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1.
Sci Total Environ ; 928: 172345, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38621537

RESUMO

Fine particulate matter (PM2.5) causes millions of premature deaths each year worldwide. Oxidative potential (OP) has been proposed as a better metric for aerosol health effects than PM2.5 mass concentration alone. In this study, we report for the first time online measurements of PM2.5 OP in wintertime Beijing and surroundings based on a dithiothreitol (DTT) assay. These measurements were combined with co-located PM chemical composition measurements to identify the main source categories of aerosol OP. In addition, we highlight the influence of two distinct pollution events on aerosol OP (spring festival celebrations including fireworks and a severe regional dust storm). Source apportionment coupled with multilinear regression revealed that primary PM and oxygenated organic aerosol (OOA) were both important sources of OP, accounting for 41 ± 12 % and 39 ± 10 % of the OPvDTT (OP normalized by the sampled air volume), respectively. The small remainder was attributed to fireworks and dust, mainly resulting from the two distinct pollution events. During the 3.5-day spring festival period, OPvDTT spiked to 4.9 nmol min-1 m-3 with slightly more contribution from OOA (42 ± 11 %) and less from primary PM (31 ± 15 %). During the dust storm, hourly-averaged PM2.5 peaked at a very high value of 548 µg m-3 due to the dominant presence of dust-laden particles (88 % of total PM2.5). In contrast, only mildly elevated OPvDTT values (up to 1.5 nmol min-1 m-3) were observed during this dust event. This observation indicates that variations in OPvDTT cannot be fully explained using PM2.5 alone; one must also consider the chemical composition of PM2.5 when studying aerosol health effects. Our study highlights the need for continued pollution control strategies to reduce primary PM emissions, and more in-depth investigations into the source origins of OOA, to minimize the health risks associated with PM exposure in Beijing.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38573076

RESUMO

An aerobic, non-motile, Gram-stain-positive bacterium, designated strain NEAU-Y5T, was isolated from a soil sample collected from Northeast Agricultural University, Heilongjiang province. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain NEAU-Y5T belonged to the genus and showed high 16S rRNA sequence similarity to Isoptericola variabilis (98.9 %), Isoptericola nanjingensis (98.9 %), Isoptericola cucumis (98.5 %), Isoptericola hypogeus (98.5 %), Isoptericola dokdonensis (98.5 %), Isoptericola jiangsuensis (98.3 %), and Isoptericola halalbus (98.1 %), followed by other members of the genus Isoptericola (<98 %), and phylogenetically clustered with I. dokdonensis and I. jiangsuensis. Strain NEAU-Y5T was found to grow at 4-40 °C (optimum, 28 °C), pH 6.0-12.0 (optimum, pH 7.0), and tolerated 0-6 % NaCl (w/v). The cell-wall peptidoglycan type was l-Lys-d-Asp. The whole-cell hydrolysates contained glucose, galactose, and ribose. The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, hydroxyphosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannoside, and glucosamine unknown phospholipid. Major fatty acids were anteiso-C15 : 0 and anteiso-C17 : 0. The predominant menaquinone was MK-9(H4). The DNA G+C content was 73.4 mol%. The digital DNA-DNA hybridization and average nucleotide identity values between strain NEAU-Y5T and the type strains of the genus Isoptericola ranged from 18.6 to 23.5 % and from 77.3 to 81.6 %, respectively. Based on morphological, physiological, chemotaxonomic, and phylogenetic data, as well as digital DNA-DNA hybridization and average nucleotide identity values, the novel strain NEAU-Y5T could be differentiated from its closest relatives. Therefore, the strain represents a novel species of the genus Isoptericola, for which the name Isoptericola luteus sp. nov. is proposed. The type strain is NEAU-Y5T (=CCTCC AA 2019087T=DSM 110637T).


Assuntos
Actinomycetales , Solo , Humanos , Filogenia , RNA Ribossômico 16S/genética , Composição de Bases , Ácidos Graxos/química , Análise de Sequência de DNA , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Bactérias , Nucleotídeos
3.
Phytomedicine ; 128: 155279, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38581801

RESUMO

BACKGROUND: Osteoarthritis (OA) is characterized by degeneration of articular cartilage, leading to joint pain and dysfunction. Gubi Zhitong formula (GBZTF), a traditional Chinese medicine formula, has been used in the clinical treatment of OA for decades, demonstrating definite efficacy. However, its mechanism of action remains unclear, hindering its further application. METHODS: The ingredients of GBZTF were analyzed and performed with liquid chromatography-mass spectrometry (LC-MS). 6 weeks old SD rats were underwent running exercise (25 m/min, 80 min, 0°) to construct OA model with cartilage wear and tear. It was estimated by Micro-CT, Gait Analysis, Histological Stain. RNA-seq technology was performed with OA Rats' cartilage, and primary chondrocytes induced by IL-1ß (mimics OA chondrocytes) were utilized to evaluated and investigated the mechanism of how GBZTF protected OA cartilage from being damaged with some functional experiments. RESULTS: A total of 1006 compounds were identified under positive and negative ion modes by LC-MS. Then, we assessed the function of GBZTF through in vitro and vivo. It was found GBZTF could significantly up-regulate OA rats' limb coordination and weight-bearing capacity, and reduce the surface and sub-chondral bone erosions of OA joints, and protect cartilage from being destroyed by inflammatory factors (iNOS, IL-6, IL-1ß, TNF- α, MMP13, ADAMTS5), and promote OA chondrocytes proliferation and increase the S phage of cell cycle. In terms of mechanism, RNA-seq analysis of cartilage tissues revealed 1,778 and 3,824 differentially expressed genes (DEGs) in model vs control group and GBZTF vs model group, respectively. The mitophagy pathway was most significantly enriched in these DEGs. Further results of subunits of OA chondrocytes confirmed that GBZTF could alleviate OA-associated inflammation and cartilage damage through modulation BCL2 interacting protein 3-like (BNIP3L)-mediated mitophagy. CONCLUSION: The therapeutic effectiveness of GBZTF on OA were first time verified in vivo and vitro through functional experiments and RNA-seq, which provides convincing evidence to support the molecular mechanisms of GBZTF as a promising therapeutic decoction for OA.

5.
Artigo em Inglês | MEDLINE | ID: mdl-38591200

RESUMO

BACKGROUND: In the domain of functional gastrointestinal disorders, Functional Dyspepsia (FD) stands out due to its widespread occurrence internationally. Historically, electroacupuncture (EA) has been employed as a therapeutic modality for FD, demonstrating notable clinical efficacy. OBJECTIVES: This research aimed to delve into the impact of EA on stress responses, minor duodenal inflammatory processes, and the integrity of the intestinal barrier within FD-affected rodent models while also elucidating the underlying mechanisms. METHODS: Thirty-six male Wistar rats were evenly distributed into three cohorts: a normal, a modeled FD, and an EA treatment group. The FD condition in the rats, barring those in the normal, was induced through a series of multifactorial procedures. For the EA cohort, the rats received electroacupuncture at the acupoints RN12 (Zhongwan) and ST36 (Zusanli) for 20 minutes daily over a span of one week. The gastric residue rate (GRR), intestinal propulsion rate (IPR), and changes in emotional state were measured in each group of rats. Additionally, serum levels of corticotropin-releasing hormone (CRH), adrenocorticotropic hormone (ACTH), and corticosterone (CORT) were detected, and the duodenal inflammatory condition and intestinal mucosal barrier status were observed through staining and fluorescence. The expression levels of Claudin-1, Junctional Adhesion Molecule 1 (JAM-1), Corticotropin-Releasing Factor (CRF), and Corticotropin-Releasing Factor Receptor 1 (CRF-R1) were also detected. RESULTS: The study demonstrated that EA had a positive effect on body weight and food intake, GRR, and IPR in FD rats. Additionally, the EA group showed a decrease in serum levels of CRH, ACTH, and CORT, as well as a decrease in the number of duodenal mast cells and tryptase content. Furthermore, the expression of tight junction proteins Claudin-1 and JAM-1 was increased in the EA group compared to the model group. EA also reduced the levels of CRF and CRF-R1 in the hypothalamus and duodenum. CONCLUSION: EA has been shown to improve the stress state of FD rats, inhibit the activation of mast cells in the duodenum, and reduce low-grade inflammatory response and damage to the intestinal mucosal barrier. It is believed that EA achieves these effects by modulating the expression of CRF and its receptors in the brain-gut interaction pathway through the CRF signaling pathway. This provides a new approach to treating FD.

6.
CNS Neurosci Ther ; 30(3): e14563, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38481068

RESUMO

BACKGROUND: Glioblastoma is the most common primary malignant brain tumor in adults. TTFields is a therapy that use intermediate-frequency and low-intensity alternating electric fields to treat tumors. For patients with ndGBM, the addition of TTFields after the concurrent chemoradiotherapy phase of the Stupp regimen can improve prognosis. However, TTFields still has the potential to further prolong the survival of ndGBM patients. AIM: By summarizing the mechanism and application status of TTFields in the treatment of ndGBM, the application prospect of TTFields in ndbm treatment is prospected. METHODS: We review the recent literature and included 76 articles to summarize the mechanism of TTfields in the treatment of ndGBM. The current clinical application status and potential health benefits of TTFields in the treatment of ndGBM are also discussed. RESULTS: TTFields can interfere with tumor cell mitosis, lead to tumor cell apoptosis and increased autophagy, hinder DNA damage repair, induce ICD, activate tumor immune microenvironment, reduce cancer cell metastasis and invasion, and increase BBB permeability. TTFields combines with chemoradiotherapy has made progress, its optimal application time is being explored and the problems that need to be considered when retaining the electrode patches for radiotherapy are further discussed. TTFields shows potential in combination with immunotherapy, antimitotic agents, and PARP inhibitors, as well as in patients with subtentorial gliomas. CONCLUSION: This review summarizes mechanisms of TTFields in the treatment of ndGBM, and describes the current clinical application of TTFields in ndGBM. Through the understanding of its principle and application status, we believe that TTFields still has the potential to further prolong the survival of ndGBM patients. Thus,research is still needed to explore new ways to combine TTFields with other therapies and optimize the use of TTFields to realize its full potential in ndGBM patients.


Assuntos
Neoplasias Encefálicas , Terapia por Estimulação Elétrica , Glioblastoma , Glioma , Adulto , Humanos , Glioblastoma/patologia , Terapia Combinada , Glioma/terapia , Terapia por Estimulação Elétrica/métodos , Prognóstico , Neoplasias Encefálicas/patologia , Microambiente Tumoral
7.
Anal Chem ; 96(8): 3373-3381, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38345945

RESUMO

While conventional ion-soft landing uses the mass-to-charge (m/z) ratio to achieve molecular selection for deposition, here we demonstrate the use of Structures for Lossless Ion Manipulation (SLIM) for mobility-based ion selection and deposition. The dynamic rerouting capabilities of SLIM were leveraged to enable the rerouting of a selected range of mobilities to a different SLIM path (rather than MS) that terminated at a deposition surface. A selected mobility range from a phosphazene ion mixture was rerouted and deposited with a current pulse (∼150 pA) resembling its mobility peak. In addition, from a mixture of tetra-alkyl ammonium (TAA) ions containing chain lengths of C5-C8, selected chains (C6, C7) were collected on a surface, reconstituted into solution-phase, and subsequently analyzed with a SLIM-qToF to obtain an IMS/MS spectrum, confirming the identity of the selected species. Further, this method was used to characterize triply charged tungsten-polyoxometalate anions, PW12O403- (WPOM). The arrival time distribution of the IMS/MS showed multiple peaks associated with the triply charged anion (PW12O403-), of which a selected ATD was deposited and imaged using TEM. Additionally, the identity of the deposited WPOM was ascertained using energy-dispersive (EDS) spectroscopy. Further, we present theory and computations that reveal ion landing energies, the ability to modulate the energies, and deposition spot sizes.

8.
Sci Total Environ ; 917: 170612, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38307269

RESUMO

Nitrated aromatic compounds (NACs) are key components of air pollution; however, due to the presence of complex mixtures of primary and secondary species, especially in urban environments, their atmospheric formation is poorly understood. Here we conducted a field campaign during a winter haze episode in urban Beijing, China to monitor gaseous and particulate NACs at 2-h time resolution. Through a standard-independent non-targeted approach, a total of 238 NACs were screened, of which 127 species were assigned chemical formula and 25 structures were confirmed. Four main classes were identified: nitrated aromatic hydrocarbons, nitrophenols, oxygenated nitrated aromatic compounds, and nitrated heterocyclic aromatic compounds. Hierarchical clustering analysis revealed disparate temporal variances of diurnal or nocturnal elevation, among which different nitration formations were captured, i.e., daytime photochemical oxidation and nighttime heterogeneous reactions. Isomeric information, particularly the substitution position of the nitro group on biphenyl, further demonstrated a potential heterogeneous mechanism of electrophilic nitration by NO2+. Assisted by source apportionment, we found that nighttime heterogeneous reactions significantly contributed to NAC formation, e.g., 31.3 % and 60.8 %, respectively, to 2-nitrofluoranthene and 2-nitropyrene, which were previously considered as classical daytime gas-phase products. This study provides comprehensive information on urban NAC species and highlights the importance of unheeded heterogeneous reactions in the atmosphere.

9.
China CDC Wkly ; 6(2): 40-44, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38250701

RESUMO

What is already known about this topic?: Kashin-Beck disease (KBD) is a chronic and degenerative osteoarthropathy characterized by cartilage degeneration. It is an endemic disease that is highly prevalent among the Chinese population and poses a significant health risk. What is added by this report?: This is the first national report on the economic burden of KBD in China. According to the data from 2021, KBD has caused significant disease and economic burdens. The most substantial reduction in healthy life expectancy was observed among patients with degree II severity and those aged 60 years and older, resulting in a total indirect economic burden of 112.74 million Chinese Yuan (CNY). What are the implications for public health practice?: The results of this study will contribute to informing the development of tailored prevention and control strategies by the government. These strategies will include targeted policies and recommendations for appropriate healthcare and financial subsidies, which will be based on the demographic characteristics of the endemic areas.

10.
Nano Lett ; 24(3): 1034-1043, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38190456

RESUMO

Interfacial solar vapor generation holds great promise for alleviating the global freshwater crisis, but its real-world application is limited by the efficiently choppy water evaporation and industrial production capability. Herein, a self-floating solar evaporator with an underwater aerophilic surface is innovatively fabricated by weaving core-shell yarns via mature weaving techniques. The core-shell yarns possess capillary water channels in the hydrophilic cotton core and can trap air in the hydrophobic electrospinning nanofiber shell when submerged underwater, simultaneously realizing controllable water supplies, stable self-flotation, and great thermal insulation. Consequently, the self-floating solar evaporator achieves an evaporation rate of 2.26 kg m-2 h-1 under 1 sun irradiation, with a reduced heat conduction of 70.18 W m-2. Additionally, for the first time, a solar evaporator can operate continuously in water with varying waveforms and intensities over 24 h, exhibiting an outdoor cumulative evaporation rate of 14.17 kg m-2 day-1.

11.
Elife ; 122023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38131294

RESUMO

Background: Emerging data have supported the immunostimulatory role of radiotherapy, which could exert a synergistic effect with immune checkpoint inhibitors (ICIs). With proven effective but suboptimal effect of ICI and chemotherapy in triple-negative breast cancer (TNBC), we designed a pilot study to explore the efficacy and safety of neoadjuvant stereotactic body radiotherapy (SBRT) plus adebrelimab and chemotherapy in TNBC patients. Methods: Treatment-naïve TNBC patients received two cycles of intravenous adebrelimab (20 mg/kg, every 3 weeks), and SBRT (24 Gy/3 f, every other day) started at the second cycle, then followed by six cycles of adebrelimab plus nab-paclitaxel (125 mg/m² on days 1 and 8) and carboplatin (area under the curve 6 mg/mL per min on day 1) every 3 weeks. The surgery was performed within 3-5 weeks after the end of neoadjuvant therapy. Primary endpoint was pathological complete response (pCR, ypT0/is ypN0). Secondary endpoints included objective response rate (ORR), residual cancer burden (RCB) 0-I, and safety. Results: 13 patients were enrolled and received at least one dose of therapy. 10 (76.9%) patients completed SBRT and were included in efficacy analysis. 90% (9/10) of patients achieved pCR, both RCB 0-I and ORR reached 100% with three patients achieved complete remission. Adverse events (AEs) of all-grade and grade 3-4 occurred in 92.3% and 53.8%, respectively. One (7.7%) patient had treatment-related serious AEs. No radiation-related dermatitis or death occurred. Conclusions: Adding SBRT to adebrelimab and neoadjuvant chemotherapy led to a substantial proportion of pCR with acceptable toxicities, supporting further exploration of this combination in TNBC patients. Funding: None. Clinical trial number: NCT05132790.


Assuntos
Radiocirurgia , Neoplasias de Mama Triplo Negativas , Humanos , Anticorpos Monoclonais/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Inibidores de Checkpoint Imunológico/uso terapêutico , Terapia Neoadjuvante/efeitos adversos , Projetos Piloto , Resultado do Tratamento , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/radioterapia
12.
Small ; : e2307005, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37940625

RESUMO

Solar-driven interfacial desalination is widely considered to be a promising technology to address the global water crisis. This study proposes a novel electrospun nanofiber-based all-in-one vertically interfacial solar evaporator endowed with a high steam generation rate, steady omnidirectional evaporation, and enduring ultrahigh-salinity brine desalination. In particular, the electrospun nanofiber is collected into the tubular structure, followed by spraying with a dense crosslinked poly(vinyl alcohol) film, which renders them sufficiently strong for the preparation of a vertically array evaporator. The integrated evaporator made an individual capillary as a unit to form multiple thermal localization interfaces and steam dissipation channels, realizing zone heating of water. Thus a high steam generation rate exceeding 4.0 kg m-2  h-1 in pure water is demonstrated even under omnidirectional sunlight, and outperforms existing evaporators. Moreover, salt ions in the photothermal layer can be effectively transported to the water in capillaries and subsequently exchanged with the bulk water due to the strong action of capillary force, which ensures an ultrahigh desalination rate (≈12.5 kg m-2  h-1 under 3 sun) in 25 wt% concentration brine over 300 min. As such, this work provides a meaningful roadmap for the development of state-of-the-art solar-driven interfacial desalination.

13.
Metabolites ; 13(11)2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-37999254

RESUMO

Metabolic activities within the gut microbiome are intimately linked to human health and disease, especially within the context of environmental exposure and its potential ramifications. Perturbations within this microbiome, termed "gut microbiome perturbations", have emerged as plausible intermediaries in the onset or exacerbation of diseases following environmental chemical exposures, with fluoride being a compound of particular concern. Despite the well-documented adverse impacts of excessive fluoride on various human physiological systems-ranging from skeletal to neurological-the nuanced dynamics between fluoride exposure, the gut microbiome, and the resulting dose-response relationship remains a scientific enigma. Leveraging the precision of 16S rRNA high-throughput sequencing, this study meticulously examines the ramifications of diverse fluoride concentrations on the gut microbiome's composition and functional capabilities within Wistar rats. Our findings indicate a profound shift in the intestinal microbial composition following fluoride exposure, marked by a dose-dependent modulation in the abundance of key genera, including Pelagibacterium, Bilophila, Turicibacter, and Roseburia. Moreover, discernible alterations were observed in critical functional and metabolic pathways of the microbiome, such as D-lyxose ketol-isomerase and DNA polymerase III subunit gamma/tau, underscoring the broad-reaching implications of fluoride exposure. Intriguingly, correlation analyses elucidated strong associations between specific bacterial co-abundance groups (CAGs) and these shifted metabolic pathways. In essence, fluoride exposure not only perturbs the compositional equilibrium of the gut microbiota but also instigates profound shifts in its metabolic landscape. These intricate alterations may provide a mechanistic foundation for understanding fluoride's potential toxicological effects mediated via gut microbiome modulation.

14.
Exp Biol Med (Maywood) ; 248(18): 1579-1587, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37786374

RESUMO

Non-invasive positive-pressure ventilation (NIPPV) has been demonstrated to exhibit a cardioprotective function in a rat model of myocardial infarction (MI). However, the mechanism underlying NIPPV-mediated MI progression requires further investigation. We aimed to investigate the effectiveness and corresponding mechanism of NIPPV in an acute MI-induced heart failure (HF) rat model. Thirty each of healthy wild type (WT) and apoptosis signal-regulating kinase 1 (ASK-1)-deficient rats were enrolled in this study. MI models were established via anterior descending branch ligation of the left coronary artery. The corresponding data indicated that NIPPV treatment reduced the heart infarct area, myocardial fibrosis degree, and cardiac function loss in MI rats, and ameliorated apoptosis and reactive oxygen species (ROS) levels in the heart tissue. Furthermore, the expression level of ASK-1 level, a key modulator of the ROS-induced extrinsic apoptosis pathway, was upregulated in the heart tissues of MI rats, but decreased after NIPPV treatment. Meanwhile, the downstream cleavage of caspase-3, caspase-9, and PARP, alongside p38 phosphorylation and FasL expression, exhibited a similar trend to that of ASK-1 expression. The involvement of ASK-1 in NIPPV-treated MI in ASK-1-deficient rats was examined. Although MI modeling indicated that cardiac function loss was alleviated in ASK-1-deficient rats, NIPPV treatment did not confer any clear efficiency in cardiac improvement in ASK-1-knockdown rats with MI modeling. Nonetheless, NIPPV inhibited ROS-induced extrinsic apoptosis in the heart tissues of rats with MI by regulating ASK-1 expression, and subsequently ameliorated cardiac function loss and MI-dependent pathogenic changes in the heart tissue.


Assuntos
Insuficiência Cardíaca , Infarto do Miocárdio , Ratos , Animais , Miócitos Cardíacos/metabolismo , Respiração Artificial , Espécies Reativas de Oxigênio , Infarto do Miocárdio/patologia , Insuficiência Cardíaca/patologia , Apoptose
15.
Langmuir ; 39(38): 13641-13648, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37696039

RESUMO

Solar-driven interface desalination (SDID) is a promising and sustainable technology that produces freshwater from brine. Ionic hydrogels are effective evaporators, providing enhanced interaction with water and ions due to the charged groups on hydrophilic polymer networks. In this study, we developed a hydrogel-based solar steam generator with a gradient-charged (GC) structure for desalination. The gradient-charged groups' distribution on the hydrogels creates gradients of free water and osmotic pressure, realizing rapid water supplement as well as desalination of concentrated brine. Consequently, the GC hydrogel demonstrated an exceptional water evaporation rate, achieving a value as high as 2.61 kg m-2 h-1 in pure water and 1.72 kg m-2 h-1 on treating with 20 wt % NaCl solution under one sun illumination. Following the substantial solar-driven evaporation, impurities, including salt and other pollutants, were removed, thereby ensuring the purity of the condensed water. Overall, the GC hydrogel-based evaporator is a promising solution for SDID to achieve effective and sustainable water desalination.

16.
Soft Matter ; 19(34): 6458-6467, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37606536

RESUMO

As the cohesive properties (such as the enthalpy of sublimation) of solid organic salts (or ionic liquids, ILs) are unmeasurable, a method of their indirect determination is proposed in this paper. For this purpose, the thermogravimetric analysis (TGA) and differential scanning calorimetric analysis (DSC) were carried out over a wide range of temperatures. In this study, the mathematical relationship of the thermodynamic properties between the liquid and solid phases of ILs is established using the Born-Fajans-Haber cycle, in which the sum of the vaporization enthalpy of ILs, melting enthalpy and the enthalpy of solid-solid phase transition is regarded as the sublimation enthalpy of solid organic salts. With this method, the cohesive properties of tetrabutylammonium bis(trifluoromethanesulfonyl)imide ([N4444][NTf2]), which is an aprotic IL, were successfully obtained. Additionally, the difference between the lattice energy and the cohesive energy was employed to quantitatively calculate the charge separation distance of single ion pair (r12) in the gas phase of ionic liquids for the first time, which can serve as a standard methodology to measure the closeness in distance between the anion and the cation in a gas phase ion pair. The pyrolysis mechanism of [N4444][NTf2] was also explored.

17.
Oncol Lett ; 25(6): 246, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37153055

RESUMO

Cervical cancer (CC) is the most common human papillomavirus-related disease. Continuous activation of the NF-κB signaling pathway has been observed in CC. SHC binding and spindle associated 1 (SHCBP1) contributes to tumorigenesis and activation of the NF-κB pathway in multiple cancer types, while its function in CC remains unclear. In the present study, three Gene Expression Omnibus datasets were used to identify differentially expressed genes (DEGs) in CC. Loss- and gain-of-function experiments were performed using stable SHCBP1-silenced and SHCBP1-overexpressing CC cells. To further explore the molecular mechanism of SHCBP1 in CC, small interfering RNA targeting eukaryotic translation initiation factor 5A (EIF5A) was transfected into stable SHCBP1-overexpressing CC cells. The results demonstrated that SHCBP1 was an upregulated DEG in CC tissues compared with healthy control cervical tissues. Functional experiments revealed the pro-proliferative and pro-stemness role of SHCBP1 in CC cells (CaSki and SiHa cells), in vitro. Furthermore, the NF-κB signaling pathway in CC cells was activated by SHCBP1. Increases in cell proliferation, stemness and activation of NF-κB, induced by SHCBP1 overexpression in CC cells, were reversed by EIF5A knockdown. Taken together, the results indicated that SHCBP1 serves an important role in regulation of CC cell proliferation, self-renewal and activation of NF-κB via EIF5A. The present study demonstrated a potential molecular mechanism underlying the progression of CC.

18.
Sci Total Environ ; 887: 164114, 2023 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-37182762

RESUMO

Organosulfur compounds (OSCs) are important components of fine particulate matter (PM2.5); however, little information is available on OSCs in urban regions due to their chemical complexity, especially for novel species such as aromatic sulfonates. To supplement the detection technique and systematically identify OSCs, in this study we developed a nontargeted approach based on gas chromatography and high-resolution mass spectrometry (GC-HRMS) to screen OSCs in PM2.5 of urban Beijing and provide field evidence for their source and formation mechanism. 76 OSCs were found through mass difference of sulfur isotopes and characteristic sulfur-containing fragments. 6 species were confirmed as aromatic sulfonates by authentic standards. 32 OSCs showed higher levels in the heating season, presumably because of the intensive emission, especially from coal combustion. While certain species, with 2-sulfobenzoic acid as the representative, were 2.6-times higher in the non-heating season than in the heating season. Such species were significantly correlated with ozone and aerosol liquid water content (r = 0.2-0.8, p < 0.05), implying an oxidation-involved aqueous-phase formation in the atmosphere. In addition, with an average proportion of ∼95 % of the total sulfobenzoic acids, the predominance of the 2-substitution product over its isomers of 3- or 4-sulfobenzoic acid suggests a more plausible mechanism of radical-initiated reaction of phthalic acid followed by sulfonation, with atmospheric reactivity indicated by ozone and temperature as the determining factor. This study provided not only a nontargeted approach for OSCs in ambient PM2.5, but also field evidence on their secondary formation proposed in previous simulation studies.

19.
Environ Sci Technol ; 57(13): 5160-5168, 2023 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-36940425

RESUMO

Polar nitrated aromatic compounds (pNACs) are key ambient brown carbon chromophores; however, their formation mechanisms, especially in the aqueous phase, remain unclear. We developed an advanced technique for pNACs and measured 1764 compounds in atmospheric fine particulate matter sampled in urban Beijing, China. Molecular formulas were derived for 433 compounds, of which 17 were confirmed using reference standards. Potential novel species with up to four aromatic rings and a maximum of five functional groups were found. Higher concentrations were detected in the heating season, with a median of 82.6 ng m-3 for Σ17pNACs. Non-negative matrix factorization analysis indicated that primary emissions particularly coal combustion were dominant in the heating season. While in the non-heating season, aqueous-phase nitration could generate abundant pNACs with the carboxyl group, which was confirmed by their significant association with the aerosol liquid water content. Aqueous-phase formation of 3- and 5-nitrosalicylic acids instead of their isomer of 4-hydroxy-3-nitrobenzoic acid suggests the existence of an intermediate where the intramolecular hydrogen bond favors kinetics-controlled NO2• nitration. This study provides not only a promising technique for the pNAC measurement but also evidence for their atmospheric aqueous-phase formation, facilitating further evaluation of pNACs' climatic effects.


Assuntos
Poluentes Atmosféricos , Hidrocarbonetos Policíclicos Aromáticos , Material Particulado/análise , Poluentes Atmosféricos/análise , Nitrocompostos , Monitoramento Ambiental , China , Estações do Ano
20.
Histochem Cell Biol ; 159(5): 439-451, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36602585

RESUMO

Cervical cancer (CC) is the primary cancer-related cause of morbidity and mortality in women. Previous studies have shown that placenta-specific 8 (PLAC8) has different functions in multiple malignancies. This study aimed to explore the function and regulatory mechanism of PLAC8 in CC. Bioinformatics and immunohistochemical analyses demonstrated that PLAC8 was significantly upregulated in CC tissues compared with normal tissues. Gain/loss-of-function experiments showed that siRNA-mediated knockdown of PLAC8 suppressed cell migration and invasion, while PLAC8 overexpression promoted cell motility. Moreover, PLAC8 was revealed to affect the epithelial-mesenchymal transition (EMT) process by upregulating epithelial (E)-cadherin and decreasing the expression of mesenchymal markers of EMT, including vimentin, zinc finger E-box binding homeobox 1 (ZEB1), neural (N)-cadherin, matrix metalloproteinase-9 (MMP-9), and MMP-2 in PLAC8-silenced cells. PLAC8 activated the AKT pathway, as proven by the downregulation of p-AKTSer473 and p-AKTThr308 expression after PLAC8 knockdown. Furthermore, PLAC8 overexpression upregulated the expression of sex-determining region Y-related high-mobility group box transcription factor 4 (SOX4), which is reported to mediate the activation of the AKT pathway, and SOX4 deficiency reversed the cellular functions caused by PLAC8 overexpression. Overall, the present study indicates that PLAC8 may facilitate CC development by activating the SOX4-mediated AKT pathway, suggesting that PLAC8 may serve as a potential biomarker for CC treatment.


Assuntos
Proteínas Proto-Oncogênicas c-akt , Neoplasias do Colo do Útero , Humanos , Feminino , Proteínas Proto-Oncogênicas c-akt/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Caderinas/metabolismo , Transição Epitelial-Mesenquimal , Movimento Celular , Regulação Neoplásica da Expressão Gênica , Homeobox 1 de Ligação a E-box em Dedo de Zinco/genética , Homeobox 1 de Ligação a E-box em Dedo de Zinco/metabolismo , Fatores de Transcrição SOXC/genética , Fatores de Transcrição SOXC/metabolismo , Proteínas/metabolismo
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