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At least 163 records · Page 9Linked to original sources
PubMed2001

[Hydrocortisone Sodium Phosphate Reference Standard (Control 001) of National Institute of Health Sciences].

The raw material of hydrocortisone sodium phosphate was examined for the preparation of the "Hydrocortisone Sodium Phosphate Reference Standard (Control 001)". The analytical data obtained were: pH, 8.3: optical rotation, [alpha]D20 = +126.2 degrees; UV spectrum, lambda max of 248 nm and specific absorbance in water at 248 nm = 338.6; IR spectrum, same as that of the Hydrocortisone Sodium Phosphate Reference Standard (Control 891); free phosphoric acid, 0.2%; free hydrocortisone, 0.01%; thin-layer chromatography, no impurity was detected until 200 micrograms; high-performance liquid chromatography, total amount of impurities estimated to be less than 0.2%; residual solvent, 0.0% (acetone) and 0.02% (ethanol); loss on drying, 1.5%. Based on the above results, the raw material was authorized as the Hydrocortisone Sodium Phosphate Reference Standard (Control 001) of the National Institute of Health Sciences.

Chromatography, High Pressure Liquid↗
PubMed1994

[The Progesterone Reference Standard (Control 931) of the National Institute of Health Sciences].

Raw progesterone material was tested for preparation of the "Progesterone Reference Standard (Control 931)". Analytical data obtained were as follows: melting point, 131.6 degrees C; infrared spectrum, the same as that of the JP Progesterone Reference Standard; optical rotation, [alpha]D20 = +181.1 degrees; thin-layer chromatography, no impurity was detected; high-performance liquid chromatography (HPLC), trace amounts of two impurities were detected; loss on drying, 0.23%; assay results, 99.4% by UV spectrophotometry in the JP XII and 100.5% by HPLC. Based on the above findings, the raw material was authorized as the JP Progesterone Reference Standard (Control 931).

Chemical Phenomena↗
PubMed1994

[The Dexamethasone Reference Standard (Control 931) of the National Institute of Health Sciences].

Raw dexamethasone material was tested for preparation of the "Dexamethasone Reference Standard (Control 931)". Analytical data obtained were as follows: melting point, 245.1 degrees C (decomposition); infrared spectrum, the same as that of the JP Dexamethasone Reference Standard; optical rotation, -alpha-20D = + 76.75 degrees; thin-layer chromatography, two impurities were detected; high-performance liquid chromatography (HPLC), one impurity was detected; loss on drying, 0.14%; assay result, 99.4% by HPLC. Based on the above findings, the raw material was authorized as the JP Dexamethasone Reference Standard (Control 931).

Chemical Phenomena↗
PubMed1992

Diagnosis of pneumonia in adults in general practice. Relative importance of typical symptoms and abnormal chest signs evaluated against a radiographic reference standard.

The diagnostic value of typical symptoms and abnormal chest signs for pneumonia have been evaluated against a radiographic reference standard in 402 adult patients with respiratory tract infection in general practice. Pneumonia was diagnosed in 20 patients by a positive chest radiograph. The doctors diagnosed pneumonia in seven of these on the basis of history and physical examination alone, and in addition in 22 patients with normal radiographs. The diagnostic value of the typical symptoms cough, chest pain, and dyspnoea, reported by the patients on a questionnaire, increased with increasing intensity of the symptoms, and both "very annoying lateral chest pain" and "very annoying dyspnoea" had likelihood ratios (LR) between 4 and 5. The LR of crackles was 3.7. When evaluated against the doctor's clinical diagnosis of pneumonia as reference standard, crackles achieved an LR of 14.8, while the typical symptoms achieved lower LRs than when evaluated against the radiographic reference standard. These discrepancies, which were confirmed by logistic regression, indicate that crackles and other abnormal chest findings are interpreted too frequently as features of pneumonia and that the importance of typical symptoms is underestimated in the diagnosis of pneumonia.

Adult↗
PubMed2005

Characterization of a human reference standard for antibody to Plasmodium falciparum merozoite surface protein 1(42).

Volunteers vaccinated with a candidate malaria vaccine containing merozoite surface protein 1(42) (MSP-1(42)) exhibit antibodies to MSP-1(42) that are measured by enzyme-linked immunosorbent assay (ELISA). The purpose of this study was to make a human reference standard for MSP-1(42) antibody measured in absolute quantity units using pooled plasma samples known to contain high titers of MSP-1(42) antibody based on previous ELISA results. Immobilized metal affinity chromatography was used to determine the amount of MSP-1(42) antibody in this plasma pool. Hexahistidine-tagged MSP-1(42) antigen adsorbed to nickel-chelating resin was used to capture MSP-1(42) antibody from the plasma pool. The intact MSP-1(42) antibody-antigen complexes were eluted and total IgG was measured by an ELISA standardized against purified human IgG. In this way, the human reference standard was determined to contain 48.3 microg/mL of MSP-1(42) antibody. This reference standard may be useful as a quantitative working standard for measuring MSP-1(42) antibody response in future vaccine clinical trials involving MSP-1.

Animals↗
PubMedDate not supplied

Certification of nutrients in Standard Reference Material 1846: infant formula.

In 1996, the National Institute of Standards and Technology (NIST) released Standard Reference Material 1846 (Infant Formula), which can be used as a control material for assigning values to in-house control materials and for validating analytical methods for measurement of proximates, vitamins, and minerals in infant formula and similar matrixes. The SRM was manufactured by preparing a spray-dried formula base containing fat, protein, carbohydrates, and minerals and then combining that formula base with a dry-blend vitamin premix that supplied the vitamins. The Certificate of Analysis for SRM 1846 provides assigned values for concentrations of proximates (fat, protein, etc.), vitamins, and minerals for which product labeling is required by the Infant Formula Act of 1980 and by the Nutrition Labeling and Education Act of 1990. These assigned values were based on agreement of measurements by NIST and/or collaborating laboratories. Certified values are provided for vitamins A (trans), E, C, B2, and B6 and niacin. Noncertified values are provided for solids, ash, fat, nitrogen, protein, carbohydrate, calories, vitamin D, delta-tocopherol, gamma-tocopherol, vitamin B1, vitamin B12, folic acid, pantothenic acid, biotin, choline, inositol, calcium, phosphorus, magnesium, iron, zinc, copper, sodium, potassium, and chloride. Information values are provided for iodine, manganese, selenium, and vitamin K.

Food Analysis↗
PubMed1993

Comparison of oral cholecystography and ultrasonography for evaluating chronic cholecystitis using patient outcome as the reference standard.

RATIONALE AND OBJECTIVES: The authors compared oral cholecystography (OCG) with ultrasound (US) in the detection of chronic gallbladder disease using clinical outcome, rather than pathology results, as the reference standard. METHODS: The authors interviewed 269 patients who underwent either OCG, US, or both, for evaluation of chronic right upper quadrant abdominal pain. The authors considered patients who underwent cholecystectomy with improved symptoms 1 to 4 years after surgery to be reference-standard positive for gallbladder disease, and patients with objective evidence of an alternative diagnosis (eg, peptic ulcer disease), which improved with therapy as reference-standard negative. RESULTS: The sensitivity and specificity of OCG were 83% and 97%, respectively, and for US, 86% and 90%, respectively. CONCLUSIONS: OCG is comparable with US in evaluating of chronic gallbladder disease. In institutions where OCG is used for diagnosing chronic cholecystitis, it may be reasonable to continue using OCG.

Algorithms↗
PubMed1994

[The Ascorbic Acid Reference Standard (Control 931) of the National Institute of Health Sciences].

Raw ascorbic acid material was tested for preparation of the "Ascorbic Acid Reference Standard (Control 931)". Analytical data obtained were as follows: infrared spectrum, the same as that of the JP Ascorbic Acid Reference Standard; optical rotation -alpha-20D, + 21.4 degrees; melting point, 190.3 degrees C (decomposition); loss on drying, 0.02%; assay result, 100.1% by iodometry. Based on the above findings, the raw material was authorized as the JP Ascorbic Acid Reference Standard (Control 931).

Ascorbic Acid↗
PubMed1993

[Ergocalciferol Reference Standard (Control 921) of National Institute of Health Sciences].

The raw material for ergocalciferol was tested for preparation of the "Ergocalciferol Reference Standard (Control 921)". Analytical data obtained were as follows: melting point, 118.1 degrees C; UV and infrared spectra, the same as those for the JP Ergocalciferol Reference Standard; specific absorbance, E1%1 cm = 457.5 (265 nm); thin-layer chromatography and high-performance liquid chromatography (HPLC), no impurities were detected; assay, 101.0% by HPLC. Based on the above results, the raw material was authorized as the Japanese Pharmacopoeia Reference Standard (Control 921).

Chromatography, High Pressure Liquid↗
PubMed1993

[Cholecalciferol Reference Standard (Control 921) of National Institute of Health Sciences].

The raw material for cholecalciferol was tested for preparation of the "Cholecalciferol Reference Standard (Control 921)". Analytical data obtained were as follows: melting point, 89.9 degrees C; UV and infrared spectra, the same as those for JP Cholecalciferol Reference Standard (Control 901), respectively; specific absorbance at 265 nm E1%1 cm = 472.2; optical rotation, [alpha]20D = 107.1 degrees; thin-layer chromatography and high-performance liquid chromatography (HPLC), no impurities were detected; assay, 99.97% by HPLC. Based on the above results, the raw material was authorized as the Japanese Pharmacopoeia Reference Standard (Control 921).

Cholecalciferol↗
PubMed1994

[The Cyclandelate Reference Standard (Control 931) of the National Institute of Health Sciences].

Raw cyclandelate material was tested for preparation of the "Cyclandelate Reference Standard (Control 931)". Analytical data obtained were as follows: melting point, 57.4 degrees C; ultraviolet spectrum, lambdamax = 252.0, 258.1 and 264.1 nm and E 1cm 1% = 5.85 (252.0 nm), 6.95 (258.1 nm), 5.30 (264.1 nm), respectively; infrared spectrum, the same as that of the JP Cyclandelate Reference Standard; thin-layer chromatography, no impurities were detected up to 1000 micro g; high-performance liquid chromatography (HPLC), no impurities were detected; loss on drying, 0.03%; assay result, 101.4% by HPLC. Based on the above findings, the raw material was authorized as the JP Cyclandelate Reference Standard (Control 931).

Chemical Phenomena↗
PubMed1989

[Lysozyme Reference Standard (Control 871) of the National Institute of Hygienic Sciences].

A candidate for the Lysozyme Reference Standard (Control 871) of the National Institute of Hygienic Sciences was prepared. Purity of the standard material examined electrophoretically was more than 99.5%. Lysozyme potency of the standard material was assayed turbidimetrically using dry-cells of Micrococcus luteus as a substrate and compared with that of the Lysozyme Reference Standard (Control 865). Potency of the standard material was in satisfactory agreement with that of the standard and was defined as 1 mg [potency] per mg.

Amino Acids↗
PubMed1994

[Elcatonin Reference Standard (Control 921) of National Institute of Health Sciences].

The raw material of elcatonin was examined for preparation of the "Elcatonin Reference Standard". The candidate material was evaluated by a domestic collaborative study in which five laboratories participated. The biological activity was determined to be 11.3 Unit/Amp. against the International Elcatonin Reference Standard (Code 84/614), based on one hour hypocalcaemia rat bioassay. In spite of the differences in rat strain, sex, administration method, dosage and assay method for serum calcium etc., the separately obtained biological activities for the candidate agreed closely with each other (95% confidence limits 11.08-11.53 Unit/Amp.). The physico-chemical evaluation of the candidate material was also performed, by using HPLC and amino acid chromatography. Based on the above results, this raw material was authorized to be the Elcatonin Reference Standard of the National Institute of Health Sciences.

Amino Acids↗
PubMed1995

[Ergocalciferol reference standard (Control 941) of the National Institute of Health Sciences].

The raw material for ergocalciferol was tested for preparation of the "Ergocalciferol Reference Standard (Control 941)". Analytical data obtained were as follows: melting point, 117.6 degrees C; UV and infrared spectra, the same as those for JP Cholecalciferol Reference Standard; specific absorbance, E1%1cm = 458 (265 nm); thin-layer chromatography and high-performance liquid chromatography (HPLC), no impurities were detected, respectively; assay, 100.6% by HPLC. Based on the above results, the candidate raw material was authorized as the Japanese Pharmacopoeia Reference Standard (Control 941).

Chemical Phenomena↗
PubMed1995

[Cholecalciferol reference standard (Control 941) of the National Institute of Health Sciences].

The raw material for cholecalciferol was tested for preparation of the "Cholecalciferol Reference Standard (Control 941)". Analytical data obtained were as follows: melting point, 88.5 degrees C; UV and infrared spectra, the same as those for JP Cholecalciferol Reference Standard (Control 923), respectively; specific absorbance at 265 nm E1%1cm = 471; optical rotation, [alpha]20D = +107.3 degrees; thin-layer chromatography and high-performance liquid chromatography (HPLC), no impurities were detected, respectively; assay, 101.3% by HPLC. Based on the above results, the candidate raw material was authorized as the Japanese Pharmacopoeia Reference Standard (Control 941).

Chemical Phenomena↗
PubMed1994

[The Thiamine Hydrochloride Reference Standard (Control 931) of the National Institute of Health Sciences].

Raw thiamine hydrochloride material was tested for preparation of the "Thiamine Hydrochloride Reference Standard (Control 931)". Analytical data obtained were as follows: melting point, 242.7 degrees C (decomposition); infrared spectrum, the same as that of the JP Thiamine Hydrochloride Reference Standard; thin-layer chromatography, one impurity was detected; high-performance liquid chromatography (HPLC), a trace amount of one impurity was detected; assay results, 100.4% by UV spectrophotometry and 100.0% by HPLC, respectively. Based on the above findings, the raw material was authorized as the JP Thiamine Hydrochloride Reference Standard (Control 931).

Chemical Phenomena↗
PubMed1993

[Riboflavin Reference Standard (Control 921) of National Institute of Health Sciences].

The raw material for riboflavin was tested for preparation of the "Riboflavin Reference Standard (Control 921)". Analytical data obtained were as follows: melting point, 283.8 degrees C (decomposition); specific absorbance, E1%1 cm = 852 (267 nm), 275 (373 nm), 325 (446 nm); infrared spectrum, the same as that of JP Riboflavin Reference Standard; optical rotation [alpha]20D = 138.5 degrees; thin-layer chromatography, no impurities were detected up to 6 micrograms; high-performance liquid chromatography, a small amount of 9 impurities were detected; loss on drying, 0.16%; assay, 100.3% by spectrophotometry. Based on the above results, the raw material was authorized as the Japanese Pharmacopoeia Reference Standard (Control 921).

Chromatography, High Pressure Liquid↗
PubMed2006

Standard reference materials (SRMs) for measurement of inorganic environmental contaminants.

NIST has developed an extensive collection of environmental SRMs, starting with fuel and biologically related materials in the late 1960s and now encompassing all sectors of environmental research. Advances in analytical methodology, including multi-element isotope-dilution mass spectrometry (IDMS) and expanded instrumental neutron-activation analysis (INAA) capabilities, enable value assignment based on fewer but better-characterized independent analytical techniques. The special advantages of IDMS for determination of S and Hg and for multi-element characterization of small-sample air particulate matter (SRM 2783) by IDMS and INAA are emphasized. Developments in materials production include the issuance of fresh-frozen biological materials and of jet-milled natural-matrix materials with improved homogeneity, including highly homogeneous air particulate matter and sediment SRMs for small-sample analytical techniques.

Animals↗