Techniques for manipulating and positioning blood vessels during microvascular surgery which utilize a jeweler's forceps tend to inflict significant trauma to the wall and to the intima of the vessel. An irrigation jet device was designed which allows atraumatic positioning of the vessel, gentle and controlled dilation , and better visualization. With this device rat arteries and veins with an external diameter of 0.6 mm. were joined. Upon examination 3 weeks later, over 95 percent remained patent. In addition, vessels of 0.2 to 0.4 mm. were anastomosed successfully with a long-term patency rate of approximately 50 percent. The device has been found to be useful in clinical replantation and revascularization problems in man.


The influence of experimentally induced anemia on the patency of microvascular anastomoses. Anemia, secondary to blood loss or hemodilution, causes reduction of blood viscosity and has been assumed to favor the long-term patency of microvascular anastomoses. This assumption was tested by performing arterial and venous anastomoses on rat vessels measuring 0.3 to 0.8 mm. in external diameter. A group of rats rendered experimentally anemic (whose blood viscocity was lowered by 37 percent) showed no higher patency rates when the involved vessels were examined 3 weeks later than did a control group. The hypothesis that anemia favors higher patency rates was not substantiated.


The reaction of nerve tissue to various suture materials: a study in rabbits. Adult, male white New Zealand rabbits were used to compare two new synthetic suture materials, polyglycolic acid (Dexon) and polypropylene (Prolene), with wire, plain catgut, and silk. The purpose of the study was simply to determine the reaction of nerve tissue to each of the five different materials. No attempt was made to measure functional results. The nerves were examined grossly and microscopically in an effort to evaluate which suture incited the least host reaction. Although no difference was noted in the initial cellular response, Prolene was shown to incite the least fibrolastic response. Silk evoked the most marked fibroblastic response.


Anatomical variations of the median nerve in the carpal tunnel. In 246 hands in which the carpal tunnel was explored at operation, 29 variations in the course of the median nerve were found. Accessory branches at the distal portion of the tunnel were found in 18 hands, a high division of the median nerve in seven, and accessory branches proximal to the tunnel in four. Based upon these findings and including published reports of others, the variations were classified into four groups: I-variation in the course of the thenar branch; II-accessory branches at the distal portion of the carpal tunnel; III-high divisions of the median nerve; and IV-accessory branches proximal to the carpal canal. The thenar branch variations in 100 cadaver hands (Poisel) were extraligamentous in 46 percent, subligamentous in 31 percent, and transligamentous in 23 percent. The findings emphasize the importance of approaching the median nerve from the ulnar side when opening the carpal tunnel.


Denervation of the wrist joint.

Denervation of the wrist joint. A collective review was made of the results of denervation of the wrist joint for painful restrictiorn of motion done in 313 patients and follow-up studies on 195 (average 4.1 years, ranging from 9 months to 14 years). Complete denervation was done in only 30, partial denervation in the others being done after testing with local anesthetic blocks. Sixty-nine of the patients retained a moble wrist without pain or with slight pain with heavy work. No evidence of Charcot-like joints was seen. Poorest results followed when the operation was done for sequelae of intra-articular fracture of the radius, fracture dislocations, unstable ligamentous support, joint surface destruction, or for those required to do heavy manual labor. Arthrodesis was done secondarily in nine patients.


Avulsion of the profundus tendon insertion in athletes. A review of 36 avulsions of the flexor profundus tendon insertion in athletes seen during the past 5 years showed the injury to be most common in the ring finger. The injury was classified into three types depending upon (1) the presence or absence of a bony fragment on roentgenograms, (2) the level to which the tendon retracted, and (3) the status of the blood supply of the avulsed tendon. If the tendon retracts into the palm at the time of injury, it should be repaired within 7 days. If the tendon retracts only to the proximal interphalangeal joint, it often can be repaired a few months after the injury. Late untreated patients who were relatively asymptomatic were left alone. Those with unstable distal interphalangeal joints were treated by fusion or tenodesis of the distal joint. A flexor tendon graft through an intact functioning superficialis tendon in the ring finger seldom was indicated. Prompt diagnosis and surgical repair within the first week gave the best results.


The prevention and treatment of amputation neuromata by silicone capping. A technique of silicone capping of amputated sciatic or tibial nerves was evaluated in a single litter of ten New Zealand white rabbits (eight experimental, two control). All nerves and caps were evaluated 12 and 4 weeks after operation. Neuroma formation was prevented when a lengh:diameter ratio of 5:1 (minimum) to 10:1 (maximum) of the cap was observed and a smooth, filmy, nonreactive capsule around all nerve ends and caps was noted. Eighteen patients with 38 traumatic neuromata in the upper extremity were treated by silicone capping and were evaluated an average of 41 months after operation. Of these 18 patients, 17 underwent revision surgery for the specific purpose of relieving disabling neuroma pain. Two patients developed a causalgic state. One patient had recurrence of symptoms in one of four nerves capped and was relieved by reoperation and recapping. The remaining 15 patients were relieved of their preoperative complaints.


Hyperphalangism: report of a case.

Hyperphalangism: report of a case. A case of hyperphalangism is presented with a review of the literature. Ninety-one cases of this deformity have been recorded now in the literature. This abnormality is inherited as an autosomal dominant. The index and middle fingers show hyperphalangism, which is confused occasionally with nonunion of a fracture. The anatomical features of this unusual duplication are presented along with a simple plan of treatment for the cosmetic aspects of this rare congenital defect.


An improved method for the histochemical localization of glucose-6-phoshate dehydrogenase in animal and plant tissues. An improved procedure is reported for the histochemical localization of glucose-6-phosphate dehydrogenase in fresh-frozen sections of animal and plant tissues. Used in this procedure are an incubation medium and an inert high-molecular-weight polyvinyl alcohol as a stabilizer to check enzyme diffusion. The incubation medium consists of 10 mg each of nicotinamide adenine dinucleotide phosphate and nitroblue tetrazolium chloride and 60 mg of glucose-6-phosphate per 20 ml of 22% polyvinyl alcohol solution in 0.2 M Tris-maleate buffer, pH 7.2. Use of this medium has given consistent results with the tissues tested. Because the use of an electron-transfer agent in the incubation medium often resulted in enzyme diffusion, its use in glucose-6-phosphate dehydrogenase localization is considered undersirable. Incubation time of 15 to 30 min for animal tissue and 20 to 45 min for plant tissue of 37degreesC was found to be optimal for producing the characteristic blue formazan at the reaction sites.


Improvements of glycol methacrylate. I. Its use as an embedding medium for electron microscopic studies. The technique for using the water-soluble embedding medium glycol methacrylate has been improved for ultrastructural studies by the simplification of the method of formation of prepolymers used in embedding the tissue, by the addition of a cross-linking agent so that sections are stable in the electron beam, and by improving the softness of the blocks by the addition of a plasticizing agent. The preservation of tissue morphology has been improved by complete dehydration in glycol methacrylate monomer prior to infiltration with the prepolymer. Preservations of tissue morphology is further enhanced by complete dehydration in ethanols and embedding in the improved glycol methacrylate medium.


A simplified method of "hypothetical grain" analysis of electron microscope autoradiographs. An improved method for the analysis of high resolution electron microscope autoradiographs is described which is simple and quick to perform. The method uses a transparent screen superimposed over the autoradiograph prints to provide information on the distribution of grains over neighboring structures, produced by radioactive disintegrations occurring in different regions of the section. This "cross-scatter" information is used to estimate the radioactivity in different structures without the need to make any assumptions about the size, shape and arrangement of the structures within the autoradiographs being analyzed. The method allows activity in membranes and other linear structures to be determined and also the accuracy attributable to the activity values obtained.


Altered renal cortical reabsorption of protein and urinary excretion of sodium in relation to vascular leakage induced by horseradish peroxidase. The intravenous injection of horseradish peroxidase (HRP) into rats of the Sprague-Dawley strain caused vascular leakage as detectable by a 20-40% increase in the hematocrit and a 15-20% decrease in plasma protein concentration. These changes did not occur when the same amounts of HRP were injected into rats pretreated with antagonists to histamine and serotonin. After pretreatment with the antagonists, the reabsorption of HRP by the proximal tubule cells (the concentration of HRP in the total particulate fractions) showed a 77% decrease and the urinary excretion of sodium showed more than an 80% increase as compared to the values from rats treated with HRP alone. In addition, the blood clearance rate of HRP was decreased and the urinary excretion of HRP was increased after treatment with the antagonists to histamine and serotonin. Cytochemical observations of formaldehyde vapor-fixed tissue also showed the effects of vascular leakage. After the injection of HRP in physiologic or hypertonic saline, the basal infoldings of the proximal tubule cells were strongly peroxidase-positive. When the same amounts of HRP were injected after pretreatment with antagonists to histamine and serotonin, or with mannitol, the basal infoldings were not stained or were stained faintly. Rats of the Wistar/Furth strain did not show the effects of vascular leakage observed with rats of the Sprague-Dawley strains. The questions are discussed as to whether the marked depression of renal cortical HRP absorption by mannitol and hypertonic saline (J Histochem Cytochem 23:707, 1975) is related to the prevention of vascular leakage, and whether the reabsorption of both sodium and protein is increased during the leakage of serum proteins into the interstitial tissue.


Ir-gene control of antibody class production. The antibody response in mice to DNP-insulin is under Ir-gene control. The Ir gene defects in two strains have been analyzed. In both cases the IgG immune response was impaired whereas the IgM response was not affected. One H-2 gene haplotype was characterized by lack of IgG response, independent of the immunization protocol. A second H-2 haplotype manifested a low response of IgG after immunization with Bordetella pertussis as an adjuvant but a high response after complete Freund's adjuvant. It is proposed that a low level of T cell help induces the production of IgM antibodies, intermediate levels allow few IgG clones to develop, and high levels induce a heterogeneous IgG response.


Serologic diagnosis of Lymphogranuloma venereum by counterimmunoelectrophoresis with a Chlamydia trachomatis protein antigen. Previously a protein antigen was identified which was common to members of the species Chlamydia trachomatis and to which antibody could be demonstrated in human sera by two-dimensional immunoelectrophoresis. The antigen has been purified by immunoadsorption chromatography, and an exploration undertaken to determine whether the detection of antibody to this antigen by counterimmunoelectrophoresis would be useful for the diagnosis of C. trachomatis infections. Antibody was found in 43 of 45 (96%) sera from patients with lymphogranuloma venerum proven by either isolation or other serologic methods. No positive reactions were observed in 50 patients with nongonococcal urethritis, 38 of whom had evidence of antibody as measured by microimmunofluorescence with whole organism antigen. Sera were also negative from 50 normal individuals, 10 persons with gonorrhea, and 2 patients with psittacosis. Counterimmunoelectrophoresis with purified C. trachomatis protein antigen appears to be a useful serologic test for diagnosis of lymphogranuloma venereum.


The nature of the local immune system of the bovine mammary gland. The origin of the immunoglobulins of bovine colostrum and milk were examined by using radiolabeled protein. Colostrum was found to consist mainly of immunoglobulin derived from serum, although there was some local synthesis. In lactation the immunoglobulins of milk were almost entirely serum derived. The local immune system was very inactive but could be stimulated to activity by local immunization. The immunoglobulin profiles of the secretion from the stimulated gland were still relatively deficient in IgA compared to other species, notably the pig.


Antibody-mediated suppression of tumor growth. II. Macrophage and platelet cooperation with murine IgG1 isolated from alloantiserum. The effectors that cooperate with IgG1 in causing tumor suppression were identified as exudate macrophages and blood platelets in animals syngeneic and allogeneic to the tumor. Lymphocytes were not active in suppressing tumor growth in the presence of IgG1 antibody, although they were active with whole antiserum.


Antibody-mediated suppression of tumor growth. III. Molecular assay of murine IgG1 alloantibody required to cause tumor suppression in vivo. A radioimmunoassay was used to quantitate the number of tumor cell-bound IgG1 anti-tumor antibody molecules required to cause suppression of tumor growth in C3H mice. Radiolabeled anti-IgG1 was used to detect cell-bound IgG1 antibody. The assay was calibrated by using TNP-coupled tumor cells that had a known number of bound IgG1 anti DNP molecules. Between 70,000 and 130,000 IgG1 anti-tumor antibody molecules per tumor cell were sufficient to cause 50% suppression of tumor growth in mice inoculated with appriximately 50,000 tumor cells.


Alternative pathway of complement: nonenzymatic, reversible transition of precursor to active properdin. A method for the purification of properdin in precursor state (pre-P) has been elaborated. Precursor properdin, in contrast to activated properdin (P), does not initiate the formation of a C3 convertase when added to properdin-depleted serum, rather it requires the presence of an activating substance such as zymosan for expression of its activity. Comparing the activities of pre-P and P it was found that some P preparations contained significant amounts of pre-P because they were fully active only in the presence of zymosan. This observation indicated that P can partly revert to pre-P. Comparison by immunoelectrophoresis and sodium dodecyl sulfate polyacrylamide gel electrophoresis revealed no charge or size differences between pre-P and P. Radiolabeled pre-P, when analyzed after its participation in the reactions of the pathway, displayed an unchanged subunit m.w. of 50,000. Taken together, these results strongly suggest that the transition of pre-P to P is due to a partly reversible change in the conformation of the protein rather than the result of proteolytic cleavage.


Endothelial proliferation in the delayed hypersensitivity reaction: an autoradiographic study. The time-sequence of endothelial proliferation in the delayed hypersensitivity reaction was examined in the skin of guinea pigs. Animals were sensitized to tuberculin (PPD) and dinitrochlorobenzene (DNCB) and skin lesions were examined 12 hr to 7 days after challenge. Thirty minutes before sacrifice 3H-thymidine (3H-T) was injected i.p. and endothelial labeling was assessed in autoradiographs of 1.5-mu thick methacrylate sections. Endothelial labeling became manifest at 24 hr (PPD) and 12 hr (DNCB) after challenge, reaching a peak at 48 to 72 hr in PPD-sensitized animals and 36 to 48 hr in DNCB-sensitized animals. Peak labeling indices were 7.88 and 15.08%, respectively. Labeling indices for nonsensitized control groups were always less than 1%. Endothelial labeling was associated, in time of occurrence, distribution, and magnitude with mononuclear cell infiltration of the lesions. These findings thus document the occurrence of significant endothelial cell proliferation in delayed hypersensitivity responses and suggest that the events leading to the expression of hypersensitivity also result in endothelial replication.


Schistosomiasis in the congenitally athymic (nude) mouse. I. Thymic dependency of eosinophilia, granuloma formation, and host morbidity. Athymic nude mice (Nu/Nu), heterozygous littermates (Nu/+), and thymus reconstituted homozygous animals (Nu/Nu TXR) were exposed to Schistosoma mansoni cercariae. A marked impairment in the development of peripheral blood eosinophilia and hepatic granuloma was observed in the Nu/Nu animal. In addition, host morbidity judged by organ weight, portal pressures and reticuloendothelial activity were less in the Nu/Nu animal. Thymus-reconstituted animals demonstrated eosinophilia, increased granuloma size, and morbidity equivalent to that shown by the Nu/+ heterozygous littermates. These studies indicate that the eosinophilia, granulomatous hypersensitivity, and ultimate host morbidity, associated with murine schistosomiasis, is dependent on thymic dependent lymphocyte function.


Immunologic characteristics in relation to high and low leukemogenic activity of radiation leukemia virus variants. II. Analysis of the immune response. Comparative analysis of immune responses induced by two variants of the radiation leukemia virus having high (A-RadLV) or low (D-RadLV) leukemogenic potential was performed. Effective immunization could be induced only with RadLV variants having low leukemogenic potential when injected into adult mice of specific strains, (D-RadLV in C57BL/6 mice and A-RadLV in (BALB/c X C57BL/6)F1 mice). Immunologic cross-reactivity among the RadLV variants and the leukemic cells induced by them was demonstrated in several systems. Transplantation resistance could be induced in certain strains against challenge of leukemic cells induced by both RadLV variants. Isoantisera, raised in the suitable strains, could neutralize effectively the leukemogenic activity of both A-RadLV and D-RadLV. Leukemic cells induced by each of the variants shared cell-surface antigens. Circulating anti-tumor antibodies, induced by both variants in the appropriate strains, lysed efficiently the target leukemic cells.


Human transfer factor: fractionation by electrofocusing and high pressure, reverse phase chromatography. The biologically active fraction of human transfer factor (Sephadex G-25, fraction III) has been separated by exclusion chromatography into two component fractions (IIIa and IIIb). Fraction IIIa transferred donor reactivities to PPD or KLH into 9 of 9 recipients. Fraction IIIb did not transfer donor reactivities (0 of 8 transfers) but did produce both antigen-independent and antigen-dependent dermal reactions in recipients. Fractionation by electrofocusing and high pressure reverse phase chromatography revealed that IIIa has a major UV254 absorbing component and that fraction IIIb has at least three major and three minor UV absorbing components. The major component of IIIa was isolated by preparative electrofocusing, had an isoelectric point of 1.6, and transferred KLH reactivity to four of five recipients.


Immunity to lymphoid tumors in syngeneic mice by immunization with mitomycin C-treated cells. Immunization of mice with syngeneic mitomycin C-treated lymphoid tumor cells (EL-4 and S49A) conferred a high degree of immunity to transplantation with viable tumor cells in syngeneic animals. The development of this immunity was paralleled by the development of specific cell-mediated cytotoxicity; no anti-tumor antibodies could be detected in the immunized animals. In contrast to the high immunoprophylactic capacity of mitomycin C-treated cells, attempts to utilize these cells for immunotherapy were unsuccessful. Preliminary experiments did not reveal antigenic differences between mitomycin C-treated and untreated tumor cells.


Effects of local immunization with glucosyltransferase fractions from Streptococcus mutans on dental caries in rats and hamsters. The effect of local immunization with glucosyltransferase enzymes of Streptococcus mutans on dental caries in conventional rats, hamsters, and gnotobiotic rats was studied. Injection of these animals with crude or defined glucosyltransferase enzyme preparations incorporated into complete Freund's adjuvant consistently resulted in the presence of antibody in saliva demonstrable by functional inhibition of enzymatic activity and binding of radioactive enzyme. Serum antibody was also present. Two experiments have been completed in conventional rats and one in gnotobiotic rats in which the animals were immunized with crude enzyme antigens. The immunized groups of animals always had lower mean caries scores than comparably sham-immunized or nonimmunized control groups. Hamsters immunized with a defined enzyme preparation, containing no more than three antigenic components (two of which were enzyme), also demonstrated significant reductions in mean caries scores. The numbers of lesions were also always lower in immunized animals. In some cases there were reductions in the numbers of S. mutans that could be recovered from the teeth of immunized, infected animals. The reductions in dental caries and lesions were greater on smooth dental surfaces than on occlusal surfaces, which might be explained as interference with adherence phenomena demonstrated by S. mutans. It is proposed that antibody interference affects dental caries caused by this organism.


Activation of the classical complement pathway by Fc fragment of human IgA. Intact Fcalpha fragments from five human IgA myeloma proteins were produced by two different methods, high temperature trypsinolysis and IgA protease digestion. Three of the Fcalpha fragments activated the classical pathway as determined by the titers of the individual complement components. Two other fragments did not fix complement by either pathway.


A simple method for obtaining peritoneal macrophages from chickens. A simple technique for inducing the production of peritoneal exudate cells within 3 to 4 days in chickens is described. In each 5 to 6 week old chicken, 5 to 8 ml of washed Sephadex particles suspension in saline (3%) were injected intraperitoneally. Three to 4 days later, peritoneal exudate cells were harvested, washed, suspended in Hank's solution, counted and adjusted to one million cells per ml. In each well of 4-chamber slide 1 ml of peritoneal cell suspension was incubated at 37 degrees C for 30 min. Cultures were then gently washed several times leaving a monolayer of glass adherent cells. The phagocytic activity of these adherent cells was examined using either latex particles or antibody-sensitized sheep erythrocytes. The monolayer cells were incubated with particles in Hank's solution (with excess particles in particle/peritoneal cell ratio) for 1 h at 37 degrees C. From 99.5 to 100% of the monolayer cells were found actively phagocytic for either the latex particles or sensitized erythrocytes or both. Adherent cell monolayers were cultivated in vitro for several weeks with no detectable decrease in their phagocytic activity.


Determination of RNA antibodies in serum and unconcentrated CSF by counterimmunoelectrophoresis. A quantitative counterimmunoelectrophoresis technique has been applied to evaluation of RNA antibodies in serum and unconcentrated CSF. Serum anti-RNA antibodies have been found at high dilutions in some patients with infectious diseases, subacute panencephalitis and multiple sclerosis. RNA antibodies in CSF are significantly linked to oligoclonal aspect, i.e. to a synthesis of IgG inside the CNS.


Cryopreservation of mouse peritoneal macrophages. A method for the preservation of mouse peritoneal macrophages is described. Using 5% dimethylsulphoxide with either a cooling rate of 1 degree C/min or two-step cooling with 10 min interruption at -30 degrres C allows 80% survival as judged by pinocytic activity. An important finding was that the cells must be handled at 0 degrees C both before and after freezing.


Kinetics of staphylococcal opsonization, attachment, ingestion and killing by human polymorphonuclear leukocytes: a quantitative assay using [3H]thymidine labeled bacteria. A method has been developed for studying quantitatively the separate processes of bacterial opsonization, phagocytosis, and killing by human polymorphonuclear leukocytes using [3H]thymidine labeled Staphylococcus aureus. Phagocytosis is determined by assaying for leukocytes-associated radioactivity after differential centrifugation and washing the leukocytes. Opsonization is studied by incubating bacteria with an opsonic source for varying durations and then adding leukocytes. By treatment of samples with the muralytic enzyme, lysostaphin, the attachment and ingestion phases of phagocytosis can be separated. Sampling for colony forming units after disruption of the leukocytes permits the measurement of bacterial killing. Using this method, differences in the kinetics of staphylococcal opsonization by normal and C2 deficient sera were defined, opsonic influences on the attachment and ingestion phases of pH agocytosis were delineated, and the influences of different opsonins and leukocyte populations on killing were determined.


UVA erythema in skin: is it a sunburn?

UVA erythema in skin: is it a sunburn? Specimens obtained from human skin following the induction of erythema responses with long ultraviolet (UVA) and with middle ultraviolet (UVB) radiation alone were compared histologically to determine whether the effects of these two portions of the electromagnetic spectrum were the same. It was found that, except for similar dermal inflammatory changes, the effects of UVA were not the same as those of UVB; characteristic epidermal sunburn damage was induced by the latter, but not by the former.


The effects of indomethacin on long-wave ultraviolet-induced delayed erythema. Indomethacin, a known inhibitor of prostaglandin synthesis, administered topically as a 2.5% solution, intradermally in 10 mug doses, and orally in a dose of 150 mg/day for 2 days did not diminish the delayed erythema produced a long-wave ultraviolet light (320-400 nm). The delayed phototoxic erythema produced by 8-methoxypsoralen and subsequent exposure the long-wave ultraviolet light was similarly unaffected. By comparison, topical and intradermal indomethacin treatment produced sustained decrease in the erythemal response to ultraviolet radiation in the UVB ranges (290-320 nm).


Cytologic and metabolic effects of prostaglandins on rat skin. The cellular and metabolic effects of exogenous prostaglandins E1, E2, and F2alpha (PGE1, PGE2, and PGF2alpha) were studied in the skin of rats by using scintillation counting, autoradiography, electron microscopy, and scanning electron microscopy. Radioactivity measurements demonstrated that prostaglandins of the E series induced a marked increase in the incorporation of [3H]leucine, [3H]thymidine, [3H]uridine, and [3H]proline in the rat skin, mostly at 1 hr, whereas PGF2alpha inhibited this phenomenon. Light microscopic autoradiography revealed an increased incorporation of [3H]leucine in the cytoplasm of hyperplastic epidermis of PGE-treated rats; also, the incorporation of [3H]thymidine, [3H]uridine, and [3H]proline was significantly increased over the epidermal nuclei, nucleoli, and the collagen fibers of PGE-treated rats. Electron microscopy revealed ultrastructural changes of the epidermal cells and fibroblasts following PGE administration, including an increase in polyribosomes, endoplasmic reticulum, keratohyaline granules, and enlarged intercellular spaces; PGF2alpha induced advanced cytolysis and cell disintegration, with increased lysosome formation. Scanning electron microscopy showed hypertrophied collagen fibers in PGE-treated rats; however, a disruption and disintegration of collagen fibers occurred in PGF2alpha-treated rats. The level of PGE1 in the skin of treated rats was markedly elevated as compared to those of controls. These findings demonstrate that prostaglandins are potent regulators for the epidermal cell ultrastructure and metabolism as well as for collagen synthesis.


Photoprotection in erythropoietic protoporphyria: mechanism of photoprotection by beta carotene. Erythropoietic protoporphyria is a genetic disease caused by the accumulation of protoporphyrin IX. This molecule absorbs 400-nm light and its presence is at times associated with severe cutaneous photosensitivity. The only effective treatment for this disease is oral administration of beta carotene. Several possible mechanisms of photoprotection by beta carotene were investigated using the photohemolysis of red blood cells as an in vitro model. Additional studies were done in an in vivo model which involves lethal hematoporphyrin photosensitization of white mice. The photoprotective effects of beta carotene were compared with those of alpha tocopherol, an agent which possesses some but not all the properties that have been implicated in explaining the known effectiveness of beta carotene. In the photohemolysis model, both compounds demonstrated partial protection. In hematoporphyrin-photosensitized mice, tocopherol showed some protection at high doses, while beta carotene showed greater protection at lower concentrations. Although these results suggest that photoprotective was due to free radical scavenging or singlet oxygen quenching, properties common to both agents, they do not rule out the possible role of 400-nm light absorption, a property of beta carotene alone.


Assessment of topical anti-inflammatory activity in rats with cantharidin-induced inflammation. Topical application of 400 mug of cantharidin to the rat's ear caused an approximate doubling in the mean weight of uniform ear punch samples when compared to vehicle-treated controls at 72 hr, and produced a maximal response at 7 days. Dexamethasone reduced the increase in weight when applied topically, but was ineffective when given subcutaneously or orally at the same doses. Hydrocortisone, prednisolone, triamcinolone, betamethasone, flurometholone, paramethasone acetate, fluocinolone acetonide, fluocinonide, and flurandrenolide showed significant suppression of cantharidin-induced inflammation. Cholesterol, diphenhydramine, tripelennamine, chlorpheniramine, promethazine, cyproheptadine, epinephrine, phenylephrine, alpha-tocopherol, indomethacin, and bufexamac were inactive. It is suggested that the procedure employed may be useful in the screening and evaluation of topical anti-inflammatory agents.


Persistent effect of antibiotics on Staphylococcus aureus after exposure for limited periods of time. Persistent suppression of bacterial growth by certain antibiotics was tested by periodic counts of viable organisms in a culture of Staphylococcus aureus that had been incubated in media containing drugs for limited periods of time and then removed by centrifugation. During short (2 hr) periods of exposure of test cultures to penicillin G, cephalothin, erythromycin, clindamycin, vancomycin, and tetracyline, effects on the growth of S. aureus were produced that persisted after removal of the drug for periods of 1.7-4.1 hr. A persistent antibiotic effect was not observed with gentamicin. The persistent effects of penicillin G and erythromycin were directly related to duration of exposure and concentration of drug, up to a point of maximal response. The maximal durations of bacterial suppression after exposure to penicillin G and erythromycin were approximately 2 and 5 hr, respectively. These effects were observed over a wide range of inocula.


Hepatitis B in subjects treated with a drug containing immunoglobulins. In late  1974 and early 1975, several cases of viral hepatitis were reported in Italy among subjects who had received subcutaneous injections of a drug containing human immunoglobulins that was prescribed for the treatment of allergies. Epidemiologic and laboratory investigations provided evidence that the original immunoglobulins, the series of the drug containing these immunoglobulins, and sera from a number of patients were all positive for hepatitis B surface antigen (HBs Ag) of the adw subtype, which is relatively rare in Italy. Some sera from patients and healthy subjects treated with the HBs Ag-positive drug were also found to be positive for antibody to HBs Ag of the adw subtype. The clinical course of the disease was consistent with typical forms of icteric hepatitis in all patients examined. The average length of the possible incubation period was 111-143 days, and an inverse relation was observed between the number of doses administered and the length of the incubation period. The possibility that immunoglobulins can be responsible for the transmission of viral hepatitis raises a number of theoretical and practical problems concerning control and use of these blood products.


Current status of rubella in the United States, 1969-1975. Implementation of the rubella immunization policy in the United States has resulted in marked decreases in the number of reported cases of both rubella and CRS. Emphasis on immunization of one- to 12-year-old children has resulted in a dramatic reduction in reported rubella in this age group. Accordingly, the proportion of reported cases occurring in adolescents and young adults has increased. Therefore, it seems appropriate to place more emphasis on immunizing susceptible adolescent and adult females as an adjunct to routine immunization in early childhood. This joint strategy should result in a further decrease in the incidence of rubella and CRS.


On the mechanism of lithium-induced renal tubular acidosis. The effect of lithium chloride administration on urinary acidification was studied in dogs. Lithium-treated dogs developed hyperchloremic metabolic acidosis with alkaline urine. Bicarbonate loading resulted in a normal increase in urinary Pco2 in normal dogs but failed to produce the same response in lithium-treated dogs. The bicarbonate titration curve of lithium-treated dogs revealed a small leak of bicarbonate at low plasma levels of bicarbonate; at high plasma levels bicarbonate reabsorption was significantly higher in lithium-treated dogs. This pattern of bicarbonate reabsorption is identical to that described in classic distal renal tubular acidosis. Sodium sulfate administration resulted in a normal urinary acidification ilithium-treated dogs. It is possible that lithium administration induces distal renal tubular acidosis by allowing excessive back-diffusion of acid. This excessive back-diffusion of acid would result in a low urinary Pco2 during bicarbonate loading. Sodium sulfate administration, by increasing the negative intratubular potential, would restrict back-diffusion of hydrogen ion and thereby result in a normal acidification in lithium-treated dogs. We previously demonstrated that postureteral obstruction of the kidney fails to increase urinary Pco2 during bicarbonate loading and to lower urinary pH with sodium sulfate. It is possible that a low urinary Pco2 during HCO3 loading can occur as a consequence of either diminished hydrogen ion secretion (postobstructed kidney) or excessive back-diffusion of acid (lithium administration). Further studies are indicated to determine whether both mechanisms may be found in patients with distal renal tubular acidosis.


Effect of amphotercin B on urine acidification in rats: implications for the pathogenesis of distal renal tubular acidosis. It has been proposed that distal renal tubular acidosis is a gradient-limited disorder an that the low urine Pco2 observed in this condition is caused by back diffusion of carbonic acid. This study was designed to examine this hypothesis using the amphotericin B model of gradient-limited distal renal tubular acidosis in rats. After induction of acute metabolic acidosis the minimum urine pH in 12 of 24 amphotericin B-treated rats exceeded 5.63 (mean 5.76 +/- 0.04), whereas it was 5.41 +/-0.04 in control rats. These animals with impaired urine acidification were presumed to have a gradient lesion and were studied in bicarbonate-loading experiments. The urine minus blood Pco2 gradient in these rats was 24.9 +/- 1.5 mm. Hg, a value similar to that of the control rats (26.7 +/- 2.1 mm. Hg). The presence of a normal urine minus blood Pco2 value in this experimentally induced gradient-limited type of acidification lesion indicates that a permeability defect for hydrogen ions was not associated with a similar defect for carbonic acid and that the urine minus blood Pco2 gradient is a valid index of distal nephron hydrogen ion secretion in amphotericin B-like gradient-type lesions.


Rheological evaluation of hemoglobin S and hemoglobin C hemoglobinopathies. The concept of optimum hematocrit was used to compare the rheology of bloods from patients with various hemoglobin S and hemoglobin C hemoglobinopathies. The technique involved the utilization of cone and plate viscometric data to predict average flow rates under representative physiological-fluid mechanical conditions. The shape of the curve relating optimum hematocrit to oxygen tension, rather than the absolute magnitude of the optimum hematocrit at fixed oxygen tension, is shown to give an indication of clinical severity of the disease.


Maintenance of low screen filtration pressure in blood stored in a new liquid medium: BAGPM. Formation of microaggregates in blood stored in conventional media is reflected by rapidly rising screen filtration pressure (SFP). We show that the BAGPM (bicarbonate, adenine, glucose, phosphate, and mannitol) blood preservation system maintains SFP at near normal levels throughout the storage period of 42 days. Whenever the SFP had a tendency to rise in BAGPM blood, filtration through a routine in-line blood filter reverted SFP back to baseline levels. Blood from the same donors stored in citrate-phosphate-dextrose (CPD) adenine had a rapidly rising SFP by 7 to 14 days of storage. Filtration through the routine blood filter had no effect on the SFP of blood stored in CPD-adenine, CPD, or ACD. BAGPM not only maintains adequate levels of ATP and 2,3-diphosphoglyceric acid (2,3-DPG) during full 42 days of storage but also offers a unique system in which microparticulate material is prevented from forming, with maintenance of low SFP, perhaps because of its low leukocyte, platelet, and fibrinogen content.


Characteristics of stroma-free hemoglobin prepared by crystallization. Stroma-free hemoglobin was prepared from outdated human red cells by crystallization. After hemolysis with water and toluene and low speed centrifugation, the solution was dialyzed against 2.8M phosphate buffer. Hemoglobin crystals formed within the dialysis casing and were washed with phosphate buffer. After being dissolved in water, dialyzed against kidney dialysis fluid, and sterilized by Millipore filtration, the hemoglobin solution obtained had normal serum potassium, sodium, and osmolality. Spectral maxima and minima were characteristic for oxyhemoglobin, and cellulose acetate electrophoresis showed a sharp, well-defined hemoglobin band and slight contamination with carbonic anhydrase. The crystallized hemoglobin solution showed no coagulant activity, and preparation from group A cells showed no blood group A activity by hemagglutination inhibition. Methemoglobin was less than 0.28 gm./dl. and did not increase with storage at refrigerated temperature for a period up to 6 months. The P50 ranged between 15 and 18 mm. Hg at pH 7.4 and n values were normal.


Uroporphyrinogen III cosynthetase in liver and blood in the Dubin-Johnson syndrome. The activities of uroporphyrinogen III cosynthetase in blood lysates from five patients with the Dubin-Johnson syndrome (DJS) and four control subjects and in liver homogenates from four patients and four control subjects were determined. No significant difference was found in enzyme activity between the two groups in either blood lysate or liver homogenate. These results indicate that low urinary coproporphyrin III output in the DJS is not due to deficiency of uroporphyrinogen III cosynthetase in the liver and the erythropoietic system.


Regulation of plasma lecithin:cholesterol acyltransferase. II. Activation during alimentary lipemia. The effect of dietary fat on plasma lecithin:cholesterol acyltransferase (LCAT) activity has been investigated in 14 normal male subjects. After determination of postabsorptive lipid and LCAT levels, a high-fat liquid test meal (1 to 2 gm./kg. body weight) was fed, followed by lipid and LCAT determinations at 2.5 hour intervals. Plasma triglycerides were elevated by 2.5 hours, peaked at 5.0 hours, fell at 7.5 hours, and were normalized by 10 hours. LCAT was unchanged at 2.5 hours but was elevated by 5.0 hours, exhibiting a broad plateau through 10 hours. Most subjects manifested peak responses at 7.5 hours. The mean maximal increase in individual subjects was 37.2 +/- 13.3 (S.D.) percent. LCAT changes similarly followed the elevation and recession of chylomicrons (Sf greater than 400) and very-low-density lipoprotein triglycerides, both of which closely paralleled plasma triglycerides. Enzyme responses were proportional to percentage elevations of plasma triglycerides (r = 0.93, p less than 0.01) and related to quantity of fat in the test diet. Three subjects who ingested the test diet devoid of the fat component showed no significant change in enzyme activity. Enzyme progress curves revealed linearity for 3 hours for both postabsorptive and lipemic (7.5 hour) plasma from the same subjects, supporting the validity of the assay as a measure of enzyme rate. These studies demonstrate an increase in cholesterol esterifying activity temporally related to the clearance of alimentary particles, suggesting a physiologic role in the clearance process.


Myelopoiesis in the infected burn.

Myelopoiesis in the infected burn. A modified bone marrow clonal cell culture technique was used to study granulocyte production during burn injury and sepsis. When rats were inflicted with a 30 percent third-degree scald burn, marrow cellularity and colony-forming units in culture (CFU-C) per 10(5) marrow cells increased progressively to four times normal by 7 days after injury. Conversely, When animals were burned and the burn wound immediately seeded with 10(8) Pseudomonas organisms, CFU-C declined steadily until the day of death and reflected a progressive loss in marrow cellularity. Further studies were conducted replacing or mixing standard colony-stimulating serum with burn, burn-infected, or normal rat serum. The results indicated that colony-stimulating activity could be supplied by postburn serum, but not with normal or burn-infected rat serum. Additionally, serum from burned-infected animals significantly inhibited colony formation when added to the standard colony-stimulating serum. Marrow failure appears to be the major cause for granulocytopenia in burn infection and may partly be serum mediated.


Size and weight of glomeruli isolated from human diabetic and nondiabetic kidneys. A sieving technique was used to isolate human glomeruli and to fractionate them by size in order to determine whether nondiabetic and diabetic glomeruli can be separated from one another on the basis of size and mass and to observe the effects of diabetes on the physical properties of glomeruli. The kidneys studied were from five diabetic patients and five nondiabetic controls that were age- and sex-matched. About 40 percent of the glomeruli in the samples of renal tissues were isolated for study. The preparations consisted of more than 90 percent glomeruli, and over 90 percent of the glomeruli were isolated whole. The mean diameter of the diabetic glomeruli was 45 percent greater than that of nondiabetic glomeruli. The mean mass of the diabetic glomeruli was 2.5 times greater than the mean nondiabetic glomerular mass.


Effect of phosphate depletion on renal tubular reabsorption of glucose. The renal handling of glucose was evaluated in six dogs before and after chronic phosphate depletion of 51 to 112 days' duration. Phosphate depletion was produced by feeding the dogs with phosphate-restricted diet and administration of Al(OH)3. With phosphate depletion, serum phosphate fell from 3.5 +/- 0.36 (S.E.) to 0.5 +/- 0.19 mg./dl. Both TmG and TmG/GFR fell significantly during phosphate depletion. TmG/GFR was 4.0 +/- 0.41 mg./ml. before phosphate depletion and 2.9 +/- 0.19 mg./ml. after phosphate depletion. In four phosphate-depleted dogs TmG/GFR fell precipitously after glucose loading for more than 200 minutes, and practically all of the filtered glucose was excreted in the urine. It is possible that the levels of cytosolic adenine nucleotides which are required for energy of the renal cell may be reduced during phosphate depletion. This may underlie the fall in TmG and may explain the precipitous fall in TmG when the transport mechanism for glucose was operating at maximum capacity for a prolonged period of time.


Reliable identification of reovirus-like agent in diarrheal stools. In recent reports, reovirus-like particles have been identified in stools of children with diarrhea by using several different methods of preparing the stools for electron microscopy. These papers have reported varying incidences of the reovirus-like agent (RLA) in groups of patients with diarrhea. Since no standardized stool processing method has been used, it is difficult to compare the incidence figures which have been published. This study evaluates two commonly used methods to determine which would be more sensitive for use in future clinical studies. Stool samples from 72 Mexican children who had acute-onset diarrhea were processed for reading on the electron microscope by the pseudoreplica technique and by differential centrifugation. Reovirus-like particles were seen in 25 samples (34.7 percent) when the results of both methods were combined. With the pseudoreplica technique 22 samples (30.6 percent) contained the viral particles; with differential centrifugation 21 (29.2 percent) had particles. This study demonstrates that the two methods are equally reliable for demonstrating reovirus-like particles in stool samples. We believe that the pseudoreplica technique, which is quicker and less expensive than differential centrifugation, is the preferred method for clinical studies of diarrhea associated with reovirus-like particles.


Effects of hyperthermia on hypoxic ventilatory response in normal man. Increased body temperature stimulates hyperventilation in man but little is known about its effects on ventilatory responsiveness to hypoxia. Hence this study examined the effects of hyperthermia on hypoxic ventilatory response (HVR), hypercapnic ventilatory response (HCVR), and oxygen consumption (VO2). Six fasting subjects had these variables measured under basal conditions and at two levels of hyperthermia. Hypoxic ventilatory response was measured as the shape paramater A of the VE/PAO2 curves. Since hyperthermia produces hyperventilation and, therefore, hypocapnia, HVR was measured at the hyperthermic (hypocapnic alveolar CO2 tension (PACO2) and at the basal (normothermic) PACO2. Hypoxic ventilatory response (A) increased when measured at basal PACO2 levels, from 113 +/- 8.8 (S.E.M.) to 189 +/- 21.8 at 0.7 degrees C. and 240 +/- 34.0 at + 1.40 degrees C. (P less than 0.005). HVR measured during hyperthermic hypocapnia also increased at each temperature level but did not reach statistical significance (P = 0.1). Hypercapnic ventilatory response, as measured by the slope S of VE/PACO2 lines, increased significantly at each temperature elevation (P less than 0.025). We conclude that raising body temperature causes a significant augmentation of ventilatory responses to hypoxia (during normothermic PACO2 conditions) and to hypercapnia.


Decreased surface charge and accelerated senescence of red blood cells following neuraminidase treatment. Female LAF1 mice were given single or repeated injections of V. cholerae N'ase and the effects on circulating RBC surface charge and life span were determined. Intravenous injection of N'ase caused a rapid decrease in RBC surface charge of approximately 14 percent, and survival of such treated cells was reduced by approximately one fifth by virtue of an acceleration of senescence. When RBC's were treated in vitro with N'ase, a comparable (14 to 17 percent) reduction in surface charge was seen. Such cells, when injected into intact mice, showed a similar acceleration of senescence. When N'ase was injected intravenously into splenectomized mice, RBC survival was similar to that of controls. Intravenous injection of N'ase 1 hour before injection of labeled RBC's did not alter RBC survival nor did it accelerate the clearance of carbon particles by the RES. These results indicate that N'ase accelerates senescence in treated mouse erythrocytes by acting on the RBC's and not by activating the RES. Absence of this effect in splenectomized mice implicates the spleen as the sensor of the induced alterations in surface charge. These results and those recently reported for treated RBC's in the dog, rat, rabbit, and man suggest that at least a portion of the phenomenon of RBC senescence may be related to the loss of RBC surface charge.


Hemopoietic stem cell dynamics in 89Sr marrow-ablated mice. 89Sr was used to ablate the marrows of 12- to 16-week-old CAF1 mice. The CFU-S of their blood, marrows, and spleens were assayed at intervals from days 10 through 56. The effects of splenectomy performed on day 14 or 42 on the numbers of CFU-S in the blood and marrow were also studied. On day 10 after treatment with 89Sr both the cellularity and CFU-S of the marrow were markedly decreased. Later, especially during the third week after treatment, marrow cellularity increased and by day 56 had returned to 74 percent of normal; the concentration of marrow CFU-S also increased but by day 56 had attained a level of only one-third normal. Thus, replenishment of the marrow's CFU-S lagged behind the repletion of its cellularity. Spleen and blood CFU-S were elevated throughout the 56 days. The number of splenic CFU-S was highest at day 10, decreased somewhat by day 21, and remained remarkably stable thereafter. After splenectomy there was a significant decline in the content of both blood and marrow CFU-S, whereas the reverse occurred in the "cold" 88Sr-treated control group. The results of these studies suggest that in the 89Sr-irradiated animal the spleen is transformed from a trapper to the prime supplier of CFU-S and that in normal mice the spleen may suppress marrow CFU-S proliferation. An inverse relationship between the size of the pool of mature granulocytes and the number of CFU-S was found, suggesting that the granulocyte compartment may, at least in part, play a role in the regulation of CFU-S proliferation.


Potentiation by collagen or epinephrine of platelet responsiveness to aggregation. The possible role of substance(s) released from platelet membranes. When human platelets in plasma were exposed to a small amount (nonaggregating concentration) of collagen, epinephrine, or arachidonic acid, their responsiveness to aggregating agents was potentiated and they were aggregated by a subsequent addition of nonaggregating concentrations of the stimulants. Otherwise the nonaggregating concentrations of the stimulants were incapable of inducing platelet aggregation. The potentiation of platelet responsiveness to aggregating agents was also caused by collagen- or epinephrine-treated platelet membranes. Furthermore, the soluble fraction of collagen- or epinephrine-treated membranes contained some material responsible for platelet potentiation, indicating that the responsible material was released from platelet membranes by collagen or epinephrine. It is suggested that the material may be arachidonic acid or its derivatives related to prostaglandins, since the soluble fraction of collagen- or epinephrine-treated membranes contained a larger amount of the precursor(s) of prostaglandin Falpha than the untreated membranes.


The effect of concomitant mercuric chloride and gentamicin on kidney function and structure in the rat. In order to define the possible effects of gentamicin on the course of experimental acute renal failure, the interaction between gentamicin and mercuric chloride was studied in rats. Acute renal failure was induced with 1 mg. of HgCl2 per kilogram intravenously. When given alone, HgCl2 produced a uniform, reproducible, nonoliguric, acute renal failure with a low mortality rate. Animals receiving gentamicin over the course of HgCl2-induced acute renal failure, in doses sufficient to produce a 1 hour postinjection serum concentration of 10 mug/ml., recovered glomerular filtration in a fashion similar to animals receiving only HgCl2(p greater than 0.05). Animals that recovered from HgCl2-induced acute renal failure were given 10 mg./Kg. of gentamicin every 4 hours for 15 days and developed proteinuria and decline in urine osmolality to the same degree as animals given gentamicin alone, but failed to develop azotemia. Nevertheless, morphological changes associated with gentamicin nephrotoxicity were found which were similar in severity to those seen with gentamicin alone. Animals pretreated with 10 mg./Kg. of gentamicin every 4 hours for 7 days were then given HgCl2. Acute renal failure in these animals was more severe than in animals receiving HgCl2 alone, as manifest by a greater degree of azotemia and death (p less than 0.05). The data indicate that in the rat the concomitant administration of gentamicin did not interfere with recovery from HgCl2-induced renal failure. Rats recovering from HgCl2-induced acute renal failure were resistant to a depression in glomerular filtration when given gentamicin. The prior administration of gentamicin enhanced the nephrotoxicity of HgCl2.


Interaction between ethyl methylene blue and cyanide-induced increases in blood lactate. Previous workers have reported that ethyl methylene blue (EMB) diminishes cyanide-induced increases in blood lactate (CIL); the present study investigates the mechanism underlying this interaction. Accordingly, sodium cyanide (1.2 mg./Kg.) was infused into the abdominal aorta of anesthetized, spontaneously breathing dogs. Following cyanide infusion, arterial lactate concentration increased 5.4 +/- 1.1 mmol./L. and arterial PCO2 decreased 22 +/- 3 mm. Hg. A second group of dogs was pretreated with EMB (8 to 15 mg./Kg.); this dose of EMB elicited twofold increments in oxygen consumption and induced the formation in vivo of methemoglobin (0.8 +/- 0.1 gm./100 ml.). Following cyanide infusion, the increase in lactate in EMB animals was only 0.6 +/- 0.2 mmol./L.; the decrease in arterial PCO2 was limited to 5 +/- 1 mm. Hg. In order to clarify the relationship between cyanide-induced hypocapnia and CIL, cyanide was infused into a third group of dogs that were maintained isocapneic via mechanical ventilation; despite constancy of arterial PCO2, lactate increased 6.0 +/- 0.7 mmol./L. To determine the effect of EMB-induced tissue hypermetabolism on CIL, twofold increments in oxygen consumption were produced in a fourth group of dogs by pretreatment with sodium salicylate. Following cyanide infusion, salicylate-pretreated animals increased lactate 7.2 +/- 1.2 mmol./L. In order to assess the relationship between EMB-induced methemoglobinemia and the decrease in CIL, similar concentrations of methemoglobin were produced in two subsequent groups of dogs by two different techniques (i.e., by aniline pretreatment or by infusion of methemoglobinemic blood that had been prepared in vitro by addition of sodium nitrite). CIL in these animals was again markedly diminished (i.e., increments of only 0.6 +/- 0.3 mmol./L.) It is concluded that EMB diminishes CIL by a mechanism other than elimination of cyanide-induced hypocapnia or induction of tissue hypermetabolism. The results suggest that methemoglobin formation may completely account for the ability of EMB to effect a decrement in CIL.


Liver as the primary site of erythropoietin formation in the fetus. Fetal sheep produced significant amounts of erythropoietin in response to bleeding. Bilateral nephrectomy prior to bleeding failed to influence the formation of erythropoietin. Removal of the spleen, in addition to kidneys, was also without effect. Subtotal hepatectomy prior to bleeding, however, inhibited erythropoietin formation in these fetuses. In situ perfusion of the liver, but not the kidney, resulted in the appearance of significant quantities of the hormone in the perfusate. These results suggest that the liver is the primary site of erythropoietin production in the mammalian fetus.


Radioimmunoassay for serum transcobalamin II. A radioimmune assay for transcobalamin II (TC II) was devised from the following: (1) TC II-57Co B12 precipitated from normal serum with (NH4)2SO4 as the labeled ligand; (2) the TC II of whole serum as the standard source of TC II; (3) rabbit anti-pure TC II as the binding agent; (4) separation of the bound and free TC II-B12 by precipitation of the antibody bound with polyethylene glycol. The assay was responsive to either TC II or TC II-B12 and to TC II either pure or in crude preparations. It was not responsive to R-type binders of B12. The median TC II of 10 normal sera was 890 pg. per milliliter and of 10 sera from 10 random hospital patients was 1,010 pg. per milliliter. There was no measurable TC II in the serum of a child with congenital absence of TC II and the assay measured levels greater than 5,000 pg. per milliliter in abnormalities of TC II metabolism.


A method for measurement of fibrin monomer with the use of an immune precipitate of fibrinogen. A semiquantitative test for measuring fibrin monomer in human plasma is described. The test is based upon the ability of fibrin monomer to form a complex with an immune precipitate of fibrinogen. The test is not sensitive to the plasmin digestion products of fibrinogen and relatively insensitive to plasmin digestion products of fibrin. The test is easily performed on small quantities of plasma in approximately 2 hours.