Toxins endotoxins

Aetiology This coagulation disorder may occur in the course of a variety of diseases and clinical conditions. Aetiopathological possibilities include infections, toxins, endotoxins, dehydration, acidosis, antigen-antibody complexes or stasis of the blood flow as well as the tumour necrosis factor. 

Fever Fever often occurs for the most part, it remains at 38 °C, but septic temperatures are possible. In some cases, this may well be a question of aetiocholanolone fever, whereby aetiocholanolone can also be quantified in the serum. Bacterial infections are likewise a cause of fever and require appropriate treatment. Toxins may also be responsible for the febrile condition (tissue toxins, endotoxins), (s. p. 738)... 

The tonsils are part of the lymphatic system (they help prevent toxins from entering your body), as are the spleen and thymus. The lymphatic system handles toxins that enter your body from external sources, such as food or air pollution, but also deals with internally produced toxins (endotoxins), such as in inflammation, that are the result of normal metabolic processes. It carries acid waste products via lymph fluid, which enters your veins (and thus your bloodstream) near your heart. Once toxins have been swept up and dumped into the bloodstream, the kidneys and liver take over to filter them out of the blood. 

In the following, we will focus on in vitro tests for cell compatibility and blood compatibility. In this context, we will also discuss ISO 10993-5 (tests for in vitro cytotoxicity) and ISO 10993-4 (selection of tests for interactions with blood). Finally, the risk of pyrogens in the biomaterial context, especially of bacterial toxins (endotoxins), will be briefly highhghted and selected methods for determining pyrogens/endotoxins (cf. also ISO 10993-11) will be presented. 

Endotoxin A toxin produced by bacteria. The toxin is present in the environment only after death of the bacteria. 

B. thurigiensis is a common Gram-positive, spore-forming soil bacterium that produces inclusion bodies, microcrystalline clusters of many different proteins. These crystalline proteins, called 5-endotoxins, are the ion channel toxins that are sold commercially for pest control. Most such endotoxins are protoxins, which are inactive until cleaved to smaller, active proteins by proteases in the gut of a susceptible insect. One such crystalline protoxin. 

Other toxins that show low lethal toxicity to laboratory test animals include lipopolysaccharide endotoxin produced as part of the cell wall by all cyanobacteria 11) and certain toxins of some cyanobacteria suspected of causing contact irritation in recreational water supplies 4,12 Carmichael and Codd, unpublished results). 

Damage to the host may arise in two ways. First, multiplication of the microorganisms may cause mechanical damage to the tissue cells through interference with the normal cell metabolism, as seen in viral and some bacterial infections. Second, a toxin associated with the microorganism may adversely affect the tissues or organs of the host. Two types of toxins, called exotoxins and endotoxins, are associated with bacteria. 

The second B. thuringiensis toxin, the /3-exotoxin has a much broader spectrum encompassing the Lepidoptera, Coleoptera and Diptera. It is an adenine nucleotide, probably an ATP analogue which acts by competitively inhibiting enzymes which catalyse the hydrolysis of ATP and pyrophosphate. This compound, however, is toxic when administered to mammals so that commercial preparations of the B. thuringiensis 5-endotoxin are obtained from strains which do not produce the j8-exotoxin. 

Taylor, M. J. et al. Increased endotoxin sensitivity following T-2 toxin treatment is associated with increased absorption of endotoxin. Toxicol. Appl. Pharmacol. 109, 51, 1991. 

Endotoxin A toxin produced in an organism and liberated only when the organism disintegrates. 

Endotoxin. A heat-stable bacterial toxin not freely liberated into the surrounding medium. Endotoxins are released only when the integrity of the cell wall is disturbed, are less potent than most exotoxins, are less specific, and do not form toxoids. When injected in large quantities, endotoxins produce hemorrhagic shock and severe diarrhea. Smaller amounts cause fever, altered resistance to bacterial infections, leukopenia followed by leukocytosis, and numerous other biological effects. 

These are produced by addition of formalin to the toxin of microorganisms and incubating them at 37°G for three to four weeks. Gertain microorganisms produce endotoxins e.g. tetanus and diphtheria. The toxins produced by these organism are detoxicated and used for the preparation of vaccine. The toxoids have lost their toxicity but antigenicity is retained. 

Bacterial enck)toxin pass the water through a pyrogenic connection for about 1 minute and then collect the sample in a pyrogenic bottle. All materials coming in contact with test materials and reagents must be pyrogen free and careful technique is essential to prevent contamination with environmental endotoxin. 

Different subspecies have been shown to be active against different orders of insect. Although the method of insect death is the same, the different endotoxins either have different binding regimes or are activated by the gut enzymes of different insect species and this leads to the differences in activity spectrum. There is evidence, however, that different insect orders act upon the delta-endotoxins in different ways. Treatment of a pro-toxin with lepidopteran gut juice leads to a toxin that is active against Lepidoptera whereas treatment with dipteran gut juice produces... 

A link between bacteria and tumor therapy was found early, at the beginning of the XVIII century [10]. By the end of the XIX century, Coley [11] developed a treatment for cancer with a mixture of bacterial toxins. In 1943 Shear and Turner [4] found that the antitumor effect of Coley s toxin was due to endotoxins, and after several decades it was shown that the biological activity of LPS was due to the lipid A [5]. We investigated the structures of lipids A with regard to their antitumor activities [12], finding that the optimum in vivo activity is obtained with diglucosamines acylated by 3 long chain fatty acids. 

Inhibitors/Toxins Trypsin inhibitors, aflatoxins, exotoxins (botulinum), endotoxins, PCBs, vomitoxin... 

Robbins PW, Wright A (1971) in Weinbaun G, Kadis S, Ajl SJ (eds) Microbial toxins, Vol IV Bacterial endotoxins Academic Press New York p 351... 

Endotoxin was initially described in the 19th century, but became the subject of intensive investigation since the 1920s. The clinical syndrome of Gram-negative bacterial sepsis was not described until the early 1950s (Waisbren, 1951). The focus on endotoxin as a critical initiator of sepsis occurred in large part because of a serendipitous confluence of events an attempt to understand the mechanism of action of endotoxin as a component of Coley s toxin used to treat cancer and the... 

Where the compounding is nonaseptic, careful control over the environment, materials, and equipment is still appropriate to reduce viable/nonviable levels and to reduce the potential for endotoxin. Time limits should be imposed on manufacturing operations for additional control over microorganisms and thus microbial toxins. 

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