1H NMR, a rapid method to monitor organic acids during cupuassu (Theobroma grandiflorum Spreng) processing.

The development of an analytical method using 1H nuclear magnetic resonance (1H NMR) spectrometry to monitor cupuassu (Theobroma grandiflorum Spreng) bean fermentation, drying, and roasting processes is reported. The analysis of organic acids and alcohols of crude water extracts of cupuassu ground kernels were monitored by HPLC and 1H NMR spectroscopy. The residual protein signals caused deleterious effects on acid and alcohol quantifications. Therefore, the analytical procedures were optimized by sample cleanup and water suppression pulse sequences in order to obtain compatible data using HPLC and 1H NMR. The quantification of lactic acid, acetic acid, and 2,3-butanediol by NMR is 5- to 10-fold faster than by HPLC, with the advantage of providing the identification of several chemical species in a single experiment. Application of these analytical conditions to some cupuassu samples revealed that this methodology can be applied to the quality profiles of fermentation and roasting processes.

Biodegradation kinetics for pesticide exposure assessment.

Understanding pesticide risks requires characterizing pesticide exposure within the environment in a manner that can be broadly generalized across widely varied conditions of use. The coupled processes of sorption and soil degradation are especially important for understanding the potential environmental exposure of pesticides. The data obtained from degradation studies are inherently variable and, when limited in extent, lend uncertainty to exposure characterization and risk assessment. Pesticide decline in soils reflects dynamically coupled processes of sorption and degradation that add complexity to the treatment of soil biodegradation data from a kinetic perspective. Additional complexity arises from study design limitations that may not fully account for the decline in microbial activity of test systems, or that may be inadequate for considerations of all potential dissipation routes for a given pesticide. Accordingly, kinetic treatment of data must accommodate a variety of differing approaches starting with very simple assumptions as to reaction dynamics and extending to more involved treatments if warranted by the available experimental data. Selection of the appropriate kinetic model to describe pesticide degradation should rely on statistical evaluation of the data fit to ensure that the models used are not overparameterized. Recognizing the effects of experimental conditions and methods for kinetic treatment of degradation data is critical for making appropriate comparisons among pesticide biodegradation data sets. Assessment of variability in soil half-life among soils is uncertain because for many pesticides the data on soil degradation rate are limited to one or two soils. Reasonable upper-bound estimates of soil half-life are necessary in risk assessment so that estimated environmental concentrations can be developed from exposure models. Thus, an understanding of the variable and uncertain distribution of soil half-lives in the environment is necessary to estimate bounding values. Statistical evaluation of measures of central tendency for multisoil kinetic studies shows that geometric means better represent the distribution in soil half-lives than do the arithmetic or harmonic means. Estimates of upper-bound soil half-life values based on the upper 90% confidence bound on the geometric mean tend to accurately represent the upper bound when pesticide degradation rate is biologically driven but appear to overestimate the upper bound when there is extensive coupling of biodegradation with sorptive processes. The limited data available comparing distribution in pesticide soil half-lives between multisoil laboratory studies and multilocation field studies suggest that the probability density functions are similar. Thus, upper-bound estimates of pesticide half-life determined from laboratory studies conservatively represent pesticide biodegradation in the field environment for the purposes of exposure and risk assessment. International guidelines and approaches used for interpretations of soil biodegradation reflect many common elements, but differ in how the source and nature of variability in soil kinetic data are considered. Harmonization of approaches for the use of soil biodegradation data will improve the interpretative power of these data for the purposes of exposure and risk assessment.

Sonohysterographic screening before in vitro fertilization.

OBJECTIVE: To evaluate the use of sonohysterography for uterine screening before IVF. DESIGN: Prospective screening with sonohysterography and comparison with available hysterosalpingographic and hysteroscopic evaluations. SETTING: Private practice. PATIENT(S): Seventy-two women undergoing IVF-ET using their own or donor eggs. INTERVENTION(S): Sonohysterography was performed by instilling saline into the uterine cavity through an intracervical balloon catheter; there was concurrent vaginal sonographic visualization in all cases. MAIN OUTCOME MEASURE(S): Sonohysterographic findings and pregnancy rates. RESULT(S): Cavitary lesions were detected in 8 (11.1%) of 72 sonohysterographic examinations. Six of 8 cases were confirmed and treated by hysteroscopy. After sonohysterographic evaluation, 35 (48.6%) of 72 patients conceived, resulting in 25 ongoing or delivered pregnancies, 5 chemical pregnancies, and 5 spontaneous abortions. No statistically significant difference was observed in the pregnancy outcome for patients undergoing IVF who had sonohysterography compared with that for patients undergoing IVF during the same period who previously had a uterine evaluation by a different method. The estimated cost savings per patient undergoing sonohysterography instead of in-office hysteroscopy was $275. CONCLUSION(S): Sonohysterography offers advantages over in-office hysteroscopy and hysterosalpingography for evaluation of the uterus before IVF.

Surgical treatment of endometriosis.

Surgical resection of endometriosis, previously possible only by means of laparotomy, can now be accomplished through laparoscopic techniques. The requirements for surgery, surgical principles, operative techniques, and results are summarized in this article, with emphasis on the laparoscopic approach.

Human fetal adrenal definitive and fetal zone metabolism of pregnenolone and corticosterone: alternate biosynthetic pathways and absence of detectable aldosterone synthesis.

In the rhesus monkey and ovine fetus in utero, aldosterone concentrations do not rise in response to surgical stress, ACTH, or angiotensin-II, all of which are secretagogues for this mineralocorticoid in the adult. To assess the mechanism of this phenomenon in the human fetus, metabolism of pregnenolone and corticosterone by second trimester human fetal adrenal definitive zone and fetal zone tissue was studied. After incubation of fresh tissue with trace amounts of [3H]pregnenolone or [3H]corticosterone, the products of metabolism were separated using high performance liquid chromatography and quantified. The delta 5-3 beta-hydroxysteroids 17-hydroxypregnenolone and dehydroepiandrosterone and their sulfates comprised 85-90% of metabolized pregnenolone. In the fetal zone, cortisol was the predominant secreted delta 4-3-ketosteroid, accounting for 6-8% of the metabolized pregnenolone. In the definitive zone, progesterone and corticosterone were the predominant secreted delta 4-3-ketosteroids, each accounting for about 2% of the metabolized pregnenolone. 11-Dehydrocorticosterone and sulfates were the only metabolites detected after incubation of fetal adrenal tissue with corticosterone. 11-Dehydrocorticosterone accounted for more than 80% of the metabolized corticosterone in the definitive zone and 50% in the fetal zone. Incubations with secretagogues or antioxidants (10 nmol/L ACTH, 10 nmol/L angiotensin-II, 21 mmol/L potassium, 100 mmol/L dimethylsulfoxide, 5 mumol/L metyrapone, or 100 mumol/L butylated hydroxyanisole) did not change the pattern or extent of precursor metabolism. No aldosterone, 18-hydroxycorticosterone, or 18-hydroxydeoxycorticosterone was detected in baseline or stimulated incubations of human fetal tissue. In contrast, adult human zona glomerulosa metabolized corticosterone to aldosterone, 18-hydroxycorticosterone, and 11-dehydrocorticosterone under similar conditions.(ABSTRACT TRUNCATED AT 250 WORDS)

Independent associations of bacterial vaginosis and Chlamydia trachomatis infection with adverse pregnancy outcome.

We prospectively studied the relationship of pregnancy outcome to bacterial vaginosis, an anaerobic vaginal condition, and to other selected genital pathogens among 534 gravid women. Bacterial vaginosis was presumptively diagnosed by gas-liquid chromatographic identification of microbial organic acid metabolites in 102 women (19%), and cervical infection with Chlamydia trachomatis was found in 47 (9%) of the women. Although women with and without bacterial vaginosis had similar demographic and obstetric factors, neonates born to women with bacterial vaginosis had lower mean birth weight than did neonates born to women without bacterial vaginosis (2960 +/- 847 g vs 3184 +/- 758 g). Bacterial vaginosis was significantly associated with preterm premature rupture of the membranes (odds ratio [OR], 2.0; 95% confidence interval [Cl], 1.1 to 3.7), preterm labor (OR, 2.0; Cl, 1.1 to 3.5), and amniotic fluid infection (OR, 2.7; Cl, 1.1 to 6.1), but not with birth weight below 2500 g (OR, 1.5; Cl, 0.8 to 2.0). Cervical infection with C trachomatis was independently associated with preterm premature rupture of the membranes, preterm labor, and low birth weight (OR, 1.5; Cl, 0.8 to 2.0).