Nitro- and oxy-PAHs in grassland soils from decade-long sampling in central Europe.

Long-term exposure to polycyclic aromatic hydrocarbons (PAHs) and their nitrated (NPAHs) and oxygenated (OPAHs) derivatives can cause adverse health effects due to their carcinogenicity, mutagenicity and oxidative potential. The distribution of PAH derivatives in the terrestrial environment has hardly been studied, although several PAH derivatives are ubiquitous in air and long-lived in soil and water. We report the multi-annual variations in the concentrations of NPAHs, OPAHs and PAHs in soils sampled at a semi-urban (Mokrá, Czech Republic) and a regional background site (Kosetice, Czech Republic) in central Europe. The concentrations of the Σ18NPAHs and the Σ11+2OPAHs and O-heterocycles were 0.31 ± 0.23 ng g-1 and 4.03 ± 3.03 ng g-1, respectively, in Kosetice, while slightly higher concentrations of 0.54 ± 0.45 ng g-1 and 5.91 ± 0.45 ng g-1, respectively, were found in soil from Mokrá. Among the 5 NPAHs found in the soils, 1-nitropyrene and less so 6-nitrobenzo(a)pyrene were most abundant. The OPAHs were more evenly distributed. The ratios of the PAH derivatives to their parent PAHs in Kosetice indicate that they were long-range transported to the background site. Our results show that several NPAHs and OPAHs are abundant in soil and that gas-particle partitioning is a major factor influencing the concentration of several semi-volatile NPAHs and OPAHs in the soils. Complete understanding of the long-term variations of NPAH and OPAH concentrations in soil is limited by the lack of kinetic data describing their formation and degradation.

Predicting impacts of water conservation with a stochastic sewer model.

Population growth and climate change put a strain on water resources; hence, there are growing initiatives to reduce water use. Reducing household water use will likely reduce sewer input. This work demonstrates the use of a stochastic sewer model to quantify the effect water conservation has on sewer hydraulics and wastewater concentration. Probabilistic discharge patterns have been developed using SIMDEUM WW® and fed into hydraulic modelling software InfoWorks ICM® to produce likely flow and quality profiles for five future water use scenarios. The scenarios tested were developed to outline how commercial and political factors may change water use in future. Scenario testing revealed that 15-60% water reduction reflected a 1-48% drop in the morning peak flow. The water use reduction was predicted to increase wastewater concentrations of chemical oxygen demand (COD), total Kjeldahl nitrogen (TKN) and total phosphorus (TPH) by 55-180%, 19-116% and 30-206% respectively. The sewer flow model was developed, calibrated and validated using a case study in the Wessex Water region of the UK and all future scenarios were compared to the validated baseline case. This wastewater flow and quality model allows scenario testing, which could help redesign future sewer networks to better prepare for water conservation strategies.

Effects of phosphate addition on the removal of disinfection by-product formation potentials by biological activated carbon filtration.

In drinking water treatment plants (DWTPs), the widely used biological activated carbon filters (BACFs), as the last barrier before disinfection, can remove dissolved organic matter (DOM) known as precursors of disinfection by-products (DBPs). Whether phosphate addition can improve water purification and DBP control of BACFs is still controversial. This study investigated short-term and long-term effects of phosphate addition on controlling DBP formation potentials (FPs) by BACFs via column and batch experiments. The BAC columns presented good water purification performance: they removed around 50 % DOM, nearly all fulvic acid-likes and humic acid-likes as well as 5 %-70 % chlor(am)innated THM4, HAA9 and HAN4 FPs (except chloraminated THM4 FPs)， which was mainly contributed by aerobic bacteria not anoxic bacteria. Phosphate addition within 7-14 days further improved removals of DOM, aromatic organics, fluorescence fractions in DOM as well as HAA9 and HAN4 FPs (especially TCAA FP and TCAN FP) to different extent. However, this improvement did not last longer, and removals of DOM, aromatic organics, two fluorescence fractions (soluble microbial byproduct-likes and humic acid-likes) and DBP FPs decreased despite long-term phosphate addition. Oxic and anoxic batch experiments showed that the positive response of water purification to short-term phosphate addition was also mainly attributed to aerobic bacteria and not to anoxic bacteria. For example, the former decreased DOM and DBP FPs, while the latter increased protein- and tryptophan-like substances as well as chloraminated THM4 FPs. Phosphate addition resulted in EPS increase in anoxic reactors and decrease in oxic reactors. These results indicated that a high dissolved oxygen in BACFs may be helpful for water purification and DBP control. Overall, short-term phosphate addition into phosphorus-limited water is beneficial for BACFs to control DBPs while long-term addition has no effect. Therefore, an intermittent phosphate addition into BACFs is suggested to control DBPs in DWTPs.

Spatial and temporal distribution of the currently-used and recently-banned pesticides in arable soils of the Czech Republic.

This study presents monitoring data on the spatial and temporal occurrence of pesticide residues in arable soils of the Czech Republic and relates it to soil properties, pesticide usage and data on application provided by farmers. In total, 34 soils were sampled during 2014-2017, amounting to 136 samples which were analyzed for 60 pesticides and four transformation products. Conazole fungicides were frequently present in soils above the limit of quantification and/or above the 0.01 mg/kg threshold. Of the other pesticide types, the herbicides diflufenican, chlorotoluron, metolachlor, pendimethalin and terbuthylazine, fungicides azoxystrobin, carbendazim, fenpropidin, fenpropimorph and prochloraz and the insecticide methoxyfenozide were found in ≥20% of soils in at least one sampling campaign. Soils typically (>50%) contained 2-7 residues with a maximum of 14. For the 136 samples, 116 different mixtures were identified. The occurrence of pesticides was driven by their annual usage, their half-lives in soil, and their hydrophobicity. A comparison of the monitoring data and pesticide application data provided by farmers revealed that 63% of the applied pesticides are not likely to persist until the following growing season while up to 69% of pesticide residues found in soils could be inherited from the previous growing season(s).

Ensuring effective Essential Obstetric Care in resource poor settings.

Although Emergency Obstetric Care (EOC) is globally accepted as a key strategy to improve maternal health and reduce maternal mortality, there is still a lot of debate surrounding its use--What is EOC? Is it evidence-based? How can we measure it? How can we improve access to EOC? This paper attempts to answer these questions. Although there are no randomized controlled trials, there is strong evidence from quasi-experimental, observational and ecological studies that EOC should be a critical component of any programme to reduce maternal mortality. This paper also identifies the barriers to accessing EOC and proposes strategies to overcome them which could contribute to achieving Millennium Development Goal 5.

Toxicity of four nitrogen-heterocyclic polyaromatic hydrocarbons (NPAHs) to soil organisms.

The aims of this study were: (i) to investigate the toxicity of N-heterocyclic polyaromatic hydrocarbons (NPAHs) quinoline, acridine, phenazine, and 1,10-phenanthroline to the soil invertebrates Eisenia fetida, Enchytraeus crypticus, Folsomia candida, and Caenorhabditis elegans, (ii) to compare the toxicity of four NPAHs and the species sensitivity, and (iii) to discuss possible risks of these compounds in soils. Different toxicities were found for the tested NPAHs which might be partially explained by their structure and properties. Effect concentrations expressed as soil pore-water concentrations were related to log K(ow), which indicated narcosis as the most probable mode of toxic action. The species sensitivity decreased in the rank: springtails >enchytraeids=earthworms> nematodes. Predicted no-effect concentration (PNEC) values were calculated for all tested species giving values from 0.5 to 6.8 mg/kg. It is unlikely that there is a risk for soil organisms in natural soils where lower NPAHs concentrations are expected.

Laboratory versus field soil aging: Impact on DDE bioavailability and sorption.

Solid-phase microextraction (SPME), XAD, and the sequential supercritical fluid extraction (SFE) were used to assess the influence of aging of p,p'-DDE in a laboratory contaminated soil for up to 730 days. The end points determined were the freely dissolved concentration (Cfree) using SPME, the potentially bioaccessible fraction (FXAD, %) and the distribution of p,p'-DDE among fast, moderate, and slow desorbing soil sites determined by three sequentially stronger SFE conditions. Cfree and FXAD decreased during the first 35 days of aging by up to 40%. After this, no significant changes were observed up to the end of the aging experiment. The relative percentage of fast desorbing sites tended to exponentially decrease with aging, while the percentage of moderate and slow desorbing sites increased over time. These changes were most apparent within the first 90 days of aging, after which the relative distribution of p,p'-DDE among desorbing sites remained relatively constant. Significant correlations between SFE and XAD results demonstrated that the XAD method preferentially desorbed p,p'-DDE from fast and moderate desorbing sites and is capable of extracting the bioaccessible fraction. The distribution among desorbing sites, Cfree and FXAD values determined after different periods of laboratory aging were then compared to those measured for a field-contaminated soil where p,p'-DDE had resided for more than 40 years. Cfree, FXAD and SFE profiles measured for the field-aged p,p'-DDE were similar to those observed for p,p'-DDE aged in laboratory for between 35 and 90 days. These results suggest that aging in the laboratory must be carried out for periods of months if it is to approximate field aging.

Assessment of the biological and chemical availability of the freshly spiked and aged DDE in soil.

The study compared the ability of various chemical methods (XAD, ß-hydroxypropylcyclodextrin - HPCD) and solid phase micro-extraction (SPME)) to mimic earthworm uptake from two similar soils containing either spiked or aged p,p´-DDE, thus representing two extreme scenarios with regard to the length of pollutant-soil contact time and the way of contamination. The extent of bioaccumulation was assessed at fixed exposure periods (10 and 21 days) and at equilibrium derived from uptake curves by multiple-point comparison or kinetic modeling. The decision on the best chemical predictor of biological uptake differed. The degree of bioaccumulation at equilibrium was best predicted by XAD while HPCD rather reflected the extent of accumulation derived after 21 days when, however, steady-state was not reached for spiked p,p´-DDE. SPME seemed to underestimate the uptake of aged p,p´-DDE, probably of the fraction taken up via soil particles. Thus, the degree of predictability seems to be associated with the capability of the chemical method to mimic the complex earthworm uptake via skin and intestinal tract as well as with the quality of biological data where the insufficient length of exposure period appears to be the major concern.

Association between severe disease course and nephritis with Q222R polymorphism in DNAse I gene among lupus patients: An Argentine multicenter study.

UNLABELLED: Objetives: Systemic lupus erythematosus is a multifactorial autoimmune disease and the glomerulonephritis is one of the most severe complications, which leads to severe persistent proteinuria, chronic renal failure, and end-stage renal disease. This multicenter study investigated the genetic associations of a non-synonymous single-nucleotide polymorphism in DNase I with the risk of lupus and its influence on development of nephropathy in an Argentinean population. METHODS: Using the Polymerase chain reaction restriction fragment length polymorphism method, the Q222R (+2373A→G; Gln244Arg) DNase I polymorphism was studied in 156 systemic lupus erythematosus patients and 170 healthy controls. RESULTS: Although no significant association between Q222R polymorphism and the risk of systemic lupus erythematosus was found, the presence of the A allele was associated with an increased risk for the development of nephropathy (p=0.019, Odd Ratio=2.196, 95 % confidence interval [1.135-4.247]) and a worse disease course [moderate disease course: p=0.006, Odd Ratio=3.250, 95% confidence interval (1.401-7.539); severe disease course: p=0.040, Odd Ratio=2.339, 95% confidence interval (1.040-5.260)]. CONCLUSIONS: A better understanding of the genetic basis of systemic lupus erythematosus will help in the development of new and more effectives strategies for the treatment of the disease in the future.

Unusual ribosomal RNA gene organization in copepods of the genus Calanus.

Ribosomal RNA genes in the nuclear genomes of eukaryotes are generally found in tandemly repeated units encoding 18 S, 5.8 S and 28 S rRNA (in that order). 5 S rRNA genes typically lie outside these units, most often in tandem clusters coding exclusively for 5 S rRNA. Inclusion of 5 S genes within the 18 S-5.8 S-28 S repeat unit is known only for certain protozoa and fungi. Here we report that, in the copepod Calanus finmarchicus, single 5 S genes are included within many or all of the 18 S-5.8 S-28 S repeat units. Sequence analyses of regions cloned from two of these repeat units show that they indeed include 5 S genes (which are distal to 28 S genes) and that these are transcribed from opposite strands.

Detailed physical map and set of overlapping clones covering the genome of the archaebacterium Haloferax volcanii DS2.

An integrated approach of "bottom up" and "top down" mapping has produced a minimal set of overlapping cosmid clones covering 96% of the 4140 kilobase-pairs (kbp) Haloferax volcanii DS2 genome and a completely closed physical map. This genome is partitioned into five replicons: a 2920 kbp chromosome and four plasmids, of 690 kbp (pHV4), 442 kbp (pHV3), 86 kbp(pHV1) and 6.4 kbp (pHV2). A restriction map for six infrequently-cutting restriction enzymes was constructed, representing a total of 903 sites in the cloned DNA. We have placed the two ribosomal RNA operons, the genes for 7 S RNA and for RNaseP RNA and 22 protein-coding genes on the map. Restriction site frequencies show significant variation in different portions of the genome. The regions of high site density correspond to halobacterial satellite or FII DNA which includes two small regions of the chromosome, the plasmids pHV1 and pHV2, and half of pHV4, but not pHV3.

Early time sequence in pregnenolone metabolism to testosterone in homogenates of human and rat testis.

The time sequence of the metabolism of [4-14C] pregnenolone to testosterone in homogenates of human and rat testis was studied with special emphasis on the chain of events in the early 15 min of incubation. The incubations were performed at 32 C in the presence of NAD and a NADPH-generating system. The various intermediate steroids were separated by means of HPLC using a silica aliphatic diol column. Correction for procedural losses was performed by dual labeling. The present study confirms earlier reported results which showed that in the rat metabolism of pregnenolone to testosterone proceeds via the delta 4 pathway. However, this discloses for the first time that the conversion of pregnenolone proceeds very fast: progesterone, 17 alpha-hydroxyprogesterone, and 17 alpha-hydroxypregnenolone as the only important delta 5 intermediate, peak and decline again to almost undetectable levels within the first 15 min of incubation. Androstenedione and testosterone start to accumulate from 1 min on under the conditions used. In contrast, in the human testis, homogenates metabolism of pregnenolone to testosterone proceeds comparatively slowly and almost exclusively via the delta 5 intermediates dehydroepiandrosterone and androstenediol. Testosterone makes its appearance only after about 8 min of incubation. The data illustrate the importance of short-term incubations in evaluating the metabolism of steroids.

The sex pheromone precursor androsta-5,16-dien-3 beta-ol is a major early metabolite in in vitro pregnenolone metabolism in human testicular homogenates.

In an earlier report we described the early time sequence of the in vitro metabolism of [4-14C]pregnenolone ([4-14C]P5) to testosterone in homogenates of human and rat testes and demonstrated the appearance of mainly delta 5 (humans)- and delta 4 (rats)-steroids within minutes after starting the incubation. In this study strong evidence is presented for the substantial synthesis from P5 of the sex pheromone precursor androsta-5,16-dien-3 beta-ol (ADL) in human, but not rat, testicular homogenates. The 16-unsaturated C19 steroid ADL appeared after 1 min of incubation, and within 5 min reached values (17-23% of total radioactivity added as [4-14C]P5) comparable to those of the major delta 5-steroids 17 alpha-hydroxypregnenolone and dehydroepiandrosterone. Thus, in humans, as in boars, the sex attractant precursor ADL is a major early testicular metabolite of P5.

Maternal testosterone and fetal sex.

To investigate the influence of fetal sex on maternal testosterone levels throughout pregnancy, blood was sampled from 37 healthy pregnant women from week 14 until term and at 6 weeks postpartum. Testosterone concentrations were measured with a highly specific RIA after chromatographic purification. Mean (+/- SD) testosterone at the end of gestation was significantly higher compared to non-pregnant values (3.10 +/- 2.38 mM/l, n = 32 vs 1.14 +/- 1.06 nM/l, n = 35). It appeared that in women carrying a male fetus testosterone levels gradually increased during pregnancy up to 3.99 +/- 2.72 nM/l. In women carrying a female fetus the levels decreased after the first trimester from 2.44 nM/l to 1.80 nM/l. A statistically significant difference (P less than 0.01) existed in maternal testosterone concentrations between both groups during the second half of pregnancy.

The effect of oral contraceptive use and pregnancy on the daily rhythm of cortisol and cortisone.

The effect of oral contraceptives and of pregnancy on the daily rhythm of cortisol, and its metabolite cortisone in plasma and saliva has been investigated. In both conditions the total plasma cortisol levels were raised to the same extent, the mean values in saliva in the oral contraceptive users being intermediate between those in pregnancy and in the controls, particularly in the morning. Salivary cortisone levels were more related to salivary cortisol than to total plasma cortisone which exhibited a rather flat daily rhythm. There was a shift in peak values for salivary cortisol and cortisone towards late morning: this may be due to a delay in the daily activation of the hypothalamic-pituitary-adrenal axis in these patients.

PIP: The daily rhythm of plasma free cortisol and its metabolite cortisone in pregnancy or during oral contraceptive (OC) use was investigated in 10 pregnant women, 11 users of low-dose OCs, and 12 nonpregnant controls who were not using OCs. Radioimmunoassay was performed in the analysis of citric-acid stimulated saliva samples collected from 5 AM to midnight at 1-2-hour intervals and plasma samples were obtained from 10 women. Both pregnancy and OC use were found to produce significantly elevated levels of salivary cortisol and cortisone as well as a delay in the peak time of each hormone. The plasma analyses revealed significant increases in cortisol concentrations in both pregnant women and OC users, but plasma concentrations of cortisone increased only in pregnant women. Peak concentrations of salivary and total plasma cortisol were significantly higher in the first half of pregnancy, while cortisone was significantly higher during the second half of pregnancy. The shift in the peak of cortisone and cortisol values was from about 7 AM in control to 8 AM during pregnancy, with OC users in an intermediate position. Unexpectedly, the values for free plasma cortisol were normal during the afternoon but raised in saliva. It is postulated that the observed shifts in the peak time of the daily rhythm of cortisol and cortisone during pregnancy and OC use reflect an estrogen-induced increased synthesis of corticosteroid-binding globulin. Of interest would be a 24-hour measurement of these two hormones in saliva, free plasma, and total plasma.

Evaluation of a direct assay for atrial natriuretic peptide.

A direct radioimmunoassay for the assessment of human atrial natriuretic peptide (ANP) in plasma, using a highly specific antibody and a well-defined monoiodotyrosyl-tracer was developed and evaluated by concurrent application of an extraction method. Sensitivity was 13.4 pg/ml; intra- and interassay variations were 3.1 and 5.5%, respectively; recovery averaged 99%; normal values ranged from 15-111 pg/ml (mean +/- SD = 59 +/- 25 pg/ml, n = 41). The results, including the effect of exercise, of the two methods correlated well. Pooling ANP values in normal subjects and patients with congestive heart failure gave a good correlation (p less than 0.01). However, due to processes in unextracted plasma, in the lower range the results from the direct method were erratic. Velocity and duration of centrifugation changed the number of platelets, but no effect on ANP levels, whether assessed by the direct or by the extraction method, was observed. Although the direct method is considerably less laborious than the extracted method its lack of reliability disqualifies it for most purposes.

The influence of the calcium channel antagonist verapamil on histamine release from target cells.

The aim of the study was to investigate the influence of verapamil on anti-IgE induced histamine release from basophils isolated from the blood of 10 atopic asthma patients. The results of the investigations showed that verapamil in concentration of 10(-2)M - 10(-6)M significantly inhibits histamine release from basophils of asthmatic patients. The degree of inhibition of histamine secretion depends on the concentration of the drug. Our studies suggest that verapamil may be useful in combination with more conventional drugs in the treatment of asthmatic patients, particularly those with ischemic heart diseases or hypertonia.

The relation between magnesium, blood histamine level and eosinophilia in the acute stage of the allergic reactions in humans.

Investigation of magnesium, blood histamine level and eosinophilia were carried out on 28 bronchial asthma patients during the exacerbation of asthma and in asymptomatic period of the disease. Control group consisted of 30 healthy persons. It was found that during asthma attack in the patients with atopic asthma magnesium level in blood and erythrocytes decreased which is correlated to the rise in histamine level and the number of eosinophils in blood. This relationship was less marked in patients with non-atopic asthma. Results obtained are a further confirmation of the role of magnesium ions in the pathomechanism of immediate allergic reactions in humans and its participation in the immunological release of histamine.

Serum antitrypsin activity and alpha1 antitrypsin level in atopic bronchial asthma.

The aim of our investigations was to evaluate the behavior of the important proteolitic inhibitor--serum alpha1 antitrypsin in patients with atopic and non-atopic bronchial asthma. The inhibitor concentration was determined by means of the immunodiffusion method, and antitrypsin activity was evaluated using the synthetic substrate BAPNA. The investigations were carried out on 53 patients with bronchial asthma and on 13 healthy persons. It was found that in some patients with atopic asthma alpha1 antitrypsin level and antitrypsin activity were very low but this did not lower significantly the mean value of the whole group. The results presented suggest that a relative alpha1 antitrypsin deficiency, at least in some patients, can be considered as being one of the pathogenetic factors in atopic asthma. In addition, determination of serum antitrypsin activity may be of practical significance in differential diagnosis of bronchial spastic reactions of bacterial and allergic origins.

Blood histamine level and histamine content in the lung tissue in immediate immunological reactions in human and experimental animals.

The blood histamine level was determined in 66 patients with bronchial asthma and 25 guinea-pigs in whom the asthma attacks were induced by histamine or ovoalbumin inhalation after previous immunization of the animals. At the same time, histamine content of the lung tissue of the guinea-pigs was determined. It was found that in both humans and animals the level of blood histamine during immediate allergic reactions rises significantly. The extent of this rise depends on intensity of the reaction and time of determination. In asymptomatic period the blood histamine level did not differ from that of the control groups. Histamine concentration in the lung tissue of many of the animals increased during asthma attack but not in all cases was this increase correlated to the rise in blood histamine level. The reasons for these changes are discussed.