Total Exposure (total + exposure)

Distribution by Scientific Domains


Selected Abstracts


A register study of the impact of stopping third trimester selective serotonin reuptake inhibitor exposure on neonatal health

ACTA PSYCHIATRICA SCANDINAVICA, Issue 6 2010
W. Warburton
Warburton W, Hertzman C, Oberlander TF. A register study of the impact of stopping third trimester selective serotonin reuptake inhibitor exposure on neonatal health. Objective:, To determine whether risk for adverse neonatal outcomes are reduced by stopping SSRI use before the end of pregnancy. Method:, Using population health data, maternal health and prenatal SSRI prescriptions were linked to neonatal birth records (N = 119 547) (1998,2001). Neonates SSRI-exposed in the last 14 days (L14) of gestation were compared with infants who had gestational exposure, but not during the last 14 days (NL14). Propensity score matching was used to control for potential confounders (total exposure, maternal health characteristics). Results:, Increased risk for neonatal respiratory distress was present where L14 exposure occurred compared with risk where exposure stopped before L14. However, controlling for potential maternal and neonatal confounders, differences disappeared. Conclusion:, Controlling for maternal illness severity, reducing exposure to SSRI's at the end of pregnancy had no significant clinical effect on improving neonatal health. These findings raise the possibility that some adverse neonatal outcomes may not be an acute pharmacological condition such as toxicity or withdrawal. [source]


Timing of exposure to a pulp and paper effluent influences the manifestation of reproductive effects in rainbow trout

ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 11 2002
Michael R. Van den Heuvel
Abstract Rainbow trout were exposed to a secondary treated, thermomechanical/bleached kraft pulp and paper effluent in 12,000-L, flow-through exposure tanks at an environmental research facility located at a pulp and paper mill in Kawerau, New Zealand. Trout (age, 2+ years) were obtained from a local hatchery and exposed either to upstream river water or a nominal concentration of 12% (v/v) effluent diluted in upstream river water. Three treatment groups were used: Effluent exposure that started approximately three months before gonadal growth (eight-month total exposure), effluent exposure that started approximately halfway through gonadal development (two-month total exposure), and trout exposed to reference water alone for the total duration of the experiment. Trout were sacrificed just before spawning; exposure, growth, and reproductive endpoints were assessed during and at the termination of the experiment. Reduction in growth was observed in both sexes in the eight-month treatment group relative to the river water reference treatment group. No differences were observed in condition factor or liver size in either treatment. Females in the eightmonth exposure group also had significantly lower ovary weight. The two-month exposure group showed no differences from the reference group in growth or somatic indices. Estradiol and testosterone were reduced in blood samples taken from the eight-month exposure group by four months into the experiment as compared to the reference treatment. Steroid and vitellogenin levels in individual female trout from this treatment were significantly correlated with gonadosomatic indices (GSI) measured at the termination of the experiment. The GSI was not correlated strongly or consistently with pregnenolone, nor were any treatment-related pregnenolone differences observed, indicating that the steroid hormone reductions likely were not related to cholesterol side-chain cleavage. Male trout showed significant induction of vitellogenin and lower 11-ketotestosterone during the experiment (only the eight-month group was examined), but this did not result in any significant differences in testes development. Thus, this study has shown an impact of pulp mill effluent exposure on the reproductive physiology of female trout that appeared to be hormonally mediated. Furthermore, the effect could only be manifest when the exposure was initiated before the start of gonad development. [source]


PRECLINICAL STUDY: Disposition of ,9 tetrahydrocannabinol in CF1 mice deficient in mdr1a P-glycoprotein

ADDICTION BIOLOGY, Issue 3-4 2008
Laurence Bonhomme-Faivre
ABSTRACT P-glycoprotein (P-gp) plays a major role in drug efflux. All the transported substrates are more or less hydrophobic and amphiphatic in nature. Being lipophilic, ,9 tetrahydrocannabinol (THC), the main cannabis component, could be a potential P-gp substrate. The aim of this project was to determine the contribution of the mdr1a gene product to THC disposition. Therefore, oral THC and digoxin (substrate test for P-gp) pharmacokinetics have been investigated in the intestinal epithelium and in the brain capillary endothelium of CF1 mdr1a (,/,) mice (mice naturally deficient in P-gp). These pharmacokinetics were compared to THC and digoxin oral pharmacokinetics in wild type mice mdr1a (+/+) (not P-gp deficient). The application of Bailer's method showed that THC total exposure measured by the area under the plasma concentration time curve was 2.17-fold higher in CF1 mice naturally deficient in P-gp than in wild type mice after oral administration of 25 mg/kg of THC, and 2.4-fold higher after oral administration of 33 µg/kg of digoxin. As a consequence, the oral bioavailability of THC and digoxin was higher in naturally P-gp-deficient mice. We concluded that P-gp limits THC oral uptake and mediates direct drug excretion from the systemic circulation into the intestinal lumen. [source]


Stress, Religious Coping Resources, and Depressive Symptoms in an Urban Adolescent Sample

JOURNAL FOR THE SCIENTIFIC STUDY OF RELIGION, Issue 1 2008
RUSSELL A. CARLETON
We surveyed low-income urban adolescents about their total exposure to urban stressors and their use of religious coping resources, specifically in the areas of social support, spiritual support, and community service opportunities provided by their congregations. Additionally, we assessed their current levels of depressive symptomatology. Among females, the relationship between stress and depressive symptoms was moderated by the use of spiritual support and community service opportunities. The moderating relationship was such that at low levels of stress, high usage of these resources protected against the development of depressive symptoms. At high levels of stress, however, the protective relationship was lost. Lastly, when the social support aspects of religious coping were statistically controlled, the moderation effect disappeared, suggesting that within this sample, the social support seeking aspects of the resources, rather than their religious nature, was responsible for the effects. [source]


Emergency hospital admissions in idiopathic Parkinson's disease

MOVEMENT DISORDERS, Issue 9 2005
Henry Woodford BSc
Abstract Little is known about the hospital inpatient care of patients with idiopathic Parkinson's disease (PD). Here, we describe the features of the emergency hospital admissions of a geographically defined population of PD patients over a 4-year period. Patients with PD were identified from a database for a Parkinson's disease service in a district general hospital with a drainage population of approximately 180,000. All admissions of this patient subgroup to local hospitals were found from the computer administration system. Two clinicians experienced in both general medicine and PD then reviewed the notes to identify reasons for admission. Admission sources and discharge destinations were recorded. Data regarding non-PD patients was compared to PD patients on the same elderly care ward over the same time period. The total number of patients exposed to analysis was 367. There was a total exposure of 775.8 years and a mean duration of 2.11 years per patient. There were 246 emergency admissions to the hospital with a total duration of stay of 4,257 days (mean, 17.3 days). These days were accounted for by 129 patients (mean age, 78 years; 48% male). PD was first diagnosed during 12 (4.9%) of the admissions. The most common reasons for admission were as follows: falls (n = 44, 14%), pneumonia (n = 37, 11%), urinary tract infection (n = 28, 9%), reduced mobility (n = 27, 8%), psychiatric (n = 26, 8%), angina (n = 21, 6%), heart failure (n = 20, 6%), fracture (n = 14, 4%), orthostatic hypotension (n = 13, 4%), surgical (n = 13, 4%), upper gastrointestinal bleed (n = 10, 3%), stroke/transient ischemic attack (n = 8, 2%), and myocardial infarction (n = 7, 2%). The mean length of stay for the PD patients on the care of elderly ward specializing in PD care was 21.3 days compared to 17.8 days for non-PD patients. After hospital admission, there was a reduction in those who returned to their own home from 179 to 163 and there was an increase in those requiring nursing home care from 37 to 52. Infections, cardiovascular diseases, falls, reduced mobility, and psychiatric complications accounted for the majority of admissions. By better understanding the way people with PD use hospital services, we may improve quality of care and perhaps prevent some inpatient stays and care-home placements. © 2005 Movement Disorder Society [source]


UV Exposure of Elementary School Children in Five Japanese Cities,

PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 2 2005
Masaji Ono
ABSTRACT A 1 week UV-exposure measurement and outdoor-activity pattern survey was conducted for elementary school children for four seasons at five sites in Japan, i.e. Sapporo (43°05,N, altitude 40 m), Tsukuba (36°05,N, 20 m), Tokyo (35°40,N, 45 m), Miyazaki (31°60,N, 40 m) and Naha (26°10,N, 5 m), and UV exposure was measured directly and estimated using outdoor-activity records. The study site with largest UV exposure was Miyazaki, a southern rural area. Comparing the results for boys and girls, UV exposure was larger in boys. UV exposure was large in spring and summer and small in winter. The total amount of UV exposure in spring and summer contributed 57.7,73.4% of total exposure for the year. As a whole, 8.1% and 1.8% of the schoolchildren were exposed to more than 1 minimum erythemal dose (MED) and 2 MED of solar UV in a day, respectively. The estimated yearly UV exposure ranged from 49 207 J/m2 in Miyazaki to 31 520 J/m2 in Tsukuba. The actual UV exposure correlated to potential UV exposure, estimated using outdoor-activity records and ambient UV irradiance, but the ratio differed by season and site. The yearly average of percent UV exposure to ambient UV on a horizontal plane ranged from 9.9% in Tokyo to 4.0% in Naha. In the questionnaire survey on outdoor-activity pattern, a short question "How long did you spend time outdoors between 0900 and 1500 h?" gives the best estimates of UV exposure. [source]


Possible health impact of phytoestrogens and xenoestrogens in food,

APMIS, Issue 3 2001
Dolores Ibarreta
Plants produce estrogen-like substances, denominated phytoestrogens, which are present in many human foodstuffs. The consumption of phytoestrogens has been associated with a variety of protective effects. Their relative estrogenic potency combined with their concentrations in food and human plasma indicate biological relevance. However, their biological properties differ from those of estradiol or other endogenous estrogens in humans. For instance, their possible effects on SHBG, inhibition of steroid metabolizing enzymes, anti-proliferative and anti-angiogenetic and other side effects have been described. Furthermore, phytoestrogens can exert estrogenic and antiestrogenic activities at the same time and their potency and metabolism have not been yet elucidated in all cases. In recent decades growing evidence has accumulated on the hormone-like effects of synthetic chemicals that appeared in the environment. The possible impact of xenoestrogens, to which humans are also exposed through the food chain, needs to be further clarified as well. The molecular effects and control mechanisms of these substances, their pharmacokinetics, threshold levels and dose-response differences are issues that require further research before a full assessment of their effect on humans can be drawn. Evaluating the total exposure and impact of this estrogenic effect is very challenging because of the lack of specific knowledge in some areas and the differences in the biological activity among these substances, as pinpointed in this review. [source]


Radiofrequency exposure on fast patrol boats in the Royal Norwegian Navy,an approach to a dose assessment

BIOELECTROMAGNETICS, Issue 5 2010
Valborg Baste
Abstract Epidemiological studies related to radiofrequency (RF) electromagnetic fields (EMF) have mainly used crude proxies for exposure, such as job titles, distance to, or use of different equipment emitting RF EMF. The Royal Norwegian Navy (RNoN) has measured RF field emitted from high-frequency antennas and radars on several spots where the crew would most likely be located aboard fast patrol boats (FPB). These boats are small, with short distance between the crew and the equipment emitting RF field. We have described the measured RF exposure aboard FPB and suggested different methods for calculations of total exposure and annual dose. Linear and spatial average in addition to percentage of ICNIRP and squared deviation of ICNIRP has been used. The methods will form the basis of a job exposure matrix where relative differences in exposure between groups of crew members can be used in further epidemiological studies of reproductive health. Bioelectromagnetics 31:350,360, 2010. © 2010 Wiley-Liss, Inc. [source]


Beryllium sensitivity among workers at a Norwegian aluminum smelter,

AMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 7 2010
A.M. Nilsen PhD
Abstract Background Sensitivity to beryllium was investigated among workers at an aluminum smelter in Norway as a consequence of the findings in an occupational exposure survey. Methods Three hundred and sixty-two employees and 31 reference persons were tested for sensitization to beryllium with the beryllium lymphocyte proliferation test (BeLPT) based on specifications by the US Department of Energy in 2001. The results are reported as abnormal, borderline, or normal. Results One person (0.28%) from the aluminum smelter was found to have abnormal results in two separate blood samples and is sensitized to beryllium. Three other persons had one abnormal test that was not confirmed by a second test. One person in the reference group had one abnormal and one normal test result. No borderline samples were detected. None of the employees with one or more abnormal sample results had pot room asthma. The sensitized individual worked in a Soederberg line in 1972,1974. The beryllium concentration in the work atmosphere is estimated to have been similar as today (0.1,0.3,µg/m3), but work routines, etc. would cause higher total exposures. Conclusions Only one sensitized person of 362 is in line with what is found in other studies in the aluminum industry. The low number, compared with the beryllium handling industry, may be attributable to lower work atmosphere concentrations, beryllium speciation effects, or use of respiratory protection equipment. Pot room asthma does not appear to be associated with beryllium sensitization. Am. J. Ind. Med. 53:724,732, 2010. © 2010 Wiley-Liss, Inc. [source]