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1.
Nat Mater ; 23(7): 898-904, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38622325

RESUMEN

A magnon is a collective excitation of the spin structure in a magnetic insulator and can transmit spin angular momentum with negligible dissipation. This quantum of a spin wave has always been manipulated through magnetic dipoles (that is, by breaking time-reversal symmetry). Here we report the experimental observation of chiral spin transport in multiferroic BiFeO3 and its control by reversing the ferroelectric polarization (that is, by breaking spatial inversion symmetry). The ferroelectrically controlled magnons show up to 18% modulation at room temperature. The spin torque that the magnons in BiFeO3 carry can be used to efficiently switch the magnetization of adjacent magnets, with a spin-torque efficiency comparable to the spin Hall effect in heavy metals. Utilizing such controllable magnon generation and transmission in BiFeO3, an all-oxide, energy-scalable logic is demonstrated composed of spin-orbit injection, detection and magnetoelectric control. Our observations open a new chapter of multiferroic magnons and pave another path towards low-dissipation nanoelectronics.

2.
Hepatology ; 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38630500

RESUMEN

BACKGROUND AND AIMS: The complications of liver cirrhosis occur after long asymptomatic stages of progressive fibrosis and are generally diagnosed late. We aimed to develop a plasma metabolomic-based score tool to predict these events. APPROACH AND RESULTS: We enrolled 64,005 UK biobank participants with metabolomic profiles. Participants were randomly divided into the training (n=43,734) and validation cohorts (n=20,271). Liver cirrhosis complications were defined as hospitalization for liver cirrhosis or presentation with HCC. An interpretable machine-learning framework was applied to learn the metabolomic states extracted from 168 circulating metabolites in the training cohort. An integrated nomogram was developed and compared to conventional and genetic risk scores. We created 3 groups: low-risk, middle-risk, and high-risk through selected cutoffs of the nomogram. The predictive performance was validated through the area under a time-dependent receiver operating characteristic curve (time-dependent AUC), calibration curves, and decision curve analysis. The metabolomic state model could accurately predict the 10-year risk of liver cirrhosis complications in the training cohort (time-dependent AUC: 0.84 [95% CI: 0.82-0.86]), and outperform the fibrosis-4 index (time-dependent AUC difference: 0.06 [0.03-0.10]) and polygenic risk score (0.25 [0.21-0.29]). The nomogram, integrating metabolomic state, aspartate aminotransferase, platelet count, waist/hip ratio, and smoking status showed a time-dependent AUC of 0.930 at 3 years, 0.889 at 5 years, and 0.861 at 10 years in the validation cohort, respectively. The HR in the high-risk group was 43.58 (95% CI: 27.08-70.12) compared with the low-risk group. CONCLUSIONS: We developed a metabolomic state-integrated nomogram, which enables risk stratification and personalized administration of liver-related events.

3.
Nano Lett ; 24(28): 8535-8541, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-38968422

RESUMEN

Polymorph engineering involves the manipulation of material properties through controlled structural modification and is a candidate technique for creating unique two-dimensional transition metal dichalcogenide (TMDC) nanodevices. Despite its promise, polymorph engineering of magnetic TMDC monolayers has not yet been demonstrated. Here we grow FeSe2 monolayers via molecular beam epitaxy and find that they have great promise for magnetic polymorph engineering. Using scanning tunneling microscopy (STM) and spectroscopy (STS), we find that FeSe2 monolayers predominantly display a 1T' structural polymorph at 5 K. Application of voltage pulses from an STM tip causes a local, reversible transition from the 1T' phase to the 1T phase. Density functional theory calculations suggest that this single-layer structural phase transition is accompanied by a magnetic transition from an antiferromagnetic to a ferromagnetic configuration. These results open new possibilities for creating functional magnetic devices with TMDC monolayers via polymorph engineering.

4.
HIV Med ; 25(1): 60-71, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37574804

RESUMEN

OBJECTIVES: Despite the improved survival of patients with AIDS and Kaposi's sarcoma (KS), competing events are a non-negligible issue affecting the survival of such patients. In this study, we explored the prognostic factors of KS-specific and non-KS-specific mortality in patients with AIDS-related KS (AIDS-KS), accounting for competing risk. METHODS: We identified 17 103 patients with AIDS-KS aged 18-65 years between 1980 and 2016 from the Surveillance, Epidemiology, and End Results (SEER) 18 registry database. Prognostic factors for KS-specific and non-KS-specific mortality were determined by the Fine and Grey proportional subdistribution hazard model. We built competing risk nomograms and assessed their predictive performance based on the identified prognostic factors. RESULTS: In total, 12 943 (75.68%) patients died, 1965 (15.50%) of whom died from competing events. The KS-specific mortality rate was 14 835 per 100 000 person-years, and the non-KS specific mortality rate was 2719 per 100 000 person-years. Specifically, age >44 years was associated with an 11% decrease in the subdistribution hazard of KS-specific mortality compared with age <43 years but a 50% increase in the subdistribution hazard of non-KS-specific mortality. Being male was associated with a 26% increase in the subdistribution hazard of KS-specific mortality compared with being female but a 32% decrease in the subdistribution hazard of non-KS-specific mortality. Notably, being in the antiretroviral therapy (ART) era consistently showed a decrease in the subdistribution hazard of both KS-specific and non-KS-specific mortality than being in the pre-ART era. CONCLUSIONS: Competing events commonly occurred among patients with AIDS-KS, which deserves further attention to improve the prognosis of these patients.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida , Infecciones por VIH , Sarcoma de Kaposi , Humanos , Masculino , Femenino , Sarcoma de Kaposi/epidemiología , Síndrome de Inmunodeficiencia Adquirida/complicaciones , Síndrome de Inmunodeficiencia Adquirida/tratamiento farmacológico , Infecciones por VIH/complicaciones , Pronóstico
5.
J Magn Reson Imaging ; 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38426606

RESUMEN

BACKGROUND: The National Institutes of Health Stroke Scale (NIHSS) and the modified Rankin scale (mRS) scores have important shortcomings. Amide proton transfer-weighted (APTw) imaging might offer more valuable information in ischemic strokes assessment. PURPOSE: To utilize APTw, apparent diffusion coefficient (ADC), and computed tomography perfusion (CTP) for the assessment of clinical symptom severity and 90-day prognosis in patients diagnosed with ischemic stroke. STUDY TYPE: Prospective. SUBJECTS: 61 patients (mean age 63.2 ± 9.7 years; 46 males, 15 females) with ischemic strokes were included in the study. FIELD STRENGTH/SEQUENCE: 3T/turbo spin echo (TSE) T1 -weighted imaging, T2 -weighted imaging, T2 -fluid attenuated inversion recovery (T2 -FLAIR), diffusion-weighted imaging (DWI), and single-shot TSE APTw imaging. ASSESSMENT: APTw, ADC, and CTP were used to compare patient subgroups and construct a prognostic nomogram model. STATISTICAL TESTS: Kolmogorov-Smirnov test, t-test, Mann-Whitney U test, chi-square test, Pearson correlation analysis, multivariate logistic regression analysis, decision curve analysis (DCA), receiver operating characteristic curves (ROCs). The significance threshold was set at P < 0.05. RESULTS: Correlation analysis revealed that APTw and NIHSS exhibit the highest correlation (r = -0.634, 95% confidence interval [CI] -0.418 to -0.782), surpassing that of ADC and lesion size. Multivariable analysis revealed APTw (odds ratio [OR] 0.905, 95% CI 0.845-0.970), ADC (OR 0.745, 95% CI 0.609-0.911), and infarct core-cerebral blood volume (IC-CBV) (OR 0.547, 95% CI 0.310-0.964) as potential risk factors associated with a poor prognosis. The nomogram model demonstrated the highest predictive efficacy, with an area under the curve (AUC) of 0.960 (95% CI 0.911-0.988), exceeding that of APTw, ADC, and IC-CBV individually. DATA CONCLUSION: The APTw technique holds potential value in categorizing and managing patients with ischemic stroke, offering guidance for the implementation of clinical treatment strategies. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY: Stage 2.

6.
J Sci Food Agric ; 104(10): 5647-5659, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38318758

RESUMEN

The rapid growth of organic solid waste has recently exacerbated environmental pollution problems, and its improper treatment has led to the loss of a large number of biomass resources. Here, we expound the advantages of microbial agents composting compared with conventional organic solid waste treatment technology, and review the important role of microbial agents composting in organic solid waste composting from the aspects of screening and identification, optimization of conditions, mechanism of action, combination with other technologies and ultra-high-temperature and ultra-low-temperature microbial composting. We discuss the value of microorganisms with different growth conditions in organic solid waste composting, and put forward a seasonal multi-temperature composite microbial composting technology. Provide new ideas for the all-round treatment of microbial agents in organic solid waste in the future. © 2024 Society of Chemical Industry.


Asunto(s)
Bacterias , Compostaje , Eliminación de Residuos , Residuos Sólidos , Compostaje/métodos , Residuos Sólidos/análisis , Eliminación de Residuos/métodos , Bacterias/metabolismo , Bacterias/aislamiento & purificación , Bacterias/clasificación , Bacterias/crecimiento & desarrollo , Microbiología del Suelo , Hongos/metabolismo , Hongos/crecimiento & desarrollo , Hongos/aislamiento & purificación , Temperatura , Suelo/química
7.
Small ; 19(23): e2206948, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36879416

RESUMEN

With advances in cancer biology and an ever-deepening understanding of molecular virology, oncolytic virus (OV)-driven therapies have developed rapidly and become a promising alternative to traditional cancer therapies. In recent years, satisfactory results for oncolytic virus therapy (OVT) are achieved at both the cellular and organismal levels, and efforts are being increasingly directed toward clinical trials. Unfortunately, OVT remains ineffective in these trials, especially when performed using only a single OV reagent. In contrast, integrated approaches, such as using immunotherapy, chemotherapy, or radiotherapy, alongside OVT have demonstrated considerable efficacy. The challenges of OVT in clinical efficacy include the restricted scope of intratumoral injections and poor targeting of intravenous administration. Further optimization of OVT delivery is needed before OVs become a viable therapy for tumor treatment. In this review, the development process and antitumor mechanisms of OVs are introduced. The advances in OVT delivery routes to provide perspectives and directions for the improvement of OVT delivery are highlighted. This review also discusses the advantages and limitations of OVT monotherapy and combination therapy through the lens of recent clinical trials and aims to chart a course toward safer and more effective OVT strategies.


Asunto(s)
Neoplasias , Viroterapia Oncolítica , Virus Oncolíticos , Humanos , Viroterapia Oncolítica/métodos , Neoplasias/terapia , Inmunoterapia , Terapia Combinada
8.
Nat Mater ; 21(7): 748-753, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35710632

RESUMEN

One-dimensional electron systems exhibit fundamentally different properties than higher-dimensional systems. For example, electron-electron interactions in one-dimensional electron systems have been predicted to induce Tomonaga-Luttinger liquid behaviour. Naturally occurring grain boundaries in single-layer transition metal dichalcogenides exhibit one-dimensional conducting channels that have been proposed to host Tomonaga-Luttinger liquids, but charge density wave physics has also been suggested to explain their behaviour. Clear identification of the electronic ground state of this system has been hampered by an inability to electrostatically gate such boundaries and tune their charge carrier concentration. Here we present a scanning tunnelling microscopy and spectroscopy study of gate-tunable mirror twin boundaries in single-layer 1H-MoSe2 devices. Gating enables scanning tunnelling microscopy and spectroscopy for different mirror twin boundary electron densities, thus allowing precise characterization of electron-electron interaction effects. Visualization of the resulting mirror twin boundary electronic structure allows unambiguous identification of collective density wave excitations having two velocities, in quantitative agreement with the spin-charge separation predicted by finite-length Tomonaga-Luttinger liquid theory.

9.
Environ Res ; 237(Pt 2): 116976, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37625535

RESUMEN

Soil, as a heterogeneous body, is composed of different-sized aggregates. There is limited data available on the potential role of microplastics (MPs) in microbial properties at the soil aggregate level. In this study, changes in microbial construction and diversity in farmland bulk soil and aggregates induced by polyethylene MPs (PE-MPs) were investigated at a dose of 0.5% (w/w) through 16s rDNA sequencing and enzyme activity measurements of different particle size aggregates in incubated soil. The presence of low-dose PE-MPs increased the proportion of >1 mm soil aggregates fraction, and decreased soil available nitrogen and available phosphorus in bulk soils. Furthermore, low-dose PE-MPs increased bacterial richness and diversity in 1-0.5 and < 0.25 mm fractions and decreased operational taxonomic unit, abundance-based coverage estimator, and Chao1 indices in bulk soil and >1 mm fractions. The levels of predicted functional genes taking part in the biodegradation and metabolism of exogenous substances also increased. At the phylum level, PE-MPs changed the proportion of Proteobacteria and Actinobacteria. The variations in soil aggregate properties were significantly correlated with the bacterial communities' composition and diversity. This study deepens our perception of the soil microenvironment, microbial community composition, and diversity in response to PE-MPs.

10.
Ecotoxicol Environ Saf ; 259: 115037, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37210996

RESUMEN

Peri-urban vegetable field plays an essential role in providing vegetables for local residents. Because of its particularity, it is affected by both industrial and agricultural activities which have led to the accumulations of heavy metal in soil. So far, information on heavy metal pollution status, spatial features, and human health risks in peri-urban vegetable areas across China is still scarce. To fill this gap, we systematically compiled soil and vegetable data collected from 123 articles published between 2010 and 2022 at a national level. The pollution status of heavy metals (i.e., cadmium (Cd), mercury (Hg), arsenic (As), lead (Pb), chromium (Cr), copper (Cu), nickel (Ni), and zinc (Zn)) in peri-urban vegetable soils and vegetables were investigated. To evaluate the levels of heavy metal pollution in soil and human health risks, the geoaccumulation index (Igeo) and target hazard quotient (HQ) were calculated. The results showed that mean concentrations of Cd, Hg, As, Pb, Cr, Cu, Ni, and Zn in peri-urban vegetable soils were 0.50, 0.53, 12.03, 41.97, 55.56, 37.69, 28.55, and 75.38 mg kg-1, respectively. The main pollutants in peri-urban vegetable soil were Cd and Hg, and 85.25% and 92.86% of the soil samples had Igeo > 1, respectively. The mean Igeo values of this regions followed the order of northwest > central > south > north > east > southwest > northeast for Cd and northeast > northwest > north > southwest > east > central > south for Hg. The mean Cd, Hg, As, Pb, Cr, Cu, Ni, and Zn concentrations in vegetables were 0.30, 0.26, 0.37, 0.54, 1.17, 6.17, 1.96, and 18.56 mg kg-1, respectively. Approximately 87.01% (Cd), 71.43% (Hg), 20% (As), 65.15% (Pb), 27.08% (Cr) of the vegetable samples exceeded the safety requirement values. The vegetables grown in central, northwest, and northern China accumulated much more heavy metals than those grown in other regions. As the HQ values for adults, 53.25% (Cd), 71.43% (Hg), 84.00% (As), and 58.33% (Cr) of the sampled vegetables were higher than 1. For children, the HQ values were higher than 1 for 66.23% (Cd), 73.81% (Hg), 86.00% (As), and 87.50% (Cr) of the sampled vegetables. The findings of this study demonstrate that the situation of heavy metal pollution in peri-urban vegetable areas across China are not optimistic and residents who consume the vegetables are at high risk of health issues. To ensure soil quality and human health, strategies should be taken to guide vegetable production and remedy soil pollution in peri-urban areas with the rapidly urbanizing China.


Asunto(s)
Arsénico , Mercurio , Metales Pesados , Contaminantes del Suelo , Adulto , Niño , Humanos , Verduras , Suelo , Cadmio , Plomo , Contaminantes del Suelo/análisis , Metales Pesados/análisis , Zinc , Cromo , Níquel , China , Medición de Riesgo , Monitoreo del Ambiente/métodos
11.
Phytother Res ; 35(10): 5720-5733, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34411362

RESUMEN

Tumor resistance is the main cause of treatment failure and is associated with many tumor factors. Jaridon 6, a new diterpene extracted from Rabdosia rubescens (Hemsl.) Hara, which has been previously extracted by our research team, has been tested having more obvious advantages in resistant tumor cells. However, its mechanism is unclear. In this study, we studied the effect and the specific mechanism of Jaridon 6 in resistant gastric cancer cells. Cytotoxicity test, colony test, western blotting, and nude test verified the anti-drug resistance ability of Jaridon 6 in the MGC803/PTX and MGC803/5-Fu cells. Jaridon 6 has shown obvious inhibitory effects in the sirtuin 1 (SIRT1) enzyme test. Transmission electron microscopy and immunofluorescence tests further proved the autophagic action of Jaridon 6. Jaridon 6 could inhibit the proliferation of the resistant gastric cancer cell in vivo and in vitro. Jaridon 6 inhibited SIRT1 enzyme and induced autophagy by inhibiting the phosphoinositide 3-kinase/protein kinase B (PI3K/AKT) pathway. Thus, it may be considered for treating gastric cancer resistance by individual or combined administration, as an SIRT1 inhibitor and autophagy inducer.


Asunto(s)
Diterpenos de Tipo Kaurano , Isodon , Neoplasias Gástricas , Apoptosis , Autofagia , Línea Celular Tumoral , Proliferación Celular , Humanos , Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Sirtuina 1 , Neoplasias Gástricas/tratamiento farmacológico
12.
J Sci Food Agric ; 100(13): 4766-4775, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32458515

RESUMEN

BACKGROUND: Peel color is an economically relevant trait that influences the appearance and quality of red pear, whose red color is due to anthocyanin accumulation. Prohydrojasmon (PDJ), which has similar effects to endogenous jasmonates, was developed as a commercial bioregulator, particularly to improve fruits coloring. However, little information is available about the effect of PDJ on pears. This study investigated the effects of preharvest PDJ treatments on color development, phenolic compounds accumulation, and related gene expression in the red pear cultivar 'Nanhong'. The treatments were performed during the pre-color-change period by spraying 50 or 100 mg L-1 of PDJ on fruits. RESULTS: Preharvest PDJ treatments had a significant effect on color development, without affecting other quality parameters such as total soluble solids and fruit acidity. Liquid chromatography-mass spectrometry analysis showed that concentrations of anthocyanins and flavonols were enhanced in the peel after PDJ treatments, particularly when a concentration of 100 mg L-1 was used, whereas those of hydroxycinnamates and flavanols were decreased. After PDJ application, the transcription levels of anthocyanin biosynthesis genes PAL, CHS, CHI, ANS, F3H, and UFGT were enhanced, especially under the higher PDJ concentration tested. In addition, anthocyanin accumulation in the peels of PDJ-treated fruits was found to be positively correlated with the upregulation of the regulatory gene MYB114. CONCLUSION: Preharvest treatments with PDJ could be a useful tool to improve fruits coloring and increase phenolic content in pear. These findings also improve our understanding of the molecular mechanisms associated with PDJ-regulated anthocyanin accumulation in pear fruits.


Asunto(s)
Frutas/crecimiento & desarrollo , Fenoles/metabolismo , Reguladores del Crecimiento de las Plantas/farmacología , Proteínas de Plantas/genética , Pyrus/efectos de los fármacos , Antocianinas/biosíntesis , Color , Frutas/química , Frutas/genética , Frutas/metabolismo , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Fenoles/química , Proteínas de Plantas/metabolismo , Pyrus/genética , Pyrus/crecimiento & desarrollo , Pyrus/metabolismo
13.
Can J Microbiol ; 65(7): 510-521, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30901528

RESUMEN

Microbial communities drive geochemical cycles in soils. Relatively few studies have assessed the long-term impacts of different types of soil amendments under field conditions in long-term experiments. The response of soil microbial organisms in a Mollisol cultivated with maize for 35 years was examined. Treatments involved the use of N, P, and K fertilizers and two doses of straw residue in isolation or combined. Real-time PCR and Illumina MiSeq sequencing methods were used to characterize the microbial community. The results showed that addition of nitrogen fertilizers decreased soil pH, but this was mitigated when a high dose of straw was also incorporated. Long-term application of inorganic fertilizers was able to alter the abundance of functional soil microbial population. Application of inorganic N fertilizer resulted in distinctive changes on N-cycle microorganisms. Phosphate-solubilizing functional genes abundance was lower in plots with no phosphate fertilizer. Sequencing analysis showed that the presence or absence of N in the fertilizer mix is a key factor affecting bacterial community diversity of agricultural soil, and pH, total organic C, and total N show a high correlation with bacterial community composition. Nitrogen addition increased the N concentration in the soil, which could cause changes in the soil pH and change the soil bacterial community. Our findings proved that interaction of N fertilizer with other fertilizers can affect microbial communities.


Asunto(s)
Fertilizantes , Nitrógeno , Microbiología del Suelo , Suelo , Agricultura , Bacterias/efectos de los fármacos , Microbiota/efectos de los fármacos , Nitrógeno/farmacología , Suelo/química , Zea mays
14.
Can J Microbiol ; 64(12): 925-936, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30114373

RESUMEN

The characteristics of the rhizosphere microbial community across different cultivation years (from 1, 3, 5, 15, 20, and 50 years) in saline-alkaline paddy soils in Songnen Plain of China were investigated based on sequence variation of 16S rDNA using Illumina MiSeq sequencing. The results showed that the microbial community diversity varied across cultivation years, showing higher diversity in cultivation years >15 than in cultivation years <15. The dominant microbial community of the rhizosphere was mainly composed of Proteobacteria, Acidobacteria, Firmicutes, and Bacteroidetes. Furthermore, soil microbial diversity appeared to be affected directly by changes in soil properties corresponding to cultivated years. Diversity of Proteobacteria decreased as cultivated years increased; however, that of Acidobacteria showed the opposite direction. In addition, the soil microbial communities were clustered into two main groups: one from the sites cultivated for fewer than 15 years, and the other from the sites cultivated for more than 15 years. The abundance of nitrogen-fixing microorganisms in the soil sample was significantly higher in soils cultivated for under 15 years than in those cultivated for over 15 years (P < 0.05). Moreover, there was an obvious negative correlation between the cultivated years and Methanosarcina. Our findings on the dynamics of microbial community and its specific function in response to variable soil conditions are important for understanding and improving physical and chemical characteristics of saline-alkaline soil in Songnen Plain of China.


Asunto(s)
Bacterias/crecimiento & desarrollo , Microbiota , Rizosfera , Microbiología del Suelo
15.
Environ Pollut ; 341: 122981, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-37992952

RESUMEN

Modified hydrochar (NHC@Fe), with multiple functional groups and transition metal oxide-containing surface, was successfully synthesized by one-step hydrothermal method. The differences in its catalytic activity for peroxymonosulfate (PMS) and peroxydisulfate (PDS) activation were studied in detail. Experimental and DFT studies showed that abundant active sites, namely, transition metals and functional groups on NHC@Fe provided multiple effective pathways for the activation of persulfate (PS). The NHC@Fe/PMS and NHC@Fe/PDS systems could degrade about 80% of tetracycline hydrochloride (TC) in 120 min and were found to be better than those modified by iron or nitrogen alone. This emphasized the advantage of N-Fe co-modification in persulfate activation. Although the Fe2+/Fe3+ cycle accelerated the activation, the activation of PMS mainly relied on Fe3+, whereas that of PDS mainly relied on Fe2+. Moreover, Fe-N, pyrrolic N, pyridine N, C-O, and O-CO groups also played a key role in the activation process, but the dominant action sites were not the same. Multiple free radicals, such as SO4•-, •OH, O2•-, and 1O2 were generated in PMS and PDS activation systems. 1O2 induced non-free radical pathway was mainly involved in the degradation of TC in both activation systems, but the generation pathway of 1O2 was more direct and rapid in the PDS system. This study provides detailed DFT models of the active sites activated by PMS and PDS and discusses the activation pathways of PMS and PDS along with the similarities and differences in ROS reaction mechanisms.


Asunto(s)
Óxidos , Peróxidos , Dominio Catalítico , Hierro
16.
Biomed Pharmacother ; 177: 117063, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38968800

RESUMEN

Off-targeting toxicity and immunosuppressive tumor microenvironment still restrict the therapeutic requirement of photodynamic therapy (PDT). The development of metal ion-coordination-based nanoparticles (NPs) for cancer therapy has advantages, such as precious nanostructure and potent therapeutic effect as well as great safety. In this study, we prepared calcium ions (Ca2+)-coordination photosensitizer NPs, based on Ca2+-pyrochloric acid (PPA)-coordination as the new photosensitive nanoamplifiers, and microneedles (MNs) as the personalized apparatus, and investigated the nanoamplifiers for treating the melanoma via transdermal administration. This nanoamplifiers was synthesized via a simple coordination of Ca2+ and PPA with the addition of bovine serum albumin (BSA), and further fabricated into MNs (nanoamplifiers@MNs). Following inserted into the tumor, the released nanoamplifiers from the tips and back layer exhibited great photodynamic activity under irradiation, inducing cancer cell death. Meanwhile, Ca2+ acted as the second messenger, promoting M1 polarization of macrophages and maturation of dendritic cells (DCs), thereby enhancing the immune activation effect in the tumor microenvironment. As a result, such nanoamplifiers effectively achieved significant efficacy against malignant melanoma tumors by synergistically tumor killing and potent anti-tumor immune activation without obviously side effect. This work demonstrated the potential of MNs-mediated metal ion-coordination-based nanoamplifier as a novel photodynamic therapeutic platform for the efficient and safe treatment of cancer.


Asunto(s)
Calcio , Agujas , Fotoquimioterapia , Fármacos Fotosensibilizantes , Microambiente Tumoral , Fotoquimioterapia/métodos , Microambiente Tumoral/efectos de los fármacos , Animales , Fármacos Fotosensibilizantes/administración & dosificación , Fármacos Fotosensibilizantes/farmacología , Calcio/metabolismo , Ratones , Línea Celular Tumoral , Nanopartículas/química , Ratones Endogámicos C57BL , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/patología , Melanoma/tratamiento farmacológico , Melanoma/patología , Células Dendríticas/efectos de los fármacos , Melanoma Experimental/tratamiento farmacológico , Melanoma Experimental/patología
17.
Bioresour Technol ; 396: 130415, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38316228

RESUMEN

Microbial immobilization technology is effective in improving bioremediation efficiency and heavy metal pollution. Herein, Bacillus LD513 with hexavalent chromium (Cr(VI)) tolerance was isolated and immobilized on a novel ferrous disulfide (FeS2)/iron nitride (FeN) modified hydrochar (Fe3-SNHC) prepared from waste straws. The prepared Fe3-SNHC-based LD513 (FeLD) significantly improves Cr(VI) adsorption and reduction by 31.4 % and 15.7 %, respectively, compared to LD513 alone. Furthermore, the FeLD composite system demonstrates efficient Cr(VI) removal efficiency and good environmental adaptability under different culture conditions. Microbial metabolism and electrochemical analysis indicate that Fe3-SNHC is an ideal carrier for protecting LD513 activity, promoting extracellular polymer secretion, and reducing oxidative stress. Additionally, the carrier serves as an electron shuttle that accelerates electron transfer and promotes Cr(VI) reduction. Overall, FeLD is an environmentally friendly biocomposite that shows good promise for reducing Cr(VI) contamination in wastewater treatment.


Asunto(s)
Bacillus , Compuestos Férricos , Hierro , Sulfuros , Contaminantes Químicos del Agua , Bacillus/metabolismo , Adsorción , Electrones , Cromo/metabolismo
18.
Heliyon ; 10(8): e29502, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38660282

RESUMEN

Kaposi's sarcoma (KS) is the second most common tumor in human immunodeficiency virus (HIV) infected patients worldwide. While many miRNAs have been confirmed to be involved in KS biological processes, no relevant studies have combined miRNA and mRNA expression profiles using KS patient tissue biopsies. In this study, we performed transcriptome sequencing on tumor and normal tissues from four KS patients and identified differentially expressed mRNA and miRNA, further performed target gene prediction and enrichment analysis. 19,551 target-mRNAs were identified by predicting 106 miRNAs, with 553 overlapping with 571 significantly differentially expressed mRNAs. Enrichment analysis showed significant involvement of the Ubiquitin-mediated proteolysis pathway. Additionally, the miRNA-mRNA interaction network was established, and the topological score of Cytohubba's algorithm was calculated for comparison with three other datasets. The Mutual Clustering Coefficient (MCC) scoring ranking placed ZBTB34, NFIB, and RORA as the top three mRNAs, while hsa-miR-16-5p, hsa-miR-27a-3p, hsa-miR-340-5p, hsa-miR-182-5p, and hsa-miR-186-5p ranked as the top five miRNAs. Hsa-miR-101-3p is the only miRNA that appears both in the top 10 MCC scores and at the intersection of the other two datasets. Finally, qRT-PCR was used to validate the findings at the cellular level. In summary, the miRNA analysis results indicated that hsa-miR-101-3p could be used as a potential diagnostic or therapeutic marker in future studies. Moreover, the mRNA analysis results suggested that the histone binding pathways involved in mRNAs and ubiquitin-related biological processes were closely associated with KS and could serve as promising biomarkers for the diagnosis and treatment of this disease.

19.
J Hazard Mater ; 471: 134251, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38640669

RESUMEN

Corn planting is often associated with serious atrazine pollution and excessive corn straw amounts, causing severe threats to environmental and ecological security, as well as to green agricultural development. In this context, a Paenarthrobacter sp. KN0901 strain was applied to simultaneously remove atrazine and straw at low temperatures. The results of whole genome sequencing indicated that KN0901 encoded over nine straw biodegradation-related enzymes. In addition, 100 % and 27.3 % of atrazine and straw were simultaneously degraded by KN0901 following an incubation period of seven days at 15 ºC and 180 rpm in darkness. The KN0901 strain maintained high atrazine and straw biodegradation rates under temperature and pH ranges of 4-25 ºC and 5-9, respectively. The simultaneous atrazine and corn straw additions improved the microbial growth and biodegradation rates by increasing the functional gene expression level, cell viability, inner membrane permeability, and extracellular polymeric substance contents of KN0901. The hydroponic experiment results demonstrated the capability of the KN0901 strain to mitigate the toxicity of atrazine to soybeans in four days under the presence of corn straw. The present study provides a new perspective on the development of bioremediation approaches and their application to restore atrazine-polluted cornfields with large straw quantities, particularly in cold areas.


Asunto(s)
Atrazina , Biodegradación Ambiental , Frío , Herbicidas , Zea mays , Atrazina/toxicidad , Atrazina/metabolismo , Herbicidas/toxicidad , Herbicidas/metabolismo , Secuenciación Completa del Genoma , Genoma Bacteriano
20.
Sci Total Environ ; 917: 170541, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38290684

RESUMEN

Microplastics (MPs) can co-occur widely with heavy metals in soil. This study intended to investigate the influences of the co-exposure of polyethylene MPs (0.5 %, w/w) and cadmium (Cd) in black soil on the Cd distribution, enzyme activities, and bacterial communities in both bulk soil and different sized soil aggregates (> 1, 0.50-1, 0.25-0.50, and < 0.25 mm aggregates) after a 90-day incubation. Our results showed that the existence of MPs increased the distributions of Cd in >1 mm and < 0.25 mm soil aggregates and decreased its distributions in 0.50-1 mm and 0.25-0.50 mm soil aggregates. About 12.15 %-17.65 % and 9.03 %-11.13 % of Cd were distributed in the exchangeable and oxidizable forms in bulk soil and various sized soil aggregates after the addition of MPs which were higher than those in the only Cd-treated soil (11.17 %-14.72 % and 8.66 %-10.43 %, respectively), while opposite tendency was found for Cd in the reducible form. Urease and ß-glucosidase activities in the Cd-treated soils were 1.14-1.18 and 1.07-1.31 times higher than those in the Cd-MPs treated soils. MPs disturbed soil bacterial community at phylum level and increased the bacteria richness in bulk soil. The levels of predicted functional genes which are linked to the biodegradation and metabolism of exogenous substances and soil C and N cycles were altered by the co-exposure of Cd and MPs. The findings of this study could help deepen our knowledge about the responses of soil properties, especially microbial community, to the co-occurrence of MPs and heavy metals in soil.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Microplásticos , Cadmio/análisis , Plásticos , Suelo , Polipropilenos , Contaminantes del Suelo/análisis , Bacterias
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