DCD was more effective than DMPP on increasing plant productivity. An increase of crop yield by DMPP was generally only observed in alkaline soil. The cost and benefit analysis (CBA) showed that applying fertilizer N with DCD produced additional revenues of $109.49 ha−1 yr−1 for maize farms, equivalent to 6.02% increase in grain revenues. In comparisons, DMPP application produced less monetary benefit of $15.67 ha−1 yr−1. Our findings showed that DCD had an advantage of bringing more net monetary benefit over DMPP. But this may be weakened by the higher toxicity of DCD than DMPP especially after continuous DCD application. Alternatively, an option related to net monetary benefit may be achieved through applying DMPP in alkaline soil and reducing the cost of purchasing DMPP products.Dicyandiamide (DCD) and 3, 4-dimethypyrazole phosphate (DMPP) are often claimed to be efficient in regulating soil N transformations and influencing plant productivity, but the difference of their performances across field sites is less clear. Here we applied a meta-analysis approach to compare effectiveness of DCD and DMPP across field trials. Our results showed that DCD and DMPP were equally effective in altering soil inorganic N content, dissolve inorganic N (DIN) leaching and nitrous oxide (N In addition, different crop types showed different responses to the application of NIs, which may be ascribed to their preference to the NH4+-N and NO3−-N1The efficiency of NIs depends on various conditions including soil factors, management factors, crop types, etc. For example, NIs appears to be more effective in soil which has the optimal range of pH values supported for soil nitrification. Meanwhile, efficiency of NIs positively varies with fertilizer N application rates for higher fertilizer N rates input often causing high N losset al.Recently, several meta-analyses related to NIs efficiency across sites have been conducted1916171819In this study, using a meta-analysis approach, we aimed to compare the efficiency of DCD and DMPP on altering soil inorganic N content, N leaching, gaseous emissions and plant productivity under various conditions including soil pH values, fertilizer N forms, fertilizer N rates and crop types. Additionally, we carried out a CBA for comparing monetary benefits between DCD and DMPP through deducting the application cost from the economic benefit of reducing N’s environmental impacts and increasing plant productivity.4+-N by 25.3% and 41.1%, and decreased soil NO3−-N content by 17.0% and 20.7%, respectively. These results showed that less than one-tenth of the application rate was enough for DMPP to get a similar inhibition effect compared to DCDWe found that DCD and DMPP were equally effective in altering soil inorganic N content at field scale for their confidence intervals overlapping each other . On aver4+-N and NO3−-N contents in both acid and alkaline soils .Previous field and laboratory studies on DCD and DMPP applications showed that they could reduce gaseous emission from soil, including NHmissions . This wa2O emission by 44.7% and 47.6%, respectively  estimated that DMPP reduced N2O emission by 50% (95% CI: 42% to 55%) through a meta-evaluation with the study number of 122O (95% CI: 40.3% to 51.8%) emission decreased by DMPP application (the number of observations was 23) for our meta-analysis including all previous studies  carried out a meta-analysis, and found that DCD was more effective than DMPP in reducing N2O emission. This discrepancy may be related to the different numbers of observations between the meta-analysis studies. The number of the observations in our study was larger  than the previous study . And both NIs had similar effectiveness under various conditions except that DMPP was more effective than DCD in neutral soils  through DMPP application  who demonstrated that the release of CO2 was reduced significantly on average for the 3 years observations. These researchers concluded that DMPP might affect C-mineralization in soil2 emission was unaffectedFor other gaseous emission, only COlication . This waMethane emission was not significantly altered by DCD and DMPP application , which pet al.Our meta-analysis results indicated that DCD significantly increased crop yield by 6.5%, while DMPP did not  . This waet al. (2014) who found that the overall effect of inhibitors (urease and nitrification inhibitors) on crop yield and NUE for neutral and alkaline soils was decreased through increasing N losses through NH3 volatilization. We thus separately evaluated the efficiency of DCD and DMPP in acid, neutral and alkaline soils , N loss factors of gaseous emission for DCD and DMPP application were 0.163 and 0.143, respectively (FN = 0.154). Overall, DCD and DMPP application resulted in a net reduction of the total N loss by 14.8% and 27.4%, respectively.Compared to N loss factors of conventional N fertilizer practice  for a maize farm in US−1. The revenue produced by DCD application in our study was lower than the revenue ($162.70 ha−1) of all NIs estimated by Qiao et al. (2015). These results above showed that DCD was more effective than DMPP in total revenue. However, DMPP exclusively focused on alleviating the environmental damage caused by dissolved inorganic N leaching.The results of CBA case study indicated that a total environmental benefit of $17.61 haur study . The mon−1 yr−1 in maize farms in term of impact of fertilizer N applications plus NIs. DMPP application brought less monetary benefit of $15.67 ha−1 yr−1 mainly because of no significant effect on crop yield and higher product price. Alternatively, DMPP application in alkaline soil might bring more monetary benefit than DCD even when the price of DMPP products became cheaper. Thus DMPP would be more accepted and popularly applied throughout the world in addition to the lower toxicity for plant growth. These findings highlight the interest in the efficient usage of DCD and DMPP for the future study. The efficiency of DCD and DMPP under continuously application in one given site is needed to examine. Meanwhile, the impact of their toxicity on plant growth and human health is also needed to study after years of application, although the toxicity of both NIs is low. Furthermore, the environmental impact of DCD and DMPP related to the release of NH3, NO, CO2 and CH4 from soil still needs more studies to confirm.Based on the results from our meta-analysis, we concluded that DCD and DMPP were equally effective in regulating soil N transformations across field sites worldwide. But the performance of DCD in increasing plant productivity was better than that of DMPP. Fertilizer N plus DCD could bring additional revenues of $109.49 haData were acquired by searching existing literature published before June 2015 using the ISI-Web of Science and Google Scholar. The following key words were used for searching such as meta-analysis, efficiency, nitrification inhibitor, DCD, DMPP, inorganic N, N leaching, gaseous emission and plant productivity. And the search terms were complemented with a search through the literature cited in the articles found. Papers were only included if they met the following criteria: 1) only field studies were selected and laboratory incubation studies were excluded; 2) at least one of the selected variables were measured; 3) means and sample sizes had to be reported; 4) treatment replicates were at least of three, etc. Then 81 peer-reviewed publications  across the world were selected for our analysis see .3, N2O, NO, CO2, CH4; plant productivity including biomass, crop yield, plant N uptake, etc). For visualizing the distribution of study sites around world, using ArcGIS software , we marked the study sites on the world map through adding data of longitude and latitude for study sites to the map layer. Then the study sites related to DCD application mainly distributed around the world, of which 5 sites located in China, 8 located in Western Europe, 6 located in India, 15 located in New Zealand, respectively. The study sites for DMPP mainly distributed in China (n = 9) and Western Europe (n = 14)  and Abalos et al. (2014) for comparative purposesFor each study, data were collected including study site location (longitude and latitude), soil characteristics , management measures (fertilizer N types and rates), crop types and the response variables  . Data wehina n =  and Westhina n =  and Westhina n =  and Westet al.The mean effect sizes were estimated using the formulas described by Bai eRi′ and wi′ are logeR′ and w′ of the ith observation. logeR′ is weighed effect size obtained by w′ and logeR.logeR was obtained after the log transformation of the ratio of its value in the DCD or DMPP treatment group (tX) to that in the control group (cX) for better statistical behavior.The effect size logw′ was calculated from equation w was calculated as the inverse of the pooled variance (1/v).eR was approximated using the following formula:The variance of logst and sc represent the standard deviations of treatment and control groups, respectively; nt and nc are the sample sizes for the treatment and control groups, respectively. If no standard deviation in studies was reported, we calculated the average coefficient of variation (CV) within each data set, and then approximated the missing standard deviation by multiplying the reported mean by the average CVThen a fixed-effects model option in software Metawin 2.1 was employed for calculation of grouped effect sizesFN) is the ratio of the amount of N fertilizer lost to environment to the amount of N fertilizer applied to soil3940FN + NI) was estimated by the following formula:N loss factor (M) of each variable was estimated by the formula.CBA was conducted in US maize farm as a case study. The net monetary benefit of NI application was assessed by summing environmental benefit including DIN leaching, GHG emission, crop yield and cost of purchasing NI products. NI’s impact on the economic value  on soil nitrogen transformations and plant productivity: a meta-analysis. Sci. Rep.6, 22075; doi: 10.1038/srep22075 (2016).


Temporal patterns of species abundance, although less well-studied than spatial patterns, provide valuable insight to the processes governing community assembly. We compared temporal abundance distributions of two communities, phytoplankton and fish, in a north temperate lake. We used both 17 years of observed relative abundance data as well as resampled data from Monte Carlo simulations to account for the possible effects of non-detection of rare species. Similar to what has been found in other communities, phytoplankton and fish species that appeared more frequently were generally more abundant than rare species. However, neither community exhibited two distinct groups of “core” (common occurrence and high abundance) and “occasional” (rare occurrence and low abundance) species. Both observed and resampled data show that the phytoplankton community was dominated by occasional species appearing in only one year that exhibited large variation in their abundances, while the fish community was dominated by core species occurring in all 17 years at high abundances. We hypothesize that the life-history traits that enable phytoplankton to persist in highly dynamic environments may result in communities dominated by occasional species capable of reaching high abundances when conditions allow. Conversely, longer turnover times and broad environmental tolerances of fish may result in communities dominated by core species structured primarily by competitive interactions. Understanding patterns in species abundance has been a central goal of ecology for several decades –4. MacroMany communities exhibit an occupancy-abundance relationship: generally, more common species  tend to be more numerically abundant than species observed infrequently . This paThe dramatic differences in the abundance of temporally common versus rare species has led to the hypothesis that communities are composed of two distinct groups: “core” and “occasional” species ,20,23. HCore and occasional species may vary in commonness and abundance because they have fundamentally different life history strategies and mechanisms controlling their abundance ,24. SpecAll communities studied to date have exhibited both core and occasional species, with the relative abundance of each group reflecting the importance of biotic and abiotic mechanisms in structuring the abundance distribution of the community on the temporal and spatial scale of sampling ,19,29. WThe relative balance of core and occasional species in a survey is also influenced by sampling effectiveness: i.e., even when a sampling protocol is standardized and extensive, it is likely that some species present in the community will not be detected  ,31. BecaIn this study, we examined temporal patterns of the relative abundances of two communities comprised of species with strongly contrasting life history strategies (phytoplankton and fish) that co-occurred in a highly variable environment . For thiWe used a 17-year dataset of phytoplankton and fish communities in a north temperate lake to ask two questions: 1) Do phytoplankton and fish exhibit a temporal occupancy-abundance relationship? and 2) What is the relative balance of core and occasional species within these two assemblages? Phytoplankton have short generation times (hours to weeks); high levels of dispersal via air, wind, water, animal vectors, and from dormant life stages in sediments; and can respond very quickly to perturbations . In addihttp://lter.limnology.wisc.edu/). Fish were captured following protocols approved by the University of Wisconsin-Madison Institutional Animal Care and Use Committee , and scientific collectors permits  issued by the Wisconsin Department of Natural Resources.All data in this study were collected as a part of the North Temperate Lakes Long Term Ecological Research Program and are publicly available online (NTL-LTER http://lter.limnology.wisc.edu). The dimictic lake has a mean residence time of 4.5 years, a surface area of 39 km2, and a mean and maximum depth of 12 and 25 m, respectively. Within a year, this ecosystem experiences substantial variability in its physics, chemistry, and biology  that has been extensively studied for over a century , andhttp://lter.limnology.wisc.edu). In brief, phytoplankton from the deep hole were collected biweekly  to monthly during the open-water period with an integrated 8 m tube, pooled into a composite 0–8 m sample, and immediately preserved with gluteraldehyde. More than 400 natural units  were identified to species per sample using an inverted microscope and reported as cell densities mL-1 [3. To be comparable with the fish, we conducted all phytoplankton analyses using cell densities because we were primarily interested in phytoplankton relative abundances, not biovolume. Importantly, the same taxonomist was responsible for all phytoplankton identification throughout the sampling period. Cells that were not taxonomically resolved to species were excluded from our analysis.As part of its routine LTER monitoring, phytoplankton and fish communities in Lake Mendota were sampled during 1995–2011  were influenced by stocking throughout the study period as part of fisheries management and a biomanipulation project to improve water clarity [Fish were collected yearly in late summer with several gear types designed to sample littoral and pelagic habitats following long-term established protocols. Gear consisted of beach seines, minnow traps, and fyke nets at six littoral sites; a boat-mounted electrofishing system for three littoral transects; vertically hung gill nets for two pelagic samples at the deep hole; and a trammel net across the thermocline at two sites ,45,46. T clarity , the excTo ease comparison between the two communities and ensure that sufficient sampling effort was expended on both phytoplankton and fish, we constructed species accumulation curves in the R package vegan  using thTo further make the sampling interval of the phytoplankton data comparable with the yearly fish measurements, we pooled all open-water samples collected within the same year. Lake Mendota’s phytoplankton community exhibits substantial seasonal succession , so compFor the analyses presented here, we focused on the observed composition and relative abundance of species in the phytoplankton and fish communities, as has been done in the vast majority of previous studies examining species abundance distributions. Observed species data are influenced by both the actual species abundances as well as sampling error in monitoring, such as the failure to detect or identify a species in a given year when it is actually present due to its patchiness or rarity, i.e., a false negative . Given tp for each species, in which p = number of years a species was observed divided by the total number of years sampled . Consequently, observed abundance did not directly determine a species’ p, but may have influenced it by altering the number of years a species was observed.Following , we condp to sample observed relative abundances with replacement. This process was simulated 10,000 times to generate a distribution of resampled relative abundances and numbers of years each species was observed over the 17-year monitoring period that included the effect of sampling error. The maximum relative abundance of each species in each of the 10,000 simulations was used to calculate the standard deviation of relative abundance attributable to sampling error [To generate resampled data for each community, we created a matrix of the relative abundance of each species in each sampling year using the probability ng error .p to generate new distributions of resampled relative abundance as the number of total years a species was observed increased by one (only for species with p < 1). Thus, for the 16th iteration , all species were observed every year and every species’ p = 1.To further assess the effects of false negatives on our results, we examined how increased detection of each species in additional years would influence our conclusions. We repeated the Monte Carlo simulations 16 additional times, each time sequentially adding 0.0588 (1/17 years) to each species’ 10-transformed) in any year against the number of years a species was observed [We conducted all analyses on both the observed and resampled data. Within each community and year, we assigned each species a rank based on their maximum observed or resampled relative abundance on any sampling day in that year (highest relative abundance species = rank 1). To assess whether a relationship existed between observed temporal occurrence and relative abundance, we regressed the maximum observed abundance  was examined; this is the temporal analogue to a spatial metapopulation analysis  used to Finally, to assess the influence of temporal frequency on static depictions of community structure, we generated single rank abundance distributions (RAD) for each community using both the observed and resampled relative abundances. In this case, we ranked species based on their highest observed or resampled relative abundances observed in the entire time period, and examined the location of core vs. occasional species within the RAD ,32. All During the open water period in 1995–2011, we observed in total 254 species of phytoplankton and 36 species of fish. The total (summed) observed relative abundance of both communities varied substantially over time: phytoplankton and fish exhibited greater than five-fold differences in their relative abundance  among years . Phytopl10(phytoplankton maximum density) = 1.56 + 0.15 × years in dataset, adjusted R2 = 0.32, p<0.00001; Log10(fish maximum density) = -0.54 + 0.11 × years in dataset, adjusted R2 = 0.60, p<0.00001). This relationship was robust both within phytoplankton divisions and fish families, as well as across the aggregated community for both phytoplankton and fish.Both the observed phytoplankton and fish communities exhibited positive temporal abundance-occupancy relationships, demonstrated by significant positive slopes relating maximum density of a species to the number of years in which it was observed (th percentile of relative abundance for those years), and some core species were not abundant . This pattern was especially apparent for fish , while rOverall, the observed phytoplankton community was dominated by occasional species with few core species, while the observed fish community was dominated by core species with few occasional species . The freThe difference in the relative balance of core and occasional species in the two observed communities can also be observed in their static rank abundance distributions (RAD). When aggregated across all years, the RAD of observed phytoplankton data does not show distinct groupings of both core and occasional species . Occasio10(standard deviation of resampled maximum phytoplankton relative abundance) = 0.72–0.05 × years in dataset, adjusted R2 = 0.31, p<0.00001). By comparison, the number of years observed in the dataset did not affect the variation in resampled maximum relative abundance for the fish species (10(standard deviation of maximum resampled fish relative abundance) = 0.11–0.002 × years in dataset, adjusted R2 = 0.01, p = 0.49). The sampling error in the occasional phytoplankton species was evident in the histogram of species proportions  = 1.52(1.28–1.73) + 0.13(0.11–0.16) × years in dataset, adjusted R2 = 0.29(0.20–0.42), all p<0.00001; Log10(fish maximum density) = -0.73(-1.38–0.36) + 0.12(0.09–0.15) × years in dataset, adjusted R2 = 0.59(0.36–0.79); all p<0.00001). The temporal abundance-occupancy relationships based on resampled data were robust both within phytoplankton divisions and fish families. The core species of both communities tended to exhibit the highest resampled relative abundances, with much more variability in the phytoplankton relative abundances than in those of the fish  55% ± 22% (1 S.D.) of the total observed relative abundance in any given year (range over 17 years was 25%–90%). By comparison, the 11 observed core fish species composed (on average) 92% ± 0.04% of total fish relative abundance (range = 81%–98%), which is similar to the dominance of core species observed in other studies. For example, three estuarine fish species accounted for over 70% of the total abundance in any given year in a 21-year study , and thrAs in any study of species presence and absence, our observed results assume that sampling was sufficient to detect rare species when they were present. However, it is possible that absences in the observed dataset could be a result of sampling failure to detect a species. The issue of non-detection was particularly important for occasional phytoplankton species , becauseImportantly, our conclusions are robust to false negative observations. The resampled data show a similarly strong temporal abundance-occupancy relationship as the observed data for both communities , and demThe life-history traits of phytoplankton and fish combined with the dynamic environment of Lake Mendota may help explain the high proportion of occasional phytoplankton species and core fish species. Occasional species are specialists that take advantage of rare environmental conditions  or migraThe importance of both dynamic environmental conditions and high dispersal and turnover rates for producing elevated numbers of occasional species is illustrated by the relative lack of occasional species in a previous study of the temporal abundance patterns of ciliates in the Mediterranean Sea . Althoughttp://www.fishbase.org/), and are thus not capable of much population turnover as conditions change between yearly sampling dates. Fish are also much more limited than phytoplankton in their ability to disperse among lakes, restricted by surface water connections and human-mediated transport [Moxostoma macrolepidotum) and silver redhorse (Moxostoma anisurum)  See  – are boThe temporal duration of sampling plays an important role in abundance distributions ,19,29,32Gloeotrichia echinulata, a cyanobacterium that appears in Lake Mendota, produces colonies that are 1–3 mm in diameter and can survive in the water column up to 21 days [G. echinulata was only observed in 4 out of 17 years. These data suggest that our results are robust to sampling frequency.To investigate if sampling scale altered the likelihood of observing occasional phytoplankton species, we conducted two additional analyses. First, we examined the frequency distributions of observed phytoplankton relative abundance within each year, using individual sampling dates as replicates  and foun 21 days ,57. ThusExamining multiple communities with contrasting life history strategies and dispersal abilities in the same environment can provide insight into mechanisms structuring communities at different taxonomic levels while controlling for environmental differences . In thisS1 Fig(TIFF)Click here for additional data file.S1 Table(DOCX)Click here for additional data file.


The coefficient of determination between observed and predicted values were r2 = 0.32 for CO, r2 = 0.26 for H and r2 = 0.52 for BA. The models obtained were able to adequately estimate BA and CO. In summary, it can be concluded that relief variables are good predictors of vegetation structure and enable the creation of forest structure maps in primary tropical rainforest with an acceptable uncertainty.Surveying primary tropical forest over large regions is challenging. Indirect methods of relating terrain information or other external spatial datasets to forest biophysical parameters can provide forest structural maps at large scales but the inherent uncertainties need to be evaluated fully. The goal of the present study was to evaluate relief characteristics, measured through geomorphometric variables, as predictors of forest structural characteristics such as average tree basal area (BA) and height (H) and average percentage canopy openness (CO). Our hypothesis is that geomorphometric variables are good predictors of the structure of primary tropical forest, even in areas, with low altitude variation. The study was performed at the Tapajós National Forest, located in the Western State of Pará, Brazil. Forty-three plots were sampled. Predictive models for BA, H and CO were parameterized based on geomorphometric variables using multiple linear regression. Validation of the models with nine independent sample plots revealed a Root Mean Square Error (RMSE) of 3.73 m Deforestation and forest fragmentation by human activities are some of the main environmental problems of tropical forests. The destruction and degradation of the forest cover decreases its ecological integrity, decreasing biodiversity and negatively impacting the functioning of these systems ,2. ThereForest structure can affect several ecosystem processes ,4,5 and Average tree basal area (BA) and height (H) of trees and average percentage of canopy openness (CO) are often used to describe forest structure. Together, these parameters can offer a general view of the vegetation structure, which can be determined from different environmental factors, namely relief, soil, temperature, water availability, geological structure or fire incidence ,19,20,21In the present study relief was represented by local geomorphometric characteristics, such as elevation, slope gradient and slope aspect, which strongly affect vegetation structure ,22,23. ESeveral studies have analysed the influence of environmental variability on spatial differentiation of vegetation. However, few have rigorously tested the effects of local geomorphometric variation on the structural characteristics of vegetation ,29,30, sAs geomorphometric variables are available from satellite missions such as the Shuttle Radar Topography Mission (SRTM), they offer a methodological approach for indirect estimation and mapping of forest structural variables at larger scales, if robust relationships between the two are confirmed. The magnitude of the uncertainties in forest structure maps from geomorphometric proxies needs to be carefully quantified. Thus, because relief characteristics are related to vegetation structure ,36, the The study area belongs to the Tapajós National Forest (TNF), between coordinates 2°35’ to 4°20’S and 54°40’ to 55°40’ W, located in the Lower Amazon River mesoregion, Western of Pará State, Brazil . The TNFThe region's climate is Ami type, according to the Köppen climate classification, with approximately 25°C annual average temperature, 1800 mm annual average rainfall, and higher rainfall concentration between January and May . The pre2, in a total area of 10.75 ha. In the present study, the surveyed plots presented different topographic positions and phyto-ecological classes, defined according to floristic, lithological and geomorphological characteristics of the TNF [A survey of the forest structure was performed in 43 plots with 25 x 100 m the TNF .The vegetation typology in this area consist mostly of dense tropical rain forest and a small portion of open tropical rain forest in the southwest area of TNF. Within the 10.75 ha total sampled area, the elevation varies between 81 and 218 m, whereas slope varies from 2 to 27%. In total, 4163 arboreal individuals (49 plant families and 232 species) were found during the field work. Bispo et al.  in theirThe geographic position of diameter at breast height (DBH) and total height (H) were measured for all tree individuals with DBH ≥ 10 cm in each plot. Averages diameter at breast height, averages at height and canopy openness (CO) were therefore recorded for all plots. Tree basal area (BA) was calculated using DBH according to the following equation:Tree height (H) was visually assessed by a trained specialist. To improve visual estimates, these data were adjusted using the equation developed by Gonçalves et al. , which wWhere Hce represent the tree height measured using an electronic clinometer and Hev represent tree height visually assessed.DBH was measured using a measuring tape. CO was estimated from hemispherical images obtained using a digital camera with 10.2 Megapixel resolution (Nikon D60) coupled to a wide-angle lens (fisheye) (Soligor 0.25x52 mm). The images were captured 1.8 m from the ground, with a 90 degree angle relative to the ground, under the canopy and avoiding direct sunlight, i.e., under conditions of uniform sky before sunrise (from 6:30 to 8:30 am) or after sunset (3.30 to 5:00 pm). These images were taken along central axis transects (25 x 100 m), every 20 m , totaliTo facilitate data integration, analysis and to enable the performance of spatial queries, the dendrometric parameter data were structured using the Geographic Information System (GIS).The geomorphometric data used  were obtained from the Brazilian Geomorphometric Data Bank (TOPODATA) . For thehttp://www.dsr.inpe.br/topodata/acesso.php). The geomorphometric variables obtained from TOPODATA are presented in There was a preference to use TOPODATA instead of the original SRTM. as it includes the derivations calculated with algorithms specially developed for the SRTM characteristics, which were widely tested on varied reliefs in order to run uniformly on the full extension of the Brazilian territory  In additGeomorphometric data layers included elevation, slope, aspect and profile and plan curvatures, as described. Since aspect is a circular variable, its linear components given by sine/cosine transformation were used for regression analyses instead.Local geomorphometric data were obtained from the TOPODATA in GeoTIFF format, from the elevation image  and its derivations. For each variable, the grids (1° x 1.5° each) covering the study area were concatenated into an image mosaic.The two datasets (vegetation and geomorphometric data) were overlaid after matching their respective georeference systems by reprojecting the raster images and plot polygons to a common projection. Geomorphometric data were averaged within plot extents and extracted in correspondence to vegetation data, resulting in paired datasets for further analysis in statistical software environments.Predictive models were generated for each variable  based on local geomorphometric variables using multiple regression analyses . Indepen2).The models were built using thirty observations and were validated using nine independent observations. Model validation was performed by comparing observed and model-predicted values using the RMSE (Root Mean Square Error)  and the p>0.05) and did not present spatial autocorrelation for any distance class according to Moran's Index (p>0.05). The plot of residuals against predicted values showed that the linearity and homoscedasticity assumptions were met.The models obtained were statistically significant. The data analysed showed VIF < 10, indicating the absence of serious problems with multicollinearity  Table 2Table 2. 2 = 0.68, Adjusted r2 = 0.66, F2.27 = 29.809, p<0.001 and Std. Error of Estimate = 4.1207) and included the explanatory variables elevation and slope gradient  and included the variables profile curvature and slope gradient  and included the variables elevation, cosine of the orientation slope, and profile curvature  for BA, 1.70 m (12%) for H, and 1.78% (21%) for CO relative to the average values. The coefficients of determination from the analyses between observed and predicted values were r2 = 0.32 for CO, r2 = 0.26 for H and r2 = 0.52 for BA. Because the coefficient of determination of the modelled H with 30 samples was low and that one generated with the independent observations to this structural variable was not significant, we considered the obtained model inadequate for estimation of this variable. Following validation, the models for BA and CO were applied, and maps for these two variables were generated for TNF  , Fig 3.2 for the model was only approximately 26%, meaning that only a small proportion of the variability in H was explained by the model. In this case, considering the 9 independent validation sample plots, the coefficient of determination between observed and predicted H values was not significant. Therefore it can be considered that the multiple regression models were not satisfactory for this variable. In summary, we conclude that the relief variables used were only sufficient to adequately estimate BA and CO. In the case of H, including additional variables in the model, such as the type of soil, geological structure and water availability, may improve its predictive capacity.Our data have revealed that topographic relief is a good predictor of certain forest structural characteristics. Of the three geomorphometric characteristics measured, average basal area (BA) and average canopy openness (CO) were adequately predicted by relief, although comparing the results we can notice that the model generate by BA is adjusted better than CO. For average height (H), although the error was low (RMSE = 12%), the rThe basal area estimates included the variables altitude and slope gradient, whether the canopy openness estimates included altitude, profile curvature and cosine of slope aspect. Of these variables, altitude may be considered the one variable with higher predictive capacity of vegetation structure, since its variation was highly consistent with the spatial variation of the basal area and canopy openness estimates. The estimates generated by the models revealed that sites presenting higher CO also presented tree individuals with lower BA and that higher CO and lower BA occurred in areas with lower altitude. Therefore, we suggest that altitude is the main predictor variable of spatial macro-variation of forest structure in the study area. The remaining variables included in the models  seem to be related with minor components of this variation.Relief characteristics, such as those evaluated through geomorphometric variables in the present study, have previously been considered as determinants of vegetation structure in forest ecosystems ,29,36,49Regions closer to the Tapajós River present Dystrophic Yellow Oxisol with medium texture, from clayey to sandy (dystrophic Entisols), dense forest/savanna transition, and flat to mildly hilly relief. Due to the dense forest/savanna transition, these areas present a slightly lower tree density. The models generated in the present study showed higher CO and individuals with lower BA in these areas. These forest characteristics can also be found in areas more to the southwest and extreme south of the TNF, with the occurrence of more open forests.In contrast, TNF areas with higher altitude generally presented higher BA and lower CO. As previously stated, these areas present more clayey soils and, consequently, higher carbon and nitrogen concentrations, which enables higher vegetation development. These results are corroborated by Castilho et al. , who stuThe relationships discussed above show that most effects of relief on vegetation can be explained by their relationships with the soil type, especially when different altitudes are compared. Different soil types present important nutritional differences, which could partly explain the vegetation structure variation. For example, in general, greater forest structure or biomass is expected in more fertile soils, independently of the species composition, simply because there are more resources available to support plant growth . These fThe intensity of the impact of human activities on vegetation structure can be evaluated by comparing pre-existing and current vegetation ,58. ConsFuture steps to refine this variable integration for other Amazon mesoregions are needed to increase knowledge and to supply tools to help with control and supervision policies for the environmental monitoring organs of this region. The availability of satellite-derived global digital terrain models such as SRTM and the TanDEM-X DEM, which is currently in production, are a valuable resource for the indirect mapping of forest structural parameters in primary tropical forest. These maps will be useful for improving regional or global monitoring of forest structure and biodiversity in Amazon Biome.The study was carried out in the Tapajós National Forest (TNF) and dendrometric measurements (diameter at breast height and height) as well as botanical identification of the trees were done, just inside of this area. The authorization to carry out the field work at TNF was provided by the Instituto Chico Mendes de Conservação da Biodiversidade-ICMBio/MMA (SISBIO n. 20591–1). This study did not involve endangered or protected species and no biological samples were taken.S1 File(DOCX)Click here for additional data file.S1 Table(XLSX)Click here for additional data file.S2 Table(XLSX)Click here for additional data file.


PV is a Ph-negative MPN characterized by erythrocytosis and the presence of an activating JAK2 mutation in >95% of cases. PV and CML are considered to be mutually exclusive; however, rare cases of concurrent Ph-positive CML and a JAK2 V617F-positive PV have been described in the literature.9 Previous reports have suggested that the two disorders may arise independently,4 or from within the same clone,9 but definitive clonal analysis has never been documented. We report a case of a patient with JAK2 V617F-positive PV who subsequently developed chronic phase Ph-positive CML. The patient was successfully treated with the combination of dasatinib and ruxolitinib. Cytogenetic and molecular responses suggested that the two disorders arose independently, which was corroborated by genotyping analyses of single-cell-derived colonies.Myeloproliferative neoplasms (MPNs) are myeloid malignancies characterized by stem cell-derived clonal myeloproliferation. There are seven designated conditions under the category of MPNs including chronic myelogenous leukemia (CML) and polycythemia vera (PV).9/l and a Hgb of 9.5 g/dl. Examination of the peripheral smear demonstrated leukoerythroblastic changes with few circulating blasts. A bone marrow biopsy showed hypercellularity with granulocytic and megakaryocytic hyperplasia, no excess blasts, and moderate fibrosis on reticulin staining. A diagnosis of post-PV myelofibrosis was initially suspected; however, cytogenetics showed t in 20 out of 20 metaphase cells and fluorescence in situ hybridization for BCR-ABL was positive (92.5%). Quantitative PCR for JAK2 V617F revealed an allele burden of 6%. Therefore, it appeared that the patient had developed CML with relative clonal dominance over PV.A 55-year-old woman was first diagnosed with PV in 2001 when she presented with a hemoglobin (Hgb) of 20.0 g/dl. Over the ensuing 10 years, the patient was treated with aspirin and intermittent hydroxyurea and anagrelide, with poor compliance. In May 2011 , she presented with worsening fatigue, weight loss and splenomegaly. Laboratory studies revealed an elevated white blood cell count (WBC) of 45 × 109/l, Hgb 12.3 g/dl and platelet count of 799 × 109/l. BCR-ABL by fluorescence in situ hybridization had decreased to 4.0% however, the JAK2 V617F allele burden had increased to 83% . Despite minimal residual clonal burden from CML, the patient continued to report fatigue and poor appetite, progressive weight loss of 15 pounds and persistent splenomegaly.The patient was treated with hydroxyurea without significant improvement in leukocytosis or thrombocytosis, and there was also no response when hydroxyurea was changed to anagrelide. A repeat bone marrow biopsy performed in May 2012 (300 days after initiation of dasatinib) revealed a hypercellular marrow, no increased blasts and severe fibrosis on reticulin staining. Cytogenetic analysis demonstrated a complete cytogenetic response with 9/l, Hgb 11.9 g/dl, platelets 297 × 109/l), as well as improvement in constitutional symptoms and splenomegaly. The patient tolerated treatment with the combination of ruxolitinib and dasatinib well, but was noted to have worsening anemia in September 2012, approximately 4 months after starting treatment with both therapies. She was advised to hold ruxolitinib but accidentally held dasatinib for 1 month. Subsequently, dasatinib was resumed and ruxolitinib was held in October 2012 for a month, following which the patient's Hgb improved, and she was restarted on ruxolitinib at a decreased dose of 5 mg twice daily. Two months later, the dose of ruxolitinib was increased to 10 mg alternating with 5 mg twice daily.Owing to the progressive increase in counts, ongoing constitutional symptoms and poor tolerance of hydroxyurea, treatment with ruxolitinib 10 mg twice daily was commenced (in addition to continuation of dasatinib) in June 2012. Within 6 weeks, there was significant improvement in the patient's blood counts ,8 including a recently published report of two patients with PV/CML who were treated with the combination of imatinib and ruxolitinib.9 Similar to our case, treatment with imatinib did not lead to improvement in constitutional symptoms or splenomegaly in either patient, although they both achieved complete cytogenetic and major molecular responses of their CML. The addition of ruxolitinib to imatinib in both cases produced an improvement in constitutional symptoms and splenomegaly; however, both patients required dose reductions of ruxolitinib and imatinib owing to hematologic toxicity.Several other case reports observed a similar increase in the BCR-ABL and JAK2 V617F during treatment; however, it is still possible that these two clones originated from a shared ancestral clone.To our knowledge, this is the first case report of a patient with concurrent PV and CML treated with a JAK inhibitor and a second generation ABL TKI that definitively demonstrates that the two neoplasms arose from separate clones. None of the prior case reports included correlative clonal analysis of patients treated with this combination of therapy. Genotyping of individual progenitor colonies suggests that the two disorders arose from independent clones, which is consistent with the findings from serial quantitative measurements of The combination of ruxolitinib and dasatinib was safe and effective in the treatment of concomitant PV and CML in this patient. The optimal schedule of treatment  for treatment of patients with concomitant PV/CML is still unclear, but can potentially be guided by molecular monitoring and biologic correlative analyses. Ultimately, the best treatment approach will be determined by the kinetic dynamics of each clone and the tolerability of combining TKIs.


In a double-blind randomized controlled trial, Esther Atukunda and colleagues evaluated whether sublingual misoprostol administered to women in labor was non-inferior to intramuscular oxytocin in preventing postpartum hemorrhage and reducing blood loss.Please see later in the article for the Editors' Summary Postpartum hemorrhage (PPH) is a leading cause of maternal death in sub-Saharan Africa. Although the World Health Organization recommends use of oxytocin for prevention of PPH, misoprostol use is increasingly common owing to advantages in shelf life and potential for sublingual administration. There is a lack of data about the comparative efficacy of oxytocin and sublingual misoprostol, particularly at the recommended dose of 600 µg, for prevention of PPH during active management of labor.We performed a double-blind, double-dummy randomized controlled non-inferiority trial between 23 September 2012 and 9 September 2013 at Mbarara Regional Referral Hospital in Uganda. We randomized 1,140 women to receive 600 µg of misoprostol sublingually or 10 IU of oxytocin intramuscularly, along with matching placebos for the treatment they did not receive. Our primary outcome of interest was PPH, defined as measured blood loss ≥500 ml within 24 h of delivery. Secondary outcomes included measured blood loss ≥1,000 ml; mean measured blood loss at 1, 2, and 24 h after delivery; death; requirement for blood transfusion; hemoglobin changes; and use of additional uterotonics.p<0.001; absolute risk difference 11.2%, 95% CI 6.44 to 16.1). Severe PPH occurred in 20 (3.6%) and 15 (2.7%) participants in the misoprostol and oxytocin groups, respectively . Mean measured blood loss was 341.5 ml (standard deviation [SD] 206.2) and 304.2 ml  at 2 h and 484.7 ml (SD 213.3) and 432.8 ml  at 24 h in the misoprostol and oxytocin groups, respectively. There were no significant differences between the two groups in any other secondary outcomes. Women in the misoprostol group more commonly experienced shivering  and fevers .At 24 h postpartum, primary PPH occurred in 163 (28.6%) participants in the misoprostol group and 99 (17.4%) participants in the oxytocin group . Almost all of these “maternal” deaths occur in low- or middle-income countries, and most are caused by a handful of preventable or treatable conditions—postpartum hemorrhage (severe bleeding from the uterus [womb] within 24 hours of childbirth), post-delivery infections, unsafe abortion, obstructive (difficult) labor, and blood pressure disorders during pregnancy. The leading cause of maternal deaths worldwide is postpartum hemorrhage, which is responsible for 25%–30% of all maternal deaths. Postpartum hemorrhage can be prevented by giving the mother an intramuscular injection of oxytocin, a hormone that stimulates uterine contractions and limits uterine bleeding, immediately after her child is born.Unfortunately, oxytocin needs to be kept cool, which limits its use in low- and middle-income countries, and, until recently, it was thought that only trained personnel could give intramuscular injections. Consequently, administration of misoprostol, a synthetic prostaglandin that has effects similar to those of oxytocin, has been proposed as an alternative way to prevent postpartum hemorrhage in resource-limited settings. Misoprostol is stable at room temperature, and because it can be given sublingually (beneath the tongue), it acts very quickly. However, the comparative efficacy of sublingual misoprostol and intramuscular oxytocin for the prevention of postpartum hemorrhage has not been established. Here, the researchers undertake a double-blinded, double-dummy randomized controlled non-inferiority trial to compare sublingual misoprostol and intramuscular oxytocin for the prevention of postpartum hemorrhage in Uganda, a country where there are more than 5,500 maternal deaths every year. A randomized controlled trial compares the outcomes of individuals assigned to different interventions through the play of chance. In a double-blinded trial, neither the researchers nor the participants know who is receiving which intervention. In this particular trial, double-blinding is achieved by giving a dummy (placebo) sublingual pill to the women assigned to the oxytocin group and a dummy injection to the women assigned to the misoprostol group, as well as their assigned treatments. A non-inferiority trial investigates whether one treatment is not worse than another treatment.The researchers measured blood loss over the first 24 hours after delivery in 1,140 women admitted to a regional referral hospital in Uganda. The women were given either sublingual misoprostol or intramuscular oxytocin at the currently recommended doses, along with matching placebos, immediately after the birth of their child. Postpartum hemorrhage  occurred in 28.6% and 17.4% of the women in the misoprostol and oxytocin groups, respectively (an absolute risk difference of 11.2%). Severe postpartum hemorrhage  occurred in 3.6% and 2.7% of participants in the misoprostol and oxytocin groups, respectively, but this difference was not statistically significant (it could have happened by chance). On average, women given misoprostol had lost slightly more blood by two and 24 hours after delivery than those given oxytocin. There were no significant differences between the groups in terms of death, the need for blood transfusion, or the use of additional drugs to prevent blood loss, but women given misoprostol experienced shivering and fever more often than those given oxytocin.In their study protocol, the researchers specified that sublingual misoprostol would be deemed non-inferior to intramuscular oxytocin if the absolute risk difference for postpartum hemorrhage between the misoprostol and oxytocin treatment groups was less than 6% (the “non-inferiority” margin). These findings therefore indicate that sublingual misoprostol given at the recommended dose is inferior to intramuscular oxytocin for the prevention of postpartum hemorrhage in women undergoing an uncomplicated birth at a regional referral hospital in Uganda. Although several aspects of this study may affect the accuracy and generalizability of its findings , the researchers conclude that oxytocin should remain the preferred agent for the prevention of postpartum hemorrhage where it is available. However, they note, sublingual misoprostol remains important for the prevention of postpartum hemorrhage where oxytocin is unavailable or its administration is not feasible.http://dx.doi.org/10.1371/journal.pmed.1001752.Please access these websites via the online version of this summary at maternal mortality; “Trends in Maternal Mortality: 1990 to 2013” is a recent WHO/UNICEF/UNFPA/World Bank publication that provides up-to-date information on maternal mortality worldwideThe United Nations Children's Fund (UNICEF) provides information on maternal health The World Health Organization provides information on Postpartum Hemorrhage Prevention and Treatment Website provides a forum for information sharing and learning between organizations and individuals working on the prevention and treatment of postpartum hemorrhage in developing countries; the website includes basic information about postpartum hemorrhage and links to additional resourcesThe “Veil of Tears” contains personal stories (including stories about postpartum hemorrhage) from Afghanistan about loss in childbirth“Maternal Death: The Avoidable Crisis” is a briefing paper published by Médecins Sans Frontières in 2012trial is availableMore information about this  Of the estimated 287,000 maternal deaths worldwide, 85% occur in low- and middle-income countries Oxytocin, a hormone that stimulates uterine contractions and limits uterine bleeding after birth, is the standard of care for prevention of PPH during the third stage of labor Misoprostol, a synthetic prostaglandin with uterotonic properties, has been proposed as an alternative strategy for prevention of PPH in settings where oxytocin use is not feasible. It has important advantages over oxytocin, including the potential for oral administration and a long shelf life at room temperature We performed a double-blind, double-dummy randomized controlled non-inferiority trial comparing sublingual misoprostol versus oxytocin at a publically funded regional referral hospital in rural, southwestern Uganda. We aimed to elucidate the comparative benefit of oxytocin versus sublingual misoprostol, at the World Health Organization recommended dose of 600 µg This study was approved by the Institutional Review Committee of Mbarara University of Science and Technology and the Uganda National Council for Science and Technology. Trial registration at ClinicalTrials.gov (NCT01866241) was completed approximately halfway through the study. The delayed registration was due to the prolonged leave of the single ClinicalTrials.gov administrator at the principal investigator's institution.We conducted a double-blind, double-dummy randomized controlled non-inferiority trial at Mbarara Regional Referral Hospital, a publically funded teaching hospital in southwestern Uganda serving ten districts with a population of over 5 million people. The hospital employs seven obstetricians and 22 midwives. Hospital staff perform over 10,000 deliveries annually. Prior to the study, we performed a retrospective review of hospital records to estimate rates of attended births, PPH, and maternal mortality. During that review, we counted 9,027 births over a 10-mo period. During that period, 2,979 mothers (33%) were recorded to have had PPH, and 11 mothers died during admission because of complications of PPH (0.12% of mothers in the review period).Midwife research assistants (MRAs) screened laboring mothers in early active labor on arrival to the prenatal ward. Eligibility criteria were (1) age above 18 y, (2) 38–41 wk of amenorrhea, and (3) anticipated uncomplicated vaginal delivery as assessed by hospital staff. The exclusion criteria were (1) confirmed intrauterine fetal death, (2) self-reported maternal heart disease, (3) current diagnosis of severe malaria or acute bacterial infection, (4) multiple pregnancy, (5) induced or augmented labor, (6) elective cesarean section, (7) antepartum hemorrhage, (8) reported hypersensitivity to prostaglandins, and (9) altered cognitive status as assessed by MRA. MRAs obtained informed consent from all eligible participants after the birth was predicted to be an uncomplicated vaginal delivery. An MRA trained in human participant research conducted informed consent procedures with eligible mothers in the local language in a private area of the hospital. Only mothers in the early stages of labor (less than 6 cm dilation) were approached. All consenting participants gave written informed consent, or for those who could not write, a thumbprint was made on the consent form.A study biostatistician generated a randomization list with a block size of ten, totaling 570 participants in each group. The list was shared only with the study clinical pharmacist, who prepared the study drugs and placebos. Each participant received a treatment (600 µg of misoprostol or 10 IU of oxytocin) and placebo  within 1 min of birth. An independent clinical pharmacist at Mbarara University of Science and Technology prepared the corresponding treatments and placebos. Misoprostol 200-µg pills  were procured from Laborex Uganda. Oxytocin (10 IU/1 ml) was procured from Joint Medical Store . Before the use of the medications, we performed bioequivalence testing for both active interventions at the Ugandan National Chemotherapeutics Research Laboratory. Bioequivalence for misoprostol ranged from 95.8% to 99.8%, and for oxytocin ranged from 94.7% to 103.5%. To achieve blinding of the participants and assessors, both inactive agents were manufactured and packaged to resemble actual study medicines in terms of shape, size, and color by Kampala Pharmaceuticals Industries (Uganda).MRAs received opaque envelopes with affixed study codes, containing both an injection (1 ml of oxytocin 10 IU or its placebo) and three pills (misoprostol 600 µg or its placebo), which were given intramuscularly and sublingually, respectively, within 1 min of delivery. Delayed cord clamping was preferred, and the placenta was delivered by controlled cord traction or manually if not delivered within 30 min postpartum, as per Ugandan national clinical guidelines A blood sample for complete blood count was drawn immediately after admission and again prior to hospital discharge, or before blood transfusion. MRAs recorded vital signs, duration of second and third stages of labor, secondary use of open-label uterotonics, placental retention, requirement for blood transfusion, and side effects, using a standardized data collection form. After the baby was born, the amniotic fluid was drained immediately. A clean plastic sheet specifically designed and piloted to collect blood for this trial was placed under the mother's buttocks during and after the third stage of labor. Blood was drained into a calibrated container to improve accuracy in blood loss measurement Our primary outcome was primary PPH, defined as maternal loss of blood ≥500 ml within 24 h of birth, as conventionally defined NI). We selected the non-inferiority margin of 6% based on prior data comparing oxytocin with placebo for active management of labor that demonstrated a 50% relative reduction in the rate of PPH with oxytocin versus placebo p-values with chi-squared tests using a level of significance of 0.05. We also tested for the significance of absolute risk differences using the Z-test of proportions. For continuous outcomes, we estimated p-values using Student's t tests. All primary and secondary outcomes were analyzed using intention-to-treat analyses  2). Finally, although our study was fully randomized, we noted differences between treatment groups in the proportion of women with the following characteristics: presence of perineal tears, requirement for episiotomy, and parity. As such, we performed post hoc analyses to assess for confounding by fitting multivariable logistic regression models to assess for differences in our by-treatment estimates after adjustment for these characteristics. All statistical analyses were performed using STATA version 12.0 . An independent data safety monitoring board composed of members at the Mbarara University of Science and Technology, Makerere University, and Mbarara Regional Referral Hospital reviewed preliminary results at 50% (570) and 75% (855) of projected enrollment, as specified in the protocol, and recommended continuing study procedures.We followed CONSORT guidelines for conducting and reporting a non-inferiority study p<0.001; absolute risk difference 11.2%, 95% CI 6.44 to 16.1; Of 8,867 mothers screened for eligibility from 23 September 2012 to 9 September 2013, 4,314 were eligible. A total of 2,369 (55%) declined participation in the study , and 1,1p = 0.391; absolute risk difference 0.9%, 95% CI −1.12 to 2.88). There was also no difference in the rate of severe PPH between groups as estimated at 1 and 2 h postpartum. More mothers in the misoprostol group than in the oxytocin group received additional open-label oxytocin (p = 0.062). The number of mothers requiring and receiving a blood transfusion was higher in the oxytocin group than in the misoprostol group, but the difference did not reach statistical significance . There were also no significant differences in hemoglobin change (p = 0.075), mean postpartum hemoglobin (p = 0.074), rate of retained placenta (p = 0.378), or duration of the third stage of labor (p = 0.823) (We found a benefit for oxytocin versus misoprostol in terms of measured blood loss at 1 and 2 h postpartum . The mea= 0.823) .p<0.001).While we performed a randomized control trial and any differences in baseline characteristics occurred by chance, we did detect baseline differences in parity, requirement for episiotomy, and requirement for repair of perineal tears between study groups . We assep<0.001), nausea and vomiting , and temperature >37.5°C . Afterpains were more common in the oxytocin group than in the misoprostol group (p = 0.036). No differences were found between the misoprostol and oxytocin groups in the rates of diarrhea (p = 0.155) or headache (p = 0.829).Side effects were more common in the misoprostol group than in the oxytocin group. A greater proportion of women in the misoprostol group than in the oxytocin group experienced moderate to severe shivering  and an absolute risk increase of 11.2% with misoprostol versus oxytocin. We also found a 33% higher rate of severe PPH  in the misoprostol group, although this difference was not statistically significant. There were no maternal deaths in either group. The rates of secondary outcomes, including mean postpartum hemoglobin, requirement for additional uterotonics, hemoglobin changes, blood transfusion, duration of third stage of labor, and retained placenta were similar in both groups. While not statistically significant, we did observe a lower absolute rate of blood transfusion and proportion of women with postpartum hemoglobin <80 g/l in the misoprostol group.Our data contribute to a complex array of data on optimal prevention of PPH in the third stage of labor in resource-limited settings. Like many prior studies n = 100) specifically compared sublingual misoprostol at the routinely used dose of 600 µg to oxytocin at a dose of 10 IU, and found a lower mean blood loss with oxytocin n = 60) compared sublingual misoprostol 600 µg to syntometrine in place of oxytocin, and found no difference in PPH between the two groups Our results are largely consistent with prior studies comparing misoprostol with oxytocin for prevention of PPH. Only one prior trial , only 663 women received sublingual misoprostol, and only 60 women did so at the recommended dose of 600 µg While we acknowledge that a recent large systematic review comparing misoprostol with injectable uterotonics in the management of the third stage of labor has been conducted Importantly, and in contrast to our study, prior studies have demonstrated a significantly higher risk of both PPH (≥500 ml) and severe PPH  when oral misoprostol is used versus oxytocin Another potential explanation for differences between our study and prior data, which have shown larger effect sizes for differences between prostaglandins and oxytocin, is our exclusion of women with cesarean deliveries and multiple pregnancies. Our selection criteria could underestimate true differences in bleeding risk in the general population, and specifically in higher risk women.We found increased rates of side effects with misoprostol versus oxytocin, as has been previously reported The benefit of oxytocin over sublingual misoprostol for prevention of PPH in this trial was seen across most sub-groups. Effect sizes appeared smaller in certain sub-groups, for example, women with admission hemoglobin less than 120 g/l, those older than 35 y, those giving birth to infants with a birth weight less than 2,500 g, and those with parity greater than four, which corroborates prior work demonstrating increased risk of PPH with advanced maternal age, with anemia p = 0.003). We performed the study in a prototypical, publically funded and operated hospital in a rural setting with an active maternity unit, subject to the standard limitations of public sector health care facilities in the region. As such, the study has great potential for generalizability to similar settings.Our study had a number of strengths. All study investigators and clinical staff were blinded to treatment allocation. We used placebos for both oxytocin injection and misoprostol pills. Although blinding might have been unmasked, particularly by known side effects , we found similar benefit for oxytocin in a sub-analysis of women without documented shivering . A review of stated reasons for declining participation revealed that most (97%) participants who declined were disinterested in participating in a research study, which was perhaps not unexpected given that most women were presenting in active labor. A recent survey study on the ward  demonstrated that most mothers on the maternity ward in this hospital (92%) have little or no knowledge of medicines administered during labor. Nonetheless, the high declination rate might introduce a selection bias towards relatively healthy women.p = 0.391). There were also similar rates of changes in postpartum hemoglobin, duration of the third stage of labor, requirement for additional uterotonics, and requirement for a blood transfusion. These data demonstrate that, in settings where it is available, oxytocin should remain a preferred agent for prevention of PPH. However, sublingual misoprostol appears to maintain an important role for prevention of severe PPH and other complications of PPH where oxytocin is not available, and reinforces the array of available interventions for reducing maternal morbidity and mortality.We found that sublingual misoprostol 600 µg is inferior to oxytocin 10 IU for prevention of primary PPH during active management of the third stage of labor among women undergoing uncomplicated delivery in a rural referral hospital in southwestern Uganda. Severe PPH was rare in our study population, and we detected no significant difference between those receiving sublingual misoprostol versus oxytocin Click here for additional data file.Data S1Dataset.(CSV)Click here for additional data file.Text S1Trial protocol.(PDF)Click here for additional data file.


Trichophyton rubrum, an anthropophilic and cosmopolitan fungus, is the most common agent of superficial mycoses. In this study, T. rubrum infection was modelled by adding human skin sections to a limited medium containing glucose and cDNA microarrays were used to monitor T. rubrum gene expression patterns on a global level. We observed that exposure to human skin resulted in upregulation of the expression levels of T. rubrum genes related to many cellular and biological processes, including transcription and translation, metabolism and secondary transport, the stress response, and signalling pathways. These results provide a reference set of T. rubrum genes whose expression patterns change upon infection and reveal previously unknown genes that most likely correspond to proteins that should be considered as virulence factor candidates and potential new drug targets for T. rubrum infection. Trichophyton rubrum is a filamentous fungus found throughout the world that can infect human keratinized tissue , and is the causal agent of 80–90 % of all chronic and recurrent dermatophytoses . The results reveal a number of genes for which expression may be specifically regulated during infection, as well as genes related to virulence and adaptation, thereby suggesting new potential drug targets for the treatment of infections mediated by this pathogen.Previously, our group reported a sequencing program of over 40 000 expressed sequence tags (ESTs) derived from 10 different stages of the This study was approved by the Review Board of the Institute of Pathogen Biology. The skin samples used were collected from an abdominoplasty and were removed during the normal course of surgery. This was only done on the one occasion. Written informed consent was obtained from the patient who donated the skin sample.2 with full epidermal and dermal thickness, and the pieces were placed in small Petri dishes. The skin pieces were immersed in cold sterilized PBS. Whenever possible, the skin samples were used within 1 h of removal.The skin sections used in this study were collected from a woman who underwent an extended abdominoplasty. The normal thigh skin was incised into pieces measuring approximately 0.1–0.2 cmT. rubrum clinical isolate BMU01672 used throughout this study was obtained from a patient suffering from tinea unguium. The strain was confirmed as T. rubrum by morphological identification, as well as by PCR amplification and sequencing of the 18S rDNA and internal transcribed spacer regions. Strain reference samples were stored at −20 °C in the Research Centre for Medical Mycology, Beijing, PR China (The T. rubrum microconidia were isolated as reported previously and adjusted to a concentration of 5–8×108 conidia ml−1 and used as inoculum (5×106 conidia ml−1) in the following experiments 2HPO4, 6.6 g l−1; KH2PO4, 0.46 g l−1; KH2PO4·3H2O, 1.3 g l−1; MgSO4·7H2O, 0.49 g l−1], and incubated for 24 h. The aim of this incubation step was to eliminate the interference of the Sabouraud medium, which contained protein components that may have influenced gene expression. To analyse the gene expression of the clinical isolate under infection conditions, 2 g human skin sections were added to each of 12 flasks (250 ml), each with 80 ml LM. Another group of 12 flasks with an equal volume of LM but lacking the human skin sections was used as a control. Fungal mycelia (200 mg) were introduced into every flask and the flasks were then incubated at 28 °C with constant shaking. Three samples taken directly from the fungal mycelia were used as the 0 h samples. Subsequent samples were independently cultured, and harvested at 1, 3, 6 and 12 h.260. The quality of the total RNA was determined by capillary electrophoresis analysis using an Agilent 2100 Bioanalyser. Poly(A)+mRNA was isolated with the Oligotex mRNA Mini kit (Qiagen).At every time point, triplicate samples were collected from the two conditions (i.e. with and without skin). The mycelia were then ground into powder with a mortar and pestle in liquid nitrogen to facilitate cell disruption. Total RNA was isolated using the RNeasy Plant Mini kit (Qiagen) according to the manufacturer’s instructions. The RNA concentration was quantified by measurement of ODTest mRNA enriched from 50 µg total RNA was reverse transcribed into cDNA and labelled with the fluorescent dye Cy5. Additionally, reference genomic DNA (5 µg) isolated at the hyphal stage was labelled with Cy3  using TIGR MultiExperiment Viewer (MeV) software to identify the genes whose expression levels were altered significantly during the culturing process in skin suspension medium. To identify the genes whose expression levels were altered dramatically in response to human skin induction rather than in a time-dependent manner, ANOVA was also used to compare the differences in the expression pattern between T. rubrum cultured in suspension medium and LM (P<0.01). Finally, the changes in the expression levels of each significant gene were clustered using TIGR MultiExperiment Viewer (MeV) software and the k-means clustering (KMC) method.After hybridization, the slides were scanned using a GenePix 4000A microarray scanner (Axon Instruments) and the acquired microarray images were analysed using GenePix Pro 6.0 software. The data were filtered for spots fitting all of the following features: spot diameter ≥80 µm, % B (532 or 635)+2SD >55, SNR635 (or 532) ≥3. The filtered data were then normalized  by the GenePix Pro 6.0 software. The datasets were further normalized with a total intensity and Lowess normalization using TIGR T. rubrum database (http://www.mgc.ac.cn/TrED/).Microarray experimental design, hybridizations and data processing in this study complied with the Minimum Information About Microarray Experiment guidelines. All of the EST sequences used for cDNA microarray construction have been submitted to GenBank under accession numbers DW405580–DW407270 and DW678211–DW711189, and the GenBank accession numbers of ESTs corresponding to the positions on the cDNA microarray have been deposited in the Gene Expression Omnibus repository under the accession number GPL7240. The microarray data have been deposited in the Gene Expression Omnibus repository under the accession number GSE15532. Detailed information about the EST contig assemblies and EST annotations can be obtained from our Ct) above the background for each reaction was calculated. The Ct value of 18S rRNA was subtracted from that of the gene of interest to obtain a ΔCt value. The ΔCt value of an arbitrary calibrator (e.g. an untreated sample) was subtracted from the ΔCt value of each sample to obtain a ΔΔCt value. The gene expression level relative to the calibrator was expressed as 2−ΔΔCt.To verify the microarray results, the relative expression levels of 15 genes in the study were estimated by quantitative real-time RT-PCR. Aliquots of the RNA preparations from samples at each of the time points used in the microarray experiments were saved for quantitative real-time RT-PCR. Gene-specific primers were designed for the genes and the 18S rRNA using Primer Express software (Applied Biosystems) . PCRs were performed on an Applied Biosystems GeneAmp7000 sequence detection system. Changes in the fluorescence of SYBR Green I dye were monitored by GeneAmp7000 software and the threshold cycle  during this period. Using ANOVA (P<0.01) by TIGR MeV software . Most of these genes were in clusters I and IV, which exhibited induced expression from the zero time point and reached peak expression at 6 h.Three genes involved in the chitin metabolic process  and DW685106, which encodes the cell wall enzyme 1,3-β-glucanosyltransferase, were induced upon addition of human skin sections.Thirty-seven genes relative to protein metabolism were induced during incubation (Table S4), nine of which were potential secreted proteases or peptidases, such as aspartyl protease, serine-type peptidase, metallopeptidase and prolidase pepP, which are likely involved in proteolysis and related to pathogenicity .nidulans and Aspergillus fumigatus . Apart from one gene that belonged to cluster III, the other 47 genes belonged to clusters I, II and IV, which were overexpressed during the culturing process. In our analysis, two putative genes, DW678242 and DW680904, encoding homocitrate synthase and α-aminoadipate reductase involved in lysine biosynthesis, were induced throughout the infection process. As α-aminoadipate reductase is a key enzyme in the branched pathway for lysine and β-lactam biosynthesis of filamentous fungi, and impaired lysine biosynthesis can severely attenuate virulence in Aspergillus Methionine production is also essential for protein biosynthesis in micro-organisms. Our data indicate that the gene EL785855, which encodes aspartate semialdehyde dehydrogenase, was upregulated; this enzyme functions at the first branch point in the biosynthetic pathway through which bacteria, fungi and higher plants use aspartate to synthesize certain amino acids, including lysine and methionine.l-aminoadipate-semialdehyde dehydrogenase and dimethylallyl tryptophan synthase, were observed in cluster I. The ergot alkaloids are a family of indole-derived mycotoxins that have a variety of important biological activities . Among these genes, 14 of 19 genes related to the structure and assembly of chromatin, chromosome segregation and cell cycle control were induced. The expression level of genes related to transcription was also altered after the addition of human skin sections. Thirty-two genes were assigned to ‘transcription’ and 27 of them, grouped into clusters I or IV, were induced.Translation was also changed notably in response to the addition of human skin sections. In the infection process, the expression of 84 genes encoding proteins that functioned in ribosomal components or protein synthesis was modified (Table S7). These 84 genes were suppressed at the beginning, induced at 3 h and reached the highest expression levels at 6 h. Thirty-six genes were ribosomal components and 35 other genes belonged to cluster I. Forty-eight of the other 49 genes, including those encoding translation initiation factor 2, 3 and 4, translation elongation factor Tu, peptide chain release factor 1, tRNA synthetases, and factors involved in protein folding, were assigned to clusters I and IV, and were induced by human skin sections.T. rubrum pathogenicity (The expression of 60 genes related to transport was modified in response to the addition of human skin sections (Table S8). Thirty of these genes were assigned to cluster I, 17 of them were assigned to cluster II and 13 of them were assigned to cluster IV. Of these 60 genes, 12 upregulated genes were related to vesicle-mediated autophagy and exocytosis. Additionally, 12 genes encoding major facilitator superfamily transporter proteins, two genes encoding ATP-binding cassette transporters, and three genes encoding proteins involved in iron and copper transport were also induced. These transporter proteins have remarkably broad substrate specificity, and are able to transport a wide variety of natural and synthetic toxic products of either endogenous or exogenous origin . Three homologues of genes encoding secondary antioxidant enzymes belonging to the glutathione S-transferase family  were also identified.We observed changes in the expression of 14 genes encoding proteins with a known or putative role in the response to temperature shift or oxidative stress (Table S9). These proteins included two molecular co-chaperones associated with cellular responses to temperature shifts, HSP70 (DW681773) and HSP90 (DW693707); one superoxide dismutase (EL788295), and three novel cytochrome Aspergillus fumigatus and Candida albicans (T. rubrum infection requires further study.The signal transduction pathways are conserved and mediate adaptive changes in many fungi, including cellular development and morphogenesis (T. rubrum infection by adding human skin sections to LM containing glucose to monitor global T. rubrum gene expression patterns using cDNA microarrays. Our results reflect the adaptation that results from the interaction of T. rubrum with its human host. In host–pathogen interactions, the gene expression of the pathogen is modulated by signals from the host and understanding the resulting expression patterns may provide insight into the disease mechanism. The transcription profile monitoring revealed that the expression levels of genes related to many cellular and biological processes of T. rubrum were induced by the addition of human skin sections, including transcription and translation, metabolism and secondary transport, stress response, and signalling pathways. The cell cycle is the basic cellular process involved in cell division, polar construction, morphogenesis and adaptation to different environments. We observed that a number of genes associated with cell cycle events, including the assembly of chromatin, chromosome segregation and cell cycle control, were upregulated. The transcription of genes encoding certain ribosomal subunits and translation factors was also upregulated highly after the human skin sections were added. These results suggest that the expression of many genes changes dramatically as T. rubrum adapts to the presence of human skin sections.In this study, we modelled a et al., 2011; T. rubrum proteolytic enzymes has been observed and is thought to be involved in infection (T. rubrum cDNA microarray, pathogenic dermatophyte Arthroderma benhamiae and the molecular basis of keratin degradation in T. rubrum indicated that numerous genes encoding secreted proteases were induced in these two fungi (Staib et al., 2010; T. rubrum genes involved in the biosynthesis of various amino acids and in amino acid metabolism. In these pathways, lysine and methionine biosynthesis have been identified as contributors to virulence in many fungal pathogens (T. rubrum infection process. These pathways are non-existent or they function differently in animals and humans. We hypothesize that certain genes that encode enzymes involved in the key steps of these pathways are promising antifungal drug targets. Some genes and pathways involved in secondary metabolism, the response to stress and the transport of toxic components were also induced after the addition of human skin sections. These genes and related pathways may be involved in virulence and determining the sensitivity to fungicides and other antimycotic agents.The secretion of proteolytic enzymes by dermatophytes is a key factor in the invasion and utilization of the stratum corneum of the host (Grumbt nfection . Using aT. rubrum is a human-specific pathogenic fungus. Due to the lack of an animal model to study biological processes involved in T. rubrum infection, the functional analysis of T. rubrum described here will provide important information regarding its pathogenicity and virulence.


Adenopolyps patients have a three-fold higher risk of colon cancer over the general population, which increases to six-fold if the polyps are multiple and with lower survival among African American population. Currently, 6% of CRC can be ascribed to mutations in particular genes. Moreover, the optimal management of patients with colorectal adenopolyps depends on the accuracy of appropriate staging strategies because patients with similar colorectal adenocarcinoma architecture display heterogeneity in the course and outcome of the disease. Oxidative stress, due to an imbalance between reactive oxygen species (ROS) and antioxidant capacities as well as a disruption of redox signaling, causes a wide range of damage to DNA, proteins, and lipids which promote tumor formation.t-tests were utilized for the resulting data set.This study applied spectrophotometric, dinitrophenylhydrazone (DNPH) assay, two-dimensional gel electrophoresis, and western blot analyses to assess the levels of oxidatively modified proteins in 41 pairs of primary colorectal tissues including normal/surrounding, adenopolyps  and carcinoma. Analysis of variance (ANOVA) and Student’s P < 0.05) and over 36% higher in levels in adenocarcinomas (P < 0.05). In normal tissues and tubular, there were no significant differences between the two groups in levels of protein carbonyls. Differences in the levels of protein carbonyl expression within individual patient samples with different number of tumor cells were notably evident.Our data showed that the levels of reactive protein carbonyl groups significantly increased as colorectal adenopolyps progresses to malignancy. No significant differences were found in the levels of carbonyl proteins between gender samples analyzed. For African American patients, there were, relative to Caucasians, 10% higher levels of reactive carbonyls in proteins of tubulovillous tissue samples (Results suggested that oxidative stress could be involved in the modification of oxidatively carbonyl proteins in the precancer stages, leading to increased aggressiveness of colorectal polyps. Despite the recent advances achieved in early diagnosis and treatment, colorectal cancer (CRC) is one of the main causes of cancer related deaths worldwide . PreviouGenerally, oxidative stress promotes damage to cellular proteins, lipids, membranes and DNA, and plays a key role in the development of cancer. ROS disrupt redox homeostasis and promote tumor formation by initiating aberrant activation of signaling pathways that lead to tumorigenesis . ColonicThe chronic aggressive action on the colonic mucosa caused by oxygen-reactive species gives rise to a chronic inflammatory process that progressively modifies the normal architecture of the colonic epithelium which promotes the appearance of areas with increasing degrees of tissue dysplasia . The cloThe risk of developing adenopolyps type of CRC increases with advancing age and the levels of oxidative modified proteins, carbonyl contents that are usually used to measure ROS in cells, have been implicated to increase in a variety of disease processes, notably during aging. Given that the electron transport chains in the mitochondria and endoplasmic reticulum are most important sources of ROS in pre-neoplastic and cancer cells, they are metabolically active and require high levels of ATP to maintain their higher-than-normal proliferation rates . In thisTable 1).Forty one pairs of primary colorectal tumor tissues that were from the Southern Regional Cooperative Human Tissue Network which were previously obtained from patients that underwent surgical resections and 41 of these samples were colorectal adenopolyps, comprising of tubular, tubulovillous, villous, polypvillous and carcinomas, 41 of their normal/surrounding tissues. Of these 41 pairs tissue samples, 11 pairs were from African Americans and 27 pairs were from Caucasians and 3 pairs of the samples were demographic unknown. Seventeen pairs of the samples were obtained from men and 21 pairs of female with mean age of 55 ± 10 years  and the demographic characteristics of the patients were grouped based on the clinical diagnosis as displayed in l groups .All studies were implemented under protocols approved by Institutional Review Boards of Morehouse School of Medicine and the University of Alabama at Birmingham.The cytosolic fractions of the tissue samples were prepared by differential centrifugation using mitochondria/cytosol fractionation kits . Approximately 400 mg of each sample was cut into small pieces and placed in a 2 ml plastic tube on ice and washed twice with ice-cold phosphate-buffered saline (PBS). Each tissue sample was mildly homogenized in an ice-cold dounce tissue grinder and centrifuged at 700 × g for 5 min at 4°C. The supernatant was removed, and 1 ml of homogenizing buffer containing protease inhibitors was added. The sample was incubated on ice for 10 min and homogenized in an ice-cold Dounce tissue grinder, with about 50 - 60 passes. The homogenate was then transferred into a 1.5 ml microcentrifuge tube and centrifuged at 700 × g for 10 min at 4°C. The supernatant was collected, transferred to a fresh 1.5 ml microcentrifuge tube, and centrifuged at 10,000 × g for 30 min at 4°C. The supernatant, the cytosolic fraction, was collected. This fraction was treated with a 1% streptomycin sulfate solution for 15 min to remove DNA, which could react with DNPH and contribute to the reactive carbonyl level of homogenates. After incubation, samples were centrifuged at 13,000 × g for 15 min at room temperature. The supernatant, a DNA-free preparation was removed and saved for DNPH assay.A microplate DC protein assay (BioRad) was used to measure the protein contents of the samples. Each sample was analyzed in duplicate, and a pooled tissue sample was included in each plate to estimate the inter-assay coefficient of variation. A fraction of 5 µl of each sample and standard protein (BSA) was added to the well of a 96 wells microplate followed by adding 200 µl of reagent A and B as recommended by BioRad protocol. The plate was placed on the plate mixer and mixed for 5 sec, and then incubated at room temperature for 15 min. The absorbance at 750 nm was determined spectrophotometrically, the protein concentration of each homogenate was extrapolated from a standard curve. Samples of an extract of MCF7 cells, and a protein extract from a control cell line were included in each run as positive controls.−1·cm−1. To determine the stability of the samples, protein carbonyls were measured in a pooled tissue sample that was repeatedly frozen and thawed and there was no significant difference in protein . Th. Th12].  protein  14]..−1·cm−1.® West Pico chemiluminescent substrate. A DNPH-derivatized standard protein was used for estimation of molecular weight. Proteins that were oxidatively modified were identified by their appearance as bands in the lane containing the derivatized sample, but not in the lane containing the control. Blots were quantified using the relative optical density on the level of reactive carbonyl proteins using myImageAnalysis v 1.1, Thermo Scientist.In this study, to determine the number and relative mass of the DNPH derivatized proteins in the tissue samples, SDS-PAGE and Western blot immunoassays were performed using OxyBlot Protein Oxidation Detection Kits, (Millipore). Samples of DNPH-derivatized proteins were resolved on 10% SDS-polyacrylamide gels. As a control an underivatized sample of each cytosolic fraction was run along with DNPH-derivatized samples. The proteins were transferred to PVDF membranes blotted with rabbit anti-DNPH antibody and detected with a super-Singnalt-tests.Data were analyzed using analysis of variance (ANOVA) and Student’s To compare the extent of oxidative modification among normal, colorectal adenopolyps and carcinoma tissues, measurement of the reactive carbonyl groups as relates to the intensity of the oxidative stress is essential for better understanding of the etiopathogenic mechanisms of carcinogensis. Free radicals in biological systems generally lead to oxidative, post-translational modifications of proteins . ProteinFigure 1 displays schematic diagraph of ROS production and its adverse effect on macromolecules. MOM; mitochondria outer, MIM; mitochondria inner membrane, ROS; Reactive Oxygen Species, COXI; cytochrome oxydase I, SOD; superoxide dismutase.Figure 2 displays the data of the progressively increasing levels of carbonyl groups were observed in the derivatized lysates samples in the degree of disease advancement from tubular, tubulovillous, villous, polypvillous to adenocarcinomas.Figure 3(a) and Figure 3(b) display results from Western blots that showed a distinct difference in protein expression patterns between normal/surrounding, tubulovillous, villous and adenocarnoma tissues which were similar to those obtained with the spectrophotometric techniques. Lanes 1 and 3 are representatives of samples which were not DNPH-derivatized and used as negative controls for oxidized protein detection. DNPH are used as a marker for detection of oxidized protein and secondary antibody only detects the DNPH derivatized oxidized proteins. Relative to normal surrounding tissues, protein reactive carbonyls were elevated in adenopolyps tissues and notably, in the invasive stages and there were no significant differences were found in the levels of carbonyl proteins between gender samples analyzed.Figure 4 displays data on the different levels of reactive carbonyl group between tissue samples from African Americans and Caucasians. For African Americans, there were, relative to Caucasians, 10% higher levels of reactive carbonyls in proteins of tubulovillous tissue samples (P < 0.05) and over 36% higher in levels in adenocarcinomas (P < 0.05). In normal tissues and tubular, there were no significant differences between the two groups in levels of protein carbonyls.Figure 5(a) displays data that showed a 57%, 40%, and 54% higher levels of carbonyl protein in the tumors as compare to their normal surrounding tissues within respective three patients.Figure 5(b) displays data that indicated tissue samples with higher contents of tumor cells exhibited higher levels of oxidized proteins relative to normal surrounding tissues and to samples with fewer tumor cells from same patient; A 70% of higher levels of oxidized proteins was observed within individual patient samples with high degree of tumor cells relative to normal surrounding tissues as compare to samples with fewer degree of tumor cells.α and ROS activate nuclear factor kappa-B (NFκB). In its normal state, NFκB is inhibited by its inhibitory protein (IκBα), which downregulates the inflammatory response. In nuclei, NFκB induces the expression of genes involved in cell proliferation, apoptosis, and carcinogenesis [The risk of carcinogenesis and other age-related diseases has been associated with oxidized proteins (protein carbonyls)  16]-[20-[2016]- 5] 21] [21]5] [ [21]5] . ROS proogenesis  and alsoet al. ..47].Results from this study demonstrate an association of elevated levels of reactive protein carbonyls formed by oxidative stress, with colorectal adenopolyps. The results also indicate a racial difference in levels of these carbonyl groups and invasive stages of colorectal carcinoma among patients bearing this disease. Additional research is needed to determine if a higher prevalence of aggressive colorectal carcinomas in African Americans correlates with greater oxidative damage.