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1.
Food Res Int ; 163: 112309, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36596207

RESUMO

Increasing evidence has suggested the mitigatory efficacy of prebiotic inulin on nonalcoholic fatty liver disease (NAFLD), nevertheless, its action mechanisms remain elusive. Herein, inulin consumption effectively ameliorated high-sucrose diet-induced hepatic steatosis and inflammation, and rehabilitated liver lipogenesis regulators, including carbohydrate response element-binding protein, stearoyl-CoA desaturase-1 and peroxisome proliferator-activated receptor alpha. Furthermore, inulin supplementation restored the intestinal barrier integrity and function by up-regulating expressions of tight junction proteins (zonula occludens-1, claudin-1 and occludin). High-throughput sequencing demonstrated that inulin administration regulated the gut microbiota composition, wherein abundance of short-chain fatty acid (SCFA)-producers, including Bifidobacterium, Phascolarctobacterium and Blautia, was significantly enhanced in the inulin-treated rats, conversely, opportunistic pathogens, such as Acinetobacter and Corynebacterium_1, were suppressed. SCFA quantitative analysis showed that dietary inulin suppressed faecal acetate levels, but improved propionate and butyrate concentrations in rats with NAFLD. Functional prediction showed that tryptophan metabolism was one of the key metabolic pathways affected by gut microbiota changes. A targeted metabolomics profiling of tryptophan metabolism demonstrated that inulin intervention up-regulated faecal contents of indole-3-acetic acid and kynurenic acid, whereas down-regulated levels of kynurenine and 5-hydoxyindoleacetic acid in NAFLD rats. Therefore, this study demonstrated that inulin intake alleviated hepatic steatosis likely by regulating the gut microbiota composition and function and restoring the intestinal barrier integrity, which may provide a novel notion for the prevention and treatment of NAFLD in future.


Assuntos
Microbioma Gastrointestinal , Hepatopatia Gordurosa não Alcoólica , Ratos , Animais , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Inulina/farmacologia , Triptofano , Ácidos Graxos Voláteis
2.
Sensors (Basel) ; 23(1)2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36617068

RESUMO

Radio signals are polluted by noise in the process of channel transmission, which will lead to signal distortion. Noise reduction of radio signals is an effective means to eliminate the impact of noise. Using deep learning (DL) to denoise signals can reduce the dependence on artificial domain knowledge, while traditional signal-processing-based denoising methods often require knowledge of the artificial domain. Aiming at the problem of noise reduction of radio communication signals, a radio communication signal denoising method based on the relativistic average generative adversarial networks (RaGAN) is proposed in this paper. This method combines the bidirectional long short-term memory (Bi-LSTM) model, which is good at processing time-series data with RaGAN, and uses the weighted loss function to construct a noise reduction model suitable for radio communication signals, which realizes the end-to-end denoising of radio signals. The experimental results show that, compared with the existing methods, the proposed algorithm has significantly improved the noise reduction effect. In the case of a low signal-to-noise ratio (SNR), the signal modulation recognition accuracy is improved by about 10% after noise reduction.

3.
Artigo em Inglês | MEDLINE | ID: mdl-36674067

RESUMO

The removal of heavy metals is crucial to the utilization of contaminated biomass resources. In this study, we report an efficient process of hydrothermal conversion (HTC) of sunflower straw (Helianthus annuus L.) to remove heavy metals. The effect of different HTC temperatures and concentrations of HCl additives on heavy metal removal efficiency was investigated. The results revealed that increasing the temperature or concentration of HCl promoted the transfer of heavy metals from hydrochar to liquid products during HTC. The heavy metals removed to the liquid products included up to 99% of Zn and Cd, 94% of Cu, and 87% of Pb after hydrothermal conversion with a temperature of 200 °C and HCl 2%. The species of heavy metals in hydrochars converted from unstable to stable with an increase in temperature from 160 °C to 280 °C. The stable fractions of heavy metals in the acidic condition decreased as the acid concentration increased. This aligns well with the high transfer efficiency of heavy metals from the solid phase to the liquid phase under acidic conditions. The FTIR indicated that the carboxy and hydroxy groups decreased significantly as the temperature increased and the concentration of HCl increased, which promoted the degradation of sunflower straw. A scan electron microscope showed that the deepening of the destruction of the initial microstructure promotes the transfer of heavy metals from hydrochars to liquid phase products. This acid-assisted hydrothermal process is an efficient method to treat biomass containing heavy metals.


Assuntos
Helianthus , Metais Pesados , Helianthus/metabolismo , Metais Pesados/química , Temperatura
4.
Gastroenterol Rep (Oxf) ; 11: goac084, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36632622

RESUMO

Background: The histologically complete resection (CR) rate of small rectal neuroendocrine tumors (RNETs) is unsatisfactory at the first endoscopy. Risk factors and clinical outcomes associated with incomplete resection (IR) have not been explicitly elucidated. This study aims to explore the relevant factors of IR. Methods: This retrospective study reviewed patients with small RNETs (≤10 mm) in eight centers from January 2013 to December 2021. Clinicopathological characteristics and clinical outcomes were compared between the CR and IR groups, and the polypectomy and advanced treatment groups. Results: Of the 326 patients included, 83 (25.5%) were diagnosed with IR. Polypectomy (odds ratio [OR] = 16.86), a central depression (OR = 7.50), and treatment in the early period (OR = 2.60) were closely associated with IR. Further analysis revealed that an atypical hyperemic appearance (OR = 7.49) and treatment in the early period (OR = 2.54) were significantly associated with the inappropriate use of polypectomy (both P < 0.05). In addition, a total of 265 (81.3%) were followed up with a median follow-up period of 30.9 months. No death, metastasis, or recurrence was found during the follow-up period. Conclusions: Polypectomy, a central depression, and treatment in the early period were risk factors for IR. Further, an atypical hyperemic appearance and treatment in the early period were significant predisposing factors for inappropriate choice of polypectomy. For histologically incompletely resected small RNETs, follow-up may be a safe and feasible alternative to rigorous salvage therapy.

6.
Int J Mol Sci ; 23(24)2022 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-36555743

RESUMO

Xyloglucan endotransglycosylase/hydrolase (XTH) genes play an important role in plant resistance to abiotic stress. However, systematic studies of the response of Boehmeria nivea (ramie) XTH genes (BnXTHs) to cadmium (Cd) stress are lacking. We sought to identify the BnXTH-family genes in ramie through bioinformatics analyses and to investigate their responses to Cd stress. We identified 19 members of the BnXTH gene family from the ramie genome, referred to as BnXTH1-19, among which BnXTH18 and BnXTH19 were located on no chromosomes and the remaining genes were unevenly distributed across 11 chromosomes. The 19 members were divided into four groups, Groups I/II/IIIA/IIIB, according to their phylogenetic relationships, and these groups were supported by analyses of intron-exon structure and conserved motif composition. A highly conserved catalytic site (HDEIDFEFLG) was observed in all BnXTH proteins. Additionally, three gene pairs (BnXTH6-BnXTH16, BnXTH8-BnXTH9, and BnXTH17-BnXTH18) were obtained with a fragment and tandem-repeat event analysis of the ramie genome. An analysis of cisregulatory elements revealed that BnXTH expression might be regulated by multiple hormones and abiotic and biotic stress responses. In particular, 17 cisregulatory elements related to abiotic and biotic stress responses and 11 cisregulatory elements related to hormone responses were identified. We also found that most BnXTH genes responded to Cd stress, and BnXTH1, BnXTH3, BnXTH6, and BnXTH15 were most likely to contribute to the Cd tolerance of ramie, as evidenced by the substantial increases in expression under Cd treatment. Heterologous expression of BnXTH1, BnXTH6, and BnXTH15 significantly enhanced the Cd tolerance of transgenic yeast cells. These results suggest that the BnXTH gene family is involved in Cd stress responses, laying a theoretical foundation for functional studies of BnXTH genes and the innovative breeding of Cd-tolerant ramie.


Assuntos
Boehmeria , Cádmio , Cádmio/toxicidade , Cádmio/metabolismo , Boehmeria/genética , Boehmeria/metabolismo , Filogenia , Melhoramento Vegetal , Regulação da Expressão Gênica de Plantas
7.
Front Microbiol ; 13: 1080484, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36532504

RESUMO

Acute-on-chronic liver failure (ACLF) is a major cause of liver-related death worldwide, but its key pathological features remain incompletely defined. This study aimed to reveal the molecular basis of hepatitis B virus-related ACLF (HBV-ACLF) by transcriptome sequencing of human liver tissue. A total of 18 human liver tissues from patients with different stages of HBV-related disease were collected for RNA sequencing, and liver tissues from patients and mouse models with ACLF were used for subsequent validation. Specifically, 6,853 differentially expressed genes (DEGs) and 5,038 differentially expressed transcripts were identified in patients with ACLF compared to patients with chronic hepatitis B (CHB) and normal controls (NCs). Investigation of functional by KEGG pathway enrichment analysis revealed prominent immune and metabolic dysregulation at the ACLF stage. We found that the key genes FGF19, ADCY8 and KRT17, which are related to immunometabolic disturbances, were significantly upregulated in the progression of ACLF. The three key genes were validated in human and mouse samples, indicating their prognostic and therapeutic potential in ACLF. In summary, our work reveals that immunometabolic disorder is involved in HBV-ACLF pathogenesis and indicates that FGF19, ADCY8 and KRT17 may be sensitive biomarkers for HBV-related ACLF.

8.
Nat Protoc ; 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36517608

RESUMO

The large pores of functional mesoporous carbonaceous nanomaterials have broad accessibility, making them efficient substrates for the mass transport of chemicals in biomedical applications, gas separation, catalysis, sensing, and energy storage and conversion. Recently, the assembly of monomicelles has been used to control the nanostructure and mesoporosity of carbonaceous nanomaterials, where the structure-oriented unit is a single micelle made up of block copolymers/surfactants and of precursor species (via hydrogen bonds, Coulombic and/or other noncovalent interactions). Each monomicelle then represents a template for a single mesopore, and multiple monomicelles can be stacked like LEGO blocks. After polymerization of the precursor species (in this case dopamine), carbonization results in the carbonaceous nanomaterial. The micellar size, structure and shape can be easily tuned by altering the synthetic conditions, providing a high degree of control over the structure of the final product, which can therefore be shaped into original nanostructures otherwise difficult to synthesize using conventional templating methods. Here we provide a detailed procedure for the preparation of the monomicelles, the monomicellar assembly into mesostructured polymeric samples and the conversion of polymeric samples to carbonaceous frameworks. We describe the functional characterization of two mesoporous carbonaceous nanomaterials that demonstrate excellent sodium-ion storage performance and oxygen reduction reactivity, respectively. The monomicellar assembly process for the synthesis of the ordered mesoporous polymers requires ~5 h; the synthesis, including subsequent centrifugation, freeze drying and carbonization, requires 2 d, whereas the entire procedure, including the characterization of the nanomaterials, requires ~4 d.

9.
Can J Gastroenterol Hepatol ; 2022: 7499492, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36439633

RESUMO

Background: Chronic hepatitis B (CHB) patients with normal or minimally increased levels of alanine aminotransferase (ALT) are still at the risk of hepatocellular carcinoma, cirrhotic events, and mortality. However, there is a debate over the initiation of antiviral treatment for these patients. This systematic review and mate-analysis aimed to explore this problem. Methods: MEDLINE (PubMed), EMBASE, Cochrane Central Register of Controlled Trials, and Web of Science databases were systematically searched for retrieving relevant studies with risk ratios (RRs) or risk differences (RDs) for virological changes between antivirus-treated and no antivirus-treated CHB patients with ALT levels less than two-fold of the upper limit of normal. Retrieved data ranged from January 1990 to October 2020. Results: Of 6783 abstracts screened, 9 studies met the criteria for inclusion in the systematic review and had a low risk of bias. Among studies that were involved in the meta-analyses, it was found that the rates of HBsAg loss (RR = 12.22, 95% confidence interval (CI): 4.28-34.95, P < 0.001), HBsAg seroconversion (RR = 19.90, 95% CI: 2.75-144.09, P=0.003), and undetectable HBV DNA (RR = 11.89, 95% CI: 2.44-57.89, P=0.002) were both higher in the antiviral treatment group compared with placebo or no treatment group. Subgroup analysis suggested that patients who received interferon (IFN)-based therapy were more inclined to achieve HBsAg loss (P=0.010), HBsAg seroconversion (P=0.020), and HBeAg loss (P=0.002). Conclusion: From a sizable population, it was revealed that CHB patients with normal or minimally increased levels of ALT could benefit from the antiviral therapy, especially those who received IFN-based treatment.


Assuntos
Hepatite B Crônica , Neoplasias Hepáticas , Humanos , Alanina Transaminase , Hepatite B Crônica/tratamento farmacológico , Antígenos de Superfície da Hepatite B , Antivirais/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico
10.
Chin Herb Med ; 14(4): 592-601, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36405058

RESUMO

Objective: Spaceflight has long been perceived as an effective way to improve the quantity and quality of plants with wide applications. In order to obtain stable and inheritable descendants of spaceflight-induced Salvia miltiorrhiza lines, we investigated and analyzed four lines m16, m50, m51, m57 (three individuals of each line) and the ground control (three individuals) of the third generation of spaceflight-induced S. miltiorrhiza from primary/secondary metabolism and antioxidative abilities. Methods: A portable photosynthesis system (Li-6400) with red/blue LED light source was used to perform the photosynthetic characteristics to evaluate their primary productivity. The secondary metabolites (phenolic acids, tanshinones, total phenolics and flavonoids) and antioxidant activity of roots were analyzed to assess their quality. Results: Compared with control, line m16 presented weak photosynthetic ability, but high apparent quantum yield (AQY), higher contents of secondary metabolites, and stronger antioxidative abilities. Line m57 had a strong gas exchange ability, relatively higher secondary metabolites contents, and ascending antioxidative abilities. Lines m50 and m51 were in the middle level of lines m16 and m57. The principal component analysis for all the original data revealed three components including a root-related index, a leaf-related index, and a CO2 response parameter could be used to distinguish spaceflight-induced S. miltiorrhiza lines. Conclusion: Line m57 could be an appropriate material for the investigation of targeted breeding towards high production, and line m16 could be used to identify essential genes and unravel sophisticated pathways underlying the secondary metabolisms.

11.
J Hematol Oncol ; 15(1): 167, 2022 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-36384978

RESUMO

A novel recombinant SIRPα-Fc fusion protein, IMM01, was constructed and produced using an in-house developed CHO-K1 cell expression system, and the anti-tumor mechanism of IMM01 targeting the CD47-SIRPα pathway was explored. The phagocytosis and in vitro anti-tumor activity of IMM01 were evaluated by antibody-dependent cellular phagocytosis (ADCP), antibody-dependent cell-mediated cytotoxicity (ADCC), and complement-dependent cytotoxicity (CDC) assays. In vivo mouse tumor model studies were used to explore therapeutic efficacy as well as the mechanism of action. An in vitro binding assay revealed that IMM01 has a strong binding affinity to CD47 with an EC50 of 0.4967 nM. IMM01 can induce strong ADCP and moderate ADCC, but not CDC. IMM01-induced strong phagocytosis against tumor cells was attributed to dual activities of blocking the "don't eat me" signal and activating the "eat me" signal, and IMM01 exhibits strong and robust in vivo anti-tumor activities either as monotherapy on hematological malignancies, or in combination therapy with PD-L1 monoclonal antibody (mAb), PD-1 mAb, and HER-2 mAb on solid tumors. Finally, IMM01 demonstrated a favorable safety profile with no human RBC binding activity or hemagglutination induction. IMM01 inhibits the growth of tumor cells by the following three possible mechanisms: (1) directly activating macrophages to phagocytize tumor cells; (2) activated macrophages degrade phagocytized tumor cells and present tumor antigens to T cells through MHC molecules to activate T cells; (3) activated macrophages can convert "cold tumors" into "hot tumors" and increase the infiltration of immune cells through chemotaxis by secreting some cytokines and chemokines.


Assuntos
Antígeno CD47 , Neoplasias , Fagocitose , Animais , Camundongos , Neoplasias/tratamento farmacológico , Transdução de Sinais , Proteínas Recombinantes de Fusão/farmacologia , Receptores Imunológicos
12.
Gastroenterol Rep (Oxf) ; 10: goac066, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36381223

RESUMO

Background: The prevalence of zinc deficiency is high in patients with chronic liver disease, but few studies have hitherto explored the relationship between the serum zinc level and hepatitis B virus (HBV)-related acute-on-chronic liver failure (ACLF). This study aimed to assess the association between zinc deficiency and infectious complications, and model for end-stage liver disease (MELD) score in patients with HBV-related ACLF. Methods: Patients with HBV-related ACLF from the Department of Infectious Diseases of the Third Affiliated Hospital of Sun Yat-sen University (Guangzhou, China) between January 2019 and December 2019 were retrospectively analysed in this study. Their demographic, clinical, and laboratory data were retrieved from the hospital information system and analysed. The Student's t-test was used for normally distributed continuous variables between two groups and the Chi-square test was used for categorical data. Univariate and multivariate logistic regression analyses were applied to identify independent parameters. Results: A total of 284 patients were included in this study, including 205 liver cirrhosis and 79 non-cirrhosis patients. The proportion of patients with zinc deficiency was the highest (84.5%), followed by subclinical zinc deficiency (14.1%) and normal zinc level (1.4%). Patients in the zinc deficiency group had a higher MELD score than the subclinical zinc deficiency or normal zinc group (P = 0.021). Age, total bilirubin, and serum zinc level were independent factors for infection (Ps < 0.05). The serum zinc level in patients without complications at admission was significantly higher than that in patients with complications (P = 0.004). Moreover, the serum zinc level in patients with prothrombin time activity (PTA) of <20% was significantly lower than that in patients with 20% ≤ PTA < 30% (P = 0.007) and that in patients with 30% ≤ PTA < 40% (P < 0.001). Conclusions: Zinc deficiency is common in patients with HBV-related ACLF. Zinc deficiency is closely associated with infectious complications and MELD score in patients with HBV-related ACLF.

13.
Neurotoxicology ; 94: 1-10, 2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36334642

RESUMO

Ketamine, a popular anesthetic, is often abused by people for its hallucinogenic effect. Thus, the safety of ketamine in pediatric populations has been called into question for potential neurotoxic effects. However, ketamine also has neuroprotective effects in many brain injury models. The differentiation of neural stem cells (NSCs) was influenced significantly by ketamine, but the molecular mechanism is still unclear. NSCs were extracted from the hippocampi of postnatal day 1 rats and treated with ketamine to induce NSCs differentiation. Our results found that ketamine promoted neuronal differentiation of NSCs dose-dependently in a small dose range (P < 0.001). The main types of neurons from NSCs were cholinergic (51 ± 4 %; 95 % CI: 41-61 %) and glutamatergic neurons (34 ± 3 %; 95 % CI: 27-42 %). Furthermore, we performed RNA sequencing to promise a more comprehensive understanding of the molecules regulated by ketamine. Finally, we combined bioimaging and multiple molecular biology techniques to clarify that ketamine influences NSC differentiation by regulating transient receptor potential canonical 3 (TRPC3) expressions. Ketamine dramatically repressed TRPC3 expression (MD [95 % CI]=0.67 [0.40-0.95], P < 0.001) with a significant increase of phosphorylated glycogen synthase kinase 3ß (p-GSK3ß; MD [95 % CI]=1.00 [0.74-1.27], P < 0.001) and a decrease of ß-catenin protein expression (MD [95 % CI]=0.60 [0.32-0.89], P = 0.001), thereby promoting the differentiation of NSCs into neurons and inhibiting their differentiation into astrocytes. These results suggest that TRPC3 is necessary for ketamine to modulate NSC differentiation, which occurs partly via regulation of the GSK3ß/ß-catenin pathway.

14.
Curr Oncol ; 29(11): 8650-8667, 2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36421335

RESUMO

OBJECTIVE: Kruppel-associated box (KRAB) proteins reportedly play a dual role in neoplastic transformation. At present, little is known about the function of the proteins encoded by the human pogo transposable element derived with KRAB domain (POGK) gene. Herein, we evaluated the prognostic significance of POGK expression in patients with hepatocellular carcinoma (HCC). METHODS: The data of HCC patients was downloaded from The Cancer Genome Atlas (TCGA) database. To determine the relationship between POGK and clinical features, logistic regression was applied. Cox regression and Kaplan-Meier analyses were used to evaluate the correlation between POGK and survival rates. Gene ontology (GO) analysis and Gene set enrichment analysis (GSEA) were conducted to identify the enriched pathways and functions associated with POGK. RESULTS: A total of 374 HCC patients were identified in TCGA. POGK was significantly upregulated in HCC and correlated with tumor status (p = 0.036), race (p = 0.025), weight (p = 0.002), body mass index (p = 0.033), histologic grade (p < 0.001), and alpha-fetoprotein (p < 0.001). High POGK expression in HCC patients correlated with a poor outcome in terms of overall survival (p = 0.0018), progression-free survival (p = 0.0087), relapse-free survival (p = 0.045), and disease-specific survival (p = 0.014), according to Kaplan-Meier analysis. Receiver operating characteristic curve analysis showed that the area under the curve of POGK expression for HCC diagnosis was 0.891. GSEA showed that high POGK expression might activate mitotic prometaphase, kinesins, homologous DNA pairing and strand exchange, MET activates PTK2 signaling pathway, G1 to S cell cycle control, Aurora B pathway, ncRNAs involved in WNT signaling pathway, hepatitis C, and ncRNAs involved in the STAT3 signaling pathway. POGK expression correlated with the abundance of adaptive and innate immunocytes in HCC. CONCLUSION: High expression of POGK has high diagnostic and prognostic values in patients with HCC. Moreover, POGK expression is correlated with immune infiltration in HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Regulação Neoplásica da Expressão Gênica , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Recidiva Local de Neoplasia/genética , Prognóstico
15.
Pediatr Surg Int ; 39(1): 17, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36449181

RESUMO

BACKGROUND: Patients with high-risk neuroblastoma (NB) have a poor prognosis. The prognostic significance of inflammatory biomarker-based nomograms for children with NB has not been previously studied. METHODS: Part of patients diagnosed with NB in our center from January 2016 to March 2022 were included in the study. Inflammatory biomarkers were primary outcome measures, including C-reactive protein (CRP), ferritin, neutrophil to lymphocyte ratio (NLR), and lymphocyte to monocyte ratio (LMR), platelet to lymphocyte ratio (PLR) and systemic immune-inflammation index (SII). Univariate and multivariate survival analyses were performed to assess the prognostic value of these indicators for overall survival (OS) in NB children, showing the Kaplan-Meier survival curves and plotting the nomogram. C-index were used to detect predictability. RESULTS: 93 NB patients were retrospectively analyzed. CRP, ferritin, NLR, PLR, and SII were significantly associated with OS of NB patients, while LMR were found to be not predictive of OS for NB patients. The established nomogram is well-calibrated, and the C-index is 0.731. CONCLUSION: Survival analysis found part of inflammatory biomarkers related to the prognosis of NB. The nomogram could be used as a convenient predictive tool in clinical practice to evaluate the prognosis of NB children at first diagnosis.


Assuntos
Neuroblastoma , Nomogramas , Criança , Humanos , Estudos Retrospectivos , Prognóstico , Biomarcadores , Neuroblastoma/diagnóstico , Proteína C-Reativa , Ferritinas , Inflamação
16.
Environ Res ; 217: 114913, 2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36427633

RESUMO

To address the drinking safety problems associated with high arsenic(III) (As(III)) and bacteria in underground water, core-shell Fe-Ag@AgCl nanowires were synthesized and exhibited excellent photocatalytic oxidation effects on co-existing As(III) and Escherichia coli (E. coli). With the introduction of Fe, the nanowires that were used 5 times could be easily magnetically collected, and the As(III) oxidation effect of these re-chlorinated nanowires increased from 39% to 60%. E. coli was completely inactivated within 60 min without photoreactivation after 20 min. Extracellular polymeric substances have play a protective role in the disinfection process. Quenching testing results confirmed that, except for the superoxide radical (•O2-), the subdominant active species were different for different objects: hole (hVB+) to As(III) and hydroxyl radical (•OH) to E. coli. Therefore the system with co-existing As(III) and E. coli, the inactivation effect of Fe-Ag@AgCl on E. coli decreased remarkably with an increase in As(III) concentration, while the oxidation process of As(III) was not significantly affected by E. coli until E. coli was increased to 108 cfu/mL. The photocatalytic process of co-existing As(III) and E. coli is displayed in a schematic diagram and was tested using desired results obtained from field groundwater in Xiantao City, Hubei Province. The function of Fe in band structures and density of states was analyzed using plane-wave density functional theory. These magnetic nanowires presented excellent photocatalytic ability on co-existing As(III) and E. coli, and provided new insights into drinking water safety in high-arsenic areas.

17.
Front Microbiol ; 13: 950677, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36274694

RESUMO

Ammonia-oxidizing archaea (AOA) and bacteria (AOB) play an important role in nitrification, which is essential in the global nitrogen cycle. However, their dynamics and the underlying community processes in agricultural ecosystems under disturbance remain largely unknown. In this study we examined the spatiotemporal dynamics of AOA and AOB communities and analyzed their community processes in the sediment of aquaculture ponds across three different areas in China. We found some significant temporal changes in AOA and AOB community diversity and abundances, but no temporal changes in community composition, despite the significant variations in sediment properties between different sampling times. Nevertheless, significant differences were found for AOA and AOB communities between different areas. Distinct area-specific taxa were detected, and they were found to be important in determining the response of AOA and AOB communities to environmental factors. In addition, geographic distance was found to be significantly correlated with AOA and AOB community composition, which demonstrates that dispersal limitation could significantly contribute to the variations in AOA and AOB communities, and stochastic processes were found to be important in structuring AOA/AOB communities in aquaculture ponds. Taken together, our study indicates that the dynamics of AOA and AOB are based on their community characteristics in aquaculture pond sediment. Our results, for the first time, provide evidence for the dynamics of AOA and AOB communities being driven by stochastic factors in a disturbed environment, and might also be of use in the management of the aquaculture environment.

18.
Ecotoxicol Environ Saf ; 246: 114146, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36215880

RESUMO

Ochratoxin A (OTA) is one of the most common and deleterious mycotoxins found in food and feedstuffs worldwide; however, Apiotrichum mycotoxinivorans can detoxify OTA. Our results show that A. mycotoxinivorans GUM1709 efficiently degraded OTA, but it caused the accumulation of intracellular reactive oxygen species. The main aim of this study was to identify potential OTA-detoxifying enzymes and to explore the effects of OTA on A. mycotoxinivorans GMU1709. RNA-seq data revealed that 1643 and 1980 genes were significantly upregulated and downregulated, respectively, after OTA exposure. Functional enrichment analyses indicated that OTA exposure enhanced defense capability, protein transport, endocytosis, and energy metabolism; caused ribosomal stress; suppressed DNA replication and transcription; inhibited cell growth and division; and promoted cell death. The integration of secretome, gene expression, and molecular docking analyses revealed that two carboxypeptidase homologues (members of the metallocarboxypeptidase family) were most likely responsible for the detoxification of both extracellular and intracellular OTA. Superoxide dismutase and catalase were the main genes activated in response to oxidative stress. In addition, analysis of key genes associated with cell division and apoptosis showed that OTA exposure inhibited mitosis and promoted cell death. This study revealed the possible OTA response and detoxification mechanisms in A. mycotoxinivorans.


Assuntos
Basidiomycota , Ocratoxinas , DNA Fúngico/metabolismo , DNA Fúngico/farmacologia , Simulação de Acoplamento Molecular , Ocratoxinas/toxicidade , Estresse Oxidativo/genética , Basidiomycota/metabolismo , Perfilação da Expressão Gênica , Expressão Gênica
19.
Bioresour Technol ; : 128094, 2022 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-36220530

RESUMO

Direct production of 5-hydroxymethylfurfural (HMF) through biomass always needs the addition of exogenous catalysts and causes extra costs. Herein, acid mine drainage (AMD), one of the traditional wastewaters, was introduced as a natural catalyst to produce HMF directly from lignocellulosic biomass. Key factors in the biomass conversion were optimized and investigated by the response surface methodology (RSM), and the HMF yield reached 13.51 wt% under optimal conditions. The metal elements and the acidic environment in AMD activated the Fenton reaction to effectively destroy the lignocellulose structure and synergistically promote the formation of HMF. Furthermore, the biomass substrate in the biomass conversion was indirectly modified by the AMD during this process. The biomass conversion residue could be prepared by pyrolysis to obtain a functional metal-loaded carbon material with good adsorption of thiamethoxam (THX), which provides a sustainable solution for the disposal of biomass conversion residue.

20.
Opt Express ; 30(22): 40357-40366, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36298970

RESUMO

We demonstrate that reflectionless propagation of electromagnetic waves between two different materials can be achieved by designing an intermediate temporal medium, which can work in an ultra-wide frequency band. Such a temporal medium is designed with consideration of a multi-stage variation of the material's permittivity in the time domain. The multi-stage temporal permittivity is formed by a cascaded quarter-wave temporal coating, which is an extension of the antireflection temporal coating by Pacheco-Peña et al. [Optica7, 323 (2020)10.1364/OPTICA.381175]. The strategy to render ultra-wideband antireflection temporal medium is discussed analytically and verified numerically. In-depth analysis shows that the multi-stage design of the temporal media implies a continuously temporal variation of the material's constitutive parameters, thus an ultra-wideband antireflection temporal medium is reasonably obtained. As an illustrative example for application, the proposed temporal medium is adopted to realize impedance matching between a dielectric slab and free space, which validates our new findings.

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