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Biomedical subjects

S A Phillips

Publications and source records attributed to S A Phillips.

33 records · Page 2Linked to original sources
PubMed1992

Fluorimetric assay of D-lactate.

A fluorimetric assay for D-lactate in human blood samples was developed using an endpoint enzymatic assay with D-lactate dehydrogenase from Staphylococcus epidermidis. The intrabatch and interbatch coefficients of variance were 8.7% (n = 4) and 16.6% (n = 4), respectively. The limit of detection in blood was 3.73 nmol/ml. The assay suffers minor interference from S-D-lactoylglutathione, which was also present in the blood samples. The concentration of D-lactate in blood was (mean +/- SE, nmol/ml) normal healthy individuals, 11.0 +/- 1.2 (n = 7); and diabetic patients, 20.0 +/- 1.3 (n = 55) (a significant increase in diabetes mellitus; P < 0.01, Mann-Whitney U test).

Calibration↗
PubMed1992

The assay of methylglyoxal in biological systems by derivatization with 1,2-diamino-4,5-dimethoxybenzene.

A procedure for the assay of methylglyoxal in biological systems is described, together with sample storage, sample processing procedures, and statistical evaluation. Specimen data are presented. Methylglyoxal was assayed by derivatization with 1,2-diamino-4,5-dimethoxybenzene and high-performance liquid chromatography (HPLC) of the resulting quinoxaline, 6,7-dimethoxy-2-methylquinoxaline, with spectrophotometric or fluorescence detection. Derivatization, solid-phase extraction, and HPLC were performed under acid conditions to prevent the spontaneous formation of methylglyoxal from glyceraldehyde 3-phosphate and dihydroxyacetone phosphate during the assay. The limits of detection in the biological matrix were 45 pmol (absorbance detection) and 10 pmol (fluorimetric detection), the recovery was 58%, and the intra- and interbatch coefficients of variance were 7.7 and 30.0%, respectively. The concentration of methylglyoxal in whole blood from normal healthy human individuals was (mean +/- SE, nM) 256 +/- 92 (n = 12) and that from diabetic patients was 479 +/- 49 (n = 55), showing a significant increase in diabetes mellitus (P < 0.01; Mann-Whitney U test). Sample processing under acidic conditions was essential to avoid interferences. Previous estimates of the concentration of methylglyoxal in biological samples require re-evaluation.

Calibration↗
PubMed1992

Cocaine: its effects on maternal and child health.

Cocaine abuse has become one of America's leading public health problems. Its use throughout pregnancy is associated with an increased risk of abruptio placentae, stillbirth, and preterm labor. Cocaine-associated neonatal complications include congenital malformations, decreased fetal growth, seizures, cerebral infarction and hemorrhage, auditory system deficits, sudden infant death syndrome, cardiac arrhythmias, necrotizing enterocolitis, and behavioral changes. Children followed throughout the first year of life continue to show developmental delay. Infants and children growing up in cocaine-abusing families are at risk for drug-related injuries. Accidental and intentional intoxication has occurred in infants and children from the smoke of freebase cocaine. The drug has also caused intoxication in breast-feeding infants. Adolescents experimenting with cocaine are at risk, with an apparently high frequency of seizures and loss of consciousness, as well as behavioral changes and psychosocial dysfunction.

Abnormalities, Drug-Induced↗
PubMed1990

Productivity measurement in hospital libraries: a case report.

This paper examines the concept of productivity measurement and its application in a hospital library. Component steps in development of a typical productivity measurement system are described, including a process for calculation of quantitative workload standards. Problems and potential benefits of participating in productivity measurement programs are discussed, and managerial strategies suggested.

Efficiency↗
PubMed1989

Etiology and mortality of status epilepticus in children. A recent update.

We reviewed the medical records of 218 episodes of status epilepticus in 193 children who were admitted to the hospital between 1983 and 1987. Of the episodes, 61% were in boys and 39% in girls, with an age range of 1 month to 14 years (average, 3.2 years). The majority of episodes (73%) occurred in patients who were less than 5 years old, with 61% less than 3 years old and 28% less than 1 year old. Status epilepticus as the initial seizure occurred in 71% of episodes. In patients under 1 year of age, 75% of episodes were associated with acute causes (bacterial meningitis in 28% and electrolyte disorders in 30%), and 23% were idiopathic (19% associated with fever). In children less than 3 years old, 47% of episodes had an acute cause, 9% had a previously known seizure disorder, and 32% were idiopathic (30% associated with fever). In patients older than 3 years, 28% of episodes were associated with acute causes, 38% were known epileptics, and 13% were idiopathic (11% had fever). Overall mortality was 6%, with 1% of all episodes ending in death during the presenting seizure. We conclude that the etiology of status epilepticus is age related, with acute causes being more common in patients with a younger age at presentation. When our data are compared with other large studies in children, it appears that mortality associated with status epilepticus has decreased.

Acute Disease↗
PubMed1987

Rat liver membranes contain a 120 kDa glycoprotein which serves as a substrate for the tyrosine kinases of the receptors for insulin and epidermal growth factor.

The receptors for insulin and epidermal growth factor possess tyrosine-specific protein kinase activity which may play a role in mediating the biological actions of these two peptides. We have identified a 120 kDa glycoprotein (pp120) in rat liver plasma membranes which can be phosphorylated by the insulin receptor in a cell-free system and in intact cultured hepatoma cells. In the present report, we have demonstrated in a cell-free system that solubilized epidermal growth factor receptors can phosphorylate tyrosine residues in pp120.

Animals↗
PubMed1987

Test of cure for gonorrhea in teenagers. Who complies and does continuity of care help?

This study evaluates factors influencing test of cure (TOC) compliance for gonorrhea in teenagers attending a public sexually transmitted disease (STD) clinic. The efficacy of providing continuity of care to improve the TOC rate is also evaluated. Overall, females complied better (54%) than males (33%), and younger males better than older males (greater than 16 years of age). Of patients with a prior history of gonorrhea, the TOC rates were significantly higher for those who had previously kept their TOC appointment. Continuity of care did not improve the TOC rate, but initial contact with a clinician appeared to influence the return rate of female adolescents. Male adolescents will apparently require a different intervention strategy to improve their appointment keeping.

Adolescent↗
PubMedDate not supplied

Novel technique for the combined recovery, extraction and clean-up of forensic organic and inorganic trace explosives samples.

This paper describes a simple processing and analysis scheme for explosives trace swab samples which deals both with organic and inorganic materials. Swabs, wetted with ethanol or ethanol/water mixture, were extracted with ethanol/water mixture. The extract was passed directly through a simple column containing an acrylonitrile/styrene copolymer adsorbent. The adsorbent retained common organic explosives, which were recovered with an efficiency of 30-50% as a relatively clean ethyl acetate solution. The concentrated ethyl acetate eluate was analysed using gas chromatography with chemiluminescence or mass spectrometric detection. The unretained inorganic ions and sugars, which were recovered with generally high efficiency as an ethanol/water solution, could be directly analysed using ion chromatography and/or capillary electrophoresis. Minor difficulties encountered in the analysis of sugars, fluoride and phosphate were examined.

Chromatography, Gas↗
PubMedDate not supplied

Failure of a lottery incentive to increase compliance with return visit for test-of-cure culture for Neisseria gonorrhoeae.

The impact of the financial incentive of playing a lottery on the rate of return for test-of-cure cultures was evaluated at a clinic for sexually transmitted diseases. All teenagers and young adults treated for gonorrhea (or as contacts of patients with gonorrhea) who were given a test-of-cure appointment were eligible to participate; in order to win, they had to keep the appointment. The return rate was documented during a baseline and a lottery phase for 519 patients. Females were significantly more likely to keep the appointment (47%) than males (27%), regardless of intervention, but there was no improvement in the return appointment rates with the lottery (baseline, 31% vs. lottery, 33%). Although teenaged males were more likely to participate in the lottery than young adult males and all females, only young adult females who participated were significantly more likely to return (68%). Reasons for failure of the lottery are discussed. Thus, despite the successful use of a lottery in previous studies, it is not always helpful in improving compliant behavior in certain populations.

Adolescent↗