Plasma levels of apolipoprotein-E in residents of the European North of Russia

Background: Apolipoprotein-E (apoE) is one of the metabolically active apoproteins and plays an important role in lipid metabolism. However, there are no data on levels of apoE in residents of the North in spite of the fact that specific features of lipid metabolism in the northerners are described. The present work was designed to study plasma levels of apoE in residents of the European North of Russia. Methods: A total of 937 native residents of the European North of Russia (463 men and 474 women) aged 13–60 years were included in the study. ApoE concentrations in the blood plasma were measured by immunoturbidimetric method. Results: Plasma levels of apoE in residents of the European North of Russia were low. ApoE concentrations below the defined normal values were detected in 57.0% of the men and in 59.2% of the women. The mean plasma levels of apoE did not significantly differ in men and women (2.80 mg/dl vs 2.87 mg/dl). Plasma apoE concentrations in residents of the European North of Russia changed with age. Plasma levels of apoE decreased from 13 to 21 years in men and from 13 to 35 years in women and then increased in both sexes (p < 0.001). Conclusion: The limits of variation of plasma apoE levels in residents of the European North of Russia shift towards lower values. Plasma levels of apoE below normal values were observed in approximately half of investigation subjects

An analysis of diversity in agricultural land use in Oregon

An index suitable for measurement of the diversity of agricultural land use is developed. This index is based on a principle of measuring the deviation of a distribution from an even distribution and is similar to indexes employed to measure diversity in manufacturing The index is applied to the thirty-six Oregon counties, using land use data from the 1964 Census of Agriculture. The association of diversity, as measured by the index, with several physical and cultural variables in Oregon counties is then evaluated

Effect of Smoking Behavior before and during Pregnancy on Selected Birth Outcomes among Singleton Full-Term Pregnancy: A Murmansk County Birth Registry Study

Source at https://doi.org/10.3390/ijerph14080867 .The aim of our study was to assess associations between smoking behavior before and during pregnancy and selected adverse birth outcomes. This study is based on the Murmansk County Birth Registry (MCBR). Our study includes women who delivered a singleton pregnancy after 37 weeks of gestation (N = 44,486). Smoking information was self-reported and assessed at the first antenatal visit during pregnancy. We adjusted for potential confounders using logistic regression. The highest proportion of infants with low values of birth weight, birth length, head circumference, ponderal index and of the Apgar score at 5 min was observed for women who smoked both before and during pregnancy. We observed a dose-response relationship between the number of cigarettes smoked per day during pregnancy and the odds of the aforementioned adverse birth outcomes; neither were there significant differences in their occurrences among non-smokers and those who smoked before but not during pregnancy. Moreover, smoking reduction during pregnancy relative to its pre-gestation level did not influence the odds of the adverse birth outcomes. Our findings emphasize a continued need for action against tobacco smoking during pregnancy

Proton tracking in a high-granularity Digital Tracking Calorimeter for proton CT purposes

Radiation therapy with protons as of today utilizes information from x-ray CT in order to estimate the proton stopping power of the traversed tissue in a patient. The conversion from x-ray attenuation to proton stopping power in tissue introduces range uncertainties of the order of 2-3% of the range, uncertainties that are contributing to an increase of the necessary planning margins added to the target volume in a patient. Imaging methods and modalities, such as Dual Energy CT and proton CT, have come into consideration in the pursuit of obtaining an as good as possible estimate of the proton stopping power. In this study, a Digital Tracking Calorimeter is benchmarked for proof-of-concept for proton CT purposes. The Digital Tracking Calorimeteris applied for reconstruction of the tracks and energies of individual high energy protons. The presented prototype forms the basis for a proton CT system using a single technology for tracking and calorimetry. This advantage simplifies the setup and reduces the cost of a proton CT system assembly, and it is a unique feature of the Digital Tracking Calorimeter. Data from the AGORFIRM beamline at KVI-CART in Groningen in the Netherlands and Monte Carlo simulation results are used to in order to develop a tracking algorithm for the estimation of the residual ranges of a high number of concurrent proton tracks. The range of the individual protons can at present be estimated with a resolution of 4%. The readout system for this prototype is able to handle an effective proton frequency of 1 MHz by using 500 concurrent proton tracks in each readout frame, which is at the high end range of present similar prototypes. A future further optimized prototype will enable a high-speed and more accurate determination of the ranges of individual protons in a therapeutic beam.Comment: 21 pages, 8 figure

Risk factors for perinatal mortality in Murmansk County, Russia: a registry-based study

Source at http://dx.doi.org/10.1080/16549716.2017.1270536 Background: Factors contributing to perinatalmortality (PM) in Northwest Russia remain unclear. This study investigated possible associations between selected maternal and fetal characteristics and PM based on data from the population-based Murmansk County Birth Registry. Objective: This study investigated possible associations between selected maternal and fetal characteristics and PM based on data from the population-based Murmansk County Birth Registry. Methods: The study population consisted of all live- and stillbirths registered in the Murmansk County Birth Registry during 2006–2011 (n = 52,806). We excluded multiple births, births prior to 22 and after 45 completed weeks of gestation, infants with congenital malformations, and births with missing information regarding gestational age (a total of n = 3,666) and/or the studied characteristics (n = 2,356). Possible associations between maternal socio-demographic and lifestyle characteristics, maternal pre-pregnancy characteristics, pregnancy characteristics, and PM were studied by multivariable logistic regression. Crude and adjusted odds ratios with 95% confidence intervals were calculated. Results: Of the 49,140 births eligible for prevalence analysis, 338 were identified as perinatal deaths (6.9 per 1,000 births). After adjustment for other factors, maternal low education level, prior preterm delivery, spontaneous or induced abortions, antepartum hemorrhage, antenatally detected or suspected fetal growth retardation, and alcohol abuse during pregnancy all significantly increased the risk of PM. We observed a higher risk of PM in unmarried women, as well as overweight or obese mothers. Maternal underweight reduced the risk of PM. Conclusions: Our results suggest that both social and medical factors are important correlates of perinatal mortality in Northwest Russia

Photodiode read-out of the ALICE photon spectrometer PbWO4PbWO_{4} crystals

Proposal of abstract for LEB99, Snowmass, Colorado, 20-24 September 1999The PHOton Spectrometer of the ALICE experiment is an electromagnetic calorimeter of high granularity consisting of 17280 lead-tungstate (PWO) crystals of dimensions 22x22x180 mm3, read out by large-area PIN-diodes with very low-noise front-end electronics. The crystal assembly is operated at -25C to increase the PWO light yield. A 16.1x17.1 mm2 photodiode, optimized for the PWO emissio spectrum at 400-500 nm, has been developed. The 20x20 mm2 preamplifier PCB is attached to the back side of the diode ceramic frame. The charge sensitive preamplifier is built in discrete logic with two input JFETs for optimum matching with the ~150pF PIN-diode. A prototype shaper has been designed and built in discrete logic. For a detector matrix of 64 units the measured ENCs are between 450-550e at -25C. Beam tests demonstrate that the required energy resolution is reached.Summary:The PHOton Spectrometer of the ALICE experiment is an electromagnetic calorimeter of high granularity consisting of 17280 lead-tungstate (PWO) crystals of dimensions 22x22x180 mm3, coupled to large-area PIN-diodes with matching low-noise preamplifiers. PHOS is optimized for measuring photons, pi0s and eta mesons in the momentum ranges 0.5-10, 1-10 and 2-10 GeV/c, respectively, and is designed for the expected large number of particles that will be produced in central Pb-Pb collisions. Lead tungstate (PWO) is a fast scintillating crystal with a rather complex emission spectrum, consisting of two components: a blue component peaking at 420 nm and a green component peaking at 480-520 nm. The light yield of PWO at room temperature is low compared with other heavy scintillating crystals, for instance BGO. However, the yield depends strongly on the temperature with a coefficient of ~-2 degree. At the selected operating temperature of -25C the yield is about a factor of 3 higher compared to room temperature. Still, in order to reach the required energy resolution for a PHOS channel, an ENC noise of less than 600e for the PIN-diode-preamplifier-shaper stage is required. This is a very low value taking into account the high capacitance of 150-200 pF of the large area PIN-diodes. In collaboration with the PHOS project, the company AME (Horten, Norway) has designed and produced a PIN-photodiode optimized for the cross-section and spectral responsivity of the PHOS PWO crystal. The photodiode has an active area of 17.1x16.1 mm2 and is fabricated on n-type silicon material of thickness 280 um. The wafer specific resistivity is between 3000 and 6000 ohm-cm, which corresponds to a depletion voltage of 70V. The photodiode response is optimized for the spectral region 400-500 nm in order to match the PWO emission spectrum. The PIN-diode is mounted on a ceramic substrate 0.65 mm thick. On this substrate the diode is surrounded by a ceramic frame. The preamplifier PCB of dimension 20x20 mm2 is attached to the back side of the frame. The PIN-diode and bondings to ground and preamplifier input are protected by an optically transparent epoxy layer. The front side of the PIN-diode is glued onto the endface of the PWO crystal with optically transparent glue (Melt-Mount Quick-Stick, Cargille Laboratories, USA). Each crystal is wrapped in White Tyvek to ensure maximum light collection efficiency and optical insulation between the crystals. The PHOS detector consists of four independent modules, each with 4320 channels. The crystal assembly with the photo detectors are operated at -25 +/- 0.3C. The power dissipation per module is ~1 kW. The charge sensitive preamplifier is an operational amplifier built in discrete logic and with two input JFETs (BF861A). Using two JFETs in parallel gives the lowest noise for detector capacitance &gt;100 pF. A prototype shaper, comprising three amplification stages, has been designed and built in discrete logic. For a PIN-diode with capacitance ~150 pF and a leakage current &lt;1 nA under cooling, calculations give optimum time differentiation and integration constants around 3 microsec. For a detector matrix of 64 units the measured ENCs are between 450-550 e at -25C. Beam tests of this matrix show that the required energy resolution for the PHOS is reached

Assessing the relationship between perfluoroalkyl substances, thyroid hormones and binding proteins in pregnant women; a longitudinal mixed effects approach

Accepted manuscript version. Published version available at https://doi.org/10.1016/j.envint.2015.01.007. Accepted manuscript version, licensed CC BY-NC-ND 4.0.The mechanisms involved in thyroid homeostasis are complex, and perfluoroalkyl substances (PFASs) have been indicated to interfere at several levels in this endocrine system. Disruption of the maternal thyroid homeostasis during early pregnancy is of particular concern, where subclinical changes in maternal thyroid hormones (THs) may affect embryonic and foetal development. The present study investigated associations between THs, thyroid binding proteins (TH-BPs) and PFAS concentrations in pregnant women from Northern Norway. Women participating in The Northern Norway Mother-and-Child contaminant Cohort Study (MISA) donated a blood sample at three visits related to their pregnancy and postpartum period (during the second trimester, 3 days and 6 weeks after delivery) in the period 2007–2009. Participants were assigned to quartiles according to PFAS concentrations during the second trimester and mixed effects linear models were used to investigate potential associations between PFASs and repeated measurements of THs, TH-BPs, thyroxin binding capacity and thyroid peroxidase antibodies (anti-TPOs). Women within the highest perfluorooctane sulfonate (PFOS) quartile had 24% higher mean concentrations of thyroid stimulating hormone (TSH) compared to the first quartile at all sampling points. Women within the highest quartiles of perfluorodecanoate (PFDA) had 4% lower mean concentrations of triiodothyronine (T3) and women within the highest quartile of perfluoroundecanoate (PFUnDA) had 3% lower mean concentrations of free triiodothyronine (FT3). Further, the difference in concentrations and the changes between three time points were the same for the PFAS quartiles. Thyroxin binding capacity was associated with all the THs and TH-BPs, and was selected as a holistic adjustment for individual changes in TH homeostasis during pregnancy. Finally, adjusting for maternal iodine status did not influence the model predictions. Findings in the present study suggest modifications of TH homeostasis by PFASs in a background exposed maternal population. The variation in levels of THs between PFAS quartiles was within normal reference ranges and may not be of clinical significance in the pregnant woman. However, subtle individual changes in maternal THs may have significant consequences for foetal health

Prenatal exposure to persistent organic pollutants and child overweight/obesity at 5-year follow-up: a prospective cohort study

Source at https://doi.org/10.1186/s12940-017-0338-x .Background Prenatal exposure to persistent organic pollutants (POPs), may influence offspring weight gain. More prospective epidemiological studies are needed to compliment the growing body of evidence from animal studies. Methods Serum from 412 pregnant Norwegian and Swedish women participating in a Scandinavian prospective cohort study were collected in 1986–88, and analyses of two perfluoroalkyl substances (PFASs) and five organochlorines (OCs) were conducted. We used linear and logistic regression models with 95% confidence intervals (CIs) to evaluate the associations between maternal serum POP concentrations at 17–20 weeks of gestation and child overweight/obesity (body mass index (BMI) ≥ 85th percentile) at 5-year follow-up. Results were further stratified by country after testing for effect modification. We also assessed potential non-monotonic dose-response (NMDR) relationships. Results In adjusted linear models, we observed increased BMI-for-age-and-sex z-score (β = 0.18, 95% CI: 0.01–0.35), and increased triceps skinfold z-score (β = 0.15, 95% CI: 0.02–0.27) in children at 5-year follow-up per ln-unit increase in maternal serum perfluorooctane sulfonate (PFOS) concentrations. We observed increased odds for child overweight/obesity (BMI ≥ 85th percentile) for each ln-unit increase in maternal serum PFOS levels (adjusted OR: 2.04, 95% CI: 1.11–3.74), with stronger odds among Norwegian children (OR: 2.96, 95% CI: 1.42–6.15). We found similar associations between maternal serum perfluorooctanoate (PFOA) concentrations and child overweight/obesity. We found indications of NMDR relationships between PFOS and polychlorinated biphenyl (PCB) 153 and child overweight/obesity among Swedish children. Conclusion We found positive associations between maternal serum PFAS concentrations and child overweight/obesity at 5-year follow-up, particularly among Norwegian participants. We observed some evidence for NMDR relationships among Swedish participants

Persistent Organic Pollutants and the Association with Maternal and Infant Thyroid Homeostasis: A Multipollutant Assessment

Source: doi: 10.1289/EHP152.Reproduced with permission from Environmental Health Perspectives.Background:Disruption of thyroid homeostasis has been indicated in human studies targeting effects of persistent organic pollutants (POPs). Influence on the maternal thyroid system by POPs is of special interest during pregnancy because such effects could impair infant thyroid homeostasis. Objectives:We investigated the association between POPs and thyroid-stimulating hormone (TSH) and thyroid hormones (THs) in mother and child pairs from the Northern Norway Motherand- Child Contaminant Cohort Study (MISA). Methods:Nineteen POPs and 10 thyroid parameters were analyzed in serum from 391 pregnant women in their second trimester. In addition, TSH concentrations in heel-prick samples from the infants were analyzed by the Norwegian Newborn Screening program. Association studies with a multipollutant approach were performed using multivariate analyses; partial least squares (PLS) regression, hierarchical clustering, and principal component analysis (PCA). Results:Several POPs were significantly associated with TSH and THs: a) PFOS was positively associated with TSH; b) PCBs, HCB, and nonachlors were inversely associated with T3, T4, and FT4; and, c) PFDA and PFUnDA were inversely associated with T3 and FT3. After mutual adjustments for the other contaminants, only PFDA and PFUnDA remained significantly associated with T3 and FT3, respectively. Infants born to mothers within the highest TSH quartile had 10% higher mean concentrations of TSH compared with children born to mothers in the lowest TSH quartile. Conclusion:The present results suggest that background exposures to POPs can alter maternal thyroid homeostasis. This research contributes to the understanding of multipollutant exposures using multivariate statistical approaches and highlights the complexity of investigating environmental concentrations and mixtures in regard to maternal and infant thyroid function