An algorithm for detecting features of the hormone profiles of the human menstrual cycle.

An algorithm for detecting features of the cycles of the gonadotropic and ovarian hormones in women is described. The algorithm can detect hormone peaks and normal cycles defined in terms of the peaks in sequences of measurements that have an arbitrary starting point in the menstrual cycle and are of arbitrary length. The algorithm makes use of fuzzy set theory and is optimized using signal detection theory.

Measuring endocrine profiles of women in field studies.

Improved methods are needed to evaluate the effects of occupational and environmental hazards on the reproductive health of human female populations. This communication describes highly specific, sensitive, and reliable time-resolved fluorescence immunoassays for measuring luteinizing hormone (LH) and follicle-stimulating hormone (FSH), estrone 3-glucuronide (E13G), and pregnanediol 3-glucuronide (Pd3G) in urine, a fluid that is convenient and painless to collect serially from large populations. Furthermore, some of the technical issues relevant to the successful application of these measurements to field studies are discussed.

Detecting pre-ovulatory luteinizing hormone surges in urine.

The study objectives were to determine (i) if pre-ovulatory luteinizing hormone (LH) surges, undetected in urine by two immunoradiometric assays (IRMA), were detectable by an ultrasensitive immunofluorometric assay (IFMA) and (ii) the influence of creatinine adjustment on the detection and timing of the urinary LH surges. Daily urine specimens were contributed by healthy 25-36 year old volunteers during 14 ovulatory menstrual cycles for an epidemiological study conducted in 1983-1985. Specimens were selected as having been previously assayed by two IRMA without consistently detecting LH surges. These urine specimens were remeasured using an IFMA and adjusted for creatinine concentration. IFMA measurements revealed unambiguous LH surges in all cycles. Adjusting IRMA urinary LH values for creatinine concentrations revealed previously undetected LH surges in four of eight cycles. Creatinine adjustment also altered the timing of IRMA and IFMA LH surges by 1-5 days. These results demonstrate an IFMA that detects pre-ovulatory LH surges in unpreserved, frozen urine from cycles where such surges were previously undetectable. Further, creatinine adjustment can markedly affect detection and timing of the onset and peak of the urinary LH surge. While our analysis suggests that this adjustment improves the validity of the LH measure, this requires further investigation.

Application of a method for estimating day of ovulation using urinary estrogen and progesterone metabolites.

Longitudinal epidemiologic studies of menstrual and reproductive function are more informative if one can identify day of ovulation. We previously developed a method for estimating day of ovulation that is feasible for epidemiologic studies. The method relies on the relative concentrations of estrogen and progesterone metabolites in daily first-morning urine specimens and does not require creatinine adjustment. This paper describes results of applying this method to a large study with 724 menstrual cycles from 217 women. The method estimated a credible day of ovulation in 88% of cycles. Missing data accounted for most of the failures. When we excluded anovulatory cycles (1%) and cycles with missing data, the method estimated a day of ovulation in 97% of cycles. Variance in luteal phase length was small for our sample, suggesting that this method of identifying a day of ovulation introduces no more measurement error than when day of ovulation is determined by plasma luteinizing hormone (LH), the standard clinical method.

Stability of urinary female reproductive hormones stored under various conditions.

Urinary reproductive hormones afford specific and sensitive evaluation of female reproductive potential in epidemiologic and clinical settings. The goal of this study was to characterize the stability of urinary luteinizing hormone, follicle stimulating hormone, estrone 3-glucuronide, pregnanediol 3-glucuronide, and creatinine during storage as functions of time, temperature, and additives. After 2 weeks with no additives, activity of the four analytes, relative to initial concentrations, ranged from 91.9 to 102.8% at 4 degrees C, 35.1 to 89.6% at 25 degrees C, and 7.5 to 66.9% at 37 degrees C. Antimicrobial additives did not consistently improve stability. Analyte activity for samples stored with no additives for 24 weeks at -80 degrees C ranged from 69.0 to 101.2%. Glycerol and bovine serum albumin improved analyte stability; activity ranged from 91.1 to 106.3%. Other additives were ineffective. These results reveal conditions for storing reproductive hormone analytes in urine during epidemiologic field studies.

Validations of time-resolved fluoroimmunoassays for urinary estrone 3-glucuronide and pregnanediol 3-glucuronide.

Competitive time-resolved fluoroimmunoassays (FIAs) were developed for measuring 1,3,5(10)-estratrien-3-ol-17-one glucosiduronate (estrone 3-glucuronide, E(1)3G) and 5 beta-Pregnane-3 alpha,20 alpha-diol 3-glucosiduronate (pregnanediol 3-glucuronide, Pd3G) in unextracted urine. The assays are specific, detect 0.98 ng E(1)3G/mL and 0.035 microgram Pd3G/mL, measure 102.8 +/- 2.0% of E(1)3G and 93.6 +/- 2.9% of Pd3G added, and exhibit between and within assay coefficients of variation, respectively, of 5.3% and 7.1% for E(1)3G and 6.8% and 7.8% for Pd3G. The urine matrix does not interfere with the assay. Urinary steroid glucuronide profiles measured by these FIAs conform to those of urinary steroid glucuronides and serum estradiol and progesterone measured by other established immunoassays. These FIAs afford the advantages of non-radioisotopic procedures and urine sample collection (convenience, non-invasiveness, integration of pulsatile secretion) to evaluate menstrual function in epidemiological, medical, and athletic populations.

Pulmonary reactivity to vanadium pentoxide following subchronic inhalation exposure in a non-human primate animal model.

An experimental study was conducted to evaluate changes in pulmonary reactivity resulting from repeated vanadium pentoxide (V2O5) dust inhalation. The study assessed pulmonary reactivity to V2O5 through the use of provocation challenges, and compared V2O5 reactivity before and after subchronic V2O5 exposure. A total of 24 adult, male cynomolgus monkeys (Macaca fascicularis) were exposed by inhalation for 6 h per day, 5 days per week, for 26 weeks. Two V2O5-exposed groups (n = 8 each) received equal weekly V2O5 exposures (concentration x time) with different exposure profiles. One V2O5-exposed group received 0.1 mg V2O5 m-3 on Mondays, Wednesday and Fridays, with a twice-weekly peak exposure of 1.1 mg V2O5 m-3 on Tuesdays and Thursdays, and was included to investigate the influence of an exposure regimen with peaks on the development of pulmonary hyper-reactivity. The other V2O5-exposed group received a constant daily concentration of 0.5 mg V2O5 m-3. A control group (n = 8) received filtered, conditioned air. Pre-exposure challenges with V2O5 produced a concentration-dependent impairment in pulmonary function, characterized by airway obstructive changes (increased resistance and decreased flow). Analysis of respiratory cells recovered from the lung by bronchoalveolar lavage demonstrated that airway obstruction was accompanied by a significant influx of inflammatory cells into the lung. Subchronic V2O5 inhalation did not produce an increase in V2O5 reactivity in comparison to the control group, and cytological, immunological and skin test results indicate the absence of allergic sensitization. Instead, a trend toward decreased pulmonary reactivity was found following subchronic V2O5 inhalation.(ABSTRACT TRUNCATED AT 250 WORDS)

Evaluation of the onset and duration of response to cold air inhalation challenge in cynomolgus monkeys (Macaca fascicularis).

Cold air inhalation challenge (CAIC) for the evaluation of bronchial reactivity has been proposed as a physical agent alternative to chemical agent challenges (methacholine or histamine), especially suitable for the occupational environment. The present investigation describes and evaluates a method for performing cold air inhalation challenge in Cynomolgus monkeys (Macaca fascicularis), a species shown to be useful in animal modeling studies of occupational asthma. Six adult male anesthetized monkeys were ventilated by changes in external pressure while breathing cold air (-25 degrees C to -30 degrees C). Pulmonary function testing was performed at 10, 25, 40 and 55 min post-challenge. Significant increases (P less than 0.05) in average pulmonary flow resistance (RL) and decreases in dynamic compliance (CL dyn) were observed, with maximum impairment occurring at 25 min post-challenge, with a trend towards a return to baseline values at 55 min post-challenge. Peak expiratory flow rate (PEFR), forced expiratory volume in 0.5 s/forced vital capacity (FEV0.5/FVC) and forced expiratory flow at 50% forced vital capacity (FEF50) showed the same general pattern of reduction as seen with RL; however, these results were not statistically significant, most probably owing to individual monkey variability and the small number of monkeys (N = 6) used. A repeat challenge at 25 min after a primary challenge yielded increased RL in one monkey, suggesting that no absolute refractory period is present from CAIC. Results of these studies demonstrate that CAIC causes bronchoconstriction in monkeys and may be useful in further animal modeling studies designed to determine the asthmogenic/airway irritant potential of occupational toxicants.

Acute airway narrowing in monkeys from challenge with 2.5 ppm formaldehyde generated from formalin.

Nine adult male Cynomolgus monkeys (Macaca fascicularis) were exposed for 10 min to 2.55 +/- 0.03 ppm formaldehyde (HCHO; mean +/- standard error of the mean, SEM) generated from formalin with a newly developed HCHO challenge system. The generation system was capable of producing highly stable HCHO vapor concentrations with fluctuations of HCHO concentrations of less than +/- 5%. The experimental design included pre-exposure methacholine challenge to determine if responses to HCHO were associated with pre-existing bronchial hyperreactivity. Significant changes in average pulmonary flow resistance (RL) were observed (compared to control RL values) at 2 (p less than 0.01), 5 (p less than 0.01), and 10 min (p less than 0.005) post-HCHO challenge. Pre-challenge RL values (mean +/- SEM) were 11.3 +/- 1.4 cm H2O.l/s, while at 2, 5, and 10 min after HCHO challenge, values were 16.1 +/- 2.1, 16.9 +/- 2.8 and 20.0 +/- 3.4 cm H2O.l/s, respectively. Methacholine challenge data suggest that reactions to HCHO tend to be greater in monkeys hyperreactive to methacholine, but the relationship does not reach statistical significance in this small series of animals. These data indicate that significant pulmonary function deficits occur immediately after challenge with 2.55 ppm HCHO vapor in monkeys.

Immune responses of cynomolgus monkeys to phthalic anhydride.

Four groups of four Macaca fascicularis monkeys were administered 10 consecutive weekly subcutaneous injections of 2 mg aluminum hydroxide plus one of the following: 200 micrograms of phthalic anhydride (PA)-monkey serum albumin (PA-MSA, group 1); 200 micrograms of PA dissolved in ethanol-saline (EtOH-sal, group 2); 200 micrograms of MSA (group 3); or EtOH-sal alone (group 4). Direct intracutaneous tests to PA-MSA, PA-EtOH-sal, MSA, and EtOH-sal were applied at biweekly intervals throughout the course of the immunization. Serum-specific IgG to PA-MSA and specific IgE to PA-MSA were determined at 2-week intervals according to the ELISA and RAST methods, respectively. The prevalence of cutaneous sensitivity to PA-MSA in the PA-MSA-immunized group (group 1) was significantly greater after 4 and 6 (p less than 0.01) and 8 and 10 (p less than 0.05) weeks, compared with the other treatment groups. Significantly elevated (p less than 0.01) PA-MSA-specific IgG was also observed in monkeys in group 1 compared with the other treatment groups. No significant changes in PA-MSA RAST or total IgE were observed in any group during the study. These results indicate that parenteral sensitization to PA in subhuman primates requires the presence of new antigenic determinants formed by PA on protein carriers.

Pulmonary effects of acute vanadium pentoxide inhalation in monkeys.

An experimental study was conducted to investigate the hypothesis that changes in pulmonary function induced by vanadium pentoxide (V2O5) inhalation would be accompanied by evidence of pulmonary inflammation. Sixteen adult, male cynomolgus monkeys were acutely exposed by whole-body inhalation of V2O5 dust at aerosol concentrations of 0.5 mg V2O5/m3 and 5.0 mg V2O5/m3, conducted at a 1-wk interval. Comprehensive pulmonary function tests were performed 1 day after each inhalation exposure to detect functional changes in the airways and pulmonary parenchyma. Pulmonary inflammation was assessed by cytologic analysis of respiratory cells recovered from the lower respiratory tract by bronchoalveolar lavage (BAL). Postexposure values for pulmonary function and BAL were compared with the baseline values determined for each monkey prior to V2O5 exposure. Acute V2O5 dust inhalation produced significant air-flow limitation in both central and peripheral airways without producing any detectable changes in parenchymal function. These functional changes were accompanied by a significant increase in the total cell counts recovered from the lungs by BAL. The increase in total cell count occurred through a dramatic increase in absolute number and relative percentage of polymorphonuclear leukocytes (PMN). These findings suggest that pulmonary inflammatory changes involving PMN may play an important role in the occurrence of air-flow limitation after acute inhalation of V2O5 dust.

Thermoregulatory ability of female rats during pregnancy and lactation.

Thermoregulatory ability of female rats was examined before pregnancy, during gestation, and during lactation. Thermoregulatory pattern, colonic temperature, evaporative water loss, and survival time were monitored during terminal heating (39.5 +/- 0.9 degrees C) designed to allow prolonged survival (3-4 h) with a sustained thermoregulatory effort. Results confirmed our previously reported observation of decreased thermoregulatory ability in lactating dams, with evidence suggesting thermoregulatory impairment during late gestation. Lactating dams displayed a type III thermoregulatory pattern, and established a rate of evaporative water loss effective for thermostasis at an elevated colonic temperature. However, survival time was significantly decreased compared to nonreproducing females. In contrast, prior heat acclimation tended to increase the survival time of lactating dams. It was concluded that the reduction in thermoregulatory ability observed in lactating dams was related to their inability to maintain a rate of evaporative water loss effective for thermostasis at an elevated colonic temperature.

Effect of heat exposure on in vitro intestinal transport and utilization of glucose in the rat.

Intestinal transport and utilization of glucose were studied in vitro in chronically heat-exposed (Ta = 34 degrees C) rats. Despite mucosal tissue per centimetre being significantly reduced following 7 and 14 days of exposure, no differences from control values were noted in full serosal to mucosal (S/M) fluid glucose concentrations ratios obtained from everted sac preparations. Measurements on 40-cm jejunal segments perfused in vitro at days 13-15 showed a reduction in the rate of glucose absortpion per centimetre of intestine, while glucose absorption per gram of tissue was unaltered in heat-exposed rats. At the same time, glucose secretion at the serosal surface was unchanged as calculated per centimetre of intestine and increased when calculated per gram of dry tissue. The utilization of glucose by the intestine was found to be significantly reduced whether expressed for intestinal length or for intestinal weight. In addition, the glucose concentration of the tissue water was elevated in intestinal segments of heat-exposed rats after 60 min of perfusion. The decrease in glucose uptake per centimetre of intestine was attributed to the decrease in mucosal tissue. Elevated tissue glucose concentration and enhanced translocation of glucose to the serosal surface were attributed, at least in part, to the decreased rate of glucose metabolism observed in intestines of heat-exposed rats.

Periodic, short-term heat exposure and reproductive function in male and female rats.

Reproductive function of male and female rats was examined in relation to periodic, short-term heat treatment. Daily exposure to an environmental temperature of 38.2 degrees C for 55 min elevated rectal temperatures to 39.9 and 41.2 degrees C in male and female rats, respectively. Heat exposure tended to decrease copulation in males cohabitated with unheated females. The rate of conception was affected similarly, and fetal survival tended to be reduced by paternal heat treatment. Estrous cycles were disrupted initially in heat-exposed females, but the rate of copulation and conception of females cohabitated with unheated males was unaltered by heat treatment. However, maternal heat exposure impaired prenatal survival and growth. During lactation, a high incidence of maternal and pup deaths was observed at approximately 14 days postpartum. Maternal deaths were coincident with a decrease in thermoregulatory ability and rectal temperatures exceeding 42 degrees C.