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Extensive application of carbon quantum dots (CQDs) enlarges its concentration in sewage treatment system. The response of nitrifying sludge to CQDs after long-term exposure was investigated. Results showed that CQD concentrations of 0-100 mg/L presented positive effect to enzymes involved in nitrification, accelerating NH4+-N degradation and NO2--N transformation. The oxidation rate of NO2--N was significantly improved from 3.14 to 7.91 mg/(L h) under the stress of 100 mg/L CQDs. Besides, CQDs stimulated the production of sludge biomass and kept the stability of sludge settleability. Additionally, CQDs were mainly captured by loosely bound extracellular polymeric substances, reducing aromatic-like protein. Microbes alleviated CQD stress by secreting tryptophan-like protein and polysaccharides. After few CQDs entered cells, intracellular antioxidant defense was activated. Total antioxidant capacity level was heightened at least 31%. The activities of superoxide dismutase and catalase were enhanced at relatively low and high CQD concentration levels. Hence, microbial metabolic pathways, microbial community, and nitrifying bacteria were not significantly affected by CQDs. The findings of this work provide new insight for understanding the environmental implication of CQDs in the biological treatment system.
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Pontos Quânticos , Esgotos , Esgotos/microbiologia , Antioxidantes , Dióxido de Nitrogênio , Reatores Biológicos/microbiologia , Nitrificação , CarbonoRESUMO
In this work, we investigated the potential UV protection mechanism of the natural compounds hydroxy resveratrol and pterostilbene by combining theoretical calculations and femtosecond transient absorption spectra (FTAS). The UV absorption spectra showed that the two compounds exhibited strong absorption properties and high photostability. We found two molecules will reach the S1 state or an even higher excited state after UV exposure and molecules in S1 will cross a lower energy barrier to reach the conical intersection. The adiabatic trans-cis isomerization process happened and finally return to the ground. Meanwhile, FTAS clarified the time scale of trans-cis isomerization of two molecules was â¼ 10 ps, which also met the requirement of fast energy relaxation. This work also provides theoretical guidance for developing new sunscreen molecules from natural stilbene.
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Because of the massive discharge of nitrogenous wastewater, the eutrophication of a water body is becoming increasingly serious, and how to effectively remove nitrogen from this wastewater remains an urgent problem to be solved. In this study, due to disadvantages in the traditional biological nitrogen removal process, such as complex and long procedures, high energy consumption, weak impact resistance, and N2O release, the nitrogen removal theory by heterotrophic nitrification was further analyzed by discussing the physiological-biochemical, heterotrophic nitrification-aerobic denitrification, and N2O production characteristics of a high-efficiency heterotrophic nitrifying bacteria Pseudomonas aeruginosa YL. Results show that the strain YL had an eminent heterotrophic nitrification and aerobic denitrification ability, and NH4+-N, NO2--N, and NO3--N with concentration of 100 mg·L-1 could be completely removed during the 24-hour incubation period. There was almost no intermediate product in the process of heterotrophic nitrification, however when NO3--N was used as nitrogen source, the accumulation of NO2--N reached 25.55 mg·L-1. Meanwhile, the successful expression of denitrification genes napA, nirK, and nosZ further confirmed the aerobic denitrification ability of strain YL. Gaseous nitrogen products accounted for about 30%-40% of removed TN in the heterotrophic nitrification-aerobic denitrification process by strain YL, and N2 was the main denitrification product. When NH4+-N, NO2--N, and NO3--N were used as the sole nitrogen source, N2 production amounted to 3.46, 3.49, and 3.36 mg, respectively. In contrast, only small amounts of N2O were produced in the denitrification process by strain YL, and the total amount was 6.63 µg when NH4+-N was the nitrogen source, which was much lower than in the cases of NO2--N and NO3--N as the sole nitrogen source. In addition, high C/N, low pH, high temperature, high NH4+-N, and high NO2--N conditions could result in more N2O generation. Nevertheless, most environmental factors had little effect on N2O production of strain YL, and the maximum N2O production was significantly lower than that of short-cut nitrification system and autotrophic nitrification system. These results demonstrated that strain YL exhibited excellent abilities of nitrogen removal, N2O emission control, and tolerance to environmental conditions, and could be an effective candidate for treating wastewater without secondary air pollution.
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Desnitrificação , Processos Heterotróficos , Nitritos/metabolismo , Pseudomonas aeruginosa/fisiologia , Aerobiose , Genes Bacterianos , Nitrificação , Nitrogênio/metabolismoRESUMO
OBJECTIVE: Gandouling (GDL) tablet is a Chinese patent medicine approved by the National Medical Product Administration, which is used to treat Wilson disease (WD) in China. In this study, we aimed to investigate the effects of GDL on mitophagy in the hippocampus in the toxic milk (TX) mouse model of WD. METHODS: Mice were randomly divided into the following four groups: control, Wilson (model group), D-penicillamine (DPA), and GDL groups. The animal behaviors were evaluated by the water maze experiment, traction test, and pole test. Transmission electron microscopy was used for the detection of mitochondrion structure. An enzyme-linked immunosorbent assay (ELISA) was performed for the analysis of the changes in liver function. Colocalization of mitophagy-related proteins was detected by fluorescence microscopy. Western blotting (WB) and reverse transcription-polymerase chain reaction (RT-PCR) were conducted for the detection of protein expression and mRNA levels, respectively. RESULTS: Significant reduction in neurological impairments was observed in the WD model group. All of these results were significantly reversed by GDL intervention. Compared with the levels in the Wilson group, the levels of alanine aminotransferase (ALT), aspartate transaminase (AST), total bilirubin (TBIL), and albumin (ALB) changed obviously. Colocalization between mitophagy-related proteins pink1, parkin, and mitochondria was changed significantly. The mitophagy-related mRNA (pink1, parkin, and LC3II) and protein expression levels (pink1, parkin, and the rate of LC3II/LC3I) were decreased significantly, while p62 was remarkably increased after GDL intervention. CONCLUSION: Our findings indicated that the neuroprotective mechanism of GDL may occur via the inhibition of excessive mitophagy through the regulation of the pink1/parkin pathway in the TX mouse brain of WD.
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Natural UV photoprotection plays a vital role in physiological protection. It has been reported that UVC radiation can make resveratrol (RSV) and piceatannol (PIC) accumulate in grape skin. In this work, we demonstrated that RSV and PIC could significantly absorb UVA and UVB, and confirmed their satisfactory photostability. Furthermore, we clarified the UV photoprotection mechanism of typical stilbenoids of RSV and PIC for the first time by using combined femtosecond transient absorption (FTA) spectroscopy and time-dependent density functional theory (TD-DFT) calculations. RSV and PIC can be photoexcited to the excited state after UVA and UVB absorption. Subsequently, the photoisomerized RSV and PIC quickly relax to the ground state via nonadiabatic transition from the S1 state at a conical intersection (CI) position between potential energy surfaces (PESs) of S1 and S0 states. This ultrafast trans-cis photoisomerization will take place within a few tens of picoseconds. As a result, the UV energy absorbed by RSV and PIC could be dissipated by an ultrafast nonadiabatic photoisomerization process.
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Frutas/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Resveratrol/farmacologia , Estilbenos/farmacologia , Vitis/efeitos dos fármacos , Teoria da Densidade Funcional , Estrutura Molecular , Processos Fotoquímicos , Substâncias Protetoras/química , Resveratrol/química , Estereoisomerismo , Estilbenos/química , Raios UltravioletaRESUMO
OBJECTIVE: To retrospectively analyze the experiences, indications, technique, and results of coronary artery bypass grafting (CABG) in patients over 70 years old. METHODS: Ninety-one patients received coronary artery bypass grafting from March 2004 to March 2008. Ages ranged from 70 to 83 years old, 22 patients over 75 years old. Conventional CABG (CCABG) in 72 patients, off-pump CABG (OPCAB) in 19 patients. Clinical data has no significant differences in two groups. The rate of using left internal mammary artery was 96.7%. The number of grafts in CCABG and OPCAB group were 2 to 5 (3.5 +/- 0.8) and 1 to 4 (2.9 +/- 0.7) respectively. RESULTS: In-hospital death in 2 cases, both were from chronic obstructive pulmonary disease and pulmonary infection. Cerebral infarction in 1 case and pulmonary infection in 2 cases in CCABG group, but no significant difference between two groups, and no difference in intubation, ICU stay, respiratory failure, renal function failure. But number of grafts in CCABG was significantly more than that in OPCAB (P < 0.01). Postoperative follow-up was 3 to 36 months, 1 case with recurrent angina in OPCAB. CONCLUSIONS: According to the characteristic of coronary artery disease in elderly, fully revascularization and improving myocardial blood supply, patients over 70 years old with CABG can obtain the same efficacy as younger patients. There were not significant difference between CCABG and OPCAB.
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Ponte de Artéria Coronária/métodos , Idoso , Idoso de 80 Anos ou mais , Ponte de Artéria Coronária sem Circulação Extracorpórea , Doença das Coronárias/cirurgia , Feminino , Humanos , Masculino , Estudos Retrospectivos , Resultado do TratamentoRESUMO
Due to the low nitrogen removal efficiency, lengthy procedure, and vulnerability to high loads of ammonium of the traditional sewage treatment process, the physiological characteristics, nitrogen removal characteristics, influencing factors, and kinetic analysis were systematically studied for the heterotrophic nitrifier Pseudomonas putida YH, which has efficient nitrogen removal ability. The results showed that strain YH exhibited efficient heterotrophic nitrification ability with a low accumulation of nitrification products. The maximum ammonium removal rate was 99.1%, and nearly 53% of the removed TN was converted to intracellular nitrogen. In addition, nitrite and nitrate could also be metabolized by strain YH under aerobic conditions, with a maximum removal rate of 99.8% and 99.5%, respectively. Additionally, the successful PCR amplification of the napA and nirK genes further improved the aerobic denitrification characteristics of strain YH. The bacterial growth process of strain YH matched the Logistic model (R2>0.99), and the nitrogen degradation conformed to the Compertz model (R2>0.99). The order of the maximum conversion rates of nitrogen (Rm) was ammonia > nitrate > nitrite, and that of the lag time (t0) was nitrate > nitrite > ammonia. The optimal conditions for heterotrophic ammonium oxidation with strain YH were succinate as the carbon source, C/N=10, T=30â, r=160-200 r·min-1, and pH=7.0. Under the optimal conditions, the average ammonia oxidation rate and Rm were 8.35 and 16.71 mg·(L·h)-1, respectively. Strain YH could adapt to a broad range of ammonium loads. A high ammonium removal rate was observed under high ammonium concentrations (1000 mg·L-1), indicating the high potential of strain YH for application in high-strength ammonium wastewater treatment.
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Compostos de Amônio/metabolismo , Desnitrificação , Nitrogênio/isolamento & purificação , Pseudomonas putida/metabolismo , Aerobiose , Genes Bacterianos , Processos Heterotróficos , Cinética , Nitrificação , NitritosRESUMO
Due to the problems of traditional biological nitrogen and phosphorus removal, including long process duration and high infrastructural and operational costs, the simultaneous nitrogen and phosphorus removal capabilities, influencing factors and kinetic characteristics were systematically studied using the heterotrophic nitrifier Acinetobacter junii NP1 which possesses efficient simultaneous nitrogen and phosphorus removal ability. The results showed that strain NP1 exhibited efficient heterotrophic nitrification ability with a maximum ammonia removal rate of 99.12%. Furthermore, only small amounts of nitrification intermediates were accumulated during the reaction process. Strain NP1 also adapted well to higher ammonia nitrogen loading. In addition, strain NP1 had efficient aerobic denitrification characteristics, and could utilize nitrite and nitrate for growth and metabolism, achieving a maximum removal rate of 91.40% and 95.10%, respectively. The heterotrophic nitrification process of strain NP1 was accompanied by simultaneous phosphorus accumulation, and the appropriate ratio of nitrogen to phosphorus was beneficial for the simultaneous removal of nitrogen and phosphorus. When the ratio of nitrogen to phosphorus was 5:1, the maximum ammonia nitrogen and phosphate removal rates reached 99.21% and 88.35%, respectively. The bacterial growth process of stain NP1 matched the Logistic model (R2>0.99), and the nitrogen and phosphate degradation conformed to the Compertz model (R2>0.99). The maximum conversion rates of nitrogen and phosphate (Rm) obtained by model fitting were in the order ammonia>nitrate>nitrite, and lag time (t0) was in the order nitrate>nitrite>ammonia. According to the analysis of the degradation kinetics of the matrix and the removal rate of nitrogen and phosphorus, the optimal conditions were found to be sodium succinate, C/N=10, T=30â, and r=160 r·min-1.
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Acinetobacter , Nitrogênio , Fósforo , Purificação da Água , Acinetobacter/metabolismo , Aerobiose , Desnitrificação , Processos Heterotróficos , Cinética , Nitrificação , NitritosRESUMO
A novel strain NP5 with efficient heterotrophic nitrification, aerobic denitrification and phosphorus accumulation ability was isolated and identified as Pseudomonas putida strain NP5. The removed ammonium and phosphate were mainly converted into intracellular components by assimilation, and negligible nitrification intermediates and N2O were accumulated during heterotrophic nitrification. In addition, the optimal conditions for nutrient removal were: succinate as carbon source, C/N 10, P/N 0.2, temperature 30⯰C, salinity 0% and shaking speed 160â¯rpm. Besides, strain NP5 possessed an exceptional heavy metal and nanoparticles resistance. Cr6+ was found to be the most toxic among the tested metals, and it could be removed simultaneously. Moreover, an obvious phosphorus release was observed under anaerobic condition, and repeated exposure to the anaerobic/aerobic conditions could significantly improve the nutrient removal. Furthermore, the successful expression of key enzymes for nitrogen and phosphorous removal provided additional evidence for possibility of simultaneous nitrification, denitrification and phosphorus removal.
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Nitrificação , Pseudomonas putida , Aerobiose , Desnitrificação , Processos Heterotróficos , Metais , Nitritos , Nitrogênio , FósforoRESUMO
Redox balance, an essential feature of healthy physiological steady states, is regulated by circadian clocks, but whether or how endogenous redox signalling conversely regulates clockworks in mammals remains unknown. Here, we report circadian rhythms in the levels of endogenous H2O2 in mammalian cells and mouse livers. Using an unbiased method to screen for H2O2-sensitive transcription factors, we discovered that rhythmic redox control of CLOCK directly by endogenous H2O2 oscillations is required for proper intracellular clock function. Importantly, perturbations in the rhythm of H2O2 levels induced by the loss of p66Shc, which oscillates rhythmically in the liver and suprachiasmatic nucleus (SCN) of mice, disturb the rhythmic redox control of CLOCK function, reprogram hepatic transcriptome oscillations, lengthen the circadian period in mice and modulate light-induced clock resetting. Our findings suggest that redox signalling rhythms are intrinsically coupled to the circadian system through reversible oxidative modification of CLOCK and constitute essential mechanistic timekeeping components in mammals.
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Relógios Circadianos/fisiologia , Ritmo Circadiano/fisiologia , Peróxido de Hidrogênio/metabolismo , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src/metabolismo , Animais , Feminino , Fígado/metabolismo , Fígado/fisiologia , Masculino , Mamíferos/metabolismo , Mamíferos/fisiologia , Camundongos , Camundongos Knockout , Oxirredução , Proteínas Circadianas Period/metabolismo , Transdução de Sinais/fisiologia , Núcleo Supraquiasmático/metabolismo , Núcleo Supraquiasmático/fisiologiaRESUMO
Laboratory experimentation was used to investigate the impact of the organic loading rate shock on extracellular polymeric substances (EPSs) and the physicochemical characteristics of nitrifying sludge (NS) treating high-strength ammonia wastewater. The increased organic loading rates (OLRs) strongly influenced the stability of the NS with regard to nutrient removal, biomass-liquid separation, and surface properties, leading to the sludge system collapse at the OLR of 0.75 kg COD per kg MLVSS d. However, an incomplete recovery of the NS after the high OLRs shock was observed when decreasing the OLRs. In addition, the variations of OLRs resulted in relatively stable amounts of tightly bound EPS (TB-EPS), but a significant change in loosely bound EPS (LB-EPS). Both in LB-EPS and TB-EPS, the proteins (PN) contents and proteins to polysaccharides (PN/PS) ratios decreased with the increase in OLRs. Results from the excitation emission matrix spectra implied that the tryptophan PN-like substances were the major components in EPS at low OLRs, while the humic acid-like and fulvic acid-like substrates increased markedly at high OLRs. Furthermore, correlation analysis demonstrated that PN and the PN/PS ratio were the most important factors in determining the physicochemical properties of the NS. It was indicated that the PN could accurately reflect the sludge properties of the NS, and thus effectively change the surface properties of the sludge, contributing to the cohesion between the aggregates to maintain a stable structure.
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Accumulating data from genome-wide association studies (GWAS) have provided a collection of novel candidate genes associated with complex diseases, such as atherosclerosis. We identified an atherosclerosis-associated single-nucleotide polymorphism (SNP) located in the intron of the long noncoding RNA (lncRNA) LINC00305 by searching the GWAS database. Although the function of LINC00305 is unknown, we found that LINC00305 expression is enriched in atherosclerotic plaques and monocytes. Overexpression of LINC00305 promoted the expression of inflammation-associated genes in THP-1 cells and reduced the expression of contractile markers in co-cultured human aortic smooth muscle cells (HASMCs). We showed that overexpression of LINC00305 activated nuclear factor-kappa beta (NF-κB) and that inhibition of NF-κB abolished LINC00305-mediated activation of cytokine expression. Mechanistically, LINC00305 interacted with lipocalin-1 interacting membrane receptor (LIMR), enhanced the interaction of LIMR and aryl-hydrocarbon receptor repressor (AHRR), and promoted protein expression as well as nuclear localization of AHRR. Moreover, LINC00305 activated NF-κB exclusively in the presence of LIMR and AHRR. In light of these findings, we propose that LINC00305 promotes monocyte inflammation by facilitating LIMR and AHRR cooperation and the AHRR activation, which eventually activates NF-κB, thereby inducing HASMC phenotype switching.
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Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Inflamação/genética , Inflamação/patologia , Monócitos/metabolismo , Monócitos/patologia , NF-kappa B/metabolismo , RNA Longo não Codificante/metabolismo , Proteínas Repressoras/metabolismo , Aorta/patologia , Aterosclerose/genética , Aterosclerose/patologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Linhagem Celular , Núcleo Celular/metabolismo , Estudo de Associação Genômica Ampla , Humanos , Miócitos de Músculo Liso/metabolismo , Fenótipo , Transporte Proteico , RNA Longo não Codificante/genética , Receptores de Superfície Celular/metabolismo , Proteínas Repressoras/genética , Transdução de Sinais/genética , Regulação para CimaRESUMO
Cardiac hypertrophy is the strongest predictor of the development of heart failure, and anti-hypertrophic treatment holds the key to improving the clinical syndrome and increasing the survival rates for heart failure. The paraoxonase (PON) gene cluster (PC) protects against atherosclerosis and coronary artery diseases. However, the role of PC in the heart is largely unknown. To evaluate the roles of PC in cardiac hypertrophy, transgenic mice carrying the intact human PON1, PON2, and PON3 genes and their flanking sequences were studied. We demonstrated that the PC transgene (PC-Tg) protected mice from cardiac hypertrophy induced by Ang II; these mice had reduced heart weight/body weight ratios, decreased left ventricular wall thicknesses and increased fractional shortening compared with wild-type (WT) control. The same protective tendency was also observed with an Apoe -/- background. Mechanically, PC-Tg normalized the disequilibrium of matrix metalloproteinases (MMPs)/tissue inhibitors of MMPs (TIMPs) in hypertrophic hearts, which might contribute to the protective role of PC-Tg in cardiac fibrosis and, thus, protect against cardiac remodeling. Taken together, our results identify a novel anti-hypertrophic role for the PON gene cluster, suggesting a possible strategy for the treatment of cardiac hypertrophy through elevating the levels of the PON gene family.