27 research outputs found
Latitude gradient influences the age of onset of rheumatoid arthritis : a worldwide survey
The age of onset of rheumatoid arthritis (RA) is an important outcome predictor. Northern countries report an age of RA onset of around 50 years, but apparently, variability exists across different geographical regions. The objective of the present study is to assess whether the age of onset of RA varies across latitudes worldwide. In a proof-of-concept cross-sectional worldwide survey, rheumatologists from preselected cities interviewed 20 consecutive RA patients regarding the date of RA onset (RAO, when the patient first noted a swollen joint). Other studied variables included location of each city, rheumatologist settings, latitudes (10A degrees increments, south to north), longitudes (three regions), intracountry consistency, and countries' Inequality-adjusted Human Development Index (IHDI). Data from 2481 patients (82% females) were obtained from 126 rheumatologists in 77 cities of 41 countries. Worldwide mean age of RAO was 44 +/- 14 years (95% CI 44-45). In 28% of patients, RA began before age 36 years and before age 46 years in 50% of patients. RAO was 8 years earlier around the Tropic of Cancer when compared with northern latitudes (p <0.001, 95% CI 3.5-13). Multivariate analysis showed that females, western cities, and latitudes around the Tropic of Cancer are associated with younger age of RAO (R (2) 0.045, p <0.001). A positive correlation was found between the age of RAO and IHDI (r = 0.7, p <0.01, R (2) 0.5). RA often begins at an early age and onset varies across latitudes worldwide. We postulate that countries' developmental status and their geographical and geomagnetic location influence the age of RAO.Peer reviewe
Carbon and nitrogen mineralization in soil amended with phenanthrene, anthracene and irradiated sewage sludge
7 pages, 3 tables, 2 figures.Irradiation of sewage sludge reduces pathogens and can hydrolyze or destroy organic molecules. The effect of irradiation of sewage sludge on C and N dynamics in arable soil and possible interference with toxic organic compounds was investigated in soil microcosms using a clay soil. The soil was treated with phenanthrene and anthracene, with and without irradiated and non-irradiated sewage sludge amendment. All the treated soils were incubated for 182 days at 25 °C. The CO2 production and dynamics of inorganic N (NH4+, NO2â and NO3â) were monitored. Addition of sewage sludge (0.023 g gâ1 soil), anthracene or phenanthrene (10.0 ÎŒg gâ1 soil dissolved in methanol), and methanol (10 mg gâ1 soil) to soil had a significant effect on CO2 production compared to the control. However, there were no significant differences between soil treated with irradiated and non-irradiated sewage sludge. Irradiated sewage sludge increased the C and N mineralization of anthracene amended soils to a greater extend than in phenanthrene amended soils. Nitrification was inhibited for 28 days in soil treated with either methanol, anthracene and phenanthrene. Application of sewage sludge reduced such toxicity effects after 28 days incubation.The research was funded in part by the IAEA Co-ordinated Research Program under contract No. 8556/RO and by the department of Biotechnology and Bioengineering, CINVESTAV-
IPN, Mexico City, Mexico.Peer reviewe