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1.
Pediatrics ; 57(5): 754-9, 1976 May.
Artículo en Inglés | MEDLINE | ID: mdl-940715

RESUMEN

During part of a national study to formulate criteria for chart audit of quality assurance of child health care, criteria were developed for diagnosis and management of urinary tract infections. These criteria were validated by pediatricians and family physicians in academic medicine and in practice. They were judged relevant to the medical care process and patient outcome by both. The selected criteria were also recommended by the majority of two large physician groups for use in peer review. An important aspect of the study assessed the frequency of performing and recording indicated procedures or tests. In the first three phases of the study these criteria were said to be performed and recorded by a large majority of physicians. However, in the fourth (community) phase, when charts of 166 primary care physicians were actually audited, documentation was so poor that peer review by chart audit would be impractical at present. Assuming proper documentation of the medical care process, similar criteria could be used for chart audit, clinical research, and educational purposes. Since the diagnostic and management process of initial urinary tract infection is established, development of structured health care forms and education in proper record-keeping are two important challenges for those interested in the evaluation of ambulatory care.


Asunto(s)
Auditoría Médica , Pediatría/normas , Revisión por Pares , Infecciones Urinarias/terapia , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Registros Médicos/normas , Infecciones Urinarias/diagnóstico
2.
Pediatrics ; 55(5): 621-9, 1975 May.
Artículo en Inglés | MEDLINE | ID: mdl-805402

RESUMEN

Cromolyn sodium is a recently introduced drug used in the prophylactic treatment of severe, perennial, bronchial asthma, particularly in the pediatric age group. In a multicenter trial, 276 chronic asthmatic patients of eight pediatric allergists entered a randomized, double-blind, placebo-controlled, crossover study lasting 12 weeks. Test compounds of cromolyn sodium or placebo were inhaled four times a day, and daily scores were kept of symptom severity as well as frequency of use of other medications. Patients had statistically significant lower average daily symptom scores when treated with cromolyn sodium as compared to treatment with placebo. A strong subjective preference for cromolyn sodium was expressed by 60% of those completing the trial, versus 9% for placebo. The patients' need for other symptomatic medications also dropped significantly during the cromolyn treatment period.


Asunto(s)
Asma/tratamiento farmacológico , Cromolin Sódico/uso terapéutico , Adolescente , Niño , Preescolar , Ensayos Clínicos como Asunto , Cromolin Sódico/administración & dosificación , Cromolin Sódico/efectos adversos , Femenino , Humanos , Masculino , Placebos , Estadística como Asunto
3.
Bone Marrow Transplant ; 10(2): 171-5, 1992 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1525606

RESUMEN

Pharmacokinetics of high dose thiotepa was studied in 10 children who received this drug as a 2 h infusion at a dose of 300 mg/m2 daily for 3 days. The thiotepa was quantitated using a modification of a previously published gas chromatographic method. Samples were obtained at predetermined times post infusion. The peak plasma concentrations immediately following the infusion ranged from 5.5 to 25.2 (2.0 +/- 6.6) mg/l and the 8 h post infusion ranged from 0.06 to 0.7 (0.32 +/- 0.21) mg/l. The disposition of thiotepa was best described as a simple one compartment open model. The mean (+/- SEM) values for apparent elimination half-life (t1/2 beta), total plasma clearance (CL) and steady volume of distribution (VDss) were 1.3 x h, 11.25 (1.73) l/h/m2 and 19.38 (2.58) l/m2 respectively. In conclusion the pharmacokinetics of high dose thiotepa in children between 2 and 12 years of age do not appear to vary from those reported in children receiving 75 mg/m2 or adults receiving similar doses.


Asunto(s)
Trasplante de Médula Ósea , Neoplasias/cirugía , Tiotepa/farmacocinética , Niño , Preescolar , Femenino , Humanos , Infusiones Intravenosas , Masculino , Neoplasias/sangre , Tiotepa/administración & dosificación , Tiotepa/sangre
4.
Acad Med ; 74(4): 390-2, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10219219

RESUMEN

The Ohio University College of Osteopathic Medicine ranks high among the nation's 19 osteopathic medical schools with respect to the percentage of underrepresented minorities (URMs) in the entering class. The college has strong recruitment and retention programs for URM and disadvantaged students. URM enrollment rose steadily from 11% in 1982-83 to 22% in 1997-98, despite the school's location in a rural, residential public university with few minorities as students or town residents. The college has six programs to support minority students through both undergraduate and medical school: the Summer Scholars Program (1983 to present), an intensive six-week summer program to prepare rising under-graduate seniors and recent graduates to apply to medical school; Academic Enrichment (1987 to present), to support first- and second-year medical students; the Prematriculation Program (1988 to present), an intensive six-week summer program for students who will matriculate in the college; Program ExCEL (1993 to present), a four-year program for undergraduates at Ohio University; the Summer Enrichment Program (1993 to present), an optional six-week program for students who will enter the premedical course at Ohio University; and the Post-baccalaureate Program (1993 to present), a year-long, individually tailored program for URM students who have applied to the medical college but have been rejected. The medical college first focused on supporting students already in the medical school curriculum, then expanded logically back through the undergraduate premedical programs, always targeting learning strategies and survival strategies, peer and faculty support, and mastery of the basic science content. The college plans to create an on-site MCAT preparation program and perhaps expand into secondary education.


Asunto(s)
Educación Premédica , Grupos Minoritarios/educación , Medicina Osteopática/educación , Curriculum , Humanos , Ohio , Facultades de Medicina
5.
Talanta ; 30(4): 251-60, 1983 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18963353

RESUMEN

Tripelennamine hydrochloride, thenyldiamine hydrochloride, and chlorothen citrate have been used as antihistamines and for the treatment of asthma and bronchitis. Toxicological evaluation of these drugs was scheduled as part of a structure-activity relationship study of antihistamines in rats and mice, because of the paucity of such information. Prerequisite for the evaluation was the development of analytical chemical procedures to certify the concentration, homogeneity, and stability of the drugs in dosed feed, to monitor the urine of laboratory personnel to signal their possible exposure to the drugs, and to monitor the wastewater to ensure that the test agents were not discharged into the environment. A high-pressure liquid chromatographic procedure with fluorescence detection was developed for determination of the three antihistamines in admixture in animal feed, human urine, and wastewater at levels of 500, 10 and 10 ng g , respectively. Data on the partition values and use of a silica gel column to aid in the clean-up of sample extracts from the three substrates are reported for the three test agents. Extraction efficiencies and data concerning the stability of tripelennamine hydrochloride and thenyldiamine hydrochloride in animal feed are presented. Description of a new route for synthesis of chlorothen citrate and ancillary data concerning the gas chromatographic analysis for the three drugs in admixture in animal feed at levels as low as 10 mug g are also reported.

6.
Sci Total Environ ; 24(2): 159-75, 1982 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7112098

RESUMEN

In toxicological research with hazardous substances (e.g. carcinogens), wastewater effluent from the test facility must be free of such substances before discharge into the environment. An industrial wastewater processing employing adsorbers of carbon and XAD-2 resin is described; however, chemical assays of each batch of treated effluent must certify the absence of all test agents. Elution profiles and adsorption isotherm tests with the test agents vs. the two adsorbents provided the basis for a "marker" technique which should eliminate the necessity to assay for all test agents in each batch of processed effluent. A radionale is presented for periodic introduction of a "marker" (gentian violet) into the primary adsorbers. If detected in the effluent, the "marker", which elutes from the adsorbers before most of the test agents would signal impending depletion of the adsorbent which could then be replaced. Recommendations to modify the industrial wastewater treatment plant and to implement the "marker" technique are presented as cost-effective alternatives to extensive and laborious chemical assays.


Asunto(s)
Carcinógenos/análisis , Residuos Industriales/análisis , Aguas del Alcantarillado/análisis , Eliminación de Residuos Líquidos/análisis , Cromatografía por Intercambio Iónico/métodos , Control de Calidad
7.
Adv Exp Med Biol ; 392: 93-103, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8850608

RESUMEN

A method is presented for determining the purity of the mycotoxin fumonisin B1 (FB1) by high performance liquid chromatography (HPLC) with evaporative light scattering detection (ELSD). The ELSD is a universal HPLC detector that exhibits a non-linear relationship between analyte amount and the resulting response. A log-log plot of ELSD response with the mass of FB1 injected was used as a calibration curve for determining the quantities of both FB1 and also individual impurities present in samples. Assumptions related to the uniformity of ELSD response for different but related compounds and other issues implied in this use of ELSD data were examined. One potential error produced by use of this method for purity analysis comes from the ELSD's decreased sensitivity for low-concentration analytes. Because analytes become more dilute the longer they remain on a chromatographic column, this sensitivity discrimination can be related to the retention times at which they appear. The ELSD response for FB1 at retention time 15.5 minutes was used to construct a general purpose calibration curve. Whenever a peak appeared at any time other than 15.5 minutes, the discrimination effect was corrected using a an empirically determined weighting factor and a proportion calculated from the retention time difference compared to 15.5 minutes. Purities for two fumonisin samples were calculated using both the ELSD method described above and an electrospray/mass spectrometric method. The quantitative assumptions underlying each method were discussed in order to understand and reconcile differences between the two sets of purity values obtained.


Asunto(s)
Carcinógenos Ambientales/análisis , Cromatografía Líquida de Alta Presión/métodos , Fumonisinas , Micotoxinas/análisis , Luz , Micotoxinas/aislamiento & purificación , Dispersión de Radiación
8.
J Anal Toxicol ; 8(1): 46-50, 1984.
Artículo en Inglés | MEDLINE | ID: mdl-6708478

RESUMEN

Bendectin contains doxylamine succinate and is used for the treatment of nausea and vomiting in pregnant women. Trace level analytical chemical procedures for analysis of doxylamine in primate urine and plasma were required before toxicological tests with the drug in three species of nonhuman primates could be performed. A gas chromatographic procedure using a nitrogen phosphorus detector was developed to quantitate doxylamine in primate plasma at levels as low as 100 ppb. A high-pressure liquid chromatographic procedure was also developed to assay the drug in primate urine at levels as low as 250 ppb. Data from stability studies with the drug in plasma at -5 degrees and -20 degrees C, and recovery of the drug from Bendectin tablets, plasma, and urine are also presented.


Asunto(s)
Cromatografía de Gases/métodos , Cromatografía Líquida de Alta Presión/métodos , Doxilamina/análisis , Piridinas/análisis , Animales , Macaca mulatta
9.
J Anal Toxicol ; 15(6): 289-92, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1779657

RESUMEN

Thermospray mass spectrometry (TSMS) was used to identify the derivatives formed when iodine is reacted with aflatoxins B1 and G1 at approximately 70 degrees C to enhance fluorescence. It was found that stable derivatives were formed by addition of an iodine atom and a methoxy group across the double bond located on the furan ring of the aflatoxin B1 and G1 molecules. TSMS and TSMS/MS daughter spectra of the reaction products of aflatoxin B1 and G1 with iodine provide evidence of the addition of each moiety to produce the iodo-methoxy derivative. The addition of an iodine atom to one carbon and a methoxy group to the other carbon of the furan ring provided molecular weights of 470 and 486 for the products of aflatoxin B1 and G1, respectively.


Asunto(s)
Aflatoxina B1/análisis , Aflatoxinas/análisis , Yodo/química , Aflatoxina B1/análogos & derivados , Aflatoxina B1/química , Aflatoxinas/química , Espectrometría de Masas
10.
J Anal Toxicol ; 9(4): 167-71, 1985.
Artículo en Inglés | MEDLINE | ID: mdl-4033073

RESUMEN

Triethylenetetramine dihydrochloride (TETA) has been used for the treatment of Wilson's disease which is a metabolic disorder that prevents its victims from eliminating excess copper. TETA was scheduled for toxicological evaluation because of a deficiency of such information. Analytical chemical procedures to determine the purity of the drug as well as the proper concentration and stability of the drug in dosed water were prerequisites for the toxicological tests. A high performance liquid chromatography (HPLC) procedure employing ion-pairing and conductivity detection has been developed for the analysis of TETA in dosed water at levels as low as 10 micrograms/mL and for the determination of drug purity. The conductivity detector response was linear over the concentration range of 10 to 100 micrograms/mL. Data are presented concerning the stability of the drug in water during ambient storage and after autoclaving. An ancillary colorimetric procedure for the analysis of aqueous TETA solutions is also presented which is based on measuring the absorbance of the colored TETA copper chelate at 599 nm. The HPLC procedure is applicable to the analysis of TETA and the chemically similar polyamines spermidine and spermine in admixture.


Asunto(s)
Etilenodiaminas/análisis , Trientina/análisis , Animales , Fenómenos Químicos , Química , Cromatografía Líquida de Alta Presión/métodos , Colorimetría , Conductividad Eléctrica , Espectroscopía de Resonancia Magnética , Ratones , Ratas , Espermidina/análisis , Espermina/análisis , Factores de Tiempo , Agua
11.
J Anal Toxicol ; 6(6): 290-3, 1982.
Artículo en Inglés | MEDLINE | ID: mdl-7162138

RESUMEN

Trimellitic anhydride has widespread usage in a variety of industrial processes. Inhalation of the airborne dust and fumes generated by these processes is the primary route of occupational exposure leading to a variety of respiratory maladies. Because of its extensive industrial usage and limited toxicological data, trimellitic anhydride was scheduled for toxicological evaluation. Analytical purity certification and chemical characterization of the chemical were required as prerequisites for such toxicological tests. Therefore, a sensitive and specific procedure for the analysis of trimellitic anhydride and its trimellitic acid impurity in admixture was developed. After methylation with diazomethane, the compounds were assayed by gas chromatography using flame ionization detection. Chromatography on 5% SP-2100 yielded two well separated peaks, which were used for quantitation of the parent compounds. Confirmational identity of trimellitic anhydride was determined by direct insertion probe mass spectrometry, while that of the anhydride methyl derivative and trimellitic acid trimethyl derivative was determined by gas chromatography-mass spectrometry.


Asunto(s)
Ácidos Ftálicos/análisis , Anhídridos Ftálicos/análisis , Ácidos Tricarboxílicos/análisis , Diazometano , Ionización de Llama , Cromatografía de Gases y Espectrometría de Masas
12.
J Anal Toxicol ; 10(4): 142-6, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3747453

RESUMEN

The ammonia chemical ionization mass spectrometric analysis of pyrilamine, the N-oxide of pyrilamine, and related compounds is described. The use of ammonia as the reagent gas produced excellent [M + H]+ ions for these compounds. The suitability of this method for the analysis of two rat urinary metabolites of pyrilamine is demonstrated.


Asunto(s)
Aminopiridinas/metabolismo , Pirilamina/metabolismo , Amoníaco , Animales , Biotransformación , Fenómenos Químicos , Química , Espectrometría de Masas , Ratas , Ratas Endogámicas F344
13.
J Anal Toxicol ; 11(6): 252-6, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-3431093

RESUMEN

Male and female Fisher 344 rats (12 per group) were dosed by gavage with either 2 or 10 mg (based on the free amine) pyrilamine maleate containing about 12 and 6 muCi 14C-pyrilamine maleate, respectively, to determine excretion of the activity as a function of dose and sex with time. Urine and feces were collected at timed intervals through 144 h. Most of the dose (about 70%) was eliminated within 48 h through the urine and feces, but only about 80% of the total dose was recovered during the experiment. Less than 1% of the total dose remained in the rats at the end of the test period. In an additional experiment to determine the location of the remainder of the dose (about 20%), male rats were dosed with 2 mg pyrilamine maleate containing 14C-pyrilamine maleate. After 144 h, exhaustive washing of the cages resulted in recovery of approximately 20% of the dose, thus identifying its location. There were no significant sex or dose related differences observed in the total amount of 14C that was eliminated through the urine or feces and recovered. Urine and feces are the major routes of elimination of pyrilamine maleate in the Fischer 344 rat. The urinary route of elimination was more predominant than the fecal route in both sexes at either dose.


Asunto(s)
Aminopiridinas/metabolismo , Pirilamina/metabolismo , Animales , Cromatografía de Gases , Cromatografía Líquida de Alta Presión , Cromatografía en Capa Delgada , Heces/análisis , Femenino , Masculino , Pirilamina/orina , Ratas , Ratas Endogámicas F344
14.
J Anal Toxicol ; 10(1): 18-23, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3951203

RESUMEN

Experiments were conducted with male and female rats (12 per group) dosed by gavage with 2 or 20 mg (based on the free amine) doxylamine succinate containing about 10 microCi 14C-doxylamine succinate to determine distribution and excretion of the activity as a function of dose and sex with time. Urine and feces were collected at intervals up to 72 hr. Most of the dose (approximately equal to 70%) was eliminated in the first 24 hr after dosing and 95 to 100% of the dose was recovered during the 72-hr course of the experiments with both sexes and dose levels. Less than 1% of the total dose remained in the rats at the end of the test period. The urinary route of elimination was more predominant than the fecal route in both sexes given the 20-mg dose. The fecal route predominates in low-dose males whereas there is no significant difference between urinary and fecal routes of elimination in low-dose females. Preliminary characterization of urinary metabolite form using extraction techniques shows 99% of the metabolites to be in the polar conjugated form.


Asunto(s)
Doxilamina/metabolismo , Piridinas/metabolismo , Animales , Cromatografía Líquida de Alta Presión , Cromatografía en Capa Delgada , Doxilamina/análogos & derivados , Doxilamina/orina , Heces/análisis , Femenino , Masculino , Ratas , Ratas Endogámicas F344 , Distribución Tisular
15.
J Anal Toxicol ; 10(3): 87-92, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-2873269

RESUMEN

The time-course of the metabolic fate of [14C]doxylamine was determined after the p.o. administration of 13 mg/kg doxylamine succinate as Bendectin plus [14C]doxylamine succinate to the rhesus monkey. Urine and plasma samples were analyzed by reversed-phase high performance liquid chromatography (HPLC), chemical derivatization, and mass spectrometry. The cumulative 48-hr urinary metabolic profile contained 81% of the administered radiolabeled dose and consisted of at least six radiolabeled peaks. They were peak 1: unknown polar metabolites (8% of dose); peak 2: 2-[1-phenyl-1-(2-pyridinyl)ethoxy] acetic acid, 1-[1-phenyl-1(2-pyridinyl)ethoxy] methanol, and another minor metabolite(s) (31%); peak 3: doxylamine-N-oxide (1%); peak 4a: N,N-didesmethyldoxylamine (17%); peak 4b: doxylamine (4%); and peak 5: N-desmethyldoxylamine (20%). The plasma metabolic profile was the same as the urinary profile except for the absence of doxylamine-N-oxide. The maximum plasma concentrations and elapsed time to attain these concentrations were as follows. Peak 1: 540 ng/mL, 4 hr; peak 2: 1700 ng/mL, 1 hr; peak 4a: 430 ng/mL, 4 hr; peak 4b: 930 ng/mL, 2 hr; and peak 5: 790 ng/mL, 2 hr. These data suggest that in the monkey, doxylamine metabolism follows at least four pathways: a minor pathway to the N-oxide; a minor pathway to unknown polar metabolites; a major pathway to mono- and didesmethyldoxylamine via successive N-demethylation; and a major pathway to side-chain cleavage products (peak 2) via direct side-chain oxidation and/or deamination.


Asunto(s)
Doxilamina/metabolismo , Antagonistas de los Receptores Histamínicos H1/metabolismo , Piridinas/metabolismo , Animales , Radioisótopos de Carbono , Cromatografía Líquida de Alta Presión , Remoción de Radical Alquila , Desaminación , Doxilamina/análogos & derivados , Femenino , Macaca mulatta , Espectrometría de Masas
16.
J Anal Toxicol ; 7(1): 55-60, 1983.
Artículo en Inglés | MEDLINE | ID: mdl-6834800

RESUMEN

Metabolism experiments were conducted with rats dosed with nine azo dyes based on dimethyl-, dimethoxy-, or dichlorobenzidine to determine whether the free amine congeners, their monoacetyl or diacetyl metabolites, or alkaline hydrolyzable conjugates were excreted in the urine. After preliminary tests of the dyes, 2-mg doses were administered to each animal and urine samples were collected at intervals up to 96 hours. EC/GC procedures were based on the analysis of heptafluorobutyryl derivatives of the free amine congener moieties or their monoacetyl metabolites. Peak levels of metabolites were excreted either 0-12 or 12-24 hours after administration and, in seven of nine instances, no metabolites persisted in the urine after 48 hours. Minimum detectable levels of all metabolites were 12 ppb or less. All nine dyes were shown to be converted to measurable levels of their benzidine-congener-based metabolites in rats.


Asunto(s)
Aminas/orina , Compuestos Azo/metabolismo , Carcinógenos/orina , Colorantes/metabolismo , Animales , Cromatografía de Gases , Masculino , Ratas , Ratas Endogámicas F344
17.
J Anal Toxicol ; 11(3): 113-21, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-3599917

RESUMEN

Elimination and metabolic profiles of doxylamine and its nonconjugated metabolites were determined after the oral administration of [14C]-doxylamine succinate (13.3 mg/kg and 133 mg/kg doses) to male and female Fischer 344 rats. Total urine and fecal recovery of the administered dose was greater than 90% regardless of sex or dose. The cumulative urinary and fecal elimination of these nonconjugated doxylamine metabolites at the 13.3 mg dose was 44.4 +/- 4.4% and 36.0 +/- 5.8% of the total recovered dose for male and female rats, respectively. The cumulative urinary and fecal elimination of the doxylamine nonconjugated metabolites at the 133 mg/kg dose was 38.7 +/- 2.7% and 41.4 +/- 1.0% of the total recovered dose for male and female rats, respectively. In order to determine the contribution of mammalian and bacterial enzymes in the overall metabolism and excretion patterns for doxylamine, two in vitro techniques were investigated. Incubation of [14C]-doxylamine succinate with human and rat intestinal microflora indicated that anaerobic bacteria were not capable of effecting the degradation of [14C]-doxylamine succinate. However, the incubation of [14C]-doxylamine succinate with isolated rat hepatocytes generated several metabolites similar to those observed in vivo. The nonconjugated doxylamine metabolites isolated and identified include: doxylamine N-oxide, desmethyldoxylamine, didesmethyldoxylamine and ring-hydroxylated products of doxylamine and desmethyldoxylamine. The studies demonstrate the role of hepatic metabolism in the elimination of doxylamine succinate in the rat.


Asunto(s)
Doxilamina/metabolismo , Piridinas/metabolismo , Animales , Bacterias/metabolismo , Cromatografía de Gases , Cromatografía Líquida de Alta Presión , Relación Dosis-Respuesta a Droga , Doxilamina/análogos & derivados , Heces/análisis , Femenino , Técnicas In Vitro , Mucosa Intestinal/metabolismo , Hígado/metabolismo , Espectroscopía de Resonancia Magnética , Masculino , Espectrometría de Masas , Ratas , Ratas Endogámicas F344
18.
J Anal Toxicol ; 14(4): 247-51, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-1975634

RESUMEN

Elimination and metabolic profiles of the glucuronide products of doxylamine and its N-demethylated metabolites were determined after the oral administration of (14C)-doxylamine succinate (13.3 and 133 mg/kg doses) to male and female Fischer 344 rats. The cumulative urinary and fecal eliminations of these conjugated doxylamine metabolites at the 13.3 mg/kg dose were 44.4 +/- 4.2% and 47.3 +/- 8.1% of the total recovered dose for male and female rats, respectively. The cumulative urinary and fecal eliminations of conjugated doxylamine metabolites at the 133 mg/kg dose were 55.2 +/- 2.6% and 47.9 +/- 2.5% of the total recovered dose for male and female rats, respectively. The conjugated doxylamine metabolites that were isolated, quantitated, and identified are doxylamine O-glucuronide, N-desmethyl-doxylamine O-glucuronide, and N,N-didesmethyldoxylamine O-glucuronide.


Asunto(s)
Doxilamina/metabolismo , Heces/análisis , Antagonistas de los Receptores Histamínicos H1/metabolismo , Piridinas/metabolismo , Administración Oral , Animales , Cromatografía Líquida de Alta Presión , Doxilamina/administración & dosificación , Doxilamina/análogos & derivados , Doxilamina/orina , Femenino , Antagonistas de los Receptores Histamínicos H1/administración & dosificación , Antagonistas de los Receptores Histamínicos H1/orina , Masculino , Espectrometría de Masas/métodos , Estructura Molecular , Ratas , Ratas Endogámicas F344 , Factores Sexuales
19.
J AOAC Int ; 81(6): 1233-9, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9850585

RESUMEN

A 3-laboratory method trial was conducted to evaluate 2 sample digestion procedures and instrumental determination parameters for analysis of calcium and lead in Ca supplements. Calcium supplements were treated by dry-ash digestion or microwave dissolution prior to spectrometric analysis. In each case, Pb was determined by graphite furnace atomic absorption spectrometry and Ca by inductively coupled plasma-atomic emission spectrometry. Blind duplicates of 6 Ca supplement samples were analyzed after each sample treatment procedure. Matrix pairs contained dissimilar Pb levels to cover the analyte range encountered during method development. Calcium content of the Ca supplement samples also reflected the range seen during method development. Stock solutions of Ca and Pb were supplied to collaborators for preparation of quantitation standards to remove a variable external to the method. National Institute of Standards and Technology Standard Reference Material (NIST SRM) 1486, bone meal, was included to assess method accuracy and recovery at NIST certificate Ca and Pb levels for this material (26.58 +/- 0.24% Ca and 1.335 +/- 0.014 micrograms Pb/g). Analyses of the NIST SRM yielded 25.9 +/- 1.1 and 27.2 +/- 2.3% Ca and 1.53 +/- 0.19 and 1.26 +/- 0.19 micrograms Pb/g for dry-ash and microwave procedures, respectively. Statistical analyses of data indicated acceptable repeatability and reproducibility for determination of Pb and Ca in various Ca supplements. With either sample preparation technique, the method is appropriate for determining Pb or Ca in Ca supplements.


Asunto(s)
Calcio/análisis , Suplementos Dietéticos/análisis , Plomo/análisis , Microondas , Espectrofotometría Atómica , Análisis Espectral/métodos , Productos Biológicos , Contaminación de Medicamentos , Estudios de Evaluación como Asunto , Minerales , Estándares de Referencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
20.
J AOAC Int ; 77(5): 1299-304, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7950430

RESUMEN

A method was developed to analyze various calcium supplements for Ca and Pb content. The analysis involves a dry ash of the supplements followed by wet digestion. The Pb is determined by graphite furnace atomic absorption spectrophotometry (GFAAS). Analysis of Ca is by inductively coupled plasma-atomic emission spectrometry (ICP-AES). Ca supplements fortified with Pb at levels ranging from 0.25 to 10.0 micrograms/g yielded recoveries ranging from 82.7 +/- 4.2 to 105.0 +/- 1.7%. To test accuracy, the method was applied to National Institute of Standards and Technology standard reference materials (NIST SRMs) 1572 citrus leaves and 1486 bone meal. GFAAS analysis of SRM 1572 averaged 13.1 +/- 0.6 micrograms Pb per g (certificate value, 13.3 +/- 2.4 micrograms Pb per g), and analysis of SRM 1486 averaged 1.34 +/- 0.11 micrograms Pb per g (certificate value, 1.335 +/- 0.014 micrograms Pb per g). ICP-AES analysis of SRM 1572 averaged 3.12 +/- 0.01% Ca (certificate value, 3.15 +/- 0.10% Ca by weight), and analysis of SRM 1486 averaged 27.63 +/- 0.27% Ca (certificate value, 26.58 +/- 0.24% Ca). The method's limit of quantitation (LOQ), on supplement Ca basis and a 1 g sample, averaged 0.75 micrograms Pb per 1 g Ca for supplements containing 9 to 35% Ca by weight. At a Pb level of 0.663 micrograms/g Ca, the reproducibility relative standard deviation (RSDr) averaged 7.3% and the repeatability relative standard deviation (RSDR) averaged 8.0%. It is recommended that the method be studied collaboratively.


Asunto(s)
Calcio/análisis , Contaminación de Medicamentos , Plomo/análisis , Espectrofotometría Atómica/métodos , Sensibilidad y Especificidad , Espectrofotometría Atómica/estadística & datos numéricos
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