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1.
J Colloid Interface Sci ; 677(Pt A): 459-469, 2025 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-39098279

RESUMO

High working voltage, large theoretical capacity and cheapness render Mn3O4 promising cathode candidate for aqueous zinc ion batteries (AZIBs). Unfortunately, poor electrochemical activity and bad structural stability lead to low capacity and unsatisfactory cycling performance. Herein, Mn3O4 material was fabricated through a facile precipitation reaction and divalent copper ions were introduced into the crystal framework, and ultra-small Cu-doped Mn3O4 nanocrystalline cathode materials with mixed valence states of Mn2+, Mn3+ and Mn4+ were obtained via post-calcination. The presence of Cu acts as structural stabilizer by partial substitution of Mn, as well as enhance the conductivity and reactivity of Mn3O4. Significantly, based on electrochemical investigations and ex-situ XPS characterization, a synergistic effect between copper and manganese was revealed in the Cu-doped Mn3O4, in which divalent Cu2+ can catalyze the transformation of Mn3+ and Mn4+ to divalent Mn2+, accompanied by the translation of Cu2+ to Cu0 and Cu+. Benefitting from the above advantages, the Mn3O4 cathode doped with moderate copper (abbreviated as CMO-2) delivers large discharge capacity of 352.9 mAh g-1 at 100 mA g-1, which is significantly better than Mn3O4 (only 247.8 mAh g-1). In addition, CMO-2 holds 203.3 mAh g-1 discharge capacity after 1000 cycles at 1 A g-1 with 98.6 % retention, and after 1000 cycles at 5 A g-1, it still performs decent discharge capacity of 104.2 mAh g-1. This work provides new ideas and approaches for constructing manganese-based AZIBs with long lifespan and high capacity.

2.
Appl Radiat Isot ; 214: 111531, 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39357257

RESUMO

99mTc is regarded as the most important medical isotope, and its supply issues have garnered significant attention. A simple and efficient separation method was performed for the production of 99mTc from 100Mo target in this study. The entire process involves accelerator irradiation, 99mTc/100Mo separation, and target material recovery. The key aspect is separation process, which including the high-temperature conversion of metal molybdenum targets and the selective solution of 99mTc with normal saline. This method can separate highly pure 99mTc within 1.5 h, with a separation efficiency exceeding 80%. The reagents used in the separation process are minimal, resulting in less radioactive waste. Additionally, the target material is easy to reclaim, with a recovery rate of over 95%.

3.
Environ Sci Technol ; 58(37): 16399-16409, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39235209

RESUMO

The cyclical variations in environmental temperature generated by natural rhythms constantly impact the wastewater treatment process through the aeration system. Engineering data show that fluctuations in environmental temperature cause the reactor temperature to drop at night, resulting in increased dissolved oxygen concentration and improved effluent wastewater quality. However, the impact of natural temperature variation on wastewater treatment systems and the energy-saving potential has yet to be fully recognized. Here, we conducted a comprehensive study, using a full-scale oxic-hydrolytic and denitrification-oxic (OHO) coking wastewater treatment process as a case and developed a dynamic aeration model integrating thermodynamics and kinetics to elucidate the energy-saving mechanisms of wastewater treatment systems in response to diurnal temperature variations. Our case study results indicate that natural diurnal temperature variations can cut the energy consumption of 660,980 kWh annually (up to 30%) for the aeration unit in the OHO system. Wastewater treatment facilities located in regions with significant environmental temperature variation stand to benefit more from this energy-saving mechanism. Methods such as flow dynamic control, load shifting, and process unit editing can be fitted into the new or retrofitted wastewater treatment engineering.


Assuntos
Temperatura , Eliminação de Resíduos Líquidos , Águas Residuárias , Águas Residuárias/química , Coque , Purificação da Água
4.
Lancet Digit Health ; 6(9): e605-e613, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39033067

RESUMO

BACKGROUND: Computer-aided detection (CAD) can help identify people with active tuberculosis left undetected. However, few studies have compared the performance of commercially available CAD products for screening in high tuberculosis and high HIV settings, and there is poor understanding of threshold selection across products in different populations. We aimed to compare CAD products' performance, with further analyses on subgroup performance and threshold selection. METHODS: We evaluated 12 CAD products on a case-control sample of participants from a South African tuberculosis prevalence survey. Only those with microbiological test results were eligible. The primary outcome was comparing products' accuracy using the area under the receiver operating characteristic curve (AUC) against microbiological evidence. Threshold analyses were performed based on pre-defined criteria and across all thresholds. We conducted subgroup analyses including age, gender, HIV status, previous tuberculosis history, symptoms presence, and current smoking status. FINDINGS: Of the 774 people included, 516 were bacteriologically negative and 258 were bacteriologically positive. Diverse accuracy was noted: Lunit and Nexus had AUCs near 0·9, followed by qXR, JF CXR-2, InferRead, Xvision, and ChestEye (AUCs 0·8-0·9). XrayAME, RADIFY, and TiSepX-TB had AUC under 0·8. Thresholds varied notably across these products and different versions of the same products. Certain products (Lunit, Nexus, JF CXR-2, and qXR) maintained high sensitivity (>90%) across a wide threshold range while reducing the number of individuals requiring confirmatory diagnostic testing. All products generally performed worst in older individuals, people with previous tuberculosis, and people with HIV. Variations in thresholds, sensitivity, and specificity existed across groups and settings. INTERPRETATION: Several previously unevaluated products performed similarly to those evaluated by WHO. Thresholds differed across products and demographic subgroups. The rapid emergence of products and versions necessitates a global strategy to validate new versions and software to support CAD product and threshold selections. FUNDING: Government of Canada.


Assuntos
Inteligência Artificial , Humanos , África do Sul/epidemiologia , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Prevalência , Estudos de Casos e Controles , Software , Radiografia Torácica/métodos , Diagnóstico por Computador/métodos , Tuberculose Pulmonar/diagnóstico por imagem , Tuberculose Pulmonar/epidemiologia , Tuberculose Pulmonar/diagnóstico , Adulto Jovem , Tuberculose/diagnóstico , Tuberculose/epidemiologia , Infecções por HIV/epidemiologia , Sensibilidade e Especificidade , Programas de Rastreamento/métodos
5.
Int J Biol Macromol ; 277(Pt 1): 134121, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39053821

RESUMO

To investigate the mechanism of lignin degradation during sesame roasting, structural transformations of milled wood lignin (MWL) from sesame seed hull samples roasted at 190-250 °C for 30 min were investigated. The findings revealed that, with increasing temperature, the degradation extent of carbohydrates from lignin carbohydrate complex in the fractions deepened, which reduced total sugar content (from 8.59 % to 0.45 %). Compared to that of the original sesame seed hull lignin (LSSH), the molecular weight of MWL fractions showed a tendency to decline (Mw 4377-2235 Da) with the rise of roasting temperature (210-250 °C). During roasting, lignins in the sesame seed hull underwent degradation and condensation. Due to demethoxylation, the H-type lignin proportion increased from 2.7 % to 26.1 %. Compared to G- and C-type lignin, S-type lignin was more stable. The ß-O-4 linkages decreased from 5.8 to 1.2/100 Ar due to CO bond breaking, and ß-ß linkages from 26.3 to 9.6/100 Ar decreased due to condensation of CC. As the roasting temperature increased, more chemical bonds between lignin structural units were broken, resulting in the generation of more phenolic hydroxyl groups (1.80-2.53 mmol/g). This study helps to elucidate the contribution of lignin degradation during roasting to the oxidative stability of sesame oil.


Assuntos
Temperatura Alta , Lignina , Sementes , Sesamum , Lignina/química , Sesamum/química , Sementes/química , Peso Molecular
6.
J Phys Chem A ; 128(27): 5260-5272, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38935921

RESUMO

Phosphaethyne (HCP) has been detected in circumstellar envelopes; its spectroscopic line list is helpful for modeling the relevant atmospheric opacity. We present the first comprehensive line list for HCP(X1Σ+) using robust first-principles methods. The analytical potential energy surface and dipole moment surface were constructed based on 26478 ab initio points from coupled-cluster calculations, along with the considerations of core-valence electron correlation and scalar relativistic effects. The variational nuclear motion program TROVE was used to obtain the ro-vibrational energy levels, Einstein A coefficients, and so on. The J-dependent Coriolis-decoupled Hamiltonian was adopted in the variational calculations with k ≤ 20, and the linear molecule treatment was applied to consider the l-type doubling of the bending vibration. The line list contains almost 0.45 billion transitions between 1.21 million levels with rotational excitation up to J = 200. It covers the wavenumber range of 0-9000 cm-1 (wavelengths above 1.11 µm) and is suitable for temperatures up to 3000 K. The millimeter wave spectra agree well with the experiments, and the Fermi resonance between 2v2 and v3 bands has been reproduced.

7.
Adv Sci (Weinh) ; 11(30): e2403746, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38874421

RESUMO

Extremely low-frequency (ELF) electromagnetic (EM) waves adeptly propagate in harsh cross-medium environments, overcoming rapid decay that hinders high-frequency counterparts. Traditional antennas, however, encounter challenges concerning size, efficiency, and power. Here, drawing inspiration from nature, we present a groundbreaking piezo-actuated, bionic flapping-wing magnetic-dipole resonator (BFW-MDR), operating in the electro-mechano-magnetic coupling mechanism, designed for efficient ELF EM wave transmission. The unique rigid-flexible hybrid flapping-wing structure magnifies rotation angles of anti-phase magnetic dipoles by tenfold, leading to constructive superposition of emitted magnetic fields. Consequently, the BFW-MDR exhibits a remarkable quality factor of 288 and an enhanced magnetic field emission of 514 fT at 100 meters with only 6.9 mW power consumption, surpassing traditional coil antennas by three orders of magnitude. The communication rate is doubled by the ASK+PSK modulation method. Its robust performance in cross-medium communication, even amidst various interferences, underscores its potential as a highly efficient antenna for underwater and underground applications.

8.
Inorg Chem ; 63(27): 12582-12592, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38917407

RESUMO

The InP-based quantum dots (QDs) have attracted much attention in the field of photocatalytic H2 evolution. However, a shell should be used for InP-based photocatalytic systems to passivate the numerous surface defects. Different from the traditional InP-based core/shell QDs with Type-I or Type-II band alignment, herein, the "reverse Type-II" core/shell QDs in which both the conduction and valence bands of shell materials are more negative than those of core materials have been well-designed by regulating the ratio of Cd/Zn of the alloyed ZnxCd1-xS shell. The reverse Type-II band alignment would realize the spatial separation of photogenerated carriers. More importantly, the photogenerated holes tend to rest on the shell in the reverse Type-II QDs, which facilitate hole transfer to the surface, the rate-determining step for solar H2 evolution using QDs. Therefore, the obtained InP/Zn0.25Cd0.75S core/shell QDs exhibit superior photocatalytic activity and stability under visible light irradiation. The rate of solar H2 evolution reaches 376.19 µmol h-1 mg-1 at the initial 46 h, with a turnover number of ∼2,157,000 per QD within 70 h irradiation.

9.
Phys Chem Chem Phys ; 26(24): 16998-17010, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38835203

RESUMO

An ab initio study of the rovibronic spectra for the cyano radical (CN) based on a diabatic representation is presented. This work considers 17 electronic states, 59 dipole moment curves, 88 spin-orbit coupling curves, and 30 electronic angular momentum coupling curves, which are obtained using the internally contracted multireference configuration interaction method including the Davidson correction (icMRCI + Q) with the aug-cc-pwCV5Z-DK basis set. The diabatic transformations are performed based on a property-based diabatization method to remove the avoided crossings for the D2Π-H2Π and b4Π-24Π pairs. Ab initio potential energy curves of the X2Σ+, B2Σ+, E2Σ+, A2Π, D2Π, H2Π, F2Δ and J2Δ electronic states are shifted to match the experimental electronic excitation energies and the equilibrium internuclear distances. The coupled nuclear motion Schrödinger equations are then solved to obtain the rovibronic spectra of CN for wavenumbers from 0 to 80 000 cm-1. At wavenumbers of 0-30 000 cm-1, our absorption cross sections agree well with available theoretical data. For wavenumbers above 30 000 cm-1, our cross sections are larger than previous data in view of the fact that the transitions involving high-lying electronic states are considered. This work provides an overall prediction of the rovibronic spectrum of CN. Our results are suitable for temperatures below 8000 K and could be useful for the investigations of planetary exploration.

10.
Phys Chem Chem Phys ; 26(22): 15957-15967, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38717797

RESUMO

The PNO molecule is an important species found in the interstellar medium, and its spectroscopic information is helpful for its detection. We present the first line list of PNO (X1Σ+) using robust first-principles methods. The analytical potential energy surface and the dipole moment surface were constructed based on 11 942 ab initio points. The variational nuclear motion calculation was implemented in TROVE to obtain the rovibrational energy levels, Einstein A coefficients and other parameters. The J-dependent Coriolis-decoupled Hamiltonian was adopted with k ≤ 15, and the l-type doubling was considered for the bending vibration of the linear molecule. The line list contained almost 5.87 billion transitions between 3.61 million levels with rotational excitation up to J = 200 and was used to generate the PNO spectrum below 3000 K in the wavenumber range from 0 to 6000 cm-1. The millimetre wave spectrum agrees well with available experimental benchmarks. The Fermi resonance effects in the PNO spectrum are universal and complex, resulting in significant intensity increment of the related weak transition. This line list may be helpful for the spectroscopic characterization and possible astronomical detection of PNO, especially in high-temperature environments.

11.
J Hazard Mater ; 472: 134540, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38733787

RESUMO

Cyanide is a typical toxic reducing agent prevailing in wastewater with a well-defined chemical mechanism, whereas its exploitation as an electron donor by microorganisms is currently understudied. Given that conventional denitrification requires additional electron donors, the cyanide and nitrogen can be eliminated simultaneously if the reducing HCN/CN- and its complexes are used as inorganic electron donors. Hence, this paper proposes anaerobic cyanides oxidation for nitrite reduction, whereby the biological toxicity and activity of cyanides are modulated by bimetallics. Performance tests illustrated that low toxicity equivalents of iron-copper composite cyanides provided higher denitrification loads with the release of cyanide ions and electrons from the complex structure by the bimetal. Both isotopic labeling and Density Functional Theory (DFT) demonstrated that CN--N supplied electrons for nitrite reduction. The superposition of chemical processes reduces the biotoxicity and enhances the biological activity of cyanides in the CN-/Fe3+/Cu2+/NO2- coexistence system, including complex detoxification of CN- by Fe3+, CN- release by Cu2+ from [Fe(CN)6]3-, and NO release by nitrite substitution of -CN groups. Cyanide is the smallest structural unit of C/N-containing compounds and serves as a probe to extend the electron-donating principle of anaerobic cyanides oxidation to more electron-donor microbial utilization.


Assuntos
Cobre , Cianetos , Ferro , Nitritos , Oxirredução , Cianetos/toxicidade , Cianetos/química , Nitritos/química , Nitritos/toxicidade , Cobre/química , Cobre/toxicidade , Anaerobiose , Ferro/química , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/química , Águas Residuárias/química , Águas Residuárias/toxicidade , Desnitrificação/efeitos dos fármacos
12.
Phys Chem Chem Phys ; 26(21): 15569-15575, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38757604

RESUMO

Iminosilylene (HNSi) has been observed in the laboratory and is expected to occur in the envelopes of carbon-rich stars. However, the lack of spectroscopic information for HNSi has hampered its further astrophysical detection. Using robust ab initio methods, we present the first and comprehensive molecular line list for HNSi (X 1Σ+). The new line list contains almost 3.36 billion transitions between 1.57 million levels with rotational excitation up to J = 160. It is suitable for temperatures up to 3000 K and covers the wavenumber range of 0-9000 cm-1 (wavelengths λ > 1.11 µm). This new line list can be helpful for the future spectroscopic characterization and molecular detection of HNSi in the laboratory and interstellar space.

13.
Water Res ; 257: 121741, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38744061

RESUMO

Biological treatment is commonly used in coking wastewater (CWW) treatment. Prokaryotic microbial communities in CWW treatment have been comprehensively studied. However, viruses, as the critical microorganisms affecting microbial processes and thus engineering parameters, still remain poorly understood in CWW treatment context. Employing viromics sequencing, the composition and function of the viral community in CWW treatment were discovered, revealing novel viral communities and key auxiliary metabolic functions. Caudovirales appeared to be the predominant viral order in the oxic-hydrolytic-oxic (OHO) CWW treatment combination, showing relative abundances of 62.47 %, 56.64 % and 92.20 % in bioreactors O1, H and O2, respectively. At the family level, Myoviridae, Podoviridae and Siphoviridae mainly prevailed in bioreactors O1 and H while Phycodnaviridae dominated in O2. A total of 56.23-92.24% of novel viral contigs defied family-level characterization in this distinct CWW habitat. The virus-host prediction results revealed most viruses infecting the specific functional taxa Pseudomonas, Acidovorax and Thauera in the entire OHO combination, demonstrating the viruses affecting bacterial physiology and pollutants removal from CWW. Viral auxiliary metabolic genes (AMGs) were screened, revealing their involvement in the metabolism of contaminants and toxicity tolerance. In the bioreactor O1, AMGs were enriched in detoxification and phosphorus ingestion, where glutathione S-transferase (GSTs) and beta-ketoadipyl CoA thiolase (fadA) participated in biodegradation of polycyclic aromatic hydrocarbons and phenols, respectively. In the bioreactors H and O2, the AMGs focused on cell division and epicyte formation of the hosts, where GDPmannose 4,6-dehydratase (gmd) related to lipopolysaccharides biosynthesis was considered to play an important role in the growth of nitrifiers. The diversities of viruses and AMGs decreased along the CWW treatment process, pointing to a reinforced virus-host adaptive strategy in stressful operation environments. In this study, the symbiotic virus-bacteria interaction patterns were proposed with a theoretical basis for promoting CWW biological treatment efficiency. The findings filled the gaps in the virus-bacteria interactions at the full-scale CWW treatment and provided great value for understanding the mechanism of biological toxicity and sludge activity in industrial wastewater treatment.


Assuntos
Águas Residuárias , Águas Residuárias/virologia , Reatores Biológicos , Bactérias/metabolismo , Eliminação de Resíduos Líquidos/métodos , Coque , Vírus , Simbiose
14.
Phys Chem Chem Phys ; 26(16): 12838-12843, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38623625

RESUMO

Hydroboron monoxide (HBO) is expected to occur in envelopes of the asymptotic giant branch (AGB), but a lack of spectroscopic data is hampering its possible detection. Using the state-of-the-art ab initio method, we present the first, comprehensive molecular line list for HBO which is suitable for temperatures up to T = 3000 K. This new line list covers the wavenumber range of 0-9000 cm-1 (wavelengths of λ ≥ 1.11 µm), and it contains almost 75 million transitions between 435 631 energy levels with rotational excitation up to J = 120. The new line list of HBO can facilitate its future molecular detection in the laboratory and interstellar space.

15.
BMC Plant Biol ; 24(1): 333, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664694

RESUMO

BACKGROUND: The circadian clock, also known as the circadian rhythm, is responsible for predicting daily and seasonal changes in the environment, and adjusting various physiological and developmental processes to the appropriate times during plant growth and development. The circadian clock controls the expression of the Lhcb gene, which encodes the chlorophyll a/b binding protein. However, the roles of the Lhcb gene in tea plant remain unclear. RESULTS: In this study, a total of 16 CsLhcb genes were identified based on the tea plant genome, which were distributed on 8 chromosomes of the tea plant. The promoter regions of CsLhcb genes have a variety of cis-acting elements including hormonal, abiotic stress responses and light response elements. The CsLhcb family genes are involved in the light response process in tea plant. The photosynthetic parameter of tea leaves showed rhythmic changes during the two photoperiod periods (48 h). Stomata are basically open during the day and closed at night. Real-time quantitative PCR results showed that most of the CsLhcb family genes were highly expressed during the day, but were less expressed at night. CONCLUSIONS: Results indicated that CsLhcb genes were involved in the circadian clock process of tea plant, it also provided potential references for further understanding of the function of CsLhcb gene family in tea plant.


Assuntos
Camellia sinensis , Ritmo Circadiano , Fotossíntese , Fotossíntese/genética , Camellia sinensis/genética , Camellia sinensis/fisiologia , Ritmo Circadiano/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Genes de Plantas , Família Multigênica , Proteínas de Ligação à Clorofila/genética , Proteínas de Ligação à Clorofila/metabolismo , Fotoperíodo
16.
Zoolog Sci ; 41(2): 210-215, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38587916

RESUMO

Protocobitis species are typical cave-dwelling fish, exhibiting distinctive morphological adaptations such as colorless body, lack of eyes, and reduced scales and ribs in response to their extreme cave habitats. Distinct from the recorded species, P. anteroventris, P. polylepis, and P. typhlops, a new species, Protocobitis longicostatus sp. nov., is described from Guangxi Zhuang Autonomous Region, China. Protocobitis longicostatus sp. nov. can easily be distinguished from all known congeners by the following characteristics: whole body covered by scales except head, 12 branched caudal fin rays, and long ribs. These species face threats from habitat degradation, hydrological changes, and environmental pollution. Thus, the conservation of cavefish in China has become an urgent issue.


Assuntos
Cipriniformes , Animais , Cipriniformes/anatomia & histologia , China , Cavernas , Olho , Ecossistema
17.
Sci Total Environ ; 930: 172511, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38641106

RESUMO

The co-occurrence of nanoplastics (NPs) and antibiotics in the environment is a growing concern for ecological safety. As NPs age in natural environments, their surface properties and morphology may change, potentially affecting their interactions with co-contaminants such as antibiotics. It is crucial to understand the effect of aging on NPs adsorption of antibiotics, but detailed studies on this topic are still scarce. The study utilized the photo-Fenton-like reaction to hasten the aging of polystyrene nanoplastics (PS-NPs). The impact of aging on the adsorption behavior of norfloxacin (NOR) was then systematically examined. The results showed a time-dependent rise in surface oxygen content and functional groups in aged PS-NPs. These modifications led to noticeable physical changes, including increased surface roughness, decreased particle size, and improved specific surface area. The physicochemical changes significantly increased the adsorption capacity of aged PS-NPs for norfloxacin. Aged PS-NPs showed 5.03 times higher adsorption compared to virgin PS-NPs. The adsorption mechanism analysis revealed that in addition to the electrostatic interactions, van der Waals force, hydrogen bonding, π-π* interactions and hydrophobic interactions observed with virgin PS-NPs, aged PS-NPs played a significant role in polar interactions and pore-filling mechanisms. The study highlights the potential for aging to worsen antibiotic risk in contaminated environments. This study not only enhances the comprehension of the environmental behavior of aged NPs but also provides a valuable basis for developing risk management strategies for contaminated areas.


Assuntos
Norfloxacino , Poliestirenos , Norfloxacino/química , Adsorção , Poliestirenos/química , Antibacterianos/química , Nanopartículas/química , Poluentes Químicos da Água/química , Processos Fotoquímicos , Modelos Químicos
18.
Zhongguo Zhong Yao Za Zhi ; 49(6): 1611-1620, 2024 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-38621946

RESUMO

This study investigated the protective effect of tanshinone Ⅱ_A(TSⅡ_A) on the liver in the rat model of non-alcoholic fatty liver disease(NAFLD) and the mechanism of TSⅡ_A in regulating ferroptosis via the nuclear factor E2-related factor 2(Nrf2) signaling pathway. The rat model of NAFLD was established with a high-fat diet for 12 weeks. The successfully modeled rats were assigned into model group, low-and high-dose TSⅡ_A groups, and inhibitor group, and normal control group was set. Enzyme-linked immunosorbent assay was employed to determine the content of superoxide dismutase(SOD) and malondialdehyde(MDA) in the serum of rats in each group. A biochemical analyzer was used to measure the content of aspartate aminotransferase(AST), alaninl aminotransferase(ALT), total cholesterol(TC), and triglycerides(TG). Hematoxylin-eosin(HE) staining was used to detect pathological damage in liver tissue. Terminal-deoxynucleoitidyl transferase-mediated nick end labeling(TUNEL) was employed to examine the apoptosis of the liver tissue. Oil red O staining, MitoSOX staining, and Prussian blue staining were conducted to reveal lipid deposition, the content of reactive oxygen species(ROS), and iron deposition in liver tissue. Western blot was employed to determine the expression of Nrf2, heme oxygenase-1(HO-1), glutathione peroxidase 4(GPX4), ferroptosis suppressor protein 1(FSP1), B cell lymphoma-2(Bcl-2), and Bcl-2 associated X protein(Bax) in the liver tissue. The result showed that TSⅡ_A significantly reduced the content of MDA, AST, ALT, TC, and TG in the serum, increased the activity of SOD, decreased the apoptosis rate, lipid deposition, ROS, and iron deposition in the liver tissue, up-regulated the expression of Nrf2, HO-1, FSP1, GPX, and Bcl-2, and inhibited the expression of Bax in the liver tissue of NAFLD rats. However, ML385 partially reversed the protective effect of TSⅡ_A on the liver tissue. In conclusion, TSⅡ_A could inhibit ferroptosis in the hepatocytes and decrease the ROS and lipid accumulation in the liver tissue of NAFLD rats by activating the Nrf2 signaling pathway.


Assuntos
Abietanos , Ferroptose , Hepatopatia Gordurosa não Alcoólica , Ratos , Animais , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Proteína X Associada a bcl-2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fígado , Transdução de Sinais , Triglicerídeos/metabolismo , Superóxido Dismutase/metabolismo , Ferro/metabolismo
19.
Environ Res ; 251(Pt 2): 118725, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38518915

RESUMO

To achieve rapid enrichment of the targeted hydrogen-producing bacterial population and reconstruction of the microbial community in the biological hydrogen-producing reactor, the activated sludge underwent multiple pretreatments using micro-aeration, alkaline treatment, and heat treatment. The activated sludge obtained from the multiple pretreatments was inoculated into the continuous stirred tank reactor (CSTR) for continuous operations. The community structure alteration and hydrogen-producing capability of the activated sludge were analyzed throughout the operation of the reactor. We found that the primary phyla in the activated sludge population shifted to Proteobacteria, Firmicutes, and Bacteroidetes, which collectively accounted for 96.69% after undergoing several pretreatments. This suggests that the multiple pretreatments facilitated in achieving the selective enrichment of the fermentation hydrogen-producing microorganisms in the activated sludge. The CSTR start-up and continuous operation of the biological hydrogen production reactor resulted in the reactor entering a highly efficient hydrogen production stage at influent COD concentrations of 4000 mg/L and 5000 mg/L, with the highest hydrogen production rate reaching 8.19 L/d and 9.33 L/d, respectively. The main genus present during the efficient hydrogen production stage in the reactor was Ethanoligenens, accounting for up to 33% of the total population. Ethanoligenens exhibited autoaggregation capabilities and a superior capacity for hydrogen production, leading to its prevalence in the reactor and contribution to efficient hydrogen production. During high-efficiency hydrogen production, flora associated with hydrogen production exhibited up to 46.95% total relative abundance. In addition, redundancy analysis (RDA) indicated that effluent pH and COD influenced the distribution of the primary hydrogen-producing bacteria, including Ethanoligenens, Raoultella, and Pectinatus, as well as other low abundant hydrogen-producing bacteria in the activated sludge. The data indicates that the multiple pretreatments and reactor's operation has successfully enriched the hydrogen-producing genera and changed the community structure of microbial hydrogen production.


Assuntos
Reatores Biológicos , Hidrogênio , Esgotos , Hidrogênio/metabolismo , Reatores Biológicos/microbiologia , Esgotos/microbiologia , Bactérias/metabolismo , Bactérias/genética , Eliminação de Resíduos Líquidos/métodos , Fermentação , Microbiota
20.
J Geriatr Cardiol ; 21(2): 219-231, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38544498

RESUMO

BACKGROUND: Myocardial infarction (MI) is a critical cardiovascular event with multifaceted etiology, involving several genetic and environmental factors. It is essential to understand the function of plasma metabolites in the development of MI and unravel its complex pathogenesis. METHODS: This study employed a bidirectional Mendelian randomization (MR) approach to investigate the causal relationships between plasma metabolites and MI risk. We used genetic instruments as proxies for plasma metabolites and MI and conducted MR analyses in both directions to assess the impact of metabolites on MI risk and vice versa. In addition, the large-scale genome-wide association studies datasets was used to identify genetic variants associated with plasma metabolite (1400 metabolites) and MI (20,917 individuals with MI and 440,906 individuals without MI) susceptibility. Inverse variance weighted was the primary method for estimating causal effects. MR estimates are expressed as beta coefficients or odds ratio (OR) with 95% CI. RESULTS: We identified 14 plasma metabolites associated with the occurrence of MI (P < 0.05), among which 8 plasma metabolites [propionylglycine levels (OR = 0.922, 95% CI: 0.881-0.965, P < 0.001), gamma-glutamylglycine levels (OR = 0.903, 95% CI: 0.861-0.948, P < 0.001), hexadecanedioate (C16-DC) levels (OR = 0.941, 95% CI: 0.911-0.973, P < 0.001), pentose acid levels (OR = 0.923, 95% CI: 0.877-0.972, P = 0.002), X-24546 levels (OR = 0.936, 95% CI: 0.902-0.971, P < 0.001), glycine levels (OR = 0.936, 95% CI: 0.909-0.964, P < 0.001), glycine to serine ratio (OR = 0.930, 95% CI: 0.888-0.974, P = 0.002), and mannose to trans-4-hydroxyproline ratio (OR = 0.912, 95% CI: 0.869-0.958, P < 0.001)] were correlated with a decreased risk of MI, whereas the remaining 6 plasma metabolites [1-palmitoyl-2-arachidonoyl-GPE (16:0/20:4) levels (OR = 1.051, 95% CI: 1.018-1.084, P = 0.002), behenoyl dihydrosphingomyelin (d18:0/22:0) levels (OR = 1.076, 95% CI: 1.027-1.128, P = 0.002), 1-stearoyl-2-docosahexaenoyl-GPE (18:0/22:6) levels (OR = 1.067, 95% CI: 1.027-1.109, P = 0.001), alpha-ketobutyrate levels (OR = 1.108, 95% CI: 1.041-1.180, P = 0.001), 5-acetylamino-6-formylamino-3-methyluracil levels (OR = 1.047, 95% CI: 1.019-1.076, P < 0.001), and N-acetylputrescine to (N (1) + N (8))-acetylspermidine ratio (OR = 1.045, 95% CI: 1.018-1.073, P < 0.001)] were associated with an increased risk of MI. Furthermore, we also observed that the mentioned relationships were unaffected by horizontal pleiotropy (P > 0.05). On the contrary, MI did not lead to significant alterations in the levels of the aforementioned 14 plasma metabolites (P > 0.05 for each comparison). CONCLUSIONS: Our bidirectional MR study identified 14 plasma metabolites associated with the occurrence of MI, among which 13 plasma metabolites have not been reported previously. These findings provide valuable insights for the early diagnosis of MI and potential therapeutic targets.

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