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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 315: 124248, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38599026

RESUMO

Ferroptosis is a type of lipid peroxidation-induced apoptosis brought on by imbalances in iron metabolism and redox. It involves both the thiol-associated anti-ferroptosis pathway and the excessive buildup of reactive oxygen species (ROS), which stimulates the ferroptosis pathway. Determining the precise control mechanism of ferroptosis requires examining the dynamic connection between reactive sulfur species (RSS) and ROS. Cysteine (Cys) and peroxynitrite (ONOO-) are highly active redox species in organisms and play dynamic roles in the ferroptosis process. In this study, a coumarin dye was conjugated with specific response sites for Cys and ONOO-, enabling the simultaneous detection of Cys and ONOO- through the green and red fluorescence channels, respectively (λem = 498 nm for Cys and λem = 565 nm for ONOO-). Using the probe LXB, we monitored the changes in Cys and ONOO- levels in the ferroptosis pathway induced by erastin. The results demonstrate a significant generation of ONOO- and a noticeable decrease in intracellular Cys levels at the beginning upon erastin treatment and finally maintains a relatively low level. This study presents the first probe to investigate the intracellular redox modulation and control between Cys and ONOO- during ferroptosis, providing valuable insights into the potential mutual correlation between Cys and ONOO- in this process.


Assuntos
Cisteína , Ferroptose , Corantes Fluorescentes , Ácido Peroxinitroso , Ferroptose/efeitos dos fármacos , Corantes Fluorescentes/química , Cisteína/metabolismo , Cisteína/análise , Humanos , Ácido Peroxinitroso/análise , Ácido Peroxinitroso/metabolismo , Espectrometria de Fluorescência , Oxirredução , Piperazinas/farmacologia , Piperazinas/química , Cumarínicos/química , Cumarínicos/farmacologia
2.
Med Mycol Case Rep ; 43: 100630, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38323302

RESUMO

We report a case of a 20-year-old young woman with a large stucco keratosis in the mons veneris, one of the clinical variants of Seborrheic keratoses (SKs). Periodic acid-Schiff staining revealed a large number of Malassezia spores in the stratum corneum. After oral antifungal treatment with itraconazole for 4 weeks, the benign tumor was completely cleared without residue or recurrence, which may open a new perspective for exploring the pathogenesis of SKs.

3.
Dalton Trans ; 52(45): 16911-16919, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37927054

RESUMO

The catalytic activity of a transition metal (host) oxide can be influenced by doping with a second cation (dopant), but the key factors dominating the activity of the doped catalyst are still controversial. Herein, CeO2 doped with Ni, Mn, and Y catalysts prepared using aerosol pyrolysis were used to demonstrate the positive, negative, and additive effects on CO oxidation as a model reaction. Various characterization results indicated that Ni, Mn, and Y had been successfully doped into the CeO2 lattice. The catalytic activities of each catalyst for CO conversion were in the order of Ni-CeO2 > Mn-CeO2 > CeO2 > Y-CeO2. Operando DRIFTS-MS and various characterization methods were applied to reveal the intrinsic nature of the doping effects. The accumulation rate of the surface bidentate carbonates determined the CO oxidation. A definition to evaluate the doping effect was proposed, which is anticipated to be useful for developing a rational catalyst with a high CO oxidation activity. The CO oxidation reactivities displayed strong correlations with the surface factors obtained from operando DRIFTS-MS analysis and the structure factors from XPS and Raman analyses.

4.
Molecules ; 28(19)2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37836722

RESUMO

Pt-based catalysts exhibit unique catalytic properties in many chemical reactions. In particular, metal-support interactions (MSI) greatly improve catalytic activity. However, the current MSI mechanism between platinum (Pt) and the support is not clear enough. In this paper, the interaction of 1 wt% Pt nanoparticles (NPs) on ß-MnO2 in carbon monoxide (CO) oxidation was studied. The Pt on ß-MnO2 inhibited CO oxidation below 210 °C but promoted it above 210 °C. A Pt/ß-MnO2 catalyst contains more Pt4+ and less Pt2+. The results of operando DRIFTS-MS show that surface-terminal-type oxygen (M=O) plays an important role in CO oxidation. When the temperature was below 210 °C, Mn=O consumption on Pt/ß-MnO2 was less than ß-MnO2 due to Pt4+ inhibition on CO oxidation. When the temperature was above 210 °C, Pt4+ was reduced to Pt2+, and Mn=O consumption due to CO oxidation was greater than ß-MnO2. The interaction of Pt and ß-MnO2 is proposed.

5.
Langmuir ; 39(44): 15773-15784, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37883132

RESUMO

The aerosol pyrolysis method from nitrate precursors was used to prepare the Mn-CeO2 catalyst containing Mn2O3, CeO2, and Mn-doped CeO2 nanoparticles for catalyzing carbonous soot oxidation. The prepared Mn-CeO2 catalysts have high specific surface areas, Ce3+ ratio, and oxygen vacancy defects; these are a benefit for soot oxidation. The T50 for soot oxidation on the 0.57Mn-CeO2 catalyst is as low as 355 °C, which is 329 °C lower than that for soot oxidation without a catalyst. The catalysts were characterized using XRD, SEM-EDS, HRTEM, XPS, Raman spectroscopy, H2-TPR-MS, O2-TPD-MS, soot-TPR-MS, and operando DRIFTS-MS. The functions of Mn2O3, CeO2, and Mn-doped CeO2 in the 0.57Mn-CeO2 catalyst are unveiled. Mn-doped CeO2 plays a key role and CeO2 participates in soot oxidation, while Mn2O3 is used to enhance higher ratios of Ce3+, via the reaction of Mn3+ + Ce4+ = Mn4+ + Ce3+. The mechanism of soot oxidation on Mn-CeO2 was proposed.

6.
Biosci Trends ; 17(4): 252-261, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37612123

RESUMO

With the intensification of population aging worldwide, the health problems of the elderly have become a particular concern. Functional disability is a prominent problem in the aging of this population, resulting in the decreased quality of life of senile people. Risk factors for functional disability in the elderly include geriatric syndromes and the associated diseases such as frailty. The influence of frailty on the health of the elderly has been a hot topic in recent years. As a dynamic and reversible geriatric syndrome, it has become one of the important public health problems emerging around the world. Frailty lies between self-reliance and the need for care and is reversible. Reasonable preventive interventions can restore the elderly to an independent life. If no interventions are implemented, the elderly will face a dilemma. There is no gold standard for frailty screening around the world. In order to alleviate frailty in the elderly, many countries have conducted early screening for frailty, mainly focusing on nutrition, physical activity, and social participation, in order to detect and prevent frailty earlier and to reduce the incidence of frailty. This topic provides an overview of the current status of frailty, early screening for frailty, and the interventions for frailty in most countries of the world.


Assuntos
Fragilidade , Envelhecimento Saudável , Idoso , Humanos , Envelhecimento , Exercício Físico , Fragilidade/diagnóstico , Fragilidade/prevenção & controle , Qualidade de Vida
7.
Entropy (Basel) ; 25(7)2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37509994

RESUMO

Quantum key distribution (QKD) is a promising technique to resist the threat against quantum computers. However, the high loss of quantum signals over a long-distance optical fiber is an obstacle for QKD in the intercontinental domain. In this context, the quantum satellite network is preferred over the terrestrial quantum optical network. Due to the mobility of satellites, the satellite topology is dynamic in the quantum satellite network, which remains a challenge for routing. In hybrid geostationary-earth-orbit (GEO)/low-earth-orbit (LEO) quantum satellite networks, the lack of an efficient scheduling scheme for GEO/LEO satellites also limits the construction of quantum satellite networks. Therefore, this paper provides a topology abstraction-based routing scheme for secret-key provisioning, where the dynamic physical topology is translated into a quasi-static abstracted topology. This scheme contributes to saving the precious secret key resources. In order to improve the success probability of long-distance QKD requests, three novel resource-scheduling heuristic algorithms are proposed in hybrid GEO/LEO quantum satellite networks. Simulation results indicate that the proposed algorithms can improve the success probability of QKD requests by 47% compared to the benchmark.

8.
Plants (Basel) ; 12(13)2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-37446969

RESUMO

Temperature stresses, including low- and high-temperature stresses, are the main abiotic stresses affecting rice yield. Due to global climate change, the impact of temperature pressure on rice yield is gradually increasing, which is also a major concern for researchers. In this study, an H1 histone in Oryza sativa (OsHis1.1, LOC_Os04g18090) was cloned, and its role in rice's response to temperature stresses was functionally characterized. The GUS staining analysis of OsHis1.1 promoter-GUS transgenic rice showed that OsHis1.1 was widely expressed in various rice tissues. Transient expression demonstrated that OsHis1.1 was localized in the nucleus. The overexpression of OsHis1.1 reduces the tolerance to temperature stress in rice by inhibiting the expression of genes that are responsive to heat and cold stress. Under stress conditions, the POD activity and chlorophyll and proline contents of OsHis1.1-overexpression rice lines were significantly lower than those of the wild type, while the malondialdehyde content was higher than that of the wild type. Compared with Nip, OsHis1.1-overexpression rice suffered more serious oxidative stress and cell damage under temperature stress. Furthermore, OsHis1.1-overexpression rice showed changes in agronomic traits.

9.
Rice (N Y) ; 16(1): 31, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37468664

RESUMO

Haloacid dehalogenase-like hydrolase (HAD) superfamily have been shown to get involved in plant growth and abiotic stress response. Although the various functions and regulatory mechanism of HAD superfamily have been well demonstrated, we know little about the function of this family in conferring abiotic stress tolerance to rice. Here, we report OsHAD3, a HAD superfamily member, could affect drought tolerance of rice. Under drought stress, overexpression of OsHAD3 increases the accumulation of reactive oxygen species and malondialdehyde than wild type. OsHAD3-overexpression lines decreased but antisense-expression lines increased the roots length under drought stress and the transcription levels of many well-known stress-related genes were also changed in plants with different genotypes. Furthermore, overexpression of OsHAD3 also decreases the oxidative tolerance. Our results suggest that overexpression of OsHAD3 could decrease the drought tolerance of rice and provide a new strategy for improving drought tolerance in rice.

10.
Cancer Cell ; 41(6): 1118-1133.e12, 2023 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-37267951

RESUMO

Cyclic GMP-AMP synthase (cGAS) is the major sensor for cytosolic DNA and activates type I interferon signaling and plays an essential role in antitumor immunity. However, it remains unclear whether the cGAS-mediated antitumor activity is affected by nutrient status. Here, our study reports that methionine deprivation enhances cGAS activity by blocking its methylation, which is catalyzed by methyltransferase SUV39H1. We further show that methylation enhances the chromatin sequestration of cGAS in a UHRF1-dependent manner. Blocking cGAS methylation enhances cGAS-mediated antitumor immunity and suppresses colorectal tumorigenesis. Clinically, cGAS methylation in human cancers correlates with poor prognosis. Thus, our results indicate that nutrient stress promotes cGAS activation via reversible methylation, and suggest a potential therapeutic strategy for targeting cGAS methylation in cancer treatment.


Assuntos
Cromatina , Metionina , Humanos , Cromatina/genética , Metionina/genética , Nucleotidiltransferases/genética , Nucleotidiltransferases/metabolismo , DNA , Imunidade Inata , Desmetilação , Proteínas Estimuladoras de Ligação a CCAAT/genética , Ubiquitina-Proteína Ligases/genética
11.
J Surg Res ; 290: 266-275, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37321147

RESUMO

INTRODUCTION: Ferroptosis is a new type of regulated cell death that is characterized by the overwhelming iron-dependent accumulation of lethal lipid reactive oxygen species and is involved in various diseases. However, the relationship between ferroptosis and lipopolysaccharide (LPS)-induced acute lung injury (ALI) remains largely unknown. METHODS: In this study, iron metabolism and ferroptosis-related gene mRNA levels in the lung tissues of LPS-induced ALI mice at different time points were detected. Then, the histological, cytokines production, and iron levels of LPS-induced ALI mice with or without the pretreatment of the ferroptosis inhibitor ferrostatin-1 (Fer-1) were measured after mice received the ferroptosis inhibitor ferrostatin-1 (Fer-1) intraperitoneally before LPS administration. Ferroptosis-related protein (GPX4, NRF2, and DPP4) expression was measured in the in vivo and in vitro ALI model. Finally, ROS accumulation and lipid peroxidation was measured in in vivo and in vitro study. RESULTS: Our results showed that iron metabolism and ferroptosis-related gene mRNA demonstrated significant variation in LPS-treated pulmonary tissues. The ferroptosis inhibitor Fer-1 markedly attenuated the histologic injuries of the lung tissue and suppressed the production of cytokines in bronchoalveolar lavage fluid (BALF). Fer-1 administration reduced the levels of NRF2 and DPP4 protein induced by the LPS challenge. Furthermore, Fer-1 reversed the tendency of iron metabolism, MDA, SOD, and GSH levels induced by LPS administration in in vivo and in vitro. CONCLUSIONS: Taken together, ferroptosis inhibition by ferrostatin-1 alleviated acute lung injury through modulating oxidative lipid damages induced by the LPS challenge.


Assuntos
Lesão Pulmonar Aguda , Lipopolissacarídeos , Animais , Camundongos , Lipopolissacarídeos/toxicidade , Dipeptidil Peptidase 4 , Fator 2 Relacionado a NF-E2 , Estresse Oxidativo , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/tratamento farmacológico , Citocinas , RNA Mensageiro , Ferro
12.
Molecules ; 28(8)2023 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-37110744

RESUMO

Cu-doped manganese oxide (Cu-Mn2O4) prepared using aerosol decomposition was used as a CO oxidation catalyst. Cu was successfully doped into Mn2O4 due to their nitrate precursors having closed thermal decomposition properties, which ensured the atomic ratio of Cu/(Cu + Mn) in Cu-Mn2O4 close to that in their nitrate precursors. The 0.5Cu-Mn2O4 catalyst of 0.48 Cu/(Cu + Mn) atomic ratio had the best CO oxidation performance, with T50 and T90 as low as 48 and 69 °C, respectively. The 0.5Cu-Mn2O4 catalyst also had (1) a hollow sphere morphology, where the sphere wall was composed of a large number of nanospheres (about 10 nm), (2) the largest specific surface area and defects on the interfacing of the nanospheres, and (3) the highest Mn3+, Cu+, and Oads ratios, which facilitated oxygen vacancy formation, CO adsorption, and CO oxidation, respectively, yielding a synergetic effect on CO oxidation. DRIFTS-MS analysis results showed that terminal-type oxygen (M=O) and bridge-type oxygen (M-O-M) on 0.5Cu-Mn2O4 were reactive at a low temperature, resulting in-good low-temperature CO oxidation performance. Water could adsorb on 0.5Cu-Mn2O4 and inhibited M=O and M-O-M reaction with CO. Water could not inhibit O2 decomposition to M=O and M-O-M. The 0.5Cu-Mn2O4 catalyst had excellent water resistance at 150 °C, at which the influence of water (up to 5%) on CO oxidation could be completely eliminated.

13.
Folia Microbiol (Praha) ; 68(4): 595-605, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36753031

RESUMO

Cryptococcus neoformans is an opportunistic fungal pathogen that can cause life-threatening invasive fungal infections. As its prevalence and drug resistance continue to rise, cryptococcosis requires new treatment options. Tapping into the potential antifungal effects of traditional drugs or combination therapy has become one of the options. This study was the first to examine the interaction of hydroxychloroquine (HCQ) and itraconazole (ITR) on Cryptococcus neoformans in vitro and in vivo. Our results showed that HCQ alone and in combination with ITR exhibited antifungal activity against C. neoformans planktonic cells. When HCQ was combined with ITR, the minimal inhibitory concentration (MIC) value of HCQ decreased to 32 µg/mL, and the MIC value of ITR decreased from 0.25 µg/mL to 0.06-0.25 µg/mL. The time-killing curve showed that the combined application of HCQ and ITR significantly shortened the killing time, dynamically defining the antifungal activity. The minimum biofilm clearance concentration (MBEC) of HCQ was only 32 µg/mL, which was significantly lower than the MIC of HCQ for planktonic cells. When combined with ITR, the MBEC of ITR decreased from 128 µg/mL to 2-1 µg/mL, and the MBEC of HCQ decreased from 32 µg/mL to 4 µg/mL, indicating a synergistic antifungal biofilm effect. In comparison to ITR alone, the combination of HCQ and ITR treatment increased the survival of C. neoformans-infected Galleria mellonella larvae and decreased the fungal burden of infected larvae. Mechanistic investigations revealed that HCQ might damage C. neoformans cell membranes, impact the structure of fungal cells, cause extracellular material leakage, and have a potent affinity for attaching to the C. neoformans genomic DNA. In conclusion, HCQ has potential clinical application in the treatment of cryptococcosis.


Assuntos
Criptococose , Cryptococcus neoformans , Animais , Itraconazol/farmacologia , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Hidroxicloroquina/farmacologia , Hidroxicloroquina/uso terapêutico , Criptococose/tratamento farmacológico , Criptococose/microbiologia , Testes de Sensibilidade Microbiana
14.
Environ Sci Technol ; 57(9): 3864-3874, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36812295

RESUMO

In this study, based on the comparison of two counterparts [Mn- and Cr-modified CeO2 nanobelts (NBs)] with the opposite effects, some novel mechanistic insights into the ethyl acetate (EA) catalytic combustion over CeO2-based catalysts were proposed. The results demonstrated that EA catalytic combustion consisted of three primary processes: EA hydrolysis (C-O bond breakage), the oxidation of intermediate products, and the removal of surface acetates/alcoholates. Rapid EA hydrolysis typically occurs on surface acid/base sites or hydroxyl groups, and the removal of surface acetates/alcoholates resulting from EA hydrolysis is considered the rate-determining step. The deposited acetates/alcoholates like a shield covered the active sites (such as surface oxygen vacancies), and the enhanced mobility of the surface lattice oxygen as an oxidizing agent played a vital role in breaking through the shield and promoting the further hydrolysis-oxidation process. The Cr modification impeded the release of surface-activated lattice oxygen from the CeO2 NBs and induced the accumulation of acetates/alcoholates at a higher temperature due to the increased surface acidity/basicity. Conversely, the Mn-substituted CeO2 NBs with the higher lattice oxygen mobility effectively accelerated the in situ decomposition of acetates/alcoholates and facilitated the re-exposure of surface active sites. This study may contribute to a further mechanistic understanding into the catalytic oxidation of esters or other oxygenated volatile organic compounds over CeO2-based catalysts.


Assuntos
Acetatos , Oxigênio , Hidrólise , Oxirredução , Acetatos/química
15.
Environ Sci Technol ; 57(2): 909-919, 2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36594719

RESUMO

The knowledge of the chemical composition of brown carbon (BrC) is limited to the categories of components or parts of specific organic components. In this paper, the light-absorbing properties and molecular compositions of lipid-soluble organic components in fine particulate matter of Beijing from 2016 to 2018, characterized by an ultraviolet-visible spectrometer and gas chromatography coupled with time-of-flight mass spectrometry, respectively, were combined to untargetedly screen the key BrC molecules by a partial least squares regression model for the first time. A total of 421 molecules were obtained, where 61 molecules were identified qualitatively and 22 molecules quantitatively. To the best of our knowledge, 11 molecules were newly identified BrC species. These qualitative molecules included polycyclic aromatic hydrocarbons with higher ambient concentrations and mass absorbing efficiencies (MAEs), as well as oxygen- and nitrogen-containing aromatic components with relatively lower concentrations and MAEs. The absorption contribution at 365 nm of quantified BrC species to lipid-soluble BrC during heating seasons was 39.1 ± 17.0%, which was about 5 times as high as previous studies. These results help establish a complete BrC molecular database and provide data support for better evaluating the climate effect of atmospheric carbonaceous aerosols and formulating air pollution control strategies.


Assuntos
Poluentes Atmosféricos , Carbono , Pequim , Cromatografia Gasosa-Espectrometria de Massas , Monitoramento Ambiental/métodos , Material Particulado/análise , Espectrometria de Massas , Aerossóis/análise , Lipídeos , Poluentes Atmosféricos/análise
16.
RSC Adv ; 13(3): 1738-1750, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36712644

RESUMO

The development of excellent selective catalytic reduction (SCR) catalysts with hydrocarbons for lean-burn diesel engines is of great significance, and a range of novel catalysts loaded with Sn and Ag were studied in this work. It was found that the synergistic effects of Sn and Ag enabled the 1Sn5Ag/γ-Al2O3 (1 wt% Sn and 5wt% Ag) to exhibit superior C3H6-SCR performance. The de-NO x efficiency was maintained above 80% between 336 and 448 °C. The characterization results showed that the presence of AgCl crystallites in the 1Sn5Ag/γ-Al2O3 catalyst helped its redox ability maintain an appropriate level, which suppressed the over-oxidation of C3H6. Besides, the number of surface adsorbed oxygen (Oα) and hydroxyl groups (Oγ) were enriched, and their reactivity was greatly enhanced due to the coexistence of Ag and Sn. The ratio of Ag0/Ag+ was increased to 3.68 due to the electron transfer effects, much higher than that of Ag/γ-Al2O3 (2.15). Lewis acid sites dominated the C3H6-SCR reaction over the 1Sn5Ag/γ-Al2O3 catalyst. The synergistic effects of Sn and Ag facilitated the formation of intermediates such as acetates, enolic species, and nitrates, and inhibited the deep oxidation of C3H6 into CO2, and the C3H6-SCR mechanism was carefully proposed.

17.
Stem Cells ; 41(2): 111-125, 2023 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-36583266

RESUMO

Glioblastoma stem cells (GSCs) contributed to the progression, treatment resistance, and relapse of glioblastoma (GBM). However, current researches on GSCs were performed usually outside the human tumor microenvironment, ignoring the importance of the cellular states of primary GSCs. In this study, we leveraged single-cell transcriptome sequencing data of 6 independent GBM cohorts from public databases, and combined lineage and stemness features to identify primary GSCs. We dissected the cell states of GSCs and correlated them with the clinical outcomes of patients. As a result, we constructed a cellular hierarchy where GSCs resided at the center. In addition, we identified and characterized 2 different and recurrent GSCs subpopulations: proliferative GSCs (pGSCs) and quiescent GSCs (qGSCs). The pGSCs showed high cell cycle activity, indicating rapid cell division, while qGSCs showed a quiescent state. Then we traced the processes of tumor development by pseudo-time analysis and tumor phylogeny, and found that GSCs accumulated throughout the whole tumor development period. During the process, pGSCs mainly contributed to the early stage and qGSCs were enriched in the later stage. Finally, we constructed an 8-gene prognostic signature reflecting pGSCs activity and found that patients whose tumors were enriched for the pGSC signature had poor clinical outcomes. Our study highlights the primary GSCs heterogeneity and its correlation to tumor development and clinical outcomes, providing the potential targets for GBM treatment.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/patologia , Células-Tronco Neoplásicas/metabolismo , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Análise de Célula Única , Microambiente Tumoral/genética
18.
Anim Biotechnol ; 34(4): 1005-1013, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34870558

RESUMO

Heat stress (HS) has a negative impact on the health and performance of dairy cows, resulting in economic losses. Damage to the intestinal epithelium is the main cause of the adverse effects of heat stress on bovine health. This study investigated the repair capability of L-arginine (L-Arg) in reducing the adverse effects of HS on bovine intestinal epithelial cells (BIECs). BIECs were treated as follows: (1) control cells were cultured at 37 °C continuously and received no L-Arg; (2) cells in HS group were grown at 42 °C for 6 h followed by 12 h at 37 °C; and (3) the L-Arg group was cultured at 42 °C for 6 h, then treated with L-Arg at 37 °C for 12 h. HS disrupted redox homeostasis and reduced viability in BIECs, while treatment with L-Arg (6 mmol/L) for 12 h markedly reduced the negative effects of HS. L-Arg protected cells by preventing HS-induced changes in mitochondrial membrane-potential, inflammation, apoptosis-related gene expression and regulation of antioxidant enzymes. The above results indicated that L-Arg reduced the level of damage from HS in BIECs by lowering oxidant stress and inflammation, suggesting that L-Arg could be an effective dietary addition to protect cows from adverse intestinal effects caused by HS.


Assuntos
Antioxidantes , Doenças dos Bovinos , Feminino , Bovinos , Animais , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Células Epiteliais/metabolismo , Arginina/farmacologia , Arginina/metabolismo , Resposta ao Choque Térmico , Inflamação/metabolismo
19.
Artigo em Inglês | MEDLINE | ID: mdl-36429753

RESUMO

This paper aims to investigate how air pollution may affect corporate green financial constraints. We assume that poor air quality can enhance the pressure of governments on environmental protection, which creates easier access to financing for firms' green investments and transitions, especially in emerging markets. Using a sample of Chinese-listed companies, we find that the level of green financial constraints is reduced when air quality deteriorates. This effect is more obvious in regions with stronger local government influence or fewer formal environmental regulations. To manage potential self-selection and endogeneity issues, fixed effects (FE), two-stage least squares (2SLS) with instrumental variables (IV), and propensity-score matching (PSM) approaches are used to verify the validity of our results. We link air pollution and financial constraints of green investment, and we fill a literature gap by considering whether the environment can have an impact on corporate green transformation. In the channel analysis, we identify that debt could be an important mechanism through which firms derive fewer green financial constraints. Our findings indicate that air pollution can be a crucial factor restricting corporate green investment and transformation, and managers in the context of emerging markets should be more attentive to green financing.


Assuntos
Poluição do Ar , Organizações , Conservação dos Recursos Naturais , Governo , China
20.
Sci Rep ; 12(1): 20404, 2022 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-36437265

RESUMO

Head and neck squamous cell carcinoma (HNSCC) is a highly heterogeneous malignancy with poor prognosis. This article aims to explore the clinical significance of cell differentiation trajectory in HNSCC, identify different molecular subtypes by consensus clustering analysis, and develop a prognostic risk model on the basis of differentiation-related genes (DRGs) for predicting the prognosis of HNSCC patients. Firstly, cell trajectory analysis was performed on single-cell RNA sequencing (scRNA-seq) data, four molecular subtypes were identified from bulk RNA-seq data, and the molecular subtypes were predictive of patient survival, clinical features, immune infiltration status, and expression of immune checkpoint genes (ICGs)s. Secondly, we developed a 10-DRG signature for predicting the prognosis of HNSCC patients by using weighted correlation network analysis (WGCNA), differential expression analysis, univariate Cox regression analysis, and multivariate Cox regression analysis. Then, a nomogram integrating the risk assessment model and clinical features can successfully predict prognosis with favorable predictive performance and superior accuracy. We projected the response to immunotherapy and the sensitivity of commonly used antitumor drugs between the different groups. Finally, we used the quantitative Reverse Transcription-Polymerase Chain Reaction (qRT-PCR) analysis and western blot to verify the signature. In conclusion, we identified distinct molecular subtypes by cell differentiation trajectory and constructed a novel signature based on differentially expressed prognostic DRGs, which could predict the prognosis and response to immunotherapy for patients and may provide valuable clinical applications in the treatment of HNSCC.


Assuntos
Neoplasias de Cabeça e Pescoço , Imunoterapia , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia , Prognóstico , Fatores Imunológicos , Diferenciação Celular/genética , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/terapia
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