Bacterial detection

Culture of intestinal contents is the gold standard for detecting bacterial overgrowth [2, 7, 9], This technique allows both segmental localization and the identification required to distinguish between URT and Gram-negative bacilli, respectively. The labor intensity and cost, however, make its clinical use difficult. 

The chemical industry contacts supply chains, such as those for construction materials, automotive materials, and food, at multiple points. We can clean, disinfect, and genetically engineer seed. We can provide advanced coatings and packaging materials, as well as systems to detect bacterial contamination and spoilage. Can we make supply chains safer ... 

Sterility testing is designed to detect bacterial contamination. Although viruses and other small microorganisms will pass through filters they are not usually tested for unless the product has a special requirement that demands this additional testing. 

Each lot of media must pass a growth promotion test (10 to 100 CFUs per container) following the media fill run and again after the end of the incubation period. Typically incubation of media involves a period of 7 days at 30-35°C to detect bacterial growth, followed by 7 days at 20-25°C for molds. Incubation conditions must be justified based on favored growth conditions for common environmental isolates. Prior to incubation, each unit must be inspected, with any leaking or damaged units removed. Each unit also must be rolled or inverted prior to incubation for media to contact all interior surfaces of the container. 

Besides glucose, other analytes of clinical value can be possibly quantified by noninvasive spectral analysis. In vivo concentrations of lactate and urea are examples. The concentration of lactate in blood is used clinically to follow intensive care treatments, to identify cardiac or liver failure, to determine hypoxia of tissues from atherosclerosis, and to detect bacterial infection. In vivo urea levels are valuable for optimizing hemodialysis treatments and tracking the accumulation of toxins for people with end-stage renal failure or recent kidney transplant recipients. 

Various other broths for detecting bacterial and fungal contamination include brain heart infusion broth, tryptose phosphate broth and trypticase soy broth. These should be made up as per manufacturers (Oxoid Ltd. or Difco Labs. see Appendix 3) instructions, but some procedures are given in Appendix 4. 

Frolova, G.M., Kuznetsova, T.A., Michailov VV, and Eliakov, G.B. 2000. Immunoenzyme method for detecting bacterial producers of palytoxin (in Russian). Bioorganicheskaya Khimiya 26(4) 315-320. 

The use of monosaccharide-based arrays to detect bacterial toxins, viruses and bacteria has been reported [219]. Arrays of IV-acetyl galactosamine and IV-acetylneuraminic acid derivatives were immobilized and were probed with fluorescently labeled bacterial cells and protein... 

Table 1.8.1 Regimen for detecting bacterial or fungal contamination in cell cultures...

Table 8 summarizes PCR applications in detecting bacterial pathogens. Most of these studies concern simple detection of the organism rather than diagnosis and await standardized procedures, simplified sample preparation methods, and colorimetric detection formats before they will be practical for clinical laboratories. 

Frozen human tissues represent an ideal situation because these samples allow the insulation and the culture of the pathogen and its immunological and molecular characterization, but this situation is obviously exceptional. The man discovered in the ice in the Tyrol gave rise to research [19] that made it possible to show that his muscles were rich in bacterial DNA. Nevertheless, taking into account the number of detected bacterial species and their variety (Sphingomonas, Afipia, Curtobacterium, Microbacterium, Agromyces, and others), the question of external contaminations can be mentioned. 

States than are predicted by the most extreme estimates to die from cancer secondary to pesticide residue contamination. These are serious problems that have always plagued mankind because it is extremely difficult to detect bacterial contamination during meat processing. However, biotechnology has developed some rapid screening tests to improve the detection of contaminated food before it reaches the consumer. This is another spin-off that has minimal risk and almost immediate benefits. 

Other LAL methods are available based on turbidimetry and colorimetry. Reaction mixtures become turbid as gels, or clots form between LAL and bacterial endotoxin. Turbidimetry (sensitive to 0.(X)1 EU/mL) is more sensitive for detecting bacterial endotoxin than gel clot assays (sensitive to 0.03 EU/mL) because turbidity is discernible at low concentrations of endotoxin at which finn gels do not form. The rate at which turbidity increases is proportional to the concentration of endotoxin in the material under test. This principle may be applied in end-point or kinetic assays. 

The results obtained in the chemical analysis of spoiled peas suggest that the determination of creatinin and ammonia, especially the former, may serve to detect bacterial decomposition in thiB canned food product. ... 

Figure 10.8. Lipid used by Ma and Cheng to detect bacterial toxins.

Neutralization reaction An immunological test used to detect bacterial toxins and antibodies to viruses. 

Major Applications Display device, optical sensors, combustion gas detection system, inks, correction fluid,diapers,n toothpaste, identifying fresh and stale rice, food storage,i" determine glucose in dialysis solution, monitor metabolic activity of microorganisms, detect bacterial infection, psychoactive drugs, dental impression materially Safety/Toxicity No data available... 

Major Appiications Fuel cell power generation system, liquid crystal displays, solor cells, sensors, thermochromic materials,coloring wood,n detergents, assessment of tobacco smoke, cosmetics,14 detect bacterial infections,i multidrug resistance inhibitors, treatment of bums, endodontic, diabetes, obesity, 5 cancer,2o age-related macular degeneration, viral diseases Safety/Toxicity Acute toxicity, combustion toxicity, 4 cytotoxicity, genotoxicity, mutagenicity, nephrotoxicity, phototoxicity, soil toxicity ... 

Major Applications CMOS technology, waveguides, electroluminescent device, inks, plastics, biofuel cells,9 detect bacterial growth, lipids, DNA, diagnosis of diseases related to amyloid accumulation, 3 fluorescent probes,, therapy of viral diseases, photodynamic therapy Safety/Toxicity Carcinogenicity, cytotoxicity, mutagenicity, 9 teratogenicity ... 

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