Ultrastructure of the digestive and protonephridial systems of the metacercaria of Euclinostomum multicaecum

1998 ◽  
Vol 72 (3) ◽  
pp. 243-249 ◽  
Author(s):  
P. Ramasamy ◽  
G.P. Brennan ◽  
K. Stalin
Keyword(s):  
Basal Lamina ◽  
Inclusion Bodies ◽  
Lipid Droplets ◽  
Spherical Inclusion ◽  
Muscle Fibres ◽  
Collecting Ducts ◽  
Parenchymal Cells ◽  
Dense Inclusion ◽  
Prolonged Feeding ◽  
Electron Dense Inclusion

AbstractThe structure of the digestive tract of Euclinostomum multicaecum (Digenea: Euclinostomatidae) is unusual, comprising several main lateral caeca which extend posteriorly and further divide, giving rise to numerous smaller branches which are widely distributed throughout the fluke. These multicaeca presumably promote nutrient absorption during rapid and prolonged feeding directly following excystment. The caecal wall consists of a syncytial gastrodermal epithelium, bearing loop-like lamellae which extend into the lumen and enclose spherical inclusion bodies and presumably also, increase the absorptive surface area. There was no evidence of endo- or exocytosis, nor were lysosomes, phagosomes or residual bodies observed. The gut caeca are supported by a fibrous basal lamina and an underlying layer of muscle fibres, while parenchymal cells occupy much of the extracellular space. The protonephridial system resembles that observed in other digeneans consisting of flame cells and collecting ducts which join to form a bladder that opens externally through a single excretory pore. The syncytial epithelium of the collecting ducts is elevated by numerous lamellae while the basal lamina is highly infolded. The luminal contents of these ducts comprise bar-shaped crystalline structures, lipid droplets and electron-dense inclusion bodies. The excretory system is supported by a network of muscle fibres and parenchymal cells.

A Strain of Pseudomonas aeruginosa Resistant to a Quaternary Ammonium Compound1

1976 ◽  
Vol 39 (8) ◽  
pp. 546-550
Author(s):  
C. J. WASHAM ◽  
W. E. SANDINE ◽  
P. R. ELLIKER
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Quaternary Ammonium ◽  
Inclusion Bodies ◽  
Light And Electron Microscopy ◽  
Quaternary Ammonium Compound ◽  
Ammonium Compound ◽  
Dense Inclusion ◽  
Yeast Extract Agar ◽  
Electron Dense Inclusion ◽  
Resistant Cells

Light and electron microscopy studies were made of Pseudomonas aeruginosa strains which were sensitive and resistant to a quaternary ammonium compound (QAC). The colonies of the sensitive cells on Tryptone Glucose Yeast Extract Agar were granular and homogeneous in consistency. In contrast, the colonies of the resistant strain on the same medium were granular, non-homogenous, and contained numerous dense areas. Morphological observations revealed the resistant cells to be 30% smaller than sensitive cells and non-motile due to loss of polar flagella, a characteristic which was not restored when the organisms were cultured in the absence of QAC for more than 7 months. Electron-dense inclusion bodies were present in resistant cells; they ranged in size from about 0.05 to 0.2 μm in diameter. These bodies, which were not identified, were released intact from lysing cells; as many as 20 per cell were visible.

A membrane-bound plastid inclusion in the epidermis of leaves of Taraxacum officinale

1977 ◽  
Vol 55 (2) ◽  
pp. 222-225 ◽  
Author(s):  
E. S. Martin ◽  
G. Larbalestier
Keyword(s):  
Inclusion Bodies ◽  
Functional Role ◽  
Taraxacum Officinale ◽  
Single Membrane ◽  
Membrane Bound ◽  
Dense Inclusion ◽  
Electron Dense Inclusion

Epidermal chloroplasts of Taraxacum officinale agg. contain large electron-dense inclusion bodies enclosed by a single membrane. These inclusion bodies were not observed in mesophyll chloroplasts. The origin and functional role of these structures is discussed.

Microprobe analysis of inclusion bodies related to two benzofuran derivatives

1987 ◽  
Vol 45 ◽  
pp. 672-673
Author(s):  
T. L. Benning ◽  
P. Ingram ◽  
J. D. Shelburne
Keyword(s):  
Inclusion Bodies ◽  
Uranyl Acetate ◽  
Multiple Organ ◽  
High Dose ◽  
En Bloc ◽  
Tissue Samples ◽  
Transmission Electron ◽  
Organ Systems ◽  
Dense Inclusion ◽  
Melanin Complex

Two benzofuran derivatives, chlorpromazine and amiodarone, are known to produce inclusion bodies in human tissues. Prolonged high dose chlorpromazine therapy causes hyperpigmentation of the skin with electron-dense inclusion bodies present in dermal histiocytes and endothelial cells ultrastructurally. The nature of the deposits is not known although a drug-melanin complex has been hypothesized. Amiodarone may also cause cutaneous hyperpigmentation and lamellar lysosomal inclusion bodies have been demonstrated within the cells of multiple organ systems. These lamellar bodies are believed to be the product of an amiodarone-induced phospholipid storage disorder. We performed transmission electron microscopy (TEM) and energy dispersive x-ray microanalysis (EDXA) on tissue samples from patients treated with these drugs, attempting to detect the sulfur atom of chlorpromazine and the iodine atom of amiodarone within their respective inclusion bodies.A skin biopsy from a patient with hyperpigmentation due to prolonged chlorpromazine therapy was fixed in 4% glutaraldehyde and processed without osmium tetroxide or en bloc uranyl acetate for Epon embedding.

scholarly journals Ultrastructural characteristics of the vascular wall components of ruptured atherosclerotic abdominal aortic aneurysm

2013 ◽  
Vol 65 (4) ◽  
pp. 1271-1278
Author(s):  
Irena Tanaskovic ◽  
Vesna Lackovic ◽  
D. Radak ◽  
Slavica Knezevic-Usaj ◽  
Milena Lackovic ◽  
...  
Keyword(s):  
Abdominal Aortic Aneurysm ◽  
Aortic Aneurysm ◽  
Basal Lamina ◽  
Lipid Droplets ◽  
Cell Populations ◽  
Abdominal Aortic ◽  
Extracellular Matrix Components ◽  
Ultrastructural Characteristics ◽  
Apoptosis And Necrosis ◽  
Synthetic Phenotype

The aim of this study was to determine the ultrastructural characteristics of cell populations and extracellular matrix components in the wall of ruptured atherosclerotic abdominal aortic aneurysm (AAA). We analyzed 20 samples of ruptured AAA. For orientation to the light microscopy, we used routine histochemical techniques by standard procedures. For ultrastructural analysis, we applied transmission electron microscopy (TEM). Our results have shown that ruptured AAA is characterized by the remains of an advanced atherosclerotic lesion in the intima followed by a complete absence of endothelial cells, the disruption of basal membrane and disruption of internal elastic lamina. On plaque margins as well as in the inner media we observed smooth muscle cells (SMCs) that posses a euchromatic nucleus, a well-developed granulated endoplasmic reticulum around the nucleus and reduced myofilaments. The remains of the ruptured lipid core were acellular in all samples; however, on the lateral sides of ruptured plaque we observed a presence of two types of foam cells (FCs), spindle- and star-shaped. Fusiform FCs possess a well-differentiated basal lamina, caveolae and electron dense bodies, followed by a small number of lipid droplets in the cytoplasm. Star-shaped FCs contain a large number of lipid droplets and do not possess basal lamina. On the inner margins of the plaque, we observed a large number of cells undergoing apoptosis and necrosis, extracellular lipid droplets as well as a large number of lymphocytes. The media was thinned out with disorganized elastic lamellas, while the adventitia exhibited leukocyte infiltration. The presented results suggest that atherosclerotic plaque in ruptured AAA contains vascular SMC synthetic phenotype and two different types of FCs: some were derived from monocyte/macrophage lineage, while others were derived from SMCs of synthetic phenotype. The striking plaque hypocellularity was the result of apoptosis and necrosis of different cell populations.

Growth and hepatic composition in the guinea pig after long-term parenteral hyperalimentation

1986 ◽  
Vol 251 (2) ◽  
pp. R388-R397 ◽  
Author(s):  
C. J. Lu ◽  
D. Redmond ◽  
R. B. Baggs ◽  
A. Schecter ◽  
T. A. Gasiewicz
Keyword(s):  
Guinea Pig ◽  
Lipid Droplets ◽  
Morphological Analysis ◽  
Basic Research ◽  
Serum Chemistry ◽  
Glycogen Accumulation ◽  
Catheter Implantation ◽  
Ad Libitum ◽  
Parenchymal Cells

This study examined the feasibility of maintaining male Hartley guinea pigs on long-term hyperalimentation. Data from animals fed ad libitum, but infused with 0.9% saline, indicated that there was minimal effect from catheter implantation, sepsis, or the infusion of large volumes of fluid. This group compared with animals fed and watered ad libitum demonstrated a nearly identical growth rate (6.33 +/- 1.18 and 6.12 +/- 1.32 g/day, respectively), serum chemistry, tissue weights, and hepatic composition and morphology. Animals infused with a total parenteral diet demonstrated growth rates of 4.06 +/- 1.46 g/day for up to 25 days. Loss of infused animals was due in varying degrees to sepsis, mechanical failure, improper placement of the cannula, loss of patency, and death from unknown causes. Morphological analysis of animals fed by total parenteral nutrition revealed an altered distribution and increased size of lipid droplets in hepatic parenchymal and Kupffer cells and glycogen accumulation by the parenchymal cells. Decreased hepatic content of total protein and lipid, as well as cytochrome P450, was also observed. Similarly, serum values of triglyceride were decreased in animals fed by the total parenteral diet. This study indicated that the guinea pig fed by hyperalimentation may be a useful animal model for a number of clinical and basic research applications.

The tegument and associated structures of Haplometra cylindracea

Parasitology ◽  
1968 ◽  
Vol 58 (1) ◽  
pp. 1-7 ◽  
Author(s):  
L. T. Threadgold
Keyword(s):  
Royal Society ◽  
Regional Differences ◽  
Lipid Droplets ◽  
Research Council ◽  
Science Research ◽  
Secretory Body ◽  
Dense Bodies ◽  
Research Associate ◽  
Parenchymal Cells ◽  
Science Research Council

The tegument of Haplometra cylindracea is protoplasmic. It is organized on two levels, a surface syncytium (‘cuticle’ of the light microscopists) and tegumental cells which lie among the parenchymal cells below the muscle layers. The surface syncytium and tegumental cells are joined together by protoplasmic, tube-like, processes.The surface syncytium is covered apically and basally by a unit plasma membrane. It contains mitochondria, vacuoles, lipid bodies, spines with a crystalline structure and dense secretory bodies. This syncytium lies on a basement membrane and a thick, fibrous, interstitial layer. The connecting protoplasmic processes, which originate from the base of the syncytium, are vacuolated and have few inclusions but, as they approach the tegumental cells, they become progressively filled with cytoplasm, cell inclusions and dense bodies.The tegumental cells consist of individual areas of nucleated protoplasm, usually lying in groups. These cells contain dense secretory bodies, mitochondria, a few lipid droplets, crystalline inclusions, and Golgi complexes. The Golgi complexes and granular endoplasmic reticulum are jointly involved in the production of a dense, probably proteinaceous, secretory body. Some qualitative regional differences in tegumental ultrastructure are described.The tegument of Haplometra is compared with that of other species so far described and like them must be considered both a protective and a secretory epithelium.I should like to express my sincere thanks to the following: The Wellcome Trust and Science Research Council for grants to purchase an Akashi TRS 50 and and A.E.I. EM6B electron microscope respectively; the Royal Society for a personal grant to purchase a Reichert Ultramicrotome and a vacuum coating unit; the Wellcome Trust for a grant to employ a Research Associate.

Network distribution of mitochondria and lipid droplets in human muscle fibres

2007 ◽  
Vol 129 (1) ◽  
pp. 65-72 ◽  
Author(s):  
Christopher S. Shaw ◽  
David A. Jones ◽  
Anton J. M. Wagenmakers
Keyword(s):  
Lipid Droplets ◽  
Human Muscle ◽  
Muscle Fibres

Acetylcholine receptors at the rat neuromuscular junction as revealed by deep etching

1982 ◽  
Vol 215 (1199) ◽  
pp. 147-154 ◽  
Keyword(s):  
Neuromuscular Junction ◽  
Basal Lamina ◽  
Acetylcholine Receptors ◽  
Postsynaptic Membrane ◽  
Muscle Fibres ◽  
Nerve Terminals ◽  
Single Muscle ◽  
Deep Etching ◽  
Collagenase Treatment ◽  
Regular Arrangement

Collagenase treatment of rat intercostal muscles yielded single muscle fibres in which the nerve terminals and basal lamina were removed allowing an unimpeded view of the ecternal surface of the postsynaptic membrane. This was revealed by deep etching of freeze-fractured preparations and appeared as a maze of folds separated by deep troughs, showing on the crests of the folds a densely packed population of protrusions about 8⋅5 nm in diameter. These densely packed protrusions ( ca . 9000 μm -2 ) are mainly confined to the postsynaptic regions of the sarcolemma and presumably represent the acetycholine receptor molecules, which are highly concenrated in these areas. The protrusions are generally tightly packed without obvious regular arrangement, but in some areas, usually on the tops of the crests, they are arranged into irregular rows normal to the long axis of the folds.

The effects of temporary ischaemia on rat muscle spindles

Development ◽  
1986 ◽  
Vol 92 (1) ◽  
pp. 223-254
Author(s):  
F. H. Diwan ◽  
Alice Milburn
Keyword(s):  
Basal Lamina ◽  
Satellite Cells ◽  
Muscle Spindles ◽  
Muscle Fibres ◽  
Nerve Terminals ◽  
Phagocytic Cells ◽  
Adult Rat ◽  
Intrafusal Fibres ◽  
Nuclear Chain ◽  
Nuclear Bag

Soleus muscle of adult rat is revascularized 5–8 days after sectioning the supplying blood vessels. The temporary ischaemia thus produced results in the rapid concomitant degeneration of extra- and intrafusal muscle fibres along with their nerve terminals and supplying axons. The basal lamina of all muscle fibres usually remains intact throughout the degenerative phase. Necrotic sarcoplasm is removed by phagocytic cells. Satellite cells survive the temporary ischaemia and give rise to presumptive myoblasts which fill the basal-lamina tubes. These myoblasts fuse to form myotubes which, by the 14th day after devascularization, are maturing into muscle fibres in the absence of any innervation. Within the spindle, nuclear-bag fibres degenerate more rapidly than nuclear-chain fibres. Regeneration proceeds more rapidly within the basal-lamina tubes of the original bag fibres than within those of the chain fibres. Reinnervation of regenerating extra- and intrafusal fibres begins 21 days after devascularization and is completed some 7 days later, during which time further equatorial differentiation of some reinnervated intrafusal fibres may occur. Regenerated spindles vary considerably with respect to their innervation and equatorial nucleation. Most contain short, thin, additional muscle fibres as well as those that have regenerated within the basal-lamina tubes of the original fibres.

Structural Properties of the Female Accessory Gland in the Stable Fly, Stomoxys calcitrans

1995 ◽  
Vol 30 (3) ◽  
pp. 362-373
Author(s):  
Benjamin J. Cook ◽  
Nan W. Pryor
Keyword(s):  
Inclusion Bodies ◽  
Circular Muscle ◽  
Accessory Gland ◽  
Stable Fly ◽  
Dense Bodies ◽  
Granular Matrix ◽  
The Common ◽  
Dense Inclusion ◽  
Disk Region ◽  
T System

The accessory reproductive glands of the female stable fly are translucent structures that run parallel to the common oviduct when the ovipositor is extended. The only muscles found associated with the gland were those at either end of the long tube of simple cuboidal epithelial cells. The posterior region of each gland is connected to the anterior vagina by means of a valve of circular muscle. The myofibrils of the valve are separated into sarcomeres of irregular alignment with Z disks that appear as discontinuous rows of dense bodies. Transections through the Z disk region also revealed a perforated character which is common in muscles that have the ability to super contract. The sarcolemma of many cells have tubular invaginations that correspond to the T-system of tubules found in most muscles. Terminal axons with both synaptic vesicles and larger neurosecretory granules were found in close apposition to muscle fibers of the valve. Large vacuoles (with a mean of 26.36 μm and a SD = ± 2.09) were the most prominent structures in the cytoplasm of the glandular epithelium. The fine structure of these vacuoles showed a microvillar border and a central portion that contains clumps of secretory material in a granular matrix. Many vacuoles also contain dense inclusion bodies while other inclusion bodies were observed in apical membranous networks just beneath the cuticular intima. Such ultrastructural features suggest a largely merocrine type secretion for this gland.

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