17 research outputs found
Microbial degradation of petroleum hydrocarbons - in vitro study
Pollution of the environment by petroleum products is a global problem, since its extensive exploitation in broad areas.Microorganisms can degrade or transform toxic, petroleum derivates into harmless products with high efficiency.This study aimed to investigate the biodegradation process of petroleum hydrocarbons in contaminated sediment usingindigenous and a combination of indigenous and allochthonous microorganisms.The allochthonous microorganisms that were added belonged to the genera Acinetobacter and Citrobacter. The experiment lasted two weeks, and the degradation process took place in a closed vessel on a Micro-Oxymax respirometer.Total petroleum hydrocarbons (TPH) were extracted and determined using a gas chromatograph with a flame ionization detector. The number of microorganisms at the beginning and end of the experiment was also determined.The results on the respirometer and gas chromatography indicated that the microorganisms were metabolically active.Indigenous microorganisms reduce the amount of TPH by 32.0% and the combination of indigenous-allochthonousmicroorganisms by 33.6%. The results showed that there is no significant difference between the application of autochthonous and the combination of indigenous-allochthonous microorganisms for the reduction of TPH in contaminatedsediment, suggesting a high potential of autochthonous microorganisms for bioremediation processes
Microbial degradation of petroleum hydrocarbons - in vitro study
Pollution of the environment by petroleum products is a global problem, since its extensive exploitation in broad areas.
Microorganisms can degrade or transform toxic, petroleum derivates into harmless products with high efficiency.
This study aimed to investigate the biodegradation process of petroleum hydrocarbons in contaminated sediment using
indigenous and a combination of indigenous and allochthonous microorganisms.
The allochthonous microorganisms that were added belonged to the genera Acinetobacter and Citrobacter. The experiment lasted two weeks, and the degradation process took place in a closed vessel on a Micro-Oxymax respirometer.
Total petroleum hydrocarbons (TPH) were extracted and determined using a gas chromatograph with a flame ionization detector. The number of microorganisms at the beginning and end of the experiment was also determined.
The results on the respirometer and gas chromatography indicated that the microorganisms were metabolically active.
Indigenous microorganisms reduce the amount of TPH by 32.0% and the combination of indigenous-allochthonous
microorganisms by 33.6%. The results showed that there is no significant difference between the application of autochthonous and the combination of indigenous-allochthonous microorganisms for the reduction of TPH in contaminated
sediment, suggesting a high potential of autochthonous microorganisms for bioremediation processes
Microbial Recovery of Copper and Zinc from Wasted Electronic Parts
Recycling of electronic waste is crucial not only from the viewpoint of waste treatment but also from aspect of the recovery of valuable metals [1]. The aim of our study was to investigate the potential of using the Acidithiobacillus sp. B2, to solubilize metals (Cu and Zn) from electronic waste. Methodology: Chemical analysis of electronic waste and pyrite The electronic waste (after separating of the plastic parts) and pyrite were pulverized and sieved through a 63 µm stainless steel sieve in preparation for chemical and leaching studies. Electronic waste preparation for the leaching experiment The presence of alkali components in electronic waste is considered inconvenient for the reaction between the electronic waste and the acidic iron(III) sulphate solution. Hence, it is necessary to neutralize the electronic waste before adding the bacterial culture which would generate the oxidant. Before the leaching experiment, electronic waste was dispersed in 0.05 M H2 SO4 solution, shaken for 48 h, filtered from the solution, washed out with deionized water and dried at 110 °C [2]. Preparation of pyrite for the leaching experiments The pyrite concentrate for the leaching experiments was prepared by treating with a 0.5 mol/dm3 sulphuric acid solution (pH ~ 0.5) (solid to liquid phase ratio 1:5 m/V), and mixing with a mechanical stirrer at a room temperature overnight. Then, the solution was decanted, washed with deionized water and dried at 80 °C to a constant mass [2]. Leaching experiments The leaching experiments were carried out with bacterium Acidithiobacillus sp. B2. Experimental conditions were: leaching period of 20 d, 50 ml leaching solution (g/dm3 ): (NH4 )2 SO4 (3), K2 HPO4 (0.5), MgSO4 x 7H2 O(0.5), KCl (0.1), Ca(NO3 )2 (0.01), at a pH of 2.5 in 150 mL Erlenmeyer flasks at a pulp density of 10% (m/V) (5 g leaching substrate in 50 ml solution). The pH of the leaching solution was maintained at a constant value during the leaching process. One half of the substrate was pyrite and the other was an electronic waste. The initial number of microogranisms was 107 per mL, determined by the Most Probable Number method. The control suspension had the same chemical content and pH value as the suspension with Acidithiobacillus sp. B2 but the Acidithiobacillus sp. B2 culture had been inactivated by sterilization. The study was realized on a horizontal shaker. The incubation temperature was 28 °C [2]. Results and conclusions: The results of the effective metal leaching (calculated by subtraction of percentage metal leaching in the control suspension from that in the Acidithiobacillus sp. B2 suspension) are as follows: Zn (38%)>Cu (35%). The obtained results demonstrate that Acidithiobacillus sp. B2 was able to grow in the presence of electronic waste and may be “green” agents in the area of circular economy and sustainable development
Heterologous Two-Dose Vaccination with Simian Adenovirus and Poxvirus Vectors Elicits Long-Lasting Cellular Immunity to Influenza Virus A in Healthy Adults
Background: T-cell responses against highly conserved influenza antigens have been previously associated with
protection. However, these immune responses are poorly maintained following recovery from influenza infection
and are not boosted by inactivated influenza vaccines. We have previously demonstrated the safety and immunogenicity
of two viral vectored vaccines, modified vaccinia virus Ankara (MVA) and the chimpanzee
adenovirus ChAdOx1 expressing conserved influenza virus antigens, nucleoprotein (NP) and matrix protein-1
(M1). We now report on the safety and long-term immunogenicity of multiple combination regimes of these vaccines
in young and older adults.
Methods: We conducted a Phase I open-label, randomized, multi-center study in 49 subjects aged 18–46 years
and 24 subjects aged 50 years or over. Following vaccination, adverse events were recorded and the kinetics of
the T cell response determined at multiple time points for up to 18 months.
Findings: Both vaccines were well tolerated. A two dose heterologous vaccination regimen significantly increased
the magnitude of pre-existing T-cell responses to NP and M1 after both doses in young and older adults. The foldincrease
and peak immune responses after a single MVA-NP + M1 vaccination was significantly higher compared
to ChAdOx1 NP + M1. In a mixed regression model, T-cell responses over 18 months were significantly
higher following the two dose vaccination regimen of MVA/ChAdOx1 NP + M1.
Interpretation: A two dose heterologous vaccination regimen of MVA/ChAdOx1 NP + M1 was safe and immunogenic
in young and older adults, offering a promising vaccination strategy for inducing long-term broadly crossreactive
protection against influenza
Enhancing discovery of genetic variants for posttraumatic stress disorder through integration of quantitative phenotypes and trauma exposure information
Background Posttraumatic stress disorder (PTSD) is heritable and a potential consequence of exposure to traumatic stress. Evidence suggests that a quantitative approach to PTSD phenotype measurement and incorporation of lifetime trauma exposure (LTE) information could enhance the discovery power of PTSD genome-wide association studies (GWASs). Methods A GWAS on PTSD symptoms was performed in 51 cohorts followed by a fixed-effects meta-analysis (N = 182,199 European ancestry participants). A GWAS of LTE burden was performed in the UK Biobank cohort (N = 132,988). Genetic correlations were evaluated with linkage disequilibrium score regression. Multivariate analysis was performed using Multi-Trait Analysis of GWAS. Functional mapping and annotation of leading loci was performed with FUMA. Replication was evaluated using the Million Veteran Program GWAS of PTSD total symptoms. Results GWASs of PTSD symptoms and LTE burden identified 5 and 6 independent genome-wide significant loci, respectively. There was a 72% genetic correlation between PTSD and LTE. PTSD and LTE showed largely similar patterns of genetic correlation with other traits, albeit with some distinctions. Adjusting PTSD for LTE reduced PTSD heritability by 31%. Multivariate analysis of PTSD and LTE increased the effective sample size of the PTSD GWAS by 20% and identified 4 additional loci. Four of these 9 PTSD loci were independently replicated in the Million Veteran Program. Conclusions Through using a quantitative trait measure of PTSD, we identified novel risk loci not previously identified using prior case-control analyses. PTSD and LTE have a high genetic overlap that can be leveraged to increase discovery power through multivariate methods
International meta-analysis of PTSD genome-wide association studies identifies sex- and ancestry-specific genetic risk loci
The risk of posttraumatic stress disorder (PTSD) following trauma is heritable, but robust common variants have yet to be identified. In a multi-ethnic cohort including over 30,000 PTSD cases and 170,000 controls we conduct a genome-wide association study of PTSD. We demonstrate SNP-based heritability estimates of 5–20%, varying by sex. Three genome-wide significant loci are identified, 2 in European and 1 in African-ancestry analyses. Analyses stratified by sex implicate 3 additional loci in men. Along with other novel genes and non-coding RNAs, a Parkinson’s disease gene involved in dopamine regulation, PARK2, is associated with PTSD. Finally, we demonstrate that polygenic risk for PTSD is significantly predictive of re-experiencing symptoms in the Million Veteran Program dataset, although specific loci did not replicate. These results demonstrate the role of genetic variation in the biology of risk for PTSD and highlight the necessity of conducting sex-stratified analyses and expanding GWAS beyond European ancestry populations. © 2019, This is a U.S. government work and not under copyright protection in the U.S.; foreign copyright protection may apply
International meta-analysis of PTSD genome-wide association studies identifies sex- and ancestry-specific genetic risk loci
The risk of posttraumatic stress disorder (PTSD) following trauma is heritable, but robust common variants have yet to be identified. In a multi-ethnic cohort including over 30,000 PTSD cases and 170,000 controls we conduct a genome-wide association study of PTSD. We demonstrate SNP-based heritability estimates of 5–20%, varying by sex. Three genome-wide significant loci are identified, 2 in European and 1 in African-ancestry analyses. Analyses stratified by sex implicate 3 additional loci in men. Along with other novel genes and non-coding RNAs, a Parkinson’s disease gene involved in dopamine regulation, PARK2, is associated with PTSD. Finally, we demonstrate that polygenic risk for PTSD is significantly predictive of re-experiencing symptoms in the Million Veteran Program dataset, although specific loci did not replicate. These results demonstrate the role of genetic variation in the biology of risk for PTSD and highlight the necessity of conducting sex-stratified analyses and expanding GWAS beyond European ancestry populations
Heterologous two-dose vaccination with simian adenovirus and poxvirus vectors elicits long-lasting cellular immunity to influenza virus A in healthy adults
Background T-cell responses against highly conserved influenza antigens have been previously associated with protection. However, these immune responses are poorly maintained following recovery from influenza infection and are not boosted by inactivated influenza vaccines. We have previously demonstrated the safety and immunogenicity of two viral vectored vaccines, modified vaccinia virus Ankara (MVA) and the chimpanzee adenovirus ChAdOx1 expressing conserved influenza virus antigens, nucleoprotein (NP) and matrix protein-1 (M1). We now report on the safety and long-term immunogenicity of multiple combination regimes of these vaccines in young and older adults. Methods We conducted a Phase I open-label, randomized, multi-center study in 49 subjects aged 18–46 years and 24 subjects aged 50 years or over. Following vaccination, adverse events were recorded and the kinetics of the T cell response determined at multiple time points for up to 18 months. Findings Both vaccines were well tolerated. A two dose heterologous vaccination regimen significantly increased the magnitude of pre-existing T-cell responses to NP and M1 after both doses in young and older adults. The fold-increase and peak immune responses after a single MVA-NP + M1 vaccination was significantly higher compared to ChAdOx1 NP + M1. In a mixed regression model, T-cell responses over 18 months were significantly higher following the two dose vaccination regimen of MVA/ChAdOx1 NP + M1. Interpretation A two dose heterologous vaccination regimen of MVA/ChAdOx1 NP + M1 was safe and immunogenic in young and older adults, offering a promising vaccination strategy for inducing long-term broadly cross-reactive protection against influenza A
Corrigendum to “Heterologous Two-dose Vaccination with Simian Adenovirus and Poxvirus Vectors Elicits Long-lasting Cellular Immunity to Influenza Virus A in Healthy Adults” [EBioMedicine 29 (2018) 146–154] (S2352396418300653) (10.1016/j.ebiom.2018.02.011))
The authors wish to point out that L. Coughlan and S. Sridhar were both at the Jenner Institute, University of Oxford, OX3 7DQ, UK, when the work for the paper was completed.</p