Showing papers by "Wayne State University published in 1981"

Lysosomal cathepsin B: correlation with metastatic potential.

Abstract: Although lysosomal enzymes are implicated in the processes of tumor invasion and metastasis, their cellular origin within the tumor is unclear. The activity of the lysosomal proteinase cathepsin B is significantly elevated in a variant of the B16 melanoma with high metastatic potential. The cathepsin B activity is localized to the lysosomes of the tumor cells.

Prostacyclin: a potent antimetastatic agent.

Abstract: Metastasis is the principal cause of failures to cure human cancers. Prostacyclin is a powerful antimetastatic agent against B16 amelanotic melanoma cells. This effect, which may result from the platelet antiaggregatory action of prostacyclin, is potentiated by a phosphodiesterase inhibitor. Inhibitors of prostacyclin synthesis increase metastasis. Prostacyclin and agents that may increase endogenous prostacyclin production or prolong its activity are suggested as new antimetastatic agents.

Combined therapy for cancer of the anal canal.

Abstract: Nineteen patients with squamous-cell cancer of the anal canal have been treated with combined chemotherapy and radiation therapy, followed by appropriate surgery. The authors are convinced that the combined therapy is effective enough to avoid abdominoperineal resection if disappearance of the lesion is proven by adequate examination and biopsy. Although they believe cancers 5 cm or less in maximum diameter are generally adequately managed in this manner, experience is still too limited to justify, a recommendation, to change currently accepted management.

Incidence of diurnal and nocturnal bruxism.

Abstract: P revious epidemiologic studies on the incidence of Table I. Incidence of bruxism bruxism have typically attempted to determine the rate of bruxism in a number of populations. These studies have differed in the age of the sample (child versus adult) and the status of the subjects (dental patients versus student or general populations). As a result, the reported incidence of bruxism has shown substantial variability. Among adults, for example, the rate of bruxism has been reported to be from 5.1% to 22.1%.‘-” Among children, reported incidence ranges from 11.6% to 15.1%.‘. ‘. ’ As might be expected, incidence rates for dental patients are typically higher than those reported for the general population.” With few exceptions, incidence studies of bruxism have attempted to determine only the relative rates of bruxism. While this information may have important public health and education implications, a finer level of analysis would provide information on incidence rates and would be potentially useful in the study of the etiology of the disorders. Such an analysis might identify subpopulations of bruxists who would, in turn, benefit from differing treatment modalities. Identification of these subpopulations might also help stabilize reported incidence rates in future research. Prior research’ has suggested that bruxists may be divided into two categories: (1) nocturnal (“nonstrain”) grinders and (2) diurnal (“strain”) clenchers. Nocturnal grinders are “true” bruxists who grind rather than clench. They grind nocturnally, independent of psychologic stress, and have a higher incidence of bruxism in relatives. Diurnal clenchers, on the other hand, clench rather than grind. They clench during the day, in response to stress, and have a low rate of bruxism among family members. While a number of the hypotheses of Olkinu-

Influence of environment on the floral sex ratio of monoecious plants.

Abstract: Both theoretical and empirical data suggest that sessile, simultaneous hermaphroditic individuals growing in patchy environments may experience unequal reproductive success via male and female gametes depending on whether they occupy favorable or marginal sites (Schaffner, 1935; Heslop-Harrison, 1972; Freeman et al., 1976, 1980; Charnov and Bull, 1977; Horovitz, 1978; Charnov, 1979a, 1979b; Willson, 1979). Under such conditions, differential tendencies toward maleness and femaleness should be selected for among individuals confined to favorable or unfavorable patches. Further, simultaneously hermaphroditic individuals should display large variations in the sex ratio of flowers on different individuals (Willson, 1979). Such variation might be expected to be controlled by both genetic and environmental cues, if the patches are small and/or the quality of any given patch varies significantly between breeding seasons (Heslop-Harrison, 1972; Freeman et al. 1976; Charnov and Bull, 1977; Frankel and Galun, 1977; Willson, 1979). In 1975, we began a series of studies to determine if the sex ratios of dioecious species differed on sites of differing water availability. We demonstrated that, in five dioecious species, males were proportionately more abundant on xeric sites than on mesic sites, while the females were over-represented on mesic sites (Freeman et al., 1976). Others have made similar observations (Pickett, 1915; Davey and Gibson, 1917; Schaffner, 1922; Lysova and Khizhnyak, 1975; Richards, 1975). We proposed that this pattern was due to disruptive selection acting on the differential success of male and female gametes on sites of differing quality. It seems likely that such forces may have been important in the evolution of the dioecious habit, at least in arid environments. Since disruptive selection appeared to alter the relative success of the male and female functions of dioecious species occupying a local array of sites that differed in the amount of available soil moisture during much of the growing season, it seemed likely that monoecious plants would also differentially emphasize maleness and femaleness on sites of unequal quality. In this note we examine the floral sex ratios of three monoecious species, and how these ratios differ on sites of differing water availability. Since our data (unpubl.) show that most temperate monoecious species are wind pollinated, we have restricted our studies to wind pollinated species.

Measurements of total scattering cross sections for intermediate-energy positrons and electrons colliding with helium, neon, and argon

Abstract: Total scattering cross sections have been measured in the same apparatus for positrons and electrons colliding with helium, neon, and argon atoms in the energy range from 15 to 800 eV using a beam-transmission technique. These measurements reveal a merging of the positron and electron cross-section curves for helium at energies above 200 eV while the available theories predict this merging to occur at considerably higher energies. For neon and argon the positron and electron total-cross-section curves are slowly approaching each other at the highest energies. The present experimental approach is analyzed with regard to the discrimination against small-angle forward elastic scattering, and estimates are made of other potential errors in the measured total cross sections. The present results are used to test the zero-energy sum rule, obtained from forward dispersion relations, and it is found that these data are consistent with prior measurements in that the sum rule is found to fail for electron scattering and to be valid for positron scattering.

Complex-coordinate calculations for doubly excited states of two-electron atoms

Abstract: Doubly excited states of helium sequence ($Z=1\ensuremath{-}10$) are investigated by a complex-coordinate method. Some lower-lying $^{1}S^{e}$ and $^{1,3}P^{o}$ states below the $N=2$ hydrogenic thresholds are calculated by the use of Hylleraas-type wave functions. Results are compared with recent calculations and experiments.

Multiple code activation in word recognition: evidence from rhyme monitoring.

Abstract: Seidenberg and Tanenhaus reported that orthographically similar rhymes were detected more rapidly than dissimilar rhymes in a rhyme monitoring task with auditory stimulus presentation. The present experiments investigated the hypothesis that these results were due to a rhyme production-frequency bias in favor of similar rhymes that was present in their materials. In three experiments, subjects monitored short word lists for the word that rhymed with a cue presented prior to each list. All stimuli were presented auditorily. Cue-target rhyme production frequency was equated for orthographically similar and dissimilar rhymes. Similar rhymes were detected more rapidly in all three experiments, indicating that orthographic information was accessed in auditory word recognition. The results suggest that multiple codes are automatically accessed in word recognition. This entails a reinterpretation of phonological "recording" in visual word recognition.

The phrenic nucleus of the albino rat: A correlative HRP and Golgi study

Abstract: The phrenic nucleus of the adult albino rat was studied by utilizing the O-dianisidine method for the retrograde transport of horseradish peroxidase in conjunction with the zinc chromate modification of the Golgi technique. Application of HRP to the transected phrenic nerve in the neck labeled a column of phrenic motor neurons from C3 to C5 in the ipsilateral spinal cord. However, when HRP was applied to the phrenic nerve intrathoracically, labeled neurons were found from C3 to C6. The long axis of the column of phrenic neurons was oriented tangentially from rostral to caudal poles. There was a gradual shift of the column from posterior to anterior and from lateral to medial positions in the ventral horn. The peroxidase material was also used to localize impregnated phrenic motor neurons in the Golgi sections and to provide quantitative data on phrenic motor neurons. In Golgi-impregnated material two types of phrenic neurons were distinguished on the basis of dendritic morphology and orientation. These neurons were designated (1) large neurons with smooth, radially oriented dendrites, and (2) smaller neurons with varicose, tangentially oriented dendrites. Both types of neurons had a small number of spines and bulbous appendages issuing from the dendritic trunks and branches. The dendritic fields of adjacent phrenic neurons overlapped extensively with one another and with dendrites of more distally placed ventral horn motor neurons. In peroxidase-labeled sagittal sections the dendrites of phrenic neurons were primarily oriented in the rostrocaudal plane. The mean total number of peroxidase-labeled neurons in the phrenic nucleus was 415.75 +/- 18.36 cells. In sagittal sections the mean long axis diameter of phrenic cell bodies was 34.5 micrometers. In frontal sections the mean long axis diameter of phrenic cell bodies was 22.5 micrometers. Thus, from direct measurement, the phrenic neurons were 34% longer in the sagittal plane than in the frontal plane. In the present study each phrenic nucleus contributed fibers only to the ipsilateral phrenic nerve, and no evidence for peripheral crossing of fibers was found.

The practicality of chronic hepatic artery infusion therapy of primary and metastatic hepatic malignancies: Ten-year results of 124 patients in a prospective protocol

Abstract: Ten-year results are presented of 124 patients with malignancy apparently limited to the distribution of the hepatic artery, treated to prospective protocol with continuous infusion of 5-FUdR through an hepatic artery catheter. Nearly all patients had moderate to massive hepatic replacement. Of 88 patients with colorectal carcinoma, 64 (73%) had clinically objective and subjective remission. Median survival for responders was 13 months; for the entire group, ten months. Of 13 patients with hepatoma, nine had clinically significant regression with a median survival of 11 months. Ten patients had carcinoma of the gall bladder or bile duct with seven obtaining clinically significant regression. Complications encountered are discussed and are similar to other series. Of the patients experiencing clinically significant remission, all but one reached the complete independence performance status, and 84% reached normal activity levels. Thus, for hepatic localized tumor, this therapy is worthwhile and practical.

An Examination of the Organizational Antecedents of Stressors at Work

Abstract: This paper identifies seven sources of stress in the work environment and examines the relationship of contextual, task, and role-related variables to such stressors. Both the type and magnitude of...

Proton-Linked Transport in Chromaffin Granules1

Abstract: Publisher Summary This chapter focuses on proton-linked transport in chromaffin granules. The function of the chromaffin granule is to store catecholamine in high concentration and, upon stimulation of the chromaffin cell, to deliver the catecholamine into the extracellular space by exocytosis. Chromaffin granules isolated from the adrenal medulla are a mixture of two populations, one containing epinephrine and the other containing norepinephrine. The chromaffin-granule adenosine triphosphatase hydrolyzes ATP on the external face of the membrane and translocates protons into the granule. The proton-linked transport system provides a good mechanism for achieving high concentration gradients without wasting energy in pumping catecholamines back and forth across the membrane. Because the catecholamine gradients are essentially in equilibrium with the pH gradient and membrane potential, catecholamines may exchange across the membrane with no energy consumption. Although norepinephrine will tend to stay in the granules, a continuous flux of norepinephrine into the cytoplasm will occur as long as norepinephrine in the cytoplasm is efficiently converted to epinephrine. Studies of catecholamine metabolism in chromaffin granules have benefited immeasurably from techniques and concepts of bioenergetics

T‐Cell Regulation in Autoimmune Thyroiditis

Abstract: The mechanisms of induction and maintenance of self-tolerance are still problematical. Several basically different strategies have been proposed to explain the body's apparent refusal to respond immunologically to its own constituents. 1. Self-reactive lymphocytes may be eliminated by clonal deletion during fetal life, by later clonal abortion or anergy, by receptor blockade or by other antigen-dependent methods of inducing and maintaining unresponsiveness. 2. Active immunoregulatory procedures, similar to those that normally limit immunological responses, may prevent autoimmunity by suppression. The leading candidates as active regulatory mechanisms are the generation of a distinct subpopulation of suppressor T lymphocytes, the production of specific anti-idiotypic antibodies or a combination thereof; that is, induction of antiiodiotypic cytotoxic T lymphocytes (Fig. 1). 3. Both clonal deletion and active suppression may be involved, providing double insurance against self-destruction by immunological means. The decisive question for distinguishing the several mechanisms of selfrecognition is whether lymphocytes that recognize unaltered self-antigens persist in normal animals. Clonal deletion theories in all of their various forms predict that they do not, whereas the concept of active regulation implies the persistence of functional, self-reactive lymhocytes in normal as well as disease states. To study this question we have been analyzing two different models of autoimmune thyroiditis. The first is experimental autoimmune thyroiditis

Syngeneic thyroglobulin is immunogenic in good responder mice

Abstract: Mouse thyroglobulin (MTg) or thyroid extract (TE) was given repeatedly to good responder C3H/Anf (H-2k) and poor responder BALB/c (H-2d) mice in the absence of adjuvant. Anti-MTg antibodies reached high levels in good responder mice given high doses of thyroid antigen. To eliminate stimulation by alloantigenic determinants and reduce the chance of denaturation, TE from syngeneic mice was prepared freshly each week and injected into good and poor responder strains. Again, significant antibody titers were observed in good responder mice. The antibody was specific for MTg since (a) it was not inhibited by extracts of other organs and (b) it reacted strongly with the closely related rat Tg and weakly with Tg from other species. Histology revealed mononuclear cell infiltration of the thyroid of good responder, but not of poor responder mice, regardless of the strain used to provide the thyroid antigen. The data demonstrate the presence of both T and B cell populations reactive with this self antigen and their stimulation by repeated high doses of antigen, without the aid of adjuvant, to override the regulatory controls that normally prevent autoimmune responses.

Intervention strategies to improve compliance with medical regimens by ambulatory hemodialysis patients

Abstract: This research examined the relative efficacies of three intervention strategies designed to increase compliance to medical regimens in a group of ambulatory hemodialysis patients. The interventions examined included behavioral contracting (with or without the involvement of a family member or friend) and weekly telephone contacts with patients. Compliance was assessed with regard to following dietary restrictions and limiting fluid intake. Data were collected from 116 patients drawn from two outpatient clinics. Within clinics, patients were randomly assigned either to an intervention program or to a control group. The study employed a pretest-posttest control group design. Patients were interviewed before the intervention programs began (T1), after a 6-week intervention period (T2), and 3 months after completion of the intervention period (T3). Results showed that the interventions achieved substantial reductions in patients' serum potassium levels and in weight gains between dialysis treatments between T1 and T2. In general, however, these program effects tapered off to preintervention levels between T2 and T3. The findings thus indicate a need for long-term intervention programs.