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PubMed2006

A randomized, placebo-controlled trial of sertraline in the treatment of night eating syndrome.

OBJECTIVE: The authors assessed the efficacy of sertraline in the treatment of night eating syndrome. METHOD: Thirty-four outpatients diagnosed with night eating syndrome were randomly assigned to receive either sertraline (N=17) or placebo (N=17) in an 8-week, double-blind, flexible-dose (50-200 mg/day) study. A mixed effects linear regression model was used to analyze change in the primary outcome measure, Clinical Global Impression (CGI) improvement rating. Secondary outcomes included changes in night eating symptoms, the number of nocturnal awakenings and ingestions, total daily caloric intake after the evening meal, CGI severity ratings, quality of life ratings, and weight. RESULTS: Sertraline was associated with significantly greater improvement than placebo. Twelve subjects in the sertraline group (71%) were classified as having responded (CGI improvement rating < or = 2, indicating much or very much improved) versus only three (18%) in the placebo group. There were also significant improvements in night eating symptoms, CGI severity ratings, quality of life ratings, frequency of nocturnal ingestions and awakenings, and caloric intake after the evening meal. Overweight and obese subjects in the sertraline group (N=14) lost a significant amount of weight by week 8 (mean=-2.9 kg, SD=3.8) compared with overweight and obese subjects receiving placebo (N=14) (mean=-0.3 kg, SD=2.7). CONCLUSIONS: In this 8-week trial, sertraline was effective in the treatment of night eating syndrome and was well tolerated.

Adult↗

PubMed2006

Multicenter investigation of the opioid antagonist nalmefene in the treatment of pathological gambling.

OBJECTIVE: Pathological gambling is a disabling disorder experienced by approximately 1%-2% of adults and for which there are few empirically validated treatments. The authors examined the efficacy and tolerability of the opioid antagonist nalmefene in the treatment of adults with pathological gambling. METHOD: A 16-week, randomized, dose-ranging, double-blind, placebo-controlled trial was conducted at 15 outpatient treatment centers across the United States between March 2002 and April 2003. Two hundred seven persons with DSM-IV pathological gambling were randomly assigned to receive nalmefene (25 mg/day, 50 mg/day, or 100 mg/day) or placebo. Scores on the primary outcome measure (Yale-Brown Obsessive Compulsive Scale Modified for Pathological Gambling) were analyzed by using a linear mixed-effects model. RESULTS: Estimated regression coefficients showed that the 25 mg/day and 50 mg/day nalmefene groups had significantly different scores on the Yale-Brown Obsessive Compulsive Scale Modified for Pathological Gambling, compared to the placebo group. A total of 59.2% of the subjects who received 25 mg/day of nalmefene were rated as "much improved" or "very much improved" at the last evaluation, compared to 34.0% of those who received placebo. Adverse experiences included nausea, dizziness, and insomnia. CONCLUSIONS: Subjects who received nalmefene had a statistically significant reduction in severity of pathological gambling. Low-dose nalmefene (25 mg/day) appeared efficacious and was associated with few adverse events. Higher doses (50 mg/day and 100 mg/day) resulted in intolerable side effects.

Adult↗

PubMed2026

Changes in ACL T2* Metrics Over the Course of the Female Menstrual Cycle: A New Biomarker for the ACL Injury Risk?

BACKGROUND: Sex-based disparities in the anterior cruciate ligament (ACL) injury risk may be partly explained by cyclic variations in sex hormones that drive systemic shifts in tissue osmoregulation. Ultrashort echo time (UTE) T2* magnetic resonance imaging provides a noninvasive, quantitative means of evaluating the water content and collagen orientation in tissue. HYPOTHESIS: Eumenorrheic female participants will exhibit significant ACL T2* changes across the cycle, while anovulatory control participants will demonstrate no significant changes over time. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: A total of 25 women with no prior knee injuries were enrolled: 10 premenopausal, eumenorrheic participants and 15 anovulatory control participants (6 postmenopausal and 9 premenopausal using oral contraceptives). Bilateral knee magnetic resonance imaging was performed at 4 time points evenly spaced over 1 month, with the first visit within 24 hours of menses onset. Ovulation status was confirmed using commercially available ovulation predictor kits. Three-dimensional UTE sequences (11 echoes; 0.03-25 ms) were acquired to evaluate bicomponent ACL T2* metrics. Linear mixed-effects models assessed temporal differences in long and short T2* values, and the Cohen d quantified effect size. RESULTS: Eumenorrheic participants demonstrated significantly shorter preovulatory long T2* values compared with postovulatory values (mean difference, 1.0 ms [95% CI, 0.2-1.9 ms]; P = .015; Cohen d = 0.51). No significant temporal differences were observed for any T2* metric in anovulatory controls. CONCLUSION: Eumenorrheic female participants exhibited significant preovulatory to postovulatory changes in ACL T2* metrics, while anovulatory controls demonstrated no significant changes over time. These findings suggest that ACL T2* metrics are sensitive to cyclic fluctuations in female sex hormones across the menstrual cycle.

Humans↗

PubMed2006

Investigation of 3 industry-wide applied storage conditions for compound libraries.

The appropriate storage conditions for a compound file are a crucial factor for the success of drug discovery projects. In this study, 778 highly diverse compounds dissolved in 100% DMSO were stored under 3 industry-wide accepted storage conditions, and the compound integrity was monitored for a period of 6 months. The storage conditions selected were (1) under argon at +15 degrees C, (2) under argon at -20 degrees C, and (3) under ambient atmosphere at -20 degrees C. Each sample was assessed every 4 weeks by liquid chromatography coupled to mass spectrometry (LC/MS). Based on the resulting experimental data, a statistical projection of compound integrity over a period of 4 years for each of the 3 storage conditions was generated applying a linear mixed-effects model. A moderate loss of compound integrity of 12% was calculated for storage at -20 degrees C under argon, a loss of 21% for storage at -20 degrees C under ambient atmosphere, and a strong decrease of 58% for storage at +15 degrees C under argon over this period. The initial purity of the compounds does also influence the rate of compound degradation. Compounds with an initial purity of 50% to 75% degraded faster than compounds with an initial purity of more than 75%. The results of the study enable the prediction of the point in time, when the purity of a compound population falls below a predefined threshold that would trigger the resolubilization or retirement of the compound population represented by the analyzed samples.

Confidence Intervals↗

PubMed2026

Extreme Temperature and Incident Diabetes Risk Among Middle-Aged and Older Adults in China: A National Longitudinal Cohort Study.

BACKGROUND AND AIMS: The metabolic consequences of extreme temperature exposure in nondiabetic populations remain poorly understood. This study aimed to examine associations between heatwave and coldwave exposure and incident diabetes mellitus (DM) and impaired glucose tolerance (IGT) in middle-aged and older Chinese adults. METHODS: A total of 1803 China Health and Retirement Longitudinal Study participants aged ≥45 years with normoglycemia at baseline were followed from Wave 1 (2011) to Wave 3 (2015). Eighteen extreme-temperature indicators were derived from city-level fifth-generation European Centre for Medium-Range Weather Forecasts atmospheric reanalysis data. Outcomes were classified according to American Diabetes Association criteria. Generalized linear mixed-effects models (GLMMs) were pooled across five imputed datasets, with Bonferroni correction for multiple comparisons (α = 0.0028) and sensitivity analysis adjusting for individual follow-up duration. RESULTS: All nine heatwave indicators showed odds ratios (ORs) < 1.0 for DM and IGT. HT9 (≥97.5th percentile, ≥4 consecutive days) was the sole Bonferroni-significant result: OR = 0.845 (95% confidence interval [CI]: 0.802-0.890). Coldwave indicators showed no consistent associations. Age significantly modified the HT9 effect (P-interaction = 0.004): adults aged 65-84 showed a stronger inverse association (OR = 0.616) than those aged < 65 (OR = 0.921). CONCLUSION: Prolonged heatwave exposure was consistently associated with reduced diabetes risk, with pronounced age heterogeneity. Replication in larger prospective studies is warranted.

Humans↗

PubMed2026

Large-scale proteomics profiling of peripheral blood of DM1 patients identifies biomarkers for disease severity and functional capacity.

BackgroundMyotonic Dystrophy Type 1 (DM1), the most common genetic neuromuscular disorder in adults, poses significant challenges for drug development due to its multisystem nature and high clinical variability in symptoms and disease progression. With a growing number of therapies entering clinical trials, this study addresses the urgent need for biomarkers that can serve as surrogate endpoints.MethodsWe profiled 437 serum samples from adult DM1 patients collected at two timepoints of the OPTIMISTIC trial using bottom-up mass spectrometry with data-independent acquisition. Associations between protein expression, the disease-causing CTG-repeat and 25 clinical outcome measures were studied using linear mixed-effect models. All key study findings were validated in an independent cohort of 69 DM1 patients and 10 healthy controls.ResultsOf the 259 identified proteins, 161 showed significant associations with the CTG-repeat length (FDR < 5%). Hypogammaglobulinemia was confirmed and shown to be worse in severely affected patients. A strong proteomic signature was associated with clinical measures of functional capacity, with the 6-Minute Walk Test showing the strongest signal (70 associations, FDR < 5%). These novel associations reveal a compelling link between chronic inflammation and reduced functional capacity. A machine learning algorithm identified a minimal set of 13 proteins robustly reflecting both the underlying genetic defect and functional capacity.ConclusionsDM1 induces a broad disease fingerprint in the serum proteome, predominantly affecting proteins of the immune system. A carefully selected panel of proteins showed the greatest potential to meet the statistical criteria required for surrogate endpoints in clinical trials.

Humans↗

PubMed2005

Effect of individual psychological intervention in Chinese women with gynecologic malignancy: a randomized controlled trial.

PURPOSE: To evaluate the effectiveness of psychological intervention in the care of cancer patients and to determine whether routine use of individual psychological therapies is indicated. PATIENTS AND METHODS: Patients with newly diagnosed gynecologic malignancies from August 1999 to November 2000 were recruited and randomly assigned to either a control group receiving routine medical care or to an intervention group receiving individual psychotherapy. A set of fixed-choice, self-report questionnaires assessing the patients' psychological status, quality of life, and their perceptions related to the medical consultations was completed at recruitment and then every 3 months for 18 months. Data analysis was performed according to the intention-to-treat principle by fitting the data into a linear mixed-effects model. Multivariable analyses were performed to examine the effects of confounding factors. RESULTS: One hundred fifty-five patients participated in the trial. There were no statistically significant differences between the two groups at baseline. There was a trend toward better quality of life and functional status and also improvement of the symptoms over time for both groups. No differences were found between the groups in the scores measured by any of the instruments at baseline and at any time points after the cancer diagnosis. Psychological intervention had no significant effects on the psychosocial parameters. CONCLUSION: Routine use of psychological therapies as given in our format has no significant effect on the patients' quality of life and psychological status.

Activities of Daily Living↗

PubMed1994

Hyperglycemia-induced hyperinsulinemia decreases maternal and fetal plasma protein C concentration during ovine gestation.

To determine effects of diabetic gestation on plasma concentration of the coagulation regulatory protein, protein C, pregnant ewes were given glucose infusions to raise plasma glucose to twice baseline concentration or insulin infusions to lower glucose concentration to half baseline value. Control animals received no infusions. Concentrations of protein S, factor X, and antithrombin III were determined for comparison. Concentrations of glucose, insulin, and those above were determined thrice weekly for 2-9 wk. Short-term (8-12 h) infusions of glucose or insulin were performed to isolate their effect on concentration of protein C. Results were analyzed using a two-tailed t test, and protein C concentrations were further analyzed using a full linear mixed-effects model. In long-term infusions, hyperglycemia-induced hyperinsulinemia (mean insulin concentration 141 microU/L) exerted negative effects on maternal concentrations of protein C [0.69 U/mL, n (number of samples) = 32, experimental versus 0.97 U/mL, n = 157, control], protein S (0.86 U/mL, n = 31, experimental versus 1.04 U/mL, n = 109, control), and factor X (0.89 U/mL, n = 31, experimental versus 1.04 U/mL, n = 109, control); it exerted no effects on antithrombin III (1.05 U/mL, n = 23, experimental versus 1.04 U/mL, n = 32, control). The fetal lamb did not respond to chronic moderate hyperglycemia (mean 33 mg/dL) with a consistent change in insulin concentration (mean 10 versus 9 microU/mL): no coagulation protein changed.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed2026

Prevalence of Slowly Expanding Lesions in Patients With Multiple Sclerosis: A Systematic Review and Meta-Analysis.

BACKGROUND AND OBJECTIVES: Chronic active lesions (CALs) reflect chronic inflammation in multiple sclerosis (MS). Slowly expanding lesions (SELs) are CALs identified on conventional MRI by linear, concentric expansion over time, while paramagnetic rim lesions (PRLs) are CALs characterized by a paramagnetic rim on susceptibility-sensitive MRI. However, the prevalence of SELs and their overlap with PRLs remain unclear. The aims of this study were to (1) estimate the proportion of SELs among all T2 lesions and the proportion of patients with at least 1 SEL and (2) assess the proportion of SELs overlapping with PRLs. METHODS: We systematically searched PubMed, Scopus, Web of Science, and Embase on February 1, 2026, for studies evaluating SELs in MS. At least 2 authors independently assessed study eligibility. Primary outcomes were the pooled proportion of SELs among T2 lesions and the proportion of patients with at least 1 SEL. We estimated mean per-patient volumes of SELs and total T2 lesions and the proportion of SELs overlapping with PRLs. Random-effects generalized linear mixed-effects models and inverse-variance methods were used, with between-study heterogeneity assessed using τ2 and I2 and robustness using sensitivity analyses. Univariable meta-regression explored heterogeneity. PROSPERO: CRD42024603778. RESULTS: Of 5,980 records, 20 studies comprising 4,786 patients with MS were included (mean age: 43.6 ± 6.3 years; 63.7% female). Sample sizes varied by outcome. SELs accounted for 14% (95% CI 10-21) of all T2 lesions, and 78% (67-85) of patients had at least 1 SEL. After sensitivity analysis, per-patient mean volumes were 1.42 mL (0.79-2.06) for SELs and 10.6 mL (8.53-12.67) for total T2 lesions. In total, 11% (6-20) of SELs overlapped with PRLs. In subgroup analyses, proportions of SELs were similar in relapsing-remitting and progressive MS (15%), but the proportion of patients with at least 1 SEL was higher in progressive MS. Between-study heterogeneity was high across analyses with no significant sources identified. DISCUSSION: Although SELs represent a minority of T2 lesions, most patients have at least 1 SEL and a subset overlaps with PRLs, suggesting a partial correspondence between these 2 imaging markers of chronic inflammatory activity. Limitations include possible publication bias, high unexplained heterogeneity, differences in SEL identification methods, and differences in MRI time point number/timing.

Humans↗

PubMed1997

Cognitive, behavioral, and motor effects of the NMDA antagonist ketamine in Huntington's disease.

BACKGROUND: Excitotoxicity may contribute to neuronal degeneration in Huntington's disease (HD). N-methyl-D-aspartate (NMDA) receptor antagonists can prevent neuronal degeneration caused by excitotoxicity, but their effects in HD patients are not known. METHODS: We investigated the acute cognitive, behavioral, and motor effects of the NMDA-receptor antagonist ketamine in HD patients. Double-blind infusions of 0.10, 0.40, and 0.60 mg/kg/hr ketamine were given to 10 HD patients on one test day and compared with placebo infusions on a second, identical testing day. Linear mixed-effects models and randomization tests were used to identify whether, and at which dose, a significant change from baseline occurred in outcome variables. RESULTS: We demonstrated that ketamine is well tolerated at low and intermediate subanesthetic doses. Intermediate ketamine doses produced specific decline in memory and verbal fluency. Higher subanesthetic doses caused a significant increase in psychiatric symptoms and impairment of eye movements. CONCLUSIONS: These results describe the spectrum of clinical effects produced by increasing NMDA receptor blockade in HD patients. The clinical effects appearing with higher levels of NMDA receptor blockade can identify the range of doses used in clinical trials of NMDA receptor antagonists.

Adult↗

PubMed2001

Evidence for familial aggregation of tremor in normal individuals.

BACKGROUND: Tremor occurs in most normal individuals, and this tremor may offer basic clues about the mechanisms of neuromuscular control. It is not known whether genetic factors influence the magnitude of tremor in normal families. OBJECTIVE: To assess the familial aggregation of tremor in normal families. METHODS: Control subjects from the Washington Heights-Inwood community in northern Manhattan, NY, were enrolled in a family study. These subjects and their first- and second-degree relatives underwent a videotaped tremor examination. Two neurologists rated the severity of tremor on the videotaped examination, assigning a total tremor score (0 to 36 [maximum]). Associations between the control subjects' and their relatives' total tremor scores were assessed using correlation coefficients and linear regression analysis. In addition, maximum likelihood methods were used to fit a linear mixed-effects model to the total tremor scores of probands and their siblings, after excluding any relatives with essential tremor. RESULTS: There were 56 control subjects and 226 relatives. Tremor was clinically detectable in 221 (97.8%) of 226 relatives. There was an association between the control subjects' total tremor scores and those of their siblings (r = 0.40; p = 0.018), those of all of their first-degree relatives (siblings and children combined, r = 0.20; p = 0.037), but not those of their second-degree relatives (r = 0.002; p = 0.99). In analyses of probands and normal siblings, the estimate of the variance of the family-specific component of the age-adjusted total tremor score was different from zero (p < 0.005), and the family specific component was estimated to account for 52% of the variability in the scores. CONCLUSIONS: Tremor aggregates in normal families, suggesting that genetic factors may contribute to its etiology. Other studies might be designed by investigators to identify these genes through genetic linkage or association analysis. Identification of such genes would help to elucidate the mechanisms underlying this ubiquitous condition.

Adult↗

PubMed1995

Variability and tracking of physical activity over 2 yr in young children.

The purpose of this study was to examine tracking of physical activity at home and recess in young children. Three hundred fifty-one Mexican-American and Anglo-American children entered the study (mean age = 4.4 yr), and 83% completed 2 yr of measurement. Physical activity was directly observed on 10 d over 2 yr. Measurement waves occurred every 6 months, and each wave consisted of 2 d of observation within 1 wk. Children were observed for 60 min at home on a weekday evening and up to 30 min during recess at preschool or school. Maximum likelihood procedures using a linear mixed-effects model indicated that most of the variance in home and recess physical activity was accounted for by short-term/weekly factors. Tracking of physical activity accounted for 15% of the total variance at home and 8% at recess. Pearson correlations for physical activity over time were higher at home than at recess. Tracking of home physical activity was r = 0.15 when single days were correlated and r = 0.36 when the means of 4 d were correlated. There was a small, but detectable, stable component of physical activity in young children, at least at home.

Child Behavior↗

PubMed2004

Five-year immunological outcome of highly active antiretroviral treatment in a clinical setting: results from a single HIV treatment centre.

Our objective was to study the evolution of CD4 cell count five years after starting highly active antiretroviral treatment (HAART) in a clinical setting. The study was performed at the HIV outpatient clinic, Institute of Tropical Medicine, Antwerp. All patients (n = 225) who started HAART in 1997, who had a CD4 cell count within six months prior to starting HAART and who were subsequently followed for at least two years were included. Change in CD4 cell count after start of HAART and the influence of patient and clinical factors were investigated using graphical exploration, endpoint analysis and mixed-effects linear regression. The mean CD4 cell count at start of HAART was 280 cells/mm(3). At the five-year endpoint of the study the mean increase in CD4 cell count was 333 cells/mm(3), while 79% of the patients had a viral load less than 400 copies/mL. There was a significant negative correlation between increase in CD4 cell count at five years and time since first positive HIV test at start of HAART (P = 0.021). Patients who ever had a HAART interruption of more than seven days had a significantly lower increase in CD4 cell count than those who did not (225 cells/mm(3) compared with 438 cells/mm(3); P < 0.001). A mixed-effects linear regression model additionally suggested a significant impact of exposure to antiretrovirals prior to HAART (P = 0.03). Overall, the recovery of CD4 cell count after five years of HAART is good, although therapy interruptions have an important negative impact.

Adult↗

PubMed2003

Measurement of offline exhaled nitric oxide in a study of community exposure to air pollution.

As part of a large panel study in Seattle, Washington, we measured levels of exhaled nitric oxide (eNO) in children's homes and fixed-site particulate matter with aerodynamic diameters of 2.5 micro m or less (PM(2.5)) outside and inside the homes as well as personal PM(2.5) during winter and spring sessions of 2000-2001. Nineteen subjects 6-13 years of age participated; 9 of the 19 were on inhaled corticosteroid (ICS) therapy. Exhaled breath measurements were collected offline into a Mylar balloon for up to 10 consecutive days. Mean eNO values were 19.1 (SD +/- 11.4) ppb in winter sessions and 12.5 +/- 6.6 ppb in spring sessions. Fixed-site PM(2.5) mean concentrations were 10.1 +/- 5.7 microg/m(3) outside homes and 13.3 +/- 1.4 inside homes; the personal PM(2.5) mean was 13.4 +/- 3.2 microg/m(3). We used a linear mixed-effects model with random intercept and an interaction term for medications to test for within-subject-within-session associations between eNO and various PM(2.5) values. We found a 10 microg/m(3) increase in PM(2.5) from the outdoor, indoor, personal, and central-site measurements that was associated with increases in eNO in all subjects at lag day zero. The effect was 4.3 ppb [95% confidence interval (CI), 1.4-7.29] with the outdoor monitor, 4.2 ppb (95% CI, 1.02-7.4) for the indoor monitor, 4.5 ppb (95% CI, 1.02-7.9) with the personal monitor, and 3.8 ppb (95% CI, 1.2-6.4) for the central monitors. The interaction term for medication category (ICS users vs. nonusers) was significant in all analyses. These findings suggest that eNO can be used as an assessment tool in epidemiologic studies of health effects of air pollution.

Adolescent↗

PubMed2004

Personal exposure to submicrometer particles and heart rate variability in human subjects.

We conducted a study on two panels of human subjects--9 young adults and 10 elderly patients with lung function impairments--to evaluate whether submicrometer particulate air pollution was associated with heart rate variability (HRV). We measured these subjects' electrocardiography and personal exposure to number concentrations of submicrometer particles with a size range of 0.02-1 microm (NC0.02-1) continuously during daytime periods. We used linear mixed-effects models to estimate the relationship between NC0.02-1 and log10-transformed HRV, including standard deviation of all normal-to-normal intervals (SDNN), square root of the mean of the sum of the squares of differences between adjacent NN intervals (r-MSSD), low frequency (LF, 0.04-0.15 Hz), and high frequency (HF, 0.15-0.40 Hz), adjusted for age, sex, body mass index, tobacco exposure, and temperature. For the young panel, a 10,000-particle/cm3) increase in NC0.02-1 with 1-4 hr moving average exposure was associated with 0.68-1.35% decreases in SDNN, 1.85-2.58% decreases in r-MSSD, 1.32-1.61% decreases in LF, and 1.57-2.60% decreases in HF. For the elderly panel, a 10,000-particle/cm3 increase in NC0.02-1 with 1-3 hr moving average exposure was associated with 1.72-3.00% decreases in SDNN, 2.72-4.65% decreases in r-MSSD, 3.34-5.04% decreases in LF, and 3.61-5.61% decreases in HF. In conclusion, exposure to NC0.02-1 was associated with decreases in both time-domain and frequency-domain HRV indices in human subjects.

Adult↗

PubMed2005

Effects of ambient ozone exposure on mail carriers' peak expiratory flow rates.

The extent to which occupational exposure to ozone in ambient air can affect lung function remains unclear. We conducted a panel study in 43 mail carriers by measuring their peak expiratory flow rates (PEFRs) twice daily for 6 weeks in 2001. The daily exposure of each mail carrier to O3, particulate matter < 10 microm in aerodynamic diameter (PM10), and nitrogen dioxide was estimated by one air monitoring station in the center of the mail carrier's delivery area. Hourly concentrations of air pollutants during their exposure periods were 6-96 ppb for O3, 11-249 microg/m3 for PM10, and 14-92 ppb for NO2. Linear mixed-effects models were used to estimate the association between air pollution exposures and PEFR after adjusting for subject's sex, age, and disease status and for temperature and humidity. We found that night PEFR and the deviation in night PEFR were significantly decreased in association with 8-hr O3 exposures with a lag 0-2 days and by daily maximum O3 exposures with a lag of 0-1 day in our multipollutant models. By contrast, neither PM10 nor NO2 was associated with a PEFR reduction. Daily 8-hr mean concentrations of O3 had greater reduction effects on PEFR than did daily maximum concentrations. For a 10-ppb increase in the 8-hr average O3 concentration, the night PEFR was decreased by 0.54% for a 0-day lag, 0.69% for a 1-day lag, and 0.52% for a 2-day lag. We found that an acute lung function reduction occurs in mail carriers exposed to O3 concentrations below current ambient air quality standards and occupational exposure limits.

Adult↗

PubMed2005

Effects of particle size fractions on reducing heart rate variability in cardiac and hypertensive patients.

It is still unknown whether the associations between particulate matter (PM) and heart rate variability (HRV) differ by particle sizes with aerodynamic diameters between 0.3 microm and 1.0 microm (PM(0.3-1.0)), between 1.0 microm and 2.5 microm (PM(1.0-2.5)), and between 2.5 microm and 10 microm (PM(2.5-10)). We measured electrocardiographics and PM exposures in 10 patients with coronary heart disease and 16 patients with either prehypertension or hypertension. The outcome variables were standard deviation of all normal-to-normal (NN) intervals (SDNN), the square root of the mean of the sum of the squares of differences between adjacent NN intervals (r-MSSD), low frequency (LF; 0.04-0.15 Hz), high frequency (HF; 0.15-0.40 Hz), and LF:HF ratio for HRV. The pollution variables were mass concentrations of PM(0.3-1.0), PM(1.0-2.5), and PM(2.5-10). We used linear mixed-effects models to examine the association between PM exposures and log10-transformed HRV indices, adjusting for key personal and environmental attributes. We found that PM(0.3-1.0) exposures at 1- to 4-hr moving averages were associated with SDNN and r-MSSD in both cardiac and hypertensive patients. For an interquartile increase in PM(0.3-1.0), there were 1.49-4.88% decreases in SDNN and 2.73-8.25% decreases in r-MSSD. PM(0.3-1.0) exposures were also associated with decreases in LF and HF for hypertensive patients at 1- to 3-hr moving averages except for cardiac patients at moving averages of 2 or 3 hr. By contrast, we found that HRV was not associated with either PM(1.0-2.5) or PM(2.5-10). HRV reduction in susceptible population was associated with PM(0.3-1.0) but was not associated with either PM(1.0-2.5) or PM(2.5-10).

Aged↗

PubMed2006

Exposure to environmental ozone alters semen quality.

Idiopathic male infertility may be due to exposure to environmental toxicants that alter spermatogenesis or sperm function. We studied the relationship between air pollutant levels and semen quality over a 2-year period in Los Angeles, California, by analyzing repeated semen samples collected by sperm donors. Semen analysis data derived from 5,134 semen samples from a sperm donor bank were correlated with air pollutant levels (ozone, nitrogen dioxide, carbon monoxide, and particulate matter < 10 microm in aerodynamic diameter) measured 0-9, 10-14, and 70-90 days before semen collection dates in Los Angeles between January 1996 and December 1998. A linear mixed-effects model was used to model average sperm concentration and total motile sperm count for the donation from each subject. Changes were analyzed in relationship to biologically relevant time points during spermatogenesis, 0-9, 10-14, and 70-90 days before the day of semen collection. We estimated temperature and seasonality effects after adjusting for a base model, which included donor's date of birth and age at donation. Forty-eight donors from Los Angeles were included as subjects. Donors were included if they collected repeated semen samples over a 12-month period between January 1996 and December 1998. There was a significant negative correlation between ozone levels at 0-9, 10-14, and 70-90 days before donation and average sperm concentration, which was maintained after correction for donor's birth date, age at donation, temperature, and seasonality (p < 0.01). No other pollutant measures were significantly associated with sperm quality outcomes. Exposure to ambient ozone levels adversely affects semen quality.

Adult↗