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Biological Measures (biological + measure)
Selected AbstractsCD-sens: a biological measure of immunological changes stimulated by ASITALLERGY, Issue 5 2009A. Nopp Background:, Allergen-specific immunotherapy (ASIT) in allergic rhinitis and asthma is the only treatment that effects the long-term development of these diseases. Basophil allergen threshold sensitivity, CD-sens, which is a valuable complement to resource-demanding clinical challenge tests, was used to monitor the initiation of ASIT induced allergen ,blocking activity'. Methods:, Patients IgE-sensitized to timothy (n = 14) or birch (n = 19) pollen were started on conventional (8,16 weeks) or ultra rush ASIT, respectively, and followed by measurements of CD-sens, allergen binding activity (ABA) and serum IgG4- and IgE-antibody concentrations. Results:, CD-sens decreased during the early phase of ASIT-treatment. In parallel, ABA increased and correlated significantly with the increasing levels of IgG4 antibody concentrations. High dosages of allergen were more effective while mode of dosing up did not seem to matter. No change was seen in basophil reactivity. Conclusion:, CD-sens and ABA, in contrast to basophil reactivity, seem to be promising tools to monitor protective immune responses initiated by ASIT. [source] Brain cancer mortality and potential occupational exposure to lead: Findings from the National Longitudinal Mortality Study, 1979,1989INTERNATIONAL JOURNAL OF CANCER, Issue 5 2006Edwin van Wijngaarden Abstract We evaluated the association between potential occupational lead exposure and the risk of brain cancer mortality in the National Longitudinal Mortality Study (NLMS), which is a prospective census-based cohort study of mortality among the noninstitutionalized United States population (1979,1989). The present study was limited to individuals for whom occupation and industry were available (n = 317,968). Estimates of probability and intensity of lead exposure were assigned using a job-exposure matrix (JEM). Risk estimates for the impact of lead on brain cancer mortality were computed using standardized mortality ratio (SMR) and proportional hazards and Poisson regression techniques, adjusting for the effects of age, gender and several other covariates. Brain cancer mortality rates were greater among individuals in jobs potentially involving lead exposure as compared to those unexposed (age- and gender-adjusted hazard ratio (HR) = 1.5; 95% confidence interval (CI) = 0.9,2.3) with indications of an exposure,response trend (probability: low HR = 0.7 (95% CI = 0.2,2.2), medium HR = 1.4 (95% CI = 0.8,2.5), high HR = 2.2 (95% CI = 1.2,4.0); intensity: low HR = 1.2 (95% CI = 0.7,2.1), medium/high HR = 1.9 (95% CI = 1.0,3.4)). Brain cancer risk was greatest among individuals with the highest levels of probability and intensity (HR = 2.3; 95% CI = 1.3,4.2). These findings provide further support for an association between occupational lead exposure and brain cancer mortality, but need to be interpreted cautiously due to the consideration of brain cancer as one disease entity and the absence of biological measures of lead exposure. © 2006 Wiley-Liss, Inc. [source] Assessing river biotic condition at a continental scale: a European approach using functional metrics and fish assemblagesJOURNAL OF APPLIED ECOLOGY, Issue 1 2006D. PONT Summary 1The need for sensitive biological measures of aquatic ecosystem integrity applicable at large spatial scales has been highlighted by the implementation of the European Water Framework Directive. Using fish communities as indicators of habitat quality in rivers, we developed a multi-metric index to test our capacity to (i) correctly model a variety of metrics based on assemblage structure and functions, and (ii) discriminate between the effects of natural vs. human-induced environmental variability at a continental scale. 2Information was collected for 5252 sites distributed among 1843 European rivers. Data included variables on fish assemblage structure, local environmental variables, sampling strategy and a river basin classification based on native fish fauna similarities accounting for regional effects on local assemblage structure. Fifty-eight metrics reflecting different aspects of fish assemblage structure and function were selected from the available literature and tested for their potential to indicate habitat degradation. 3To quantify possible deviation from a ,reference condition' for any given site, we first established and validated statistical models describing metric responses to natural environmental variability in the absence of any significant human disturbance. We considered that the residual distributions of these models described the response range of each metric, whatever the natural environmental variability. After testing the sensitivity of these residuals to a gradient of human disturbance, we finally selected 10 metrics that were combined to obtain a European fish assemblage index. We demonstrated that (i) when considering only minimally disturbed sites the index remains invariant, regardless of environmental variability, and (ii) the index shows a significant negative linear response to a gradient of human disturbance. 4Synthesis and applications. In this reference condition modelling approach, by including a more complete description of environmental variability at both local and regional scales it was possible to develop a novel fish biotic index transferable between catchments at the European scale. The use of functional metrics based on biological attributes of species instead of metrics based on species themselves reduced the index sensitivity to the variability of fish fauna across different biogeographical areas. [source] Discrimination, psychosocial stress, and health among Latin American immigrants in OregonAMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 3 2010Heather H. McClure Chronic psychosocial stress related to discrimination has been shown to be associated with biological measures such as elevated systolic blood pressure (SBP), increased body fat, and higher fasting glucose levels. Few studies have examined these relationships in immigrant populations. The present study recruited a sample of 132 Oregon Latino immigrant adults to investigate the relationships between perceived discrimination and several health measures (blood pressure, body mass index [BMI], and fasting glucose). Results indicate that perceived discrimination stress predicted elevated SBP among men but not among women. Perceived discrimination was significantly higher among obese women than among women of normal BMI. The same pattern was not observed for men. Further, a strong trend relationship was detected: the higher women's reported discrimination stress, the higher their fasting glucose levels. Again, this pattern was not observed for men. These results suggest that chronic psychosocial stress plays an important role in disease risk among Latin American immigrants, and that male and female immigrants may have distinctive physiological responses. If confirmed, these findings may have important clinical and public health implications for chronic disease prevention among Latinos. Am. J. Hum. Biol., 2010. © 2009 Wiley-Liss, Inc. [source] Biomarkers of Mn exposure in humansAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 11 2007Donald Smith PhD Abstract Background Studies have reported associations between manganese (Mn) exposures and Mn levels in blood and urine, though the suitability of these biological measures as biomarkers of exposure is not well known. Methods We evaluated whether whole blood, plasma, and urine Mn levels reflect exposures in occupationally exposed humans. Results In active ferroalloy workers, blood Mn was associated with total air Mn levels in subjects currently exposed to low (median,=,0.42 ,g/m3, P,=,0.009) and moderate (median,=,4.2 ,g/m3, P,=,0.007) air Mn levels, but not in workers exposed to the highest Mn levels (median,=,292 ,g/m3, P,=,0.31). In bridge welders blood Mn (P,<,0.01), but not plasma or urine Mn was significantly associated with their cumulative respiratory exposure index. In welders, ,6% (range ,3,9%) of whole blood Mn was contained in the plasma fraction, though there was no association between whole blood and plasma Mn levels (Pearson's R,=,0.258, P,=,0.12). In contrast, in fresh whole blood samples spiked with Mn ex vivo ,80% or more of added Mn partitioned in the plasma, while only ,20% or less partitioned in the cellular fraction. Conclusions These data suggest a complex and limited relationship between exposure and blood Mn levels that may depend upon exposure attributes and the latency of blood sampling relative to exposure; plasma and urine Mn appear to be of little utility as exposure biomarkers. This underscores the need to fully characterize and validate these or other biomarkers for use in constructing appropriate exposure metrics and determining exposure,effect relationships. Am. J. Ind. Med. 50:801,811, 2007. © 2007 Wiley-Liss, Inc. [source] | |||||||||||||