Diazepam and its metabolites in the mothers' and newborns' hair as a biomarker of prenatal exposure

Pregnant women are exposed to benzodiazepines for therapeutic purposes during gestation. The goal of this study was to evaluate prenatal exposure to benzodiazepines. Time of exposure during course of pregnancy is a significant aspect of fetal exposure to drugs. Benzodiazepine concentration assay in hair of mothers and newborns exposed prenatally to these drugs was performed in the studies. Development, validation and evaluation of benzodiazepine determination method in mothers and their newborns enables assessment of health risks for the child and implementation of adequate therapeutic procedures. We used A LC-ESI-MS/MS method that allowed determination of diazepam (the main benzodiazepine used by pregnant women was diazepam) and its metabolites (nordazepam, oxazepam) in hair of mothers and newborns. LOQ 10 pg/mg of hair was used in the study. Results: concentration of nordazepam was higher than parent drug (diazepam) and higher in newborns’ hair when compared to mothers’. The mean concentrations of diazepam in mothers’ hair were 31.6±36.0 and 34.1±42.4 pg/mg in the second and third trimester of pregnancy respectively. The mean concentration of diazepam in newborns’ hair was higher and reached levels of 53.3±36.5 pg/mg. The mean concentration of nordazepam in the mothers’ hair corresponding to the second and third trimester was 52.9±48.1 and 89.9±122.8 pg/mg, respectively. Nordazepam in the newborns’ hair was detected at the mean level of 108.1±144.2 pg/mg. It was concluded that diazepam and nordazepam are permanently incorporated into the hair structure. Presence of diazepam and its metabolites in newborn’s hair confirms that these benzodiazepines permeate placental barrier. Segmental analysis of mothers’ hair enabled the assessment of drug administration time. Diazepam and its metabolites determined in hair of newborns may serve as biomarkers of prenatal exposure to these drugs. The performed LC-MS/MS analysis was accurate enough to determine even low concentrations of benzodiazepines, at the level of few pg/mg of hair. Levels of diazepam detected in hair of newborns were higher than levels determined in mothers. This may confirm the fact, that fetus’s ability to metabolize diazepam is scarce. Nordazepam was found in higher concentrations in hair of newborns than in hair of mothers, which may suggest that it is cumulated in child’s organism. Other metabolites of diazepam - oxazepam and temazepam - were detected in very few cases, in low concentrations

Procjena izloženosti UV zračenju tijekom ljetnih mjeseci u Hrvatskoj s pomoću jednostavne približne formule

The Tropospheric Ultraviolet-Visible (TUV) model, version 4.2 developed by Madronich (2003) was usedto estimate the extent of ultraviolet (UV) exposure of general population in Croatia over the summer. Solarnoon values (13 h local time, CEST) of the ultraviolet index (UVI) for the period April to October 2004 were calculated for 61 cities in Croatia. The results showed that the risk of sunburn at 13 h local time inclear weather was high between April and September (UVI >7) and very high in July (UVI >10). In July, the UVI exceeded 8 between 11 h and 15 h local time. In this study, we developed a simple approximate formula to estimate UVI. The formula includes data on the time, date, altitude and clouds. The difference between our estimate and the TUV model for the summer months of June, July and August at 10 h to16 h local time was less than 10 %.Tropospheric Ultraviolet-Visible (TUV) model, verzija 4.2 autora S. Madronicha (2003.) upotrijebljen je zaprocjenu izloženosti ultraljubičastom (UV) zračenju stanovništva u Hrvatskoj. Podnevne vrijednosti (13 hprema lokalnom vremenu) ultraljubičastog indeksa (UVI) izračunane su za 61 mjesto u Hrvatskoj za razdobljetravanj - listopad. Rezultati pokazuju da je u 13 h prema lokalnom vremenu rizik od nastanka opeklina izazvanih sunčevim zračenjem u danima bez naoblake visok između travnja i rujna (UVI > 7) te da je rizikvrlo visok tijekom srpnja (UVI >10). U srpnju tijekom dana UV indeks prelazi vrijednost 8 između 11 h i15 h prema lokalnom vremenu. U ovom radu za procjenu UV indeksa razvijena je jednostavna približna formula. Formula omogućava procjenu UV indeksa na temelju podataka o datumu, satu, nadmorskoj visini i naoblaci. Prilikom usporedbe rezultata dobivenih formulom i točnih rezultata dobivenih TUV modelom za ljetne mjesece lipanj, srpanj i kolovoz te razdoblje od 10 h do 16 h među rezultatima dobivena je razlikamanja od 10 %

Extreme events in total ozone over the Northern mid-latitudes: an analysis based on long-term data sets from five European ground-based stations

We apply methods from extreme value theory to identify extreme events in high (termed EHOs) and low (termed ELOs) total ozone and to describe the distribution tails (i.e. very high and very low values) of five long-term European ground-based total ozone time series. The influence of these extreme events on observed mean values, long-term trends and changes is analysed. The results show a decrease in EHOs and an increase in ELOs during the last decades, and establish that the observed downward trend in column ozone during the 1970-1990s is strongly dominated by changes in the frequency of extreme events. Furthermore, it is shown that clear 'fingerprints' of atmospheric dynamics (NAO, ENSO) and chemistry [ozone depleting substances (ODSs), polar vortex ozone loss] can be found in the frequency distribution of ozone extremes, even if no attribution is possible from standard metrics (e.g. annual mean values). The analysis complements earlier analysis for the world's longest total ozone record at Arosa, Switzerland, confirming and revealing the strong influence of atmospheric dynamics on observed ozone changes. The results provide clear evidence that in addition to ODS, volcanic eruptions and strong/moderate ENSO and NAO events had significant influence on column ozone in the European sector

Development of easy and effective real-time PCR tests to identify bovine, porcine, and ovine components in food

Proste, skuteczne i czułe metody identyfikacji gatunkowej komponentów mięsnych w produktach spożywczych są ważnym aspektem produkcji żywności. Są one istotne zarówno dla producentów, jak i konsumentów, którzy są coraz bardziej zainteresowani rzeczywistym składem żywności. W identyfikacji komponentów pochodzenia zwierzęcego w żywności największe znaczenie mają obecnie metody polegające na analizie mtDNA, co wynika ze znacznej trwałości oraz specyficzności gatunkowej tej cząsteczki. Celem pracy było opracowanie prostych i skutecznych testów identyfikacji gatunkowej komponentów bydlęcych, wieprzowych i owczych, przydatnych do analizy żywności. Badaniom poddano próbki mięsa o zawartości [%]: 6, 35, 60, 80 i 100 wołowiny w wieprzowinie, wieprzowiny w wołowinie i baraniny w wieprzowinie. Metoda polega na identyfikacji gatunkowo specyficznych dla bydła, świń i owiec fragmentów genu kodującego COX1 o długościach 68 pz oraz 53 pz. W opracowanych testach granica wykrywalności komponentu wieprzowego wynosiła 0,07 %, bydlęcego – 0,4 % i owczego – 0,5 %. Uzyskane wyniki wskazują na specyficzność gatunkową stosowanych testów. Reaktywność krzyżowa albo nie zachodzi, albo można ją zaobserwować w późnych cyklach reakcji. Metoda ma zastosowanie zarówno do mięsa surowego, jak i jego przetworów, takich jak kiełbasa, mielonka, szynka. Metoda nie jest czasochłonna (4 h), natomiast jest powtarzalna (względne odchylenie standardowe w przypadku mięsa surowego wynosi ≤ 1,57 %) oraz dokładna (błąd pomiaru ≤ 2,33). W analizach mięsa przetworzonego dokładność pomiaru jest mniejsza, a rozrzut wyników nieznacznie większy, co może wskazywać na konieczność dostosowania krzywej standardowej do próbek badanych pod względem przetworzenia.Simple, effective, and sensitive methods to species identify meat components in food products are an important aspect in the production of food production. They are essential for both the manufacturers and the consumers, who are more and more interested in the actual composition of foods. At present, among the most important methods to identify components of animal origin in food are those based on an mtDNA analysis owing to the considerable stability and species-specificity of that molecule. The objective of the research study was to develop simple and efficient tests for species identification of bovine, porcine, and ovine components, which would be useful for the analysis of food. The analysis covered samples of meat containing 6 %, 35 %, 60 %, 80 %, and 100 % of beef in pork, pork in beef, and mutton in pork. The method is based on the identification of cattle, pigs, and sheep species-specific fragments of the gene encoding COX1 with 68 and 53 bp. For the tests being developed, the limit of detection was 0.07 % as for the porcine component, 0.4 % as for the bovine component, and 0.5 % as for the ovine component. The results obtained show the species specificity of the tests applied. The cross reactivity does not occur or it can be found in the late cycles of reaction. This method may be applied to raw meat and to its products, such as sausages, luncheon meat, ham. The method is not time-consuming (4 hours); it is repeatable (relative standard deviation for raw meat ≤ 1.57 %) and accurate (measurement error ≤ 2.33 %). As for the analysis of the processed meat, the accuracy of measurement is lower, and the relative dispersion of results is slightly higher; this might indicate the need to adjust the standard curve to the samples the processing of which is to be analyzed

Long-term variations of the UV-B radiation over Central Europe as derived from the reconstructed UV time series

The daily doses of the erythemally weighted UV radiation are reconstructed for three sites in Central Europe: Belsk-Poland (1966–2001), Hradec Kralove-Czech Republic (1964–2001), and Tõravere-Estonia (1967–2001) to discuss the UV climatology and the long-term changes of the UV-B radiation since the mid 1960s. Various reconstruction models are examined: a purely statistical model based on the Multivariate Adaptive Regression Splines (MARS) methodology, and a hybrid model combining radiative transfer model calculations with empirical estimates of the cloud effects on the UV radiation. Modeled long-term variations of the surface UV doses appear to be in a reasonable agreement with the observed ones. A simple quality control procedure is proposed to check the homogeneity of the biometer and pyranometer data. The models are verified using the results of UV observations carried out at Belsk since 1976. MARS provides the best estimates of the UV doses, giving a mean difference between the modeled and observed monthly means equal to 0.6±2.5%. The basic findings are: similar climatological forcing by clouds for all considered stations (~30% reduction in the surface UV), long-term variations in UV monthly doses having the same temporal pattern for all stations with extreme low monthly values (~5% below overall mean level) at the end of the 1970s and extreme high monthly values (~5% above overall mean level) in the mid 1990s, regional peculiarities in the cloud long-term forcing sometimes leading to extended periods with elevated UV doses, recent stabilization of the ozone induced UV long-term changes being a response to a trendless tendency of total ozone since the mid 1990s. In the case of the slowdown of the total ozone trend over Northern Hemisphere mid-latitudes it seems that clouds will appear as the most important modulator of the UV radiation both in long- and short-time scales over next decades. Key words. Atmospheric composition and structure (biospheric-atmosphere interaction) – Meteorology and atmospheric dynamics (climatology; radiative processes

Downward surface flux computations in a vertically inhomogeneous grey planetary atmosphere Cálculo do fluxo radiativo superficial em uma atmosfera planetária cinza e verticalmente não-homogênea

We describe an efficient computational scheme for downward surface flux computations in a vertically inhomogeneous grey planetary atmosphere for different values of solar zenith angle. We start with the basic equations of a recently developed discrete ordinates spectral nodal method, and we derive suitable bidirectional functions whose diffuse components do not depend on the solar zenith angle. We then make use of these bidirectional functions to construct an efficient scheme for computing the downward surface fluxes in a given model atmosphere for a number of solar zenith angles. We illustrate the merit of the computational scheme described here with downward surface flux computations in a three-layer grey model atmosphere for four values of solar zenith angle, and we conclude this article with general remarks and directions for future work.<br>Este artigo descreve um esquema computacional baseado em desenvolvimentos recentes do método espectro-nodal de ordenadas discretas para o cálculo eficiente do fluxo radiativo superficial em uma atmosfera planetária cinza e verticalmente não-homogênea para valores distintos do ângulo zenital solar. A partir das equações básicas do método espectro-nodal de ordenadas discretas, são obtidas funções bidirecionais discretas cujas componentes difusas não dependem do ângulo zenital solar. Com essas funções bidirecionais discretas, é construído um esquema computacional para calcular eficientemente fluxos radiativos superficiais em uma dada atmosfera-modelo para vários ângulos zenitais solares. O mérito computacional do esquema resultante é ilustrado com resultados numéricos para os fluxos radiativos superficiais em uma atmosfera-modelo cinza com três camadas para quatro valores distintos do ângulo zenital solar. Este artigo é finalizado com observações gerais e indicações de trabalhos futuros

The effect of ozone and aerosols on the surface erythemal UV radiation estimated from OMI measurements

Surface erythemal UV radiation is mainly affected by total column ozone, aerosols, clouds, and solar zenith angle. The effect of ozone on the surface UV radiation has been explored many times in the previous studies due to the decrease of ozone layer. In this study, we calculated the effect of aerosols on the surface UV radiation as well as that of ozone using data acquired from Ozone Monitoring Instrument (OMI). First, ozone, aerosol optical depth (AOD), and surface erythemal UVB radiation measured from satellite are compared with those from ground measurements. The results showed that the comparison for ozone was good with r (2) of 0.92. For aerosol, there was difference between satellite measurements and surface measurements due to the insufficient information on aerosol in the retrieval algorithm. The r (2) for surface erythemal UV radiation was high (similar to 0.94) but satellite measurements showed about 30% larger values than surface measurements on average by not considering the effect of absorbing aerosols in the retrieval process from satellite measurements. Radiative amplification factor (RAF) is used to access the effect of ozone and aerosol quantitatively. RAF for ozone was 0.97 similar to 1.49 with solar zenith angle. To evaluate the effect of aerosol on the surface UV radiation, only clear-sky pixel data were used and solar zenith angle and total column amount of ozone were fixed. Also, RAF for aerosol was assessed according to the single scattering albedo (SSA) of aerosols. The results showed that RAF for aerosol with smaller SSA ( 0.90). The RAF for aerosol was 0.09 similar to 0.22 for the given conditions which was relatively small compared to that for ozone. However, considering the fact that aerosol optical depth can change largely in time and space while the total column amount of ozone does not change very much, it needs to include the effect of aerosol to predict the variations of surface UV radiation more correctly.close3