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1.
Water Sci Technol ; 86(10): 2483-2494, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36450668

RESUMO

Vitamin (VM) tablets are often discarded or incinerated as medical waste, and untreated highly chlorinated wastewater is discharged, polluting the environment. In this study, Cu2+ was reduced by vitamin C (VC, a component of VM), and the precipitate formed by the reaction of its product with Cl- in water was used to remove Cl- from simulated wastewater. This allows for the resourceful use of waste VM, while also achieving the goal of dechlorinating wastewater. Meanwhile, the effect of various parameters on dechlorination was studied, and the dechlorination mechanism was analyzed. According to the results, the removal rate of Cl- increased first and then decreased with pH, removal time and reaction temperature. Using VC in VM to dechlorinate simulated wastewater, the removal rate of Cl- was 94.31% under optimum conditions: pH 2.5, temperature 30 °C and reaction time 10 minutes. According to the dechlorination process, it can be inferred that Cu2+ is reduced to Cu+ by VC, and Cu+ and Cl- coprecipitate to remove Cl-. Therefore, it is feasible to use discarded VM to treat high concentration chlorine-containing wastewater.


Assuntos
Cloretos , Águas Residuárias , Vitaminas , Comprimidos , Ácido Ascórbico
2.
ACS Infect Dis ; 8(5): 998-1009, 2022 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-35362944

RESUMO

Cerebral malaria (CM) is a serious central nervous system dysfunction caused by Plasmodium falciparum infection. In this study, we investigated the effect of Listeria monocytogenes (Lm) inoculation on experimental cerebral malaria (ECM) using Plasmodium berghei ANKA (PbA)-infected C57BL/6 mice. Live Lm inoculation inhibited the parasitemia and alleviated ECM symptoms. The protective effect against ECM symptoms was connected with improved brain pathology manifested as a less-damaged blood-brain barrier, decreased parasite sequestration, and milder local inflammation. Meanwhile, Lm inoculation decreased expression of cell adhesion molecules (ICAM-1 and VCAM-1) and accumulation of pathogenic CD8+ T cells in the brain. In keeping with the suppression of parasitemia, there was an upregulation of IFN-γ, IL-12, MCP-1, and NO expression in the spleen by Lm inoculation upon PbA infection. Early treatment with exogenous IFN-γ exhibited a similar effect to Lm inoculation on PbA infection. Taken together, Lm inoculation impedes the development of brain pathology in ECM, and early systemic IFN-γ production may play a critical role in these protective effects.


Assuntos
Listeria monocytogenes , Malária Cerebral , Animais , Encéfalo , Linfócitos T CD8-Positivos/parasitologia , Linfócitos T CD8-Positivos/patologia , Malária Cerebral/parasitologia , Malária Cerebral/patologia , Camundongos , Camundongos Endogâmicos C57BL , Parasitemia/patologia , Plasmodium berghei
3.
Syst Appl Microbiol ; 45(1): 126280, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34864282

RESUMO

Chamaecrista mimosoides is an annual herb legume widely distributed in tropical and subtropical Asia and Africa. It may have primitive and independently-evolved root nodule types but its rhizobia have not been systematically studied. Therefore, in order to learn the diversity and species affinity of its rhizobia, root nodules were sampled from C. mimosoides plants growing in seven geographical sites along the coast line of Shandong Peninsula, China. A total of 422 rhizobial isolates were obtained from nodules, and they were classified into 28 recA haplotypes. By using multilocus sequence analysis of the concatenated housekeeping genes dnaK, glnII, gyrB, recA and rpoB, the representative strains for these haplotypes were designated as eight defined and five candidate novel genospecies in the genus Bradyrhizobium. Bradyrhizobium elkanii and Bradyrhizobium ferriligni were predominant and universally distributed. The symbiotic genes nodC and nifH of the representative strains showed very similar topology in their phylogenetic trees indicating their co-evolution history. All the representative strains formed effective root nodules in nodulation tests. The correlation between genospecies and soil characteristics analyzed by CANOCO software indicated that available potassium (AK), organic carbon (OC) and available nitrogen (AN) in the soil samples were the main factors affecting the distribution of the symbionts involved in this current study. The study is the first systematic survey of Chamaecrista mimosoides-nodulating rhizobia, and it showed that Chamaecrista spp. were nodulated by bradyrhizobia in natural environments. In addition, the host spectrum of the corresponding rhizobial species was extended, and the study provided novel information on the biodiversity and biogeography of rhizobia.


Assuntos
Bradyrhizobium , Chamaecrista , Rhizobium , Biodiversidade , Bradyrhizobium/genética , DNA Bacteriano/genética , Filogenia , RNA Ribossômico 16S/genética , Rhizobium/genética , Nódulos Radiculares de Plantas , Análise de Sequência de DNA , Simbiose
4.
Front Microbiol ; 12: 665839, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34017318

RESUMO

Vigna minima is a climbing annual plant widely distributed in barren wilderness, grass land, and shrub bush of China and other countries such as Japan. However, the rhizobia nodulating with this plant has never been systematically studied. In order to reveal the biodiversity of nodulating rhizobia symbiosis with V. minima, a total of 874 rhizobium isolates were obtained from root nodules of the plant spread in 11 sampling sites of Shandong Peninsula, China, and they were designated as 41 haplotypes in the genus Bradyrhizobium based upon recA sequence analyses. By multilocus sequence analysis (MLSA) of five housekeeping genes (dnaK, glnII, gyrB, recA, and rpoB), the 41 strains representing different recA haplotypes were classified into nine defined species and nine novel genospecies. Bradyrhizobium elkanii, Bradyrhizobium ferriligni, and Bradyrhizobium pachyrhizi were the predominant and universally distributed groups. The phylogeny of symbiotic genes of nodC and nifH showed similar topology and phylogenetic relationships, in which all the representative strains were classified into two clades grouped with strains nodulating with Vigna spp., demonstrating that Vigna spp. shared common nodulating groups in the natural environment. All the representative strains formed nodules with V. minima in a nodulation test performed in green house conditions. The correlation between V. minima nodulating rhizobia and soil characteristics analyzed by CANOCO indicates that available nitrogen, total nitrogen, and organic carbon in the soil samples were the main factors affecting the distribution of rhizobia isolated in this study. This study systematically uncovered the biodiversity and distribution characteristics of V. minima nodulating rhizobia for the first time, which provided novel information for the formation of the corresponding rhizobium community.

5.
Water Sci Technol ; 83(9): 2232-2241, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33989189

RESUMO

Precipitation dechlorination has the advantage of being a simple process with a low cost. However, there are few reports on the effect of cations on dechlorination. In this study, we investigated the effect of cations in high-salt wastewater on the removal of chlorine ions by cuprous chloride precipitation and analysed the corresponding mechanism. A series of investigations revealed that Fe3+ could oxidise sulphite, thereby reducing the removal rate of chlorine ions. The reaction between magnesium and sulphite results in precipitation, which has a slightly adverse effect on the removal of chloride ions. Hexavalent chromium oxidises the chloride ion, resulting in the formation of chlorine gas, which improves the removal rate. Ferrous and manganese, however, do not have a notable effect on chlorine removal.


Assuntos
Cloro , Águas Residuárias , Cátions , Cloretos , Cloreto de Sódio
6.
Huan Jing Ke Xue ; 37(8): 2855-2862, 2016 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-29964708

RESUMO

Robust measures were taken to ensure a good air quality for the parade on the 70th Victory Memorial Day for the Chinese People's War of Resistance against Japanese Aggression (VM Day). During the period, the source of fine particulate matter in air was analyzed with the single particle aerosol mass spectrometer (SPAMS) located at Shijiazhuang air automatic monitoring station of 20 meter. The results indicated that, on VM Day the primary sources of air pollution were vehicle exhaust emission (20.9%) and coal-generated emissions (20.6%), which were also at lower degrees than those on pre-and post-VM Day. It turned out that these air quality-improving measures, especially the vehicle restriction and coal consumption reduction, had a good effect. Particles from the vehicle exhaust and coal combustion source were mainly based on short-chain elements, carbon, manganese and organic carbon. The particles from the industry source were mainly organic carbon and metal. Particles from the dust source were mainly composed of silicate and calcium. When air quality-improving measures were stopped, the concentration of particulate matter rapidly rose again, and the contribution of dust and vehicle exhaust emission was remarkable. It was believed that the interaction of low-pressure static stability of adverse weather conditions and southeast direction of low altitude transmission was a major cause in the deterioration of air quality.

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