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B E Statland

Publications and source records attributed to B E Statland.

At least 91 records · Page 5Linked to original sources
PubMed1982

Diagnostic reliability of the lecithin/sphingomyelin ratio assay and the quantitative foam stability index test: results of a comparative study.

We analyzed 331 pregnancies where clear, uncontaminated amniotic fluid was obtained within 72 hours of delivery from both normal and complicated gestations. There were 43 cases of the neonatal idiopathic respiratory distress syndrome (IRDS), 42 of which were associated with foam stability index (FSI) values of less than 0.47. In 276 of the 323 cases sufficient amniotic fluid was available to permit concurrent performance of the lecithin/sphingomyelin ratio (L/S) assay. Thirty-five cases of IRDS occurred in this group, 8 of which were associated with L/S ratio values greater than 2.0. The risk of IRDS occurrence was calculated for three groups of FSI values (shown in parentheses below). They were as follows: group I--FSI values less than or equal to 0.43 (73%); group II--FSI values of 0.44 to 0.46 (29.2%); group III--FSI values greater than or equal to 0.47 (0.35%). Comparable evaluations for the L/S ratio procedure showed the FSI test to be significantly more specific and sensitive than the L/S ratio assay. The improved performance of the FSI test was most marked in pregnancies complicated by insulin-dependent diabetes mellitus and intrauterine growth retardation. The low cost, ease and rapidity of the FSI test, as well as the fact that it does not require sophisticated technical equipment or expertise, makes this sensitive and specific assay a method of choice for the prenatal evaluation of fetal pulmonary maturity.

Amniotic Fluid↗
PubMed1982

Predicting recurrence in patients with breast cancer from cumulative laboratory results: a new technique for the application of time series analysis.

We followed the cases of 26 consecutive postmenopausal patients operated on for primary breast cancer. Serum specimens were obtained each month for 1.5 years and stored at -80 degrees C until assayed for carcinoembryonic antigen (CEA) and other quantities. Ten patients developed recurrence, while 16 qualified as controls (no clinical recurrence for at least 1.7 years after the last venipuncture). Using the homeostatic autoregressive time series model, modified by us to be particularly sensitive to sustained deviations from the mean, we detected four recurrences by CEA without having any falsely positive alarms. Group-based reference limits and application of the unmodified homeostatic model were less effective (fewer detected and shorter lead time). Simulation studies, involving use of a mathematical model relating CEA concentration to tumor growth and using parameters estimated from patient data, verified this and indicated that at least five stable baseline values are needed to detect 100% of recurrences before they are detected by the group-based limit.

Aged↗
PubMed1981

Within-day physiologic variation of leukocyte types in healthy subjects as assayed by two automated leukocyte differential analyzers.

The physiologic within-day (700-2200 h) variation of leukocyte-type concentrations in blood as determined for 21 healthy young adults is reported. All blood specimens were obtained in duplicate such that the within-batch analytic variation, as well as the pertinent biologic sources of variation, was able to be determined. All specimens were analyzed on each of two automated leukocyte differential systems: Hemalog-D Differential System and the Hematrak-240 Analyzer. On the basis of a comparison of the performances of the two analyzers, it was decided to report the neutrophil and the lymphocyte values as measured on both systems, the monocyte values as measured on teh Hematrak only, and the eosinophil and basophil values as measured on the Hemalog-D only. The intrasubject within-day physiologic variations for the cell on the Hemalog-D and Hematrak, respectively, in terms of coefficient of variation wee as follows: neutrophils 19.4% and 19.6%; lymphocytes, 13.8% and 17.5%. For monocytes, as measured on the Hematrak, it was 13.4%. For eosinophils and basophils, as measured on the Hemalog-D, it was 27.2% and 8.3%, respectively. There was a consistent group-specific diurnal variance that amounted to more than 40% of the total within-day variance, both for lymphocytes and for eosinophils. The within-day physiologic variation of the cell type concentrations for eight of the volunteers was compared with that of the plasma cortisol concentrations, as determined on specimens derived from the same veni-puncture sessions. The decrease in plasma cortisol values was in most instances associated with decreases in eosinophils and increases in neutrophils. For total leukocytes and neutrophils, the mean concentration for smokers was significantly higher than that for nonsmokers.

Adult↗
PubMed1981

The acute effect of cigarette smoking on the concentrations of blood leukocyte types in healthy young women.

The acute effect of cigarette smoking on blood leukocyte values in four healthy young women is reported. In a cross-over experiment using the Hemalog-D automated differential system, the effect of smoking four to 12 cigarettes on the time course of the concentration of leukocyte types was studied. During each of two experiments lasting from 800 h to 1400 h, the subjects were in the supine position. Each subject abstained from smoking during one experimental day and started smoking at 930 h on the other experimental day. The values obtained during each experimental day were expressed for each subject as change from the baseline values measured before 930 h. The time course for the lymphocyte concentration changed significantly (P less than 0.05) on the day of smoking as compared with the day of not smoking, showing an initial elevation followed by a more prolonged depression. The eosinophil concentration was uniformly and significantly (P less than 0.05) depressed. The neutrophil concentration showed a delayed response, with an elevation starting at 1200 h. The latter effect, however, was of borderline significance (P = 0.07).

Adult↗
PubMed1981

Measurement of amniotic fluid surfactant.

Measurement of the production of surfactant is the most direct means of prenatally assessing fetal pulmonary maturity. We review assays which have evolved for measuring surfactant, classifying them into two general categories: biochemical quantitation and biophysical measurements. Biochemical quantitation assays include the amniotic fluid lecithin/sphingomyelin ratio and quantitation of lecithin and other surfactant phospholipids. Biophysical measurements include measurement of surface-tension-lowering ability of extracts of amniotic fluid lipid and evaluation of surface-tension-related properties such as foam stability and microviscosity. Assays of surfactant are subject to certain pre-analysis sources of variation over which the analyst has no control, such as variability in total in vivo amniotic fluid volume, incomplete in vivo mixing of surfactant with amniotic fluid, and presence of contaminating blood or meconium. We also examine other factors such as centrifugation speed and time, and storage of the amniotic specimen before analysis. These factors can dramatically affect analyses, and must be carefully controlled by the analyst. In general, both biochemical and biophysical approaches to surfactant analysis are useful diagnostically. When properly performed, both approaches give results that correlate well, both with each other and with clinical outcome. Because "mature" and "immature" values overlap, none of the assays can completely eliminate false predictions, whether of fetal maturity or fetal immaturity.

Amniotic Fluid↗
PubMed1981

Centrifugal analysis for plasma kallikrein activity, with use of the chromogenic substrate S-2302.

The amidolytic activity of activated kallikrein in plasma can be measured by use of the chromogenic substrate, S-2302 (H-D-Pro-Phe-Arg-pNA). Plasma prekallikrein was activated to kallikrein by exposure to 50 mg/L dextran sulfate in acetone/water (35/65 by vol) at 0 degrees C for 15 min. The acetone slows anti-kallikrein activity and increases the kallikrein activity by 30%. The 37 degrees C reaction mixture contained 0.54 mmol of S-2302 substrate per liter of Tris buffer (pH 7.5 at 37 degrees C). We monitored the change in absorbance at 405 nm for 60 s. The specificity of the substrate for kallikrein was demonstrated by using plasma deficient in prekallikrein (Fletcher trait) diluted with pooled normal human plasma. We recommend collecting blood specimens with sodium citrate as the anticoagulant and with use of a double-syringe technique and all-plastic containers. Plasma kallikrein activity with Chromozym-PK (Bz-Pro-Phe-Arg-pNA) as substrate (y-axis) compared with S-2302 as substrate (x-axis) gave the relation: y = 0.28x + 0.82 (r = 0.94). Day-to-day analytical variation was 2.4% for a pooled plasma with a mean value of 85.9 mukat/L. The mean (and 2 SD) for 50 healthy adults was 86.4 (32.4) mukat/L.

Adult↗
PubMed1981

Evaluation of the small third-trimester fetus using the foam stability index test.

The diagnostic effectiveness of the lecithin:sphingomyelin (L:S) ratio was compared with that of the quantitative amniotic fluid foam stability index (FSI) test in the prenatal evaluation of pregnancies associated with fetuses appropriately grown for gestational age (AGA) and with intrauterine growth retardation (IUGR). In 27 such pregnancies, both the L:S ratio assay and the FSI test were performed on amniotic fluid specimens collected within 72 hours of delivery. Of the 27 low birth weight (LBW) neonates studied, 15 were small for gestational age (SGA) but did not have idiopathic respiratory distress syndrome (IRDS), whereas of 12 AGA neonates, 9 had IRDS. The 15 IUGR cases were characterized by FSI values varying from 0.47 to 0.55, whereas the 12 AGA cases had values varying from 0.42 to 0.48. Thus, the FSI showed excellent differentiation between these 2 entities. The L:S ratio ranged from 1.1 to 3.4 in cases associated with IUGR and from 1.0 to 2.4 in AGA cases, showing a high degree of overlap. The combination of an L:S ratio of less than 1.5 and an FSI value of less than 0.47 consistently identified the fetus who would have IRDS.

Amniotic Fluid↗
PubMed1980

Serum caffeine half-lives. Healthy subjects vs. patients having alcoholic hepatic disease.

Results are presented describing serum caffeine half-lives for three healthy subjects and two patients having alcoholic hepatic disease. The mean serum caffeine half-life for the healthy subjects was 5.7 hours. One patient, a 35-year-old man who had alcoholic hepatic disease, had a serum half-life of 60 hours. The other patient, a 49-year-old woman having alcoholic hepatic disease had a serum half-life of 168 hours. The prolonged serum half-lives for the two patients are explained on the basis of compromised liver function. The serum half-life of caffeine was determined for the three healthy subjects when 25 mg diazepam was given one hour prior to the caffeine load. A significant difference was not found between the serum half-lives measured after diazepam was given and the serum half-life measured when diazepam was not given.

Adult↗
PubMed1980

Serum enzyme alterations in polymyositis. Possible pitfalls in diagnosis.

We report serum enzyme patterns in three patients with polymyositis or dermatomyositis whose cases posed potential problems in distinguishing malignancy, hepatocellular damage, and myocardial infarction from myositis. The alanine aminotransferase showed five- to 16-fold elevations. The creatine kinase MB isoenzyme and a predominance of lactate dehydrogenase isoenzymes 2 and 3 were present in each of the three patients. However, none of the patients showed any evidence of hepatocellular damage, myocardial infarction, or malignancy. We suggest that, although the individual occurrences are indicative of other processes, the concurrence of elevated alanine aminotransferase, creatine kinase MB, and elevated lactate dehydrogenase isoenzymes 2 and 3 is consistent with the diagnosis of polymyositis.

Alanine Transaminase↗
PubMed1980

Clinical evaluation of the quantitative foam stability index test.

The foam stability index (FSI) test for amniotic fluid is a quantitative test that uses ethanol as the antifoaming reagent; it presents values in terms of the highest ethanol volume fraction that will permit stable foam to occur. In this study the authors report on FSI tests results in terms of neonatal outcome in a total of 208 pregnancies in which fluids were obtained within 3 days of delivery. The authors noted a total of 27 cases of hyaline membrane disease (HMD) in their population. All 27 had FSI values of 0.47 or less, whereas 119 of the 181 patients without HMD had FSI values of 0.48 or above. The risk of HMD's occurring was calculated for 4 groups of FSI values. They were as follows: 1) FSI values less than or equal to 0.43 (62%); 2) FSI values of 0.44 and 0.45 (23%); 3) FSI values of 0.46 and 0.47% (14%); and 4) FSI values greater than 0.48 (0%). Comparable evaluations of the lecithin:sphingomyelin (L:S) ratio procedure performed on the same specimens revealed no apparently improved diagnostic reliability. In addition, in several cases of intrauterine growth retardation with normal neonatal respiratory status in which the L:S ratios were less than 1.5, the FSI test correctly predicted fetal lung maturity (FSI greater than or equal to 0.48). The authors conclude that the FSI test has sufficient diagnostic reliability to be considered as a sensitive and specific assay of fetal pulmonary maturation.

Amniotic Fluid↗