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1.
Phys Rev E ; 109(6-2): 065213, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39020969

RESUMO

The normal modes, i.e., the eigensolutions to the dispersion relation equation, are the most fundamental properties of a plasma. The real part indicates the intrinsic oscillation frequency while the imaginary part the Landau damping rate. In most of the literature, the normal modes of quantum plasmas are obtained by means of small damping approximation, which is invalid for high-k modes. In this paper, we solve the exact dispersion relations via the analytical continuation scheme, and, due to the multi-value nature of the Fermi-Dirac distribution, reformation of the complex Riemann surface is required. It is found that the topological shape of the root locus in quantum plasmas is quite different from classical ones, in which both real and imaginary frequencies of high-k modes increase with k steeper than the typical linear behavior in classical plasmas. As a result, the time-evolving behavior of a high-k initial perturbation becomes ballistic-like in quantum plasmas.

2.
J Mol Med (Berl) ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953935

RESUMO

Diabetes mellitus (DM), an important public health problem, aggravates the global economic burden. Diabetic encephalopathy (DE) is a serious complication of DM in the central nervous system. Metformin has been proven to improve DE. However, the mechanism is still unclear. In this study, the db/db mice, a common model used for DE, were employed to explore and study the neuroprotective effect of metformin and related mechanisms. Behavioral tests indicated that metformin (100 or 200 mg/kg/day) could significantly improve the learning and memory abilities of db/db mice. The outcomes from the oral glucose tolerance test (OGTT) and insulin tolerance test (ITT) demonstrate that metformin effectively modulates glucose and insulin signaling pathways in db/db mice. The results of body weight and blood lipid panel (total cholesterol, triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol) show that metformin promotes the level of lipid metabolism in db/db mice. Furthermore, data from oxidative stress assays, which measured levels of malondialdehyde, superoxide dismutase, catalase, and glutathione peroxidase, suggest that metformin suppresses oxidative stress-induced brain damage in db/db mice. In addition, western blot, Nissl staining, and immunofluorescence results showed that metformin increased the expressions of nerve growth factor and postsynaptic density 95 and repaired neuronal structural damage. For the mechanism study, metformin activated SIRT1 and inhibited the expression of NLRP3 inflammasome (NLRP3, ASC, caspase-1, IL-1ß, and IL-18) and inflammatory cytokines (TNFα and IL-6). In conclusion, metformin could ameliorate cognitive dysfunction through the SIRT1/NLRP3 pathway, which might be a promising mechanism for DE treatment.

3.
J Soc Psychol ; : 1-19, 2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38852171

RESUMO

Familiar information is more likely to be accepted as true. This illusory truth effect has a tremendous negative impact on misinformation intervention. Previous studies focused on the familiarity from repeated exposure in the laboratory, ignoring preexisting familiarity with real-world misinformation. Over three studies (total N = 337), we investigated the cognitive mechanisms behind the truth biases from these two familiarity sources, and whether fact-checking can curb such biased truth perceptions. Studies 1 and 2 found robust truth effects induced by two sources of familiarity but with different cognitive processes. According to the cognitive process model, repetition-induced familiarity reduced decision prudence. Preexisting familiarity instead enhanced truth-congruent evidence accumulation. Study 3 showed that pre-exposing statements with warning flags eliminated the bias to truth induced by repetition but not that from preexisting familiarity. These repeated statements with warning labels also reduced decision caution. These findings furthered the understanding of how different sources of familiarity affect truth perceptions and undermine the intervention through different cognitive processes.

4.
Infect Dis Poverty ; 13(1): 43, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38863070

RESUMO

BACKGROUND: The strong invasiveness and rapid expansion of dengue virus (DENV) pose a great challenge to global public health. However, dengue epidemic patterns and mechanisms at a genetic scale, particularly in term of cross-border transmissions, remain poorly understood. Importation is considered as the primary driver of dengue outbreaks in China, and since 1990 a frequent occurrence of large outbreaks has been triggered by the imported cases and subsequently spread to the western and northern parts of China. Therefore, this study aims to systematically reveal the invasion and diffusion patterns of DENV-1 in Guangdong, China from 1990 to 2019. METHODS: These analyses were performed on 179 newly assembled genomes from indigenous dengue cases in Guangdong, China and 5152 E gene complete sequences recorded in Chinese mainland. The genetic population structure and epidemic patterns of DENV-1 circulating in Chinese mainland were characterized by phylogenetics, phylogeography, phylodynamics based on DENV-1 E-gene-based globally unified genotyping framework. RESULTS: Multiple serotypes of DENV were co-circulating in Chinese mainland, particularly in Guangdong and Yunnan provinces. A total of 189 transmission clusters in 38 clades belonging to 22 subgenotypes of genotype I, IV and V of DENV-1 were identified, with 7 Clades of Concern (COCs) responsible for the large outbreaks since 1990. The epidemic periodicity was inferred from the data to be approximately 3 years. Dengue transmission events mainly occurred from Great Mekong Subregion-China (GMS-China), Southeast Asia (SEA), South Asia Subcontinent (SASC), and Oceania (OCE) to coastal and land border cities respectively in southeastern and southwestern China. Specially, Guangzhou was found to be the most dominant receipting hub, where DENV-1 diffused to other cities within the province and even other parts of the country. Genome phylogeny combined with epidemiological investigation demonstrated a clear local consecutive transmission process of a 5C1 transmission cluster (5C1-CN4) of DENV-1 in Guangzhou from 2013 to 2015, while the two provinces of Guangdong and Yunnan played key roles in ongoing transition of dengue epidemic patterns. In contextualizing within Invasion Biology theories, we have proposed a derived three-stage model encompassing the stages of invasion, colonization, and dissemination, which is supposed to enhance our understanding of dengue spreading patterns. CONCLUSIONS: This study demonstrates the invasion and diffusion process of DENV-1 in Chinese mainland within a global genotyping framework, characterizing the genetic diversities of viral populations, multiple sources of importation, and periodic dynamics of the epidemic. These findings highlight the potential ongoing transition trends from epidemic to endemic status offering a valuable insight into early warning, prevention and control of rapid spreading of dengue both in China and worldwide.


Assuntos
Vírus da Dengue , Dengue , Genótipo , Filogenia , Sorogrupo , Vírus da Dengue/genética , Vírus da Dengue/classificação , Vírus da Dengue/fisiologia , China/epidemiologia , Dengue/epidemiologia , Dengue/virologia , Dengue/transmissão , Humanos , Surtos de Doenças , Filogeografia , Genoma Viral
5.
BMC Complement Med Ther ; 24(1): 239, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38890651

RESUMO

BACKGROUND: Insomnia is common in college students, but its impact on health and wellbeing is often neglected. Enhancing sleep quality through targeted interventions could improve overall health and reduce the risk of consequent co-morbidities and mental health problems. Qigong exercises have been shown to significantly improve sleep quality and relieve insomnia. Three-circle Post Standing (TCPS) can help integrate body, breath, and mind, a fundamental principle of Qigong that promotes holistic wellbeing. In this clinical trial, we aim to (1) evaluate the feasibility, safety, and therapeutic efficacy of administering TCPS to improve sleep quality and quality of life in college students with insomnia; (2) explore the neurophysiological mechanisms underlying the mind adjustments mediated by TCPS in insomnia; (3) investigate body and breath pathophysiology mediated by TCPS in insomnia; and (4) assess the long-term efficacy of TCPS in terms of sleep quality and quality of life. METHODS: This will be a prospective, parallel, four-arm, double-blind randomized controlled trial to investigate the effects and underlying mechanisms of TCPS on college students with insomnia. One hundred college students meeting diagnostic criteria for insomnia will be randomly assigned to receive either 14 weeks of standardized TCPS training (two weeks of centralized training followed by 12 weeks of supervised training) or sham-control Post Standing training. Efficacy outcomes including sleep quality, quality of life, neurophysiological assessments, plantar pressure, biomechanical balance, and physical measures will be collected at baseline, eight weeks (mid-point of supervised training), and 14 weeks (end of supervised training). Sleep quality and quality of life will also be evaluated during the four- and eight-week follow-up. DISCUSSION: This trial will be an important milestone in the development of new therapeutic approaches for insomnia and should be easily implementable by college students with insomnia. The neuro- and pathophysiological assessments will provide new insights into the mechanisms underlying TCPS. CLINICAL TRIAL REGISTRATION: This trial has been registered in the China Clinical Trials Registry (registration number: ChiCTR2400080763).


Assuntos
Qigong , Distúrbios do Início e da Manutenção do Sono , Estudantes , Humanos , Distúrbios do Início e da Manutenção do Sono/terapia , Qigong/métodos , Método Duplo-Cego , Universidades , Adulto Jovem , Qualidade de Vida , Estudos Prospectivos , Masculino , Adulto , Feminino , Qualidade do Sono
6.
Pharmacotherapy ; 44(7): 539-548, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38899757

RESUMO

BACKGROUND: To compare the effects of proton pump inhibitor (PPI) and histamine-2 receptor antagonist (H2RA) use on the occurrence of acute kidney injury (AKI) in septic patients at high risk for developing stress ulcers. METHODS: Using the Medical Information Mart for Intensive Care IV version 2.2 database, septic patients with high-risk factors for stress ulcers (i.e., shock, coagulopathy, invasive mechanical ventilation, or chronic liver diseases) were included. Exposures included PPIs and H2RAs within 24 h of intensive care unit (ICU) admission or prior to ICU admission. The primary end point was severe sepsis-associated AKI as defined by the Kidney Disease Improving Global Outcomes criteria stage 3 (KDIGO-3). Propensity score matching (PSM) was performed to balance baseline characteristics. Multivariable Cox proportional hazards regression was used to estimate the effect size. RESULTS: 4731 PPI users and 4903 H2RA users were included. After PSM, there were 1785 pairs exposed to PPIs and H2RAs. In the PSM cohort, the cumulative incident KDIGO-3 rate was higher in the PPI group than in the H2RA group (log-rank test, p = 0.009). Regression analyses showed that PPI exposure [adjusted hazard ratio 1.32, 95% confidence interval (CI) 1.11-1.58, p = 0.002] was associated with incident KDIGO-3 compared with H2RA use. This association remained consistent in sensitivity analyses. Additionally, the PPI group had a higher need for kidney replacement therapy compared with the H2RA group (3.6% vs. 2.1%, P = 0.012). CONCLUSIONS: Among septic patients at high risk for developing stress ulcers, PPI exposure was associated with incident KDIGO-3 AKI compared with H2RA use.


Assuntos
Injúria Renal Aguda , Antagonistas dos Receptores H2 da Histamina , Inibidores da Bomba de Prótons , Sepse , Humanos , Inibidores da Bomba de Prótons/efeitos adversos , Inibidores da Bomba de Prótons/administração & dosagem , Inibidores da Bomba de Prótons/uso terapêutico , Antagonistas dos Receptores H2 da Histamina/uso terapêutico , Antagonistas dos Receptores H2 da Histamina/efeitos adversos , Masculino , Feminino , Sepse/complicações , Pessoa de Meia-Idade , Idoso , Fatores de Risco , Unidades de Terapia Intensiva , Estudos Retrospectivos , Pontuação de Propensão , Úlcera Péptica/complicações , Úlcera Péptica/tratamento farmacológico , Estudos de Coortes
7.
Zhongguo Zhong Yao Za Zhi ; 49(10): 2783-2797, 2024 May.
Artigo em Chinês | MEDLINE | ID: mdl-38812179

RESUMO

Dihuang Baoyuan Granules is a prescription endorsed by HU Tianbao, a renowned and elderly Chinese medicine practitioner from Beijing, and has demonstrated definite clinical efficacy. The composition of this prescription is intricate as it includes 7 distinct herbal medicines. This study aims to analyze the chemical composition of Dihuang Baoyuan Granules, evaluate its efficacy in the treatment of diabetes and analyze the distribution of the drug components in the plasma, liver, and kidney after administration. The findings will serve as a reference for future research on pharmacodynamic substances of this prescription. UHPLC-LTQ-Orbitrap MS was employed to analyze the main chemical components of Dihuang Baoyuan Granules. A Waters ACQUITY Premier HSS T3 column(2.1 mm×100 mm, 1.8 µm) was used for chromatographic separation with 0.1% formic acid(A)-acetonitrile(B) as the mobile phases in a gradient elution at a flow rate of 0.3 mL·min~(-1). Electrospray ionization(ESI) source was used to acquire data in positive and negative ion modes. Furthermore, a rat model of diabetes mellitus was established by feeding with a high-sugar high-fat diet, and injection with streptozocin at a dose of 35 mg·kg~(-1), and the modeled rats were then administrated with Dihuang Baoyuan Granules. The fasting blood glucose, hemoglobin A1c, and other relevant indicators were measured, and the substances present in the plasma, liver, and kidney were identified. By reference to quasi-molecular ions, MS/MS fragment ions, MS spectra of reference substances, and compound information in available reports, 191 components were identified in Dihuang Baoyuan Granules, including 29 alkaloids, 24 flavonoids, 22 organic acids, 16 amino acids, 12 terpenes, 11 steroid saponins, 9 sugars, 8 phenylethanoid glycosides, 8 nucleosides, 2 phenylpropanoids, and 49 others compounds. Eighty-three chemical components were identified in rat plasma, 109 in the liver, and 98 in the kidney. Component identification and characterization of Dihuang Baoyuan Granules in vitro and in vivo provide efficacy information and guidance for the basic research on the pharmacodynamic substances and further clinical application of this prescription.


Assuntos
Medicamentos de Ervas Chinesas , Ratos Sprague-Dawley , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacocinética , Cromatografia Líquida de Alta Pressão/métodos , Animais , Ratos , Masculino , Humanos , Fígado/efeitos dos fármacos , Fígado/química , Fígado/metabolismo , Espectrometria de Massas/métodos , Rim/efeitos dos fármacos , Rim/química , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus/tratamento farmacológico
8.
Biomolecules ; 14(5)2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38785984

RESUMO

Protein ubiquitination is an enzymatic cascade reaction and serves as an important protein post-translational modification (PTM) that is involved in the vast majority of cellular life activities. The key enzyme in the ubiquitination process is E3 ubiquitin ligase (E3), which catalyzes the binding of ubiquitin (Ub) to the protein substrate and influences substrate specificity. In recent years, the relationship between the subfamily of neuron-expressed developmental downregulation 4 (NEDD4), which belongs to the E3 ligase system, and digestive diseases has drawn widespread attention. Numerous studies have shown that NEDD4 and NEDD4L of the NEDD4 family can regulate the digestive function, as well as a series of related physiological and pathological processes, by controlling the subsequent degradation of proteins such as PTEN, c-Myc, and P21, along with substrate ubiquitination. In this article, we reviewed the appropriate functions of NEDD4 and NEDD4L in digestive diseases including cell proliferation, invasion, metastasis, chemotherapeutic drug resistance, and multiple signaling pathways, based on the currently available research evidence for the purpose of providing new ideas for the prevention and treatment of digestive diseases.


Assuntos
Ubiquitina-Proteína Ligases Nedd4 , Ubiquitinação , Humanos , Ubiquitina-Proteína Ligases Nedd4/metabolismo , Ubiquitina-Proteína Ligases Nedd4/genética , Doenças do Sistema Digestório/metabolismo , Doenças do Sistema Digestório/patologia , Animais , Transdução de Sinais , Proliferação de Células , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética
9.
J Infect Dev Ctries ; 18(4): 501-503, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38728635

RESUMO

We proposed that the pharynx, as a common organ of the respiratory and digestive tracts, may be a respiratory and digestive tract cross cryptic transmission pathway for 2019-nCoV infection from the nasal cavities to the pharynx and lung, then to nasal cavities by aerosol (respiratory route) to the pharynx and the gastrointestinal tract, then to the oral cavity by feces (fecal-oral route) and to pharynx, lungs, or gastrointestinal tract.


Assuntos
COVID-19 , Faringe , SARS-CoV-2 , Humanos , COVID-19/transmissão , Faringe/virologia , Infecção Hospitalar/transmissão , Trato Gastrointestinal/virologia , Fezes/virologia , Fezes/microbiologia , Infecções Respiratórias/transmissão , Infecções Respiratórias/virologia
10.
Anal Chem ; 96(15): 6045-6054, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38569073

RESUMO

Plastic pollution pervades natural environments and wildlife. Consequently, high-throughput detection methods for plastic debris are urgently needed. A novel method was developed to detect plastic debris larger than 0.5 mm, which integrated an extraction method with low organic loss and plastic damage alongside a classification method for fused images. This extraction method broadened the size range of the remaining plastic debris, while the fusion solved the low spatial resolution of hyperspectral images and the absence of spectral information in red-green-blue (RGB) images. This method was validated for plastic debris in digestate, compost, and sludge, with extraction demonstrating 100% recovery rates for all samples. After fusion, the spatial resolution of hyperspectral images was improved about five times. Classification recall for the fused hyperspectral images achieved 97 ± 8%, surpassing 83 ± 29% of the raw images. Application of this method to solid digestate detected 1030 ± 212 items/kg of plastic debris, comparable with the conventional Fourier transform infrared spectroscopic result of 1100 ± 436 items/kg. This developed method can investigate plastic debris in complex matrices, simultaneously addressing a wide range of sizes and types. This capability helps acquire reliable data to predict secondary microplastic generation and conduct a risk assessment.

11.
Front Microbiol ; 15: 1380912, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38655090

RESUMO

Background: There is growing evidence of associations between the gut microbiota and anxiety disorders, where changes in gut microbiotas may affect brain function and behavior via the microbiota-gut-brain axis. However, population-level studies offering a higher level of evidence for causality are lacking. Our aim was to investigate the specific gut microbiota and associated metabolites that are closely related to anxiety disorders to provide mechanistic insights and novel management perspectives for anxiety disorders. Method: This study used summary-level data from publicly available Genome-Wide Association Studies (GWAS) for 119 bacterial genera and the phenotype "All anxiety disorders" to reveal the causal effects of gut microbiota on anxiety disorders and identify specific bacterial genera associated with anxiety disorders. A two-sample, bidirectional Mendelian randomization (MR) design was deployed, followed by comprehensive sensitivity analyses to validate the robustness of results. We further conducted multivariable MR (MVMR) analysis to investigate the potential impact of neurotransmitter-associated metabolites, bacteria-associated dietary patterns, drug use or alcohol consumption, and lifestyle factors such as smoking and physical activity on the observed associations. Results: Bidirectional MR analysis identified three bacterial genera causally related to anxiety disorders: the genus Eubacterium nodatum group and genus Ruminococcaceae UCG011 were protective, while the genus Ruminococcaceae UCG011 was associated with an increased risk of anxiety disorders. Further MVMR suggested that a metabolite-dependent mechanism, primarily driven by tryptophan, tyrosine, phenylalanine, glycine and cortisol, which is consistent with previous research findings, probably played a significant role in mediating the effects of these bacterial genera to anxiety disorders. Furthermore, modifying dietary pattern such as salt, sugar and processed meat intake, and adjusting smoking state and physical activity levels, appears to be the effective approaches for targeting specific gut microbiota to manage anxiety disorders. Conclusion: Our findings offer potential avenues for developing precise and effective management approaches for anxiety disorders by targeting specific gut microbiota and associated metabolites.

12.
Adv Mater ; 36(28): e2402780, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38661112

RESUMO

The high cost of proton exchange membrane water electrolysis (PEMWE) originates from the usage of precious materials, insufficient efficiency, and lifetime. In this work, an important degradation mechanism of PEMWE caused by dynamics of ionomers over time in anode catalyst layer (ACL), which is a purely mechanical degradation of microstructure, is identified. Contrary to conventional understanding that the microstructure of ACL is static, the micropores are inclined to be occupied by ionomers due to the localized swelling/creep/migration, especially near the ACL/PTL (porous transport layer) interface, where they form transport channels of reactant/product couples. Consequently, the ACL with increased ionomers at PTL/ACL interface exhibit rapid and continuous degradation. In addition, a close correlation between the microstructure of ACL and the catalyst ink is discovered. Specifically, if more ionomers migrate to the top layer of the ink, more ionomers accumulate at the ACL/PEM interface, leaving fewer ionomers at the ACL/PTL interface. Therefore, the ionomer distribution in ACL is successfully optimized, which exhibits reduced ionomers at the ACL/PTL interface and enriches ionomers at the ACL/PEM interface, reducing the decay rate by a factor of three when operated at 2.0 A cm-2 and 80 °C. The findings provide a general way to achieve low-cost hydrogen production.

13.
Org Lett ; 26(10): 2051-2056, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38436250

RESUMO

A one-pot gold-catalyzed acyl migration followed by ytterbium-catalyzed asymmetric Friedel-Crafts alkylation is disclosed, leading to the rapid synthesis of chiral dihydrocarbazoles and dihydrodibenzofuran in generally moderate to good overall yields with good to excellent enantioselectivities. The gold-catalyzed acyl migration of propargyl acetates generates α-ylidene-ß-diketones with high E/Z ratios, which are then subjected to the ytterbium-catalyzed asymmetric Friedel-Crafts alkylation without any purification. Importantly, this protocol provides a new type of substrate for asymmetric Friedel-Crafts alkylation.

14.
Zookeys ; 1193: 145-160, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38487668

RESUMO

The genus Svistella Gorochov, 1987 includes 10 species from Asia, with nine documented in China. In this study, a new species, Svistellayayun He, sp. nov., is described from Xizang, China. Morphologically, it resembles S.rufonotata (Chopard, 1932) but can be distinguished by a smaller inner tympanum, dark-brown setae on the 5th segment of the maxillary palp, and a rounded apex on the ectoparamere. To validate our morphological inferences and support the description of S.yayunsp. nov. as a new species, we performed a PCA based on bioacoustics parameters and molecular analysis. All Svistella species documented in China are distinguished by integrating their songs and DNA barcoding.

15.
ACS Appl Mater Interfaces ; 16(13): 16408-16417, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38502312

RESUMO

The widespread application of proton exchange membrane water electrolyzers (PEMWEs) is hampered by insufficient lifetime caused by degradation of the anode catalyst layer (ACL). Here, an important degradation mechanism has been identified, attributed to poor mechanical stability causing the mass transfer channels to be blocked by ionomers under operating conditions. By using liquid-phase atomic force microscopy, we directly observed that the ionomers were randomly distributed (RD) in the ACL, which occupied the mass transfer channels due to swelling, creeping, and migration properties. Interestingly, we found that alternating treatments of the ACL in different water/temperature environments resulted in forming three-dimensional ionomer networks (3D INs) in the ACL, which increased the mechanical strength of microstructures by 3 times. Benefitting from the efficient and stable mass transfer channels, the lifetime was improved by 19 times. A low degradation rate of approximately 3.0 µV/h at 80 °C and a high current density of 2.0 A/cm2 was achieved on a 50 cm2 electrolyzer. These data demonstrated a forecasted lifetime of 80 000 h, approaching the 2026 DOE lifetime target. This work emphasizes the importance of the mechanical stability of the ACL and offers a general strategy for designing and developing a durable PEMWE.

16.
Huan Jing Ke Xue ; 45(3): 1692-1701, 2024 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-38471881

RESUMO

In rice-vegetable rotation systems in tropical areas, a large amount of nitrate nitrogen accumulates after fertilization in the melon and vegetable season, which leads to the leaching of nitrate nitrogen and a large amount of N2O emission after the seasonal flooding of rice, which leads to nitrogen loss and intensification of the greenhouse effect. How to improve the utilization rate of nitrate nitrogen and reduce N2O emissions has become an urgent problem to be solved. Six treatments were set up [200 mg·kg-1 KNO3 (CK); 200 mg·kg-1 KNO3 + 2% biochar addition (B); 200 mg·kg-1 KNO3+1% peanut straw addition (P); 200 mg·kg-1 KNO3 + 2% biochar + 1% peanut straw addition (P+B); 200 mg·kg-1 KNO3 + 1% rice straw addition (R); 200 mg·kg-1 KNO3 + 2% biochar+1% rice straw addition (R+B)] and cultured at 25℃ for 114 d to explore the effects of organic material addition on greenhouse gas emissions and nitrogen use after flooding in high nitrate nitrogen soil. The results showed that compared with that in CK, adding straw or combining straw with biochar significantly increased soil pH (P<0.05). The B and P treatments significantly increased the cumulative N2O emissions by 41.6% and 28.5% (P<0.05), and the P+B, R, and R+B treatments significantly decreased the cumulative N2O emissions by 14.1%, 24.7%, and 36.7% (P<0.05), respectively. The addition of straw increased the net warming potential of greenhouse gases (NGWP). The addition of coir biochar significantly reduced the effect of straw on NGWP (P<0.05). The combined application of straw and biochar decreased NGWP, and P+B significantly decreased NGWP, but that with R+B was not significant (P>0.05). Adding straw or biochar significantly increased soil microbial biomass carbon (MBC) (P<0.05), and that of P+B was the highest (502.26 mg·kg-1). The combined application of straw and biochar increased soil microbial biomass nitrogen (MBN), and that of P+B was the highest. The N2O emission flux was negatively correlated with pH (P<0.01) and positively correlated with NH4+-N and NO3--N (P<0.01). The cumulative emission of N2O was negatively correlated with MBN (P<0.05). There was a significant negative correlation between NO3--N and MBN (P<0.01), indicating that the reduction in NO3--N was likely to be held by microorganisms, and the increase in the microbial hold of NO3--N also reduced N2O emission. In conclusion, the combined application of peanut straw and coconut shell biochar could significantly inhibit N2O emission and increase soil MBC and MBN, which is a reasonable measure to make full use of nitrogen fertilizer, reduce nitrogen loss, and slow down N2O emission after the season of Hainan vegetables.


Assuntos
Gases de Efeito Estufa , Oryza , Solo/química , Gases de Efeito Estufa/análise , Verduras , Agricultura/métodos , Nitratos , Nitrogênio , Óxido Nitroso/análise , Carvão Vegetal , China , Fertilizantes
17.
Huan Jing Ke Xue ; 45(2): 929-939, 2024 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-38471931

RESUMO

The effects of biochar application on soil nitrous oxide (N2O) and methane (CH4) emissions in a typical rice-vegetable rotation system in Hainan after two years were investigated. The aim was to clarify the long-term effects of biochar on greenhouse gas emissions under this model, and it provided a theoretical basis for N2O and CH4 emission reduction in rice-vegetable rotation systems in tropical regions of China. Four treatments were set up in the field experiment, including no nitrogen fertilizer control (CK); nitrogen, phosphorus, and potassium fertilizer (CON); nitrogen, phosphorus, and potassium fertilizer combined with 20 t·hm-2 biochar (B1); and nitrogen, phosphorus, and potassium fertilizer combined with 40 t·hm-2 biochar (B2). The results showed that: ① compared with that in the CON treatment, the B1 and B2 treatments significantly reduced N2O emissions by 32% and 54% in the early rice season (P < 0.05, the same below), but the B1 and B2 treatments significantly increased N2O emissions by 31% and 81% in the late rice season. The cumulative emissions of N2O in the pepper season were significantly higher than those in the early and late rice seasons, and the B1 treatment significantly reduced N2O emissions by 35%. There was no significant difference between the B2 and CON treatments. ② Compared with that in the CON treatment, B1 and B2 significantly reduced CH4 emissions by 63% and 65% in the early rice season, and the B2 treatment significantly increased CH4 emissions by 41% in the late rice season. There was no significant difference between the B1 and CON treatments. There was no significant difference in cumulative CH4 emissions between treatments in the pepper season. ③ The late rice season contributed to the main global warming potential (GWP) of the rice-vegetable rotation system, and CH4 emissions determined the magnitude of GWP and greenhouse gas emission intensity (GHGI). After two years of biochar application, B1 reduced the GHGI of the whole rice-vegetable rotation system, and B2 increased the GHGI and reached a significant level. However, the B1 and B2 treatments significantly reduced GHGI in the early rice season and pepper season, and only the B2 treatment increased GHGI in the late rice season. ④ Compared with that in the CON treatment, the B1 and B2 treatments significantly increased the yield of early rice by 33% and 51%, and the B1 and B2 treatments significantly increased the yield of pepper season by 53% and 81%. In the late rice season, there was no significant difference in yield except for in the CK treatment without nitrogen fertilizer. The results showed that the magnitude of greenhouse gas emissions in the tropical rice-vegetable rotation system was mainly determined by CH4 emissions in the late rice season. After two years of biochar application, only low biochar combined with nitrogen fertilizer had a significant emission reduction effect, but high and low biochar combined with nitrogen fertilizer increased the yield of early rice and pepper crops continuously.


Assuntos
Carvão Vegetal , Gases de Efeito Estufa , Oryza , Gases de Efeito Estufa/análise , Agricultura/métodos , Fertilizantes/análise , Solo , Nitrogênio , China , Metano/análise , Óxido Nitroso/análise , Fósforo , Verduras , Potássio
18.
Redox Biol ; 72: 103130, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38522110

RESUMO

Redox-responsive hydropersulfide prodrugs are designed to enable a more controllable and efficient hydropersulfide (RSSH) supply and to thoroughly explore their biological and therapeutic applications in oxidative damage. To obtain novel activation patterns triggered by redox signaling, we focused on NAD(P)H: quinone acceptor oxidoreductase 1 (NQO1), a canonical antioxidant enzyme, and designed NQO1-activated RSSH prodrugs. We also performed a head-to-head comparison of two mainstream structural scaffolds with solid quantitative analysis of prodrugs, RSSH, and metabolic by-products by LC-MS/MS, confirming that the perthiocarbamate scaffold was more effective in intracellular prodrug uptake and RSSH production. The prodrug was highly potent in oxidative stress management against cisplatin-induced nephrotoxicity. Strikingly, this prodrug possessed potential feedback activation properties by which the delivered RSSH can further escalate the prodrug activation via NQO1 upregulation. Our strategy pushed RSSH prodrugs one step further in the pursuit of efficient release in biological matrices and improved druggability against oxidative stress.


Assuntos
NAD(P)H Desidrogenase (Quinona) , Oxirredução , Estresse Oxidativo , Pró-Fármacos , Sulfetos , Pró-Fármacos/farmacologia , Pró-Fármacos/química , Estresse Oxidativo/efeitos dos fármacos , NAD(P)H Desidrogenase (Quinona)/metabolismo , Oxirredução/efeitos dos fármacos , Sulfetos/química , Sulfetos/farmacologia , Humanos , Animais , Espectrometria de Massas em Tandem , Cisplatino/farmacologia , Antioxidantes/farmacologia , Antioxidantes/química , Camundongos
19.
J Hazard Mater ; 469: 133965, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38471381

RESUMO

Cadmium (Cd) contamination in agricultural soil has been an elevated concern due to the high health risks associated with the transfer through the soil-food chain, particularly in the case of rice. Recently, there has numerous researches on the use of nanoparticle-loaded materials for heavy metal-polluted soil remediation, resulting in favorable outcomes. However, there has been limited research focus on the field-scale application and recovery. This study was aimed to validate the Cd reduction effect of the nano-FeS loaded lignin hydrogel composites (FHC) in mildly polluted paddies, and to propose a field-scale application method. Hence, a multi-site field experiment was conducted in southern China. After the application for 94-103 days, the FHC exhibited a high integrity and elasticity, with a recovery rate of 91.90%. The single-round remediation led to decreases of 0.42-31.72% in soil Cd content and 1.52-49.11% in grain Cd content. Additionally, this remediation technique did not adversely impact rice production. Consequently, applying FHC in the field was demonstrated to be an innovative, efficient, and promising remediation technology. Simultaneously, a strategy was proposed for reducing Cd levels while cultivating rice in mildly polluted fields using the FHC.


Assuntos
Oryza , Poluentes do Solo , Cádmio/análise , Lignina , Hidrogéis , Poluentes do Solo/análise , Solo
20.
J Nat Prod ; 87(2): 396-403, 2024 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-38330072

RESUMO

Six new sesquiterpene quinone/hydroquinone meroterpenoids, arenarialins A-F (1-6), were isolated from the marine sponge Dysidea arenaria collected from the South China Sea. Their chemical structures and absolute configurations were determined by HRMS and NMR data analyses coupled with DP4+ and ECD calculations. Arenarialin A (1) features an unprecedented tetracyclic 6/6/5/6 carbon skeleton, whereas arenarialins B-D (2-4) possess two rare secomeroterpene scaffolds. Arenarialins A-F showed inhibitory activity on the production of inflammatory cytokines TNF-α and IL-6 in LPS-induced RAW264.7 macrophages with arenarialin D regulating the NF-κB/MAPK signaling pathway.


Assuntos
Dysidea , Poríferos , Sesquiterpenos , Animais , Dysidea/química , Poríferos/química , Sesquiterpenos/farmacologia , Sesquiterpenos/química , Anti-Inflamatórios/farmacologia , NF-kappa B , Estrutura Molecular
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