生物化学技术

Autofluorescent ceroid/lipofuscin-type pigments are usually classified and defined as follows: Lipofuscin is an intracellular, age-related, fluorescent, cytoplasmic, granular pigment. It is mainly present in secondary lysosomes of post-mitotic cells, such as neurons, ca ...

The technology of opening and resealing the erythrocytes can be used successfully to investigate several basic aspects of cellular metabolism, including oxidative metabolism. Human and animal erythrocytes can be loaded with different kinds of molecules (enzymes, metabolites, ...

Lipofuscin—a generic term applied to autofluorescent lipopigment—is a mixture of protein and lipid that accumulates in most aging cells, particularly those involved in high lipid turnover (e.g., the adrenal medula) or phagocytosis of other cell types (e g., the retinal pigment epitheli ...

Electron paramagnetic resonance (EPR) spectroscopy methodology is a highly selective and sensitive assay for detecting paramagnetic species. Owing to the unpaired electron in the outer orbit, free radicals are paramagnetic species and, when in sufficient quantity, are directly ...

Vesicular carriers represent a cellular entity involved in the transfer of proteins between different intracellular compartments. They were first identified and described by Jamieson and Palade (1) in their studies on the process of protein secretion in guinea-pig pancreas. Most of t ...

During his studies on the properties of oxygen, Priestley (1) noted that this gas, an essential ingredient for life processes, appears to “burn out the candle of life too quickly.” More than two centuries would elapse, however, before this observation would be associated with Grubb�’s (2) accounts ...

Free radicals generated by a wide variety of processes, such as ionizing radiation (1), toxic xenobiotics (2), inflammation (3), and metabolites of membrane lipid transformation (4), are involved in various diseases (5–9). A number of disorders in cellular and organ systems have been attribu ...

Recently the demand for the measurement of very low-light levels has been increasing in the fields of biology, chemistry, medicine, and many others; for instance, analytical chemistry needs to employ fluorescence, luminescence and Raman scattering light for the quantitative operat ...

Lipid hydroperoxides (LOOH) are the primary products of lipid peroxidation. Therefore, it would be desirable to detect and identify the lipid hydroperoxides in tissues or blood. One of the most advanced methods for the detection of LOOH is a chemiluminescence-based high-performance li ...

Reactive-oxygen species and organic free radicals are essential metabolic intermediates and have important regulatory functions. Overproduction of these reactive metabolites is implicated in the etiology of a host of degenerative diseases (1), such as cardiovascular disea ...

As is well-recognized, lipid peroxidation is initiated by the abstraction of a hydrogen atom from a polyunsaturated fatty acid, and proceeds via free-radical species to form the primary stable product, lipid hydroperoxide, and then the secondary stable product, lipid aldehyde, as depic ...

With the recognition that the imbalance between oxidant and antioxidant compounds is an important causative agent of aging and of various chronic diseases (1), there has been growing interest in elucidating the pathways involved in oxidative-stress initiation. As oxidative stress is ...

Epidemiological studies have confirmed that dietary supplementation with vitamin E significantly inhibits oxidation of low-density lipoproteins (1) and reduces the risk of atherosclerosis (2) and coronary heart disease (3). Retinol and β-carotene (β-caro) are important micr ...

The chemical composition of human blood plasma is widely studied and well-known, however, the exact nature of the antioxidants of plasma is very much open to dispute. The study of plasma antioxidants has been given a fresh stimulus in recent years by the development of new methods for the measurement ...

Tocopherols (vitamin E) are the major lipid-soluble chain-breaking antioxidants of membranes and blood plasma (1–3). Antioxidant function of tocopherols is confined to their chromanol nucleus with 6-hydroxy group, and is based on the ability of the latter to reduce different radicals ( ...

Enzymes play an important role in the production of radicals and their metabolism. Techniques to measure pro-oxidant conditions that generate radicals and end-products are described in various chapters throughout this book. The major defense enzymes are superoxide dismutase (SO ...

The protective “tone” of a tissue against oxidative stress depends on a balance between endogenous antioxidants (enzymatic and non-enzymatic) and the amount of pro-oxidant reactive oxygen lipid peroxides (1–3). Lipid and cholesterol peroxides are transported in lipoproteins (p ...

Oxidation of low-density lipoprotein (LDL) is of great interest for epidemiological and clinical diagnostic reasons, as well as for basic scientific research, because it is thought to precede the development of atherosclerotic lesions (1). Measurement of individual antioxidants ...

Free lipoic acid is present in biological systems at extremely low levels. The biological function of lipoic acid requires its covalent linkage to the N6-amino group of lysine residues of several proteins (1). The covalent attachment of lipoic acid to specific proteins is catalyzed by lipoate ...

Glutathione (GSH; L- -glutamyl-L-cysteinl-glycine) plays an important role in the prevention of radical mediated injury to the body. It does so as a radical scavenger and by supplying GSH to the antioxidant enzymes described in Chapter 29. In conjunction with superoxide dismutase (SOD), whi ...