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1.
Sci Total Environ ; 750: 141513, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32853935

RESUMO

Excessive nitrate in water systems is prevailing and a global risk of human health. Polluted river sediments are dominated by anaerobes and often the hotspot of denitrification. So far, little is known about the ecological effects of nitrate pollution on microbial dynamics, especially those in sulfide-rich sediments. Here we simulated a nitrate surge and monitored the microbial responses, as well as the changes of important environmental parameters in a sulfide-rich river sediment for a month. Our analysis of sediment microbial communities showed that elevated nitrate led to (i) a functional convergence at denitrification and sulfide oxidation, (ii) a taxonomic convergence at Proteobacteria, and (iii) a significant loss of biodiversity, community stability and other functions. Two chemolithotrophic denitrifiers Thiobacillus and Luteimonas were enriched after nitrate amendment, although the original communities were dominated by methanogens and syntrophic bacteria. Also, serial dilutions of sediment microbial communities found that Thiobacillus thiophilus dominated 18/30 communities because of its capability of simultaneous nitrate reduction and sulfide oxidation. Additionally, our network analysis indicated that keystone taxa seemed more likely to be native auxotrophs (e.g., syntrophic bacteria, methanogens) rather than dominant denitrifiers, possibly because of the extensive interspecific cross-feeding they estabilished, while environment perturbations probably disrupted that cross-feeding and simplified microbial interactions. This study advances our understanding of microbial community responses to nitrate pollution and possible mechanism in the sulfide-rich river sediment.


Assuntos
Microbiota , Rios , Desnitrificação , Sedimentos Geológicos , Nitratos , Sulfetos , Thiobacillus
2.
Pharmacology ; 105(9-10): 505-513, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32784309

RESUMO

OBJECTIVE: This research was aimed to explore protective effects of allicin on rat model of myocardial infarction via JNK signaling pathway. METHODS: Rat myocardial ischemia model was established with subcutaneous injection of isoproterenol (ISO). Seventy-five rats were randomly divided into 5 groups (n = 15): sham group, ISO group, low-dose group (1.2 mg/kg/days for 7 days), medium-dose group (1.8 mg/kg/days for 7 days), and high-dose group (3.6 mg/kg/days for 7 days). Routine HE staining and Masson staining were performed to observe myocardial histopathology. The expression of oxidative stress-related indicators, heart tissue apoptosis-related proteins, and JNK and p-JNK proteins were measured for different groups. RESULTS: Compared with the sham group, the T wave value of the ISO group was significantly increased (p < 0.01). When allicin was administered, the T wave values at different time points in all groups were all decreased. Compared with the sham group, the ratio of eNOS, Bcl-2/Bax was significantly decreased, and p-eNOS, iNOS, caspase-3, caspase-9, and Cyt-c were significantly elevated in the ISO group (p < 0.05). After allicin was administered, significant changes in these proteins were observed in the medium- and high-dose groups. There was no significant change in the expression of JNK protein in the ISO group compared with the sham group; however, the expression of eNOS and p-JNK protein were significantly upregulated (p < 0.01) and the expression of p-eNOS and iNOS were significantly downregulated (p < 0.01). When allicin was administered, expression of p-JNK protein was significantly downregulated. CONCLUSION: Allicin can reduce oxidative stress damage and cardiomyocyte apoptosis in rat model of myocardial infarction and can significantly regulate JNK signaling pathway.

3.
FEMS Microbiol Lett ; 367(7)2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32196075

RESUMO

All well-established cell size homeostasis paradigms are based on the researches of rod bacteria like B. subtilis and E. coli, suggesting a constant division time (timer model), division size (sizer model) or added size (adder model) before division. However, Lysinibacillus varians, a new species with regular filament-to-rod cell cycle, is inconsistent with existing models. In this study, the cell size parameters of the type strain GY32, were investigated by combing multiple microscopy techniques and single-cell approach. Our results showed that the filaments of strain GY32 were unicellular cells with multiple nucleoids. The division time of GY32 cells was variable and their daughter cells produced by asymmetric binary fission had different birth sizes, which were proportional to their elongation rates, resulting in high heterogeneity among the sister cells. Furthermore, the added size from birth to division was significantly shorter than birth size (p < 0.01) and decreased along generations. The results above revealed that the asymmetric division site and varied cell size parameters resulted in filament-to-rod cell cycle of L. varians and cell size homeostasis could be a more complex and dynamic process than previously assumed. These findings would be helpful in elucidating the open questions in cell division and cell size heterogeneity.

4.
Artigo em Inglês | MEDLINE | ID: mdl-32081423

RESUMO

Estrogen Receptor alpha (ERα) affects the morphology of tumors, which is closely related to the biomechanical properties and the cytoskeletal proteins. In recent years, researchers have found that biomechanical properties and cytoskeletal proteins are closely related to the occurrence and development of tumors and that biomechanical properties can be used as markers for tumor development and drug resistance. The relationship between ERα expression status and biomechanical properties, cytoskeletal proteins is not known. In this study, we found that tamoxifen-resistant breast cancer cells (MCF-7/TamR) altered cell morphology and lacked of ERα expression during the process of the Tamoxifen resistance induction. To determine whether this change was influenced by ERα expression, we transiently constructed another ERα depleted model with ERα siRNA (MCF-7/ERα siRNA) and used atomic force microscope (AFM) to detect morphological and biophysical changes. The results indicated that the roughness and Young's modulus of ERα expression depleted cells were significantly increased, accompanied by rearrangement of the cytoskeletal proteins (F-actin, FLNA, α-tubulin) and the cytoskeletal regulatory protein Rho (Rac1, CDC42) decreased. Our results have demonstrated that ERα depletion affects the biomechanical properties of breast cancer cells, which are related to cytoskeletal protein rearrangement and Rho protein decreased.

5.
J Affect Disord ; 266: 447-455, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32056912

RESUMO

BACKGROUND: Previously, we reported that the longest variant of the GABA A receptor γ2 subunit (GABRG2) was associated with suicidal behavior. The present study therefore aimed to determine whether polymorphisms near the alternatively spliced exon of GABRG2 are associated with suicide attempt (SA) and its related traits, and how these variants might interact with reported childhood trauma (CT) in their association with suicidal behavior. METHODS: We examined 5 single nucleotide polymorphisms (SNPs) of GABRG2. Subjects were suicide Attempters (N = 94), non-suicide attempters (N = 168) with MDD or Bipolar depression, and healthy volunteers (N = 100). Data on demographics, depression severity and suicide attempts were collected. Participants also completed a set of instruments assessing CT, and lifetime aggression and impulsivity.. GABRG2 polymorphisms were genotyped using Sanger sequencing. RESULTS: Allele A of rs211034 was a protective factor for SA (OR = 0.50 (0.32, 0.80), p = 0.003), and had an interaction effect with emotional neglect (OR = 0.89 (0.82, 0.97), p = 0.006) on depression. One haploblock (consisting of rs211035 and rs211034) was identified within these SNPs, and subjects with haplotype GA (frequency = 7.3%), had lower rate of SA (OR=0.26(0.10, 0.67), p = 0.006). Cognitive impulsivity (OR=1.38)1.24,1.55), p < 0.001), non-planning impulsivity (OR = 1.18 (1.10,1.25), p < 0.001), anger (OR = 1.13 (1.07,1.19), p < 0.001), impulsivity total score (OR = 1.10(1.06,1.15), p < 0.001), hostility (OR = 1.10 (1.04, 1.15), p < 0.001), aggression total score (OR = 1.05 (1.03,1.07), p < 0.001) were associated with depression, meanwhile, hopelessness (OR = 2.18 (1.56, 3.04), p < 0.001) and impulsivity total score (OR = 1.05 (1.02,1.08), p < 0.001) were associated with the risk of SA, adjusted by age and gender. There was no mediation effect in the relationship among CT, gene polymorphisms and SA or depression through increased impulsivity or aggression. LIMITATIONS: The main limitation of this study is its modest sample size. More genetic variants as well as epigenetic markers should be examined in future studies. CONCLUSIONS: These findings add to evidence for the involvement of GABRG2 and impulsivity and hopelessness in SA independent from their association with depression. More research is needed on possible mediators of the relationship between GABA-related gene and SA.

6.
J Hazard Mater ; 388: 122068, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-31955029

RESUMO

Nitrate and sulfate are electron acceptors (EAs) for biodegradation of polycyclic aromatic hydrocarbons (PAHs) in anaerobic sediments. The efficiency of PAHs biodegradation depends on the strength of the interactions between PAH-degradation and EA-reduction assemblages. However, these interactions are less studied. In this study, microbial response and PAH degradation efficiencies in river sediment were investigated using nitrate and sulfate stimulation. Results showed that the functional assemblages (PAH-degraders, nitrate- and sulfate- reducers) were low connectivity in the microbial network without EA adding. Nitrate input rapidly (<1 day) raised the nitrate reduction intensity. And the PAH-degraders and nitrate reducers established significant and direct correlations under nitrate stimulation, seen from the 13 connectors (nodes) in the microbial network. In contrast, sulfate reducers slowly increased in abundance (>20 days) and were connected to PAH-degraders through indirect connection under sulfate stimulation. The null model suggested that nitrate led to a higher level of directional selection, which implied that nitrate was a more favorable EA to trigger the deterministic succession. As a result, PAHs degradation was faster with nitrate stimulation (t1/2 = 68.3 d) than with sulfate stimulation (t1/2 = 164.6 d). These mechanistic understandings can serve as the guidelines for EA selection in bioremediation.

7.
Biosens Bioelectron ; 148: 111832, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31706173

RESUMO

Fluorescence-activated cell sorting (FACS) has rarely been applied to screening of microorganisms because of poor detection resolution, which is compromised by poor stability, toxicity, or interference from background fluorescence of the fluorescence sensors used. Here, a fluorescence-based rapid high-throughput cell sorting method was first developed using a fluorescence resonance energy transfer (FRET) fluorescent nanoprobe NP-RA, which was constructed by coating a silica nanoparticle with Rhodamine B and methyl-red (an azo dye). Rhodamine B (inner layer) is the FRET donor and methyl-red (outer layer) is the acceptor. This ready-to-use NP-RA is non-fluorescent, but fluoresces once the outer layer is degraded by microorganisms. In our experiment, NP-RA was ultrasensitive to model strain Shewanella decolorationis S12, showing a broad detection range from 8.0 cfu/mL to 8.7 × 108 cfu/mL under confocal laser scanning microscopy, and from 1.1 × 107 to 9.36 × 108 cfu/mL under a fluorometer. In addition, NP-RA bioimaging can clearly identify other azo-respiring cells in the microbial community, including Bosea thiooxidans DSM 9653 and Lysinibacillus pakistanensis NCCP-54. Furthermore, the fluorescent probe NP-RA is compatible with downstream FACS so that azo-respiring cells can be rapidly sorted out directly from an artificial microbial community. To our knowledge, no fluorescent nanoprobe has yet been designed for tracking and sorting azo-respiration functional microorganisms.


Assuntos
Compostos Azo/química , Transferência Ressonante de Energia de Fluorescência/métodos , Corantes Fluorescentes/química , Rodaminas/química , Shewanella/isolamento & purificação , Bacillaceae/isolamento & purificação , Técnicas Biossensoriais/métodos , Bradyrhizobiaceae/isolamento & purificação , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Nanopartículas/química , Dióxido de Silício/química
8.
Opt Express ; 27(22): 32733-32745, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31684480

RESUMO

Fast source optimization (SO) is in demand urgently for holistic lithography on-line at 14-5 nm nodes. Our earlier works of fast compressive sensing (CS) SO methods adopted randomly sampling monitoring pixels on layout patterns, consequently resulting in failure of SO sometimes and poor image fidelity compared to gradient-based SO with complete sampling (SD-SO). This paper proposes a novel certain contour sampling-Bayesian compressive sensing SO (CCS-BCS-SO) method to achieve the goals of fast SO and high fidelity patterns simultaneously. The CCS assures the optimized source uniquely and reduces the computational complexity significantly. The BCS theory, to our best knowledge, is for the first time applied to resolution enhancement techniques (RETs) in lithography systems to ensure high fidelity patterns. The results demonstrate that CCS-BCS-SO simultaneously achieves fast SO like CS-SO and high fidelity patterns like SD-SO.

9.
Mol Med ; 25(1): 51, 2019 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-31747876

RESUMO

BACKGROUND: This study aimed to investigate the differences in the serum levels of glucose, lipid, and thyroid function markers between unipolar and bipolar depressed patients, as well as the effect of anhedonia and suicidal thoughts on the levels of these biochemical parameters. METHODS: A total of 287 unmedicated depressed patients from January 2016 to December 2017 were included in this study, including 92 bipolar depressions and 195 unipolar depressions. Anhedonia was determined using the item 32 of Symptom Checklist (SCL-90). Suicide ideation was assessed by item 15 of SCL-90. RESULTS: The bipolar group had significantly lower lipid levels (including triglycerides, cholesterol, low-density lipoprotein cholesterol [LDL], very low-density lipoprotein cholesterol [VLDL]) and insulin resistance index but higher levels of prolactin, low triiodothyronine (T3) and free T3 (FT3) as well as higher incidence of anhedonia as compared with the unipolar group. Depressed patients with anhedonia had significantly higher LDL level than those without anhedonia. Depressed patients with suicidal thoughts had cholesterol and high-density lipoprotein cholesterol (HDL) level. The above-mentioned differences were confirmed by logistic regression analysis. Receiver operating characteristic curve (ROC) analysis showed that the area under the ROC curve (AUC) ranged from 0.546 to 0.685. CONCLUSION: Triglycerides, cholesterol, LDL, VLDL T3, FT3 levels were significantly different between unipolar and bipolar depressed patients, which might have the potential to be the markers for differential diagnosis. Patients with anhedonia had lower LDL level, while patients with suicidal thoughts had higher levels of cholesterol and HDL as compared with the corresponding control groups.


Assuntos
Anedonia , Transtorno Bipolar , Depressão , Lipídeos/sangue , Ideação Suicida , Hormônios Tireóideos/sangue , Adulto , Transtorno Bipolar/sangue , Transtorno Bipolar/epidemiologia , Transtorno Bipolar/psicologia , Depressão/sangue , Depressão/epidemiologia , Depressão/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
10.
Appl Opt ; 58(30): 8331-8338, 2019 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-31674509

RESUMO

Some pupil wavefront optimization (PWO) approaches were studied to compensate the thick mask effects considering only a field point, and these PWO methods neglect the inherent wave aberration in a realistic lithography system. Particularly, the wave aberration of lithography projection optics is exposure field dependent, and the wave aberrations at different fields of view (FOVs) would seriously and unevenly impact the results and effects of PWO. The current PWO method for single FOV cannot match full FOV. In this paper, we propose a multiple-field-point PWO (MPWO) method to improve lithography imaging quality for full FOV. A multiple-field-point cost function is built including the uneven impact of multiple aberrations on lithography imaging at full FOV. The comprehensive simulations demonstrate that the proposed MPWO method can effectively improve consistency of lithography imaging and enlarge the overlapped process window for full FOV. The most important point is that the optimized wavefront attained by MPWO can be realized via pupil wavefront manipulator FlexWave in lithography equipment, which is significant in holistic lithography for the next technology node.

11.
Int J Mol Sci ; 20(20)2019 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-31614702

RESUMO

Bacillus velezensis FZB42 is able to activate induced systemic resistance (ISR) to enhance plant defense response against pathogen infections. Though the roles of microRNAs (miRNAs) in Bacillus-triggered ISR have been reported in Arabidopsis, the maize miRNAs responsible for the Bacillus-activated ISR process have not been discovered. To explore the maize miRNAs involved in ISR, maize miRNAs in response to FZB42 (ISR activating), FZB42△sfp△alss (deficient in triggering ISR), and a control for 12 h were sequenced. A total of 146 known miRNAs belonging to 30 miRNA families and 217 novel miRNAs were identified. Four miRNAs specifically repressed in FZB42-treatment were selected as candidate ISR-associated miRNAs. All of them contained at least one defense response-related cis-element, suggesting their potential roles in activating the ISR process. Interestingly, three of the four candidate ISR-associated miRNAs belong to the conserved miR169 family, which has previously been confirmed to play roles in abiotic stress response. Moreover, 52 mRNAs were predicted as potential targets of these candidate ISR-associated miRNAs through TargetFinder software and degradome sequencing. Gene Ontology (GO) and network analyses of target genes showed that these differentially expressed miRNA might participate in the ISR process by regulating nuclear factor Y transcription factor. This study is helpful in better understanding the regulatory roles of maize miRNAs in the Bacillus-activated ISR process.


Assuntos
Resistência à Doença , MicroRNAs/genética , Zea mays/genética , Bacillus/patogenicidade , MicroRNAs/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Zea mays/imunologia , Zea mays/microbiologia
12.
Front Microbiol ; 10: 1623, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31379778

RESUMO

Flavin mononucleotide (FMN) and riboflavin are structurally similar flavins, except for the presence of a phosphate group on the FMN molecule. They are used by a variety of electroactive bacteria as extracellular electron shuttles in microbial Fe reduction and inevitably interact with Fe (hydr)oxides in the extracellular environment. It is currently unknown whether flavin/Fe (hydr)oxide interaction interferes with extracellular electron transfer (EET) to the mineral surface. In this study, we found that the goethite reduction rate was lower when mediated by FMN than by RF, suggesting that FMN was less effective in shuttling electrons between cells and minerals. Nevertheless, the phosphate group did not prevent the FMN molecule from accepting electrons from bacterial cells and transferring electrons to the mineral. Results of adsorption experiment, attenuated total reflectance (ATR) Fourier transform infrared (FTIR) spectroscopy, and bacterial attachment trend analyses showed that FMN exhibited strong adsorption on goethite surface by forming phosphate inner-sphere complex, which prevented bacterial cells from approaching goethite. Therefore, the interaction between FMN and goethite surface may increase the distance of electron transfer from bacterial cells to goethite and result in lower EET efficiency in comparison to those mediated by riboflavin. To our knowledge, these data reveal for the first time that the interaction between flavin and Fe (hydr)oxide affect flavin-mediated electron transfer to mineral surface and add a new dimension to our understanding of flavin-mediated microbial Fe reduction processes.

13.
BMC Biotechnol ; 19(1): 52, 2019 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-31345193

RESUMO

BACKGROUND: Packing materials is a critical design consideration when employing biological reactor to treat malodorous gases. The acidification of packing bed usually results in a significant drop in the removal efficiency. In the present study, a biotrickling filter (BTF2) packed with plastic balls in the upper layer and with lava rocks in the bottom layer, was proposed to mitigate the acidification. RESULTS: Results showed that using combined packing materials efficiently enhanced the removal performance of BTF2 when compared with BTF1, which was packed with sole lava rocks. Removal efficiencies of more than 92.5% on four sulfur compounds were achieved in BTF2. Average pH value in its bottom packing bed was about 4.86, significantly higher than that in BTF1 (2.85). Sulfate and elemental sulfur were observed to accumulate more in BTF1 than in BTF2. Analysis of principal coordinate analysis proved that structure of microbial communities in BTF2 changed less after the shutdown but more when the initial pH value was set at 5.5. Network analysis of significant co-occurrence patterns based on the correlations between microbial taxa revealed that BTF2 harbored more diverse microorganisms involving in the bio-oxidation of sulfur compounds and had more complex interactions between microbial species. CONCLUSIONS: Results confirmed that using combined packing materials effectively improved conditions for the growth of microorganisms. The robustness of reactor against acidification, adverse temperature and gas supply shutdown was greatly enhanced. These provided a theoretical basis for using mixed packing materials to improve removal performance.


Assuntos
Filtros de Ar/microbiologia , Reatores Biológicos/microbiologia , Microbiota , Compostos de Enxofre/isolamento & purificação , Compostos de Enxofre/metabolismo , Poluentes Atmosféricos/isolamento & purificação , Poluentes Atmosféricos/metabolismo , Biodegradação Ambiental , Filtração/instrumentação , Filtração/métodos , Oxirredução
14.
Front Microbiol ; 10: 1452, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31293561

RESUMO

Iron (hydr)oxides are the most ubiquitous Fe(III)-containing minerals in the near-surface environments and can regulate organic pollutant biotransformation by participating in bacterial extracellular electron transfer under anaerobic conditions. Mechanisms described so far are based on their redox properties in bacterial extracellular respiration. Here, we find that goethite, a typical iron (hydr)oxide, inhibits the bioreduction of different polar azo dyes by Shewanella decolorationis S12 not through electron competition, but by the contact of its surface Fe(III) with the bacterial outer surface. Through the combined results of attenuated total reflectance (ATR) Fourier transform infrared spectroscopy, two-dimensional correlation spectroscopy, and confocal laser scanning microscope, we found that the outer membrane proteins MtrC and OmcA of strain S12 are key binding sites for goethite surface. Meanwhile, they were identified as the important reductive terminals for azo dyes. These results suggest that goethite may block the terminal reductive sites of azo dyes on the bacterial outer membrane to inhibit their bioreduction. This discovered role of goethite in bioreduction provides new insight into the microbial transformation processes of organic pollutants in iron (hydr)oxide-containing environments.

15.
Appl Opt ; 58(14): 3718-3728, 2019 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-31158182

RESUMO

Extreme ultraviolet lithography is regarded as the most attractive technology to achieve 7 nm node and below. A new high-numerical-aperture anamorphic objective lens is designed to extend the single exposure resolution limit. However, the polarization aberrations (PAs) induced by the multilayer coatings on mirrors cause pattern distortions that cannot be neglected. In this paper, a source, mask, and process parameter co-optimization method is developed to compensate for the pattern distortions caused by PAs and increase the process window (PW). We first present an asymmetric source represented by the superposition of Zernike polynomials to reduce the pattern placement error (PPE). Then, a weighted cost function that incorporates the influences of PAs is innovated. Finally, a gradient-based statistical optimization method is adopted to minimize the cost function by optimizing the lithography system parameters alternately. Simulations at the 7 nm node of the 1D mask pattern indicate that for the system with a PA of marginal field, compared with our earlier work, the critical dimension error and PPE of the proposed method are reduced by 75.0% and 82.4%, respectively, and the PW is increased by 97.4%.

16.
Appl Environ Microbiol ; 85(16)2019 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-31175185

RESUMO

Bacterial anaerobic respiration using an extracellular electron acceptor plays a predominant role in global biogeochemical cycles. However, the mechanisms of bacterial adaptation to the toxic organic pollutant as the extracellular electron acceptor during anaerobic respiration are not clear, which limits our ability to optimize the strategies for the bioremediation of a contaminated environment. Here, we report the physiological characteristics and the global gene expression of an ecologically successful bacterium, Shewanella decolorationis S12, when using a typical toxic organic pollutant, amaranth, as the extracellular electron acceptor. Our results revealed that filamentous shift (the cells stretched to fiber-like shapes as long as 18 µm) occurred under amaranth stress. Persistent stress led to a higher filamentous cell rate and decolorization ability in subcultural cells compared to parental strains. In addition, the expression of genes involved in cell division, the chemotaxis system, energy conservation, damage repair, and material transport in filamentous cells was significantly stimulated. The detailed roles of some genes with significantly elevated expressions in filamentous cells, such as the outer membrane porin genes ompA and ompW, the cytochrome c genes arpC and arpD, the global regulatory factor gene rpoS, and the methyl-accepting chemotaxis proteins genes SHD_2793 and SHD_0015, were identified by site-directed mutagenesis. Finally, a conceptual model was proposed to help deepen our insights into both the bacterial survival strategy when toxic organics were present and the mechanisms by which these toxic organics were biodegraded as the extracellular electron acceptors.IMPORTANCE Keeping toxic organic pollutants (TOPs) in tolerable levels is a huge challenge for bacteria in extremely unfavorable environments since TOPs could serve as energy substitutes but also as survival stresses when they are beyond some thresholds. This study focused on the underlying adaptive mechanisms of ecologically successful bacterium Shewanella decolorationis S12 when exposed to amaranth, a typical toxic organic pollutant, as the extracellular electron acceptor. Our results suggest that filamentous shift is a flexible and valid way to solve the dilemma between the energy resource and toxic stress. Filamentous cells regulate gene expression to enhance their degradation and detoxification capabilities, resulting in a strong viability. These novel adaptive responses to TOPs are believed to be an evolutionary achievement to succeed in harsh habitats and thus have great potential to be applied to environment engineering or synthetic biology if we could picture every unknown node in this pathway.


Assuntos
Compostos Azo/metabolismo , Corantes/metabolismo , Shewanella/metabolismo , Anaerobiose , Compostos Azo/toxicidade , Proteínas de Bactérias/genética , Biodegradação Ambiental , Corantes/toxicidade , Transporte de Elétrons , Elétrons , Oxirredução , Shewanella/efeitos dos fármacos , Shewanella/genética
17.
Opt Express ; 27(11): 15604-15616, 2019 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-31163755

RESUMO

Source and mask optimization (SMO) technology based on vectorial image model is indispensable in immersion lithography process at advanced technology node. Many kinds of algorithms have achieved successes in aspect of fast and robust SMO without accounting polarization aberration (PA). However, because the PA arising from immersion projection optics unevenly impacts on imaging performance, the conventional SMO would not be applicable in real lithography system. In this paper, we first investigate the serious impact of PA on SMO in details. The SMO accounting the assigned PA of one field point is not applicable to other field points, where the pattern fidelity is fiercely worse and the pattern error (PAE) is nearly doubled. Then, we innovate a MOSMO method to reduce the uneven impact of PA on lithography imaging at full exposure field. Compared to the assigned PA aware SMO, the proposed MOSMO reduces the standard deviation of PAE distribution by 53.3% and enlarges the maximum exposure latitude from 4% to 6.7%, which demonstrates the MOSMO is very significant to balance imaging quality and improve process robustness at full exposure field.

18.
Opt Express ; 27(3): 2754-2770, 2019 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-30732308

RESUMO

Source and mask optimization (SMO) is an important method to improve lithography imaging fidelity. However, constrained by the computational inefficiency, the current SMO method can be used only in clip level applications. In this paper, to our best knowledge, the fast nonlinear compressive sensing (CS) theory is for the first time applied to solve the nonlinear inverse reconstruction problem in SMO. The proposed method simultaneously downsamples the layout pattern in the SMO procedure, which can effectively reduce the computation complexity. The space basis and two-dimensional (2D) discrete cosine transform (DCT) basis are selected to sparsely represent the source pattern and mask pattern, respectively. Based on the sparsity assumption of source and mask pattern, the SMO can be formulated as a nonlinear CS reconstruction problem. A Newton-iteration hard thresholding (Newton-IHTs) algorithm, by taking into account the second derivative of the cost function to accelerate convergence, is innovated to realize nonlinear CS-SMO with high imaging fidelity. Simulation results show the proposed method can significantly accelerate the SMO procedure over a traditional gradient-based method and IHTs-based method by a factor of 9.31 and 7.39, respectively.

19.
Pharmacology ; 103(3-4): 136-142, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30602153

RESUMO

To investigate the effect of Tanshinone IIA (TSA) on viral myocarditis (VMC). VMC animal model was established using BALB/c mice by intraperitoneally injecting Coxsackie virus B3 (CVB3). The mice were randomly divided into control group, model group, and TSA group. We detected the survival rate, the heart weight to body weight (HW/BW) ratio and hemodynamic and cardiac function parameters. The pathological features of VMC were measured through H&E staining. The expression of serum enzyme, inflammatory cytokines, and T helper (Th)1/Th2 markers was also investigated. TSA remarkably alleviated CVB3-caused myocardial injury, decreased the HW/BW ratio, and improved survival rate. TSA obviously improved hemodynamic parameters and reversed the damage to the heart pump function. Furthermore, the serum levels of lactate dehydrogenase, creatine kinase, and Th1 cytokines in the TSA group were significantly lower than those in the VMC group, and TSA treatment significantly improved the pathological condition. The interferon-gamma (IFN-γ) and interleukin-2 (IL-2) levels in VMC model group was higher than control group, and lower levels of IL-4 and IL-10 were identified. However, TSA treatment elevated IL-4 and IL-10 levels and decreased IFN-γ and IL-2 levels. TSA could effectively protect the myocardium against CVB3-induced myocarditis by the inhibition of inflammation and modulation Th1/Th2 balance in mice.


Assuntos
Abietanos/farmacologia , Anti-Inflamatórios/farmacologia , Infecções por Coxsackievirus/prevenção & controle , Enterovirus/patogenicidade , Miocardite/prevenção & controle , Miocárdio , Células Th1/efeitos dos fármacos , Células Th2/efeitos dos fármacos , Animais , Infecções por Coxsackievirus/sangue , Infecções por Coxsackievirus/imunologia , Infecções por Coxsackievirus/virologia , Citocinas/sangue , Modelos Animais de Doenças , Enterovirus/imunologia , Mediadores da Inflamação/sangue , Masculino , Camundongos Endogâmicos BALB C , Miocardite/sangue , Miocardite/imunologia , Miocardite/virologia , Miocárdio/imunologia , Miocárdio/metabolismo , Miocárdio/patologia , Células Th1/imunologia , Células Th1/metabolismo , Células Th1/virologia , Equilíbrio Th1-Th2/efeitos dos fármacos , Células Th2/imunologia , Células Th2/metabolismo , Células Th2/virologia
20.
Int J Biochem Cell Biol ; 113: 104-114, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30660690

RESUMO

Sonodynamic therapy (SDT) is a noninvasive therapeutic method via the activation of certain chemical sensitizers using low intensity ultrasound. In this work, we evaluated the antitumor effect of sinoporphyrin sodium (DVDMS) mediated SDT (DVDMS-SDT) on Hepatocellular carcinoma (HCC) cell lines both in vitro and in vivo. The results indicated that DVDMS-SDT was significantly more efficacious than PpIX-SDT in treating hepatocellular cell line Hep-G2. DVDMS-SDT also increased the ratio of cells in the G2/M phase and decreased the CDK1 and Cyclin B1 protein level. DVDMS-SDT markedly increased intracellular reactive oxygen species (ROS) in vitro. The increased ROS production up-regulated the expression of p53 and Bax, and down-regulated Bcl-2 expression, which led to the activation of caspase-3, ultimately initiated cell apoptosis. These effects could be partially reversed by the ROS scavenger N-acetylcysteine (NAC). In vivo experiments revealed that the DVDMS-SDT resulted in an effective inhibition of tumor growth and prolonged the survival time of tumor-bearing mice. More importantly, no obvious signs of side effects were observed. These results suggested that DVDMS-SDT is very effective in treating Hepatocellular carcinoma without side effects. The primary mechanism of SDT is due to the increased ROS activated the p53/Caspase 3 axis of apoptosis.


Assuntos
Carcinoma Hepatocelular/terapia , Caspase 3/metabolismo , Neoplasias Hepáticas/terapia , Porfirinas/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Terapia por Ultrassom , Animais , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Feminino , Células Hep G2 , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Espécies Reativas de Oxigênio/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
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