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PubMed1964

A MACROMOLECULAR REPEATING UNIT OF MITOCHONDRIAL STRUCTURE AND FUNCTION. CORRELATED ELECTRON MICROSCOPIC AND BIOCHEMICAL STUDIES OF ISOLATED MITOCHONDRIA AND SUBMITOCHONDRIAL PARTICLES OF BEEF HEART MUSCLE.

A repeating particle associated with the cristae and the inner membrane of the external envelope has been recognized and characterized in beef heart mitochondria by correlated electron microscopic and biochemical studies. Many thousands (ca. 10(4) to 10(5)) of these particles, disposed in regular arrays, are present in a single mitochondrion. The repeating particle, called the elementary particle (EP), consists of three parts: (1) a spherical or polyhedral head piece (80 to 100 A in diameter); (2) a cylindrical stalk (about 50 A long and 30 to 40 A wide); and (3) a base piece (40 x 110 A). The base pieces of the elementary particles form an integral part of the outer dense layers of the cristae. The elementary particles can be seen in electron micrographs of mitochondria in situ, of isolated mitochondria, and of submitochondrial particles with a complete electron transfer chain. Negative staining with phosphotungstate is only one of several techniques that can be used for reproducible demonstration of the repeating particles and underlying subunit organization of mitochondrial membranes. A particulate unit containing a complete electron transfer chain can be isolated from beef heart mitochondria. The isolated unit approximates in size that of the elementary particle in situ. The molecular weight of the particle in situ is calculated to be 1.3 x 10(6). Evidence is presented for identifying the isolated unit with the elementary particle visualized in situ. The elementary particle of the mitochondrion is believed to be a prototype of a class of functional particles or macromolecular assemblies of similar size found in association with membranes generally.

Animals↗
PubMed1989

Triton,... electron,... cosmon,...: An infinite regression?

I propose an elementary particle model in which the simplest near-Dirac particles triton, proton, and electron are members of the three top layers of a bottomless stack. Each particle is a composite of three particles from the next layer below in an infinite regression approaching Dirac point particles. The cosmon, an immensely heavy lower layer subquark, is the elementary particle. The world-atom, a tightly bound cosmon/anticosmon pair of zero relativistic total mass, arose from the nothing state in a quantum jump. Rapid decay of the pair launched the big bang and created the universe.

Journal Article↗
PubMed1996

[Wilhelm Conrad Röntgen and the discovery of X-rays].

W.C. Röntgen reported the discovery of X-rays in December 1895 after seven weeks of assiduous work during which he had studied the properties of this new type of radiation able to go through screens of notable thickness. He named them X-rays to underline the fact that their nature was unknown. The news of this discovery immediately aroused an immense interest in the public and also initiated intense research in several directions. Physicians and physicists began as early as January 1896 to use X-rays on patients to investigate the skeleton and subsequently the lung and other organs. This was the birth or radiology. Rapidly they observed skin erythema, which led to the idea of using X-rays against a variety of lesions. In June 1896 the first patient was treated by radiotherapy. J.J. Thomson (Cambridge, U.K.) showed that X-rays were able to ionize gaz and the study of this phenomenon led to the discovery of electrons in 1897. In order to understand the emission of X-rays, H. Becquerel (Paris) investigated the role of the phosphorescence of the glass of the tube and while doing so discovered radioactivity in March 1896. X-rays and radioactivity were at the origin of the scientific revolution at the end of the 19th and the beginning of the 20th centuries. Research on radioactive materials demonstrated the existence of atoms which had been till then only a convenient hypothesis for explaining chemical reactions, but whose reality was considered as dubious by most physicists. Moreover, interaction of particles emitted by radionuclides and atoms enabled first the study of the structure of the atom and subsequently its nucleus. Matter, elements which were thought to be immutable were found to be transmutable, and eventually to disintegrate. The origin of the energy transferred to the radiation which was emitted appeared as a mystery and in order to explain it the physicist had to accept that matter could convert energy. In 1903 Einstein established the equivalence between matter and energy. Matter, energy, electricity, light which were formerly considered as continuous quantities were found to be discrete: there are particles of matter (elementary particles), energy (quanta, Planck 1905), electricity (electron), light (photons). Radioactive decay, particle interactions imposed a probabilistic physics which progressively replaced classic deterministic physics. Radioactivity can be used as a clock to measure time in the universe. Datations were made for fossils, art masterpieces and also for the earth, the solar system and universe. X-rays diffraction proved to be a powerful tool for studying crystals and molecules, in particular protein, and in 1953 enabled to demonstrate the DNA double helix. Hence X-rays and radioactivity originated a revolution in physics and science and in the vision of nature. The imperceptible and yet so powerful rays demonstrated the deficiencies of our senses. Mathematical entities and instrumentation must complement our sensations. The huge increment in our knowledge is accompanied by a divorce between the scientist and the layman who now often has great difficulties understanding new concepts not only in physics but also in biology.

Germany↗
PubMed2003

[From physics to biology: the intrinsic dynamics of the cosmos].

The History of Universe is described in an extremely summarized manner through the use of graphics, from Big bang until today. This is done according to the most recent standard models of Cosmology and Physics of elementary particles; in other words, according to those fields in Physics of a presupposed universal reference. The History of Life is immersed in this universal physical context, in a frame where our knowledge from Geology and Biology can be only terrestrial. The underlying ideas we try to arise are: 1) the transition from a relatively elementary structure to a posterior and a relatively more complex one requires some very special "environmental" conditions; and 2) the new structure can not be described only through its materic constituents, because in cosmic dynamicity new structures and new relationships (of intrinsic respectivity) arise, together with new laws (of extrinsic respectivity). Consequently and as an objective, physical knowledge (for example, elementary particles or atoms) alone in no way can explain biological reality (for example, cell or man).

Biology↗
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↗
PubMed1967

Studies of the mitochondrial energy-transfer system of brown adipose tissue.

An investigation of the mechanisms of norepinephrine action and heat production in brown adipose tissue from newborn rabbits has been carried out. Data obtained with the use of biochemical techniques has been correlated with morphological data from electron microscopy. Norepinephrine was found to stimulate the respiration of brown fat in vitro. Inhibitors of glycolysis abolish this effect, whereas inhibitors of oxidative phosphorylation do not, at least not to the same extent. Brown fat is readily permeable to added Krebs cycle intermediates. Substrate level phosphorylation, but no electron transport-coupled phosphorylation, could be demonstrated in isolated mitochondria. It is suggested that the rate of fatty acid oxidation is limited by the availability of phosphate acceptor systems which break down ATP formed at the substrate level and thus provide ADP for further substrate level phosphorylation. The theory of respiratory control by the action of reesterification of fatty acids is discussed in the light of these findings. Under the electron microscope, brown fat mitochondria are characterized by their large size, tightly packed cristae, and by the different types of granules in the matrix. No elementary particles are seen when the mitochondria are examined by the negative-staining technique. The absence of electron transport-coupled phosphorylation together with the apparent absence of elementary particles seems to be of particular significance.

Adenine Nucleotides↗
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↗
PubMed2006

Astroparticle physics and cosmology.

Astroparticle physics is an interdisciplinary field that explores the connections between the physics of elementary particles and the large-scale properties of the universe. Particle physicists have developed a standard model to describe the properties of matter in the quantum world. This model explains the bewildering array of particles in terms of constructs made from two or three quarks. Quarks, leptons, and three of the fundamental forces of physics are the main components of this standard model. Cosmologists have also developed a standard model to describe the bulk properties of the universe. In this new framework, ordinary matter, such as stars and galaxies, makes up only around 4% of the material universe. The bulk of the universe is dark matter (roughly 23%) and dark energy (about 73%). This dark energy drives an acceleration that means that the expanding universe will grow ever larger. String theory, in which the universe has several invisible dimensions, might offer an opportunity to unite the quantum description of the particle world with the gravitational properties of the large-scale universe.

Astronomical Phenomena↗
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↗
PubMed1997

The atomic basis of biological symmetry and periodicity.

Geometric derivations and mathematical formulas have shown how the symmetrical patterns of plants, animals and crystals, follow similar mathematical solutions. These transformations have had the great value of indicating relationships between different types of patterns. However, they could neither shed light on the material processes that led to the emergence of symmetries in nature, nor explain their transfer to higher levels of organization, as evolution proceeded from simple molecular systems to complex living organisms. Several phenomena contribute to elucidate the material processes that have led to the emergence and transfer of symmetries. Their characteristics can be summarized: (1) symmetries are inherent to the structure of matter, since they already occur in the elementary particles, such as the neutrino; (2) simple atoms, such as oxygen and hydrogen produce a six-ray symmetry in water crystals a pattern from which these crystals cannot depart; (3) the mechanism of twinning, common in minerals, obliges several components to associate in a regular fashion guided by the properties of their atoms; (4) the symmetries of crystals are decided by the electronic properties of their constituent atoms. Since living organisms consist of the same atoms that are found in the minerals, it is not surprising that the symmetries of the minerals were transferred intact to the cell and organism levels; (5) another atomic property that has been preserved is periodicity. The existence of the Periodic Table of the elements shows how this phenomenon is so well established at the atomic level. This periodicity was also transferred to the living organism level. Both biological structures and functions display periodicity; (6) the recurrence of the same type of symmetry in minerals, plant organs and animal structures is an expression of the preservation of this periodicity; (7) another manifestation of the periodicity is found in the recurrence of the same symmetry in flowers of a large number of plant families which are not closely related in evolutionary terms; (8) the re-emergence of the same symmetry at different levels of organization is also elucidated by the fact that different atom combinations can display the same form and even the same function. This is what has been called molecular mimicry. Examples are the minerals with quite different chemical compositions which display the same symmetry and the proteins, that although they consist of different amino acid sequences, result in the same structural pattern and the same function. Due to the occurrence of molecular mimicry, in the cell's main macromolecules, an organism does not even need to have the same genes to exhibit a symmetry that appeared long ago in evolution; and (9) support for the concept that the biological periodicity is anchored on the chemical periodicity is found, among other features, on the fact that the six atoms that build the main macromolecules of the cell: the nucleic acids and proteins are all simple atoms that are located in a 'niche' on the right side of the Periodic Table of the chemical elements. The basis of biological symmetry and periodicity is now starting to be elucidated in atomic terms.

Anatomy, Comparative↗
PubMed2000

Magnetic trapping of neutrons

Accurate measurement of the lifetime of the neutron (which is unstable to beta decay) is important for understanding the weak nuclear force and the creation of matter during the Big Bang. Previous measurements of the neutron lifetime have mainly been limited by certain systematic errors; however, these could in principle be avoided by performing measurements on neutrons stored in a magnetic trap. Neutral-particle and charged-particle traps are widely used for studying both composite and elementary particles, because they allow long interaction times and isolation of particles from perturbing environments. Here we report the magnetic trapping of neutrons. The trapping region is filled with superfluid 4He, which is used to load neutrons into the trap and as a scintillator to detect their decay. Neutrons in the trap have a lifetime of 750(+330)(-200) seconds, mainly limited by their beta decay rather than trap losses. Our experiment verifies theoretical predictions regarding the loading process and magnetic trapping of neutrons. Further refinement of this method should lead to improved precision in the neutron lifetime measurement.

Journal Article↗
PubMed1992

In search of a physical theory of time.

The variable time considered in science is a measurement. The relation of time to other variables is expressed in rates, and the variable time is seldom explicitly included in equations describing chemical reactions or radioactive decays. Recalling that the Greek word atom is applicable to indivisible particles in both spatial and temporal worlds, the term chronon is proposed to designate elementary particles of time in parallel to the atom in space. Considerations of interactions of chronons with material and nonmaterial objects could promote understanding of several paradoxes in physical and biological sciences.

Journal Article↗