Search results for "Ultrastructure"

Zur Ultrastruktur der Kerneinschl�sse von Bindegewebszellen im Psoriasisherd

1975

In 6 Hautproben von Psoriasis-Herden werden elektronenoptisch nach Kontrastierung mit Uranylacetat und Bleicitrat stark vermehrt Einschluskorper im Nucleoplasma von Bindegewebszellen nachgewiesen. Diese Spharidien enthalten Glycogen und Lipoide. Die Befunde, die fur eine Aktivierung des Bindegewebs-Zellstoffwechsels sprechen, werden im Zusammenhang mit den bereits vorhandenen Hinweisen auf eine Beteiligung des Bindegewebes, vielleicht im Sinne einer “unspezifischen Mesenchymreaktion”, bei der Psoriasis erortert.

Cardiac lysosomes in doxorubicin cardiotoxicity: An ultrastructural study

1988

A light and electron microscope study of spherical structures in the test cells of an ascidianCiona intestinalis L.

1984

Spherical structures in the test cells that surround the embryos of the ascidianCiona intestinalis L. (Tunicata, phylum Chordata) were studied by both light and electron microscope. Our data support the view that these structures are microorganism-like cells living in symbiosis with the test cells. Their possible role is discussed.

Microcinematographic Studies of Mycoplasma hominis Cells

1973

Cells of two strains of Mycoplasma hominis growing in liquid medium on a glass surface were observed continuously, and cinematographic pictures were taken. Most of the observed structures showed reversible changes of their shape, suggesting the presence of contractile material in membrane or cytoplasma. The frequency and speed of such variations were measured. The deformations seem to be related to multiplication. The mechanisms of these phenomena are unknown.

The response ofAsterochloris erici(Ahmadjian) Skaloud et Peksa to desiccation: a proteomic approach

2013

The study of desiccation tolerance of lichens, and of their chlorobionts in particular, has frequently focused on the anti- oxidant system that protects the cell against photo-oxidative stress during dehydration/rehydration cycles. In this study, we used proteomic and transcript analyses to assess the changes associated with desiccation in the isolated phycobiont Aste- rochloris erici. Algae were dried either slowly (5-6 h) or rapidly (<60 min), and rehydrated after 24 h in the desiccated state. To identify proteins that accumulated during the drying or rehydration processes, we employed two-dimensional (2D) difference gel electrophoresis (DIGE) coupled with individual protein identificatio…

Ultrastructural Studies on Development in Mature Seeds; Embryos ofEuonymus europaeaL. Dormant or Cultured at +25 °C

1989

Ultrastructural observations on naturally dispersed and dehydrated seeds of Euonymus europaea L. were performed. It was shown that during the culture of isolated embryos at 25 °C for 7 d the maturation of protein bodies continued; the initial juvenile form (single protein body per cell with dispersed contents) was developing into a more advanced form (single body split to form several sub-units with condensed contents). Parallel biochemical determinations pointed to an increase in insoluble protein levels. There were no changes in other storage organelles, lipid bodies, either in the fine structure or in the level of triacylglycerols. Deterioration of cellular membranes (in mitochondria, pr…

A cytological and ultrastructural study on the maturation and germination of oospores of Plasmopara viticola from overwintering vine leaves.

1999

Observations on cytological and ultrastructural changes in Plasmopara viticola oospores were carried out during the overwintering period. Three types of oospores were observed. Type I, characterized by a thin inner oospore wall (IOW), large lipid globules and two nuclei, was recovered only in samples collected in October. These oospores were considered to be immature. Maturation occurred during November and involved a noticeable increase in thickness of the IOW, fusion of nuclei, formation of an ooplast and break up of large lipid globules into smaller ones (type II oospores). A few oospores (type III) showed abnormal organization with very large lipid globules and less frequently discernib…

Death of mitochondria during programmed cell death of leaf mesophyll cells

2005

The role of plant mitochondria in the programmed cell death (PCD) is widely discussed. However, spectrum and sequence of mitochondrial structural changes during different types of PCD in leaves are poorly described. Pea, cucumber and rye plants were grown under controlled growing conditions. A part of them were sprinkled with ethylene releaser to accelerate cell death. During yellowing the palisade parenchyma mitochondria were attracted to nuclear envelope. Mitochondrial matrix became electron translucent. Mitochondria entered vacuole by invagination of tonoplast and formed multivesicular bodies. Ethephon treatment increased the frequency of sticking of mitochondria to the nuclear envelope …

Respiratory epithelium exposed to sulfur dioxide--functional and ultrastructural alterations.

1995

The value of morphological investigations of airway mucosa should be compared to a functional method when estimating the toxicity of airborne pollutants. In 34 guinea pig tracheas, mucociliary activity was measured using a modified light beam reflex method before and following exposure to sulfur dioxide for 30 minutes in concentrations ranging between 7.5 and 37.5 mg/m3. Exposure to air served as a control. Simultaneously, specimens were taken for light and electron microscopy. Mucociliary activity decreased from 8.4 +/- 2.9 Hz (control exposure) to 4.0 +/- 2.9 Hz following exposure to 7.5 mg/m3, to 3.4 +/- 2.7 Hz at 15 mg/m3 sulfur dioxide, to 1.8 +/- 2.2 Hz at 22.5 mg/m3 sulfur dioxide, t…

Human NCL Neuropathology

2015

AbstractThe neuronal ceroid lipofuscinoses (NCL) currently encompass fourteen genetically different forms, CLN1 to CLN14, but are all morphologically marked by loss of nerve cells, particularly in the cerebral and cerebellar cortices, and the cerebral and extracerebral formation of lipopigments. These lipopigments show distinct ultrastructural patterns, i.e., granular, curvilinear/rectilinear and fingerprint profiles. They contain−although to a different degree among the different CLN forms−subunit C of ATP synthase, saposins A and D, and beta-amyloid proteins. Extracerebral pathology, apart from lipopigment formation, which provides diagnostic information, is scant or non-existent. The ret…