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At least 19 recordsLinked to original sources
PubMed1978

Fibrillar bodies in leukemic cells revealed by polarization microscopy.

An optical polarizing microscope with a good coefficient of extinction permits the visualization of the cytoplasmic fibrillar body in living preparations and smears of leukemic cells (human leukemias and the L 5222 experimental leukemia). These inclusions are not visible by phase contrast microscopy nor in fixed and stained smears. The detection in living cells of fibrillar bodies makes it possible to study directly the conditions for their formation and their reaction to the effect of certain drugs.

Actin Cytoskeleton↗
PubMed1977

[On applicabilities of polarization microscopy in diagnostic histopathology (author's transl)].

Apart from its importance in ultrastructure research polarization microscopy turns out to be a valuable additional method in the daily hitological diagnostics of pathologist. By means of some examples the applicabilities of the polarization microscopy in this field are demonstrated. After some physical bases and practical hints for the use of polarization microscopes some staining reactions leading to an optical anisotropic effect are reported. Morever, it is reffered to the demonstration and characterization of crystals in biological fluids and tisdues. In our opinion, simple polarization optics should belong to the optical equipment of each pathologist.

Aorta↗
PubMed1991

Crystalluria determined by polarization microscopy. Technique and results in healthy control subjects and patients with idiopathic recurrent calcium urolithiasis classified in accordance with calciuria.

A retrospective study was done on the nature and degree of crystalluria in spontaneously voided fasting and postprandial urine of patients with recurrent idiopathic calcium urolithiasis (RCU) divided into normocalciuria (20 males, 20 females) and hypercalciuria patients (20 males, 20 females), and controls (20 males, 20 females). The crystals were obtained using a filter technique and identified by microscopy. In addition, individual data, clinical chemistry variables and indices reflecting the risk of calcium phosphate and calcium oxalate crystallization were evaluated. In contrast to findings of other investigators of crystalluria we observed only a few crystals on the filters. The most frequently occurring phases were (in this order) a urate-containing phase (tentatively termed uric), an amorphous calcium phosphate phase (tentatively termed isotropic) and a phase of spheroid-like particles, not yet definitely characterized (tentatively termed spheroid). Calcium oxalate crystals were found only exceptionally. There was no relationship between the degree of calciuria (normo- versus hypercalciuric RCU) and crystalluria. Among RCU, males generally had a predominance of the isotropic, females of the spheroid phase, as compared with controls. Also, RCU females were generally obese, and their spheroid score and lean body mass correlated negatively and significantly. The calcium phosphate and calcium oxalate risk indices were always low in normal individuals, higher in RCU. Patients of both sexes with urinary stones had normal parathyroid gland function, but higher total calcium in fasting serum and higher urinary pH as compared with controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

[Spheno-occipital synchondrosis--a fluorescence and polarization microscopy study in Cercopithecus aethiops monkeys].

On 17 Cercopithecus aethiops monkeys we investigated with the method of the polychromic sequential dye marking system the histomorphology as well as the dynamics of growth and calcification of the spheno-occipital synchondrosis. The age of the animals ranged from change to teeth to late adolescence. The animals had been divided into four different groups: I: late change of teeth; II: young adult; III: fully grown; IV: late adolescence. In the first group the spheno-occipital synchondrosis showed no ossification in the gap which is filled with cartilage. It showed the characteristic structure with a central zone of equally distributed chondrocytes. Adjacent to this we found a zone of proliferation cell hypotrophy and cell degeneration. With increasing age there is decrease of the density of cells (groups II to IV) and after change to teeth the synchondrosis starts to ossify (group II). Due to the ossification the synchondrosis subdivides into different cartilage regions. We found that the closing of the synchondrosis started in the cranial region and progressed toward the caudal region. During this procedure the synchondrosis never ossified completely. Several cartilage regions persisted uncalcified until late adolescence. Interstitial growth of the synchondrosis was found until the end of the change of the teeth (group I). This growth which was always found in a sagittal direction ceased after bony connections had been formed between both poles of the synchondrosis. The sphenoidal and occipital pole of the synchondrosis showed equal growth potential.

Aging↗
PubMed1976

Compensator transducer increases ease, accuracy, and rapidity of measuring changes in specimen birefringence with polarization microscopy.

An instrument has been designed to improve substantially the efficiency and convenience of measuring specimen birefringence retardation (BR) with a conventional Brace-Köhler compensator. The design is based on the precise transduction of the angular position of the compensator's Vernier dial to an easily visible red-illuminated display on a digital voltmeter. The instrument display is accurate to within 0.1 degrees over a range of +/-25 degrees in the compensator vernier dial position which is similar to the precision obtainable with an ordinary vernier and the Brace-Köhler method of measuring BR of biological specimens. For convenience in data reduction the display can also be read directly in nanometre units, with a similar precision for specimen BR in the range of 5 nm or less which is typical of birefringent fine structures in living cells.

Birefringence↗
PubMed1991

[Dye analytical investigations on the polarization microscopy detection of collagen with Sominrot 4B (Part II)].

We use the disazo dyestuff Solaminrot 4B for the visualization of collagen fibres in the morphological substratum investigated. The dye selectively enhance the birefringency of the fibres. Therefore, the parts of this paper are dealing with the dye properties of 2 charges of Solaminrot 4B produced by Chemie AG Bitterfeld--Wolfen. The 1st charge contain supplementary substances; the 2nd charge is without ones. We used various physicochemical methods, e.g. chromatography, spectroscopy, and electrophoresis. Moreover, we analyzed the solubility of dye in inorganic and organic solventia, the phase dispersion in benzen and octanol, the influence of the dye probes on the pH values of the dye solutions, and so on. The results indicate that the physicochemical properties of both charges investigated by us are partially different. This is important for the application of Sirius Red dyestuffs to the histological staining procedures.

Azo Compounds↗
PubMed1991

Lipid order in hepatocyte plasma membrane blebs during ATP depletion measured by digitized video fluorescence polarization microscopy.

Low-light digitized video fluorescence polarization microscopy was used to measure lipid order parameters in plasma membrane blebs of single, cultured rat hepatocytes during ATP depletion with the metabolic inhibitors cyanide and iodoacetic acid. Hepatocytes were labeled on the microscope stage with the plasma membrane probe trimethylammoniumdiphenylhexatriene at successive stages of cell injury. A pair of fluorescence polarization ratio images was obtained from a series of four fluorescence images recorded with a polarizer in the emission path oriented first parallel and then perpendicular to each of two orthogonal excitation light polarization directions. From the polarization ratio images, the lipid order parameter S was determined in individual plasma membrane blebs. Results indicate that the plasma membrane becomes uniformly rigid within a few minutes of the addition of metabolic inhibitors when small surface blebs have formed and ATP levels have fallen by greater than 95%. The measured order parameter of S approximately 0.95 in plasma membrane blebs, compared with S approximately 0.75 in normoxic cell plasma membranes, remained unchanged throughout the course of bleb development and ultimate cell death. These findings demonstrate that significant alteration in hepatocyte plasma membrane structure occurs early in hypoxic cell injury.

Adenosine Triphosphate↗
PubMed1978

Differential staining of collagens type I, II and III by Sirius Red and polarization microscopy.

Organs of fish, amphibian, reptile, bird and mammals when stained by Sirius Red and studied with polarization microscopy present different colors in regions where collagens I, II and III have been described. Collagen type I presented a yellow, orange or red color while collagen type III appeared green. Collagen type II, present in cartilage and chondrosarcoma showed a variable color according to the tissue and the species. Its color and morphology however always permitted its clear distinction from collagens type I and type III.

Animals↗
PubMedDate not supplied

Submicroscopic structure of glycosaminoglycans in osteocyte capsule of human embryonic bone as revealed by polarization microscopy.

Using qualitative and quantitative polarization microscopical techniques, an axiparallel orientation of chondroitin sulfate molecules and collagen fibrils could be detected in the osteocyte capsule of human embryonic and fetal bones. It is suggested that this spatially oriented microstructure plays a role in ana- and catabolic transport processes of the bone tissue.

Bone and Bones↗
PubMedDate not supplied

The collagenous architecture of articular cartilage. Correlation of scanning electron microscopy and polarized light microscopy observations.

The localization and directional orientation of collagen fibers in articular cartilage is demonstrated by scanning electron microscopy and polarized light microscopy. Vertical sections of articular cartilage show different directional orientations of collagen fibers through all zones of cartilage depending upon whether the sections are parallel or perpendicular to the cleft pattern produced when the surface of articular cartilage is pierced with a round pointed awl. Sections parallel to the cleft axis show a significant population of oblique collagen fibers which are not seen in sections perpendicular to the clefts. These oblique fiber groups show a progression from nearly radial to nearly tangential orientation from deep to more superficial zones, with the most abrupt directional change seen through the transitional zone. Within the transitional zone there is a narrow band having no vertical or horizontal collagen fibers and in which collagen fibers intersect predominantly at angles ranging between 45 and 135 degrees. The number of chondrocyte lacunae per unit area is greater in sections parallel to the cleft axis compared to perpendicular sections by a factor of approximately 1.6:1. There is therefore a greater relative number of chondrocytes in the plane of section having the greatest abundance of oblique collagen fibers, suggesting a cellular basis for the collagenous architecture observed. The results are consistent with published biophysical data relating tensile and swelling properties of all zones of articular cartilage to the cleft axis.

Animals↗