Femtosecond Dynamics Within the B820 Dimeric Subunit from the Core Antenna Complex of Rs. rubrum

Abstract The target article carefully describes the memory system, centered on the temporal lobe that builds specific memory traces. It does not, however, mention the laterality effects that exist within this system. This commentary briefly surveys evidence showing that clear asymmetries exist within the temporal lobe structures subserving the core system and that the right temporal structures mainly underpin face familiarity feelings.

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A scanning electron microscopic study on dissolving process of cholesterol gallstones by chenodeoxycholic acid (CDCA)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100083485 ◽

1978 ◽

Vol 36 (2) ◽

pp. 522-523

Author(s):

T. Kanetaka ◽

M. Cho ◽

S. Kawamura ◽

T. Sado ◽

K. Hara

Keyword(s):

Electron Microscope ◽

Chenodeoxycholic Acid ◽

Outer Surface ◽

Electron Microscopic ◽

Cholesterol Gallstones ◽

The Core ◽

Scanning Electron Microscopic Study ◽

Scanning Electron Microscopic ◽

Acceleration Voltage ◽

Scanning Electron

The authors have investigated the dissolution process of human cholesterol gallstones using a scanning electron microscope(SEM). This study was carried out by comparing control gallstones incubated in beagle bile with gallstones obtained from patients who were treated with chenodeoxycholic acid(CDCA).The cholesterol gallstones for this study were obtained from 14 patients. Three control patients were treated without CDCA and eleven patients were treated with CDCA 300-600 mg/day for periods ranging from four to twenty five months. It was confirmed through chemical analysis that these gallstones contained more than 80% cholesterol in both the outer surface and the core.The specimen were obtained from the outer surface and the core of the gallstones. Each specimen was attached to alminum sheet and coated with carbon to 100Å thickness. The SEM observation was made by Hitachi S-550 with 20 kV acceleration voltage and with 60-20, 000X magnification.

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The Structure and Development of Microbodies in the Fat Body and other Tissues of an Insect (Calpodes Ethlius)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010006773x ◽

1970 ◽

Vol 28 ◽

pp. 148-149

Author(s):

M. Locke ◽

J. T. McMahon

Keyword(s):

Electron Microscopy ◽

Liquid Crystals ◽

Fat Body ◽

Competitive Inhibitor ◽

Dense Core ◽

Urate Oxidase ◽

Blood Proteins ◽

Free Base ◽

The Core ◽

The Matrix

The fat body of insects has always been compared functionally to the liver of vertebrates. Both synthesize and store glycogen and lipid and are concerned with the formation of blood proteins. The comparison becomes even more apt with the discovery of microbodies and the localization of urate oxidase and catalase in insect fat body.The microbodies are oval to spherical bodies about 1μ across with a depression and dense core on one side. The core is made of coiled tubules together with dense material close to the depressed membrane. The tubules may appear loose or densely packed but always intertwined like liquid crystals, never straight as in solid crystals (Fig. 1). When fat body is reacted with diaminobenzidine free base and H2O2 at pH 9.0 to determine the distribution of catalase, electron microscopy shows the enzyme in the matrix of the microbodies (Fig. 2). The reaction is abolished by 3-amino-1, 2, 4-triazole, a competitive inhibitor of catalase. The fat body is the only tissue which consistantly reacts positively for urate oxidase. The reaction product is sharply localized in granules of about the same size and distribution as the microbodies. The reaction is inhibited by 2, 6, 8-trichloropurine, a competitive inhibitor of urate oxidase.

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Exsolution and inversion in pigeonite from the Whin Sill, Northern England

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100109513 ◽

1978 ◽

Vol 36 (1) ◽

pp. 474-475

Author(s):

P.P.K. Smith

Keyword(s):

High Temperature ◽

Low Temperature ◽

Homogeneous Nucleation ◽

Silicate Mineral ◽

Antiphase Boundaries ◽

Two Phase ◽

Primitive Form ◽

The Core ◽

Nucleation Mechanisms ◽

And Inversion

Grains of pigeonite, a calcium-poor silicate mineral of the pyroxene group, from the Whin Sill dolerite have been ion-thinned and examined by TEM. The pigeonite is strongly zoned chemically from the composition Wo8En64FS28 in the core to Wo13En34FS53 at the rim. Two phase transformations have occurred during the cooling of this pigeonite:- exsolution of augite, a more calcic pyroxene, and inversion of the pigeonite from the high- temperature C face-centred form to the low-temperature primitive form, with the formation of antiphase boundaries (APB's). Different sequences of these exsolution and inversion reactions, together with different nucleation mechanisms of the augite, have created three distinct microstructures depending on the position in the grain.In the core of the grains small platelets of augite about 0.02μm thick have farmed parallel to the (001) plane (Fig. 1). These are thought to have exsolved by homogeneous nucleation. Subsequently the inversion of the pigeonite has led to the creation of APB's.

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Intramitochondrial Viruses of Reptilian Cell Origin

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100094851 ◽

1972 ◽

Vol 30 ◽

pp. 318-319

Author(s):

Philip D. Lunger ◽

H. Fred Clark

Keyword(s):

Particle Production ◽

Outer Zone ◽

Density Variation ◽

Core Region ◽

Mitochondrial Membranes ◽

Virus Particles ◽

The Core ◽

Vipera Russelli ◽

Maturation Stages ◽

Type Particle

In the course of fine structure studies of spontaneous “C-type” particle production in a viper (Vipera russelli) spleen cell line, designated VSW, virus particles were frequently observed within mitochondria. The latter were usually enlarged or swollen, compared to virus-free mitochondria, and displayed a considerable degree of cristae disorganization.Intramitochondrial viruses measure 90 to 100 mμ in diameter, and consist of a nucleoid or core region of varying density and measuring approximately 45 mμ in diameter. Nucleoid density variation is presumed to reflect varying degrees of condensation, and hence maturation stages. The core region is surrounded by a less-dense outer zone presumably representing viral capsid.Particles are usually situated in peripheral regions of the mitochondrion. In most instances they appear to be lodged between loosely apposed inner and outer mitochondrial membranes.

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Bonafide Substructure in the Core of Ferritin

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100118485 ◽

1985 ◽

Vol 43 ◽

pp. 322-323

Author(s):

William H. Massover

Keyword(s):

Phase Contrast ◽

Central Cavity ◽

Amplitude Image ◽

Ultrastructural Studies ◽

The Core ◽

Hydrated Ferric Oxide ◽

Imaging Artifact ◽

Contrast Image ◽

Protein Shell ◽

Regular Patterns

Each molecule of ferritin (d = 130Å) contains a core of iron surrounded by a 24-subunit protein shell. The amount of iron stored is variable and is present within the central cavity (d = 80Å) as a hydrated ferric oxide equivalent to the mineral, ferrihydrite. Many early ultrastructural studies of ferritin detected regular patterns of a multiparticulate substructure in the iron-rich core [e.g., 3,4], Each small particle was termed a “micelle“; a theory became widely accepted that a core consisted of up to six micelles positioned at the vertices of an octahedron. Other workers recognized that the apparent micelles were smaller or even disappeared if images were recorded closer to exact focus [e.g., 5]. In 1969, Haydon clearly established that the observed substructure was really an imaging artifact; each apparent micelle was only a dot in the underfocused phase contrast image of the supporting film superimposed on the amplitude image of the strongly scattering metal.

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