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1
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Ultrastructural studies of experimental scrapie and Creutzfeldt-Jakob disease in hamsters. I. Alterations of myelinated axons

100%
Liberski P. P., Bratosiewicz-Wasik J., Gajdusek D. C., Brown P.
Acta Neurobiologiae Experimentalis
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2002
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vol. 62
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issue 3
121-129
EN
Classical and ultrastructural neuropathology of prion diseases are generally well described. Here we report that alterations of myelinated fibres in hamsters infected either with polioencephalopathic strains of scrapie or panencephalopathic strains of CJD (Echigo-1) are virtually identical and differ only quantitatively. In contrast, mice infected with the panencephalopathic Fujisaki strain of CJD exhibited much more elaborate changes of myelinated fibres.
2
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Ultrastructural studies of experimental scrapie and Creutzfeldt-Jakob disease in hamsters. II. Astrocytic and macrophage reaction toward the axonal destruction

100%
Liberski P. P., Bratosiewicz-Wasik J., Gajdusek D. C., Brown P.
Acta Neurobiologiae Experimentalis
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2002
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vol. 62
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issue 3
131-139
EN
We report here the microglial (macrophage) and astrocytic reaction in several models of transmissible spongiform encephalopathies (TSEs) or prion diseases. With the low power electron microscopy it was readily apparent that myelinated vacuoles were surrounded by cells and their processes. The latter belonged either to hyperplastic reactive astrocytes or to macrophages. Typically reactive astrocytes exhibited cytoplasm filled with innumerable glial filaments and, occasionally, other organelles (like cilia) and abundant tortuous intercellular junctions of adhesive plaque junction type. Desmosome-like junctions connecting astrocytic elements were also seen. As described earlier, astrocytic processes were occasionally interdigitated with oligodendroglial cells and their processes. Two types of macrophages were readily described. The majority of them exhibited electron-dense cytoplasm and numerous ?empty? vacuoles (digestive chambers) containing cellular debris. Occasional vacuoles were surrounded by a thin collar reminiscent of ?lyre-like inclusions? of the second type of macrophages. The latter were rare and characterized by numerous ?lyre-like? inclusions. Several mylinated fibres were clearly engulfed by the cytoplasm of a macrophage containing unusual annulate lamellae.
3

Ultrastructure of haemocytes present during flight muscle differentiation of Melipona quadrifasciata anthidioides, Lepidoptera (Hymenoptera, Apidae, Meliponinae)

100%
Da_Cruz-Landim C.
Folia Biologica
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1996
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vol. 44
79-84
EN
The present work deals with the ultrastructure of the haemocytes present in the dorsal thoracic region of larvae and pre-pupae of Melipona quadrifasciata anthidioides. This is a region of intense muscular differentiation in this phase of life of the insect. Only plasmatocytes, granulocytes, and adipohaemocytes were found in this area, all showing signs of being intermediate forms
4

Effects of Bacillus thuringiensis kurstaki on malpighian tubule cells of Thaumetopoea pityocampa (Lepidoptera: Thaumetopoeidae) larvae

100%
Ogutcu A., Suludere Z., Uzunhisarcikli M., Kalender Y.
Folia Biologica
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2005
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vol. 53
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issue 1-2
7-11
EN
In this study effects of Bacillus thuringiensis kurstaki (Btk) on Malpighian tubule cells of Thaumetopoea pityocampa (Lepidoptera: Thaumetopoeidae) larvae was investigated by electron microscopy. 3 mg/l Btk was given with food. After Btk administration, the Malpighian tubule cells were investigated and compared with a control group. 3 and 6 hrs after Btk administration swelling in Malpighian tubule cells was observed. Swelling of mitochondria and separation of their cristae was seen after 12 hrs. After 24 hrs dissolution of the basal cytoplasm, swelling and vacuolization of all mitochondria, partial dissolution of the nucleoplasm, and swelling and separation of microvilli was documented. A membrane-body in the nucleus was seen after 48 hrs. The nucleoplasm was completely dissolved after 72 hrs and after 96 hrs large vacuoles appeared in the cytoplasm and shortening of microvilli was observed.
5

Structure of the ovary and the differentiation of follicular epithelium in the pig louse, Haematopinus suis (Insecta: Phthiraptera)

100%
Zelazowska M.
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EN
The female reproductive system of the pig louse, Haematopinus suis (Insecta: Phthiraptera) is composed of paired ovaries, lateral oviducts, and a common oviduct that leads into a vagina. Clusters of mycetocytes (= cells filled with symbiotic organisms) are associated with lateral oviducts. Each ovary is composed of five loosely arranged ovarioles of the polytrophic-meroistic type. An individual ovariole is covered by a basal lamina and is composed of a terminal filament, germarium, and vitellarium. The terminal filament is composed of large, disc-shaped cells that are orientated perpendicularly to the long axis of the ovariole. The basal part of the terminal filament is separated from the germarium by a well-developed transverse septum. The germarium is short and filled with clusters of oogonial cells. In each cluster the cells are joined by intercellular bridges, filled with fusomal material. Within the cluster, only one cell, the future oocyte, enters the prophase of the first meiotic division; the other cells differentiate into nurse cells. The basal part of the germarium is filled with the somatic prefollicular cells. The boundary between the germarium and the vitellarium is not distinct. The vitellarium contains linearly arranged ovarian follicles in subsequent stages of oogenesis (previtellogenesis, vitellogenesis and choriogenesis). Each follicle consists of an oocyte and 7 nurse cells and is surrounded by follicular cells. During oogenesis the follicular cells diversify, so that ultimately, five morphologically distinct subpopulations of these cells can be distinguished: (1) cells in contact with the nurse cells, (2) anterior cells, (3) mainbody cells, (4) posterior cells, and (5) interfollicular cells. Interestingly, the follicular cells associated with the anterior part of the oocyte, i.e. located in space at the oocyte/nurse cell border (fold cells) are mitotically active throughout previtellogenesis. It might be suggested, in this context, that the separation of the oocyte from the nurse cell compartment is brought about by mitotic divisions, consequent multiplication and centripetal migration of these cells.
6

A study of the anatomy, histology and ultrastructure of the digestive tract of Orthrias angorae Steindachner, 1897

88%
Suicmez M., Ulus E.
Folia Biologica
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2005
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vol. 53
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issue 1-2
95-100
EN
The anatomy, histology and ultrastructure of the digestive tract of Orthrias angorae (Steindachner, 1897) were investigated using light microscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The histological structure consists of four layers: mucosa, submucosa, muscularis and serosa. The esophageal mucosa consists of undifferentiated basal epithelial cells, mucous cells and surface epithelial cells. It was observed that the J-shaped stomach had a meshwork of folds in the cardiac region, and longitudinal folds in the fundic and pyloric regions. A single layer of columnar cells, PAS positive only in their apical portions, forms the epithelium. The convoluted tube-shape intestine is lined by simple columnar epithelial cells, which have microvilli at the apical surface. The wall of the esophagus and stomach are thicker than that of the intestine because of the thick muscle layer. There were numerous goblet cells in the intestine. There were numerous gastric glands in the submucosa layer of the cardiac stomach, but none were present in the pyloric region of the stomach. There were no pyloric caeca between the stomach and intestine. The enterocytes with microvilli contained rough endoplasmic reticulum, ribosomes and rounded bodies, and the gastric cells contained a well-developed Golgi apparatus.
7

Do germ-line cells in Allacma fusca (Insecta, Collembola, Symphypleona) have a higher metabolic rate than somatic cells

88%
Swiatek P., Klag J., Romek M.
Folia Biologica
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2001
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vol. 49
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issue 1-2
85-90
EN
Stereological analysis of the ultrastructure of primordial germ cells (PGCs) and the somatic (ectoderm) cells in two developmental stages of embryos and freshly hatched juveniles of Allacma fusca have shown great differences in mitochondria volume density (vd) between the two types of cells. In younger embryos (migration phase of the PGCs) the vd of mitochondria in the cytoplasm of the PGCs is 74.64% higher than in the ectoderm cells. In older embryos, (PGCs in the gonads) the vd of mitochondria is 123% higher than the corresponding value for the somatic cells cytoplasm. In the juvenile the vd of mitochondria in the ectoderm cells grows twice but is still only 2/3 of the value for the PGCs. On the basis of papers describing a direct relationship between stereological and physiological results the authors conclude that the metabolism of the primordial germ cells during embryonic development of Allacma fusca is much higher than that of the somatic ones. If the above conclusion is correct, the results presented here confirm the ?disposable soma theory? (Kirkwood & Holliday 1979).
8

The ovary of Neotituria kongosana (Hemiptera, Cicadomorpha: Ledridae). Ultrastructure of the tropharium and terminal filamen

88%
Lupa B., Kim J.-K., Bilinski S. M.
Folia Biologica
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1999
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vol. 47
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issue 3-4
123-130
EN
Each of the 2 ovaries of Neotituria kongosana consists of 7 telotrophic ovarioles. Within the ovariole, the terminal filament, germarium, vitellarium, and pedicel can be distinguished. The terminal filaments are composed of disc-shaped basal cells and elongated apical cells, oriented parallel to the long ovariole axis. The apical and lateral aspects of the tropharium are encompassed by a single layer of somatic cells termed inner sheath cells. These cells are diversified into larger apical inner sheath cells (AISC) and much smaller lateral inner sheath cells (LISC). The tropharium is filled with numerous individual trophocytes (= nurse cells). All the trophocytes are surrounded by complete plasma membranes and are joined to a centrally located trophic core by means of narrow cytoplasmic extensions, termed trophic processes. The terminal filament is separated from the rest of the ovariole by a relatively solid transverse septum. It is suggested that the material constituting the septum is synthesized by 2 types of cell, namely the AISC and the basal cells of the terminal filament. Anagenesis of hemipteran ovarioles is discussed in relation to the findings presented.
9

Effects of Thaumetopoea pityocampa (Lepidoptera: Thaumetopoeidae) larvae on the degranulation of dermal mast cells in mice; an electron microscopic study

88%
Kalender Y., Kalender S., Uzunhisarcikli M., Ogutcu A., Acikgoz F.
Folia Biologica
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2004
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vol. 52
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issue 1-2
13-17
EN
The pine caterpillar Thaumetopoea pityocampa (Lepidoptera: Thaumetopoeidae) is found in pine woods. Hairs of the T. pityocampa caterpillar cause a cutaneous reaction in humans and animals. Mast cells are responsible for allergic reactions in mammals. In this study male swiss albino mice were divided into two groups: 5 mice in the control group and 25 mice in the experimental group. The dorsal skin of mice was shaved. The mice in the experimental group and T. pityocampa larvae (fifth instar, approximately n=100) were put in the same cage. Dermal mast cells of mice exposed to T. pityocampa were examined with a transmission electron microscope and compared to the control group 1, 3, 6, 12 and 24 hours after exposure. Dermal mast cell degranulation in mice was observed 12 and 24 hours after exposure.
10

The structure of the airbladder of the catfish Pangasius hypophthalmus Roberts and Vidthayanon 1991 (previously P. sutchi Fowler 1937)

88%
Podkowa D., Goniakowska-Witalinska L.
Folia Biologica
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1998
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vol. 46
189-196
EN
The catfish Pangasius hypophthalmus from South-Eastern Asia uses the airbladder as an accessory respiratory organ. The airbladder is situated at the dorsal part of the body cavity and is connected with the esophagus by a short pneumatic duct lined with mucus cells. The histological and ultrastructural study reveals that the wall of the airbladder is composed of three layers: the outer layer of serosa membrane, the middle one of connective tissue with many collagen fibres, and the inner layer - the simple respiratory epithelium. The medium and inner layers form numerous septa protruding into the lumen of the airbladder. The central septum divides the airbladder longitudinally into two chambers. The respiratory epithelium consists of a single type of flat cells covering a dense capillary network. Ciliated and mucus cells are absent. Epithelial cells possess long and thin microvilli on their surface. Their cytoplasm contains a large nucleus, the Golgi apparatus, rough endoplasmic reticulum, mitochondria, and a few electron-dense and lamellar bodies accumulating surfactant. The air-blood barrier is composed of epithelium, connective tissue, and endothelium with a thickness ranging from 0.2 to 2.4 mum.
11

Cytochemical identification of mucocysts in Balantidium coli trophozoites

88%
Skotarczak B.
Folia Biologica
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1999
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vol. 47
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issue 1-2
61-65
EN
The mucocyst ultrastructure in B. coli has not been described so far. As demonstrated in this work, cytoenzymatic assays on B. coli with the use of a reaction-detecting membrane-coupled hydrolase, i.e., ATP-ase, permitted identification of the mucocysts in the ciliate studied. The shape, size, and location of mucocysts in B. coli trophozoites were found to correspond to descriptions of these structures in other ciliates. The mucocysts were more numerous in B. coli trophozoites isolated from the symptomatic balantidiosis-affected pigs (Group I), and the product of reaction to ATP-ase was more copious than in Group II trophozoites. However, not all the bubble-like structures with similar morphological features reacted positively to the enzyme. The discrepancy was explained by the cytoenzymatic reaction to Beta-GR. The reaction product was visible in the vesicular structures, situated above the plasmolemma, although some of them contained no reaction product. Thus the presence of two types of secretory structure can be inferred: the mucocysts, with ATP-ase in their membranes, and other extrusomes containing active Beta-GR.
12

Ultrastructural studies of the ovary of Palaeococcus fuscipennis (Burmeister) (Insecta, Hemiptera, Coccinea: Monophlebidae)

88%
Szklarzewicz T., Kedra K., Niznik S.
Folia Biologica
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2005
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vol. 53
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issue 1-2
45-50
EN
Ovaries of Palaeocoocus fuscipennis are composed of about 100 telotrophic ovarioles that are devoid of terminal filaments. In the ovariole a tropharium (=trophic chamber) and vitellarium can be distinguished. The tropharium contains 7 trophocytes. A single oocyte develops in the vitellarium. The oocyte is surrounded by follicular cells that do not undergo diversification into subpopulations. The obtained results are discussed in a phylogenetic context.
13

Primary ciliary dyskinesia: genes, candidate genes and chromosomal regions

88%
Geremek M., Witt M.
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issue 3
347-361
EN
Primary ciliary dyskinesia (PCD) is a multisystem disease characterized by recurrent respiratory tract infections, sinusitis, bronchiectasis and male subfertility, associated in about 50% patients with situs inversus totalis (the Kartagener syndrome). The disease phenotype is caused by ultrastructural defects of respiratory cilia and sperm tails. PCD is a heterogenetic disorder, usually inherited as an autosomal recessive trait. So far, mutations in two human genes have been proved to cause the disease. However, the pathogenetics of most PCD cases remains unsolved. In this review, the disease pathomechanism is discussed along with the genes that are or may be involved in the pathogenesis of primary ciliary dyskinesia and the Kartagener syndrome.
14

Structure and development of ovaries in the weevil, Anthonomus pomorum (Coleoptera, Polyphaga). I. Somatic tissues of the trophic chamber

88%
Swiatek P.
Folia Biologica
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2001
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vol. 49
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issue 3-4
215-224
EN
In developing ovarioles of Anthonomus pomorum (Coleoptera, Polyphaga, Curculionidae) the trophic chambers (tropharia) are relatively large and consist of clusters (clones) of germ cells and various somatic tissues. Each ovariole is enclosed within an outer epithelial sheath (tunica externa). Throughout the pupal phase, the growth of this sheath is accelerated and precedes the development of the rest of the ovariole. As a result, the epithelial sheath proliferates anteriorly and forms an elongated ?sleeve? that during the later stages of development becomes gradually filled by the growing tropharium. In the early pupal stage, a few terminal filament cells are observed in contact with the anterior end of the tropharium. These cells are separated from the rest of the trophic chamber by a transverse septum, which maintains continuity with the basal lamina. Beneath the basal lamina there is a layer of inner sheath cells, whereas inside the tropharium there are interstitial cells. These two types of cell differ morphologically in a mature ovary but they retain, until the end of the imago-B stage, a similar ultrastructure testifying to their common origin. At the posterior end of the tropharium, from the imago-B stage on, many young oocytes, surrounded by prefollicular cells, are observed. This is the so-called neck region of the tropharium. Extraction with Triton X-100 detergent showed that in a mature trophic chamber there are only individual microtubules arranged along the projections of interstitial cells. This indicates that the cytoskeleton elements (microfilaments and microtubules) participate only to a very limited extent in the spatial organisation of the tropharium in A. pomorum.
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