Showing papers by "Boston University published in 1977"

Neurogenesis in the adult rat: electron microscopic analysis of light radioautographs

Abstract: Three-month-old rats were injected intraperitoneally with [3H]thymidine (4.3 microcuries per gram of body weight) and allowed to survive for 30 days. Radioautography of 1-micrometer sections revealed labeled cells in the granular layers of dentate gyrus and olfactory bulb; these were confirmed as neurons by electron microscopy of reembedded 1-micrometer sections.

The framingham eye study i. outline and major prevalence findings

Abstract: During the period 1973--1975, 2675 out of 3977 still-living members of the Framingham, Massachusetts, study population, who have been under investigation for coronary disease risk factors since 1948 and who were in 1973--1975 aged 52 to 85, were given an eye examination stressing cataract, diabetic retinopathy, macular degeneration and glaucoma. Of 2940 subjects who still lived in the local Framingham area, 2477 were examined. Local population prevalence for one or both eyes positive was: 15.5% for senile cataract, 3.1% for diabetic retinopathy, 8.8% for senile macular degeneration and 3.3% for open-angle glaucoma. The proportion of adults with poor "best" visual acuity may be much less than has been estimated by the National Health Survey and the proportion with open-angle glaucoma much more than currently suspected on the basis of foreign studies.

A measure of interpersonal dependency

Abstract: Interpersonal dependency refers to a complex of thoughts, beliefs, feelings, and behaviors revolving around needs to associate closely with valued other people Its conceptual sources include the psychoanalytic theory of object relations, social learning theories of dependency, and the ethological theory of attachment A review of existing self-report inventories revealed none that adequately assessed interpersonal dependency A new 48-item self-report inventory which assesses interpersonal dependency in adults was developed, using a sample of 220 normals and 180 psychiatric patients It was cross-validated on two additional samples Three components of interpersonal dependency emerged: emotional reliance on another person, lack of social self-confidence, and assertion of autonomy The relationship of these components with normals and patients was discussed, as well as with the concepts of attachment and dependency

A new procedure for examining Golgi impregnated neurons by light and electron microscopy.

Abstract: A procedure is described by which neurons impregnated by the rapid Golgi method can be de-impregnated and their fine structure studied in the electron microscope. Brains are fixed by perfusion with buffered solutions containing formaldehyde and glutaraldehyde, and pieces are then impregnated by a rapid Golgi method. Sections, 150–200 μm thick, are cut from the impregnated blocks and immersed in glycerol so that sections containing suitably impregnated neurons can be selected under the light microscope. Such sections are immersed in gold chloride followed by oxalic acid. The original impregnation deposit of silver chromate is then removed with sodium thiosulphate. This process of de-impregnation leaves the originally impregnated neurons still visible in the light microscope for they now contain a deposit of gold. In the electron microscope this deposit is apparent as fine particles that mark the profiles of the de-impregnated neurons, but the deposit is such that it does not interfere with the fine structure which is remarkably well preserved. Thus, the cytological details of the de-impregnated neurons can be discerned and their synaptic relationships can be determined.

The Framingham Eye Study. II. Association of ophthalmic pathology with single variables previously measured in the Framingham Heart Study.

Abstract: Using the age-sex-specific data collected in the Framingham Heart Study 1948--1964 together with ophthalmic diagnoses made in the Framingham Eye Study in 1973--1975, the following variables were found to be associated with senile cataract: education, casual blood sugar, systemic blood pressure, height, vital capacity, serum phospholipid and hand strength; with senile macular degeneration: systemic blood pressure, height, vital capacity, left ventricular hypertrophy, hand strength and history of lung infection; with diabetic retinopathy: casual blood sugar, urine sugar and other specific elements of diabetes; with ocular hypertension: systemic blood pressure, height, casual blood sugar and pulse rate. No variables were identified as associated with open-angle glaucoma. The paper stresses the need for corroboration of these findings, which may be a mix of real and chance associations, and the need for additional analyses before any of these associations are considered evidence of factors related to risk of ophthalmic disease.

Cluster shapes at the percolation threshold: and effective cluster dimensionality and its connection with critical-point exponents

Abstract: An effective dimensionality dp is introduced for the purpose of providing a quantitative characterisation of the degree of ramification of the clusters that occur at the percolation threshold. It is found that dp is directly related to percolation critical exponents, and that 1

Aging of the rat olfactory bulb: Growth and atrophy of constituent layers and changes in size and number of mitral cells

Abstract: A quantitative study of the rat olfactory bulb during aging was carried out by directly measuring or calculating the following parameters at 3, 12, 24, 27, and 30 months: The volume of the glomerular, external plexiform, and internal granular layers, a relative measure of the size of the olfactory nerve layer, the mean volume of mitral cell nuclei and perikarya, a relative measure of the mean volume of the mitral cell dendritic tree as well as the total length and mean cross-sectional area of its constituent dendrites, and number of mitral cells. In addition, measurements of the size and number of mitral cells in the accessory olfactory bulb were performed. Data were analyzed with analysis of variance, multiple range tests for differences means at the various ages, and simple, partial, and multiple product-moment correlations. From 3 to 24 months a linear increase of approximately 50% occurs in all layers of the olfactory bulb. During this time the mean perikaryal volume and dendritic volume of mitral cells increases, also in a linear fashion, approximately 100%. No significant change occurs in the number of mitral cells. From 24 to 30 months a significant decrease occurs in the volume of the layers. Although the total volume of mitral cell dendritic trees decreases slightly from 24 to 27 months, the volume of individual mitral cell dendritic treess, as well as perikaryal and nuclear size, increases sharply during this period, apparently in compensation for a sharp decrease in the number of mitral cells which occurs at this time. From 27 to 30 months no further decrease in mitral cell number occurs, but the size of mitral cell perikarya, and especially dendritic trees, decreases sharply. The coordinated increase in olfactory bulb size from 3 to 24 months appears to be a comtinuation into adult life of earlier postnatal increases. The atrophy from 24 to 30 months appears not to be associated with peripheral rhinitis, since the glomerular and olfactory nerve layers do not show greater atrophy than the other layers, and atrophy also occurs in the accessory olfactory bulb, which is supplied by nerves from the vomeronasal organ, a structure not normally subject to rhinitis.

Afferent and efferent projections of the region in mouse SmL cortex which contains the posteromedial barrel subfield.

Abstract: Experiments using anterograde and retrograde tracing techniques have been used to identify projections to and from the region of mouse SmI cortex which contains the posteromedial barrel subfield (PMBSF, Woolsey and Van der Loos, '70). Microinjections containing horseradish peroxidase (HRP) and tritiated amino acids were placed unilaterally into the topographic center of the PMBSF. Brains were perfuse-fixed and frozen sectioned. All sections were reacted for HRP and alternate sections were autoradiographed. Examination of sections cut tangential to the pial surface in the region of the injection site showed that diffusion of the injection was limited to cortex above and below the PMBSF in layer IV (i.e., PMBSF cortex). A “column” of HRP reaction product and developed silver grains was present in ipsilateral cortical area 40, in the face area of SmII. HRP positive cell bodies were mainly in layer III and VI of this “column.” A similar “column” was present in ipsilateral cortical area 6, in a region which in the rat corresponds to the vibrissal area of MsI (Hall and Lindholm, '74), but here HRF positive cells bodies were situated mainly in layer V. HRP labeled cells bodies were also present in layer V of ipsilateral cortical area 29c. The ipsilateral nucleus ventralis thalami pars lateralis and the nucleus posterior thalami contained many HRP positive cell bodies and were associated with dense aggregations of developed silver grains. Numerous silver grains were also present over portions of the ipsilateral caudate, reticular nucleus of the thalamus and ventral pontine nuclei, but no HRP positive cell bodies occurred in these regions. HRP-filled axons left the injection site and traveled via the corpus callosum to contralateral PMBSF cortex where HRF labeled cell bodies were present mainly in layers III and V. Usually only one or two labeled somata were located superficial or deep to a contralateral PMBSF barrel. A few HRF positive cell bodies were also present in layers II and III of contralateral pyriform cortex. These results indicate that PMBSF cortex is reciprocally connected with ipsilateral cortical areas 6 and 40 and with the ipsilateral ventral and posterior nuclei of the thalamus. A small, homotopic callosal connection with contralateral PMBSF cortex has been demonstrated, and it is presumed that this projection is also reciprocal. PMBSF cortex projects to, but receives no projections from the ipsilateral caudate, reticular nucleus of the thalamus and the ventral pontine nuclei. Thus, many of the same projections of primary somatosensory cortex in higher animals, such as the monkey have been shown to occur in the mouse.

A Shift Of The Mean Level In A Sequence Of Independent Normal Random Variables—A Bayesian Approach—

Abstract: In this article, a study is made about a shift in the mean of a set of independent normal random variables with unknown common variance. The marginal and joint posterior distributions of the unknown time point and the amount of shift are derived. Small and large sample results are presented.

The Female Register: An Empirical Study of Lakoff's Hypotheses.

Abstract: Sociolinguists (e.g. Swacker 1975) and anthropologists (e.g. Hall 1959) are increasingly aware of the fact that sex, like social class or subcultural group, is a variable which strongly affects speech (Thorne & Henley 1975). While sexexclusive differentiation (i.e. separate male and female languages) now appears to be an almost nonexistent phenomenon, sex-preferred differentiation seems to be widespread across a number of languages and language families (Bodine 1975). In particular, recent studies indicate that syntax (Labov 1966), intonation (Brend 1972), and pronunciation(Trudgill 1972) in spoken English all vary as a function of the sex of the speaker.

The Origins of Social Skills and Interaction among Playgroup Toddlers.

Abstract: MUELLER, EDWARD, and BRENNER, JEFFREY. The Origins of Social Skills and Interaction among Playgroup Toddlers. CHILD DEVELOPMENT, 1977, 48, 854-861. A short-term longitudinal design permitted assessment of the growth of toddler social interaction in playgroups. The study analyzed social interaction sequences as well as the behavioral components of social interaction. In both playgroups the amount of peer interaction increased in significant linear fashion. Acquainted toddlers more frequently engaged in sustained social interactions than did less acquainted age-mates. They also utilized more coordinated social behaviors in their interactions. In the environment studied here, peer social relations originated during object-focused contacts. It was concluded that parallel play, rather than merely reflecting an inadequacy of early peer relations, represents a natural facilitating context for such relations. Participation in peer social interaction was itself responsible for the increase in skilled behavior among peer-experienced toddlers. Social interaction was seen as a source of growing social skill and not only its product.

Morphine lowering of self-stimulation thresholds: lack of tolerance with long-term administration.

Abstract: Rats were given increasing amounts of morphine over a period of weeks in order to achieve tolerance. Doses of the drug which initially reduced the threshold for self-stimulation behavior continued to do so after long-term administration. These results demonstrate a persistent central effect of morphine which may be related to the opiate "high."

The Costs of Major Wars: The Phoenix Factor

Abstract: A major unexplored area in the field of international politics is the consequences of major war for members of the international system in terms of power lost or gained. This paper explores these shifts of power among neutrals, winners, and losers as a result of these wars, using a sample of 32 cases and time series analysis. The findings register unexpected but systematic patterns after major conflicts; while winners and neutrals are affected marginally by the conflict, losers' powers are at first eroded. Over the long run (15–20 years), though, the effects of the loss dissipate; losers accelerate their recovery and soon resume antebellum status. It is this phenomenon that the authors call the phoenix factor.

Polyunsaturated fat, cholesterol and large bowel tumorigenesis.

Abstract: The possibility that the disposition of cholesterol, which is influenced by the quality of dietary fat, may be associated with either vascular lipidosis or colon cancer was evaluated in this study. Rats were fed diets containing cholesterol plus a) saturated fat, 20% coconut oil, to elevate serum cholesterol and promote vascular lipidosis or b) polyunsaturated fat, 20% safflower oil, to minimize serum cholesterol elevations and retard the development of vascular lipidosis. The relationships of these diets to gastrointestinal tract tumors induced by 1,2,-dimethylydrazine (DMH) was evaluated. Serum cholesterol levels in rats fed the coconut oil diet and given DMH were markedly elevated and were associated with moderate to severe vascular and aortic sudanophilia. Conversely, rats fed the safflower oil diet and given DMH had modest elevations in serum cholesterol levels and minimal vascular and aortic sudanophilia. Significantly, greater numbers of large bowel tumors induced by DMH were found in rats fed the safflower oil diet than in those fed the coconut oil diet. It was suggested that the polyunsaturated fat diet promoted the decrease in serum cholesterol levels concomitant with an increase in fecal neutral and acid sterols, which in turn augmented tumorigenesis by DMH in these animals compared with those fed the saturated fat diet. Thus, in the animal model used, the interaction of dietary fat (quality or quantity) with endogenous or dietary cholesterol determines whether or not diet will be a contributing factor in a) the development of vascular lipidosis or b) augmentation of small and large bowel tumorigenesis.

Azorean Disease of the Nervous System

Abstract: We studied a family of Portuguese ancestry from the Azores who suffered a progressive neurologic disease characterized by gait ataxia, features similar to Parkinson's disease in some patients, limitation of eye movements, widespread fasciculations of muscles, loss of reflexes in the lower limbs, followed by nystagmus, mild cerebellar tremor and extensor plantar responses. Two post-mortem examinations revealed loss of neurons and gliosis in the substantia nigra, nuclei pontis (and in the putamen in one case) as well as in the nuclei of the vestibular and other cranial nerves, columns of Clarke and anterior horns, in the spinal cord there were also loss of fibers in the fasciculi gracilis and mild changes in the pyramidal tracts. Comparison of the disease in this family with the findings reported in three families of similar ancestry, previously thought to have different disorders, suggests that they may all represent a single genetic entity with variable expression.

Symptomatic myocardial infarction without chest pain: prevalence and clinical course.

Abstract: Symptomatic myocardial infarction without chest pain was identified in 26 of 102 patients (25.5%) admitted to the hospital with acute myocardial infarction. As a group, these patients had a significantly lesser prevalence of a history of angina (P less than 0.05) and cigarette smoking (P less than 0.01). Their mean age was 69.1 years compared with 58.7 years for patients with chest pain (P less than 0.001). The group had a significantly greater median delay between the onset of symptoms and (1) arrival at the hospital (P less than 0.05), (2) examination by a physician in the emergency room (P less than 0.05), (3) diagnosis of possible myocardial infarction (P less than 0.001), and (4) transfer from the emergency room to the intensive care unit (P less than 0.001). They had significantly higher admission values for mean heart rate, respiratory rate, temperature and white blood cell count and more frequent in-hospital complications of pneumonia (P less than 0.001) and cardiogenic shock (P less than 0.05). Mortality in the group was 50% compared with 18% in the group with chest pain (P less than 0.05). Discriminant function analysis identified an at-risk population with 80% reliability.

Age‐related deterioration of pyramidal cell basal dendrites in rat auditory cortex

Abstract: The basal dendritic trees of layer V pyramidal cells in the rat auditory cortex were examined quantitatively in a group of 3-month-old and a group of 34- and 36-month-old rats. Two forms of analysis were used on the Golgi preparations: (1) the number of intersections between the basal dendrites and a series of concentric circles whose common center lies over the perikaryon center, and (2) the number of dendritic branches, by order, per neuron. The data indicate that in the old animals the density of the dendritic tree has decreased significantly within a radius of about 150mu of the perikaryon, yet the extent of the dendritic domain has not changed appreciably. Analysis of the dendritic branching suggests that there has been a deterioration not only in the peripheral branches of the dendritic tree, but also that entire dendrites have been lost. This loss of primary branches was confirmed through the reconstruction of layer V neuronal perikarya and their proximal dendrites from 1-mu plastic serial sections of auditory cortex. Concomitant with the loss of dendrites which accompanies advancing age is a tendency for the perikaryon to be smaller, but not distorted, in the old animals.

Degraded and Deskilled: The Proletarianization of Clerical Work

Abstract: The changing conditions of clerical work in several types of large and small organizations are examined. The analysis is based on observations in organizations, discussions with managers and intensive interviews with thirty clerical workers. Proletarianization is said to occur as clerical work loses the features that have traditionally placed it among middle-class, white collar occupations; as narrow, largely manual skills displace complex skills and mental activity; as close external control narrows the range of worker discretion; and as impersonal relationships replace social give and take. The extent of proletarianization varies among organizations. The larger organizations are leading the changes by developing technologies and organizational techniques for proletarianized clerical work. In the conclusion it is argued that structural changes promoting proletarianization may seriously impair the very efficiency that the changes are claimed to promote.

A refinement analysis of the crystallography of the phospholipid, 1,2-dilauroyl-DL-phosphatidylethanolamine, and some remarks on lipid—lipid and lipid-protein interactions

Abstract: A least-squares refinement analysis of atomic positional and thermal parameters in a single crystal of 1,2-dilauroyl-DL-phosphatidylethanolamine: acetic acid has been based on the X-ray diffraction intensities of 1132 independent reflexions, assessed by automatic microdensitometry. The final unweighted discrepancy index is 0.16 with e.s.ds of the bond lengths ranging from 0.02 to 0.12 A. The general features of our earlier, lessprecise analysis are confirmed. The close-packed arrangement of the phospholipid molecules is discussed in relation to electron microscopy and diffraction studies of the structures of membranes from Acholeplasma laidlawii and Halobacterium halobium.