Showing papers by "Icahn School of Medicine at Mount Sinai published in 1980"

Effect of harassment and competition upon cardiovascular and plasma catecholamine responses in type A and type B individuals.

Abstract: Two experiments examined the relationship between Type A behavior and cardiovascular and plasma catecholamine responses to experimental competition and harassment. Experiment I showed that, in 44 male adults, the presence of a hostile opponent caused no significant differences in the responses of Type B's. In A's, by contrast, hostility elicited greater increases in systolic blood pressure, heart rate and plasma epinephrine during competition. Behavior pattern A appears selectively predisposed to enhanced reaction to hostile interactions, but competition alone does not distinguish between individuals with A and B behavior patterns. Experiment II, with 20 cases, was carried out to determine whether or not the absence of A-B differences in the presence of a nonhostile competitor could be explained by Type B's reactivity to the challenge of competition alone. The results were consistent with this interpretation. A's showed greater blood pressure and plasma epinephrine evaluations than B's when both types were confronted by the challenge of task performance. Consideration was given to the role of sympathetic activation in mediating the tendency of Type A individuals to develop coronary heart disease.

The nosologic validity of paranoia (simple delusional disorder). A review.

Abstract: The diagnostic status of paranoia (renamed simple delusional disorder [SDD]) has been debated since the time of Kraepelin Three main views have emerged that consider paranoia (1) a subtype of schizophrenia, (2) a subtype of affective illness, or (3) a distinct nosologic entity The literature pertinent to the diagnostic validity of a SDD is examined Although the methodology of a number of the studies reviewed would not be considered rigorous by today's standards, certain tentative conclusions can nonetheless be reached The available data do not suggest that SDD is a subtype of affective illness The evidence reviewed also does not strongly support the hypothesis that SDD is a subtype of schizophrenia Although some of the data is consistent with the view that SDD is a "mild" form of schizophrenia, the bulk of the evidence suggests that SDD and schizophrenia are distinct syndromes

Hydrogen peroxide production by rat brain in vivo.

Abstract: H2 O2 production by rat brain in vivo was observed with a method based on the measurement of brain catalase. The administration to the rat of 3-amino-1, 2, 4-triazole, an H2 O2- dependent inhibitor of catalase, caused progressive inhibition of brain catalase activity in both the supernatant and pellet fractions of homogenates of the striatum and prefrontal cortex. The prevention of catalase inhibition by prior administration of ethanol confirmed that catalase inhibition in vivo was dependent upon H2 O2. A significant portion of the catalase (30-33%) appeared in the supernatant fraction from a slow-speed homogenization procedure and was not significantly contaminated by either erythrocytes or capillaries. In the whole homogenate, less than 6% of the catalase activity was attributed to erythrocytes. Modification of intracellular monoamine oxidase activity by either pargyline or reserpine did not change the rate of inhibition of catalase by aminotriazole. A probable interpretation of these data is that H2 O2 generated by mitochondrial monoamine oxidase does not reach the catalase compartment; the catalase is contained in particles described by other investigators as the microperoxisomes of brain. In studies in vitro, the production of H2 O2 by rat brain mitochondria with either dopamine or serotonin as substrate was confirmed.

ACTH, beta-lipotropin, and related peptides in brain, pituitary, and blood.

Abstract: Publisher Summary This chapter presents the demonstration of a precursor molecule containing adrenocorticotropic hormone (ACTH) and β -lipotropin in multiple tissues, which has the potential to be processed into products both similar to and different from those elaborated by the anterior and intermediate pituitary lobes This has raised a number of fundamental questions with regard to its biosynthetic pathways and regulation and to the functions of the peptide products The chapter discusses the nature and regulation of extrapituitary form of ACTH family of peptides and the forms secreted by human pituitary, both in normal subjects and in diseases characterized by disorders of ACTH regulation Both ACTH and β -lipotropin can serve as precursors for other biologically active peptides In humans, ACTH and β -melanotropin ( β -MSH) are secreted concomitantly and occur within the same cell of the anterior pituitary The distribution of ACTH and β -lipotropin cells is identical Within the arcuate nucleus, these cells in colchicine-treated rats are distributed throughout its rostrocaudal extent as for α -MSH in the vinblastine-treated rat The concept of a hypothalamic center distributing ACTH, α -MSH, or β -endorphin via axons to regulate many other brain regions is comparable to the oxytocin and vasopressin fibers in many extra hypothalamic sites that originate in the magnocellular paraventricular nucleus of the hypothalamus The ACTH- β -lipotropin and vasopressin-oxytocin systems are unique among known brain peptides as their perikarya is restricted to the hypothalamus The hypothalamus is the center of the ACTH- β -lipotropin brain

In Vitro Biosynthesis and Comparative Posttranslational Processing of Immunoreactive Precursor Corticotropin/β-Endorphin by Human Placental and Pituitary Cells*

Abstract: Normal human pituitary cells and human placental cells derived from the trophoblastic shell and adhering decidua incorporate [3H]lysine and [35S]methionine during a 30- min incubation period into high molecular weight glycoproteins containing the antigenic determinants of both ACTH and β- endorphin, demonstrating for the first time actual placental synthesis of such material and synthesis by the human pituitary. Such high molecular weight ACTH/β-endorphin was resolved into at least two molecular species upon sodium dodecyl sulfate polyacrylamide gel electrophoresis, with apparent molecular weights of 34,000 ± 2,600 and 46,000 ± 3,900. These high molecular weight glycoproteins were retained on a Concanavalin-A column and were eluted with excess D-mannose but not with synthetic ACTH or β-endorphin. Partial tryptic mapping of high molecular weight material revealed two fragments physicochemically similar to ACTH-(9-15) and β-endorphin-(l–9) [Mipotropin-(61–69)]. Additional immunoreactive species of lower mol...

Cortical binocularity in infants

Abstract: The primate visual cortex, including that of man, receives separate input from each eye and these interact in binocular cortical neurones. This organization is known to be vulnerable to disruption in early life. To understand the development of human visual cortex, and to detect and assess disorders of binocular function at the earliest possible age, a robust method is needed for detecting binocular interactions in the infant's visual system. We have done this by recording cortical visual evoked responses (VERs) to the onset and offset of binocular correlation in a large-screen dynamic random dot display. We report here that, in general, the human infant has a functional binocular visual cortex by 3 months of age, with some individuals showing cortical binocularity at an earlier age.

Traumatic dislocations of the first metatarsophalangeal joint.

Abstract: The mechanics, anatomy, and pathomechanics of traumatic dorsal dislocation of the first metatarsophalangeal joint are discussed. There are two basic types of dislocations. In Type I, dislocation of the hallux with the sesamoids occurs without disrupting the sesamoid mass. Such cases are usually irreducible on closed reduction, the metatarsal head being incarcerated by the conjoined tendons with their intact sesamoids. In Type II, there is either associated disruption of the intersesamoid ligament (Type IIA) or a transverse fracture of one of the sesamoids (Type IIB). In Type II, the sesamoid disruption usually permits closed reduction.

Glutamate dehydrogenase deficiency in three patients with spinocerebellar syndrome

Abstract: Four nicotinamide-adenine dinucleotide phosphate-requiring enzymes were measured in disrupted cultured skin fibroblasts from a 19-year-old patient with juvenile onset of a spinocerebellar and extrapyramidal syndrome. There was marked reduction in the activity of glutamate dehydrogenase (GDH) (22% of mean control activity); GDH activity was also decreased in homogenates of leukocytes from this patient (38% of mean control activity). GDH activity was measured in the leukocytes of two siblings afflicted with adult-onset spinocerebellar syndrome and found to be decreased in both (29% and 31% of mean control activity); an unaffected sibling had normal GDH activity. Mixing experiments with control fibroblast and leukocyte homogenates did not show the presence of a GDH inhibitor in cells from these patients. This allosterically regulated enzyme was stimulated by adenosine 5′-diphosphate (10−3 M) and inhibited by guanosine 5′-triphosphate (10−3 M) in both fibroblast and leukocyte homogenates; these changes occurred in equal proportions in the patients and controls. The decreased fibroblast and leukocyte GDH activity persisted at different concentrations of the enzyme's substrates and with successive passages of cultured fibroblasts. GDH may have an important role in the metabolism of glutamate, a putative neurotransmitter in cerebellum, brainstem, and spinal cord. A genetic deficiency of GDH may underlie some forms of spinocerebellar ataxias.

Complete nucleotide sequence of the influenza A/PR/8/34 virus NS gene and comparison with the NS genes of the A/Udorn/72 and A/FPV/Rostock/34 strains

Abstract: The nucleotide sequence of the NS gene of the human influenza virus A/PR/8/34 was determined and found to be the same length (890 nucleotides) as the NS gene of another human influenza virus A/Udorn/72 and of the avian isolate A/FPV/Rostock/34. Comparison of the sequences of the NS genes of the two human influenza viruses shows an 8.9% difference whereas the NS gene of the avian isolate differs by only 8% from that of the human strain A/PR/8/34. The extensive sequence similarity among these three genes does not support the notion of species specific homology groups among NS genes of avian and human influenza virus strains. The primary sequence of the A/PR/8/34 NS gene is consistent with the findings that the influenza virus NS gene may code for two overlapping polypeptides. In addition, an open reading frame potentially coding for a polypeptide 167 amino acids in length was found in the negative strand RNA of the A/PR/8/34 virus NS gene.

Some suggested revisions concerning early female development.

Abstract: The tentative and culturally biased early formulations of female sexual development by the founder of psychoanalysis, Sigmund Freud, are well publicized and are often popularly thought to be THE psychoanalytic theory of female development. They are criticized both for confusing the consequences of cultural pressure with innate feminine disposition and for giving scientific validation and enhancement to those cultural pressures. There is, however, more to be said both about Freud and about psychoanalytic theories of feminine development. Freud, for all his patriarchial Viennese Victorian biases and his phallocentrism, took women’s sexual life seriously. He learned psychoanalysis from listening to women patients, acknowledged and deplored the repressive forces operating against women’s full development, and provided a treatment that supported women’s efforts to free themselves from repressive forces (rather than the other current treatmerits by surgical means, which ranged from removing the offending organ, “the hyster” or uterus, to clitoridectomy, to dictatorial and imprisoning “rest cures”, to coercive morality).

Lateralization of reward in rats: differences in reinforcing thresholds.

Abstract: Fourteen rats with bilaterally implanted lateral hypothalamic electrodes were allowed to self-stimulate each side of the brain during daily test sessions. Rotation (circling behavior) during self-stimulation sessions was also recorded. All rats rotated in preferential direction regardless of the side of the brain stimulated, and, in each case, the direction was the same as that subsequently determined in response to d-amphetamine. All rats had asymmetries in self-stimulation thresholds related to the direction of rotation. Thresholds were lower on the side contralateral to the direction of rotation, and entire rate-intensity functions were displaced to the left on that side. The results, discussed in terms of lateralization of affect, suggest a model in which quantitative differences in neuronal firing can be translated into apparent qualitative specialization, with the two sides of the brain appearing to be specialized for high and low mood, respectively.

Regional Distribution of Glutathione Peroxidase in the Adult Rat Brain

Abstract: Glutathione peroxidase activity was measured in 10 areas of perfused adult rat brain with the use of a fluorometric assay coupled to NADPH oxidation. The caudate-putamen and the substantia nigra had the highest activities. Cortical areas and several nuclear areas had somewhat lower activity. Activity was lowest in a white matter structure (corpus callosum). High activity of glutathione peroxidase may be related to the need to reduce hydrogen peroxide arising in the course of monoamine metabolism.

Bilateral basal ganglia calcifications visualised on CT scan.

Abstract: Thirty-eight cases of basal ganglia calcification imaged on computed axial tomography were reviewed. Most cases were felt to represent senescent calcification. The possibility of a vascular aetiology in this group is discussed. A less common group of patients was identified with calcification secondary to abnormalities in calcium metabolism or radiation therapy. Three cases of basal ganglia calcifications were detected in juvenile epileptic patients receiving chronic anticonvulsants. These cases may be related to abnormalities in calcium metabolism and alkaline phosphatase activity. Clinical evidence of basal ganglia abnormality was generally absent demonstrating the preservation of neuronal pathways in most cases.

Purification and Physicochemical Properties of Ricins and Agglutinins from Ricinus communis

Abstract: Two toxin ricins and two agglutinins have been purified from the seeds of Ricinus communis by an improved procedure based on ion-exchange chromatography and gel filtration. One of the two purified ricins binds to Sepharose 4B while the other does not. The physicochemical properties of the four Ricinus lectins are presented and the possible relationships of these Ricinus lectins to those previously described are discussed.

Ultrastructure of transplant glomerulopathy

Abstract: Thirty-one specimens of tissue were obtained from 15 renal allografts 3-96 months after transplantation and studied by light, electron and in some cases also by immunofluorescence microscopy. All patients had a degree of renal insufficiency and almost all had proteinuria and moderate hypertension; nephrotic syndrome was present in one and hematuria in two. On histological examination one patient showed cellular proliferation suggestive of glomerulonephritis (recurrent or de novo) and another patient had numerous crescents. The most frequent glomerular lesion was widening of the lamina rara interna with subendothelial accumulation of finely granular material, formation of new subendothelial basement membrane and deposition of microfibrils and fine filaments. The mesangial changes were mainly those of mesangiolysis and mesangial sclerosis with deposition of mesangial matrix and microfibrils, but little cellular proliferation. Fragmented red blood cells were seen in nearly half of the patients. In another seven patients the lesion resembled focal segmental glomerulosclerosis. This combination of changes termed transplant glomerulopathy leads to diffuse glomerular sclerosis. Arterial intimal thickening and occasionally also thrombosis produced ischaemic changes in the kidney and in the glomeruli and contributed significantly to the process of transplant rejection.