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At least 19 recordsLinked to original sources
PubMed1978

Observations of globular membranes and apparent elementary particles in rat mitochondria, in situ.

Ultrastructural details of rat skeletal muscle, fixed in a PIPES-buffered glutaraldehyde solution, included the globular configuration of the outer and inner mitochondrial membranes as well as small transparent particles (80--100A diameter) distributed throughout the matrix of these organelles. The size of these particles and their intimate relationship with the innermost surface of the cristae suggests that they may represent an in situ visualization of the elementary particles once reported in intact cells and frequently observed in negatively stained mitochondrial preparations. The membrane configurations and particles were not discernable in these tissues when a phosphate buffer system was used in the fixation regimen.

Animals↗
PubMed1975

Elementary particles in isolated rat liver and spleen nuclear membranes.

Elementary spherical particles similar to those described in the mitochondria are found in isolated rat liver and spleen nuclear membranes. The particles are characterized by electron microscopy of sections and preparations negatively stained with phosphotungstic acid or with the ATPase histochemical reaction product. The particles exhibit adenosine triphosphatase activity and have a mushroom-like shape with a sphere about 85-90 angstrom in diameter attached to inner face of the inner nuclear membrane by a stalk about 50 angstrom in length and 35 angstrom in diameter. It is supposed that these particles, just as analogous particles localized at the inner mitochondrial membrane, are involved in the coupling of oxidation and phosphorylation in the nuclear envelope.

Adenosine Triphosphatases↗
PubMed1975

The formation of a complex between the membrane structures of the mitochondria and DNA of nonmitochondrial origin.

The ability of decomposed rat liver mitochondria, stripped of their outer membrane (fracton C) to bind 14C-DNA of phage T4 was demonstrated. The bound phage DNA is 10-15% resistant to treatment of fraction C with DNAase I. Treatment of fraction C with sarcosyl (final concentration 0.1%) and centrifugation in a linear sucrose gradient (20-50%) permits the detection of a label in the Mt-DNA-membrane complex, isolated at 35% sucrose. Further fractionation of the membrane complex on sepharose 4 B promotes the detection of the label in "elementary particles of transcription" [1], structural units of the inner membrane, containing specific centers for binding to DNA. The centers of binding of the elementary particles of transcription possess greatest affinity for Mt-DNA; however, they are also capable of binding DNA of various origin (both the DNA of eucaryotes and that of procaryotes). The significance of fixation of DNA of nonmitochondrial origin by the membrane structures of the mitochondria is discussed.

Animals↗
PubMedDate not supplied

[Participation of species specific and group specific ornithosis antigens in immune reactions].

The immunogenic properties of the species-specific antigen localized in the elementary particle membrane and group-specific or inner antigen of the causative agent of ornithosis were studied. The species specific antigen was shown to induce the antibody neutralizing the infectious properties of the agent as well as those agglutinating elementary bodies, inhibiting hemagglutination, and complement-fixing antibody detectable in the direct and indirect complement-fixation tests. The results indicate that the antigens most clearly defining the species-specific properties of the causative agent of ornithosis are localized in the elementary particle membrane. These antigens may be used for differential diagnosis studies employing not only CFT but also other antibody tests.

Agglutination Tests↗
PubMed1975

On the origin of molecular "handedness" in living systems.

Elementary particle effects (beta-decay) provide at best only a weakly handed radiation in the biologically effective energy ranges. Global magnetic effects coupled to sunlight are randomized by paleomagnetic reversals. Hence a persistent terrestrial handed bias at possible local biopoetic sites offers a more promising explanation for the origin of the "handedness" of the molecules found among living systems on earth. Magnetite in lava flows maintains a handed bias for surface catalysis through many magnetic reversals. Magnetite contaminated with sulfur has already been proposed by Granick as a biopoetic site because it provides a weak source of chemical energy derived by photochemical conversion. Indirect evidence for this hypothesis has been provided by the molecular structure of ferredoxin - a single strand of the 14 primordial amino acids wrapped around an FeS core. Lava flows have been suggested as biopoetic sites by Fox, since their temperature and chemical composition might allow for the rapid synthesis of prebiotic compounds at the surface of the primitive earth. The additional fact that magnetite in lave flows also provides a persistent handed site for surface catalysis offers a further argument for the experimental investigation of this specific biopoetic environment.

Biological Evolution↗
PubMed1976

Polarized bremsstrahlung not the source of optical activity.

An evaluation is made of the previously proposed scheme (polarized beta-particles leads to circularly polarized bremsstrahlung leads to optically active molecules) by which dissymmetry at the elementary particle level may be transmitted to the molecular level. The calculations suggest that much too small a fraction of the total energy of the electron appears as light, capable of causing photochemical resolution, to explain results obtained in the laboratory on the preferential radiation-induced decomposition one enantiomer of chiral amino acids.

Amino Acids↗
PubMedDate not supplied

[Molecular computer. Biological physics and physics of the real world].

Any mind (man or computer) using Physical laws is a part of physical world, and thus it is necessary to correct physical laws for taking into account influence of the work of real limited computer on the predicted result. If we suppose that univerce was constructed to be supreme regular for mind, then this correction is negligible and on principle there is possibility to calculate relation between fundamental physical and biophysical constants. Two main principle are proposed: 1. The principle of minimum action and uncontrole influence of mind. 2. The maximum asymmetry of elementary particles, which are allowed by first principle. The first principle requires the upper and the lower limits for all physical values, and first of all the upper limit for velocity (c) and the lower limit for action (h). The second principle allows to construct the minimal physical elements for mind.

Biophysical Phenomena↗
PubMed1976

[Basic changes in neurons in the peripheral regions of the human nervous system during pathologic processes (electron microscopic study)].

Compensatory-adaptational and reparative reactions were studied in bodies, processes, receptors and synapses of the human peripheral nervous system and in the innervated substrate (myocardium, kidney, liver) by means of electron microscopy. An extreme increase of the electron density of macromolecular protein formations of specific elementary particles was revealed, in particular, in the outer layers of the hypertrophid mitochondria cryst membranes at 50000.000 magnification. These particles are considered as mitochondria precursors.

Cell Nucleus↗
PubMed1977

Particle radiation therapy: experimental basis and clinical application.

Conventional radiation therapy can eradicate cancers within tissues of their origin and regional spread with conservation of anatomic structure, thus preserving function and cosmesis. New treatment methods may improve the therapeutic ratio either by increasing the frequency of tumor control or lessening the treatment-related morbidity, or both. There are several physical and biological reasons why particle radiation therapy may increase tumor cell killing without increasing normal tissue sequelae. After preliminary basic research, clinical trials of fast neutron and proton teletherapy were started. Over 700 patients were treated with fast neutron beams in 3 U.S. research programs. These studies will be extended to include negative pi mesons and heavy particles.

Elementary Particles↗
PubMed1979

Sources of Atomic and Nuclear Data for Biomedical Purposes.

Users of nuclear and atomic data for biomedical purposes often have difficulty in identifying the most up-to-date and appropriate sources of such data. The biomedical Subcommittee of the UK Nuclear Data Committee have prepared a list of recommended data sources available at the beginning of 1978 on radioactive decay schemes; neutron cross-sections and data for neutron activation analysis; excitation functions for the production of radionuclides by charged particles; W-values for neutron and electron dosimetry; X- and gamma-ray cross-sections; stopping powers and ranges for charged particles; and dose deposition by electrons and beta particles.

Alpha Particles↗
PubMed1990

On the use of the pion stopping distribution and the lesion additivity concept for the calculation of effective doses in pion treatment planning.

The large spatial variation in LET, and hence in RBE, is one of the main obstacles in the development of routine treatment planning of charged particle beams. Since the biological effect distribution of plans cannot be realistically measured for each patient, a simple scheme of relating effect to basic empirical physical measurement is required. For the case of a pion beam, the high LET dose distribution is correlated with that of the pion stopping density, which can be indirectly measured using several techniques. A scheme based on this spatial correlation has been developed. In this method, after partitioning the local dose into a high and a low LET fraction, the local effective dose is computed using a simple formula extracted from a recent analysis of radiobiological results for mixtures of radiations of different LET. This simple formula can also be derived from a mechanistic model of mixed radiation action developed using the hypothesis of additivity of common intermediate lesions. In this paper, the concept of spatial correlation between the high LET dose and the pion stars is merged with the concept of lesion additivity for mixed radiation, from which a simple computational scheme is formulated for the calculation of effective doses in the treatment planning of pions. Similar schemes can also be developed for other charged particle beams.

Elementary Particles↗
PubMedDate not supplied

[A quantitative validation of the patterns determining the changes in higher nervous activity after irradiation with heavy charged particles under conditions of the influence of stress factors].

The major regularities that govern the alteration of the higher nervous activities after irradiation with heavy charged particles have been grounded quantitatively. The influence of the environmental factors on the exposed organism acquires a stress nature and is accompanied by the alteration of the central-central and central-peripheric relationships in major nervous processes whose pathogenesis is determined, to some extent, by a change in the homeostatic level of the synaptic energy transfer rate that depends quantitatively on the response of the irradiated organism at different stages of the development of radiation damage. The rate of the synaptic transfer at early periods of radiation damage development is 11.6, 9.7, and 12.4 (relative units) corresponding to the stages of radiation affection by heavy charged particles which permits to compare qualitatively and quantitatively the reactions of final acceptors of various executive morphofunctional structures after irradiation with heavy charged particles.

Animals↗