Predicting quantitative phytochemical markers in single Echinacea plants or clones from their DNA fingerprints.

Amplified restricted fragment length polymorphism (AFLP) data analysis was found to be a statistically significant predictor of phytochemical markers in cultivated Echinacea purpurea germplasm and some related wild species. Over 50 accessions grown under greenhouse conditions were subjected to AFLP analysis and the same assessed for content of tetraene and cichoric acid by high pressure liquid chromatography. The first and second canonical correlation of DNA variables and the phytochemical variables were significant. Individual regressions of cichoric acid and dodeca-2E, 4E, 8Z, 10E/Z-tetraenoic acid isobutyl amide predicted by DNA polymorphism analysis against actual HPLC determined values were nearly linear. Mantel's test showed that there was a weak correlation but a strong association of values of the phytochemical variables and the DNA polymorphism data.

A Canadian tertiary care centre study of maternal and umbilical cord cotinine levels as markers of smoking during pregnancy: relationship to neonatal effects.

This study describes the prevalence of smoking among 3,220 pregnant women. Maternal and umbilical cord cotinine levels were compared with the women's self-reported cigarette consumption, infant birth weight and antepartum and perinatal complications. Of the women who reported themselves as being active smokers (23%), 76% had a partner who smoked, and 38% reported exposure to environmental smoke in the workplace. Only 15% of nonsmokers had a partner who smoked, and 13% reported workplace exposure. The mean number of cigarettes/day was 20.5 (95% CI 19.6-21.4). The relative risk of having a small-for-gestational-age infant was significantly higher in smokers for mothers of both preterm (34-36 wks, RR = 3.38, 95% CI 1.25-9.16) and term babies (> or = 37 wks, RR = 2.04, 95% CI 1.58-2.63). Mean infant birth weight was 207 g lighter in the infants of smokers (p < 0.001) and was inversely correlated to maternal serum cotinine level. Birth weight dropped by 0.99 g for every 1 ug/L increase in cotinine (r = -0.19, p < 0.01).

Simultaneous determination of alcohols and ethylene glycol in serum by packed- or capillary-column gas chromatography.

We developed a packed-column chromatographic procedure capable of simultaneous quantitation of methanol, ethanol, isopropanol, acetone, and ethylene glycol. This method was then updated to a rapid, sensitive, wide-bore capillary method. The packed-column system uses direct injection of 1 microL of Na2WO4/H2SO4-deproteinized serum onto a 1.8 m x 2 mm (i.d.) column packed with 80/100 HayeSep R. A linear temperature gradient from 90 to 205 degrees C allows complete elution of all components within 20 min; minimum detection limits are 2 mmol/L. The wide-bore capillary method uses 0.1 microL of sample deproteinized by ultrafiltration, injected onto a 30 m x 0.53 mm (i.d.) 3-microns Rtx-200 (Restek) column. Baseline resolution to a minimum detection limit of 0.1 mmol/L of all compounds is achieved in 5 min with a linear temperature gradient from 40 to 250 degrees C and dual internal standards of n-propanol and 1,2-butanediol.

Reference intervals for 21 clinical chemistry analytes in arterial and venous umbilical cord blood.

Reference intervals were determined for 21 clinical chemistry analytes in umbilical cord arterial and venous blood from healthy term infants. Nonparametric analysis (rank number) was used to determine the central 95% reference interval. No significant differences were observed between male and female infants. Reference intervals for glucose, urea, creatinine, urate, phosphate, calcium, albumin, total protein, cholesterol, triglycerides, alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, creatine kinase, lactate dehydrogenase, gamma-glutamyltransferase, and magnesium all were significantly different from adult values.

A rapid high-performance thin-layer chromatographic urine screen for laxative abuse.

Laxative abuse, if unrecognized, can lead to unnecessary and costly investigations. The stimulants and cathartics are the most commonly abused laxatives and have the potential for causing the most long-term damage. We have optimized a solid-phase extraction coupled with high-performance thin-layer chromatography (HPTLC) to provide rapid, simple, and sensitive detection of phenolphthalein, danthron, rhein, aloin, and bisacodyl and its metabolites in urine. Positive screens have revealed laxative abuse in 3 of 42 samples from patients presenting with diarrhea of unknown origin.

High-performance liquid-chromatographic method compared with a modified radioimmunoassay of cotinine in plasma.

Cotinine is a sensitive and specific biochemical marker of exposure to cigarette smoke. We describe a simple solid-phase extraction of cotinine from plasma before quantification by HPLC. Extraction recovery was 97.9% +/- 11.0% for plasma concentrations of 5-400 micrograms/L. Baseline separation of cotinine and caffeine was achieved within 11 min of injection onto a C18 reversed-phase column. The mobile phase was citric acid/dibasic potassium phosphate (30 mmol/L each, pH 6.0) containing 100 mL of acetonitrile per liter. Within-day and day-to-day precision (CV) were 4.7% and 8.4%, respectively. We also describe a modification of the Nicotine Metabolite RIA kit (Diagnostic Products Corp.) for quantifying cotinine in plasma. Recovery of cotinine from supplemented plasma was within 10% of the expected value with this RIA kit. Interassay precision averaged 8.1% for samples in the range 50-400 micrograms/L; intra-assay precision averaged 3.6% at 230 micrograms/L and 8.7% at 53 micrograms/L. Correlation between the two methods was RIA = 1.13 HPLC + 14.8 (n = 128, r = 0.957, P less than 0.001). Both methods are technically simple to perform.

Endotoxin induction of tumor necrosis factor is enhanced by acid-labile interferon-alpha in acquired immunodeficiency syndrome.

High levels of an acid-labile IFN-alpha have been demonstrated in the sera of patients with symptomatic HIV infection. IFNs have been shown to enhance the cytotoxic and antiproliferative actions of tumor necrosis factor (TNF), which is a potent mediator of inflammation and sepsis. We show that the acid-labile IFN-alpha present in AIDS sera can induce TNF synthesis and sensitize blood monocytes (BM) to endotoxin stimulation resulting in further synthesis of TNF in vitro. TNF production by BM from patients with HIV infections and normal controls was measured by a cytotoxicity assay on L929 cells using human TNF alpha as a standard. BM from AIDS patients spontaneously produce high levels of TNF and are hypersensitive to endotoxin stimulation, resulting in enhanced synthesis of TNF. In determining the mechanism involved, we demonstrated that treatment of normal BM with AIDS sera results in induction of TNF. Neutralization of the acid-labile IFN-alpha in AIDS sera with polyclonal anti-IFN-alpha antibodies results in diminution of TNF induction. In addition, pretreatment of normal BM with AIDS sera, IFN-alpha, or IFN-gamma renders the cells hypersensitive to endotoxin. Consequently, activation of the TNF system by the acid-labile IFN-alpha contributes to some of the physiological disturbances, such as the wasting syndrome, and to the pathophysiology of sepsis in AIDS patients.