Fine particulate matter (PM2.5) air pollution and immune status among women in the Seattle area.

Changes in immune status have been suggested as a possible biologic mechanism by which particulate matter (PM) air pollution could lead to adverse health effects. The authors studied associations between ambient PM2.5 and immune status among 115 postmenopausal, overweight women in the greater Seattle, Washington, area. The authors evaluated 3-day, 30-day, and 60-day average PM2.5 values in relation to inflammation markers (C-reactive protein, serum amyloid A, interleukin-6) and functional assays of cellular immunity (natural killer cell cytotoxicity, T-lymphocyte proliferation) at 3 time points for each woman during 1 year. Three-day averaged PM2.5 was inversely associated with anti-CD3-stimulated lymphocyte proliferation. There were no notable associations between the inflammation markers and PM2.5. If additional studies confirm our findings, then future health effect assessments for PM2.5 should consider changes in cellular immunity as an endpoint that may lead to overt clinical disease.

Serum leptin concentrations and markers of immune function in overweight or obese postmenopausal women.

Experimental studies and case reports suggest a multifunctional role of leptin in immune function. However, clinical studies of leptin in healthy individuals with a comprehensive assessment of immunity are lacking. This study investigated associations between serum leptin concentrations and multiple biomarkers of cellular immunity and inflammation among 114 healthy postmenopausal, overweight, or obese women. Leptin was measured by RIA. C-reactive protein (CRP) and serum amyloid A (SAA) were measured by nephelometry. Flow cytometry was used to measure natural killer (NK) cell cytotoxicity and to enumerate and phenotype lymphocyte subsets. T-lymphocyte proliferation was assessed in response to phytohemagluttinin, as well as to anti-CD3 antibodies by the flow cytometric cell division tracking method. Multiple linear regression analysis with adjustment for confounding factors and log transformation, where appropriate, was used. Serum leptin concentrations were positively associated with serum CRP, SAA, and interleukin 6 (IL6) (P<0.0001, P=0.01, and P=0.04 respectively), more strongly among women with a body mass index (BMI) <30 kg/m(2). The associations were attenuated after adjustment for measured body composition, yet remained significant for CRP and SAA. No statistically significant associations were observed between leptin and NK cytotoxicity, lymphocyte subpopulations, or T-lymphocyte proliferation. This study fills an important gap in knowledge about the relationship between leptin concentrations and immune function in healthy individuals. Findings support an association between serum leptin and the inflammatory proteins CRP and SAA, which appears to be mediated only partly by adipose tissue. Our study does not support a link between leptin and other immune parameters among overweight or obese, but otherwise healthy postmenopausal women, perhaps because such effects are only present at low or deficient leptin concentrations.

Effect of exercise on in vitro immune function: a 12-month randomized, controlled trial among postmenopausal women.

Cross-sectional studies suggest that moderate physical activity is associated with enhanced resting immune function; however, few randomized controlled trials have investigated this link. We investigated the effect of 12-mo aerobic exercise, relative to stretching control, on in vitro immune function in a randomized, controlled trial of 115 postmenopausal, overweight, or obese sedentary women, aged 50-75 yr. The exercise goal was > or =45 min/day, 5 days/wk. Control women participated in 1 day/wk stretching classes. Immune markers (natural killer cell cytotoxicity, T-lymphocyte proliferation, immune cell counts and phenotypes, and serum immunoglobulins) were assessed at baseline, 3 mo, and 12 mo under strict blood-draw criteria. General estimation equations evaluated intervention effects at 3 and 12 mo, controlling for baseline. Of the 115 women who began the trial, blood samples were available from 109 at 3 mo (95%) and 108 at 12 mo (94%). From baseline to 12 mo, the exercise group participated in 87% of the prescribed physical activity minutes per week and increased maximal O(2) uptake by 13.8%; controls experienced no change in fitness. The main outcomes, natural killer cell cytotoxicity and T-lymphocyte proliferation, did not differ between groups at 3 and 12 mo. Secondary outcome and subgroup (e.g., stratification by baseline categories of body mass index, immune status, C-reactive protein, and age) analyses did not show any clear patterns of association. This 12-mo randomized, controlled trial showed no effect of aerobic exercise on in vitro immune function, despite excellent retention, high adherence, and demonstrable efficacy of the exercise intervention.

Associations between healthy eating patterns and immune function or inflammation in overweight or obese postmenopausal women.

BACKGROUND: The link between poor nutritional status and impaired immune function is well established; however, most studies have focused on individual nutrients instead of overall dietary patterns. OBJECTIVE: Our objective was to investigate associations between 3 indexes of overall diet quality [the Diet Quality Index (DQI), the DQI including supplementary calcium (DQI-Ca), and the Healthy Eating Index (HEI)] and biomarkers of inflammation and immunity. DESIGN: This cross-sectional study included 110 overweight or obese postmenopausal women. Dietary intake measured by food-frequency questionnaire was used to calculate diet quality scores. C-reactive protein (CRP) and serum amyloid A (SAA) were measured by latex-enhanced nephelometry. Flow cytometry was used to measure natural killer (NK) cell cytotoxicity and to enumerate and phenotype lymphocyte subsets. T lymphocyte proliferation was assessed by (3)H-thymidine incorporation as well as by the carboxyfluorescein-succinimidyl ester method of cell division tracking. Multivariable-adjusted linear regression analysis was used to investigate associations between diet quality scores and markers of inflammation and immune function. RESULTS: Higher diet quality was associated with increased proportions of cytotoxic and decreased proportions of helper T lymphocytes. CRP and SAA concentrations were higher among women with a lower-quality diet; these associations became nonsignificant after adjustment for body mass index or percentage body fat. We observed limited evidence for an association between healthy eating patterns and greater lymphocyte proliferation and no evidence for an association with NK cell cytotoxicity. CONCLUSION: Our results provide limited evidence that healthy eating patterns contribute to enhanced immune function and reduced inflammation in overweight and obese postmenopausal women.

Factors affecting urinary myoglobin stability in vitro.

Urine myoglobin concentrations are measured clinically to assess rhabdomyolysis and the related risk of renal damage. We studied urine myoglobin concentrations in vitro to explore the factors affecting stability. Myoglobin was very unstable in urine specimens, especially below pH 6.5, and its immunoreactivity deteriorated rapidly with increasing temperatures. The deterioration rate was influenced greatly by urine myoglobin concentration, suggesting rate-limiting kinetics. Myoglobin in acidic phosphate-buffered saline was significantly more stable than in acidic urine, indicating that urinary factors in addition to pH are involved in myoglobin instability. These unidentified urinary factors had a molecular weight of less than 10 kd. Our results provide additional insight into the mechanism involved in the instability of the urine myoglobin concentration. Understanding the stability of myoglobin in the preanalytic in vitro phase and its potential in vivo instability is essential in assuring the reliability and clinical usefulness of urine myoglobin measurements.

Quick parathormone assay in the surgical management of hyperparathyroidism.

BACKGROUND: Among the various new technologies in the field of parathyroid surgery is intraoperative quick parathormone measurements. OBJECTIVES: To evaluate the contribution of QPTH measurements during parathyroidectomy to the achievement of higher success rates. METHODS: QPTH assay using Immulite Turbo Intact PTH was measured in 32 patients undergoing parathyroidectomy: 30 for primary and 2 for secondary hyperparathyroidism. QPTH levels were measured at time 0 minutes (before incision) and at 10, 20, and 30 minutes after excision of the hyperfunctioning gland. Only a drop of 60% or more from the 0' level was considered to be a positive result. RESULTS: The mean QPTH level at time 0' for PHPT patients was 38.12 +/- 25.15 pmol/L (range 9.1-118 pmol/L). At 10 minutes post-excision of the hyperfunctioning gland (or glands), QPTH dropped by a mean of 73.80% to 9.89 +/- 18.78 pmol/L. CONCLUSIONS: Intraoperative QPTH level measurement is helpful in parathyroid surgery. A drop of 60% or more from 0' level indicates a successful procedure, and further exploration should be avoided.

Cyclic changes of plasma spermine concentrations in women.

Based on previous studies which suggest that blood polyamines fluctuate during the menstrual cycle, the present study was set to determine whether plasma concentrations of the polyamine spermine show menstrual cycle-associated changes and if so, how these changes relate to phasic variations in other female hormones. Blood samples were collected from a group of 9 healthy women of various ages at 5 defined periods during their menstrual cycle including 1 woman on oral contraceptives. Spermine concentrations were determined in plasma acid extracts by reversed-phase high performance liquid chromatography method. Plasma estradiol, LH and FSH were measured by microparticle enzyme immunoassay using an automatic analyzer. Spermine concentrations, 104.4 +/- 12.2 nmol/ml at 1-3 day of the cycle, were increased transiently with a peak (263.8 +/- 22.1 nmol/ml) at 8-10 day and declined to 85.4 +/- 29.8 nmol/ml by 21-23 day of the cycle. The peak spermine concentrations coincided with the first increase in plasma estrogen levels. The individual variations in the temporal profile of spermine concentrations were of similar magnitude as individual differences in other female hormones. We conclude that: a) Plasma spermine concentrations undergo distinct cyclic alterations during the menstrual cycle with peak concentrations coinciding with the first estradiol increase, and b) Peak plasma spermine concentrations occur during the follicular phase, just prior to ovulation, during the period of rapid endometrial growth.