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The effect of water supply during grain growth on grain nitrogen concentration (GNC) and grain nitrogen yield (GNY) of winter wheat (Triticum aestivum L.) was studied in the field experiment on fertile loamy-clay soil in years 2004-2007. The water regime was differentiated using mobile rain shelter (water shortage, treatment S) and drip irrigation (ample water supply, treatment W); rain-fed crop served as the control treatment (R). Wheat was grown without addition of nitrogen and with 200 kg N/ha (N0 and N1, resp.). The effect of water supply on GNC was highly significant (P < 0.001) in fertilized wheat and not significant in N0. Drought significantly increased GNC in comparison with irrigated and rain-fed crop in N1. Average grain nitrogen concentrations in respective treatments S, R and W were 1.52, 1.54 and 1.56% in N0 and 2.50, 2.24 and 2.07% in N1. Water availability also significantly affected grain nitrogen yield (P < 0.01). The GNY of fertilized wheat under water shortage was significantly lower (139 kg/ha) than GNY in treatments R (174 kg/ha) and W (182 kg/ha) while under N0 the differences were not significant. Unlike GNC, the GNY was positively associated with mineral N supply (Nmin) in 0-90 cm depth in early spring (r = 0.98-0.99 and 0.83-0.97 for N0 and N1, resp.). Several weather and related characteristics showed relations to GNY and GNC, often opposite under N0 and N1. Nmin together with nitrogen fertilization rate, indicators of water regime and temperature during grain growth period explained 78-97% of observed variability of GNC and GNY in the experiment.

The apparent uptake of mineral nitrogen (Nmin) from top- and subsoil layers during the growth of winter wheat (Triticum aestivum L.) was studied in Prague-Ruzyne on clay loam Chernozem soil in years 1996-2003. Two (N0, N1) and three treatments, unfertilized (N0), fertilized with 100 kg (N1) and 200 kg (N2) nitrogen per hectare were observed in years 1996-2000 and 2001-2003, respectively. The apparent uptake of nitrogen from soil layers was calculated from the changes of Nmin content between sampling terms. Most of available mineral N in the soil down to 90 cm was almost fully depleted between tillering and anthesis in treatment N0. The uptake from subsoil layers was delayed and it continued during the period of grain filling in fertilized treatments. Nitrogen fertilization reduced utilization of N from subsoil. The apparent uptake of N from the zone 50-120 cm ranged from 21 to 62 kg N/ha in N0 and from 15 to 60 kg N/ha in N1 in years 1996-2000. In years 2001-2003 the corresponding values (50-130 cm) were 24-104 kg, 43-130 kg and 29-94 kg N/ha in treatments N0, N1 and N2, respectively. The uptake from 120 (130)-150 cm was around zero in a half of experimental years, and it reached at maximum 12 kg/ha in N0 in 1997. There was a strong linear relation between the amount of Nmin in spring and the depletion of nitrogen from the zone 50-120 (130) cm, R2 = 0.94, 0.91 and 0.99 in N0, N1 and N2, respectively.

The effect of nitrogen fertilization on root length (RL) distribution of winter wheat (Triticum aestivum L.) was investigated. The study was conducted in Prague-Ruzyne on clay loam Chernozemic soil in the years 1996-2003. Two (N0, N1) and three (N0, N1, N2) treatments, unfertilized (N0), fertilized with 100 kg (N1) and 200 kg N/ha (N2) were studied in 1996-2000 and 2001-2003, respectively. Nitrogen rate 100 kg/ha had no effect on RL in soil layers (P > 0.1) in years 1996-2000 and 2002-2003 and there was not significant interaction between N treatment and soil layer except for year 1998 (P < 0.01). Nitrogen fertilization affected RL distribution significantly (P = 0.013) only in 2001 due to reduction of root growth in subsoil layers in treatment N2 (200 kg N/ha) in comparison with N0 and N1. The effect of N fertilization on total RL in rooted soil volume was insignificant. There was a significant effect of year on total RL (P < 0.01) but not of interaction of year and N treatment. Roots reached, with the exception of two years, the depth between 100 and 130 cm. Nitrogen fertilization (N1) had no effect (P = 0.59) on rooting depth (RD) in years 1996-2000 but there was a significant effect of interaction between year and N fertilization on RD (P < 0.01). In the second experimental series (2001-2003) N fertilization rate 200 kg N/ha significantly reduced maximum RD (P < 0.01) in comparison with N0 and N1. The year had highly significant effect on RD.

Spatial variability of soil mineral nitrogen Nmin (N-NH4+, N-NO3-) in a soil profile down to 60 cm was determined in a 19-ha experimental field in Prague-Ruzyně for four years. Winter wheat was grown in the years 2000 and 2001, oats in 2002 and mustard in 2003. Root length distribution and depth of the crops were determined at four locations representing different soil conditions within the experimental field. The coefficient of variation as the measure of the variability of nitrate N in topsoil and subsoil (0-30 and 30-60 cm, respectively) in the experimental years ranged between 18-39 and 20-37%, respectively. It was mostly the same or slightly greater in subsoil than in topsoil in respective years. The variability of ammonium N in topsoil and subsoil ranged between 4-58 and 11-27%, respectively. It was similar in topsoil and subsoil, except for autumn 2000. There was a positive relation between nitrate content in top and subsoil on all sampling terms. We did not find a relationship between Nmin contents in experimental years. Spatial dependencies were evaluated on the basis of model variogram parameters. The nugget value expressed as a percentage value of the total variogram's sill was used for the class of spatial dependence determination. When a spatial dependence of the observed factor was found it was within a range of medium-strong dependence. Only in two cases a strong spatial dependence was found. A considerable variability was also found out in the variogram's range, which was between 61 and396 m. All these facts pose a problem for further actions, such as appropriate design of a sampling grid, measured data spatial interpolation and application maps design.

Background Influenza causes substantial morbidity and annual vaccination is the most important prevention strategy. Accurately measuring vaccine effectiveness (VE) is difficult. The clinical syndrome most closely associated with influenza virus infection, influenza-like illness (ILI), is not specific. In addition, laboratory confirmation is infrequently done, and available rapid diagnostic tests are imperfect. The objective of this study was to estimate the joint impact of rapid diagnostic test sensitivity and specificity on VE for three types of study designs: a cohort study, a traditional case-control study, and a case-control study that used as controls individuals with ILI who tested negative for influenza virus infection. Methods We developed a mathematical model with five input parameters: true VE, attack rates (ARs) of influenza-ILI and non-influenza-ILI and the sensitivity and specificity of the diagnostic test. Results With imperfect specificity, estimates from all three designs tended to underestimate true VE, but were similar except if fairly extreme inputs were used. Only if test specificity was 95% or more or if influenza attack rates doubled that of background illness did the case-control method slightly overestimate VE. The case-control method usually produced the highest and most accurate estimates, followed by the test-negative design. The bias toward underestimating true VE introduced by low test specificity increased as the AR of influenza- relative to non-influenza-ILI decreases and, to a lesser degree, with lower test sensitivity. Conclusions Demonstration of a high influenza VE using tests with imperfect sensitivity and specificity should provide reassurance that the program has been effective in reducing influenza illnesses, assuming adequate control of confounding factors. [ABSTRACT FROM AUTHOR]

The molecular organization of exocytic vesicles regulates their transport and fusion. Prasai, Taraska, and colleagues use correlative light and electron microscopy, along with 3D tomography and gold labeling, to directly map proteins on single exocytic organelles at the plasma membrane.

BackgroundDespite the success of rotavirus vaccines over the last decade, rotavirus remains a leading cause of severe diarrheal disease among young children. Further progress in reducing the burden of disease is inhibited, in part, by vaccine underperformance in certain settings. Early trials suggested that oral poliovirus vaccine (OPV), when administered concomitantly with rotavirus vaccine, reduces rotavirus seroconversion rates after the first rotavirus dose with modest or nonsignificant interference after completion of the full rotavirus vaccine course. Our study aimed to identify a range of individual-level characteristics, including concomitant receipt of OPV, that affect rotavirus vaccine immunogenicity in high- and low-child-mortality settings, controlling for individual- and country-level factors. Our central hypothesis was that OPV administered concomitantly with rotavirus vaccine reduced rotavirus vaccine immunogenicity.Methods and findingsPooled, individual-level data from GlaxoSmithKline's Phase II and III clinical trials of the monovalent rotavirus vaccine (RV1), Rotarix, were analyzed, including 7,280 vaccinated infants (5-17 weeks of age at first vaccine dose) from 22 trials and 33 countries/territories (5 countries/territories with high, 13 with moderately low, and 15 with very low child mortality). Two standard markers for immune response were examined including antirotavirus immunoglobulin A (IgA) seroconversion (defined as the appearance of serum antirotavirus IgA antibodies in subjects initially seronegative) and serum antirotavirus IgA titer, both collected approximately 4-12 weeks after administration of the last rotavirus vaccine dose. Mixed-effect logistic regression and mixed-effect linear regression of log-transformed data were used to identify individual- and country-level predictors of seroconversion (dichotomous) and antibody titer (continuous), respectively. Infants in high-child-mortality settings had lower odds of seroconverting compared with infants in low-child-mortality settings (odds ratio [OR] = 0.48, 95% confidence interval [CI] 0.43-0.53, p < 0.001). Similarly, among those who seroconverted, infants in high-child-mortality settings had lower IgA titers compared with infants in low-child-mortality settings (mean difference [β] = 0.83, 95% CI 0.77-0.90, p < 0.001). Infants who received OPV concomitantly with both their first and their second doses of rotavirus vaccine had 0.63 times the odds of seroconverting (OR = 0.63, 95% CI 0.47-0.84, p = 0.002) compared with infants who received OPV but not concomitantly with either dose. In contrast, among infants who seroconverted, OPV concomitantly administered with both the first and second rotavirus vaccine doses was found to be positively associated with antirotavirus IgA titer (β = 1.28, 95% CI 1.07-1.53, p = 0.009). Our findings may have some limitations in terms of generalizability to routine use of rotavirus vaccine because the analysis was limited to healthy infants receiving RV1 in clinical trial settings.ConclusionsOur findings suggest that OPV given concomitantly with RV1 was a substantial contributor to reduced antirotavirus IgA seroconversion, and this interference was apparent after the second vaccine dose of RV1, as with the original clinical trials that our reanalysis is based on. However, our findings do suggest that the forthcoming withdrawal of OPV from the infant immunization schedule globally has the potential to improve RV1 performance.

Viral hepatitis affects millions of people worldwide, with host immunity deciding on the outcome of infection. In patients with haematological malignancies or recipients of haematopoietic stem cells the virus may cause life-threatening complications either due to the virus itself or to the need to interrupt or reduce the chemotherapy. The infected haematopoietic stem cell donor can also transmit viral hepatitis. Knowing complete HBV (hepatitis B virus) serostatus is essential for the right choice of treatment, prophylaxis or pre-emptive approach. Recent recommendations favour treatment using molecules with a high barrier to resistance. In HCV infection, administration of new, direct-acting antiviral agents (DAA), is safe in haematological patients. The use of DAAs in first line is recommended, either as a single treatment for indolent lymphomas or in combination with chemotherapy for aggressive lymphomas. Due to the existing risk of chronic hepatitis E in immunocompromised patients, marker screening should be performed if there are signs and symptoms of hepatitis. In the case of HEV infection, reduction in immunosuppression is recommended and if not possible or unsuccessful, treatment with ribavirin may be considered. Hepatitis A does not progress to chronicity but may be more severe in elderly and immunocompromised patients with risk of hepatic failure. The CELL (Czech Leukaemia Study Group - for Life) Working Group for the Treatment of Opportunistic Infections recommends that all patients undergo screening for hepatotropic viruses before haematological treatment and that patients or donors of haematopoietic stem cells with markers of previous or current viral hepatitis should be consulted with specialists (infectious disease specialist/hepatologists). The screening, vaccination and treatment guidelines outlined here were presented and discussed at the CELL workshop in Brno in May 2018. [ABSTRACT FROM AUTHOR]

Measures to decrease contact between persons during an influenza pandemic have been included in pandemic response plans. We used stochastic simulation models to explore the effects of school closings, voluntary confinements of ill persons and their household contacts, and reductions in contacts among long-term care facility (LTCF) residents on pandemic-related illness and deaths. Our findings suggest that school closings would not have a substantial effect on pandemic-related outcomes in the absence of measures to reduce out-of-school contacts. However, if persons with influenzalike symptoms and their household contacts were encouraged to stay home, then rates of illness and death might be reduced by ≈50%. By preventing ill LTCF residents from making contact with other residents, illness and deaths in this vulnerable population might be reduced by ≈60%. Restricting the activities of infected persons early in a pandemic could decrease negative health impact.