Characterization of magmatic sulfur in the Aegean island arc by means of the δ34S values of fumarolic H2S, elemental S, and hydrothermal gypsum from Nisyros and Milos islands

A delta(34)S value of +6.3 +/- 1.5% was estimated for the rhyodacitic degassing magma present underneath the hydrothermal system of Nisyros, based on the S isotope ratios of H2S in fumarolic vapors. This value was estimated by modeling the irreversible water-rock mass transfers occurring during the generation of the hydrothermal liquid which separates these fumarolic vapors. The S isotope ratio of the rhyodacitic degassing magma of Nisyros is consistent with fractional crystallization of a parent basaltic magma with an initial delta(34)S value of +4% (+/-at least 1.5%). This positive value could be explained by mantle contamination due to by either transference of fluids derived from subducted materials or involvement of altered oceanic crust, whereas contribution of biogenic sulfides from sediments seems to be negligible or nil. This conclusion agrees with the lack of N-2 and CO2 from thermal decomposition of organic matter contained in subducted sediments, which is a characteristic of the whole Aegean arc system. Since hydrothermal S at Milos and Santorini has isotope ratios similar to those determined at Nisyros, it seems likely that common controlling processes are active throughout the Aegean island arc. (C) 2002 Elsevier, Science B.V. All rights reserved.

A randomized trial of spiritual assessment of outpatients with schizophrenia: Patients' and clinicians' experience

Objective: Recovery-oriented care for patients with schizophrenia involves consideration of cultural issues, such as religion and spirituality. However, there is evidence that psychiatrists rarely address such topics. This study examined acceptance of a spiritual assessment by patients and clinicians, suggestions for treatment that arose from the assessment, and patient outcomes-in terms of treatment compliance and satisfaction with care (as measured by treatment alliance). Methods: Outpatients with psychosis were randomly assigned to two groups: an intervention group that received traditional treatment and a religious and spiritual assessment (N=40) and a control group that received only traditional treatment (N=38). Eight psychiatrists were trained to administer the assessment to their established and stable patients. After each administration, the psychiatrist attended a supervision session with a psychiatrist and a psychologist of religion. Baseline and three-month data were collected. Results: The spiritual assessment was well accepted by patients. During supervision, psychiatrists reported potential clinical uses for the assessment information for 67% of patients. No between-group differences in medication adherence and satisfaction with care were found at three months, although patients in the in- tervention group had significantly better appointment attendance dur- ing the follow-up period. Their interest in discussing religion and spirituality with their psychiatrists remained high. The process was not as well accepted by psychiatrists. Conclusions: Spiritual assessment can raise important clinical issues in the treatment of patients with chronic schizophrenia. Cultural factors, such as religion and spirituality, should be considered early in clinical training, because many clinicians are not at ease addressing such topics with patients.

Pediatric CT: how to compare the Present DRL Values? : 12.10

Purpose: To determine dose thresholds, in term of CTDIvol, where subtle anatomical structures of pediatric CT images becomes no more detectable and compare them to the most recent Reference Dose Levels (DRL) proposed in the UK, Germany and Switzerland. Materials and methods: A GE LightSpeed-Ultra scanner (MSCT 8 slices) was used to perform chest and abdomen acquisitions on 8 patients (age range 2 to 16 years old) to provide a set of gold standard images. Dose reductions were then simulated by introducing image noise on raw data to provide simulated CT images with CTDIvol ranging from 2 to 22 mGy. All images were reviewed and scored independently by four experienced radiologists using the VGA methodology (Visual Grading Analysis) to determine the dose threshold where a significant loss of normal anatomy conspicuity appeared. Data were analyzed with ANOVA and Tukey HSD tests, a p >0.05 was considered to be significant. Results: No significant difference in VGA scoring appeared for CTDIvol leading to image noise levels lower than 10 and 25 HU for respectively abdominal and chest acquisitions. These data can thus be used to set the AEC (automatic exposure control) system of units having similar noise properties than the GE LightSpeed-Ultra used in this study. The present DRLs proposed for pediatric CT acquisitions are compatible with an excellent image quality level. Conclusion: The differences of DRL values proposed in Europe for pediatric acquisitions are marginal and assure a very good image quality level. The results of this study allow to further optimize the acquisition protocol by giving Noise Index value to set the AEC device.

Using toxicokinetic modeling approach to determine biological reference values (BRVs) and to assess human exposure to pesticides

Exposure to various pesticides has been characterized in workers and the general population, but interpretation and assessment of biomonitoring data from a health risk perspective remains an issue. For workers, a Biological Exposure Index (BEI®) has been proposed for some substances, but most BEIs are based on urinary biomarker concentrations at Threshold Limit Value - Time Weighted Average (TLV-TWA) airborne exposure while occupational exposure can potentially occurs through multiple routes, particularly by skin contact (i.e.captan, chlorpyrifos, malathion). Similarly, several biomonitoring studies have been conducted to assess environmental exposure to pesticides in different populations, but dose estimates or health risks related to these environmental exposures (mainly through the diet), were rarely characterized. Recently, biological reference values (BRVs) in the form of urinary pesticide metabolites have been proposed for both occupationally exposed workers and children. These BRVs were established using toxicokinetic models developed for each substance, and correspond to safe levels of absorption in humans, regardless of the exposure scenario. The purpose of this chapter is to present a review of a toxicokinetic modeling approach used to determine biological reference values. These are then used to facilitate health risk assessments and decision-making on occupational and environmental pesticide exposures. Such models have the ability to link absorbed dose of the parent compound to exposure biomarkers and critical biological effects. To obtain the safest BRVs for the studied population, simulations of exposure scenarios were performed using a conservative reference dose such as a no-observed-effect level (NOEL). The various examples discussed in this chapter show the importance of knowledge on urine collections (i.e. spot samples and complete 8-h, 12-h or 24-h collections), sampling strategies, metabolism, relative proportions of the different metabolites in urine, absorption fraction, route of exposure and background contribution of prior exposures. They also show that relying on urinary measurements of specific metabolites appears more accurate when applying this approach to the case of occupational exposures. Conversely, relying on semi-specific metabolites (metabolites common to a category of pesticides) appears more accurate for the health risk assessment of environmental exposures given that the precise pesticides to which subjects are exposed are often unknown. In conclusion, the modeling approach to define BRVs for the relevant pesticides may be useful for public health authorities for managing issues related to health risks resulting from environmental and occupational exposures to pesticides.

Ascending aorta measurements as assessed by ECG-gated multi-detector computed tomography: a pilot study to establish normative values for transcatheter therapies

The aim of this study was to provide an insight into normative values of the ascending aorta in regards to novel endovascular procedures using ECG-gated multi-detector CT angiography. Seventy-seven adult patients without ascending aortic abnormalities were evaluated. Measurements at relevant levels of the aortic root and ascending aorta were obtained. Diameter variations of the ascending aorta during cardiac cycle were also considered. Mean diameters (mm) were as follows: LV outflow tract 20.3 +/- 3.4, coronary sinus 34.2 +/- 4.1, sino-tubular junction 29.7 +/- 3.4 and mid ascending aorta 32.7 +/- 3.8 with coefficients of variation (CV) ranging from 12 to 17%. Mean distances (mm) were: from the plane passing through the proximal insertions of the aortic valve cusps to the right brachio-cephalic artery (BCA) 92.6 +/- 11.8, from the plane passing through the proximal insertions of the aortic valve cusps to the proximal coronary ostium 12.1 +/- 3.7, and between both coronary ostia 7.2 +/- 3.1, minimal arc of the ascending aorta from left coronary ostium to right BCA 52.9 +/- 9.5, and the fibrous continuity between the aortic valve and the anterior leaflet of the mitral valve 14.6 +/- 3.3, CV 13-43%. Mean aortic valve area was 582.0 +/- 131.9 mm(2). The variation of the antero-posterior and transverse diameters of the ascending aorta during the cardiac cycle were 8.4% and 7.3%, respectively. Results showed large inter-individual variations in diameters and distances but with limited intra-individual variations during the cardiac cycle. A personalized approach for planning endovascular devices must be considered.

The quest for blood pressure reference values in children

Do we need country-specific blood pressure reference values for children? This question will sound weird for clinicians caring for adult hypertensive patients or researchers working in the domain of adult hypertension. Indeed, there are no country-specific reference values for adults. This contrasts with hypertension in children, for whom there is an increasing number of published sets of country-specific reference values [1-5].

Bruce Treadmill Test in Children : First Normal Values for Children from Western Europe : P67

Introduction: One of the main goals for exereise testing in children is evaluation of exercise capacity. There are many testing protocols, but the Bruce treadmill protocol is widely used among pediatrie cardiology centers. Thirty years ago, Cuming et al. were the first to establish normal values for children from North America (Canada) aged 4 to 18 years old. No data was ever published for children from Western Europe. Our study aimed to assess the validity of the normal values from Cuming et al. for children from Western Europe in the 21 st century. Methods: It is a retrospective cohort study in a tertiary care children's hospital. 144 children referred to our institution but finally diagnosed as having a normal heart underwent exercise stress testing using the Bruce protocol between 1999 and 2006. Data from 59 girls and 85 boys aged 6 to 18 were reviewed. Mean endurance time (ET) for each age category and gender was compared with the mean normal values fram Cumming et al by an unpaired t-test. Results: Mean ET increases with age until 15 years old in girls and then decreases. Mean endurance time increases continuouslY'from 6 to 18 years old in boys. The increase is more pronounced in boys than girls. In our study, a significant higher mean ET was found for boys in age categories 10 to 12, 13 to 15 and 16 to 18. No significant difference was found in any other groups. Conclusions: Some normal values from Cuming et al. established in 1978 for ET with the Bruce protocol are probably not appropriate any more today for children from Western Europe. Our study showed that mean ET is higher for boys from 10 to 18 years old. Despite common beliefs, cardiovascular conditioning doesn't seem yet reduced in children from Western Europe. New data for Bruce treadmill exercise. testing for healthy children, 4 to 18 years old, living in Western Europe are required. .

Reference values and factors associated with renal resistive index in a family-based population study.

Increased renal resistive index (RRI) has been recently associated with target organ damage and cardiovascular or renal outcomes in patients with hypertension and diabetes mellitus. However, reference values in the general population and information on familial aggregation are largely lacking. We determined the distribution of RRI, associated factors, and heritability in a population-based study. Families of European ancestry were randomly selected in 3 Swiss cities. Anthropometric parameters and cardiovascular risk factors were assessed. A renal Doppler ultrasound was performed, and RRI was measured in 3 segmental arteries of both kidneys. We used multilevel linear regression analysis to explore the factors associated with RRI, adjusting for center and family relationships. Sex-specific reference values for RRI were generated according to age. Heritability was estimated by variance components using the ASSOC program (SAGE software). Four hundred women (mean age±SD, 44.9±16.7 years) and 326 men (42.1±16.8 years) with normal renal ultrasound had mean RRI of 0.64±0.05 and 0.62±0.05, respectively (P<0.001). In multivariable analyses, RRI was positively associated with female sex, age, systolic blood pressure, and body mass index. We observed an inverse correlation with diastolic blood pressure and heart rate. Age had a nonlinear association with RRI. We found no independent association of RRI with diabetes mellitus, hypertension treatment, smoking, cholesterol levels, or estimated glomerular filtration rate. The adjusted heritability estimate was 42±8% (P<0.001). In a population-based sample with normal renal ultrasound, RRI normal values depend on sex, age, blood pressure, heart rate, and body mass index. The significant heritability of RRI suggests that genes influence this phenotype.

Religious coping in schizophrenia patients : spiritual support in medical care and pastoral counselling

Following an introduction focusing on the role of religion in the treatment of psychosis, the first part of this paper describes an initial study in which the role of spirituality and religiosity was assessed in 115 patients with schizophrenia in Geneva (Switzerland) and 126 in Trois-Rivières (Quebec). These themes have been shown to be highly prevalent for these patients, though their clinicians are often unaware of this prevalence. The following part of the paper presents a second study where religious supervision was offered to clinicians in Geneva. Comparison between forty patients who received spiritual assessment and opportunities to work on religious topics with their clinicians was made with thirty patients without religious intervention. In the supervisory sessions, six different types of religious interventions were suggested. Outcomes at three months show that patients of the intervention group maintain their interest for help in religious matters while clinicians' interest in integrating religious topics in discussions with their patients has decreased. The third and main part of the paper is devoted to an analysis of the suggested interventions from the viewpoint of the study of religions. Five aspects of religion are distinguished, and explanations of the reasons some of them are easier to manage for clinicians are proposed. The paper concludes with proposals for the education of clinicians to help them to differentiate different kinds of religious coping and to recognize when it could be helpful to refer the patient to a pastoral counsellor.