A toddler PCV booster dose following 3 infancy priming doses increases circulating serotype-specific IGG levels but does not increase protection against carriage

Publication date: 11 May 2018
Source:Vaccine, Volume 36, Issue 20
Author(s): Ron Dagan, Shalom Ben-Shimol, Birgit Simell, David Greenberg, Nurith Porat, Helena Käyhty, Noga Givon-Lavi
BackgroundWe compared PCV7 serological response and protection against carriage in infants receiving 3 doses (2, 4, 6 months; 3+0 schedule) to those receiving a booster (12 months; 3+1).MethodsA prospective, randomized controlled study, conducted between 2005 and 2008, before PCVs were implemented in Israel. Healthy infants were randomized 1:1:1 to receive 3+1, 3+0 and 0+2 (control group; 12, 18 months doses). Nasopharyngeal/oropharyngeal swabs were obtained at all visits. Serum serotype-specific IgG concentrations and opsonic activities (OPA) were measured at 2, 7, 13 and 19 months. This study was registered with Current Controlled Trials, Ltd. ISRCTN28445844.ResultsOverall, 544 infants were enrolled: 3+1 (n = 178), 3+0 (n = 178) and 0+2 (n = 188).Post-priming (7 months), antibody concentrations were similar in both groups, except for serotype 18C (higher in 3+0). Post-booster (13, 19 months), ELISA and OPA levels were significantly higher in 3+1 than in 3+0 group.Nasopharyngeal/oropharyngeal cultures were positive for Streptococcus pneumoniae in 2673 (54.3%) visits. Acquisition rates (vaccine and non-vaccine serotypes) were similar for 3+1 and 3+0 groups at 7–30 months and for 0+2 group at 19–30 months.ConclusionsPCV7 booster after 3 priming doses increased substantially IgG concentrations but did not further reduced vaccine-serotype nasopharyngeal acquisition, suggesting that protection from pneumococcal carriage does not depend primarily on serum IgG.



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Local thermal reaction after influenza vaccination: Quantification by infrared imaging and biometric considerations

Publication date: 11 May 2018
Source:Vaccine, Volume 36, Issue 20
Author(s): Andreas Hoffmann, Claudia Dumke, Kay-Martin Ove Hanschmann, Sabine Wicker
BackgroundExtensive clinical investigations are mandatory to evaluate the safety and reactogenicity of vaccines. The recording of common adverse events like injection site soreness or general discomfort derives from individual subjective perceptions. Thermal imaging at the injection site possibly provides a non-subjective and a non-invasive approach to supplement this evaluation.ResultsA protocol for quantified injection-site infrared imaging included 86 participants during a flu vaccine campaign, 40% of whom had a thermal reaction of 1 °C; 25–30% had no thermal response. There was little subjective pain reporting and no clinical correlations were observed except with post-vaccination erythema.Higher responses were linked with advanced age and multiple previous vaccinations.ConclusionEvan if influenza vaccine was only moderately reactogenic, a thermal response was detectable in about 70% of vaccinees, though no relationship to reactogenicity was seen.Infrared imaging might however be a prospective tool for individual studies of vaccine-induced vascular responses.



https://ift.tt/2K3yDBz

Direct-to-adolescent text messaging for vaccine reminders: What will parents permit?

Publication date: 11 May 2018
Source:Vaccine, Volume 36, Issue 20
Author(s): James R. Roberts, Kristen Morella, Erin H. Dawley, Christi A. Madden, Robert M. Jacobson, Charlene Pope, Boyd Davis, David Thompson, Elizabeth S. O'Brien, Paul M. Darden
BackgroundDirect-to-adolescent text messaging may be a consideration for vaccine reminders, including human papilloma virus (HPV), but no studies have explored the minimum age at which parents would allow adolescents to receive a text message.MethodsWe distributed a survey to parents of 10–17 year olds during any office visit in two practice based research networks in South Carolina and Oklahoma. We asked about parental preference for receiving vaccine reminders for their adolescent, whether they would allow the healthcare provider to directly message their adolescent, and if so, what would be the acceptable minimum age.ResultsIn 546 surveys from 11 practices, parents of females were more supportive of direct-to-teen text message reminders than were parents of males, (75% v. 60%, p < .001). The median age at which parents would allow direct text messages from physicians' offices was 14 in females compared to 15 in males, p = .049. We found a correlation between the child's age and the youngest age at which parents would allow a direct text message. Of the parents who permitted a text message directly to their adolescent, most reported an allowable age higher than their adolescent's current age until the age of 15.ConclusionOur study suggests that direct-to-adolescent text messaging would be allowed by parents for older adolescents. This supports an intervention aimed at older adolescents, such as for receipt of MCV4 dose #2, delayed HPV vaccine series completion and annual influenza vaccination.



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Inclusion of the murine IgGκ signal peptide increases the cellular immunogenicity of a simian adenoviral vectored Plasmodium vivax multistage vaccine

Publication date: 11 May 2018
Source:Vaccine, Volume 36, Issue 20
Author(s): Jairo A. Fonseca, Jessica N. McCaffery, Juan Caceres, Elena Kashentseva, Balwan Singh, Igor P. Dmitriev, David T. Curiel, Alberto Moreno
IntroductionCellular and humoral immune responses are both involved in protection against Plasmodium infections. The only malaria vaccine available, RTS,S, primarily induces short-lived antibodies and targets only a pre-erythrocytic stage antigen. Inclusion of erythrocytic stage targets and enhancing cellular immunogenicity are likely necessary for developing an effective second-generation malaria vaccine. Adenovirus vectors have been used to improve the immunogenicity of protein-based vaccines. However, the clinical assessment of adenoviral-vectored malaria vaccines candidates has shown the induction of robust Plasmodium-specific CD8+ but not CD4+ T cells. Signal peptides (SP) have been used to enhance the immunogenicity of DNA vaccines, but have not been tested in viral vector vaccine platforms.ObjectivesThe objective of this study was to determine if the addition of the SP derived from the murine IgGκ light chain within a recombinant adenovirus vector encoding a multistage P. vivax vaccine candidate could improve the CD4+ T cell response.MethodsIn this proof-of-concept study, we immunized CB6F1/J mice with either the recombinant simian adenovirus 36 vector containing the SP (SP-SAd36) upstream from a transgene encoding a chimeric P. vivax multistage protein or the same SAd36 vector without the SP. Mice were subsequently boosted twice with the corresponding recombinant proteins emulsified in Montanide ISA 51 VG. Immunogenicity was assessed by measurement of antibody quantity and quality, and cytokine production by T cells after the final immunization.ResultsThe SP-SAd36 immunization regimen induced significantly higher antibody avidity against the chimeric P. vivax proteins tested and higher frequencies of IFN-γ and IL-2 CD4+ and CD8+ secreting T cells, when compared to the unmodified SAd36 vector.ConclusionsThe addition of the murine IgGκ signal peptide significantly enhances the immunogenicity of a SAd36 vectored P. vivax multi-stage vaccine candidate in mice. The potential of this approach to improve upon existing viral vector vaccine platforms warrants further investigation.



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School-age children and adolescents suspected of having been to be infected with pertussis in Japan

Publication date: 11 May 2018
Source:Vaccine, Volume 36, Issue 20
Author(s): Yosuke Yasui, Toshikatsu Mitsui, Tomoyasu Nishimura, Keiko Uchida, Mikako Inokuchi, Masaaki Mori, Mitsuaki Tokumura, Tetsuo Nakayama
Many countries including Japan have adapted acellular pertussis vaccines combined with diphtheria and tetanus toxoids (DTaP). DTaP vaccine coverage is approximately >90%, but pertussis re-emergence has been observed since 2000 in Japan. In the present study, anti-pertussis antibodies were investigated among school-age children and adolescents from 2013 to 2015. The positive rate of anti-pertussis toxin (PT) antibodies was higher among children aged 12–13 years (60.0%. 95%CI; 56.0–63.9%) in 2014 and 18–19 years (73.0%. 95%CI; 61.4–82.6%) in 2013, compared with 6–7 years (47.1%. 95%CI; 40.7–53.6%). The mean PT antibody titer was higher among children aged 12–13 years (23.8 EU/ml. 95%CI; 21.9–25.8) in 2014 and 18–19 years (29.3 EU/ml. 95%CI; 23.0–35.6) in 2013, compared with 6–7 years (18.3 EU/ml. 95%CI; 15.5–21.2). Distributions of pertussis antibodies and mean titers at their same grade of school-age were similar from 2013 to 2015. Although school-age children were immunized with 4 doses of DTaP, the data suggested the decay of vaccine-acquired immunity and possibility of asymptomatic infection in school age, indicating the additional DTaP vaccination before the entry of elementary school, preventing household contact.



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Analysis of adenovirus-induced immunity to infection with Listeria monocytogenes: Fading protection coincides with declining CD8 T cell numbers and phenotypic changes

Publication date: 11 May 2018
Source:Vaccine, Volume 36, Issue 20
Author(s): Marie Louise Jahn, Maria Abildgaard Steffensen, Jan Pravsgaard Christensen, Allan Randrup Thomsen
Defining correlates of T cell mediated protection is important in order to accelerate the development of efficient T cell based vaccines conferring long-term immunity.Extensive studies have provided important insight regarding the characteristics and functional properties of the effector and memory CD8 T cells induced by viral vector based vaccines. However, long-term protection has been difficult to achieve with T cell inducing vaccines, and the determinants underlying this loss in protection over time are still not fully defined.In this study we analyzed different parameters of the CD8 T cell response as a function of time after vaccination with a human serotype 5 adenovector expressing the glycoprotein (GP) of LCMV tethered to the MHC class II-associated invariant chain. Using this vector we have previously found that CD8 T cells mediate protection from challenge with GP-expressing Listeria monocytogenes at 60 days post vaccination, but only little protection after further 60 days, and we now confirm this observation. A comparison of vaccine-primed CD8 T cells early and late after vaccination revealed a minor decline in the overall numbers of antigen specific memory CD8 T cells during this interval. More importantly, we also observed phenotypic changes over time with a distinct decline in the frequency and number of KLRG1⁺ CD8 T cells, and, notably, adoptive transfer studies confirmed that memory CD8 T cells expressing KLRG1 are central to protection from systemic L. monocytogenes infection. Together these findings imply that multiple factors including changes in memory T cell numbers and phenotypic composition over time influence the longevity of CD8 T-cell mediated protection.



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Intramuscular vaccination of guinea pigs with the live-attenuated human herpes simplex vaccine VC2 stimulates a transcriptional profile of vaginal Th17 and regulatory Tr1 responses

Publication date: 11 May 2018
Source:Vaccine, Volume 36, Issue 20
Author(s): Brent A. Stanfield, Paul J.F. Rider, John Caskey, Fabio Del Piero, Konstantin G. Kousoulas
Herpes simplex virus is a common causative agent of oral and genital diseases. Novel vaccines and therapeutics are needed to combat herpes infections especially after the failure of subunit vaccines in human clinical trials. We have shown that the live-attenuated HSV-1 VC2 vaccine strain is unable to establish latency in vaccinated animals and produces a robust immune response capable of completely protecting mice against lethal vaginal HSV-1 or HSV-2 infections. The guinea pig represents the best small animal model of genital HSV-2 disease. Reported here, twenty-one female Hartley guinea pigs received intramuscular injection with either the VC2 vaccine, or equal volume of conditioned tissue culture media. Animals received 2 booster vaccinations at 21 day intervals following the initial vaccination. After vaccination, animals were challenged with the highly virulent HSV-2 (G) strain. Histologically, VC2 vaccinated animals had little to no apparent inflammation/disease following challenge. Unvaccinated animals developed moderate to severe erosive and ulcerative vaginitis. Quantitative reverse-transcriptase PCR analysis in VC2 vaccinated and challenged animals identified transcriptional signatures of Th17 and regulatory Tr1 cells associated with the inflammatory response primed by VC2 vaccination. Treatment of cultured human vaginal epithelial cells (VK2 cells) with a combination of IL-17A and IL-22 resulted in the significant induction of beta-defensin 3 expression. Further, treatment of VK2 cells with IL-17A, IL-22, IL-36 or beta-defensin 3 resulted in diminished HSV-2 replication. Overall, these results suggest that intramuscular vaccination with the live-attenuated vaccine VC2 primes a mucosal immune response predisposing the adaptive expression of transcripts associated with a Th17 response to challenge and these responses contribute to antiviral immunity.



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Ag85A-specific CD4+ T cell lines derived after boosting BCG-vaccinated cattle with Ad5-85A possess both mycobacterial growth inhibition and anti-inflammatory properties

Publication date: 11 May 2018
Source:Vaccine, Volume 36, Issue 20
Author(s): Hannah J. Metcalfe, Lucia Biffar, Sabine Steinbach, Efrain Guzman, Tim Connelley, Ivan Morrison, H. Martin Vordermeier, Bernardo Villarreal-Ramos
There is a need to improve the efficacy of the BCG vaccine against human and bovine tuberculosis. Previous data showed that boosting bacilli Calmette-Guerin (BCG)-vaccinated cattle with a recombinant attenuated human type 5 adenovirally vectored subunit vaccine (Ad5-85A) increased BCG protection and was associated with increased frequency of Ag85A-specific CD4⁺ T cells post-boosting. Here, the capacity of Ag85A-specific CD4⁺ T cell lines – derived before and after viral boosting – to interact with BCG-infected macrophages was evaluated. No difference before and after boosting was found in the capacity of these Ag85A-specific CD4⁺ T cell lines to restrict mycobacterial growth, but the secretion of IL-10 in vitro post-boost increased significantly. Furthermore, cell lines derived post-boost had no statistically significant difference in the secretion of pro-inflammatory cytokines (IL-1β, IL-12, IFNγ or TNFα) compared to pre-boost lines. In conclusion, the protection associated with the increased number of Ag85A-specific CD4⁺ T cells restricting mycobacterial growth may be associated with anti-inflammatory properties to limit immune-pathology.



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A follow-up comparative safety analysis of pandemic H1N1 vaccination during pregnancy and risk of infant birth defects among U.S. military mothers

Publication date: 11 May 2018
Source:Vaccine, Volume 36, Issue 20
Author(s): Ava Marie S. Conlin, Anna T. Bukowinski, Jordan A. Levine, Zeina G. Khodr, Navjot Kaur, Susan C. Farrish, Carter J. Sevick
ObjectiveTo update a previous assessment of birth defects among infants born to active duty U.S. military mothers who received the 2009–2010 pandemic H1N1 vaccine, in comparison to the 2008–2009 seasonal influenza vaccine, during pregnancy. Here, we updated the previous comparative analyses with a more refined definition for birth defects using an additional year of follow-up data from both inpatient and outpatient medical encounters.MethodsThe study population included 15,510 live born infants born to active duty mothers vaccinated during pregnancy with either the 2009–2010 pandemic H1N1 vaccine (n = 9033) or the 2008–2009 seasonal influenza vaccine (n = 6477). Birth defect cases were defined as those infants who received a birth defect diagnosis on one inpatient record or two outpatient records on different days within the first year of life. Multivariable logistic regression models were conducted to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) for the association between birth defects and maternal vaccination during pregnancy with pandemic H1N1 vaccine versus seasonal influenza vaccine.ResultsInfants born to mothers vaccinated during pregnancy with the pandemic H1N1 vaccine, versus the seasonal influenza vaccine, were not at increased odds of birth defects in univariable (OR: 1.13, 95% CI: 0.95–1.34) or multivariable (OR: 1.14, 95% CI: 0.96–1.35) models. Findings were not significant when further limited to first trimester exposure. Multivariable models were adjusted for infant sex and plurality; maternal age, race/ethnicity, marital status, service branch, military rank, and occupation; timing of vaccination; and receipt of vaccination(s) not routinely recommended during pregnancy.ConclusionComparable to our previous analyses assessing birth defects diagnosed at birth, no significant association was found between the pandemic H1N1 vaccination during pregnancy and birth defects, versus the seasonal influenza vaccine. These findings are reassuring and provide additional support for H1N1-containing seasonal influenza vaccination during pregnancy.



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Post-immunization leucocytosis and its implications for the management of febrile infants

Publication date: 11 May 2018
Source:Vaccine, Volume 36, Issue 20
Author(s): Sarah Prentice, Zephyrian Kamushaaga, Stephen B. Nash, Alison M. Elliott, Hazel M. Dockrell, Stephen Cose
AimsClinical guidelines for management of infants with fever but no evident focus of infection recommend that those aged 1–3 months with a white cell count >15 × 10⁹/l have a full septic screen and be admitted for parenteral antibiotics. However, there is limited information about leucocyte changes following routine immunization, a common cause of fever. We investigated white cell counts shortly after routine immunization in Ugandan infants under 3 months of age.MethodsWhite cell counts were measured in 212 healthy infants following routine immunizations (DTwP-HepB-Hib, oral polio and pneumococcal conjugate 7 vaccines) received prior to 3 months of age.ResultsMean leucocyte counts increased from 9.03 × 10⁹/l (95% confidence interval 8.59–9.47 × 10⁹/l) pre-immunizations to 16.46 × 10⁹/l (15.4–17.52 × 10⁹/l) at one-day post-immunizations at 6 weeks of age, and 15.21 × 10⁹/l (14.07–16.36 × 10⁹/l) at one-day post-immunizations at 10 weeks of age. The leucocytosis was primarily a neutrophilia, with neutrophil percentages one-day post-immunization of 49% at 6 weeks of age and 46% at 10 weeks of age. White cell parameters returned to baseline by two-days post-immunization. No participant received antibiotics when presenting with isolated fever post-immunization and all remained well at follow-up.ConclusionsIn our study almost half the children <3 months old presenting with fever but no evident focus of infection at one-day post-immunization met commonly used criteria for full septic screen and admission for parenteral antibiotics, despite having no serious bacterial infection. These findings add to the growing body of literature that questions the utility of white blood cell measurement in identification of young infants at risk of serious bacterial infections, particularly in the context of recent immunizations, and suggest that further exploration of the effect of different immunization regimes on white cell counts is needed.This observational work was nested within a clinical trial, registration number ISRCTN59683017.



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A novel method for strict intranasal delivery of non-replicating RSV vaccines in cotton rats and non-human primates

Publication date: 11 May 2018
Source:Vaccine, Volume 36, Issue 20
Author(s): Michael P. Citron, Manishkumar Patel, Mona Purcell, Shu-An Lin, Daniel J. Rubins, Paul McQuade, Cheryl Callahan, Alexa Gleason, Ioan Petrescu, Walter Knapp, Chinedu Orekie, Sai Chamarthy, Zhiyun Wen, Sinoeun Touch, Matthew Pine, Jane Fontenot, Cameron Douglas, Xiaoping Liang, Amy S. Espeseth
Respiratory syncytial virus (RSV) is the most common viral cause of bronchiolitis and pneumonia in children twelve months of age or younger and a significant cause of lower respiratory disease in older adults. As various clinical and preclinical candidates advance, cotton rats (Sigmodon hispidus) and non-human primates (NHP) continue to play a valuable role in RSV vaccine development, since both animals are semi-permissive to human RSV (HRSV). However, appropriate utilization of the models is critical to avoid mis-interpretation of the preclinical findings. Using a multimodality imaging approach; a fluorescence based optical imaging technique for the cotton rat and a nuclear medicine based positron emission tomography (PET) imaging technique for monkeys, we demonstrate that many common practices for intranasal immunization in both species result in inoculum delivery to the lower respiratory tract, which can result in poor translation of outcomes from the preclinical to the clinical setting. Using these technologies we define a method to limit the distribution of intranasally administered vaccines solely to the upper airway of each species, which includes volume restrictions in combination with injectable anesthesia. We show using our newly defined methods for strict intranasal immunization that these methods impact the immune responses and efficacy observed when compared to vaccination methods resulting in distribution to both the upper and lower respiratory tracts. These data emphasize the importance of well-characterized immunization methods in the preclinical assessment of intranasally delivered vaccine candidates.



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Nasal vaccination with r4M2e.HSP70c antigen encapsulated into N-trimethyl chitosan (TMC) nanoparticulate systems: Preparation and immunogenicity in a mouse model

Publication date: 11 May 2018
Source:Vaccine, Volume 36, Issue 20
Author(s): Mehran Dabaghian, Ali Mohammad Latifi, Majid Tebianian, Hamid NajmiNejad, Seyyed Mahmoud Ebrahimi
In this study, the potential of N-trimethyl chitosan (TMC) nanoparticles as a carrier system for the nasal delivery of the r4M2e.HSP70c, as an M2e-based universal recombinant influenza virus vaccine candidate, was investigated in mice. The anti-M2e specific cellular and humoral immune responses were assessed and the protective efficacy against a 90% lethal dose (LD90) of influenza A/PR/8/34 (H1N1) in a mice model was evaluated.Our results showed that the intranasal immunization of mice with r4M2e.HSP70c+TMC rather than the control groups, r4M2e+TMC, r4M2e and PBS (Phosphate buffer saline), significantly elevated both longevity and serum level of the total M2e-specific IgG antibody with a significant shift in the IgG2a/IgG1 ratio toward IgG2a, induced a Th1 skewed humoral and cellular immune responses, increased IFN-γ, IgG, and IgA in the bronchoalveolar lavage fluid (BALF), and promoted the proliferation of peripheral blood lymphocytes with lower morbidity and mortality rate against viral challenge.In conclusion, based on evidence to our finding, nasal vaccination with r4M2e.HSP70c antigen encapsulated into N-Trimethyl Chitosan (TMC) nanoparticulate system showed to induce a long lasting M2e-specific humoral and cellular immune responses and also provided full protection against a 90% lethal dose (LD90) of the influenza virus A/PR/8/34 (H1N1). It seems, protective immunity following intranasal administration of r4M2e could be resulted by the cooperation of both adjuvants, TMC and HSP70c.



https://ift.tt/2K1GFdX

Vaccine delivery to newly arrived refugees and estimated costs in selected U.S. clinics, 2015

Publication date: 11 May 2018
Source:Vaccine, Volume 36, Issue 20
Author(s): Clelia Pezzi, Audrey McCulloch, Heesoo Joo, Jennifer Cochran, Laura Smock, Ellen Frerich, Blain Mamo, Kailey Urban, Stephen Hughes, Colleen Payton, Kevin Scott, Brian Maskery, Deborah Lee
BackgroundNewly arrived refugees are offered vaccinations during domestic medical examinations. Vaccination practices and costs for refugees have not been described with recent implementation of the overseas Vaccination Program for U.S.-bound Refugees (VPR). We describe refugee vaccination during the domestic medical examination and the estimated vaccination costs from the US government perspective in selected U.S. clinics.MethodsSite-specific vaccination processes and costs were collected from 16 clinics by refugee health partners in three states and one private academic institution. Vaccination costs were estimated from the U.S. Vaccines for Children Program and Medicaid reimbursement rates during fiscal year 2015.ResultsAll clinics reviewed overseas vaccination records before vaccinating, but all records were not transferred into state immunization systems. Average vaccination costs per refugee varied from $120 to $211 by site. The total average cost of domestic vaccination was 15% less among refugees arriving from VPR- vs. nonVPR-participating countries during a single domestic visit.ConclusionOur findings indicate that immunization practices and costs vary between clinics, and that clinics adapted their vaccination practices to accommodate VPR doses, yielding potential cost savings.



https://ift.tt/2JihrXL

Mayor campo de actuación de la cardiología nuclear

Publication date: May–June 2018
Source:Revista Española de Medicina Nuclear e Imagen Molecular, Volume 37, Issue 3
Author(s): I. Casáns Tormo




https://ift.tt/2Jg0Cwm

The mixed potential type gas sensor based on stabilized zirconia and molybdate MMoO4 (M: Ni, Co and Zn) sensing electrode aiming at detecting triethylamine

Publication date: 15 August 2018
Source:Sensors and Actuators B: Chemical, Volume 267
Author(s): Fangmeng Liu, Junming He, Zijie Yang, Rui You, Jing Wang, Lianjing Zhao, Qingji Wang, Xishuang Liang, Peng Sun, Xu Yan, Geyu Lu
The mixed potential type gas sensors utilizing yttria stabilized zirconia (YSZ) solid electrolyte and molybdates MMoO4 (M: Ni, Co and Zn) sensing electrodes (SEs) were fabricated aiming at detecting triethylamine (TEA) at 600 °C. Results indicated that the device attached with NiMoO4-SE exhibited the highest response value of −71 mV to 50 ppm TEA and low detection limit of 100 ppb at 600 °C. Moreover, the response time of the developed sensor to 50 ppm TEA was 3 s, which signified the fast response rate. The response value of fabricated sensor displayed the piecewise linear relationship to logarithm of TEA concentrations and the sensitivities were −4 mV/decade (0.1–1 ppm) and −37 mV/decade (1–100 ppm), respectively. More importantly, the present sensor also exhibited good repeatability, selectivity, slight effect of humidity and stability of 10 days, indicating a great candidate for use in detection of TEA. Furthermore, the device based on mixed potential mechanism was proposed and further verified using polarization curve.



https://ift.tt/2Haiicm

Zinc fertilizers influence greenhouse gas emissions and nitrifying and denitrifying communities in a non-irrigated arable cropland

Publication date: 1 September 2018
Source:Geoderma, Volume 325
Author(s): Mónica Montoya, Antonio Castellano-Hinojosa, Antonio Vallejo, José Manuel Álvarez, Eulogio J. Bedmar, Jaime Recio, Guillermo Guardia
Fertilization with micronutrients (e.g., zinc, Zn) is essential in order to overcome the global nutritional problems associated with human micronutrient deficiencies. However, little is known about the effect of micronutrient fertilizers and their interaction with nitrogen (N) on greenhouse gas (GHG) emissions and soil microbial processes involved in nitrous oxide (N2O) fluxes. In this context, a one-year field experiment was carried out using a winter wheat (Triticum aestivum L.) crop in Central Spain. Winter wheat was treated with different Zn sources (Zn-sulphate, Zn-lignosulphonate, Zn with a mixture of synthetic chelating compounds DTPA-HEDTA-EDTA and Zn-humic/fulvic acids) and N rates (0, 120 and 180 kg N ha⁻¹). Zn sources were applied at 10 kg Zn ha⁻¹ for Zn-sulphate and 0.36 kg Zn ha⁻¹ for the rest of treatments. Nitrous oxide, methane (CH4) and respiration fluxes were measured (two-three times per week during the first month after each fertilization and thereafter with decreasing frequency), as were the total abundances of soil Bacteria and Archaea, ammonia-oxidizing Bacteria and Archaea, and denitrifying bacteria. The DTPA-HEDTA-EDTA reduced cumulative N2O losses by 21.4% and respiration fluxes by 24.4% from those of the no Zn application. The chelating of metal co-factors (mainly copper, Cu) of the enzymes involved in the nitrification and denitrification steps was the probable mechanism for the reduction of N2O emissions as bacterial amoA, nirK, nirS and norB gene abundances, as well as the extractable Cu content, decreased in this treatment. Unexpectedly, the DTPA-HEDTA-EDTA increased the copy number of nosZ by 31.2% over that of the no Zn application. The Zn applied together with the humic/fulvic acids mixture caused significant increases of total bacterial abundance and nitrifier and denitrifier communities, particularly the norB gene, thereby leading to the highest N2O emissions. The optimum N rate was 120 kg N ha⁻¹ since it resulted in the lowest yield-scaled N2O losses and N surplus. The application of synthetic Zn chelates can be recommended as a win-win mitigation and adaptation strategy aimed at reducing yield-scaled GHG emissions and at the enhancement of Zn biofortification.



https://ift.tt/2JbBZ43

Anodic stripping voltammetric determination of zinc at a 3-D printed carbon nanofiber–graphite–polystyrene electrode using a carbon pseudo-reference electrode

Publication date: 15 August 2018
Source:Sensors and Actuators B: Chemical, Volume 267
Author(s): Kevin C. Honeychurch, Zuhayr Rymansaib, Pejman Iravani
The application of a novel fully 3-D printed carbon nanofiber–graphite–polystyrene electrode has been investigated for the trace determination of Zn²⁺ by differential pulse anodic stripping voltammetry. The possibility of utilising a carbon pseudo-reference electrode was found to be successful. The effect of accumulation potential and time were investigated and optimised. Using an accumulation potential of −2.9 V (vs. C) and an accumulation time of 75 s a single sharp anodic stripping peak was recorded exhibiting a linear response from 12.7 μg/L to 450 μg/L. The theoretical detection limit (3σ) was calculated as 8.6 μg/L. Using the optimised conditions a mean recovery of 97.8%, (%CV = 2.0%, n = 5) for a tap water sample fortified at 0.990 μg/mL was obtained indicating the method holds promise for the determination of Zn²⁺ in such samples.



https://ift.tt/2qPMh3a

Cross-regulation between Notch signaling pathway and miRNA machinery in cancer

Publication date: Available online 21 April 2018
Source:DNA Repair
Author(s): Maryam Majidinia, Saber Ghazizadeh Darband, Mojtaba Kaviani, Seyed Mohammad Nabavi, Rana Jahanban-Esfahlan, Bahman Yousefi
Despite their simple structure, the Notch family of receptors regulates a wide-spectrum of key cellular processes including development, tissue patterning, cell-fate determination, proliferation, differentiation and, cell death. On the other hand, accumulating date pinpointed the role of non-coding microRNAs, namely miRNAs in cancer initiation/progression via regulating the expression of multiple oncogenes and tumor suppressor genes, as such the Notch signaling. It is now documented that these two partners are in one or in the opposite directions and rule together the cancer fate. Here, we review the current knowledge relevant to this tricky interplay between different miRNAs and components of Notch signaling pathway. Further, we discuss the implication of this crosstalk in cancer progression/regression in the context of cancer stem cells, tumor angiogenesis, metastasis and emergence of multi-drug resistance. Understanding the molecular cues and mechanisms that occur at the interface of miRNA and Notch signaling would open new avenues for development of novel and effective strategies for cancer therapy.



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International Organization of Psychophysiology

Publication date: May 2018
Source:International Journal of Psychophysiology, Volume 127





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Editorial Board

Publication date: May 2018
Source:International Journal of Psychophysiology, Volume 127





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