THE EMPLOYMENT OF GLUCAN AND GLUCAN ACTIVATED MACROPHAGES IN THE ENHANCEMENT OF HOST RESISTANCE TO MALIGNANCIES IN EXPERIMENTAL ANIMALS

Fungi have been studied as prototype activators of the complement cascade since the early 1900s. More recently, attention has focused on the role of the complement system in the pathogenesis of fungal infections. The interactions of Cryptococcus neoformans and Candida albicans with the complement system are the most widely characterized; however, all pathogenic fungi examined to date have the ability to initiate the complement cascade. The molecular mechanisms for initiation and regulation of the complement cascade differ from one fungus to another, most likely reflecting differences in the structure of the outer layers of the cell wall. The molecular bases for such differences remain to be identified. Studies of mycoses in experimental animals with induced or congenital deficiencies in the complement system demonstrate that complement is an important innate system for control of fungal infection. Contributions to host resistance include opsonization and generation of inflammatory mediators. Inflammation induced by chemotactic products of the complement system may contribute to the pathogenesis of some fungal infections.

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IN-SITU ACTIVATED MACROPHAGES ARE INVOLVED IN HOST-RESISTANCE TO LYMPHOMA METASTASIS BY PRODUCTION OF NITRIC-OXIDE

International Journal of Oncology ◽

10.3892/ijo.7.1.33 ◽

1995 ◽

Author(s):

V UMANSKY ◽

M ROCHA ◽

A KRUGER ◽

P VONHOEGEN ◽

V SCHIRRMACHER

Keyword(s):

Nitric Oxide ◽

Host Resistance ◽

Activated Macrophages

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Health Effects of Ozone Depletion

Journal of the American College of Toxicology ◽

10.3109/10915818909018068 ◽

1989 ◽

Vol 8 (6) ◽

pp. 1083-1089 ◽

Cited By ~ 1

Author(s):

Margaret L. Kripke

Keyword(s):

Ultraviolet Radiation ◽

Human Health ◽

Host Resistance ◽

Ozone Depletion ◽

Stratospheric Ozone ◽

Aquatic Life ◽

Experimental Animals ◽

Skin Cancers ◽

Theoretical Hypothesis ◽

Biologic System

The problem of ozone depletion has recently become a topic of major concern. What was once a vague, theoretical hypothesis that artificial chlorofluorocarbon compounds could accumulate in the stratosphere and break down ozone molecules is an imminent reality. A decrease in the concentration of stratospheric ozone would increase the amount of ultraviolet radiation in ambient sunlight. In addition to altering plant and aquatic life in unpredictable ways, increiased ultraviolet radiation will adversely affect human health. The incidence of various types of skin cancers will increase, as will the rate of deaths from skin cancer. In addition, there will be an increase in the occurrence of certain types of ocular cataracts. The most recently described effect of ultraviolet radiation on a biologic system is its ability to alter the immune system in experimental animals and humans. Although much is known about the immunologic effects of ultraviolet radiation, particularly in animal models, little information is available on its potential to decrease host resistance to infectious diseases. This is an important topic that needs to be addressed in order for us to understand fully the consequences of ozone depletion for human health.

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Analytical Electron Microscopy (AEM) of Meningeal Cells Exposed to Particulate Cobalt During Studies of Experimental Epilepsy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100053590 ◽

1982 ◽

Vol 40 ◽

pp. 186-187

Author(s):

R.G. Frederickson ◽

R.G. Ulrich ◽

J.L. Culberson

Keyword(s):

Electron Microscopy ◽

Analytical Electron Microscopy ◽

Experimental Epilepsy ◽

Metallic Cobalt ◽

Experimental Animals ◽

X Ray ◽

Brain Surface ◽

Meningeal Cells ◽

Analytical Electron ◽

The Brain

Metallic cobalt acts as an epileptogenic agent when placed on the brain surface of some experimental animals. The mechanism by which this substance produces abnormal neuronal discharge is unknown. One potentially useful approach to this problem is to study the cellular and extracellular distribution of elemental cobalt in the meninges and adjacent cerebral cortex. Since it is possible to demonstrate the morphological localization and distribution of heavy metals, such as cobalt, by correlative x-ray analysis and electron microscopy (i.e., by AEM), we are using AEM to locate and identify elemental cobalt in phagocytic meningeal cells of young 80-day postnatal opossums following a subdural injection of cobalt particles.

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Ultrastructure and analytical microprobe analysis of simian lung mite pigments

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100143249 ◽

1986 ◽

Vol 44 ◽

pp. 324-325

Author(s):

R. W. Cole ◽

J. C. Kim

Keyword(s):

Biomedical Research ◽

Tissue Damage ◽

Microprobe Analysis ◽

Old World Monkeys ◽

Old World ◽

Experimental Animals ◽

The Past ◽

Lung Mite ◽

Mite Infestations ◽

Cardiopulmonary System

In recent years, non-human primates have become indispensable as experimental animals in many fields of biomedical research. Pharmaceutical and related industries alone use about 2000,000 primates a year. Respiratory mite infestations in lungs of old world monkeys are of particular concern because the resulting tissue damage can directly effect experimental results, especially in those studies involving the cardiopulmonary system. There has been increasing documentation of primate parasitology in the past twenty years.

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Tobacco Mosaic Virus-Infected Tissue

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100119375 ◽

1985 ◽

Vol 43 ◽

pp. 510-511

Author(s):

Egbert W. Henry

Keyword(s):

Nicotiana Tabacum ◽

Tobacco Mosaic Virus ◽

Chlorogenic Acid ◽

Mosaic Virus ◽

Host Resistance ◽

Oxidative Metabolism ◽

Leaf Tissue ◽

Vein Clearing ◽

Basal Septum ◽

Concentration Levels

Tobacco mosaic virus (TMV) infection has been studied in several investigations of Nicotiana tabacum leaf tissue. Earlier studies have suggested that TMV infection does not have precise infective selectivity vs. specific types of tissues. Also, such tissue conditions as vein banding, vein clearing, liquification and suberization may result from causes other than direct TMV infection. At the present time, it is thought that the plasmodesmata, ectodesmata and perhaps the plasmodesmata of the basal septum may represent the actual or more precise sites of TMV infection.TMV infection has been implicated in elevated levels of oxidative metabolism; also, TMV infection may have a major role in host resistance vs. concentration levels of phenolic-type enzymes. Therefore, enzymes such as polyphenol oxidase, peroxidase and phenylalamine ammonia-lyase may show an increase in activity in response to TMV infection. It has been reported that TMV infection may cause a decrease in o-dihydric phenols (chlorogenic acid) in some tissues.

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