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1.
Mol Ecol Resour ; : e13950, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38567644

RESUMO

Lignin, as an abundant organic carbon, plays a vital role in the global carbon cycle. However, our understanding of the global lignin-degrading microbiome remains elusive. The greatest barrier has been absence of a comprehensive and accurate functional gene database. Here, we first developed a curated functional gene database (LCdb) for metagenomic profiling of lignin degrading microbial consortia. Via the LCdb, we draw a clear picture describing the global biogeography of communities with lignin-degrading potential. They exhibit clear niche differentiation at the levels of taxonomy and functional traits. The terrestrial microbiomes showed the highest diversity, yet the lowest correlations. In particular, there were few correlations between genes involved in aerobic and anaerobic degradation pathways, showing a clear functional redundancy property. In contrast, enhanced correlations, especially closer inter-connections between anaerobic and aerobic groups, were observed in aquatic consortia in response to the lower diversity. Specifically, dypB and dypA, are widespread on Earth, indicating their essential roles in lignin depolymerization. Estuarine and marine consortia featured the laccase and mnsod genes, respectively. Notably, the roles of archaea in lignin degradation were revealed in marine ecosystems. Environmental factors strongly influenced functional traits, but weakly shaped taxonomic groups. Null mode analysis further verified that composition of functional traits was deterministic, while taxonomic composition was highly stochastic, demonstrating that the environment selects functional genes rather than taxonomic groups. Our study not only develops a useful tool to study lignin degrading microbial communities via metagenome sequencing but also advances our understanding of ecological traits of these global microbiomes.

3.
J Neurosurg ; : 1-9, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38579348

RESUMO

OBJECTIVE: This study aimed to investigate whether high homocysteine (Hcy) levels associated with the MTHFR gene influence the formation of the collateral vascular network in patients with moyamoya disease (MMD) after encephaloduroarteriosynangiosis (EDAS) by influencing the number of endothelial progenitor cells (EPCs) in peripheral blood. METHODS: A total of 118 Chinese patients with bilateral primary MMD were prospectively included. Blood samples were collected from the anterior cubital vein before surgery, and MTHFR rs9651118 was genotyped using high-throughput mass spectrometry to determine the genotype of the test specimen. Serum Hcy and EPC levels were measured, the latter with flow cytometry. Digital subtraction angiography was performed 6 months after EDAS, and the formation of collateral circulation was evaluated using the Matsushima grade system. The correlations between MTHFR rs9651118 genotype, Hcy and EPC levels, and Matsushima grade were compared. RESULTS: Among the 118 patients, 53 had the TT genotype (wild type) of MTHFR rs9651118, 33 TC genotype (heterozygous mutation), and 32 CC genotype (homozygous mutation). The mean ± SD Hcy level was 13.4 ± 9.5 µmol/L in TT patients, 9.8 ± 3.2 µmol/L in TC patients, and 8.9 ± 2.9 µmol/L in CC patients (p < 0.001). The level of EPCs in the venous blood of TT patients was 0.039% ± 0.016%, that of TC patients 0.088% ± 0.061%, and that of CC patients 0.103% ± 0.062% (p < 0.001). When the rs9651118 gene locus was mutated, Matsushima grade was better (p < 0.001) but there was no difference between heterozygous and homozygous mutations. CONCLUSIONS: The results suggest that the MTHFR rs9651118 polymorphism is a good biomarker for collateral vascular network formation after EDAS in MMD patients.

4.
Angew Chem Int Ed Engl ; : e202404730, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38618864

RESUMO

The anodic methanol oxidation reaction (MOR) plays a crucial role in coupling with the cathodic hydrogen evolution reaction (HER) and enables the sustainable production of the high-valued formate. Nickel-based hydroxide (Ni(OH)2) as MOR electrocatalyst has attracted enormous attention. However, the key factor determining the intrinsic catalytic activity remains unknown, which significantly hinders the further development of Ni(OH)2 electrocatalyst. Here, we found that the dx2-y2 electronic state within antibonding bands plays a decisive role in the whole MOR process. The onset potential depends on the deprotonation ability (Ni2+ to Ni3+), which was closely related to the band center of dx2-y2 orbital. The closer of dx2-y2 orbital to the Fermi level showed the stronger the deprotonation ability. Meanwhile, in the high potential region, the broadening of dx2-y2 orbital would facilitate the electron transfer from methanol to catalysts (Ni3+ to Ni2+), further enhancing the catalytic properties. Our work for the first time clarifies the intrinsic relationship between dx2-y2 electronic state and the MOR activities, which adds a new layer of understanding to the methanol electrooxidation research scene.

5.
Int J Colorectal Dis ; 39(1): 55, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38647724

RESUMO

BACKGROUND: Some Chinese scholars have initially explored the efficacy of electroacupuncture at Baliao acupoint in patients with functional anorectal pain (FAP). However, their studies are performed in a single center, or the sample size is small. Therefore, we aim to further explore the efficacy of electroacupuncture at Baliao acupoint on the treatment of FAP. METHODS: In this multicenter randomized controlled trial, 136 eligible FAP patients will be randomly allocated into an electroacupuncture group or sham electroacupuncture group at a 1:1 ratio. This trial will last for 34 weeks, with 2 weeks of baseline, 4 weeks and 8 weeks of treatment, and 1, 3, and 6 months of follow-up. Outcome assessors and statisticians will be blind. The primary outcome will be clinical treatment efficacy, and secondary outcomes will be pain days per month, quality of life, psychological state assessment, anorectal manometry, pelvic floor electromyography, and patient satisfaction. DISCUSSION: Results of this trial will be contributed to further clarify the value of electroacupuncture at Baliao acupoint as a treatment for FAP in the clinic. TRIAL REGISTRATION: This trial has been registered in Chinese Clinical Trial Registry  https://www.chictr.org.cn/  (ChiCTR2300069757) on March 24, 2023.

6.
ACS Omega ; 9(11): 13469-13480, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38524438

RESUMO

Hydraulic fracturing technology is the main method to develop low-permeability reservoirs. Fracture conductivity is not only the basis of fracture optimization design but also one of the key parameters to determine the effect of hydraulic fracturing. However, current methods of calculating fracture conductivity require a lot of time and labor cost. This research proposes a fracture conductivity prediction model based on machine learning. The main controlling factors of fracture conductivity are determined using the Pearson coefficient method and gray correlation analysis. Example application shows that the R2 values of the BP neural network model based on a genetic algorithm for predicting the fracture conductivity of block A and block B are 0.981 and 0.975, respectively, indicating that the machine learning model can accurately predict fracture conductivity.

7.
Aging (Albany NY) ; 16(5): 4579-4590, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38428404

RESUMO

Osteosarcoma is a cancer originating in the bone cells, specifically in the osteoblasts. Previous studies mainly focused on particular molecules but the whole pathway network. We comprehensively analyzed the enrichment score of each signal pathway and identified a novel classification by 20 machine learning algorithms. Furthermore, differences in tumor immune infiltration cells and drug sensitivity were compared in low and high groups. We identified a model consisting of four signaling pathways that predict the prognosis and the immune status of the tumor microenvironment and drug sensitivity in osteosarcoma patients. The novel classification may be used in clinical applications to predict prognosis and drug sensitivity.


Assuntos
Neoplasias Ósseas , Osteossarcoma , Humanos , Osteossarcoma/tratamento farmacológico , Osteossarcoma/genética , Osteoblastos , Prognóstico , Algoritmos , Microambiente Tumoral/genética , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/genética
8.
Heliyon ; 10(5): e26553, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38455558

RESUMO

Objective: The study aims to evaluate and compare the efficacy and safety between ticagrelor and clopidogrel in acute coronary syndrome (ACS) patients undergoing percutaneous coronary intervention (PCI). Methods: We searched MEDLINE (via PubMed), Cochrane, Embase, and the Cochrane library databases for eligible citations (the last search was up to December 2021). Subgroup analyses were performed based on region, study design, dose, and single-center/multicenter. Meta regressions were conducted to explore the source of heterogeneity. A sensitivity analysis was conducted to assess the robustness of the results. Funnel plots and Egger's test were preformed to test publication bias of the meta-analysis. Results: A total of 29 studies were included, totaling 165,981 patients. Ticagrelor reduced the overall incidence rate of major adverse cardiovascular events (MACEs) (HR 0.74; 95% CI, 0.62, 0.89; P = 0.001; I2 = 88.3%, P < 0.001) and all-cause mortality (HR 0.85; 95% CI, 0.75, 0.97; P = 0.019; I2 = 39.7%, P = 0.052) compared with clopidogrel. However, there was a higher risk of major bleeding (HR 1.21; 95% CI, 1.02,1.44; P = 0.026, I2 = 59.3%, P = 0.012) and all bleeding (HR 1.42; 95% CI, 1.24, 1.62; P < 0.001, I2 = 76.4%, P < 0.001) with ticagrelor compared to clopidogrel. The stability of the results was demonstrated by sensitivity analysis. Furthermore, subgroup analyses and meta-regression revealed that the heterogeneity in the study may stem from factors such as whether it was conducted in a single-center or multicenter setting, as well as the geographical region. Conclusion: Ticagrelor has demonstrated superior efficacy compared to clopidogrel in ACS patients undergoing PCI, particularly in Asia and Europe. Nevertheless, it is crucial to acknowledge that the utilization of ticagrelor is linked to a heightened risk of bleeding. To provide guidance for clinical decision-making regarding the use of ticagrelor, future multicenter randomized trials that are relevant and encompass longer follow-up periods are necessary. The category of the manuscript a meta-analysis: PROSPERO registration number CRD42021274198.

9.
Stroke Vasc Neurol ; 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38460971

RESUMO

BACKGROUND: The relationship between anterior cerebral artery (ACA) occlusion and moyamoya disease (MMD) has rarely been studied. In this study, we focused on a special type of MMD: isolated ACA-occlusive MMD. We investigated clinical attributes, genotypes and progression risk factors in patients with ACA-occlusive MMD, providing initial insights into the relationship between ACA occlusion and MMD. METHODS: We retrospectively analysed digital subtraction angiography (DSA) from 2486 patients and diagnosed 139 patients with ACA-occlusive MMD. RNF213 p.R4810K (rs112735431) mutation analysis was performed. Patients were categorised into progression and non-progression groups based on whether they progressed to typical MMD. Differences in clinical characteristics, neuropsychological assessment, radiological findings and genotypes were evaluated. Logistic regression analyses identified risk factors for ACA-occlusive MMD progression. RESULTS: The median age of patients with ACA-occlusive MMD was 36 years, and the primary symptom was transient ischaemic attack (TIA). 72.3% of ACA-occlusive MMD patients had cognitive decline. Of 116 patients who underwent RNF213 gene mutation analysis, 90 patients (77.6%) carried the RNF213 p.R4810K GG allele and 26 (22.4%) carried the GA allele. Of 102 patients with follow-up DSA data, 40 patients (39.2%) progressed. Kaplan-Meier curve estimates indicated a higher incidence of ischaemic stroke in the progression group during follow-up (p=0.035). Younger age (p=0.041), RNF213 p.R4810K GA genotype (p=0.037) and poor collateral compensation from the middle cerebral artery (MCA) to ACA (p<0.001) were risk factors of ACA-occlusive MMD progression to typical MMD. CONCLUSIONS: Cognitive decline and TIA might be the main manifestations of ACA-occlusive MMD. Isolated ACA occlusion may be an early signal of MMD. The initial lesion site of MMD is not strictly confined to the terminal portion of the internal carotid artery. Younger patients, patients with RNF213 p.R4810K GA genotype or those with inadequate MCA-to-ACA compensation are more likely to develop typical MMD.

10.
Sci Total Environ ; 925: 171762, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38508270

RESUMO

Ores serve as energy and nutrient sources for microorganisms. Through complex biochemical processes, microorganisms disrupt the surface structure of ores and release metal elements. However, there is limited research on the mechanisms by which bacteria with different nutritional modes act during the leaching process of different crystal structure ores. This study evaluated the leaching efficiency of two types of bacteria with different nutritional modes, heterotrophic bacterium Bacillus mucilaginosus (BM) and autotrophic bacterium Acidithiobacillus ferrooxidans (AF), on different crystal structure lithium silicate ores (chain spodumene, layered lepidolite and ring elbaite). The aim was to understand the behavioral differences and decomposition mechanisms of bacteria with different nutritional modes in the process of breaking down distorted crystal lattices of ores. The results revealed that heterotrophic bacterium BM primarily relied on passive processes such as bacterial adsorption, organic acid corrosion, and the complexation of small organic acids and large molecular polymers with metal ions. Autotrophic bacterium AF, in addition to exhibiting stronger passive processes such as organic acid corrosion and complexation, also utilized an active transfer process on the cell surface to oxidize Fe2+ in the ores for energy maintenance and intensified the destruction of ore lattices. As a result, strain AF exhibited a greater leaching effect on the ores compared to strain BM. Regarding the three crystal structure ores, their different stacking modes and proportions of elements led to significant differences in structural stability, with the leaching effect being highest for layered structure, followed by chain structure, and then ring structure. These findings indicate that bacteria with different nutritional modes exhibit distinct physiological behaviors related to their nutritional and energy requirements, ultimately resulting in different sequences and mechanisms of metal ion release from ores after lattice damage.


Assuntos
Acidithiobacillus , Bactérias , Lítio , Bactérias/metabolismo , Metais/metabolismo , Silicatos/química , Íons
11.
Exp Cell Res ; 437(1): 113994, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38479704

RESUMO

m6A modification has been studied in tumors, but its role in host anti-tumor immune response and TAMs polarization remains unclear. The fatty acid oxidation (FAO) process of TAMs is also attracting attention. A co-culture model of colorectal cancer (CRC) cells and macrophages was used to simulate the tumor microenvironment. Expression changes of m6A demethylase genes FTO and ALKBH5 were screened. ALKBH5 was further investigated. Gain-of-function experiments were conducted to study ALKBH5's effects on macrophage M2 polarization, CRC cell viability, proliferation, migration, and more. Me-RIP and Actinomycin D assays were performed to study ALKBH5's influence on CPT1A, the FAO rate-limiting enzyme. AMP, ADP, and ATP content detection, OCR measurement, and ECAR measurement were used to explore ALKBH5's impact on macrophage FAO level. Rescue experiments validated ALKBH5's mechanistic role in macrophage M2 polarization and CRC malignant development. In co-culture, CRC cells enhance macrophage FAO and suppress m6A modification in M2 macrophages. ALKBH5 was selected as the gene for further investigation. ALKBH5 mediates CPT1A upregulation by removing m6A modification, promoting M2 macrophage polarization and facilitating CRC development. These findings indicate that ALKBH5 enhances fatty acid metabolism and M2 polarization of macrophages by upregulating CPT1A, thereby promoting CRC development.


Assuntos
Neoplasias Colorretais , Macrófagos , Humanos , Regulação para Cima/genética , Macrófagos/metabolismo , Neoplasias Colorretais/patologia , Ácidos Graxos/metabolismo , Microambiente Tumoral , Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , Homólogo AlkB 5 da RNA Desmetilase/genética , Homólogo AlkB 5 da RNA Desmetilase/metabolismo
12.
ACS Omega ; 9(11): 12789-12800, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38524481

RESUMO

The current research on fracture conductivity ignores the placement of the proppant in fractures and relies on single-fracture conductivity testing and calculation, which cannot represent the overall conductivity of complex fracture systems. This research proposes a calculation method for the long-term conductivity of complex fractures based on proppant placement. This method considers fracture morphology, proppant placement, proppant embedment, and deformation under high closing pressure. The research results show that fracture conductivity decreases with increasing time, which can be divided into three stages: the embedding stage, the creep stage, and the stabilization stage. The long-term conductivity of the main fracture is higher than that of the branching fracture. With increasing closing pressure, the conductivities of both the main fracture and the branching fracture decrease. This is because increasing closure stress accelerates proppant embedment and creep, compressing the fluid flow space and further reducing fracture conductivity. Fracture conductivity is related to the placement of the proppant and sand concentration. Increasing the sand ratio can significantly increase the placement of the proppant in the main fracture and branching fractures, thereby improving fracture conductivity. Increasing the fracturing fluid viscosity can increase its proppant migration capacity. The proppant does not easily settle prematurely in high-viscosity fracturing fluid and can enter more into branching fractures, thereby improving their conductivity.

13.
J Inflamm Res ; 17: 1721-1733, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38523687

RESUMO

Background: The immune system plays an important role in the onset and development of moyamoya disease (MMD), but the specific mechanisms remain unclear. This study aimed to explore the relationship between the expression of complements and immunoglobulin in serum and progression of MMD. Methods: A total of 84 patients with MMD and 70 healthy individuals were enrolled. Serum immunoglobulin and complement C3 and C4 expression were compared between healthy individuals and MMD patients. Follow-up was performed at least 6 months post-operation. Univariate and multivariate analysis after adjusting different covariates were performed to explore predictive factors associated with vasculopathy progression. A nomogram basing on the results of multivariate analysis was established to predict vasculopathy progression. Results: Compared to healthy individuals, MMD patients had significantly lower expression of serum complements C3 (P = 0.003*). Among MMD patients, C3 was significantly lower in those with late-stage disease (P = 0.001*). Of 84 patients, 27/84 (32.1%) patients presented with vasculopathy progression within a median follow-up time of 13.0 months. Age (P=0.006*), diastolic blood pressure (P=0.004*) and serum complement C3 expression (P=0.015*) were associated with vasculopathy progression after adjusting different covariables. Conclusion: Complement C3 is downregulated in moyamoya disease and decreases even further in late-Suzuki stage disease. Age, diastolic blood pressure and serum complement C3 expression are associated with vasculopathy progression, suggesting that the complement might be involved in the development of moyamoya disease.

14.
Heliyon ; 10(4): e26108, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38404780

RESUMO

Objective: This study aimed to explore the long-term outcome of unilateral moyamoya disease and predict the clinical and genetic factors associated with contralateral progression in unilateral moyamoya disease. Methods: We retrospectively recruited unilateral moyamoya disease patients with available genetic data who underwent encephaloduroarteriosynangiosis (EDAS) surgery at our institution from January 2009 to November 2017. Long-term follow-up data, including clinical outcomes, angiographic features, and genetic information, were analyzed. Results: A total of 83 unilateral moyamoya disease patients with available genetic data were enrolled in our study. The mean duration of clinical follow-up was 7.9 ± 2.0 years. Among all patients, 19 patients demonstrated contralateral progression to bilateral disease. Heterozygous Ring Finger Protein 213 p.R4810K mutations occurred significantly more frequently in unilateral moyamoya disease patients with contralateral progression. Furthermore, patients with contralateral progression typically demonstrated an earlier age of onset than those with non-progressing unilateral moyamoya disease. In the contralateral progression group, posterior circulation involvement was observed in 11 (11/19, 57.9%) patients compared to 12 (12/64, 18.8%) in the non-contralateral progression group (P = 0.001). The time to peak of cerebral perfusion and neurological status showed significant postoperative improvement. Conclusion: Long-term follow-up revealed that the EDAS procedure might provide benefits for unilateral moyamoya disease patients. Ring Finger Protein 213 p.R4810K mutations, younger age, and posterior circulation involvement might predict the contralateral progression of unilateral moyamoya disease.

15.
Nat Commun ; 15(1): 1383, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38360821

RESUMO

Cobalt oxyhydroxide (CoOOH) is a promising catalytic material for oxygen evolution reaction (OER). In the traditional CoOOH structure, Co3+ exhibits a low-spin state configuration ([Formula: see text]), with electron transfer occurring in face-to-face [Formula: see text] orbitals. In this work, we report the successful synthesis of high-spin state Co3+ CoOOH structure, by introducing coordinatively unsaturated Co atoms. As compared to the low-spin state CoOOH, electron transfer in the high-spin state CoOOH occurs in apex-to-apex [Formula: see text] orbitals, which exhibits faster electron transfer ability. As a result, the high-spin state CoOOH performs superior OER activity with an overpotential of 226 mV at 10 mA cm-2, which is 148 mV lower than that of the low-spin state CoOOH. This work emphasizes the effect of the spin state of Co3+ on OER activity of CoOOH based electrocatalysts for water splitting, and thus provides a new strategy for designing highly efficient electrocatalysts.

16.
Phytomedicine ; 126: 155203, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38387277

RESUMO

BACKGROUND: Slow transit constipation (STC) is a common gastrointestinal disorder that is often accompanied by depression. Nobiletin is a natural compound that has been shown to have anti-inflammatory and anti-depressant effects. PURPOSE: To study the effects of nobiletin extracted from Wenyang Yiqi Formula 19 (WYF) on STC accompanied by depression and the related mechanism in STC mouse models. METHODS: In this study, the effects of nobiletin on STC accompanied by depression were investigated in both an STC animal model and an in vitro study. The animal model was induced by loperamide, and the in vitro study used Interstitial cells of Cajal (ICCs) isolated from STC mice. The efficacy of nobiletin was assessed by comparing various parameters, including stool particle counts, moisture content, intestinal propulsive rate, colon histopathology, microtubule-associated protein-tau (MAPT) expression in colon tissue, serum levels of TNF-α, IL-1ß, IL-6, IFN-γ, and the levels of MAPK pathway-related proteins among three experimental groups. RESULTS: Nobiletin treatment significantly improved stool particle counts, moisture content, intestinal propulsive rate, and colon histopathology in the STC animal model. Nobiletin also decreased MAPT expression in colon tissue and serum levels of TNF-α, IL-1ß, IL-6, IFN-γ, and the levels of MAPK pathway-related proteins. In the in vitro study, nobiletin treatment reversed the increased cell proliferation and cell apoptosis observed in ICC isolated from the STC model. CONCLUSION: The findings of this study indicate that nobiletin exhibits promising therapeutic potential in addressing STC accompanied by depression. This potential may be attributed to its ability to regulate the function of ICC by targeting MAPT.


Assuntos
Depressão , Flavonas , Interleucina-6 , Camundongos , Animais , Depressão/tratamento farmacológico , Fator de Necrose Tumoral alfa , Constipação Intestinal/tratamento farmacológico , Transdução de Sinais , Modelos Animais de Doenças , Trânsito Gastrointestinal/fisiologia
17.
Sci Total Environ ; 921: 171166, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38401738

RESUMO

Typhoons are recognized as one of the most destructive meteorological phenomena, exerting significant influences on marine ecosystems. Sea surface chlorophyll-a concentration (CHL)an essential indicator of phytoplankton biomass, can be utilized to characterize the disturbances of typhoons on the marine ecosystem. However, it is challenging to investigate this impact at a daily scale due to the missing CHL remote sensing data caused by cloud cover. Given that concurrent passing typhoons may interact with CHL, this study analyzes the effect of the simultaneous passage of binary typhoons Tembin and Bolaven on CHL by using daily CHL reconstruction data, and investigates the role of ocean environmental factors in driving the dynamics of CHL, including sea surface temperature (SST), mixed layer depth (MLD), and sea surface height anomaly (SSHA). The results show that typhoons Tembin and Bolaven increase CHL with the maximum increment of ∼3.2 mg∙m-3 during 4-6 days after typhoons passage. The maximum change areas of CHL are distributed near the intersection of typhoon track of (32°N, 125.2°E), corresponding to the regions of greater variation in SST and MLD. During 15 days before and after typhoons (i.e., from 15 August to 15 September 2012), SST is negatively correlated with CHL (the correlation coefficient of -0.85) and MLD is positively correlated with CHL (the correlation coefficient of -0.80). SST immediately declines after typhoons with a maximum cooling of 7.8 deg. C, showing the decreased SST from ∼28 deg. C to ∼23 deg. C can promote phytoplankton growth. MLD deepens from 10 m to >25 m caused by typhoon-induced strong winds, allowing more nutrients to be transported from the subsurface layer to the euphotic layer for phytoplankton blooms. Furthermore, oceanic eddies captured by SSHA change from cyclonic to anticyclonic eddies accompanied by the beginning of CHL increases, and the largest CHL increases correspond to the distribution of pre-existing cyclonic eddies. It suggests that Tembin and Boravin promote phytoplankton growth to increase CHL by enhancing vertical mixing and upwelling to transport nutrients to the sea surface. These findings inspire us to rethink the daily effects of typhoons on CHL, with critical importance for predicting and managing the ecological consequences of typhoons in the ocean.


Assuntos
Tempestades Ciclônicas , Ecossistema , Clorofila A , Clorofila , Oceanos e Mares , Fitoplâncton , Estações do Ano
18.
Eur J Pharmacol ; 967: 176402, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38331339

RESUMO

OBJECTIVE: To investigate whether pentoxifylline (PTX) attenuates cerebral ischaemia-reperfusion injury (IRI) in rats by inhibiting ferroptosis and to explore the underlying molecular mechanisms. METHODS: Cerebral IRI was induced in male Sprague-Dawley (SD) rats using middle cerebral artery occlusion (MCAO). The effects of PTX on cerebral ischaemia-reperfusion brain samples were detected through neurological deficit score, staining and electron microscopy; levels of ferroptosis biomarkers from brain samples were detected using kits. Additionally, the expression levels of nuclear factor erythroid 2-related factor 2 (Nrf2), transferrin receptor protein 1, divalent metal transporter 1, solute carrier family 7 member 11 (SLC7A11) and glutathione peroxidase 4 (GPX4) were determined by immunohistochemistry, real-time quantitative polymerase chain reaction and western blotting. RESULTS: Pre-treatment with PTX was found to improve neurological function, evidenced by reduced neurological deficit scores, decreased infarct volume and alleviated pathological features post-MCAO. This improvement was accompanied by reduced lipid peroxidation levels and mitigated mitochondrial damage. Notably, PTX's inhibitory effect on ferroptosis was characterised by enhanced Nrf2 nuclear translocation and regulation of ferroptosis-related proteins. Moreover, inhibition of Nrf2 using ML385 (an Nrf2-specific inhibitor) reversed PTX's neuroprotective effect on MCAO-induced ferroptosis via the SLC7A11/GPX4 signalling pathway. CONCLUSIONS: Ferroptosis is evident following cerebral ischaemia-reperfusion in rats. Pentoxifylline confers protection against IRI in rats by inhibiting ferroptosis through the Nrf2/SLC7A11/GPX4 signalling pathway.


Assuntos
Ferroptose , Pentoxifilina , Traumatismo por Reperfusão , Masculino , Animais , Ratos , Ratos Sprague-Dawley , Pentoxifilina/farmacologia , Pentoxifilina/uso terapêutico , Fator 2 Relacionado a NF-E2 , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/prevenção & controle , Infarto Cerebral
19.
Pediatr Neurol ; 153: 159-165, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38394830

RESUMO

BACKGROUND: To explore the risk factors for preoperative massive cerebral infarction (MCI) in pediatric patients with moyamoya disease (MMD). METHODS: Pediatric patients with MMD treated between 2017 and 2022 were enrolled. Logistic regression analysis was performed to identify risk factors for MCI among the patients, and a nomogram was constructed to identify potential predictors of MCI. Receiver operating characteristic (ROC) curves and areas under the curves were calculated to determine the effects of different risk factors. RESULTS: This study included 308 pediatric patients with MMD, including 36 with MCI. The MCI group exhibited an earlier age of onset than the non-MCI group. Significant intergroup differences were observed in familial MMD history, postcirculation involvement, duration from diagnosis to initiation of treatment, Suzuki stage, magnetic resonance angiography (MRA) score, collateral circulation score, and RNF213 p.R4810K variations. Family history, higher MRA score, lower collateral circulation score, and RNF213 p.R4810K variations were substantial risk factors for MCI in pediatric patients with MMD. The nomogram demonstrated excellent discrimination and calibration capabilities. The integrated ROC model, which included all the abovementioned four variables, showed superior diagnostic precision with a sensitivity of 67.86%, specificity of 87.01%, and accuracy of 85.11%. CONCLUSIONS: This study showed that family history, elevated MRA score, reduced collateral circulation score, and RNF213 p.R4810K variations are risk factors for MCI in pediatric patients with MMD. The synthesized model including these variables demonstrated superior predictive efficacy; thus, it can facilitate early identification of at-risk patients and timely initiation of appropriate interventions.


Assuntos
Doença de Moyamoya , Humanos , Criança , Doença de Moyamoya/complicações , Doença de Moyamoya/diagnóstico por imagem , Predisposição Genética para Doença , Adenosina Trifosfatases , Ubiquitina-Proteína Ligases/genética , Infarto Cerebral/diagnóstico por imagem , Infarto Cerebral/etiologia , Fatores de Risco
20.
Inflamm Res ; 73(3): 459-473, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38286859

RESUMO

OBJECTIVE: Sepsis and sepsis-associated organ failure are devastating conditions for which there are no effective therapeutic agent. Several studies have demonstrated the significance of ferroptosis in sepsis. The study aimed to identify ferroptosis-related genes (FRGs) in sepsis, providing potential therapeutic targets. METHODS: The weighted gene co-expression network analysis (WGCNA) was utilized to screen sepsis-associated genes. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were used to explore gene functions. Three machine learning methods were employed to identify sepsis-related hub genes. Survival and multivariate Cox regression analysis allowed further screening for the key gene RRM2 associated with prognosis. The immune infiltration analysis of the screened sepsis key genes was performed. Additionally, a cecum ligation and puncture (CLP)-induced mouse sepsis model was constructed to validate the expression of key gene in the sepsis. RESULTS: Six sepsis-associated differentially expressed FRGs (RRM2, RPL7A, HNRNPA1, PEBP1, MYL8B and TXNIP) were screened by WGCNA and three machine learning methods analysis. Survival analysis and multivariate Cox regression analysis showed that RRM2 was a key gene in sepsis and an independent prognostic factor associated with clinicopathological and molecular features of sepsis. Immune cell infiltration analysis demonstrated that RRM2 had a connection to various immune cells, such as CD4 T cells and neutrophils. Furthermore, animal experiment demonstrated that RRM2 was highly expressed in CLP-induced septic mice, and the use of Fer-1 significantly inhibited RRM2 expression, inhibited serum inflammatory factor TNF-α, IL-6 and IL-1ß expression, ameliorated intestinal injury and improved survival in septic mice. CONCLUSION: RRM2 plays an important role in sepsis and may contribute to sepsis through the ferroptosis pathway. This study provides potential therapeutic targets for sepsis.


Assuntos
Ferroptose , Ribonucleosídeo Difosfato Redutase , Sepse , Animais , Camundongos , Linfócitos T CD4-Positivos , Ceco , Modelos Animais de Doenças , Ferroptose/genética , Sepse/genética , Fator de Necrose Tumoral alfa , Ribonucleosídeo Difosfato Redutase/metabolismo
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