42 research outputs found
Enhanced Electrokinetic Transport of Sulfate in Saline Soil
The electrokinetic transport of sulfate was investigated as a means of treating and restoring a sulfate-accumulating saline soil. The electrokinetic treatment decreased the electrical conductivity of the soil, an indicator of soil salinity, to 58.6%, 73.1%, and 83.5% for 7, 14 and 21 days, respectively. More than 96% of the chloride and nitrate were removed within 7 days. However, the removal of sulfate was highly influenced by the anode material. An iron anode removed sulfate effectively, whereas, sulfate was hyper-accumulated in the anodic region when an inert anode was used. The iron anode was oxidized in a sacrificial anodic reaction, which competed with the electrolysis reaction of water at the anode, and finally the reaction prevented the severe acidification of the soil in the anodic region. However, the competing reactions produced hydrogen ions at the anode, and the ions were transported toward the cathode, which, in turn, acidified the soil, especially, in the anodic region. The acidification switched the surface charge of the soil from negative to positive, increasing the interaction between the soil surface and sulfate, and thus inhibiting the transport of sulfate under the electric field. The zeta potential analysis of the soil provided an explanation. The results indicate that preventing severe acidification is an important factor which influences the transport of anions and iron anode for the enhanced removal of anionic pollutants by electrokinetic remediation
Genetic polymorphism of merozoite surface protein-1 and merozoite surface protein-2 in Plasmodium falciparum field isolates from Myanmar
<p>Abstract</p> <p>Background</p> <p>Merozoite surface protein-1 (MSP-1) and MSP-2 of <it>Plasmodium falciparum </it>are potential vaccine candidate antigens for malaria vaccine development. However, extensive genetic polymorphism of the antigens in field isolates of <it>P. falciparum </it>represents a major obstacle for the development of an effective vaccine. In this study, genetic polymorphism of MSP-1 and MSP-2 among <it>P. falciparum </it>field isolates from Myanmar was analysed.</p> <p>Methods</p> <p>A total of 63 <it>P. falciparum </it>infected blood samples, which were collected from patients attending a regional hospital in Mandalay Division, Myanmar, were used in this study. The regions flanking the highly polymorphic characters, block 2 for MSP-1 and block 3 for MSP-2, were genotyped by allele-specific nested-PCR to analyse the population diversity of the parasite. Sequence analysis of the polymorphic regions of MSP-1 and MSP-2 was also conducted to identify allelic diversity in the parasite population.</p> <p>Results</p> <p>Diverse allelic polymorphism of MSP-1 and MSP-2 was identified in <it>P. falciparum </it>isolates from Myanmar and most of the infections were determined to be mixed infections. Sequence analysis of MSP-1 block 2 revealed that 14 different alleles for MSP-1 (5 for K1 type and 9 for MAD20 type) were identified. For MSP-2 block 3, a total of 22 alleles (7 for FC27 type and 15 for 3D7 type) were identified.</p> <p>Conclusion</p> <p>Extensive genetic polymorphism with diverse allele types was identified in MSP-1 and MSP-2 in <it>P. falciparum </it>field isolates from Myanmar. A high level of mixed infections was also observed, as was a high degree of multiplicity of infection.</p
Comparison of the antibody responses to Plasmodium vivax and Plasmodium falciparum antigens in residents of Mandalay, Myanmar
<p>Abstract</p> <p>Background</p> <p>The aim of this study was to investigate the profile of antibodies against several antigens of <it>Plasmodium vivax </it>and <it>Plasmodium falciparum </it>in Mandalay, Myanmar.</p> <p>Methods</p> <p>Malaria parasites were identified by microscopic examination. To test the antibodies against <it>P. vivax </it>and <it>P. falciparum </it>in sera, an indirect immunofluorescence antibody test (IFAT) was performed using asexual blood parasite antigens. An enzyme-linked immunosorbent assay (ELISA) was performed with circumsporozoite protein (CSP), Pvs25 and Pvs28 recombinant proteins of transmission-blocking vaccine candidates for <it>P. vivax</it>, and liver stage specific antigen-1 and -3 (PfLSA-1, PfLSA-3) for <it>P. falciparum</it>.</p> <p>Results</p> <p>Fourteen patients among 112 were found to be infected with <it>P. vivax </it>and 26 with <it>P. falciparum </it>by thick smear examination. Twenty-three patients were found to be infected with <it>P. vivax</it>, 19 with <it>P. falciparum </it>and five with both by thin smear examination. Blood samples were divided into two groups: Group I consisted of patients who were positive for infection by microscopic examination, and Group II consisted of those who showed symptoms, but were negative in microscopic examination. In <it>P. falciparum</it>, IgG against the blood stage antigen in Group I (80.8%) was higher than in Group II (70.0%). In <it>P. vivax</it>, IgG against the blood stage antigen in Group I (53.8%) was higher than in Group II (41.7%). However, the positivity rate of the PvCSP VK210 subtype in Group II (40.0%) was higher than in Group I (23.1%). Similarly for the PvCSP VK247 subtype, Group II (21.7%) was higher than that for Group I (9.6%). A similar pattern was observed in the ELISA using Pvs25 and Pvs28: positive rates of Group II were higher than those for Group I. However, those differences were not shown significant in statistics.</p> <p>Conclusions</p> <p>The positive rates for blood stage antigens of <it>P. falciparum </it>were higher in Group I than in Group II, but the positive rates for antigens of other stages (PfLSA-1 and -3) showed opposite results. Similar to <it>P. falciparum</it>, the positive rate of pre-blood stage (CSP VK210 and 247 subtype) and post-blood stage (Pvs25 and 28) antigens of <it>P. vivax </it>were higher in Group II than in Group I. Therefore, sero-diagnosis is not helpful to discriminate between malaria patients and symptomatic individuals during the epidemic season in Myanmar.</p
Molecular Cloning of Plasmodium vivax Calcium-Dependent Protein Kinase 4
A family of calcium-dependent protein kinases (CDPKs) is a unique enzyme which plays crucial roles in intracellular calcium signaling in plants, algae, and protozoa. CDPKs of malaria parasites are known to be key regulators for stage-specific cellular responses to calcium, a widespread secondary messenger that controls the progression of the parasite. In our study, we identified a gene encoding Plasmodium vivax CDPK4 (PvCDPK4) and characterized its molecular property and cellular localization. PvCDPK4 was a typical CDPK which had well-conserved N-terminal kinase domain and C-terminal calmodulin-like structure with 4 EF hand motifs for calcium-binding. The recombinant protein of EF hand domain of PvCDPK4 was expressed in E. coli and a 34 kDa product was obtained. Immunofluorescence assay by confocal laser microscopy revealed that the protein was expressed at the mature schizont of P. vivax. The expression of PvCDPK4-EF in schizont suggests that it may participate in the proliferation or egress process in the life cycle of this parasite
Conditioned media from AICAR-treated skeletal muscle cells increases neuronal differentiation of adult neural progenitor cells
Exercise has profound benefits for brain function in animals and humans. In rodents, voluntary wheel running increases the production of new neurons and upregulates neurotrophin levels in the hippocampus, as well as improving synaptic plasticity, memory function and mood. The underlying cellular mechanisms, however, remain unresolved. Recent research indicates that peripheral organs such as skeletal muscle, liver and adipose tissue secrete factors during physical activity that may influence neuronal function. Here we used an in vitro cell assay and proteomic analysis to investigate the effects of proteins secreted from skeletal muscle cells on adult hippocampal neural progenitor cell (aNPC) differentiation. We also sought to identify the relevant molecules driving these effects. Specifically, we treated rat L6 skeletal muscle cells with the AMP-kinase (AMPK) agonist 5-aminoimidazole-4-carboxamide-1-beta-D-ribofuranoside (AICAR) or vehicle (distilled water). We then collected the conditioned media (CM) and fractionated it using high-performance liquid chromatography (HPLC). Treatment of aNPCs with a specific fraction of the AICAR-CM upregulated expression of doublecortin (DCX) and Tuj1, markers of immature neurons. Proteomic analysis of this fraction identified proteins known to be involved in energy metabolism, cell migration, adhesion and neurogenesis. Culturing differentiating aNPCs in the presence of one of the factors, glycolytic enzyme glucose-6-phosphate isomerase (GPI), or AICAR-CM, increased the proportion of neuronal (Tuj1(+)) and astrocytic, glial fibrillary acidic protein (GFAP(+)) cells. Our study provides further evidence that proteins secreted from skeletal muscle cells may serve as a critical communication link to the brain through factors that enhance neural differentiation.OAIID:RECH_ACHV_DSTSH_NO:T201812496RECH_ACHV_FG:RR00200001ADJUST_YN:EMP_ID:A080443CITE_RATE:4.249DEPT_NM:체육교육과EMAIL:[email protected]_YN:YN
Study of Chemical Substances Emitted during Paint Manufacturing through VOC Speciation
Volatile organic compounds (VOCs) emitted from the paint manufacturing industry include substances that are highly volatile, such as toluene, and highly carcinogenic, such as benzene. In the Republic of Korea, the emission of volatile organic compounds is regulated under the Clean Air Conservation Act, but it is found that individual substances are systematically insufficient. Although the Pollutant Release and Transfer Register (PRTR) is maintained to report the expected emissions from each plant every year, actual measurements are not performed. This study measured and analyzed VOCs at the site fenceline boundary. The ratio of PRTR and VOCs speciation results for xylene and toluene was similar to that of xylene 29% and toluene 28%, but ethylbenzene accounted for 2% in PRTR. Still, the actual measurement result showed a big difference of 11%. Because it is a solvent that is treated in large quantities in the resin manufacturing process and the reactivity of ethylbenzene, it is vaporized at high temperature and high pressure, resulting in many measurements. This study classified a large amount of VOCs emitted through the fence line monitoring system in the paint manufacturing industry and confirmed which VOCs were emitted the most. We compared whether this produced similar results to the actual emission survey method conducted by the EPA. Some substances have produced similar results, but certain substances have significant differences. This indicates that priority VOCs should be selected for each location through continuous measurement