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PubMedDate not supplied

Development of the NIST bone ash standard reference material for environmental radioactivity measurement.

The bone ash standard reference material (SRM), a blend of 4% contaminated human bone and 96% diluent bovine bone, has been developed for radiochemical method validation and quality control for radio-bone analysis. The massic activities of 90Sr, 226Ra, 230Th, 232Th, 234U, 235U, 238U, 238Pu, (239 + 240)Pu and (243 + 244)Cm were certified using a variety of radiochemical procedures and detection methods. Measurements confirmed undetectable radionuclide heterogeneity down to a sample size of 5 g. thereby implying adequate blending of particulate materials with dilution factors of up to 17,900. The results among most of the intercomparison laboratories and their methods were consistent. Disequilibrium was observed for decay chains: 234U(0.67 mBq/g)-230Th(0.47 mBq/g)-226Ra(15.1 mBq/g)-210Pb(23 mBq/g)-210Po(13 mBq/g) and 232Th(0.99 mBq/g)-228 Ra(6.1 mBq/g)-228Th(7.1 mBq/g). The disequilibria were the results of mixing occupationally contaminated human bone with natural bovine bone and the fractionation during internal biological processes. The massic activity of 210Pb, 228Th and 241Am were not certified because of insufficient 228Ra and 241Pu data and lack of knowledge in how 222Rn and its daughters will be fractionated in the SRM bottle over time.

Animals↗
PubMed1999

Reference standards for determination of DNA content of plant nuclei.

Flow cytometry was used to compare 14 potential reference standards for plant DNA content determination. Both chicken and plant internal standards were used, as were propidium iodide (PI) and 4'-6-diamidino-2-phenylindole (DAPI) as fluorochromes. Means and standard errors of the means are presented for the 14 potential reference standards, and the means are compared to those obtained by Feulgen densitometry. Five species are recommended as an initial set of international standards for future plant DNA content determinations: Sorghum bicolor cv. Pioneer 8695 (2C = 1.74 pg), Pisum sativum cv. Minerva Maple (2C = 9.56 pg), Hordeum vulgare cv. Sultan (2C = 11.12 pg), Vicia faba (2C = 26.66 pg), and Allium cepa cv. Ailsa Craig (2C = 33.55 pg). It is recommended that the reference standard of choice be one with 2C and 4C nuclear DNA content peaks similar to, but not overlapping, the 2C and 4C peaks of the target species. We recommend PI as the fluorochrome of choice for flow cytometric determination of plant DNA content. DAPI should be used only if the estimated DNA value is corroborated by using a second stain that has no bias for AT- or GC-rich sequences within genomes.

Journal Article↗
PubMed2001

[Alprostadil Reference Standard (Control 001) of National Institute of Health Sciences].

The raw material of Alprostadil was examined for the preparation of "Alprostadil Reference Standard (Control 001)". Analytical data obtained were: IR spectrum, same as that of the Alprostadil Reference Standard (Control 923); thin-layer chromatography, no impurities were detected until 20 micrograms; high-performance liquid chromatography (HPLC), total amount of impurities estimated to be less than 0.2%. Based on the above results, the raw material was authorized as the Japanese Pharmacopoeia Alprostadil Reference Standard (Control 001).

Alprostadil↗
PubMed2004

Clinical examination, endosonography, and MR imaging in preoperative assessment of fistula in ano: comparison with outcome-based reference standard.

PURPOSE: To prospectively evaluate the relative accuracy of digital examination, anal endosonography, and magnetic resonance (MR) imaging for preoperative assessment of fistula in ano by comparison to an outcome-derived reference standard. MATERIALS AND METHODS: Ethical committee approval and informed consent were obtained. A total of 104 patients who were suspected of having fistula in ano underwent preoperative digital examination, 10-MHz anal endosonography, and body-coil MR imaging. Fistula classification was determined with each modality, with reviewers blinded to findings of other assessments. For fistula classification, an outcome-derived reference standard was based on a combination of subsequent surgical and MR imaging findings and clinical outcome after surgery. The proportion of patients correctly classified and agreement between the preoperative assessment and reference standard were determined with trend tests and kappa statistics, respectively. RESULTS: There was a significant linear trend (P < .001) in the proportion of fistula tracks (n = 108) correctly classified with each modality, as follows: clinical examination, 66 (61%) patients; endosonography, 87 (81%) patients; MR imaging, 97 (90%) patients. Similar trends were found for the correct anatomic classification of abscesses (P < .001), horseshoe extensions (P = .003), and internal openings (n = 99, P < .001); endosonography was used to correctly identify the internal opening in 90 (91%) patients versus 96 (97%) patients with MR imaging. Agreement between the outcome-derived reference standard and digital examination, endosonography, and MR imaging for classification of the primary track was fair (kappa = 0.38), good (kappa = 0.68), and very good (kappa = 0.84), respectively, and fair (kappa = 0.29), good (kappa = 0.64), and very good (kappa = 0.88), respectively, for classification of abscesses and horseshoe extensions combined. CONCLUSION: Endosonography with a high-frequency transducer is superior to digital examination for the preoperative classification of fistula in ano. While MR imaging remains superior in all respects, endosonography is a viable alternative for identification of the internal opening.

Abscess↗
PubMed1995

Characterization of human lymphoid cell lines GM9947 and GM9948 as intra- and interlaboratory reference standards for DNA typing.

The incorporation of reference DNA is crucial to the validation of any DNA typing protocol. Currently, reference DNA standards are restricted to molecular size DNA ladders and/or tumor cell line DNA. Either of these, however, presents some limitations. We have rigorously characterized two Epstein-Barr virus (EBV)-immortalized human lymphoid cell lines--GM9947 (female) and GM9948 (male)--to determine their suitability as alternative in-line standards for three widely employed allele profiling strategies. Twenty-one highly polymorphic VNTR-based allelic systems (7 RFLPs, 2 AmpFLPs, and 12 STRs) distributed over 12 chromosomes were scrutinized along with 3 gender-based discriminatory systems. The genetic stability of each locus was confirmed over a period of 225 in vitro population doublings. Allele size estimates and degree of informativeness for each of the 21 VNTR systems were compiled. The reproducibility of allele scoring by traditional RFLP analyses, using both cell lines as reference standards, was also verified by an interlaboratory validation study involving 13 analysts from two geographically distinct forensic laboratories. Taken together, our data indicate that GM9947 and GM9948 genomic DNAs could be adopted as reliable reference standards for DNA typing.

Base Sequence↗
PubMed1999

[Digoxin Reference Standard (Control 991) of National Institute of Health Sciences].

The raw material of digoxin was examined to prepare a "Digoxin Reference Standard". The analytical data obtained were: optical rotation, [alpha](20)D = + 11.7 degree; loss on drying, 0.008%, infrared spectrum, the same as that of the Digoxin Reference Standard (Control 807); high-performance liquid chromatography, several impurities detected and the total amount estimated to be about 0.31%, assay by spectrophotometry, 100.1%. Based on the above results, the candidate material was authorized as the Digoxin Reference Standard (Control 991) of the National Institute of Health Sciences.

Digoxin↗
PubMed1996

[The Somatropin Reference Standard (Control 951) of the National Institute of Health Sciences].

Somatropin material was examined for preparation of the "Somatropin Reference Standard". The candidate material was evaluated by a domestic collaborative study in which eight laboratories participated. The protein content was determined to be 4.5 mg/Vial based on amino acid analysis. Because of the possibility of application as a chemical reference standard for assay by the HPLC method, a physico-chemical evaluation of the candidate material was also performed. By SE-HPLC, the content of polymer, dimer were determined to be 0.54%, 0.98%, respectively. By RP-HPLC, the early peak area ascribed to desamido and sulfoxide form was 1.07% of the total peak area. And for informational data, the potency of the candidate material, being estimated by three different biological methods, weight gain assay, tibia test and adiposeconversion assay is 14.8 IU/vial. Based on the above results, the candidate was authorized as the Somatropin Reference Standard of the National Institute of Health Sciences.

Amino Acids↗
PubMed1999

[Fluocinonide Reference Standard (Control 981) of National Institute of Health Sciences].

The raw material of fluocinonide was examined for preparation of the "Fluocinonide Reference Standard (Control 981)". The analytical data obtained were: UV spectrum, lambda max of 237.4 nm; IR spectrum, same as that of the Fluocinonide Reference Standard (Control 841); optical rotation, [alpha]20(D) = + 84.4 degree, thin-layer chromatography, one impurity detected; high-performance liquid chromatography, three impurities detected and total amount estimated to be about 0.20%; loss on drying, 0.15%; assay by HPLC, 99.6% Based on the above results, the raw material was authorized as the Fluocinonide Reference Standard (Control 981) of the National Institute of Health Sciences.

Fluocinonide↗
PubMed2001

[Ergocalciferol Reference Standard (Control 001) of National Institute of Health Sciences].

The raw material of ergocalciferol was examined for the preparation of "Ergocalciferol Reference Standard (Control 001)". Analytical data obtained were: melting point, 114.8 degrees C; UV and infrared spectra, the same as those of JP Ergocalciferol Reference Standard (Control 971); specific absorbance, E1ca1% = 471(265 nm); optical rotation, [alpha]D20 = +102.4 degrees; thin-layer chromatography, no impurities were detected until 100 micrograms; high-performance liquid chromatography (HPLC), total amount of impurities estimated to be less than 0.1%. Based on the above results, the raw material was authorized as the Japanese Pharmacopoeia Ergocalciferol Reference Standard (Control 001).

Chemical Phenomena↗
PubMed2001

[Cholecalciferol Reference Standard (Control 001) of National Institute of Health Sciences].

The raw material of cholecalciferol was examined for the preparation of "Cholecalciferol Reference Standard (Control 001)". Analytical data obtained were: melting point, 83.2 degrees C; UV and infrared spectra, the same as those of JP Cholecalciferol Reference Standard (Control 971), respectively; specific absorbance at 265 nm, E1ca1% = 478; optical rotation, [alpha]D20 = +108.6 degrees; thin-layer chromatography, no impurities were detected until 100 micrograms; high-performance liquid chromatography (HPLC), total amount of impurities estimated to be less than 0.05%. Based on the above results, the raw material was authorized as the Japanese Pharmacopoeia Cholecalciferol Reference Standard (Control 001).

Chemical Phenomena↗
PubMed1998

[Ergocalciferol Reference Standard (Control 971) of National Institute of Health Sciences].

The raw material for ergocalciferol was examined for preparation of the "Ergocalciferol Reference Standard (Control 971)". Analytical data obtained were as follows: melting point, 116.7 degrees C; UV and infrared spectra, the same as those for JP Cholecalciferol Reference Standard; specific absorbance, E1 cm 1% = 461(265 nm); optical rotation, [alpha]D20 = +102.5 degrees; thin-layer chromatography and high-performance liquid chromatography (HPLC), no impurity was detected; assay, 102.4% by HPLC. Based on the above results, the raw material was authorized as the Ergocalciferol Reference Standard (Control 971) of National Institute of Health Sciences.

Chemical Phenomena↗
PubMed2001

The NO release test as a functional reference standard for laser Doppler fluxmetry in cutaneous microangiology.

BACKGROUND/AIMS: The application of one-dimensional laser Doppler fluxmetry (LDF) to clinical research is widespread. Large intra- and interindividual fluctuations in perfusion impede the objective evaluation of studies and hinder a standardised reproducibility. Attempts are made to minimise these biological fluctuations of the measured values by means of functional tests, standardised measuring conditions and large study populations. An intraindividual fixed standard that also facilitates interindividual comparability as a reference parameter would be desirable. METHODS: By applying a nitric oxide (NO) release cream, a maximal vasodilatation is produced in a circumscribed skin area and optically registered by means of LDF. An LDF quotient is defined as a measure of the reproducibility. A total of 123 test subjects with dermatological diseases were measured at intervals of 60 min on the volar underarm on clinically normal skin with and without NO release cream. RESULTS: The LDF quotient of the NO release test represents a stable, readily reproducible individual parameter and is appropriate as a reference standard for resting flux measurements. Therefore, we define an LDF factor that includes the maximal vasodilatation as a specific assessment characteristic and thus allows a more powerful, functionally oriented assessment of the individual measurements. CONCLUSION: The NO release test is appropriate as a reference standard for laser Doppler fluxmetry and realises a high reproducibility of individual measurements.

Humans↗
PubMed1998

[Cholecalciferol Reference Standard (Control 971) of National Institute of Health Sciences].

The raw material for cholecalciferol was examined for preparation of the "Cholecalciferol Reference Standard (Control 971)". Analytical data obtained were as follows: melting point, 83.8 degrees C; UV and infrared spectra, the same as those for JP Cholecalciferol Reference Standard (Control 945), respectively; specific absorbance at 265 nm, E1 cm 1% = 485; optical rotation, [alpha]D20 = +107.4 degrees; thin-layer chromatography and high-performance liquid chromatography (HPLC), no impurity was detected; assay, 98.9% by HPLC. Based on the above results, the raw material was authorized as the Cholecalciferol Reference Standard (Control 971) of National Institute of Health Science.

Chemical Phenomena↗
PubMed1999

[Tocopherol Succinate Reference Standard (Control 981) of National Institute of Health Sciences].

The raw material of tocopherol succinate was tested for preparation of the "Tocopherol Succinate Reference Standard (Control 981)". The analytical data obtained were: infrared spectrum same as that of the Tocopherol Succinate Reference Standard (Control 8510); specific absorbance, E(1%)1 cm (286 nm) = 40.7; thin-layer chromatography, no impurities detected until 50.0 microgram; high-performance liquid chromatography (HPLC),three impurities detected and amount of tocopherol succinate estimated to be 98.2%, loss on drying, 0.19%, assay by HPLC, 101.7%. Based on the above results, the raw material was authorized as the Japanese Pharmacopoeia Reference Standard (Control 981).

Government Agencies↗
PubMed1996

[Digitoxin Reference Standard (Control 951) of the National Institute of Health Sciences].

The raw material of digitoxin was tested for preparation of the "Digitoxin Reference Standard (Control 951)". Analytical data obtained were as follows: loss on drying, 0.0%; infrared spectrum, the same as that of the JP Digitoxin Reference Standard (Control 845); thin-layer chromatography, no impurity was detected; high-performance liquid chromatography (HPLC), two kinds of impurities were detected and the total amount was estimated to be 0.16 +/- 0.01% (n = 3); assay, 99.0% by HPLC. Based on the above results, the raw material was authorized as the JP Digitoxin Reference Standard (Control 951).

Chemical Phenomena↗
PubMed1996

[Betamethasone Reference Standard (Control 951) of the National Institute of Health Sciences].

The raw material of betamethasone was tested for preparation of the "Betamethasone Reference Standard (Control 951)". Analytical data obtained were as follows: loss on drying, 0.0%; infrared spectrum, the same as that of the JP Betamethasone Reference Standard (Control 845); thin-layer chromatography, no impurity was detected; high-performance liquid chromatography (HPLC), two kinds of impurities were detected and the total amount was estimated to be 0.16 +/- 0.01% (n = 3); assay, 100.0% by HPLC. Based on the above results, the raw material was authorized as the JP Betamethasone Reference Standard (Control 951).

Betamethasone↗
PubMed1996

[Cyanocobalamin Reference Standard (Control 951) of the National Institute of Health Sciences].

The raw material of cyanocobalamin was tested for preparation of the "Cyanocobalamin Reference Standard (Control 951)". Analytical data obtained are as follows: loss on drying, 1.8%; infrared spectrum, the same as that of the JP Cyanocobalamin Reference Standard (Control 936); thin-layer chromatography, three impurities were detected; high-performance liquid chromatography (HPLC), eight to nine kinds of impurities were detected and the total amount of impurities was estimated to be 1.6 +/- 0.13% (n = 4); assay, 99.7% by spectrophotometry specified in the JP XII and 100.4% by HPLC, respectively. Based on the above results, the raw material was authorized as the JP Cyanocobalamin Reference Standard (Control 951).

Chemical Phenomena↗
PubMed1990

[Cyanocobalamin Reference Standard (Control 891) of National Institute of Hygienic Sciences].

Cyanocobalamin was tested for preparation on the "Cyanocobalamin Reference Standard (Control 891)". Analytical data obtained were as follows: loss on drying, 9.77%; infrared spectrum, same as that of the Cyanocobalamin Reference Standard (Control 871); thin-layer chromatography, five contaminants were detected; high-performance liquid chromatography, nine contaminants were detected; assay, 100.00% by JP XI method and 99.79% by HPLC method in terms of the JP Reference Standard (Control 871), respectively. On the basis of the above results, this material was authorized as the Japanese Pharmacopoeia Standard (Control 891).

Chromatography, High Pressure Liquid↗