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PubMed1980

Comparative light and electron microscopic study of the human, dog and rat prostate. An approach to an experimental model for human benign prostatic hyperplasia (light and electron microscopic analysis)--a review.

Stereology was shown in several studies to be a relevant method to study the quantitative amount of tissue and cell compartments of normal and pathological altered prostatic tissue. A morphological comparison of the rat (ventral lobe), dog and human prostate was performed by quantitative morphology. In comparing the light microscopic analysis of the rat ventral prostatic lobe with that of the dog prostate, the volumetric amount of the glandular cells in the dog prostate is two times greater than in the rat (ventral prostatic lobe). In the normal human prostate the volumetric amount of the glandular part was calculated to be 55% of the outer part, respectively 45% in the inner part of the prostate. Regarding the stromal tissue, there is no difference between the dog and the normal human prostate, but a striking difference compared to the rat ventral prostatic lobe, where stromal development seems to be sparse (25%). The quantitative measurements of spontaneous dog and human prostate hyperplasia show that the dog hyperplasia is primarily a glandular disease whereas human benign prostatic hyperplasia reflects more stromal activation. As shown by the electron microscopic measurements in the normal human and dog prostate, there is a similar great volumetric amount of secretory granules. In comparing the data of the rough endoplasmic reticulum, in the rat there is a higher amount than in the normal human and dog prostate. Conversely, the amount of secretory granules is higher in the dog and human prostate than in the rat (ventral prostatic lobe).

Animals↗
PubMed2006

Optical band splitting and electronic perturbations of the heme chromophore in cytochrome C at room temperature probed by visible electronic circular dichroism spectroscopy.

We have measured the electronic circular dichroism (ECD) of the ferri- and ferro-states of several natural cytochrome c derivatives (horse heart, chicken, bovine, and yeast) and the Y67F mutant of yeast in the region between 300 and 750 nm. Thus, we recorded the ECD of the B- and Q-band region as well as the charge-transfer band at approximately 695 nm. The B-band region of the ferri-state displays a nearly symmetric couplet at the B0-position that overlaps with a couplet 790 cm-1 higher in energy, which we assigned to a vibronic side-band transition. For the ferro-state, the couplet is greatly reduced, but still detectable. The B-band region is dominated by a positive Cotton effect at energies lower than B0 that is attributed to a magnetically allowed iron-->heme charge-transfer transition as earlier observed for nitrosyl myoglobin and hemoglobin. The Q-band region of the ferri-state is poorly resolved, but displays a pronounced positive signal at higher wavenumbers. This must result from a magnetically allowed transition, possibly from the methionine ligand to the dxy-hole of Fe3+. For the ferro-state, the spectra resolve the vibronic structure of the Qv-band. A more detailed spectral analysis reveals that the positively biased spectrum can be understood as a superposition of asymmetric couplets of split Q0 and Qv-states. Substantial qualitative and quantitative differences between the respective B-state and Q-state ECD spectra of yeast and horse heart cytochrome c can clearly be attributed to the reduced band splitting in the former, which results from a less heterogeneous internal electric field. Finally, we investigated the charge-transfer band at 695 nm in the ferri-state spectrum and found that it is composed of at least three bands, which are assignable to different taxonomic substates. The respective subbands differ somewhat with respect to their Kuhn anisotropy ratio and their intensity ratios are different for horse and yeast cytochrome c. Our data therefore suggests different substate populations for these proteins, which is most likely assignable to a structural heterogeneity of the distal Fe-M80 coordination of the heme chromophore.

Circular Dichroism↗
PubMed1977

Modified tannin-osmium conductive staining method for non-coated scanning electron microscope specimens. Its application to microdissection scanning electron microscopy of the spleen.

Supplement of guanidine hydrochloride to the original tannic acid solution of MURAKAMI (1973) eliminated, without debilitating the conductivity effect, the vexatious treatment with different amino-acids and sucrose in the previous method (MURAKAMI, 1974). The procedures and advantages of this simplified modification are described using human spleen samples; attempt was made to elucidate the structure of arterial terminals by dissecting the specimens under the scanning electron microscope.

Dissection↗
PubMed1979

Studies of metallobleomycins by electronic spectroscopy, electron spin resonance spectroscopy, and potentiometric titration.

The 1:1 bleomycin-A2-Cu(II) complex shows an absorption maximum at 595 nm (epsilon 120), circular dichroism extrema at 555 nm (delta epsilon + 1.21) and 665 nm (-0.61), and electron spin resonance (ESR) signal with g = 2.211, g = 2.055, and A = 178 x 10(-4) cm-1. The formation constant (log K = 12.630) and deprotonation constant (PKc = 3.585) of the 1:1 bleomycin-Cu(II) complex were determined by computer analysis of potentiometric data. The results of potentiometric titration also indicate that the stability of bleomycin-metal complexes is in the order Fe(II) less than Co(II) less than Ni(II) less than Cu(II) greater than Zn(II) and that these divalent metal complexes have a similar coordination environment. The bleomycin-Cu(II) complex has substantially a square-pyramidal configuration in which the secondary amine nitrogen, pyrimidine(N-1) ring nitrogen, deprotonated peptide nitrogen of histidine residue, and histidine imidazole(N-1) nitrogen coordinate to Cu(II) as planar ligand donors, and the alpha-amino nitrogen as axial donor. The specific Cu(II)-binding site of bleomycin has been compared with that of human serum albumin.

Binding Sites↗
PubMed1975

Comparative electron-microscopic features of normal, hyperplastic, and adenomatous human colonic epithelium. II. Variations in surface architecture found by scanning electron microscopy.

We have used the high resolution and the great depth of focus possible with the scanning electron microscope to define the surface features of normal human colon and human colonic polyps. This technique demonstrates that the surface of the normal colon has a territorialization which encompasses multiple crypts. The surface of the normal colon is covered with both absorptive cells and goblet cells. Hyperplastic polyps are covered with overdeveloped absorptive cells and the normal teritorialization is present but is distorted. Adenomatous polyps are covered with immature cells and, except for the villous adenomas, goblet cells are strikingly absent from the surface. The territorial patterns are totally obliterated in the adenomas.

Adenoma↗
PubMed2001

The application of electron microscopic morphometry as helpful method in the diagnosis of focal segmental glomerulosclerosis (FSGS) early phase. I. Morphometric electron microscopic studies of renal glomeruli in cases of focal segmental glomerulosclerosis (FSGS), minimal change disease (MCD) and mesangioproliferative glomerulonephritis (GNMES) in children.

Electron microscopy morphometric studies were carried out on material obtained from children with minimal change disease (MCD), mesangioproliferative glomerulonephritis (GNMES) and focal segmental glomerulosclerosis (FSGS). The results indicated that an increase in the volume of the matrix in mesangioproliferative glomerulonephritis was due to an increase in the number of cells. The amount of produced matrix in mesangioproliferative glomerulonephritis was proportional to the number of cells in mesangium (so there is no overproduction of matrix). The ratios of mesangial matrix volume to cell volume and matrix volume to the volume of the entire mesangial region in MCD and GNMES were similar and differed significantly from the ratios found in FSGS. The present findings indicate that morphometric studies may be useful in the early diagnosis of glomerular sclerosis. This is particularly significant in cases where light microscopic examination fails to reveal changes indicative of glomerular sclerosis.

Child, Preschool↗
PubMed1976

Mode of action of a surgical electronic lithoclast--high speed pressure, cinematographic and schlieren recordings following an ultrashort underwater electronic discharge.

In order to investigate the mode of action of the electrical discharges from a surgical electronic lithoclast in shattering bladder stones high speed pressure-time recordings were made. The results indicated effects similar to those following an underwater detonation of high explosive. Subsequent high speed photographic analysis confirmed this. Calculations based on the results suggested that the shock waves and pressure pulses generated were of a potentially hazardous magnitude and that gas-containing bowel close to the bladder might be at particular risk as well as solid tissue as the bladder wall. Photographic data also suggested that danger might be incurred by the use of similar devices in a small enclosed space such as the ureter or renal pelvis.

Calculi↗
PubMed1975

[Electron microscopic and electron histochemical study of mitochondrial inclusions in insect intestine epithelial cells].

The electron microscope investigation of the midgut epithelial cells of Chaoborus obscuripes revealed special membrane formations in mitochondria. The mitochondrial inclusions (MI) look like small membranous whorls about 0.2--0.3 microns in diameter. In a certain period of functional activity, MI start leaving the mitochondria and appear in cytoplasm. Later, large multimembrane structures (MS) composed of parallel membranes in concentric or whorl--like arrangement are observed in the cytoplasm. At first MS are situated in the vicinity of mitochondria, then they gather near the base of the villus. The relationship between appearance of MI and MS in the cytoplasm and the digestion process was revealed. Treatment of ultrathin sections with H202 or H5J06 showed MI and MS to be composed mainly of lipids. This suggests that MI and MS,probably, take part in the lipids metabolism of the midgut epithelial cells of insect.

Animals↗
PubMedDate not supplied

[Electron paramagnetic resonance study of electron transport in photosynthetic systems. VIII. The interplay between two photosystems and kinetics of P700 redox transients under various conditions of flash excitation].

The kinetics P700 redox transients in bean chloroplasts induced by short (t 1/2 = 7 microsecond) flashes of white light has been studied. The flashes were fired in the dark or simultaneously with the continuous background far red light (707 nm). After oxidation of electron transport chain by 707 nm light only 50% of P700+ centres were reduced by photosystem 2 in response to the first flash of saturating intensity. The total reduction of P700+ centres was observed only after two or more saturating flashes. The similar data were obtained for various native photosynthetic systems (bean leaves and leaves of other higher plants). It has been shown that the quantitative difference in P700 behaviour after the first and following flashes may be interpreted in terms of a mechanism of the plastoquinol oxidation by photosystem 1. Twofold oxidation of one molecule of plastoquinol was assumed as its successive oxidation to plastosemiquinone and plastoquinone by different acceptors localized nea the same P700 centre (cytochrome f and plastocyanine). It has been shown that one molecule of plastoquinol was arised due to the interaction of two plastosemiquinones reduced by different P680 centre.

Chloroplasts↗
PubMedDate not supplied

[Electron microscopic and electron radioautographic study of cells in glandular hyperplasia and cancer of the endometrium].

Peculiarities of the ultrastructure and RNA synthesis in the epithelial endometrial cells of nine patients with hyperplasia and the uterine cavity cancer have been studied by the electron-radioautographic method. Quantitative differences are revealed in the ultrastructures of the cells. Amplification of the nucleoli labelling and asynchronism of the RNA synthesis in the nucleoli with glandular hyperplasia and endometrial cancer are observed.

Adenocarcinoma↗
PubMed1989

[Electron microscopic detection rate of enteral viruses in diarrhea of dogs, cats, calves, swine and foals in the year 1988--electron microscopic study results].

During 1988 fecal and gut samples of 641 dogs, 198 cats, 576 calves, 108 piglets and 64 foals with diarrhoea were investigated for virus infections by electron microscopy. In samples of dogs and cats parvovirus was detected at a proportion of 21.9% and 16.7%, respectively; rotavirus alone or together with coronavirus was found only in 0.3-1.5% of the specimens. In samples of calves rotavirus, as well as coronavirus dominated with a detection rate amounting to 17.4% and 26.6% respectively (including 4.5% of mixed infections); parvovirus was present in a ratio of 0.5%. Specimens of piglets mainly contained coronavirus (25.0%), and in lower percentages rotavirus (2.8%), rota- and coronaviruses (0.9%) and parvovirus (0.9%). In feces of foals rotavirus was detected in 6.3% and particles resembling picornavirus in 4.7% of cases. Not identifiable virus particles resembling corona-or picornaviruses were rarely found (between 0.6-2.5) also in specimens of the other animal species.

Animals↗
PubMed1989

The electronic spectrum of adenine by electron impact methods.

The electron energy loss spectrum of adenine has been recorded over an excitation energy range of approximately 3-22 eV for scattering angles of 3 degrees and 6 degrees. In addition to reporting accurate vapor phase peak positions, the present work supports the long-held contention that the group of peaks in the 6- to 10-eV range belong to transitions that originate from valence pi orbitals. In the vapor phase spectrum, a Rydberg transition corresponding to an n----3s excitation is readily observed with a term value of 3.45 eV relative to the first long-pair ionization potential.

Adenine↗
PubMed1987

[Initial stages of the myocardial differentiation of the lymph hearts of frog tadpoles. A study by the methods of electron microscopy and electron microscopic autoradiography].

Using electron microscope autoradiography, a study was made of the ultrastructure of early stages of muscle differentiation and 3H-thymidine (3H-T) labelled cells in the wall of the developing lymph heart of larvae of Rana temporaria L. The mononucleated postmitotic myoblasts with small bundles of thin and thick myofilaments deprived of Z-bodies were found in the lymph heart wall. No thin or intermediate-sized subsarcolemmal filaments were detected in the cytoplasm of these myoblasts. Myosatellites occurred under the basal lamina of muscle cells at stages 41-42. The primitive muscle-nerve junction was found at stages 44-45. Four hours after a single 3H-T administration only mononuclear cells without myofilaments were labelled. If the fixation was made 72 hours after a single 3H-T administration, the label was found, in addition, on the muscle cell nuclei. These data evidence that at the early stages of muscle differentiation in the developing lymph heart wall DNA synthesis and muscle specific protein synthesis are incompatible.

Animals↗
PubMed1985

[Mucous membrane changes in the anterior ethmoid bone in chronic sinusitis and mycoses of the paranasal sinuses. An endoscopy, light and electron microscopy study. 2. Electron microscopy findings].

In the second part of this paper the findings of electron microscopical studies on ultrastructural changes of the cilia of the ethmoidal mucous membrane in patients with mycotic chronic sinusitis are presented. Many pathological variations of the normal 9 + 2 pattern can be demonstrated, along with compound cilia and central axis deviation beyond 25 degrees. This together with the endoscopical and lightmicroscopical findings results in conditions which are different from those in acute sinusitis. It may as well explain, why hardly a conservative therapy--aiming mostly for vasoconstriction and decrease of mucosal edema--is successful in chronic sinusitis. Endoscopical surgery of the diseased anterior ethmoid in most of the cases brings along cure of the dependent frontal and maxillary sinuses as well.

Chronic Disease↗
PubMed1985

[Electron microscopic study on the structure and the function of the granulosa cell in the human ovary--in vitro electron microscopic autoradiography on the localization of 17 beta-estradiol receptor complex, DNA synthesis and protein synthesis].

In order to investigate the effect of E2 on the DNA synthesis, the localization of E2-receptor complex at different temperature, and protein synthesis in the granulosa cell of the human ovary, in vitro studies were made using the electron microscopic autoradiography of 10 muCi/ml of 3H-thymidine, 10(-8)M 3H-E2 and 100 muCi/ml of 3H-leucine. In particular, a dry-mounting autoradiographic technique was applied to detect the localization of E2-receptor complex because E2 is a soluble compound. Control incubation was done in the medium containing 10(-8)M 3H-E2 and 500-fold of unlabeled E2. In addition, as to the morphological barriers among granulosa cells, we observed the ovary treated with the 1% fixative containing 1000ppm. of ruthenium red. The labeling index was 27.6 +/- 3.9% in the medium containing E2, while it was 13.1 +/- 2.2% in the control medium (p less than 0.001). The percentage distribution of silver grains in the nucleus indicating the localization of E2-receptor was 77.4 +/- 8.6% at 37 degrees C and 25.4 +/- 9.3% at 4 degrees C respectively (p less than 0.001). The silver grains on the protein synthesis were increased in number with the passage of time and localizaed mainly on the rough endoplasmic reticulum, mitochondria and nucleus. Ruthenium red entered among the granulosa cells. From the data presented here, it is suggested that there are no morphological barriers among granulosa cells showing active protein synthesis, the nuclear transport of E2-receptor complex is dependent upon its temperature, and E2 stimulates DNA synthesis.

Adult↗
PubMed1980

[Electronic calculation trainers for physically handicapped pupils--an example of how to use electronics in the field of individualized instruction at schools for the physically handicapped (author's transl)].

The article demonstrates, on the basis of arithmetic lessons with physically handicapped pupils, that individualised teaching methods can be considerably more effective with the aid of technology. The demand for extreme individualized instruction justified not only by psychological but also physical reasons, is attempted to be met in an important partial area, i.e., the acquisition of arithmetical skills by means of practice. Within the framework of a research project carried out on behalf of the Federal Minister of Labour, a device has been developed which takes into consideration the medical, special educational and technical viewpoints and helps to meet the practical requirements whilst taking into account the multidisciplinary problem complex. the device is an electronic trainer for mental arithmetic exercises which can be constructionally adapted to the pupil's physical deviation. It is programmed by the teacher in accordance with the different performance levels and is then a direct partner irrespective of the pupil's degree of disability.

Child↗
PubMedDate not supplied

[Use of the LUE-25 linear electron accelerator for studying the radiobiological effects of high doses of fast electrons].

In order to study the early biological effects of whole-body and partial exposure of biological objects to high doses of fast electrons a simple and reliable method has been developed for the purposes of the control and correction of the dose-rates. The measurements were made of spatial distribution, in air and water, of the doses used for irradiation of the laboratory animals and cell suspensions with the indicated nonuniformity coefficients.

Dose-Response Relationship, Radiation↗
PubMed1982

[Histogenesis of muscle tissue in the developing lymph hearts of Rana temporaria larvae and younglings. A study by electron microscopic and electron microscopic autoradiographic methods].

Using 3HT electron microscope autoradiography, the ultrastructure of muscle fibers and the capacity of 3HT-incorporation into the nuclei of these fibers and the adjacent cells were studied in the developing lymph hearts of larvae and yearlings of R. temporaria. The presence of myofilaments arranged in sarcomeres of prominent disks Z, I, A, H and M line, and of the well developed sarcoplasmic reticulum may serve a good evidence of a high level of myofibrillar differentiation both in larvae and in yearlings. Myosatellite cells were found in the close contact with muscle fibers at all the investigated stages of the lymph heart development. 4 hours after 3HT administration to larvae, only mononuclear cells deprived of myofibers were seen labeled. The labeled myonuclei were observed in the experiments with double 3HT injections to larvae and with the fixation following 24 hours after the last 3HT administration. These data evidence that, according to the ratio of differentiation and reproduction, the histogenesis of the lymph heart muscle tissues of larvae and yearlings of R. temporaria corresponds to the myogenesis of cross striated skeletal muscles of vertebrates.

Animals↗