PubMed Health⌕ Search

Biomedical subjects

S Heyner

Publications and source records attributed to S Heyner.

At least 55 records · Page 3Linked to original sources
PubMed1987

Golgi study of the primate substantia nigra. I. Quantitative morphology and typology of nigral neurons.

Neuronal morphology was analyzed in the pars compacta, reticulata, and lateralis of the substantia nigra of humans and macaques. Golgi-impregnated dendritic arborizations, reconstructed from serial sections, were described by using topological, metrical, and geometrical parameters measured in three dimensions. Morphological parameters were statistically analyzed. Cell bodies and axons were also described. The primate substantia nigra comprises few local circuit microneurons. It consists mainly of large projection neurons having large cell bodies and sparsely branched dendritic arborizations. In all subdivisions, "complex endings" and "thin processes" can be found on nigral dendrites. Axons of large neurons occasionally had initial collaterals that never form profuse arborizations. Pars reticulata neurons had a cell body surface of 520 micron2, 4 dendritic stems, and 13 dendritic tips. The total dendritic length (L) was 7,100 micron, the highest dendritic length (Lm) 1,200 micron, and the mean length of dendritic segments 320 micron. Pars lateralis neurons were similar except for their larger cell bodies (650 micron2) and longer dendritic segments (440 micron). Pars compacta neurons had larger cell bodies (860 micron2), thicker and more numerous (5 stems, 19 tips), and longer dendrites (L = 10,500 micron; Lm = 1,400 micron). Large neurons of monkeys had the same topological characteristics as human neurons but shorter dendrites. The overall shape of arborizations was highly variable and not characteristic in any subdivision. A hierarchical typology of nigral neurons is proposed, which comprises two neuronal species, the compacta and reticulata species, and a lateralis subspecies. Pallidal neurons (Yelnik et al., '84) belong to the reticulata species. The position of these species in relation to higher hierarchical levels is discussed.

Animals↗
PubMed1987

Characteristics of cell lines derived from normal and malignant endometrial tissue.

Five established cell lines of human endometrium, two of normal endometrium and three of proven tumorigenicity, have been compared in terms of morphology and chromosomal numbers. Each of the five cell lines was then analyzed using immunocytochemical techniques to show that the epithelial and stromal elements could be separately identified. Antibodies directed against cytokeratin and desmoplakins were used to identify epithelial elements and antibodies directed against fibronectin were used as a marker for stroma. These results were then confirmed using Western blot analysis. We conclude that cell lines of human endometrium in culture can be differentiated as being of epithelial or stromal origin. Cell lines derived from reportedly normal human endometrium exhibit a stromal phenotype with a normal karyotype, whereas cells of tumorigenic human endometrial cell lines exhibit an epithelial phenotype and abnormal karyologic characteristics.

Adenocarcinoma↗
PubMed1987

Maternal humoral immune response to incompatibility at multiple minor histocompatibility loci in mice.

Mice of the H-2b haplotype were mated with males of the same MHC haplotype, but differing at multiple minor histocompatibility loci. Mice were bled during each pregnancy and at 2-day intervals post-partum. The sera were assayed by indirect immunofluorescence for evidence of a humoral immune response to paternal minor histocompatibility antigens. Alloantibody was first detected in the post-partum period following the third pregnancy, and was also detected during the fourth pregnancy. Thereafter, alloantibody levels dropped and by the post-partum period following the fifth pregnancy, fell to control values. Assays on a panel of cells from mice of different inbred strains revealed specificity of the alloantibody to H-3.1, H-4.1 and H-7.1 antigens. A conventional dye exclusion cytotoxicity test revealed the pregnancy-induced alloantibody did not exhibit complement-dependent cytotoxicity. These findings are discussed in relation to the regulation and functional significance of the humoral immune response in allogeneic pregnancy.

Animals↗
PubMed1986

Stage-specific insulin binding in mouse preimplantation embryos.

Stage-specific insulin binding in the developing mouse embryo was demonstrated by an indirect immunofluorescence technique using an antibody against insulin. Concentration-dependent fluorescence labeling was observed in the morula and blastocyst stages of development, whereas no reactivity was seen in unfertilized oocytes or in 2-, 4-, and 8-cell embryos. The possible significance of these observations is discussed. This represents the first report of stage-specific insulin binding during mammalian preimplantation development.

Animals↗
PubMed1986

Humoral and cellular immunologic aspects of adjuvant and collagen arthritis in rats.

Systemic and local immunological responses of rats sensitized with either M. butyricum or native type II collagen have been evaluated. In rats exhibiting adjuvant-induced arthritis no antibodies to collagen could be detected. In animals exhibiting collagen-induced arthritis, high antibody titers developed by day 14, and could be correlated with the severity of the arthritis. Delayed type hypersensitivity (DTH) responses were measured by a 5-iodo-2'-deoxyuridine 125-I (125-IUdR) uptake assay. Arthritic scores in rats immunized with collagen were not accompanied by a positive DTH response, whereas adjuvant arthritic rats showed a positive response. T-lymphocyte cellular responses in both adjuvant- and collagen-induced arthritic rats were measured. In neither syndrome were major alterations observed in T-lymphocyte subpopulations. These results provide evidence that adjuvant-induced arthritis and type II collagen-induced arthritis are distinct entities, and that they may be discriminated by the nature of the humoral response.

Animals↗
PubMed1985

A histological atlas of the macaque (Macaca mulatta) substantia nigra in ventricular coordinates.

An atlas of the macaque substantia nigra was established in ventricular coordinates. Having verified that nigral contours are stable in both Macaca mulatta and Macaca speciosa, the antero-posterior sequence of four subdivisions was described on eight vertico-transverse levels after a comparison between histological and histochemical data. The pars reticulata constitutes the anterior pole containing pale, small cell-bodies scattered among the numerous endings of the striato-pallido-nigral fibres. Anteriorly, the pars compacta forms the dorsal border of the substantia nigra, but more posteriorly, it leaves the dorsal border and develops ventral fringes. Its large cell-bodies, most often pigmented, rich in Nissl bodies and in acetylcholinesterase, are closely spaced among a few axonal fascicles. The pars lateralis contains a low density of cell-bodies and corresponds to the hilum of entrance of the striato-pallido-nigral fibres and gives rise to a nigro-tectal projection. The pars mixta, dorsally located, contains a low density of neurons varying considerably in size. It represents the hilum of exit of nigral axons which project to various targets.

Anatomy, Artistic↗
PubMed1984

A Golgi analysis of the primate globus pallidus. I. Inconstant processes of large neurons, other neuronal types, and afferent axons.

The present paper is a Golgi study, with high-power lenses, of the primate globus pallidus. Two kinds of inconstant processes of large neurons are first described: complex endings and thin processes. Complex endings are thick apparatuses terminally located on dendrites having many appendages of various types. Contacts were observed not only between striatal axons and these complex endings but also between complex endings and the soma, dendritic stems, dendritic portions or complex endings of other large pallidal neurons. Thin processes were usually beaded, very thin, and arose from any part of the dendritic tree. Contacts were seen between them and soma or dendrites of other large neurons. These thin processes were very similar to initial axonal collaterals and together constitute a common pool of processes. Complex endings and thin processes were essentially observed in the lateral nucleus of the pallidum where they apparently are evenly distributed inside the nucleus but randomly distributed on individual neurons. Two neuronal types other than large pallidal neurons were isolated: the smallest were considered to be local circuit neurons, while intermediate-sized neurons might be the origin of a particular efference. Many striatal axons gave no branches over long distances and collaterals were of two types and most frequently were short (less than 50 micron). Larger axonal arborization were rarely encountered. In addition to parallel contacts, numerous very short ones were observed. All these contacts between striatal axons and dendrites of large pallidal neurons seem to be irregularly distributed.

Afferent Pathways↗
PubMed1980

Application of a radiometric ear assay for studies of adjuvant arthritis in rats.

A radioisotopic method, originally developed for measuring the cellular response in delayed hypersensitivity lesions in mice, has been evaluated in adjuvant arthritic rats. Focal accumulation of 5-iodo-2'-deoxyuridine-125I (125IUdR) at a site of antigen challenge (left pinna) was measured and expressed as increased radioactivity in the challenged (left) over the unchallenged (right) ear (L/R ear ratio). Immunologic specificity of the assay was established with anti-lymphocyte globulin (ALG)-treated arthritic rats. ALG significantly inhibited the 125IUdR L/R ear ratio; normal rabbit globulin had no effect on this parameter. A significant negative correlation was observed between the 125IUdR ear ratios and subjective arthritic scores in established adjuvant disease. Certain characteristics of the 125IUdR radiometric ear assay in rats were established in several types of experiments: disappearance of the isotope from blood, whole body irradiation studies in turpentine-injected rats, and cyclophosphamide pretreatment in a sheep erythrocyte antigenic system. The results of this study support the utility of the 125IUdR ear assay to quantify cellular accumulation at a site of antigen challenge in adjuvant arthritic rats and possibly other antigenic systems in this species.

Animals↗
PubMed1980

Differential expression of minor histocompatibiility antigens on the surface of the mouse oocyte and preimplantation developmental stages.

The expression of specific minor histocompatibility antigens on oocytes and preimplantation developmental stages in the mouse has been examined using immunofluorescence. Multi-specific alloantisera in conjunction with serological adsorption and target cells of the appropriate genotype have been used to how that there is differential expression of minor histocompatibility antigens during early development. Detailed analysis showed that antigen expression can be detected on oocytes and zygotes, but not on two-cell stages. From the eight-cell stage to the blastocyst, reactivity with antibody directed against a single specificity could be detected.

Adsorption↗
PubMed1975

The presence of paternal H-2 antigens on hybrid mouse blastocysts during experimental delay of implantation and the disappearance of these antigens after onset of implantation.

The presence of paternal H-2 antigens on hybrid mouse blastocysts before and during implantation was investigated by means of the isotope anti-globulin technique. It was found that experimentally delayed blastocysts possess paternal H-2 antigens whereas these antigens can no longer be detected 14 hours after estradiol activation of delayed blastocysts.

Animals↗
PubMed1971

Differential immunofluorescence of fertilized mouse eggs with H-2 and non-H-2 antibody.

Mouse embryos at the two-cell and blastocyst stages, as well as unfertilized eggs, have been studied by indirect immunofluorescence for the expression of H-2 and non-H-2 histocompatibility antigens on surface membranes. Serologically-specific reactivity to non-H-2 antibody (H-3 and H-6) was observed as diffuse, patchy staining over the entire surface of the blastomeres at the two-cell stage. In contrast, no reactivity of two-cell or unfertilized egg embryos of four inbred strains was observed when antisera containing only multispecific H-2 cytolytic antibody were used. Antisera containing H-2 along with non-H-2 antibody of unknown specificity showed varying degrees of reactivity, which could be shown by absorption studies to be due to the non-H-2 content of the serum. The results suggest that the initial expression of histocompatibility genes varies and support the hypothesis that the appearance of these cell components may relate to specific stages of differentiation.

Animals↗