Acta histochemica. Supplementband最新文献

A review is presented of fine-structure autoradiographic [incorporation of (5-3H)uridine] and immunoelectron microscope (localization of small nuclear ribonucleoproteins--snRNPs) data on the onset of extranucleolar transcription in early preimplantation bovine embryo. First incorporation (5-3H) uridine into blastomere nuclei nucleoplasm occurs, in the early cow embryo, during the 8-cell stage. Both the degree of chromatin condensation as well as the intensity of labeling increase as the fourth cycle of the embryonic blastomeres progress. However, neither the level of extranucleolar chromatin condensation nor the degree of labeling usually detected in somatic cells have been observed during this stage but occurred only in later stages of embryo development. The association of the label with the periphery of the condensed chromatin demonstrates, as in other cell types the sites of newly synthesized hnRNA. A further insight into the functional microarchitectural changes of the early cow embryo nuclei in relation to the onset of transcription has been obtained by immunoelectron microscope studies on Lowicryl K4M embedded material. Using this technique, the pattern of the contrast in the preparations following uranyl/lead staining was comparable to that obtained by the Bernhard's (1969) regressive staining for preferential nuclear-RNP visualization. In this way, the coordinate appearance of perichromatin fibrils on the borderline of the already condensed chromatin was evident during the 8-cell stage. Especially in the "in vitro" produced embryos the condensed chromatin occurred in marked blocks with a clearly defined perichromatin region in the thin sections. In the same nuclear area Sm-antigen (associated with a group of snRNPs) has concentrated and localized to perichromatin fibrils.(ABSTRACT TRUNCATED AT 250 WORDS)

In situ hybridization histochemistry opened new perspectives for the study of viral infections of the central nervous system. Immunohistochemistry can give information about the presence of a viral infection only, if the specific viral proteins are expressed in the infected cells, while in situ hybridization can detect viral genes also in case of a latent, non-productive infection. The basic technique has to be modified according to the kind of viral nucleic acid to be displayed (genomic DNA, plus or minus strand genomic RNA, viral mRNA). For detection, the highly sensitive radioactive or the less sensitive non-radioactive (enzyme-) labels can be applied. For the determination of the cell type harbouring the virus and for correlation of viral nucleic acids with viral proteins, in situ hybridization techniques and immunohistochemistry have to be combined.

The differential diagnosis of Alzheimer's and so-called multi-infarct dementia is still a major problem in clinical dementia research. It was Binswanger who in 1894 pointed out that a subtype of vascular dementia exists which is characterized by subcortical arteriosclerotic encephalopathy. It is this type that can most easily be mistaken for Alzheimer's dementia, presented for the first time in 1906, which may be associated with congophilic angiopathy leading to brain infarction. Beyond clinical criteria, which in part are summarized in Hachinski's ischemic score, further advancement of brain imaging techniques, especially those yielding perfusion or metabolic data, has facilitated and substantiated clinical in vivo distinction.

Biopsies of right auricle of human heart have been obtained during open heart surgery from 6 patients aged 23 to 49. The DNA and total protein content have been determined in isolated myocytes by two-wavelength scanning cytophotometry after double staining: Feulgen and naphthol yellow S. In all the biopsies predominant are polyploid hypertrophied myocytes. Both hypertrophied non-degenerating cells and cells with different extent of degenerative changes, primarily of myofibrils and membranes, are present. The highest extent of cell ploidy is in patients belonging to functional class IV according to the classification of New York Heart Association (NYHA); in these cases 72 to 98% of cells have nuclei with 8 c and more DNA content. With an increase in ploidy level, cells grow in size and in protein content, however the rate of this growth is much lower than that of DNA content in cells. There is no direct relation between ploidy and cell degeneration extent and no inverse relation between degeneration extent and ejection fraction.

The arterial distensibility and the modulus of volume elasticity of more than 100 isolated human carotid arteries was measured and correlated with arteriosclerosis and aging. The loss of arterial distensibility progresses steadily with aging. Arteries with severe arteriosclerosis and arteries with minimal arteriosclerosis show almost similar distensibility. On the other side the differences between distensibility of arteries with moderate arteriosclerosis and arteries with minimal as well as severe arteriosclerosis, especially in the younger and middle ages, are significant.

Obduction of a woman aged 52 years, showed a diffuse primary leptomeningeal melanoblastosis with development of a malignant melanoma in adjacent region of brain parenchyma. Clinically it was misdiagnosed as a haematoma.

Parvalbumin and calbindin, two calcium binding proteins in the nervous system, are present in certain neuronal subpopulations. In the present study a method for a simultaneous demonstration of the both antigens was developed, which labels parvalbumin- and calbindin-containing structures in contrasting colours. A horseradish peroxidase-conjugated second antibody was used for the visualization of the monoclonal anticalbindin antibody, whereas the biotinylated anti-parvalbumin antibody was demonstrated by means of a biotin-streptavidine-alkaline phosphatase system. The method may be useful to classify neuronal populations and to study their morphological relationship.

The paper describes the value of immunohistologically estimated differences in the intermediate filament protein composition of the different cell types of human adenohypophysis and the corresponding pituitary adenomas. Interestingly, some tumors failed to express any type of intermediate filament proteins, whereas other coexpress cytokeratins and vimentin/or neurofilament protein.

Synaptophysin is a major integral membrane glycoprotein of neuronal synaptic vesicles that is present in virtually all synapses and shows a high degree of evolutionary conservation in mammalian species. It has also been detected in numerous endocrine cell types where it is localized in the membrane of small synaptic-like vesicles which are thought to constitute a previously unknown secretory pathway. Antibodies directed against synaptophysin are a valuable tool for the immunohistochemical quantitation of synapses. Moreover, synaptophysin is a most reliable and specific marker molecule for normal and neoplastic neuroendocrine cells. In the nervous system, synaptophysin-positive tumors comprise ganglioneuromas, ganglioneuroblastomas, neuroblastomas, paragangliomas and primitive neuroectodermal tumors.

Potentiated hippocampal synapses were found to be characterized by specific changes of the cytoskeleton in the postsynaptic spine. Aggregated bundles of actin filaments in the potentiated spines were revealed by decoration with myosin subfragment-1.