scholarly journals MORPHOLOGICAL AND BIOCHEMICAL STUDIES OF ISOLATED MITOCHONDRIA FROM FETAL, NEONATAL, AND ADULT LIVER AND FROM NEOPLASTIC TISSUES

1967 ◽  
Vol 34 (2) ◽  
pp. 513-523 ◽  
Author(s):  
Helen A. Mintz ◽  
David H. Yawn ◽  
Brian Safer ◽  
Edward Bresnick ◽  
Annabel G. Liebelt ◽  
...  
Keyword(s):  
Structural Changes ◽  
Respiratory Control ◽  
Electron Microscopic Examination ◽  
Neonatal Rat ◽  
Adult Liver ◽  
Electron Microscopic ◽  
Isolated Mitochondria ◽  
Biochemical Investigation ◽  
Ca Uptake ◽  
Contraction Cycle

A combined morphological and biochemical investigation of mitochondria from developing and rapidly growing tissues ( tumors, fetal, and very early neonatal rat liver) revealed mitochondria which were deficient in respiratory control, showed no valinomycin induced K+ accumulation or spontaneous Ca++ uptake, and were unable to undergo a swelling-contraction cycle. Electron microscopic examination of fetal and neonatal livers and a mammary tumor revealed mitochondria which differed from controls with respect to matrix density and ability to undergo reversible structural changes. The importance of isolation and assay media in interpretation of results is emphasized.

scholarly journals Indomethacin administered early in the postnatal period results in reduced glomerular number in the adult rat

2014 ◽  
Vol 307 (10) ◽  
pp. F1105-F1110 ◽  
Author(s):  
A. L. Kent ◽  
M. E. Koina ◽  
L. Gubhaju ◽  
L. A. Cullen-McEwen ◽  
J. F. Bertram ◽  
...  
Keyword(s):  
Structural Changes ◽  
Ductus Arteriosus ◽  
Electron Microscopic Examination ◽  
Postnatal Period ◽  
Neonatal Rat ◽  
Electron Microscopic ◽  
Adult Rat ◽  
Unbiased Stereology ◽  
Rat Pups ◽  
Glomerular Number

Indomethacin and ibuprofen are administered to close a patent ductus arteriosus (PDA) during active glomerulogenesis. Light and electron microscopic glomerular changes with no change in glomerular number were seen following indomethacin and ibuprofen treatment during glomerulogenesis at 14 days after birth in a neonatal rat model. This present study aimed to determine whether longstanding renal structural changes are present at 30 days and 6 mo (equivalent to human adulthood). Rat pups were administered indomethacin or ibuprofen antenatally on days 18–20 (0.5 mg·kg−1·dose−1 indomethacin; 10 mg·kg−1·dose−1 ibuprofen) or postnatally intraperitoneally from day 1 to 3 or day 1 to 5 (0.2 mg·kg−1·dose−1 indomethacin; 10 mg·kg−1·dose−1 ibuprofen). Control groups received no treatment or normal saline intraperitoneally. Pups were killed at 30 days of age and 6 mo of age. Tissue blocks from right kidneys were prepared for light and electron microscopic examination, while total glomerular number was determined in left kidneys using unbiased stereology. Eight pups were included in each group from 14 maternal rats. At 30 days and 6 mo, there were persistent electron microscopy abnormalities of the glomerular basement membrane in those receiving postnatal indomethacin and ibuprofen. There were no significant light microscopy findings at 30 days or 6 mo. At 6 mo, there were significantly fewer glomeruli in those receiving postnatal indomethacin but not ibuprofen ( P = 0.003). In conclusion, indomethacin administered during glomerulogenesis appears to reduce the number of glomeruli in adulthood. Alternative options for closing a PDA should be considered including ibuprofen as well as emerging therapies such as paracetamol.

Properties of Isolated Mitochondria of Agaricus Bisporus: Their Relationship to Dormancy and the Germination of Spores

1973 ◽  
Vol 31 ◽  
pp. 458-459
Author(s):  
K. S. McCarty ◽  
R. F. Weave ◽  
L. Kemper ◽  
F. S. Vogel
Keyword(s):  
Mitochondrial Dna ◽  
Ethidium Bromide ◽  
Microscopic Examination ◽  
Agaricus Bisporus ◽  
Osmotic Shock ◽  
Electron Microscopic Examination ◽  
Electron Microscopic ◽  
Isolated Mitochondria ◽  
Dna Strands ◽  
Cytoplasmic Ribosomes

During the prodromal stages of sporulation in the Basidiomycete, Agaricus bisporus, mitochondria accumulate in the basidial cells, zygotes, in the gill tissues prior to entry of these mitochondria, together with two haploid nuclei and cytoplasmic ribosomes, into the exospores. The mitochondria contain prominent loci of DNA [Fig. 1]. A modified Kleinschmidt spread technique1 has been used to evaluate the DNA strands from purified whole mitochondria released by osmotic shock, mitochondrial DNA purified on CsCl gradients [density = 1.698 gms/cc], and DNA purified on ethidium bromide CsCl gradients. The DNA appeared as linear strands up to 25 u in length and circular forms 2.2-5.2 u in circumference. In specimens prepared by osmotic shock, many strands of DNA are apparently attached to membrane fragments [Fig. 2]. When mitochondria were ruptured in hypotonic sucrose and then fixed in glutaraldehyde, the ribosomes were released for electron microscopic examination.

THE EFFECTS OF A CARDIAC GLYCOSIDE ON SUBCELLULAR STRUCTURES WITHIN NERVE CELLS AND THEIR PROCESSES IN SYMPATHETIC GANGLIA AND SKELETAL MUSCLE

1962 ◽  
Vol 40 (2) ◽  
pp. 303-315 ◽  
Author(s):  
R. I. Birks
Keyword(s):  
Skeletal Muscle ◽  
Structural Changes ◽  
Motor Nerve ◽  
Electron Microscopic Examination ◽  
Sympathetic Ganglia ◽  
Chloride Ions ◽  
Nerve Cells ◽  
Ion Concentration ◽  
Electron Microscopic ◽  
Pronounced Increase

Nerve cells and their processes in cat sympathetic ganglia and frog skeletal muscle have shown on electron microscopic examination alterations in subcellular morphology as a result of treatment with digoxin. Non-nervous cells were unaffected by the drug. These changes included, in ganglia, swelling of the affected cells, shrinkage of mitochondria with pronounced increase in internal density, swelling of Nissl substance in nerve cell bodies, and loss of structural detail in nerve processes. At the myoneural junction the motor nerve endings were swollen, mitochondria were altered, and the synaptic vesicles were reduced in numbers, those that remained being swollen. These changes were accompanied by invagination of the axon surface by Schwann cell processes.Cell swelling, but not the subcellular changes, was prevented by substitution of sulphate for chloride ions in the extracellular space. When the extracellular sodium ion concentration was reduced to 20 meq/l. the cells were completely protected against digoxin. It is concluded that swelling is caused by net uptake of sodium and chloride as a result of the known inhibitory action of digoxin on sodium extrusion by nerve cells. The possibility that these structural changes in subcellular organelles may be caused by a raised concentration of intracellular sodium ions, such as might occur during activity of excitable cells, is discussed.

Cation Content and Transport Characteristics of the Sickle-Cell Erythrocyte and their Relationship with Structural Changes in the Membrane

1974 ◽  
Vol 46 (6) ◽  
pp. 679-692 ◽  
Author(s):  
J. Kurantsin-Mills ◽  
M. Kudo ◽  
S. Kojo Addae
Keyword(s):  
Sickle Cell ◽  
Sodium Transport ◽  
Structural Changes ◽  
Electron Microscopic Examination ◽  
Active Sodium ◽  
Electron Microscopic ◽  
Potassium Efflux ◽  
Thin Sections ◽  
Sodium Efflux ◽  
Active Sodium Transport

1. The intra-erythrocytic concentrations of sodium and potassium and the water content have been determined for haemoglobin (Hb) SS cells and negroid Hb AA cells. 2. The erythrocyte concentration of sodium was 40% higher and potassium 10% lower in the Hb SS than in the Hb AA cells. The cell water expressed as % weight of cell (corrected for trapped plasma) was identical for both cell types. 3. Normal Caucasian erythrocytes with Hb AA contained 40–50% less sodium but about the same potassium concentration as negroid Hb AA cells. 4. Potassium efflux into buffered iso-osmotic sucrose medium was much faster in Hb SS than in negroid Hb AA cells; ouabain-sensitive active sodium transport was twice as fast in the sickle-cell erythrocytes. Passive sodium efflux of erythrocytes suspended in a physiological medium was similarly faster in Hb SS cells. 5. Under the conditions of the experiments not less than 85% of the Hb SS erythrocytes appeared biconcave. Electron-microscopic examination of ultra-thin sections of Hb SS cells revealed marked discontinuities in the membrane. This suggests definite membrane alterations, which have probably resulted from the sickling-unsickling cycles occurring during the life-span of the cells. 6. It is suggested that the enhanced active sodium transport in the Hb SS erythrocyte is secondary to the augmented passive cation efflux, which in turn results from the leakiness of the erythrocyte membrane produced by the sickling-unsickling process.

scholarly journals The Morphological Assessment of Rats` Liver after the Introduction of the Nucleoside Reverse Transcriptase Inhibitor of Azidothymidine

2019 ◽  
pp. 61-67
Author(s):  
M. N. Kurbat ◽  
R. I. Kravchuk ◽  
O. B. Ostrovskaya
Keyword(s):  
Nucleoside Reverse Transcriptase Inhibitor ◽  
Structural Changes ◽  
Electron Microscopic Examination ◽  
Transcriptase Inhibitor ◽  
Ultrastructural Changes ◽  
Electron Microscopic ◽  
Structural And Functional Properties ◽  
Hepatotoxic Effect ◽  
Reverse Transcriptase Inhibitor ◽  
Morphological Assessment

Objective: to study the microscopic and ultrastructural changes in the liver of rats exposed to AZT. Material and methods. The histological and electron microscopic examination of the liver samples with mitochondrial morphometry has been performed. Results . The 7-day administration of AZT does not cause any significant structural changes in the liver. The exposure to the drug for 21 days leads to the development of moderate inflammatory and degenerative processes in the liver, including changes in the structure of hepatocyte mitochondria. Conclusion. One of the pathogenetic mechanisms of the hepatotoxic effect of AZT is its impact on the structural and functional properties of hepatocyte mitochondria.

THE EFFECTS OF A CARDIAC GLYCOSIDE ON SUBCELLULAR STRUCTURES WITHIN NERVE CELLS AND THEIR PROCESSES IN SYMPATHETIC GANGLIA AND SKELETAL MUSCLE

1962 ◽  
Vol 40 (1) ◽  
pp. 303-315 ◽  
Author(s):  
R. I. Birks
Keyword(s):  
Skeletal Muscle ◽  
Structural Changes ◽  
Motor Nerve ◽  
Electron Microscopic Examination ◽  
Sympathetic Ganglia ◽  
Chloride Ions ◽  
Nerve Cells ◽  
Ion Concentration ◽  
Electron Microscopic ◽  
Pronounced Increase

Nerve cells and their processes in cat sympathetic ganglia and frog skeletal muscle have shown on electron microscopic examination alterations in subcellular morphology as a result of treatment with digoxin. Non-nervous cells were unaffected by the drug. These changes included, in ganglia, swelling of the affected cells, shrinkage of mitochondria with pronounced increase in internal density, swelling of Nissl substance in nerve cell bodies, and loss of structural detail in nerve processes. At the myoneural junction the motor nerve endings were swollen, mitochondria were altered, and the synaptic vesicles were reduced in numbers, those that remained being swollen. These changes were accompanied by invagination of the axon surface by Schwann cell processes.Cell swelling, but not the subcellular changes, was prevented by substitution of sulphate for chloride ions in the extracellular space. When the extracellular sodium ion concentration was reduced to 20 meq/l. the cells were completely protected against digoxin. It is concluded that swelling is caused by net uptake of sodium and chloride as a result of the known inhibitory action of digoxin on sodium extrusion by nerve cells. The possibility that these structural changes in subcellular organelles may be caused by a raised concentration of intracellular sodium ions, such as might occur during activity of excitable cells, is discussed.

Cerebral arterial constriction after experimental subarachnoid hemorrhage is associated with blood components within the arterial wall

1983 ◽  
Vol 58 (1) ◽  
pp. 18-26 ◽  
Author(s):  
Theodore M. Liszczak ◽  
Vassilios G. Varsos ◽  
Peter McL. Black ◽  
J. Philip Kistler ◽  
Nicholas T. Zervas
Keyword(s):  
Subarachnoid Hemorrhage ◽  
Structural Changes ◽  
Arterial Wall ◽  
Autologous Blood ◽  
Electron Microscopic Examination ◽  
Electron Microscopic ◽  
Content Type ◽  
Arterial Lumen ◽  
Angiographic Vasospasm ◽  
Basilar Arteries

✓ Sequential cisternal blood injections in dogs reproduce some of the morphological and physiological features seen in man after subarachnoid hemorrhage-induced vasospasm. This study reports the morphological features observed in cerebral vessels in areas exposed to subarachnoid blood. Subarachnoid hemorrhage was produced in dogs by two cisternal injections of non-heparinized autologous blood 48 hours apart. Dogs were sacrificed 48 hours after the second injection. Angiographic narrowing of the basilar artery was routinely present 48 hours after the second injection, and there was a good correlation between angiographic vasospasm and a narrowed arterial lumen at postmortem examination. All basilar arteries showed structural changes with electron microscopic examination; these included endothelial cell vacuoles, early smooth-muscle cell necrosis, intimal changes, and adventitial erythrocytes, leukocytes, and mast cells. The finding that accompanied vessel constriction most uniformly was packing of the adventitial cerebrospinal fluid spaces with erythrocytes. Angiographically visible spasm was resistant to vasodilators. These data suggest that infiltration of blood elements into the arterial wall is an important concomitant feature of morphological and angiographic vasospasm.

Electron microscopic studies on ultrathin frozen sections of lactating mouse mammary gland

1978 ◽  
Vol 36 (2) ◽  
pp. 46-47
Author(s):  
Jan Zarzycki ◽  
Joseph Szroeder
Keyword(s):  
Mammary Gland ◽  
Protein Denaturation ◽  
Chemical Constituents ◽  
Freeze Substitution ◽  
Electron Microscopic Examination ◽  
Mouse Mammary Gland ◽  
Electron Microscopic ◽  
Preparation Methods ◽  
Microscopic Studies ◽  
Ultrathin Frozen Sections

The mammary gland ultrastructure in various functional states is the object of our investigations. The material prepared for electron microscopic examination by the conventional chemical methods has several limitations, the most important are the protein denaturation processes and the loss of large amounts of chemical constituents from the cells. In relevance to this,one can't be sure about a degree the observed images are adequate to the realy ultrastructure of a living cell. To avoid the disadvantages of the chemical preparation methods,some autors worked out alternative physical methods based on tissue freezing / freeze-drying, freeze-substitution, freeze-eatching techniqs/; actually the technique of cryoultraraicrotomy,i,e.cutting ultrathin sections from deep frozen specimens is assented as a complete alternative method. According to the limitations of the routine plastic embbeding methods we were interested to analize the mammary gland ultrastructure during lactation by the cryoultramicrotomy method.

A Comparative Study of Fractographic Replicas

1974 ◽  
Vol 32 ◽  
pp. 566-567
Author(s):  
Loren Anderson ◽  
Pat Pizzo ◽  
Glen Haydon
Keyword(s):  
Electron Microscopy ◽  
Electron Microscopic Examination ◽  
Direct Examination ◽  
Electron Microscopic ◽  
Reliable Technique ◽  
Service Failures ◽  
Transmission Electron ◽  
Mode Of Failure ◽  
Scanning Electron Microscopic ◽  
Scanning Electron

Transmission electron microscopy of replicas has long been used to study the fracture surfaces of components which fail in service. Recently, the scanning electron microscope (SEM) has gained popularity because it allows direct examination of the fracture surface. However, the somewhat lower resolution of the SEM coupled with a restriction on the sample size has served to limit the use of this instrument in investigating in-service failures. It is the intent of this paper to show that scanning electron microscopic examination of conventional negative replicas can be a convenient and reliable technique for determining mode of failure.

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