33 research outputs found

    Residential mobility and childhood leukemia.

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    AimsStudies of environmental exposures and childhood leukemia studies do not usually account for residential mobility. Yet, in addition to being a potential risk factor, mobility can induce selection bias, confounding, or measurement error in such studies. Using data collected for California Powerline Study (CAPS), we attempt to disentangle the effect of mobility.MethodsWe analyzed data from a population-based case-control study of childhood leukemia using cases who were born in California and diagnosed between 1988 and 2008 and birth certificate controls. We used stratified logistic regression, case-only analysis, and propensity-score adjustments to assess predictors of residential mobility between birth and diagnosis, and account for potential confounding due to residential mobility.ResultsChildren who moved tended to be older, lived in housing other than single-family homes, had younger mothers and fewer siblings, and were of lower socioeconomic status. Odds ratios for leukemia among non-movers living <50 meters (m) from a 200+ kilovolt line (OR: 1.62; 95% CI: 0.72-3.65) and for calculated fields ≄ 0.4 microTesla (OR: 1.71; 95% CI: 0.65-4.52) were slightly higher than previously reported overall results. Adjustments for propensity scores based on all variables predictive of mobility, including dwelling type, increased odds ratios for leukemia to 2.61 (95% CI: 1.76-3.86) for living < 50 m from a 200 + kilovolt line and to 1.98 (1.11-3.52) for calculated fields. Individual or propensity-score adjustments for all variables, except dwelling type, did not materially change the estimates of power line exposures on childhood leukemia.ConclusionThe residential mobility of childhood leukemia cases varied by several sociodemographic characteristics, but not by the distance to the nearest power line or calculated magnetic fields. Mobility appears to be an unlikely explanation for the associations observed between power lines exposure and childhood leukemia

    The boomerang effect of radicalism in Discursive Psychology: A critical overview of the controversy with the Social Representations Theory.

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    This article provides a critical overview of the controversy between the Radical approach to Discursive Psychology (RDP) and the Social Representations Theory (SRT) and aims: a)?to show what is potentially complementary and contradictory in Discursive Psychology (DP) and the Social Representations Theory, when and why they are incompatible, and whether and how it is possible and/or desirable to integrate these two approaches. b)?to describe how the radicalism of the socio-constructionist thesis upheld by Discourse Analysis can give rise to several hard-to-solve problems, which may then be translated into a boomerang effect. In the final section, it highlights interest in dialog and “cross-fertilization” between researchers inspired by the less radical approach to discursive psychology and those inspired by the Social Representations Theory, pointing out the effect of methodological implications that would ensue

    Size Doesn't Matter: Towards a More Inclusive Philosophy of Biology

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    notes: As the primary author, O’Malley drafted the paper, and gathered and analysed data (scientific papers and talks). Conceptual analysis was conducted by both authors.publication-status: Publishedtypes: ArticlePhilosophers of biology, along with everyone else, generally perceive life to fall into two broad categories, the microbes and macrobes, and then pay most of their attention to the latter. ‘Macrobe’ is the word we propose for larger life forms, and we use it as part of an argument for microbial equality. We suggest that taking more notice of microbes – the dominant life form on the planet, both now and throughout evolutionary history – will transform some of the philosophy of biology’s standard ideas on ontology, evolution, taxonomy and biodiversity. We set out a number of recent developments in microbiology – including biofilm formation, chemotaxis, quorum sensing and gene transfer – that highlight microbial capacities for cooperation and communication and break down conventional thinking that microbes are solely or primarily single-celled organisms. These insights also bring new perspectives to the levels of selection debate, as well as to discussions of the evolution and nature of multicellularity, and to neo-Darwinian understandings of evolutionary mechanisms. We show how these revisions lead to further complications for microbial classification and the philosophies of systematics and biodiversity. Incorporating microbial insights into the philosophy of biology will challenge many of its assumptions, but also give greater scope and depth to its investigations

    Messa a punto di un metodo di misura del Sevofluorano urinario per il monitoraggio biologico delle esposizioni a basse concentrazioni

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    Vengono riportati i risultati preliminari delle associazioni tra i valori medi delle concentrazioni di sevoflurano (SF) e protossido d\u2019azoto (PA) nei campioni urinari di 65 soggetti professionalmente esposti a basse concentrazioni ed i valori medi ambientali degli stessi anestetici rilevati in 12 sale operatorie nel 2004 in un ospedale lombardo. I dati raccolti hanno dimostrato che la variabilit\ue0 statistica spiegata dai rilievi biologici \ue8 superiore per il SF rispetto al PA. Il coefficiente di correlazione lineare \ue8 risultato di 0,47 per il PA e di 0,63 per il SF. L\u2019ampiezza degli intervalli di confidenza sta ad indicare la considerevole variabilit\ue0 dei dosaggi biologici. Una ulteriore standardizzazione delle variabili individuali e della tecnica analitica potrebbero migliorare ulteriormente le associazioni riscontrate

    Assessing the impact of cancer among Dutch non-Hodgkin lymphoma survivors compared with their American counterparts:A cross-national study

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    Purpose To understand cultural differences in the impact of cancer (IOC) by (i) performing an independent psychometric evaluation of the Dutch version of the Impact of Cancer Scale version 2 (IOCv2) in a non-Hodgkin lymphoma (NHL) sample and (ii) examining differences between Dutch and American NHL survivors in perceived IOC and identifying associations with socio-demographic and clinical characteristics. Methods Data collected from 491 Dutch and 738 American NHL survivors were used in this study. IOCv2 responses were obtained from all survivors; the Dutch survivors also completed the European Organization for Research and Treatment of Cancer Quality of Life Core questionnaire, which measures quality of life. Results Exploratory factor analysis of the Dutch version yielded a factor solution similar to the American structure but with some subscales merging into single factors. Internal consistency was good; Cronbach's alpha was 0.88 for the Positive and 0.94 for the Negative summary scales. Large differences were observed between survivors, whereby Dutch survivors reported fewer Positive (Δ −0.4, p < 0.001, effect size: 0.27) and more Negative (Δ 0.2, p ≀ 0.001, effect size: 0.13) impacts of cancer independent of socio-demographic and clinical characteristics. Conclusion Similar impact domains of the IOCv2 were observed in the Dutch sample, providing evidence that IOCv2 scales measure common and important survivor concerns across two different Western nations. Higher positive impacts for US survivors might be explained by more personal control and availability of supportive services. Future research should focus on determinants of the IOC in both Dutch and American survivors to gain better understanding of the factors that might improve it and suggest how health care may be modified toward that end

    Cerebrospinal fluid of newly diagnosed amyotrophic lateral sclerosis patients exhibits abnormal levels of selenium species including elevated selenite.

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    Exposure to selenium, and particularly to its inorganic forms, has been hypothesized as a risk factor for amyotrophic lateral sclerosis (ALS), a fast progressing motor neuron disease with poorly understood etiology. However, no information is known about levels of inorganic and some organic selenium species in the central nervous system of ALS patients, and recent observations suggest that peripheral biomarkers of exposure are unable to predict these levels for several Se species including the inorganic forms. Using a hospital-referred case-control series and advanced selenium speciation methods, we compared the chemical species of selenium in cerebrospinal fluid from 38 ALS patients to those of 38 reference neurological patients matched on age and gender. We found that higher concentrations of inorganic selenium in the form of selenite and of human serum albumin-bound selenium were associated with increased ALS risk (relative risks 3.9 (95% confidence interval 1.2-11.0) and 1.7 (1.0-2.9) for 0.1&mu;g/L increase). Conversely, lower concentrations of selenoprotein P-bound selenium were associated with increased risk (relative risk 0.2 for 1&mu;g/L increase, 95% confidence interval 0.04-0.8). The associations were stronger among cases age 50 years or older, who are postulated to have lower rates of genetic disease origin. These results suggest that excess selenite and human serum albumin bound-selenium and low levels of selenoprotein P-bound selenium in the central nervous system, which may be related, may play a role in ALS etiology

    Recurrence rates of ocular toxoplasmosis during pregnancy

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    Purpose To investigate whether recurrence rates of ocular toxoplasmosis are higher during pregnancy in women of childbearing age. Design Retrospective longitudinal cohort study. Methods We reviewed medical records of all women seen at a university eye clinic (Utrecht, Netherlands) during episodes of active toxoplasmic retinochoroiditis that occurred while the women were of childbearing age (16-42 years). Each woman was sent a questionnaire requesting information regarding all pregnancies and episodes of ocular toxoplasmosis, whether or not episodes were observed at the eye clinic. Conditional fixed-effects Poisson regression was used to model incidence rate ratios of recurrence during pregnant versus nonpregnant intervals, adjusted for potential confounders, including age at time of active toxoplasmic retinochoroiditis and interval since last episode of active disease, which are known to influence risk for recurrence. Results Questionnaires were returned by 50 (58%) of 86 women, 34 of whom had had 69 pregnancies during 584 person-years of study. There were 128 episodes of ocular toxoplasmosis during the study period (6 during pregnancy). First episodes of ocular toxoplasmosis occurred between ages 9.6 and 38.5 years. The youngest age at pregnancy was 16.1 years; the oldest age at childbirth was 40.9 years. The incidence-rate ratios for pregnant versus nonpregnant intervals were in the direction of lower recurrence rates during pregnancy, with point estimates of 0.54 and 0.75 under 2 different approaches, but the ratios were not significantly different from the null value (P values of 0.16 and 0.55). Conclusions Recurrence rates of ocular toxoplasmosis are probably not higher during pregnancy, in contrast to traditional beliefs

    Inverse association between dietary vitamin D and risk of cutaneous melanoma in a northern Italy population.

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    The possibility of an inverse association between vitamin D and risk of cancer and, in particular, of cutaneous malignant melanoma has been suggested, but results of epidemiologic studies are still conflicting. We examined the relation between dietary vitamin D intake and melanoma risk through a population-based case-control study (380 cases, 719 controls) in a northern region of Italy, a country with an average vitamin D intake lower than that in northern Europe or the United States. We assessed average daily intake of vitamin D from foodstuffs using the European Prospective Investigation into Cancer and Nutrition (EPIC) semiquantitative food frequency questionnaire. In this population, levels of vitamin D intake were considerably lower than those observed in recent U.S. studies. We found an inverse relation between dietary vitamin D and melanoma risk in the sample as a whole, in both crude and adjusted analyses. In sex- and age-specific analyses, this association appeared to be stronger among males and among older subjects. These findings suggest that, at the relatively low levels of intake observed in this sample, an inverse relation between dietary vitamin D and risk of cutaneous malignant melanoma may exist
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