Biological indicator evaluator

Aiiempts have been made to standardize at least the conditions in which D-values may be determined, AAMI [8) have specified a sterilizing vessel, termed a biological indicator evaluator resistometer (BIER vessel), which allows rapid attainment and termination of exposure conditions in a precise and accurate manner. 

Association for the Advancement of Medical Instrumentation (1982). Standard for Biological Indicator Evaluator Resistometer (BIER) Ethylene Oxide Vessels. Arlington, Va. AAMI. 

To critically evaluate and rank candidate biological indicators useful for monitoring trends in merctrry... 

The criteria listed in Section 4.3.1 were applied to the selection of biological indicators to ensure their relevance and utility for assessing trends in the bioaccumulation of MeHg associated with altered loadings of mercmy to aquatic systems. This evaluation, based largely on the discussion in Section 4.3.2, is summarized in Table 4.1. 

Polymeric forms of ACC 71 were synthesized and their biological activities evaluated. Synergistic interactions between ACC polymers and the cytokinin 6-N-benzylaminopurine have been indicated [120]. 

L-Canaline shares with canavanine an appreciable potential for eliciting adverse biological effects. Evaluations with].. minor of some 55 naturally occurring and synthetic amino acids indicated that canavanine and canaline were amongst the most toxic canaline exhibited slightly greater growth-inhibition than canavanine ( ). These toxic non-protein amino acids interact to curtail additively the proliferation of this aquatic plant (24). 

If it is assumed that the radiation sterilizer equipment and facilities have been qualified and microbiological studies have been conducted as previously outlined, the next step in the validation process is the complete evaluation of the radiation sterilization cycle. Tests are conducted to determine the effect of minimum and maximum product density on the ability of the minimum or nominal radiation dose—determined during the microbiological studies to produce a given log reduction in the biological indicator population—to sterilize the load. For example, it was found that a 0.2-Mrad dose of cobalt-60 will produce a 1-log reduction in the population of B. pumilus. The microbial load of a one-package polyvinyl chloride (PVC) device (intravenous administration site) was estimated to be approximately 1000. A probability of a nonsterility level of 10 6 is desired, therefore theoretically, the minimum dose necessary to produce a 9-log reduction in the microbial population is 1.8 Mrad. 

Some structural modifications of racemic calanolide A have been studied by us. Removal of Cn-methyl or methyl groups at both Cn and Cg positions maintains the basic stereochemistry of (it)-calanolide A as well as evaluates their anti-HIV activity. ( )-Cn-demethyl calanolide A and ( )-calanolide A exhibited similar potencies, whereas the 6,6,11-demethyl calanolide A also had diminished activity. The primary biological indicated that two methyl groups in the Cg position might be necessary for antiviral activity. 

Hair has been used in the biomonitoring of various elements, for example, arsenic, thallium, and zinc, and has been used in the monitoring of drugs and biological substances. The level of mercury in hair is widely used as a biological indicator for exposure to methyl mercury (MeHg). In addition, hair samples have been utilized to evaluate environmental exposure to pollutants such as lead, and occupational exposures to metals such as nickel and chromium. However, the ATSDR has stated ... 

Schmidt. P.F. (1984). Localization of trace elements with the laser microprobe mass analyzer (LAMMA), Trace Elements in Medicine, 1,13-20 Sherwood. R.A., Rocks, B.F., and Riley, C. (1984). The use of flow-injection analysis (FIA) with atomic absorption detection for the determination of clinically relevant elements. Paper presented at 2nd BNAAS Symposium, Leeds, July 1984 Triebig, G., and Schaller, K.H. (1984). Copper, in Alessio, L, Berlin, A., Boni, M., Roi, R., Biological indicators for the assessment of human exposure to industrial chemicals, p. 57-62, EUR 8903 EN, Commission of the European Communities Van der Vyner, F.L, Verbreuken, A.H., Van Grieken, R.E., and DeBroe, M.E. (1985) Laser microprobe mass analysis A tool for evaluating histochemical staining of trace elements, Clin. Chem., 31. 351... 

Let us do an actual problem, Example 3.1, the data for which are from an actual D value computation for steam sterilization. Biological indicators (strips of paper containing approximately 1 x 10 bacterial spores per strip) were affixed to stainless steel hip joints. In order to calculate a D value, or the time required to reduce the initial population by 1 logio, the adequacy of the regression model must be evaluated. Because bo and bi are unbiased estimators, even when serial correlation is present, the model y = bo + biX + et may still be useful. However, recall that e, is now composed of e,- i + di, where the 4s are N 0, 1). 

Hazard identification. All suspected conditions that may pose inhalation or skin absorption hazards that are immediately dangerous to life or health (IDLH) or other conditions that may cause death or serious harm shall be identified during the preliminary survey and evaluated during the detailed survey. Examples of such hazards include, but are not limited to, confined space entry, potentially explosive or flammable situations, visible vapor clouds, or areas where biological indicators, such as dead animals or vegetation, are located. 

As with any type of test for biological response evaluation, immunotoxicity tests should be valid and have been shown to provide accurate, reproducible results that are indicative of the effect being studied and are useful in a statistical analysis. This implies that appropriate control groups are also included in the study design. 

Ellis K, Yasumura S, Vartsky D, and Cohn S. (1983). Evaluation of biological indicators of body burden of cadmium in humans. Fundamentals and Applied Toxicology, 3, 169-174. 

The need to carry out extensive surveys of Taxus species for their taxol content and to monitor taxol in clinical studies has spurred efforts to develop new analytical methods for taxol purification. Solvent extraction methods are always inexpensive and easy to handle. Different solvent systems started from very nonpolar solvents (e.g., n-hexane) [6] senupolar system (chloroform and acetone or combination of dichloromethane methanol) [7] and very polar system (methanol or ethanol alone or with H2O) [7] have been employed for extraction of taxoids from bark or leaves of Taxus species. To date only chromatographic methods have been reported. Sadeghi-aliabadi et al. in their studies to find an optimized solvent for taxol extraction indicated that the solvent 100 % acetone is the best solvent to extract higher amount of taxol fi om Taxus baccata needles. They confirmed their results by HPLC, ESI-LCMS, and biological cytotoxic evaluations of extracted compounds [8]. 

Evaluation of Different Biological Indicators of Lead Exposure Related to Neuropsychological Effects in Children... 

The present study was designed to evaluate the relationship between different biological indicators of body lead burden and some neuropsychological functions in 7-8-year-old children, living in an industrial area polluted by lead. The neuropsychological functions were estimated by a battery of 6 psychometric tests. Lead was measured in blood, hair and teeth, and mean levels of 11.45 jug dl 9.94 figg and 6.80 jUg g respectively, were obtained. 

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