Showing papers by "University of North Carolina at Chapel Hill published in 1971"
TL;DR: A theory of epidemiologic transition, sensitive to the formulations of population theorists who have stressed the demographic, biologic, sociologic, economic and psychologic ramifications of transitional processes, was conceived by this author less than four years ago.
Abstract: Although demography continues to be the most prominent discipline concerned with population dynamics, involvement of other disciplines is highly desirable. The case for a multidisciplinary approach to population theory has been aptly stated by Kurt Mayer: “Any meaningful interpretation of the cause and effects of population changes must … extend beyond formal statistical measurement of the components of change, i.e. fertility, mortality and migration, and draw on the theoretical framework of several other disciplines for assistance (Mayer 1962).” In noting that the “analysis of the causal determinants and consequences of population change forms the subject matter of population theory,” Mayer inferentially acknowledges the epidemiologic character of population phenomena, for as its etymology indicates, (epi, upon; demos, people; logos, study), epidemiology is the study of what “comes upon” groups of people. More specifically, epidemiology is concerned with the distribution of disease and death, and with their determinants and consequences in population groups. Inasmuch as patterns of health and disease are integral components of population change, epidemiology's reservoir of knowledge about these patterns and their determinants in population groups serves not only as a basis for prediction of population change but also as a source of hypotheses that can be further tested to correct, refine and build population theory. Furthermore, many epidemiologic techniques that have heretofore been limited to the examination of health and disease patterns can be profitably applied as well to the exploration of other mass phenomena, such as fertility control.
A theory of epidemiologic transition, sensitive to the formulations of population theorists who have stressed the demographic, biologic, sociologic, economic and psychologic ramifications of transitional processes, was conceived by this author less than four years ago. Recognition of the limitations of demographic transition theory and of the need for comprehensive approaches to population dynamics stimulated the development of this theory (Van Nort and Karon 1955; Micklin 1968).
2,043 citations
TL;DR: Assuming random mating and random sampling of pedigrees, the likelihood of a set of pedigree data is developed in terms of the population distribution of the different genotypes.
Abstract: Assuming random mating and random sampling of pedigrees, the likelihood of a set of pedigree data is developed in terms of: (1) the population distribution of the different genotypes; (2) the phenotyp
1,480 citations
TL;DR: Administration of 6‐hydroxydopamine to developing rats lowered both noradrenaline and dopamine concentrations as well as the tyrosine hydroxylase activity in the brains of these animals.
Abstract: 1. After intracisternal administration, 6-hydroxydopamine had a greater effect on brain noradrenaline than on dopamine.2. Administration of two doses of 6-hydroxydopamine increased the depletion of noradrenaline but not of dopamine.3. Small doses of 6-hydroxydopamine decreased the concentration of noradrenaline with little or no effect on dopamine. Tyrosine hydroxylase activity was not reduced with these treatments.4. While pargyline pretreatment offered no advantage in the depletion of brain noradrenaline after 6-hydroxydopamine, depletion of brain dopamine was greatly potentiated by this treatment. The reduction of striatal tyrosine hydroxylase activity observed after 6-hydroxydopamine was also potentiated by pargyline pretreatment.5. The amounts of labelled noradrenaline and dopamine formed from (3)H-tyrosine were greatly reduced by 6-hydroxydopamine treatment. After (3)H-DOPA, formation of noradrenaline was greatly reduced while formation of labelled dopamine was only moderately reduced suggesting that decarboxylation of DOPA can occur in other than catecholamine containing neurones.6. Desmethylimipramine and imipramine inhibited depletion of noradrenaline produced by 6-hydroxydopamine but did not alter depletion of dopamine. Reserpine did not inhibit depletion of catecholamines produced by 6-hydroxydopamine.7. Administration of 6-hydroxydopamine to developing rats lowered both noradrenaline and dopamine concentrations as well as the tyrosine hydroxylase activity in the brains of these animals.
535 citations
TL;DR: Feynman path integration for multiply connected space systems of indistinguishable particles, considering bosons and fermions propagators was studied in this paper, where it was shown that the path integration can be done in a deterministic manner.
Abstract: Feynman path integration for multiply connected space systems of indistinguishable particles, considering bosons and fermions propagators
326 citations
TL;DR: Studies are described which characterize a number of aspects of MTX transport in L12 I0 leukemia cells, Ehrlich ascites tumor cells, and rabbit erythrocytes which relate these findings to the transport characteristics of the naturally occurring folatcs.
Abstract: The translocation of amethopterin (MTX) * across the tumor cell membrane plays an important role in determining the cytotoxic effectiveness of this agent.’ This has provided a stimulus for the investigation of the transport properties of the folate analogues in malignant This report describes studies from this laboratory which characterize a number of aspects of MTX transport in L12 I0 leukemia cells, Ehrlich ascites tumor cells, and rabbit erythrocytes. Other studies are presented which relate these findings to the transport characteristics of the naturally occurring folatcs.
317 citations
TL;DR: The use of a cube function of the echographic minor axis was an accurate predictor of volumes only in smaller ventricular chambers, but overestimated volumes in larger hearts.
Abstract: We compared dimensions of the left ventricular minor axis (S) measured at enddiastole (SD) and end-systole (SS) by echocardiography with dimensions and left ventricular volumes measured by biplane angiocardiography in 27 patients with diverse cardiac abnormalities. There were high correlations between echographic and angiographic ventricular minor-axis dimensions (r = 0.85 for SD and 0.87 for SS), between echographic dimensions and ventricular volumes (r = 0.84 for end-systolic volume [ESV] and SS, 0.83 for end-diastolic volume [EDV] and SD), and between the relative change in the echographic minor axis with systole (% Δ S) and ejection fraction (r = 0.79). Regression formulae were derived from these relationships which allowed calculation of ventricular volumes from echo dimensions alone: ESV = 47 SD—120, EDV = 59 SD—153. These equations allowed relatively accurate prediction of volumes over a wide range of ventricular sizes. The use of a cube function of the echographic minor axis was an accurate predic...
300 citations
TL;DR: In this paper, the randomized response technique of reducing respondent bias in obtaining answers to sensitive questions is extended from the situation where response is categorical to that in which the response is quantitative, and results are reported on the application of the method to estimating mean number of abortions in an urban population of women, and mean income of heads of households.
Abstract: The randomized response technique of reducing respondent bias in obtaining answers to sensitive questions is extended from the situation where response is categorical to that in which the response is quantitative. Results are reported on the application of the method to estimating mean number of abortions in an urban population of women, and mean income of heads of households. The efficiency of estimators based on the method of moments in the randomized response procedure is studied and representative results are reported and discussed.
300 citations
TL;DR: Comprehensive surveillance of acute lower respiratory illnesses of children seen in apediatric group practice was maintained for 67 months in Chapel Hill, North Carolina, and consistent patterns have been observed in the clinical manifestations, seasonal occurrence, and age and sex distribution of infections.
264 citations
TL;DR: It was shown that Mycoplasma pneumoniae would infect man with resulting pneumonia; this proved that M. pneumoniae was a cause of human disease.
Abstract: Mycoplasmas, formerly called pleuropneumonialike organisms, have been known for many years to be important causes of veterinary diseases, but Mycoplasma pneumoniae is the only member of this group of agents with proven pathogenicity for man. Mycoplasma pneumoniae was first isolated in the early 1940s by Eaton and his coworkers from a case of primary atypical pneumonia [1]; it was considered to be a virus until the early 1960s, when Marmion and Goodburn suggested that it was a pleuropneumonia-like organism [2]. Shortly after this, Chanock and his associates were able to grow the organism on artificial medium, providing further proof of its nature [3]. Finally, it was shown that it would infect man with resulting pneumonia; this proved that M. pneumoniae was a cause of human disease [4].
254 citations
Book•
17 Aug 1971248 citations
TL;DR: Hybridization experiments have shown that EB viral DNA comprises between 0.06 and 1.6% of the total DNA of Burkitt lymphoma cells and established leucocyte cell lines.
Abstract: Hybridization experiments have shown that EB viral DNA comprises between 0.06 and 1.6% of the total DNA of Burkitt lymphoma cells and established leucocyte cell lines.
TL;DR: Initial outcome trends are presented, indicating that parents have been developing effective skills as cotherapists, and Objective recognition of their children's disabilities has helped to improve family equilibrium.
Abstract: A treatment program for psychotic and autistic children in which parents are helped to function as primary developmental agents is described and evaluated. Research and clinical experience is reviewed suggesting that parents react to their child's developmental disorder, rather than cause the disability. Demonstrations to parents observing through a one-way screen have been focused on corrective approaches to relatedness, competence motivation, cognitive, and perceptual motor functions. Parental participation has also included program sessions and research activities at home. The latter corroborated clinical observations that autistic children responded best to high external structures for acquiring new patterns and to relative freedom to practice those which have been mastered. Initial outcome trends are presented, indicating that parents have been developing effective skills as cotherapists. Objective recognition of their children's disabilities has helped to improve family equilibrium. Substantial improvements in participating children have been noted. Optimal or normal levels of development are prognosticated, depending on IQ, consistency of appropriate education and degree of impairment.
TL;DR: The marketing concept sparked the interest of business executives and marketing educators when introduced as a pioneering idea some twenty years ago as discussed by the authors, and has since influenced the thinking of marketing educators and business executives.
Abstract: The marketing concept sparked the interest of business executives and marketing educators when introduced as a pioneering idea some twenty years ago. The doctrine has since influenced the thinking ...
Journal Article•
TL;DR: The results obtained show that the most immediate and direct factor responsible for cytotoxicity of the compounds studied is the introduction of the O=C-C=CH 2 system.
Abstract: Summary A number of naturally occurring sesquiterpene lactones have been studied for cytotoxic activity against three different cell lines. The results obtained show that the most immediate and direct factor responsible for cytotoxicity of the compounds studied is the introduction of the O=C-C=CH2 system.
TL;DR: Basal lamina and anchoring fibrils were absent from the freshly trypsinized epidermis before grafting although hemidesmosomes and tonofilaments of the basal cells remained intact, and basal lamina became progressively more dense and extended to become continuous in many areas at the epidermal-dermal interface from the fifth to the seventh day after grafting.
Abstract: The purpose of this investigation was to study the formation and origin of basal lamina and anchoring fibrils in adult human skin Epidermis and dermis were separated by "cold trypsinization" Viable epidermis and viable, inverted dermis were recombined and grafted to the chorioallantoic membrane of embryonated chicken eggs for varying periods up to 10 days Basal lamina and anchoring fibrils were absent from the freshly trypsinized epidermis before grafting although hemidesmosomes and tonofilaments of the basal cells remained intact Basal lamina and anchoring fibrils were absent from freshly cut, inverted surface of the dermis Beginning 3 days after grafting, basal lamina was noted to form immediately subjacent to hemidesmosomes of epidermal basal cells at the epidermal-dermal interface From the fifth to the seventh day after grafting, basal lamina became progressively more dense and extended to become continuous in many areas at the epidermal-dermal interface Anchoring fibrils appeared first in grafts consisting of epidermis and viable dermis at five day cultivation and became progressively more numerous thereafter In order to determine the epidermal versus dermal origin of basal lamina and anchoring fibrils, dermis was rendered nonviable by repeated freezing and thawing 10 times followed by recombination with viable epidermis Formation of basal lamina occurred as readily in these recombinants of epidermis with freeze-thawed, nonviable dermis as with viable dermis, indicating that dermal viability was not essential for synthesis of basal lamina This observation supports the concept of epidermal origin for basal lamina Anchoring fibrils did not form in recombinants containing freeze-thawed dermis, indicating that dermal viability was required for anchoring fibrils formation This observation supports the concept of dermal origin of anchoring fibrils
TL;DR: In this paper, the dynamic equations of orthotropic laminated plates are derived from the concepts of Timoshenko's beam theory to include the effects of transverse shear and rotatory inertia.
Abstract: The dynamic equations of orthotropic laminated plates are derived from the concepts of Timoshenko's beam theory to include the effects of transverse shear and rotatory inertia. The propagation of flexural waves is discussed. The transient response of a rectangular plate to a normal impact is investigated. We also consider briefly the influence of internal friction related to the damping on the response of the plate.
TL;DR: Following exposure to saccharin, rats were injected with 0, 21, or 37 mg/kg of cyclophosphamide, which had a highly significant effect in two-stimulus tests and had no significant effect on Saccharin preference in one- Stimulus tests.
Abstract: Weanling and mature rats were presented with saccharin or saline solutions for 1 h on alternate days. Following exposure to saccharin, rats were injected with 0, 21, or 37 mg/kg of cyclophosphamide. Injections had no significant effect on saccharin preference in one-stimulus tests, but had a highly significant effect in two-stimulus tests.
TL;DR: The findings suggest that the pathogenicity of M. pneumoniae depends upon intimate extracellular infection with production of functional and structural changes initiated by host cell membrane injury.
Abstract: The interaction was studied between Mycoplasma pneumoniae and its natural host cell, the human respiratory epithelium. Organized, ciliated cells provided by fetal trachea in organ culture enabled examination of the host-parasite relationship by light, immunofluorescence, and electron microscopy. Impairment of cellular function was reflected by disorganization and loss of ciliary motion; this was associated with a sequence of cytopathological changes denoting progressive cell injury. The organisms were found concentrated on the luminal surface of ciliated epithelium and cells lining the submucosal glands. A differentiated portion of the Mycoplasma, consisting of an extension of the unit membrane containing an electron-dense core surrounded by a lucent space, served as the means of attachment to host cells. The findings suggest that the pathogenicity of M. pneumoniae depends upon intimate extracellular infection with production of functional and structural changes initiated by host cell membrane injury.
TL;DR: It is found that DHLNL is the major reducible crosslink of mineralized collagens, comprising up to 60% of the total radioactivity, and reduction with NaBD4 shows that a portion of the Schiff base precursor of D HLNL becomes reduced in vivo.
TL;DR: Rat epididymis cytosol contained 2 androgen-binding components, one of which demonstrated a high affinity for dihydrotestosterone, and radioactivity migrated in a single peak with sedimentation coefficient of 4S in comparison with the 3.5S and 8S peaks of prostate cytosols.
Abstract: Rat epididymis cytosol, labeled by incubation with dihydrotestosterone-l,2-3H at 0 C or by injection of testosterone-l,2-3H sc, contained 2 androgen-binding components, one of which demonstrated a high affinity for dihydrotestosterone. The mean constant of dissociation (Kd) of the high affinity component was 7.0 × 109M as determined by methods of dextrancoated charcoal adsorption, sucrose gradient ultracentrifugation and Sephadex gel equilibrium. When epididymis cytosol labeled with dihydrotestosterone-l,2-3H, in amounts which are bound largely by the high affinity binding component, was fractionated by sucrose gradient ultracentrifugation, the radioactivity migrated in a single peak with sedimentation coefficient of 4S in comparison with the 3.5S and 8S peaks of prostate cytosol. Acrylamide gel electrophoresis of similarly labeled epididymis cytosols revealed 2 peaks of radioactivity, while prostate contained only a single peak corresponding to the slower moving epididymis peak. Rat serum and cytosols of...
TL;DR: This work has attempted to minimize problems in demonstrating tolerance to marijuana and its active constituents by using only those constituents of marijuana that have been shown to have activity in man and are available in relatively pure form and by using standardized procedures for measuring the development of tolerance in several species.
Abstract: Tolerance to a drug is said to have developed “when, after repeated administration, a given dose of a drug produces a decreasing effect, or conversely when increasingly larger doses must be administered to obtain the effects observed with the original dose.”’ There is evidenv that tolerance develops to the effects of marijuana and its active constituents in animaW6 and in man.7 However, many investigators have not observed tolerance to marijuana or its active constituents in animalss and in mang-lls or have suggested that the repeated administration of marijuana may result in an increased sensitivity to the subjective effects of marijuana in man.12 There are many factors that might have contributed to the conflicting findings concerning the development of tolerance to marijuana. Among the most serious of these factors has been the difficulty in controlling the dose level of the active constituents in marijuana, due to the varying purity of the preparations from the plant material.I3 Since tolerance to a drug is defined either in terms of a diminishing response to a constant dose or in terms of a constant response to graded increases in the dose, failure to control the dose adequately makes the demonstration of tolerance difficult. Other problems in demonstrating tolerance to marijuana and its active constituents may arise from differences in the methods used to assess tolerance and from species differences. We have attempted to minimize these problems by using only those constituents of marijuana that have been shown to have activity in man14-17 and are available in relatively pure form,ls and by using standardized procedures for measuring the development of tolerance in several species. Recently, schedule-controlled behavior has been used as a sensitive and stable baseline for assessing the development of tolerance to a number of d r ~ g s ~ * ~ J ~ ~ ~ in several species. The basic techniques for studying schedule-controlled behavior are well known.22 In our experiments, pigeons are trained to peck a translucent plastic response key in order to obtain a four-second access to mixed grain. Each peck breaks an electrical circuit, which permits the peck to be counted and recorded. Occasionally, depending on the schedule of food reward, pecks produce access to grain. The reward schedule for pigeons that has been used most often in tolerance s t ~ d i e s ~ ~ J ~ is the multiple fixed-ratio 30-response, fixed-interval fiveminute (mult FR 30 FI 5) schedule of food presentation. Under this schedule, when a blue light behind the translucent key is on, 30 key pecks are required to produce food (FR 30 component), and when a red light behind the key is on, the first key peck after five minutes produces food (FI 5 component). The two schedule components alternate throughout a session, with a 40-second time limit applying to both components of the schedule, so that the schedule can change automatically from one component to the other component if the pigeon is not responding at the time food is available. At these schedule parameters, pigeons usually respond at a high steady rate under the FR component, while responding under the FI 5 component is characterized by a pause early in the interval, followed by an increasing rate of responding as the availability of food appr0aches.2~
TL;DR: Cytidine deaminase has been purified approximately 160-fold from extracts of Escherichia coli B and exhibits an affinity for this inhibitor exceeding by more than four orders of magnitude its combined affinity for the products uridine and ammonia.
TL;DR: Administration of a small dose of pentagastrin, a synthetic pentapeptide containing the biologically active portion of the native hormone gastrin, results in a marked, rapid, transitory increase in thyrocalcitonin secretion in the pig.
Abstract: Administration of a small dose of pentagastrin, a synthetic pentapeptide containing the biologically active portion of the native hormone gastrin, results in a marked, rapid, transitory increase in thyrocalcitonin secretion in the pig. Gastrin or a related gastrointestinal peptide may be important in the physiological secretion of thyrocalcitonin, such as that which occurs when calcium salts are introduced into the gastrointestinal tract.
TL;DR: To determine the number and molecular weights of the structural polypeptides of simian virus 40, purified virus was analyzed by electrophoresis on 14% polyacrylamide gels containing sodium dodecyl sulfate and found VP4, 5, and 6 may form a nucleoprotein in the virion, and VP3 may serve as an intermediate structural component.
Abstract: To determine the number and molecular weights of the structural polypeptides of simian virus 40, we have analyzed purified virus by electrophoresis on 14% polyacrylamide gels containing sodium dodecyl sulfate. Full virus purified by several different methods showed six distinct bands with molecular weights of approximately 43,000 (VP1, containing 70% of virion protein), 32,000 (VP2, 9%), 23,000 (VP3, 10%), 14,000 (VP4, 6%), 12,500 (VP5, 4%), and 11,000 (VP6, 3%) both by analysis of radioactively labeled virions and by visualization of the polypeptide bands after staining. "Empty" virions contain decreased amounts of VP4, 5, and 6. The approximate molecular ratios of the polypeptides were 6.0, 1.0, 1.5, 1.5, 1.1, and 1.0. When virus degraded in an alkaline buffer was analyzed by velocity centrifugation in sucrose gradients, the two larger polypeptides (VP1 and VP2) remained at the top of the gradient, whereas the three smallest polypeptides (VP4, 5, and 6) sedimented as a complex with the viral deoxyribonucleic acid. VP3 was found in association with either VP1 and 2 or VP4, 5, and 6, depending on the conditions of degradation. Presumably, VP1 and VP2, comprising about 80% of the protein, form the capsid of the virus. VP4, 5, and 6 may form a nucleoprotein in the virion, and VP3 may serve as an intermediate structural component.
TL;DR: The increased sensitivity of the modified method permits simultaneous determinations of other cell constituents as, for example, protein and DNA content of the same monolayer culture of fibroblasts, thus allowing for more meaningful studies on the mechanism of collagen biosynthesis in the tissue culture system.
TL;DR: The presence of traits that are present in the apes and probably related to functions of the hand in suspension of the body, fist-walking, and knuckle-walking in man implies that human ancestors similarly used the hand to suspend the body in the trees and to support it on the back of the flexed fingers.
Abstract: A means of determining the phylogenetic implications of similarities between the hands of man and non-human primates is proposed. The only traits shared by man and non-human primates accepted as evidence of our ancestral hand structure and functions are those which are incompatible or out of keeping with current behavior of the human hand. They may be assumed to remain only as relics of adaptations to former habits of locomotion and feeding. The relics found through this analysis are all traits that are present in the apes (some of them only in African apes) and probably related to functions of the hand in suspension of the body, fist-walking, and knuckle-walking. The presence of these traits in man implies that human ancestors similarly used the hand to suspend the body in the trees and to support it on the back of the flexed fingers.
TL;DR: Data suggest that in most subjects with hereditary angioneurotic edema, there is decreased synthesis of the C1 inhibitor but normal synthesis of C4, and that the disease results from this biosynthetic error.
Abstract: Although the Cl inhibitor was detected in 5 to 10 percent of normal hepatic parenchymal cells by means of the immunofluorescent technique, none was seen in liver biopsies from two individuals with hereditary angioneurotic edema having low concentrations of Cl inhibitor in the serum. In contrast, the percentages of cells which reacted with fluorescent antiserums to C4 and transferrin were normal. These data suggest that in most subjects with hereditary angioneurotic edema, there is decreased synthesis of the C1 inhibitor but normal synthesis of C4, and that the disease results from this biosynthetic error.