Escherichia coliDnaA forms helical structures along the longitudinal cell axis distinct from MreB filaments

The fine structure of the cell wall of both ray and vertical parenchyma has been investigated. In all species examined secondary thickening had occurred. In the primary cell wall the micellar orientation was approximately trans"erse to the longitudiJ)aI cell axis. Using optical and X-ray methods the secondary cell wall was shown to possess a helical micellar organization, the micelles being inclined between 30� and 60� to the longitudinal cell axis.

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The opening and shedding mechanism of the female cones of Pinus radiata

Australian Journal of Botany ◽

10.1071/bt9640125 ◽

1964 ◽

Vol 12 (2) ◽

pp. 125 ◽

Cited By ~ 22

Author(s):

R Allen ◽

AB Wardrop

Keyword(s):

Pinus Radiata ◽

Radial Growth ◽

Secondary Wall ◽

Vascular Tissue ◽

Middle Layer ◽

Cell Axis ◽

Vascular Connection ◽

Differential Shrinkage ◽

Longitudinal Cell ◽

Cone Scale

The opening of the female cones of P. radiata has been shown to result from differential shrinkage between the adaxial vascular tissue and the abaxial sclerenchyma of the cone scale. The organization of the secondary wall of the tracheids typically consists of three helically organized concentric layers. In the outer and inner layers the microfibrillar orientation is approximately transverse, and in the middle layer the helix makes an angle of c. 40° with the longitudinal cell axis. In the sclerenchyma the secondary wall consists of wide layers in which the microfibrils of the lamellae are almost transverse to the longitudinal cell axis, alternating with narrow layers in which the microfibrils of the lamellae are almost parallel to the cell axis. Opening is preceded by a severance of the vascular connection between the cone and the stem or branch by the occlusion of the lurnina of the tracheids of the peduncle with resin. As radial growth of the stem proceeds, small fissures develop between the xylem of the stem or branch and that of the cone peduncle. The fissures become filled with resin and there is a progressive erosion of the tracheids of the peduncle until ultimately the xylem of the peduncle is separated from that of the stem or branch.

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Cell Wall Organization and the Properties of the Xylem 1. Cell Wall Organization and the Variation of Breaking Load in Tension of the Xylem in Conifer Stems

Australian Journal of Biological Sciences ◽

10.1071/bi9510391 ◽

1951 ◽

Vol 4 (4) ◽

pp. 391 ◽

Cited By ~ 9

Author(s):

ABW Ardrop

Keyword(s):

Cell Wall ◽

Basic Density ◽

Breaking Load ◽

Cellulose Content ◽

Micellar System ◽

Growth Rings ◽

Cell Axis ◽

Tracheid Length ◽

Cell Wall Organization ◽

Longitudinal Cell

The variation of breaking load in tension of tangential longitudinal sections of wood, taken from successive growth rings of each of six conifer stems, has been studied. An increase in this property was observed in successive growth rings from the stem centre of each specimen. This was paralleled by an increase in tracheid length, basic density, and cellulose content. The inclination to the longitudinal cell axis of the spiral micellar system of the cell wall decreased with increasing tracheid length.

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Studies of a Defective Measles Virus

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100100780 ◽

1968 ◽

Vol 26 ◽

pp. 208-209

Author(s):

R. M. McCombs ◽

M. Benyesh-Melnick ◽

J. P. Brunschwig

Keyword(s):

Inclusion Bodies ◽

Measles Virus ◽

Giant Cells ◽

Helical Structures ◽

Thin Sections ◽

Virus Particles ◽

Extracellular Virus ◽

Culture Cells ◽

Infected Cells ◽

Eosinophilic Inclusions

Measles virus is an agent that is capable of replicating in a number of different culture cells and generally causes the formation of multinucleated giant cells. As a result of infection, virus is released from the cells into the culture fluids and reinfection can be initiated by this cell-free virus. The extracellular virus has been examined by negative staining with phosphotungstic acid and has been shown to be a rather pleomorphic particle with a diameter of about 140 mμ. However, no such virus particles have been detected in thin sections of the infected cells. Rather, the only virus-induced structures present in the giant cells are eosinophilic inclusions (intracytoplasmic or intranuclear). These inclusion bodies have been shown to contain helical structures, resembling the nucleocapsid observed in negatively stained preparations.

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Epitaxy and texture analysis of Bi-Sr-Ca-Cu-O thin films on (100) MgO using Transmission Electron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100173479 ◽

1990 ◽

Vol 48 (4) ◽

pp. 68-69

Author(s):

J. T. Sizemore ◽

D. G. Schlom ◽

Z. J. Chen ◽

J. N. Eckstein ◽

I. Bozovic ◽

...

Keyword(s):

Electron Microscopy ◽

Thin Films ◽

Transmission Electron Microscopy ◽

Critical Currents ◽

Unit Cell ◽

X Ray Diffraction ◽

Cell Axis ◽

Transmission Electron ◽

Synthesis Procedure

Investigators observe large critical currents for superconducting thin films deposited epitaxially on single crystal substrates. The orientation of these films is often characterized by specifying the unit cell axis that is perpendicular to the substrate. This omits specifying the orientation of the other unit cell axes and grain boundary angles between grains of the thin film. Misorientation between grains of YBa2Cu3O7−δ decreases the critical current, even in those films that are c axis oriented. We presume that these results are similar for bismuth based superconductors and report the epitaxial orientations and textures observed in such films.Thin films of nominally Bi2Sr2CaCu2Ox were deposited on MgO using molecular beam epitaxy (MBE). These films were in situ grown (during growth oxygen was incorporated and the films were not oxygen post-annealed) and shuttering was used to encourage c axis growth. Other papers report the details of the synthesis procedure. The films were characterized using x-ray diffraction (XRD) and transmission electron microscopy (TEM).

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Adipokines as key players in β cell function and failure

Clinical Science ◽

10.1042/cs20190523 ◽

2019 ◽

Vol 133 (22) ◽

pp. 2317-2327 ◽

Cited By ~ 3

Author(s):

Nicolás Gómez-Banoy ◽

James C. Lo

Keyword(s):

Metabolic Diseases ◽

Cell Function ◽

Whole Body ◽

Pancreatic Β Cell ◽

Β Cell ◽

Cell Axis ◽

Β Cell Function ◽

Prevalence Of Obesity ◽

Specific Factors ◽

Whole Body Metabolism

Abstract The growing prevalence of obesity and its related metabolic diseases, mainly Type 2 diabetes (T2D), has increased the interest in adipose tissue (AT) and its role as a principal metabolic orchestrator. Two decades of research have now shown that ATs act as an endocrine organ, secreting soluble factors termed adipocytokines or adipokines. These adipokines play crucial roles in whole-body metabolism with different mechanisms of action largely dependent on the tissue or cell type they are acting on. The pancreatic β cell, a key regulator of glucose metabolism due to its ability to produce and secrete insulin, has been identified as a target for several adipokines. This review will focus on how adipokines affect pancreatic β cell function and their impact on pancreatic β cell survival in disease contexts such as diabetes. Initially, the “classic” adipokines will be discussed, followed by novel secreted adipocyte-specific factors that show therapeutic promise in regulating the adipose–pancreatic β cell axis.

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