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1.
Yakugaku Zasshi ; 140(6): 783-788, 2020.
Article in Japanese | MEDLINE | ID: mdl-32475928

ABSTRACT

The latest edition of the Japanese Pharmacopoeia (JP) is the second supplement to the 17th edition containing 324 herbal medicines, of which 176 are crude drugs and 35 are Kampo extracts. Although 148 prescription Kampo extracts are covered by national health insurance, only 35 are listed in the latest JP. However, the sales volume of these 35 Kampo extracts accounts for more than 70% of the total sales volume of Kampo products, as Kampo formulas with higher sales volumes are preferentially listed in the JP. The JP officially defines the origin and description of the listed crude drugs and Kampo extracts and elaborates on their limited values and testing methods. As crude drugs and Kampo extracts are derived from natural products and have the characteristics of traditional medicines, some degree of variation has been experienced during their long-term use, which is one of the crucial differences from chemical drugs. The Japanese Pharmacopoeia Committee on Crude Drugs promotes standardization of the JP by reflecting the actual Japanese market situation. This review explains the characteristics of natural and traditional medicines in crude drug-related items, the JP drafting process and points to be noted, and the significance of listing in the JP.


Subject(s)
Complex Mixtures/standards , Drugs, Chinese Herbal/standards , Pharmacopoeias as Topic/standards , Japan , Medicine, Kampo
2.
Mol Med Rep ; 21(2): 953-958, 2020 02.
Article in English | MEDLINE | ID: mdl-31789410

ABSTRACT

Allergen extracts are commonly utilized for diagnosis and immunotherapy; however, the stability of protease­rich extracts is important for a precise diagnosis and treatment efficacy. The present study determines the optimal conditions for the storage of German cockroach allergen extract. Cockroach extracts were reconstituted in four buffers: normal saline (NS), 50% glycerol in NS, 0.3% phenol in NS, or 0.3% phenol and 50% glycerol in NS. The extracts in different buffers were stored either at room temperature (18­26˚C, RT) or refrigerated (2­8˚C). Subsequently, the protein concentration and allergen content (Bla g 1 and Bla g 2) in the extracts were examined for the course of one year. Extract potency was estimated by inhibition ELISA. At least 90.5% protein, 94.4% Bla g 1, 65.2% Bla g 2, and 91.4% potency remained after one year when 50% glycerol NS was added to the extract with refrigeration. However, less than 13.7% protein, 17.1% Bla g 1, 0% Bla g 2 and 32.5% potency were maintained after one year when 50% glycerol NS was not added to the extract and was maintained at RT. The addition of 0.3% phenol NS did not show significant effects on extract stability. The addition of 50% glycerol NS and refrigerated storage temperature were found to be important factors for increasing the shelf life of protease­rich cockroach extract.


Subject(s)
Allergens/immunology , Cockroaches/immunology , Immunoglobulin E/immunology , Adolescent , Adult , Allergens/chemistry , Allergens/isolation & purification , Animals , Aspartic Acid Endopeptidases/immunology , Cockroaches/chemistry , Cockroaches/enzymology , Cockroaches/metabolism , Complex Mixtures/chemistry , Complex Mixtures/immunology , Complex Mixtures/isolation & purification , Complex Mixtures/standards , Enzyme-Linked Immunosorbent Assay , Female , Glycerol/chemistry , Humans , Male , Middle Aged , Protein Stability , Time Factors , Young Adult
3.
Environ Int ; 120: 535-543, 2018 11.
Article in English | MEDLINE | ID: mdl-30170308

ABSTRACT

Fundamental to regulatory guidelines is to identify chemicals that are implicated with adverse human health effects and inform public health risk assessors about "acceptable ranges" of such environmental exposures (e.g., from consumer products and pesticides). The process is made more difficult when accounting for complex human exposures to multiple environmental chemicals. Herein we propose a new class of nonlinear statistical models for human data that incorporate and evaluate regulatory guideline values into analyses of health effects of exposure to chemical mixtures using so-called 'desirability functions' (DFs). The DFs are incorporated into nonlinear regression models to allow for the simultaneous estimation of points of departure for risk assessment of combinations of individual substances that are parts of chemical mixtures detected in humans. These are, in contrast to published so-called biomonitoring equivalent (BE) values and human biomonitoring (HBM) values that link regulatory guideline values from in vivo studies of single chemicals to internal concentrations monitored in humans. We illustrate the strategy through the analysis of prenatal concentrations of mixtures of 11 chemicals with suspected endocrine disrupting properties and two health effects: birth weight and language delay at 2.5 years. The strategy allows for the creation of a Mixture Desirability Function i.e., MDF, which is a uni-dimensional construct of the set of single chemical DFs; thus, it focuses the resulting inference to a single dimension for a more powerful one degree-of-freedom test of significance. Based on the application of this new method we conclude that the guideline values need to be lower than those for single chemicals when the chemicals are observed in combination to achieve a similar level of protection as was aimed for the individual chemicals. The proposed modeling may thus suggest data-driven uncertainty factors for single chemical risk assessment that takes environmental mixtures into account.


Subject(s)
Complex Mixtures/analysis , Endocrine Disruptors/analysis , Environmental Exposure/analysis , Hazardous Substances/analysis , Models, Statistical , Birth Weight , Child, Preschool , Complex Mixtures/standards , Endocrine Disruptors/standards , Environmental Exposure/standards , Environmental Monitoring/methods , Female , Government Regulation , Hazardous Substances/standards , Humans , Infant, Newborn , Language Development Disorders/epidemiology , Male , Maternal-Fetal Exchange , Pregnancy , Risk Assessment , Uncertainty
4.
Nutrition ; 49: 41-47, 2018 05.
Article in English | MEDLINE | ID: mdl-29571608

ABSTRACT

OBJECTIVE: Because there are almost no standard all-in-one parenteral nutrition admixtures available for infants and children, the aim was to develop standard two-compartment parenteral nutrition bags for different weight categories based on the ESPGHAN/ESPEN (European Society of Paediatric Gastroenterology, Hepatology and Nutrition/European Society for Clinical Nutrition and Metabolism) guidelines. The 1 g/kg/d lipid version for the 3 to 10 kg weight category (PED1) was assessed for short- and long-term physicochemical stability with the ability to add additional electrolytes (PED1+E). METHODS: The lipid compartment A and the all-in-one admixture of A + B + vitamins + trace elements were assessed physically by visual inspection, Sudan red test, pH measurement, and lipid droplet size distribution. Chemical stability for compartment A was evaluated by quantitative analyses of non-esterified fatty acids and peroxide content. The glucose-amino acid-electrolyte compartment B was evaluated physically by visual inspection, measuring particle contamination and pH. Chemical stability was assessed by discoloration, quantitative analyses of glucose, and the amino acids L-cysteine, L-tyrosine, and L-tryptophan. RESULTS: No phase separation or coalescence occurred, and the mean droplet size diameter did not exceed 0.5 µm. Peroxide content and non-esterified fatty acids concentration of compartment A remained well below the limit of acceptation. No precipitation was detected for compartment B; only a slight yellow discoloration was noted at 80 d. Concentrations of glucose, L-tyrosine, and L-tryptophan remained stable; only L-cysteine decreased significantly from its initial concentration. CONCLUSION: The two-compartment PED1 and PED1+E admixtures are stable up to 80 d 2° to 8°C + 24 h room temperature (RT) with an additional 7 d 2° to 8°C + 48 h RT after mixing and addition of vitamins and trace elements.


Subject(s)
Complex Mixtures/chemistry , Complex Mixtures/standards , Parenteral Nutrition Solutions/chemistry , Parenteral Nutrition Solutions/standards , Parenteral Nutrition/standards , Amino Acids/analysis , Chemical Phenomena , Child, Preschool , Electrolytes/analysis , Fatty Acids, Nonesterified/analysis , Female , Glucose/analysis , Humans , Hydrogen-Ion Concentration , Infant , Infant, Newborn , Male , Peroxides/analysis , Practice Guidelines as Topic
5.
Clin Exp Allergy ; 47(5): 604-617, 2017 May.
Article in English | MEDLINE | ID: mdl-28370618

ABSTRACT

In the United States, the Center for Biologics Evaluation and Research of the US Food and Drug Administration regulates biologics used for diagnosis and treatment of allergic diseases. The Code of Federal Regulations 21CFR680.3(e) states that when measured, the potency of an allergenic extract is assessed according to its allergenic activity. As of 2016, 19 allergenic extracts are standardized for potency in the United States. While these standardized extracts constitute a minority of those available, they treat the most prevalent allergies (e.g. grass and ragweed pollens, dust mites, and cat) and those that induce life-threatening anaphylaxis (e.g. Hymenoptera venom). Standardization for potency enhances safety and efficacy of immunotherapy by minimizing the risks of variations in allergen dosing when switching from one lot of manufactured extract to another, and by providing an objective measure of stability of each lot of allergenic extract over time. Allergenic extracts that have multiple immunodominant allergenic proteins are standardized with little or no information about compositional differences among extracts. Here, we propose application of mass spectrometry towards measurement of compositional differences among extracts that may affect the efficacy and safety of allergen immunotherapy. In addition, we discuss of house dust mite allergen extracts as a prototypical complex extract that may be standardized by mass spectrometry.


Subject(s)
Allergens/analysis , Complex Mixtures/analysis , Complex Mixtures/standards , Mass Spectrometry/methods , Mass Spectrometry/standards , Pyroglyphidae/chemistry , Animals , Humans
6.
Talanta ; 150: 525-30, 2016 Apr 01.
Article in English | MEDLINE | ID: mdl-26838439

ABSTRACT

Lichens are symbiotic organisms known for producing unique secondary metabolites with attractive cosmetic and pharmacological properties. In this paper, we investigated three standard methods of preparation of Pseudevernia furfuracea (blender grinding, ball milling, pestle and mortar). The materials obtained were characterized by electronic microscopy, nitrogen adsorption and compared from the point of view of extraction. Their microscopic structure is related to extraction efficiency. In addition, it is shown using thalline reactions and mass spectrometry mapping (TOF-SIMS) that these metabolites are not evenly distributed throughout the organism. Particularly, atranorin (a secondary metabolite of interest) is mainly present in the cortex of P. furfuracea. Finally, using microwave assisted extraction (MAE) we obtained evidence that an appropriate preparation can increase the extraction efficiency of atranorin by a factor of five.


Subject(s)
Complex Mixtures/standards , Hydroxybenzoates/analysis , Hydroxybenzoates/isolation & purification , Lichens/chemistry , Specimen Handling/methods , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods
7.
Sci Total Environ ; 543(Pt A): 757-764, 2016 Feb 01.
Article in English | MEDLINE | ID: mdl-26573369

ABSTRACT

Current chemicals regulation operates almost exclusively on a chemical-by-chemical basis, however there is concern that this approach may not be sufficiently protective if two or more chemicals have the same toxic effect. Humans are indisputably exposed to more than one chemical at a time, for example to the multiple chemicals found in food, air and drinking water, and in household and consumer products, and in cosmetics. Assessment of cumulative risk to human health and/or the environment from multiple chemicals and routes can be done in a mixture risk assessment (MRA). Whilst there is a broad consensus on the basic science of mixture toxicology, the path to regulatory implementation of MRA within chemical risk assessment is less clear. In this discussion piece we pose an open question: should the scope of human MRA cross legislative remits or 'silos'? We define silos as, for instance, legislation that defines risk assessment practice for a subset of chemicals, usually on the basis of substance/product, media or process orientation. Currently any form of legal mandate for human MRA in the EU is limited to only a few pieces of legislation. We describe two lines of evidence, illustrated with selected examples, that are particularly pertinent to this question: 1) evidence that mixture effects have been shown for chemicals regulated in different silos and 2) evidence that humans are co-exposed to chemicals from different silos. We substantiate the position that, because there is no reason why chemicals allocated to specific regulatory silos would have non-overlapping risk profiles, then there is also no reason to expect that MRA limited only to chemicals within one silo can fully capture the risk that may be present to human consumers. Finally, we discuss possible options for implementation of MRA and we hope to prompt wider discussion of this issue.


Subject(s)
Environmental Exposure/legislation & jurisprudence , Environmental Policy , Environmental Pollutants/toxicity , Environmental Pollution/legislation & jurisprudence , Complex Mixtures/standards , Complex Mixtures/toxicity , Environmental Exposure/statistics & numerical data , Environmental Pollutants/standards , Environmental Pollution/statistics & numerical data , European Union , Humans , Risk Assessment
8.
BMC Complement Altern Med ; 15(1): 430, 2015 Dec 04.
Article in English | MEDLINE | ID: mdl-26637485

ABSTRACT

BACKGROUND: Weight-loss medicines, including crude drugs and herbal supplements disguised as diet-aid products, are readily obtainable and distributed widely, especially in Southeast Asia. Even if such products are unapproved or prescription-only medicines, consumers can purchase them through an agency or directly on the Internet. We evaluated the quality and safety of herbal products purchased on the Internet to reveal their influence on public health. METHODS: Diet-aid products containing Bukuryo (Poria sclerotium), Bakumondo (Ophiopogonis tuber), or Daio (rhubarb rhizome) were purchased through websites that did not provide physical addresses or which advertised misleading medicines (e.g., unapproved Cialis 100 mg tablets, Viagra 100 mg tablets) on websites. We carefully noted details in the descriptions on package inserts or accompanying product characteristics and analyzed the ingredients using qualitative and quantitative methods, namely high-performance liquid chromatography equipped with a photodiode array detector. We requested the respective manufacturers to authenticate their products through a structured questionnaire. RESULTS: We purchased 15 items from 15 Internet sites and imported all 15 items to Japan. One item stated to contain rhubarb rhizome was identified as a prescription medicine; the others were dietary supplements and not medicines. Even though we did not analyze the constituents of all crude drugs, we found some active ingredients in the items. Sibutramine was detected in items confirmed to be supplements, including those containing Poria sclerotium and Ophiopogonis tuber. Each capsule contained ≈ 12 mg of sibutramine, which is the daily dose for anti-obesity medicines. Sibutramine is not approved for use in Japan and its sale has been suspended in Europe and the USA owing to serious adverse effects on the circulatory system. CONCLUSIONS: Our findings indicate that dietary supplements containing injurious ingredients are distributed to Japanese consumers and potentially to a broader international audience, and that purchasing them through unreliable websites bears potential health risks. To avoid potential adverse events, there should be adequate alerts about the risks of taking products without appropriate indications.


Subject(s)
Anti-Obesity Agents/analysis , Anti-Obesity Agents/standards , Cyclobutanes/analysis , Internet , Plant Preparations/chemistry , Plant Preparations/standards , Complex Mixtures/chemistry , Complex Mixtures/standards , Cross-Sectional Studies , Dietary Supplements/analysis , Dietary Supplements/standards , Europe , Japan , Ophiopogon , Phytotherapy , Poria , Rheum
11.
Bioorg Khim ; 37(2): 165-70, 2011.
Article in Russian | MEDLINE | ID: mdl-21721250

ABSTRACT

In carrying out proteomic researches using mass-spectrometry there often arises a need to compare experimental data with each other (e.g. control of pathology, the labeled to unlabelled samples). If for peptide identification in different experiments one uses only their exact mass measurements and the retention time in the chromatographic column, difficulties with the identification of chromatographic peaks belonging to the same substances in different chromatograms come up (retention time normalization). Due to inevitable discrepancies in chromatographic conditions of experiments (replacement of chromatographic columns, small changes in mobile phase flow rate or solvent concentration) retention times of the same peptides will diverge from experiment to experiment. In this paper we offer a reliable method for selecting peaks from mass-chromatograms corresponding to the same peptides, which can later be used for retention time normalization (either linear or any other monotone function).


Subject(s)
Complex Mixtures/chemistry , Mass Spectrometry , Observer Variation , Peptide Fragments/analysis , Reference Standards , Algorithms , Animals , Complex Mixtures/standards , Humans , Peptide Fragments/standards , Proteomics/methods
12.
Analyst ; 136(3): 550-9, 2011 Feb 07.
Article in English | MEDLINE | ID: mdl-21107464

ABSTRACT

This work is concerned with the research and development of methodology for analysis of complex mixtures such as pharmaceutical or food samples, which contain many analytes. Variously treated samples (swill washed, fried and scorched) of the Rhizoma atractylodis macrocephalae (RAM) traditional Chinese medicine (TCM) as well as the common substitute, Rhizoma atractylodis (RA) TCM were chosen as examples for analysis. A combined data matrix of chromatographic 2-D HPLC-DAD-FLD (two-dimensional high performance liquid chromatography with diode array and fluorescence detectors) fingerprint profiles was constructed with the use of the HPLC-DAD and HPLC-FLD individual data matrices; the purpose was to collect maximum information and to interpret this complex data with the use of various chemometrics methods e.g. the rank-ordering multi-criteria decision making (MCDM) PROMETHEE and GAIA, K-nearest neighbours (KNN), partial least squares (PLS), back propagation-artificial neural networks (BP-ANN) methods. The chemometrics analysis demonstrated that the combined 2-D HPLC-DAD-FLD data matrix does indeed provide more information and facilitates better performing classification/prediction models for the analysis of such complex samples as the RAM and RA ones noted above. It is suggested that this fingerprint approach is suitable for analysis of other complex, multi-analyte substances.


Subject(s)
Chromatography, High Pressure Liquid/methods , Complex Mixtures/analysis , Drugs, Chinese Herbal/analysis , Atractylodes/chemistry , Calibration , Chromatography, High Pressure Liquid/instrumentation , Complex Mixtures/standards , Drugs, Chinese Herbal/standards , Least-Squares Analysis , Models, Theoretical , Neural Networks, Computer , Principal Component Analysis , Rhizome/chemistry , Spectrometry, Fluorescence , Spectrophotometry, Ultraviolet
15.
Ann Allergy Asthma Immunol ; 99(2): 151-60, 2007 Aug.
Article in English | MEDLINE | ID: mdl-17718103

ABSTRACT

BACKGROUND: Limited data are available on the immunochemical compatibilities of standardized and nonstandardized allergen extracts in immunotherapy vaccines. Extract combinations recommended in immunotherapy practice parameters are based primarily on theoretical considerations rather than on actual product compatibilities. OBJECTIVES: To determine the stabilities of standardized grass, short ragweed, dust mite, and cat extracts after mixing with fungal and cockroach extracts at final product concentrations similar to those recommended for maintenance immunotherapy injections. METHODS: Mixtures were prepared using individual products from multiple sources at variable glycerin concentrations and were analyzed after storage for up to 1 year at 2 degrees C to 8 degrees C. Quantitative analyses included radial immunodiffusion assays for cat Fel d 1 and short ragweed Amb a 1 and human IgE enzyme-linked immunosorbent assay inhibitions for meadow fescue grass and dust mite allergens. Immunoblot analyses provided qualitative patterns of IgE binding. RESULTS: Meadow fescue grass allergens were unstable after mixing with fungal or cockroach extracts but were highly compatible with dust mite extracts from numerous commercial sources. Fescue and dust mite allergen recoveries varied considerably when mixed with different mold extracts. The presence of cockroach extracts reduced dust mite allergen potencies but retained moderate levels of cat and short ragweed allergen activities. In all cases examined, glycerin provided concentration-dependent improvements in allergen recoveries. CONCLUSIONS: Several allergen extract combinations generally regarded as unstable by current practice parameters seem to possess considerable biochemical compatibilities. Use of these mixtures in immunotherapy vaccines is supported for practitioners seeking to optimize formulations, doses, and treatment regimens for their patients.


Subject(s)
Allergens/analysis , Ambrosia/immunology , Cockroaches , Complex Mixtures/standards , Drug Stability , Fungi , Immunotherapy/standards , Pyroglyphidae/immunology , Allergens/immunology , Animals , Antigens, Plant , Cats , Enzyme-Linked Immunosorbent Assay , Glycerol , Glycoproteins/immunology , Humans , Immunoblotting , Immunodiffusion , Plant Proteins/immunology , Rabbits , Tissue Extracts
16.
Int J Cancer ; 120(6): 1161-8, 2007 Mar 15.
Article in English | MEDLINE | ID: mdl-17187366

ABSTRACT

A complex mixture of polycyclic aromatic hydrocarbons (PAH) extracted from coal tar, the Standard Reference Material (SRM) 1597, was recently shown to decrease the levels of DNA binding of the 2 strong carcinogens benzo[a]pyrene (BP) and dibenzo[a,l]pyrene (DBP) in the human mammary carcinoma-derived cell line MCF-7 (Mahadevan et al., Chem Res Toxicol 2005;18:224-231). The present study was designed to further elucidate the biochemical mechanisms involved in this inhibition process. We examined the effects of SRM 1597 on the metabolic activation of BP and DBP toward DNA-binding derivatives in Chinese hamster cells expressing either human cytochrome P450 (CYP) 1A1 or CYP1B1. SRM 1597 inhibited BP-DNA adduct formation through the entire exposure time in cells expressing human CYP1A1, while it significantly inhibited adduct formation only up to 48 hr when co-treated with DBP. Conversely, human CYP1B1-expressing cells were unable to catalyze PAH-DNA adduct formation on treatment with SRM 1597 alone, and on co-treatment with BP or DBP. The data obtained from biochemical experiments revealed that SRM 1597 competitively inhibited the activity of both human enzymes as analyzed by 7-ethoxyresorufin O-deethylation assays. While the Michaelis-Menten constant (K(M)) was <0.4 microM in the absence of SRM 1597, this value increased up to 1.12 (CYP1A1) or 4.45 microM (CYP1B1) in the presence of 0.1 microg/ml SRM 1597. Hence the inhibitory effects of the complex mixture on human CYP1B1 were much stronger when compared to human CYP1A1. Taken together, the decreases in PAH-DNA adduct formation on co-treatment with SRM 1597 revealed inhibitory effects on the CYP enzymes that convert carcinogenic PAH into DNA-binding metabolites. The implications for the tumorigenicity of complex environmental PAH mixtures are discussed.


Subject(s)
Aryl Hydrocarbon Hydroxylases/antagonists & inhibitors , Carcinogens/antagonists & inhibitors , Coal Tar/chemistry , Cytochrome P-450 CYP1A1/antagonists & inhibitors , Polycyclic Aromatic Hydrocarbons/pharmacology , Aryl Hydrocarbon Hydroxylases/drug effects , Benzo(a)pyrene/antagonists & inhibitors , Benzo(a)pyrene/toxicity , Benzopyrenes/toxicity , Carcinogens/toxicity , Complex Mixtures/isolation & purification , Complex Mixtures/pharmacology , Complex Mixtures/standards , Cytochrome P-450 CYP1A1/drug effects , Cytochrome P-450 CYP1B1 , DNA/drug effects , DNA/metabolism , DNA Adducts/analysis , Humans , Polycyclic Aromatic Hydrocarbons/isolation & purification , Polycyclic Aromatic Hydrocarbons/standards , Tumor Cells, Cultured
17.
Rev Alerg Mex ; 53(4): 144-9, 2006.
Article in Spanish | MEDLINE | ID: mdl-17137190

ABSTRACT

Among the aeroallergens associated to asthma and allergic rhinitis, the fungi are a common cause of diagnostic and therapeutic problems. The wide variety and distribution of fungal species and the complex characterization of their allergenicity, is a complex item. The fungus extracts used to diagnose and treat sensitizations are frequently non effective, and different varieties of extracts are globally distributed. The standardization of commercial fungi extracts results extremely important as diagnostic procedure as well as to decide an efficacious and safe immunotherapy. This paper reviews important methodological steps to the standardization of fungi extracts, and finally the clinical use of these extracts.


Subject(s)
Allergens , Asthma/microbiology , Complex Mixtures/standards , Fungi , Hypersensitivity/microbiology , Immunotherapy , Rhinitis, Allergic, Perennial/microbiology , Rhinitis, Allergic, Seasonal/microbiology , Allergens/therapeutic use , Asthma/diagnosis , Asthma/therapy , Fungi/immunology , Humans , Rhinitis, Allergic, Perennial/diagnosis , Rhinitis, Allergic, Perennial/therapy , Rhinitis, Allergic, Seasonal/diagnosis , Rhinitis, Allergic, Seasonal/therapy
18.
Dev Biol (Basel) ; 122: 145-52, 2005.
Article in English | MEDLINE | ID: mdl-16375259

ABSTRACT

Allergen vaccines are complex extracts of natural products, and are used for the diagnosis and treatment of allergic diseases. In the U.S., 19 allergen extracts have been standardized. For these vaccines, the potency is estimated by the skin test responses of highly allergic individuals, and surrogate in vitro tests are established for lot release and quality control. The surrogate tests differ for different extracts. National reference standards to which manufactured lots are compared are maintained at FDA/CBER. Allergen standardization has facilitated the establishment of data-driven release limits.


Subject(s)
Allergens/analysis , Anti-Allergic Agents/standards , Biological Assay/standards , Complex Mixtures/standards , Vaccines/standards , Anti-Allergic Agents/analysis , Complex Mixtures/analysis , Hypersensitivity/diagnosis , Hypersensitivity/therapy , Reference Standards , Vaccines/analysis
19.
Toxicol Lett ; 149(1-3): 197-207, 2004 Apr 01.
Article in English | MEDLINE | ID: mdl-15093265

ABSTRACT

Natural flavour complexes (NFCs) are chemical mixtures obtained by applying physical separation methods to botanical sources. Many NFCs are derived from foods. In the present paper, a 12-step procedure for the safety evaluation of NFCs, 'the naturals paradigm', is discussed. This procedure, which is not intended to be viewed as a rigid check list, begins with a description of the chemical composition of the commercial product, followed by a review of the data on the history of dietary use. Next, each constituent of an NFC is assigned to one of 33 congeneric groups of structurally related substances and to one of three classes of toxic potential, each with its own exposure threshold of toxicological concern. The group of substances of unknown structure is placed in the class of greatest toxic potential. In subsequent steps, for each congeneric group the procedure determines the per capita intake, considers metabolic pathways and explores the need and availability of toxicological data. Additional toxicological and analytical data may be required for a comprehensive safety evaluation. The procedure concludes with an evaluation of the NFC in its entirety, also considering combined exposure to congeneric groups. The first experiences with the use of this procedure are very promising. Future safety evaluations of larger numbers of NFCs will indicate the usefulness of the system, either in its present form or in a form modified on the basis of experience.


Subject(s)
Biological Factors/toxicity , Flavoring Agents/toxicity , Animals , Biological Factors/adverse effects , Biological Factors/chemistry , Biological Factors/standards , Complex Mixtures/adverse effects , Complex Mixtures/chemistry , Complex Mixtures/standards , Complex Mixtures/toxicity , Elettaria/toxicity , Flavoring Agents/adverse effects , Flavoring Agents/chemistry , Flavoring Agents/standards , Humans , Plant Oils/toxicity
20.
Appl Radiat Isot ; 60(2-4): 429-31, 2004.
Article in English | MEDLINE | ID: mdl-14987680

ABSTRACT

The radionuclide 68Ga is mainly a positron emitter (89.2%), with a half-life of 67.7 min. It is used in nuclear medicine, being chemically extracted from the mixture 68(Ge+Ga); its precursor, 68Ge, disintegrates 100% by electron capture, with a half-life of 270.8d (Table of radionuclides, comments and Evaluation). A 4pibeta-gamma coincidence method was used for standardization, with a 4pi proportional beta-detector and a NaI(Tl) gamma detector. Registration of the capture radiations was avoided using foil absorption and a high beta threshold. Using supplementary foils for positron absorption, extrapolation graphs were obtained, with a mean slope of -4.4%. Care was taken to compensate for the loss of 68Ge during the preparation of solid sources for measurement. A combined uncertainty of 1.1% was estimated.


Subject(s)
Algorithms , Gallium Radioisotopes/analysis , Gallium Radioisotopes/standards , Germanium/analysis , Germanium/standards , Reference Standards , Spectrometry, Gamma/methods , Spectrometry, Gamma/standards , Complex Mixtures/analysis , Complex Mixtures/standards , Gamma Rays , Half-Life , Radioisotopes/analysis , Radioisotopes/standards , Reproducibility of Results , Sensitivity and Specificity
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