Biomedical subjects

D A Raines

Publications and source records attributed to D A Raines.

At least 19 recordsLinked to original sources

PubMed1996

Fetal surveillance: issues and implications.

In the past, the fetus was considered healthy until evidence was presented to the contrary. With the acceptance of fetal surveillance as part of the pregnancy experience, diagnostic testing and data are thought to be necessary to prove the healthiness of the fetus. The availability of fetal surveillance techniques has transformed the pregnancy experience from a developmental process and a miracle of nature to a risk-dominated and technology-guided event. The implications of this trend significantly affect the care of pregnant women and the role of nurses as providers of comprehensive, individualized nursing care.

Female↗

PubMed1996

Choices of neonatal nurses in ambiguous clinical situations.

This article reports a study of the nurse's choice of level of management and factors influencing that choice in three ambiguous clinical situations related to neonatal nursing. A nationwide mail survey, using a Likert scale, was conducted on a random sample of the membership of the National Association of Neonatal Nurses. The findings of this research suggest that nurses have clearly defined choices related to the degree of intensity of management of infants, based on consideration of the information available to the nurse in the neonatal setting. These findings have implications for nursing practice and education and consequences for the quality of nursing care provided to infants and their families.

Adult↗

PubMed1996

Parents' values: a missing link in the neonatal intensive care equation.

Neonatal intensive care has become a widely accepted component of our health care system. Its acceptance and growth are related to increased technology and specialization. However, little consideration has been given to the process of making decisions about the use of neonatal intensive care from the perspective of the patient's family. This article reviews the existing literature related to parents' opinions and perceptions of care in the NICU and proposes a framework for the exploration of the value systems of parents of infants requiring neonatal intensive care.

Attitude to Health↗

PubMed1995

Steady-state kinetics of fluoxetine and amitriptyline in patients treated with a combination of these drugs as compared with those treated with amitriptyline alone.

The steady-state kinetics of amitriptyline (AMI), fluoxetine (FLU), and their active metabolites nortriptyline (NTRIP) and norfluoxetine (NFLU) were studied in 15 patients treated once daily for long durations with 50 mg of AMI and 20 mg of FLU. These compounds were analyzed simultaneously in plasma by liquid chromatography. The means and (SEM) of the steady-state concentrations (Css) of AMI, NTRIP, FLU, and NFLU were 80.6 (14.2), 52.6 (10.3), 85.3 (16.1), and 90 (13.6) ng/mL, respectively, and the apparent oral clearances (CLor) of AMI and FLU were 42.4 (8.6) and 14.9 (2.5) L/hr, respectively. The metabolite/drug steady-state concentration ratio (Css(m)/Css) for NTRIP/AMI was 0.75 (0.14) and for NFLU/FLU was 1.27 (0.17). There was a significant correlation (P < 0.05) between Css of FLU and that of AMI or NTRIP. The Css and Css(m)/Css values obtained for AMI were higher (P < 0.056 and P < 0.0034, respectively) than those we observed in 10 patients treated solely with the same dose of AMI. The twofold increase in Css of AMI and ninefold increase in Css of NTRIP seem to be the result of inhibition of the metabolism of these compounds by FLU, particularly the ring hydroxylation. Norfluoxetine may have a small inhibitory influence on the metabolism of NTRIP but lacks this effect on the metabolism of AMI.

Adolescent↗

PubMed1995

Relationship between antipyrine metabolism and acetylation phenotype in health and chronic liver diseases.

The authors examined the activity of N-acetyltransferase and that of microsomal P-450 isoenzymes in health and hepatic disease state by determining the acetylation phenotype and the total (CLAP) and metabolic clearances of antipyrine to form norantipyrine or N-demethylantipyrine (MCLnora), 3-hydroxymethylantipyrine (MCLhma), and 4-hydroxyantipyrine (MCLha) in 21 healthy subjects and in 33 patients with chronic liver diseases (CLD) and investigated the relationship between the activities of these two enzyme systems. The acetylation phenotype was determined according to the urinary caffeine metabolites test. The mean and (SEM) of CLAP, MCLhma, MCLha, and MCLnora in healthy subjects were 2.42 (0.264), 0.193 (0.031), 0.322 (0.045), and 0.288 (0.04) L/h, and those observed in patients with CLD were 0.98 (0.1), 0.076 (0.015), 0.131 (0.026), 0.103 (0.022) L/h, respectively. The prevalence of fast acetylation among the healthy subjects and patients with CLD was 38% and 39%, respectively. Although all metabolic clearances appear to be reduced in healthy slow acetylators, the reduction was only significant in MCLnora, indicating a direct association between the activity of N-acetyltransferase and that of P-450 IIIA3 responsible for the N-demethylation of antipyrine. Conversely, slow acetylators with CLD exhibited significantly higher CLAP and near-significantly larger metabolic clearances including MCLnora, which suggests that P-450 activity in fast acetylators is more sensitive to chronic liver diseases than in slow acetylators.

Acetylation↗

PubMed1995

Antipyrine clearance and metabolite excretion in patients with chronic hepatitis C.

BACKGROUND/AIMS: Our aim was to study whether chronic hepatitis C affects the three metabolic pathways of the model drug antipyrine differently. METHODS: We measured antipyrine clearance from saliva as well as urinary excretion of its main metabolites 4-hydroxy-antipyrine, 3-hydroxy-methyl-antipyrine, and nor-antipyrine in 24 patients with chronic hepatitis C and in 21 healthy control subjects. Due to incomplete urine collection, 12 liver patients and three controls were excluded. RESULTS: Antipyrine clearance (mean +/- SD) was significantly lower in patients with chronic hepatitis C, 1.2 +/- 0.7 l.h-1 (n = 12), than in controls (n = 18), 2.2 +/- 1.0 l.h-1 (p = 0.006). The urinary excretion of each of the metabolites was depressed to an equal extent in liver patients. The severity of the liver disease, as assessed by Child Pugh score, serum albumin and bilirubin, correlated significantly with antipyrine clearance and urinary excretion of the metabolite 3-hydroxy-methyl-antipyrine. The hepatitis activity index (Knodell) correlated with 3-hydroxy-methyl-antipyrine and 4-hydroxy-antipyrine, only. CONCLUSIONS: Moderate-severe chronic hepatitis C does not seem to depress the three main metabolic pathways of antipyrine differently.

Adult↗

PubMed1994

Values influencing neonatal nurses' perceptions and choices.

The purpose of this research was to identify the values influencing the nurses' perception and choice of behavior in a hypothetical clinical situation. The theoretical framework was Rokeach's theory on the nature of human values and value systems. A descriptive study using a mailed survey was conducted on a random sample of 331 members of the National Association of Neonatal Nurses. Data on individual nurse's values, perception of information, and behavioral choices were collected with an investigator-developed questionnaire consisting of a values scale, and an information scale and choice alternatives related to three hypothetical vignettes: a low-birthweight infant, an infant with chromosomal anomalies, and a chronically ill infant. Results of this study indicate that nurses identified a hierarchy of values related to their practice. Information related to infant characteristics was consistently most important; however, in uncertain situations, rules or external protocols had an increased influence on the behavioral choice process. The behavioral choice option with the greatest agreement was different for each situation. A consistently negative correlation between the options within each vignette indicates that nurses have clearly defined choice preferences. Model testing revealed a consistent relationship across the three vignettes between the variable being just and protocol, doing right and infant characteristics, and infant characteristics and the choice options (p < .05).

Adult↗

PubMed1994

Elimination of antipyrine and its metabolites in interferon treated hepatitis C.

1. To study the effect of interferon on hepatic drug metabolism in chronic hepatitis C, we examined nine patients before and at the end of 6 months of interferon treatment. 2. Routine liver function was determined together with the salivary clearance of antipyrine and the 48 h urinary excretion of the main metabolites of antipyrine: 4-hydroxyantipyrine, 3-hydroxymethylantipyrine and norantipyrine before and after 6 months of interferon treatment. 3. Liver pathology, routine liver function, and antipyrine metabolism remained unchanged after patients were treated for 6 months with interferon for a histologically advanced but clinically compensated chronic hepatitis C.

Administration, Oral↗

PubMed1994

Elimination studies of antipyrine and its metabolites in healthy Saudi Arabians.

1. We measured the antipyrine clearance in 18 healthy Saudi subjects and determined the urinary excretion of three of its metabolites: 4-hydroxyantipyrine (4-OH AP), norantipyrine (NOR AP) and 3 hydroxymethylantipyrine (3-OHM AP) in 21 subjects. 2. The mean +/- SD of the antipyrine clearance was 2.4 +/- 1.1 h-1 (range 1.0-5.5 l h-1) and the corresponding value per kg body weight was 0.6 +/- 0.2 ml min-1 kg-1. Urinary excretion of antipyrine (AP), 4-OH AP, NOR AP and 3-OHM AP expressed as a percentage of the oral dose of antipyrine given was 2.8 +/- 2.2, 14.5 +/- 6.9, 12.3 +/- 5.6 and 7.6 +/- 3.2 respectively. 3. Compared to Africans, Saudis preferentially metabolize AP to NOR AP and compared to Caucasians to 3-OHM AP, rather than to 4-OH AP. These discrepancies may reflect age differences between the study populations rather than genetic or ethnic variations.

Administration, Oral↗

PubMed1993

Concurrent liquid chromatographic measurement of fluoxetine, amitriptyline, imipramine, and their active metabolites norfluoxetine, nortriptyline, and desipramine in plasma.

An expedient and specific liquid chromatographic method for a concurrent measurement of fluoxetine (FLU), norfluoxetine (NFLU), amitriptyline (AMI), nortriptyline (NTRIP), imipramine (IMI), and desipramine (DES) is described. Using a mixture of acetonitrile:methanol:0.056 M ammonium acetate:1 M ammonium hydroxide (100:10:4.5:2.6, by volume) as mobile phase, the compounds along with doxepin (DOX) (internal standard) were separated on a 10 mu, 8 mm x 10 cm C18 Resolve cartridge in conjunction with radial compression liquid chromatographic module, and were detected in the effluent spectrophotometrically at 220 nm. A hexane:isoamyl alcohol (98:2, by volume) solution was used for extraction of plasma and the drugs were removed from the organic phase with 0.03% phosphoric acid prior to injection. Under these conditions, no interference in the assay was observed, and the retention times of NFLU, DOX, FLU, AMI, IMI, NTRIP, and DES were 7.8, 11.6, 16, 17.8, 20.9, 31, and 35 min, respectively. The assay was highly linear (r > 0.994), and the within- and between-day coefficient of variance was consistently < or = 9.8%. This assay is currently being used to simultaneously measure these drugs in patients and to investigate their steady-state pharmacokinetics when used in combination.

Amitriptyline↗

PubMed1993

Effect of diabetic state and related disorders on the urinary excretion of magnesium and zinc in patients.

We examined the urinary excretion of magnesium and zinc in 175 diabetics [19 insulin-dependent (type I) and 156 insulin-independent (type II)] and in 160 control subjects of the same origin by determining the ratio of the concentration of each of these metals to that of creatinine (creat). Electrothermal atomic absorption spectrophotometry was used for analyzing Mg and Zn in urine. There was no significant difference in the urinary excretion of Mg between the control group [mean (SEM) = 362.6 (15.1) mmole of Mg/mole of creat] and the overall [350.2 (15.7) mmole Mg/mole creat], type I [368.4 (45.0) mmole Mg/mole creat], or type II [347.9 (16.7) mmole Mg/mole creat] diabetics regardless of the disorders associated with diabetes (cardiovascular diseases, neuropathy, retinopathy, infections, and hepatic disease). In contrast, diabetics of both types [2.67 (0.14) mmole Zn/mole creat] with or without a diabetes associated disorder excreted significantly (p = 0.031 to 0.0000) more Zn than did the control subjects [1.76 (0.09) mmole Zn/mole creat]. There was positive correlation between hemoglobin A1c and urinary loss of Mg (p = 0.013) or Zn (p = 0.0241) in patients with type II diabetes. From these data, it appears that of the two elements examined only Zn is associated with higher urinary loss in diabetic state. The discrepancy between our results and those of previous studies for Mg may be ascribed to dissimilarities in the diet habits and metabolism of Mg among diabetics of different geographical origins.

Cardiovascular Diseases↗

PubMed1993

Values: a guiding force.

This article discusses the concept of values and the roles of values in the ethical decision-making process. The acquisition of values and the role of different types of values are explored. A model is presented to illustrate the nature of values as a guide to behavior. Finally, the role and impact of the individual values systems of health care professionals and patients are identified as essential ingredients in the resolution of ethical dilemmas.

Adult↗

PubMed1993

Environments that support ethical nursing practice.

Creating an ethical work environment in a health care organization is both necessary and difficult. In the process of providing care, nurses often make decisions with ethical implications. This decision making is enhanced when the work environment supports an ethical approach. Nursing can implement strategies to support ethical decision making.

Decision Making↗

PubMed1993

Ethical reflection and resolution.

Resolution of ethical issues requires critical thinking and problem solving skills. This article reviews the professional code of ethics for nurses and decision-making frameworks as guides to assist nurses in becoming active participants in the process of ethical reflection.

Adult↗

PubMed1992

N-acetylation polymorphism and diabetes mellitus among Saudi Arabians.

The acetylator phenotypes of 200 Saudi diabetics and an equal number of control subjects of the same origin were determined by measuring the peak height ratio of two urinary caffeine metabolites, 5-acetylamino-6-formylamino-3-methyluracil (AFMU) and 1-methylxanthine (1MX), using a simplified high-performance liquid chromatographic method. Urine samples were collected from the diabetics and the control subjects who regularly drink coffee, tea, or caffeinated beverages as part of their normal daily diet. The patients were classified as either type 1 (insulin-dependent) (28 patients) or type 2 (insulin-independent) diabetics (172 patients) according to standard criteria. The reproducibility of acetylator phenotype was established by examining the peak height ratio of AFMU/1MX in 18 diabetics and 6 control subjects on different days. Significant differences in the proportion of rapid acetylators were observed between type 1 (53.6%) and type 2 (33.7%) diabetics (P < or = .0436), and between the control group (26%) and the overall diabetics (36.5%) (P < or = .024) or those with type 1 disease (P < or = .0028). Also, there was a significant (P < or = .0436) association between rapid acetylator status and type 1 diabetes mellitus.

Acetylation↗

PubMed1992

Simultaneous microdetermination of rifampin, deacetylrifampin, isoniazid, and acetylisoniazid in plasma by liquid chromatography with dual electrochemical and spectrophotometric detection.

A rapid liquid chromatographic method for simultaneous determination of isoniazid (INH), acetylisoniazid (AINH), rifampin (RIF), and deacetylrifampin (DARIF) in microsamples of deproteinized plasma is described. The compounds and internal standard (IS) (diphenylcarbazide) were separated on a 10-microns, 8 mm x 10-cm phenyl Radial Pak cartridge in conjunction with a binary linear gradient system at a flow rate of 3 ml/min. A dual electrochemical (+800 mV) and spectrophotometric (334 nm) detection system with a computerized data station was employed to measure the above compounds in the effluent. Prior to injection, the plasma sample was diluted (2:1) with a pH 3, 0.075 M phosphate buffer after adding the internal standard (6.67 micrograms/ml of plasma) and passed through an Amicon Centrifree-MS filter at 2000g. Under these conditions, no interference in the analysis was observed, and the retention times of AINH, INH, IS, DARIF, and RIF were 3.95, 4.89, 15.82, 17.25, and 19.34 min, respectively. The linearity of the assay for all four compounds was excellent (r greater than 0.9925), and the between- and within-day CV was not greater than 8% at any concentration. This method is currently being used for therapeutic monitoring and pharmacokinetic studies of INH, RIF, and their major metabolites in patients with tuberculosis.

Chromatography, Liquid↗

PubMed1991

Simplified determination of antipyrine clearance by liquid chromatography of a microsample of saliva or plasma.

We describe a simplified and rapid liquid chromatographic determination of antipyrine clearance (CLAP) calculated from peak height ratios of drug/internal standard. Saliva or plasma was collected 24 hr after the oral administration of 1 g of antipyrine to the subject. A 25-microliter aliquot of the sample is deproteinized with acetonitrile containing 3-nitrophenol (internal standard) and injected into a radial compression module equipped with a 10-micron, 8 mm x 10-cm C18 cartridge, using a 0.025 M aqueous solution of sodium acetate and acetonitrile (88.5:11.5). The minimum measurable concentration was 0.2 microgram/ml. The obtained CLAP values in five healthy subjects and five patients with chronic liver disease coincided well (r greater than 0.9994) with those generated by the use of an established method. The antipyrine clearance in the healthy subjects ranged from 2.203 to 5.721 liters/hr, while in patients with chronic liver disease it was significantly (P less than 0.0027) less (range, 0.544 to 1.103 liter/hr). We also determined antipyrine clearance in two of these subjects given lower doses of this drug and found that the dose has no significant impact on this parameter.

Antipyrine↗

PubMed1991

Urinary excretion of chromium, copper, and manganese in diabetes mellitus and associated disorders.

The urinary excretion of chromium, copper and manganese was determined in 185 diabetics and in an equal number of control subjects by measuring the concentration of each of these metals using electrothermal atomic spectrophotometry and dividing the values by the urinary concentration of creatinine (creat) in each subject. The mean (SEM) values for the overall diabetics and the control group were 2.32 (0.17) and 2.62 (0.22) mumol Cr/mole of creat, 76.5 (5.5) and 73.9 (6.1) mumol Cu/mole of creat, and 3.56 (0.44) and 2.66 (0.3) mumol Mn/mole of creat, respectively. There was no correlation between the urinary excretion of any of the metals examined and age or sex of either group. While the cardiovascular or ophthalmologic diseases associated with diabetes did not influence the excretion of any of these metals, significantly higher urinary excretion of Cu was exhibited by diabetics with neuropathy (p < 0.0027) or infections (p < 0.014) than by those without. Also, diabetics with liver disorders or those who were not treated with insulin excreted significantly more Mn than did their diabetic counterparts.

C-Peptide↗