Sterilization, definition

There is an apparent anomaly in that it also states that the preferred combination of temperature and time is a minimum of 121 °C maintained for 15 minutes, which, by definition, equates to an Fq value of 15. The latter, however, is applicable where the material to be sterilized may contain relatively large numbers of thermophilic bacterial spores, and an Fq of 8 is appropriate for a microbiologically validated process where the bioburden is low and the spores likely to be present are those of (the generally more heat sensitive) mesophilic species. 

Definition of a toxicity with culture of the primerely trepsinised chicken fibroblasts (TCF) included the following stages - incubation of chicken embryo within 11 day - tripsinisation and cultivation of a TCF cells monolayer - 2 days - contact of the tested preparation with the TCF cells monolayer an and the count of a toxicity by the citopathogenic action (CPA)-1-5 day. Hence, definition of a toxicity on cell culture borrowed 14-18 days and at the last two stages demanded strict sterility. 

At the environmental objects toxicity definition with offered method will allow during short time to estimate the toxicity degree of of various objects after eco-disasters or acts of terrorism, with use of the toxic agents. Besides, suggested method does not demand a sterility and allows to use materials from the objects of the external environment, which are not sterile. 

Maintaining cleanliness and sterility is involved in everyday practice but, for the most part, is not under the direct control of anaesthetists. Nevertheless, a familiarity will be expected with the main definitions and methods of achieving adequate cleanliness. 

Hydrocarbon-degrading microorganisms are ubiquitous in most ecosystems [32,117] however, it is often very difficult to prove that transformation, degradation, and mineralization actually occur in the environment because it is difficult to distinguish contributions from biotic and abiotic processes under uncontrolled conditions in the natural environment [338]. In contrast, laboratory assays can provide definitive evidence for microbial degradation, and sterilized samples can be used to determine abiotic losses. Thus, contributions from microbial degradation can be differentiated from abiotic loss by a mass balance... 

Dry heat is used to sterihze and depyrogenate components and drug products. The definition of dry heat sterilization is 170 °C for at least 2 hours and a depyrogenation cycle at 250 °C for more than 30 minutes. Typical equipment includes tunnel sterilizers (force convection, infrared, fiame) and microwave sterilizers. An important aspect is the need to ensure air supply is filtered through HEPA filters. Biological indicators such as Bacillus subtilis can be used to gauge the performance of sterilization. 

When we say force is the cause of motion we talk metaphysics, and this definition, if we were content with it, would he absolutely sterile. For a definition to be of any use, it must teach us to measure force. Moreover that suffices it is not at all necessary that it teach what force is in itself nor whether it is the cause or the effect of motion. 

It should be noted that aseptic assembly of a sterile product becomes difficult with large volume containers and the Food and Drug Administration, for example, would be unlikely to approve an aseptic process for container volumes in excess of 100 mL, i.e., by definition only small volume injectables are acceptable for aseptic assembly. 

Requests for re-collection of samples are, by definition, made a significant time after the original collections so, at the present time, re-collections have been requested only from the first 3 years of collections. To date, a total of 55 re-collections has been made of 48 species by MBG and 47 re-collections of an as yet to be determined number of species by Cl (the determination of the exact number of ethnobotanically selected species is hampered by the sterile status of some of them). Most of these re-collections were from collections made in the first 2 years of the project and it is anticipated that re-collection requests will continue for 1 to 2 years after the sample collecting ends. An expedition in early December 1997 has completed an additional 11 re-collections that were requested early in year 5 of the project. 

Steam sterilization is the method mostly used to sterilize freeze-dryers. High-quality, ultra-pure steam (water for injection standard USP XXII or PhEur equivalent) is used to achieve a minimum exposure of 121 °C for 30 min or the equivalent temperature-time combination for effective sterilization (Table 2.4.1). This method is easy to validate and is recommended by regulatory authorities as being reliable. The definition of sterilization is a validated process used to render a product surface free of all forms of viable micro-organisms (EN 556-1 2001). According to the authorities, a product or surface is only sterile when a validated sterilization process has been applied (EN 550, EN 552, EN 554, EN ISO 14160 and EN ISO 14937). 

Since adult cestodes, freshly removed from a host gut, are invariably covered with a mucus film containing micro-organisms such as yeasts, bacteria and fungi, most workers have used larval stages, which invariably occur in sterile habitats, as initial culture material. Nevertheless, by application of antiobiotics certain species of adult cestodes (e.g. H. diminuta, E. granulosus) may readily be cultured in vitro after removal from the definitive host before the end of the pre-patent period and then maintained in vitro, when egg release is safely contained within the culture vessel (736,811, 867). 

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