Potential use of a novel actinobacterial species to ameliorate tungsten nanoparticles induced oxidative damage in cereal crops

Photodynamic treatment (PDT) is often successful when used against aerobic microbes, given their natural susceptibility to oxidative damage. To this end, the current study aimed to explore the photodynamic action of acetylsalicylic acid (ASA; aspirin, which is commonly used to treat non-infectious ailments), when administered to respiring cryptococcal cells. The treatment of cryptococcal cells, i.e., exposure to 0.5 or 1 mM of ASA in the presence of ultraviolet light (UVL) for 10 min, resulted in a significant (p < 0.05) reduction in the growth of tested cells when compared to non-treated (non-Rx) cells, i.e., no ASA and no UVL. The treated cells were also characterised by diseased mitochondria, which is crucial for the survival of respiring cells, as observed by a significant (p < 0.05) loss of mitochondrial membrane potential (ΔΨM) and significant (p < 0.05) accumulation of reactive oxygen species (ROS) when compared to non-Rx cells. Moreover, the photolytic products of acetylsalicylic acid altered the ultrastructural appearance of treated cells as well as limited the expression levels of the capsular-associated gene, CAP64, when compared to non-Rx cells. The results of the study highlight the potential use of ASA as a photosensitiser that is effective for controlling the growth of cryptococcal cells. Potentially, this treatment can also be used as an adjuvant, to complement and support the usage of current anti-microbial agents.

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The growth of mica polytypes as studied by conventional and high-resolution TEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100074690 ◽

1983 ◽

Vol 41 ◽

pp. 174-177

Author(s):

A. Baronnet ◽

M. Amouric

Keyword(s):

Water Pressure ◽

Point Of View ◽

Temperature Fields ◽

Natural Occurrence ◽

Growth Mechanisms ◽

Long Period ◽

High Resolution Tem ◽

Layer Stacking ◽

Experimental Works ◽

Potential Use

The origin of mica polytypes has long been a challenging problem for crystal- lographers, mineralogists and petrologists. From the petrological point of view, interest in this field arose from the potential use of layer stacking data to furnish further informations about equilibrium and/or kinetic conditions prevailing during the crystallization of the widespread mica-bearing rocks. From the compilation of previous experimental works dealing with the occurrence domains of the various mica "polymorphs" (1Mr, 1M, 2M1, 2M2 and 3T) within water-pressure vs temperature fields, it became clear that most of these modifications should be considered as metastable for a fixed mica species. Furthermore, the natural occurrence of long-period (or complex) polytypes could not be accounted for by phase considerations. This highlighted the need of a more detailed kinetic approach of the problem and, in particular, of the role growth mechanisms of basal faces could play in this crystallographic phenomenon.

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Erythrophagocytosis in the Liver in Hemolytic Anemias

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100100664 ◽

1968 ◽

Vol 26 ◽

pp. 184-185

Author(s):

O. T. Minick ◽

E. Orfei ◽

F. Volini ◽

G. Kent

Keyword(s):

Acid Phosphatase ◽

Oxidative Damage ◽

Phosphatase Activity ◽

Kupffer Cells ◽

Acid Phosphatase Activity ◽

Common Type ◽

Red Cell ◽

Cell Fragments ◽

Reticulo Endothelial System ◽

Important Site

Hemolytic anemias were produced in rats by administering phenylhydrazine or anti-erythrocytic (rooster) serum, the latter having agglutinin and hemolysin titers exceeding 1:1000.Following administration of phenylhydrazine, the erythrocytes undergo oxidative damage and are removed from the circulation by the cells of the reticulo-endothelial system, predominantly by the spleen. With increasing dosage or if animals are splenectomized, the Kupffer cells become an important site of sequestration and are greatly hypertrophied. Whole red cells are the most common type engulfed; they are broken down in digestive vacuoles, as shown by the presence of acid phosphatase activity (Fig. 1). Heinz body material and membranes persist longer than native hemoglobin. With larger doses of phenylhydrazine, erythrocytes undergo intravascular fragmentation, and the particles phagocytized are now mainly red cell fragments of varying sizes (Fig. 2).

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An atomic-resolution microscope study of Al contracts on GaAs

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100145005 ◽

1986 ◽

Vol 44 ◽

pp. 726-727

Author(s):

Z. Liliental-Weber ◽

C. Nelson ◽

R. Ludeke ◽

R. Gronsky ◽

J. Washburn

Keyword(s):

High Speed ◽

Schottky Contacts ◽

Detailed Knowledge ◽

The Past ◽

Semiconductor Interfaces ◽

Deposited Metal ◽

Microwave Applications ◽

Free Interfaces ◽

Potential Use

The properties of metal/semiconductor interfaces have received considerable attention over the past few years, and the Al/GaAs system is of special interest because of its potential use in high-speed logic integrated optics, and microwave applications. For such materials a detailed knowledge of the geometric and electronic structure of the interface is fundamental to an understanding of the electrical properties of the contact. It is well known that the properties of Schottky contacts are established within a few atomic layers of the deposited metal. Therefore surface contamination can play a significant role. A method for fabricating contamination-free interfaces is absolutely necessary for reproducible properties, and molecularbeam epitaxy (MBE) offers such advantages for in-situ metal deposition under UHV conditions

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