Fine structure of the kidneys of osmotically stressed Mytilus, Mercenari, and Anodonta

1986 ◽  
Vol 64 (12) ◽  
pp. 2779-2787 ◽  
Author(s):  
Hamidur R. Khan ◽  
Mary Lou Ashton ◽  
A. S. M. Saleuddin
Keyword(s):  
Basal Membrane ◽  
Ultrastructural Changes ◽  
Freshwater Bivalve ◽  
Septate Junctions ◽  
Intramembrane Particle ◽  
Marine Bivalves ◽  
Fluorescent Stain ◽  
Cytoskeletal Elements ◽  
Lateral Cell ◽  
Membrane Infoldings

Osmotically induced ultrastructural changes in the kidneys of the freshwater bivalve Anodonta and the marine bivalves Mytilus and Mercenaria were studied. Osmotic stresses were given to Anodonta by keeping them in distilled water or in 6% seawater, and to Mytilus and Mercenaria by keeping them in 50% seawater for various periods. In all of these bivalves, the convoluted, single cell layered kidney epithelia displayed wide lateral intercellular spaces as well as extracellular spaces in the basal membrane infoldings during hyposmotic stress. These spaces were greatly reduced when the animals were kept in isosmotic media (i.e., isosmotic to their respective hemolymphs). The kidney cells contained abundant cytoskeletal elements and microfilaments were often observed in bundles in the basal membrane infoldings. Actin was observed in the basal membrane infoldings using the specific fluorescent stain nitrobenzoxadiazole-phallacidin. The cell contacts of the kidney epthelia were studied in platinum replicas of freeze-fractured tissues. The lateral cell membrane and basal membrane infoldings contained many gap junctions. Many rows of dense intramembrane particles of septate junctions were observed in the kidneys of animals from isosmotic media. The septate junctions in the kidneys of aminals from hyposmotic media contained either fewer intramembrane particle rows or many sinuous intramembrane particle rows. The site of prourine formation in mollusks are discussed.

Effect of vinblastine and cytochalasin B on the cytoskeletal domains in 3T3 cells

1981 ◽  
Vol 48 (1) ◽  
pp. 55-73
Author(s):  
J.H. Temmink ◽  
H. Spiele
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Cytochalasin B ◽  
Morphological Changes ◽  
Ultrastructural Changes ◽  
3T3 Cells ◽  
Cytoplasmic Material ◽  
Transmission Electron ◽  
Cytoskeletal Elements ◽  
Scanning Electron

Normal 3T3 cells were exposed to vinblastine and cytochalasin B in an attempt to correlate the morphological changes of the cell surface as seen in the scanning electron microscope with ultrastructural changes of the cytoskeletal elements as seen in critical-point-dried cells in the transmission electron microscope. Special attention was given to the changes in the cytoplasmic domains distinguished in a previous paper. Cytochalasin B primarily affects the ultrastructure of the cytocortical domain by inducing the formation of condensation foci on the cytoplasmic material. Vinblastine not only induces the depolymerization of microtubules and the perinuclear concentration of intermediate filaments, but it also causes the disappearance of stress fibres from the cortical cytoplasm and the widening of the cytocortex at the expense of the endoplasmic domain. These results support the hypothesis that the differentiation in ultrastructural domains is dependent on the spreading of the cells and their adhesion to substrate.

Schistosoma mansoni: an in vivo study of drug-induced autophagy in the gastrodermis

1984 ◽  
Vol 58 (1) ◽  
pp. 59-68 ◽  
Author(s):  
Johanna Clarkson ◽  
D. A. Erasmus
Keyword(s):  
Schistosoma Mansoni ◽  
Hydrolytic Enzyme ◽  
Enzyme Reaction ◽  
Basal Membrane ◽  
Ultrastructural Changes ◽  
Drug Induced ◽  
Cytoplasmic Material ◽  
Intracellular Digestion ◽  
Cell Components

AbstractThe effects of Astiban, Lucanthone, Hycanthone and Niridazole on autophagic activities in the gastrodermis of Schistosoma mansoni were determined in vivo, using different dosage levels and dosage times. With Astiban, high levels of autophagy were observed in the gastrodermis 2 hours after an injection of the drug into the mouse, and this response had declined by 20 hours, marking a recovery by the parasite from the drug. Hycanthone and Lucanthone produced an autophagic response several days after the onset of treatment, and no recovery was observed in the morphology of the gastrodermis after the drug was discontinued. The effects of Niridazole on the gastrodermis were to produce the most dramatic ultrastructural changes after high doses and over several days of treatment. With all the drugs examined, gastrodermal autophagy was characterized by the formation of vacuoles containing cell components, lipid droplets and sometimes hydrolytic enzyme reaction product. The autophagic vacuoles appeared to be formed by the sequestration of cytoplasmic material by the basal membrane infoldings, and the transfer of enzymes into the vacuole from within the limiting membrane. The residues from intracellular digestion appeared to be emptied into the caecal lumen.

scholarly journals Ultrastructural Changes in the Liver of Intravenous Heroin Addicts

2010 ◽  
Vol 10 (1) ◽  
pp. 38-43 ◽  
Author(s):  
Goran Ilić ◽  
Radovan Karadžić ◽  
Lidija Kostić-Banović ◽  
Jovan Stojanović ◽  
Aleksandra Antović
Keyword(s):  
Endoplasmic Reticulum ◽  
Plasma Membrane ◽  
Liver Tissue ◽  
Smooth Endoplasmic Reticulum ◽  
Decisive Role ◽  
Basal Membrane ◽  
Ultrastructural Changes ◽  
Heroin Addicts ◽  
Transmission Electron ◽  
Ultrastructural Findings

The ultrastructural research has a decisive role in gathering the knowledge on the liver’s response to the influence of some drugs. The aim of the study was to perform an ultrastructurai analysis of the liver in chronic intravenous heroin addicts.The study involved the autopsy conducted on 40 bodies of intravenous heroin addicts and 10 control autopsies. The liver tissue was fixed in glutaraldehyde and moulded with epon for investigation purposes of ultrastructural changes. The analysis was performed using the method of transmission electron microscopy.In the group of intravenous heroin addicts, the liver autopsy samples showed degenerative vesicular and fat changes, chronic active and persistent hepatitis, cirrhosis, reduction in the amount of glycogen in hepatocytes, as well as the Kupffer cell’s dominant hypertrophy. Various changes occur in organelles, plasma membrane of hepatocytes and biliary channels as well as in the nucleus.The most important ultrastructural findings include: hyperplasia and hypertrophy of the smooth endoplasmic reticulum, which is histologically proven vesicular degeneration of hepatocyte occurring as a result of the increased synthesis of enzymes of smooth endoplasmic reticulum due to chronic intravenous heroin intake, and the presence of continuous basal membrane followed by transformation of the sinusoids into capillaries (in the cases of chronic active hepatitis and cirrhosis) which leads to a disorder of microcirculation and further progress of cirrhosis.

scholarly journals P0120FEATURES OF ULTRASTRUCTURAL CHANGES IN KIDNEY TISSUE IN THE PATIENTS WHO HAVE PASSED AWAY AS A RESULT OF SEPSIS

2020 ◽  
Vol 35 (Supplement_3) ◽  
Author(s):  
Mehman Agayev ◽  
Shalala Ismayilova ◽  
Arzu Ibishova
Keyword(s):  
Renal Failure ◽  
Structural Changes ◽  
Early Stage ◽  
Kidney Tissue ◽  
Basal Layer ◽  
Basal Membrane ◽  
Renal Tissue ◽  
Ultrastructural Changes ◽  
Severe Renal Failure ◽  
Distal Tubules

Abstract Background and Aims It is believed that septicemia and septicopyemia can lead to functional failure of many organs, including the kidneys. In this regard, it is important to study the morphological features of ultrastructural changes in kidney tissue. Method Structural changes in renal tissue of 30 patients who died as a result of sepsis were investigated by electron-microscopy. The burial was carried out at an early stage (1-6 hours after death). The sections obtained for ultrasonic examination were examined on “James 100 S ” electron microscope after contrasting with uranyl acetate and lead citrate solution. Results An ultrastructural study of the cells of the cortical and medial layers of the kidneys revealed that there are changes in extracellular contacts and cell fragmentation as a result of lysis of the cytoplasmic membrane of cells. The integrity of the basal membrane of epithelial cells of the proximal and distal tubules are preserved. However, the basal layer did not have a homogeneous structure, intersected and transparent in certain areas. Numerous vacuoles, lipid supplements and fragments of lysed intracellular proteins in the cytoplasm have been identified in the cytoplasm of cells. Most of the nucleus was in the collapse phase. The lumen of tubules is narrow and most of the microvilli of the brush border are destructed. It was revealed that in sepsis renal failure and severe destructive changes and the formation of necrosis sites in the structural elements of the nephron as a result of bacterial toxins were mainly observed in areas where bacteria were localized. Conclusion Abnormalities of podocytes, of endothelial cells, disruption of the basal membrane layers as a result of abnormal damage of organelles especially mitochondria, changes of proximal and distal tubules may be caused by severe renal failure due to sepsis.

Topography and Ultrastructure of the tegument of adultSchistosoma mekongi

Parasitology ◽  
1984 ◽  
Vol 89 (3) ◽  
pp. 511-521 ◽  
Author(s):  
P. Sobhon ◽  
E. S. Upatham ◽  
Diane J. McLaren
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Outer Membrane ◽  
Inclusion Bodies ◽  
Unique Feature ◽  
Basal Membrane ◽  
The Body ◽  
Transmission Electron ◽  
Schistosoma Mekongi ◽  
Membrane Infoldings

SUMMARYThe tegument of adultSchistosoma mekongihas been studied by both scanning and transmission electron microscopy. The gross surface topography of the parasite resembles that ofS. japonicum, in that branched ridges, microvilli and sensory papillae predominate; such characteristics distinguish these two species from the non-oriental schistosomes. A unique feature ofS. mekongi, however, is the numerous pleomorphic protruberances which are concentrated particularly on the middle three-fourths of the body surface. Transmission electron microscopy has revealed that these protruberances enclose bundles of microfilaments which appear to insert into the tegumental outer membrane. The microfilaments are suggested to have a supportive or stabilizing function, and may compensate for the absence of more typical crystalline spines. The tegumental outer membrane is typically heptalaminate in section, while the basal membrane infoldings are surrounded by concentrations of mitochondria. Three types of tegumental inclusion bodies have been recognized. Discoid bodies and membraneous bodies are morphologically identical to those described in all other schistosome species, except that the latter inclusions have been seen connected to each other and to the tegumental outer membrane by unique channels lined with trilaminate membrane. The third inclusion takes the form of spherical, lucent vesicles containing membrane fragments; these may represent the remains of spent membraneous bodies.

ULTRASTRUKTURELLE VERÄNDERUNGEN DER ZELLMEMBRAN, BASALMEMBRAN UND KAPILLARE BEI VERSCHIEDENEN FUNKTIONSZUSTÄNDEN DER MENSCHLICHEN SCHILDDRÜSE

1972 ◽  
Vol 69 (3) ◽  
pp. 459-472 ◽  
Author(s):  
Peter Matthaes
Keyword(s):  
Membrane Potential ◽  
Basal Membrane ◽  
Human Thyroid ◽  
List Type ◽  
Cell Border ◽  
Morphological Criteria ◽  
Lateral Cell ◽  
Tsh Stimulation ◽  
State Of Activity ◽  
Metabolic Exchange

ABSTRACT Apical and basal membranes of activated cells show definite increase in membrane potential. Microvilli are frequently encountered, pseudopodia representing macropinocytosis infrequently. The lateral cell border shows definite morphological criteria of intercellular metabolic exchange. Small ducts lined by microvilli are described and discussed as to their relation to lymphatics. The formation and desintegration of the basal membrane is determined by hormonal (TSH) stimulation and the state of activity of the cell. Intraepithelial capillaries occurring in the human thyroid are described. Polar differentiation analogous to other organs can be demonstrated here as well.

Ultrastructure and microanalyses of the protoscolex hooks ofEchinococcus granulosus

Parasitology ◽  
1991 ◽  
Vol 103 (2) ◽  
pp. 267-274 ◽  
Author(s):  
S. A. Smith ◽  
K. S. Richards
Keyword(s):  
Echinococcus Granulosus ◽  
Appearance Energy ◽  
Basal Membrane ◽  
Proximal Region ◽  
X Ray Diffraction ◽  
Outer Cortex ◽  
Additional Material ◽  
X Ray ◽  
Diffraction Patterns ◽  
Membrane Infoldings

The rostellar distal cytoplasm ofEchinococcus granulosusprotoscoleces is characterized by extensive basal membrane infoldings, prominent hemidesmosomes and is subtended by a lamina reticularis with microfibrils of approximately 10 nm diameter that occasionally show a 55 nm banding periodicity. The rostellar hooks, in 2 rows, each have a blade, guard and handle region and possess a central amorphous pulp, a middle microfibrillar medulla with microfibrils of approximately 4 nm diameter, and a complex outer cortex in all but the proximal region of the guard and the base of the handle. In these regions additional material, of similar electron density to the medulla, but lacking the fibrillar substructure, occurs and gives the areas a lobed appearance. Energy-dispersive X-ray microanalysis of whole hooks demonstrated the presence of sulphur and trace quantities of phosphorus. X-ray near-edge absorption spectra resembled those of cystine, feather and hair and showed the sulphur to be predominantly in the form of disulphide linkages. X-ray diffraction patterns of whole hook preparations revealed 2 diffuse rings with equatorial spacings of 7·99 Å and 15·22 Å, thus differing from vertebrate keratins.

Fine Structural Changes in the Microvasculature of the Mouse Pinna: Aging and Radiation Injury

1974 ◽  
Vol 32 ◽  
pp. 54-55
Author(s):  
S. Phyllis Steamer ◽  
Rosemarie L. Devine
Keyword(s):  
Structural Changes ◽  
Radiation Treatment ◽  
Arterial Stenosis ◽  
Ultrastructural Changes ◽  
Vascular Effects ◽  
Microvascular Changes ◽  
Surrounding Connective Tissue ◽  
Fission Neutrons ◽  
Total Body

The importance of radiation damage to the skin and its vasculature was recognized by the early radiologists. In more recent studies, vascular effects were shown to involve the endothelium as well as the surrounding connective tissue. Microvascular changes in the mouse pinna were studied in vivo and recorded photographically over a period of 12-18 months. Radiation treatment at 110 days of age was total body exposure to either 240 rad fission neutrons or 855 rad 60Co gamma rays. After in vivo observations in control and irradiated mice, animals were sacrificed for examination of changes in vascular fine structure. Vessels were selected from regions of specific interest that had been identified on photomicrographs. Prominent ultrastructural changes can be attributed to aging as well as to radiation treatment. Of principal concern were determinations of ultrastructural changes associated with venous dilatations, segmental arterial stenosis and tortuosities of both veins and arteries, effects that had been identified on the basis of light microscopic observations. Tortuosities and irregularly dilated vein segments were related to both aging and radiation changes but arterial stenosis was observed only in irradiated animals.

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