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1.
J Biol Chem ; 300(1): 105518, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38042489

RESUMO

Bacillus Calmette-Guérin (BCG) vaccination induces a type of immune memory known as "trained immunity", characterized by the immunometabolic and epigenetic changes in innate immune cells. However, the molecular mechanism underlying the strategies for inducing and/or boosting trained immunity in alveolar macrophages remains unknown. Here, we found that mucosal vaccination with the recombinant strain rBCGPPE27 significantly augmented the trained immune response in mice, facilitating a superior protective response against Mycobacterium tuberculosis and non-related bacterial reinfection in mice when compared to BCG. Mucosal immunization with rBCGPPE27 enhanced innate cytokine production by alveolar macrophages associated with promoted glycolytic metabolism, typical of trained immunity. Deficiency of the mammalian target of rapamycin complex 2 and hexokinase 1 abolished the immunometabolic and epigenetic rewiring in mouse alveolar macrophages after mucosal rBCGPPE27 vaccination. Most noteworthy, utilizing rBCGPPE27's higher-up trained effects: The single mucosal immunization with rBCGPPE27-adjuvanted coronavirus disease (CoV-2) vaccine raised the rapid development of virus-specific immunoglobulin G antibodies, boosted pseudovirus neutralizing antibodies, and augmented T helper type 1-biased cytokine release by vaccine-specific T cells, compared to BCG/CoV-2 vaccine. These findings revealed that mucosal recombinant BCG vaccine induces lung-resident memory macrophages and enhances trained immunity via reprogramming mTORC2- and HK-1-mediated aerobic glycolysis, providing new vaccine strategies for improving tuberculosis (TB) or coronavirus variant vaccinations, and targeting innate immunity via mucosal surfaces.


Assuntos
Vacina BCG , Hexoquinase , Memória Imunológica , Pulmão , Macrófagos Alveolares , Alvo Mecanístico do Complexo 2 de Rapamicina , Mycobacterium tuberculosis , Imunidade Treinada , Animais , Camundongos , Vacina BCG/imunologia , Citocinas/metabolismo , Pulmão/imunologia , Macrófagos Alveolares/imunologia , Mycobacterium tuberculosis/imunologia , Vacinas Sintéticas/imunologia , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Hexoquinase/metabolismo
2.
Brief Bioinform ; 24(3)2023 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-37013942

RESUMO

Identifying protein-protein interaction (PPI) site is an important step in understanding biological activity, apprehending pathological mechanism and designing novel drugs. Developing reliable computational methods for predicting PPI site as screening tools contributes to reduce lots of time and expensive costs for conventional experiments, but how to improve the accuracy is still challenging. We propose a PPI site predictor, called Augmented Graph Attention Network Protein-Protein Interacting Site (AGAT-PPIS), based on AGAT with initial residual and identity mapping, in which eight AGAT layers are connected to mine node embedding representation deeply. AGAT is our augmented version of graph attention network, with added edge features. Besides, extra node features and edge features are introduced to provide more structural information and increase the translation and rotation invariance of the model. On the benchmark test set, AGAT-PPIS significantly surpasses the state-of-the-art method by 8% in Accuracy, 17.1% in Precision, 11.8% in F1-score, 15.1% in Matthews Correlation Coefficient (MCC), 8.1% in Area Under the Receiver Operating Characteristic curve (AUROC), 14.5% in Area Under the Precision-Recall curve (AUPRC), respectively.


Assuntos
Mapeamento de Interação de Proteínas , Inibidores da Bomba de Prótons , Mapeamento de Interação de Proteínas/métodos , Proteínas/química , Área Sob a Curva , Curva ROC
3.
Anal Chem ; 96(1): 581-589, 2024 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-38150390

RESUMO

Although near-infrared responsive photoelectrochemical (PEC) biosensors have less damage to biological components compared to UV-visible light, they still reveal an inferior response due to the rapid recombination of photogenerated electron-hole. In this study, a near-infrared-driven PEC biosensor is fabricated for microRNA (miRNA) detection via integrating photoelectricity and pyroelectricity. Upon the introduction of target miRNA-21, the exponential DNA amplifier is triggered based on enzyme-assisted strand displacement amplification (SDA), releasing multiple Ag2S reporter probes to hybridize with capture probes immobilized on a CdS-2-mercaptobenzimidazole (2MBI)-modified photoelectrode. As a result, under the stimulation of NIR, the photoelectric conversion of Ag2S NPs generates the photocurrents. In addition, due to the strong hole acceptor ability of MBI, the pyroelectric effect of CdS-2MBI nanocomposites is enhanced, which generates highly pyroelectro-induced charge separation efficiency and induces the pyroelectric current benefited from the spontaneous polarization of CdS-2MBI caused by the temperature variation under the function of Ag2S nanoheaters. Impressively, this PEC biosensor has achieved the sensitive and selective determination of miRNA-21 with a detection limit as low as 54 fM. Overall, this NIR-driven PEC biosensor based on pyroelectric and photoelectric effects opens up a new horizon for bioanalysis and early disease diagnosis.


Assuntos
Técnicas Biossensoriais , MicroRNAs , Nanocompostos , MicroRNAs/análise , DNA , Luz , Técnicas Eletroquímicas , Limite de Detecção
4.
Small ; 20(11): e2306510, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37880878

RESUMO

Soft millirobots have evolved into various therapeutic applications in the medical field, including for vascular dredging, cell transportation, and drug delivery, owing to adaptability to their surroundings. However, most soft millirobots cannot quickly enter, retrieve, and maintain operations in their original locations after removing the external actuation field. This study introduces a soft magnetic millirobot for targeted medicine delivery that can be transported into the body through a catheter and anchored to the tissues. The millirobot has a bilayer adhesive body with a mussel-inspired hydrogel layer and an octopus-inspired magnetic structural layer. It completes entry and retrieval with the assistance of a medical catheter based on the difference between the adhesion of the hydrogel layer in air and water. The millirobot can operate in multiple modes of motion under external magnetic fields and underwater tissue adhesion after self-unfolding with the structural layer. The adaptability and recyclability of the millirobots are demonstrated using a stomach model. Combined with ultrasound (US) imaging, operational feasibility within organisms is shown in isolated small intestines. In addition, a highly efficient targeted drug delivery is confirmed using a fluorescence imaging system. Therefore, the proposed soft magnetic millirobots have significant potential for medical applications.


Assuntos
Adesivos , Sistemas de Liberação de Medicamentos , Hidrogéis/química , Catéteres , Fenômenos Magnéticos
5.
Small ; 20(34): e2308858, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38618927

RESUMO

Although TiNb2O7 (TNO) with comparable operating potential and ideal theoretical capacity is considered to be the most ideal replacement for negative Li4Ti5O12 (LTO), the low ionic and electronic conductivity still limit its practical application as satisfactory anode for lithium-ion batteries (LIBs) with high-power density. Herein, TNO nanoparticles modified by Cerium (Ce) with outstanding electrochemical performance are synthesized. The successful introduction of Ce3+ in the lattice leads to increased interplanar spacing, refined grain size, more oxygen vacancy, and a smaller lithium diffusion barrier, which are conducive to improve conductivity of both Li+ and electrons. As a result, the modified TNO reaches high reversible capacity of 256.0 mA h g-1 at 100 mA g-1 after 100 cycles, and 183.0 mA h g-1 even under 3200 mA g-1. In particular, when the temperature drops to -20 °C, the cell undergoing 1500 cycles at a high current density of 500 mA g-1 can still reach 89.7 mA h g-1, corresponding to a capacity decay rate per cycle of only 0.033%. This work provides a new way to improve the electrochemical properties of alternative anodes for LIBs at extreme temperature.

6.
Artigo em Inglês | MEDLINE | ID: mdl-39212726

RESUMO

Behaviors and auditory physiological responses of some species of echolocating bats remain unaffected after exposure to intense noise, but information on the underlying mechanisms remains limited. Here, we studied whether the vocalization-induced middle ear muscle (MEM) contractions (MEM reflex) and auditory fovea contributed to the unimpaired auditory sensitivity of constant frequency-frequency modulation (CF-FM) bats after exposure to broad-band intense noise. The vocalizations of the CF-FM bat, Hipposideros pratti, were inhibited through anesthesia to eliminate the vocalization-induced MEM reflex. First, the anesthetized bats were exposed to intense broad-band noise, and the findings showed that the bats could still maintain their auditory sensitivities. However, auditory sensitivities were seriously impaired in CBA/Ca mice exposed to intense noise under anesthesia. This indicated that the unimpaired auditory sensitivity in H. pratti after exposure to intense noise under anesthesia was not due to anesthetization. The bats were further exposed to low-frequency band-limited noise, whose passband did not overlap with echolocation call frequencies. The results showed that the auditory responses to sound frequencies within the noise spectrum and one-half octave higher than the spectrum were also unimpaired. Taken together, the results indicate that both vocalization-induced MEM reflex and auditory fovea do not contribute to the unimpaired auditory sensitivity in H. pratti after exposure to intense noise. The possible mechanisms underlying the unimpaired auditory sensitivity after echolocating bats were exposed to intense noise are discussed.

7.
Inflamm Res ; 73(4): 485-498, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38467875

RESUMO

OBJECTIVE: This study aims to elucidate the role of T follicular helper (Tfh) cells and their subsets in idiopathic membranous nephropathy (IMN). METHODS: The frequencies of Tfh cell subsets and B cell subsets in peripheral blood (PB) were detected in both IMN patients and healthy controls (HCs). The involvement of Tfh cells in the disease pathogenesis was examined by coculturing human Tfh cells with B cells. The dynamic changes of Tfh cells in PB or spleen were monitored in passive Heymann nephritis (PHN) rats. RESULTS: The frequencies of circulating Tfh (cTfh) cells, cTfh2 cells, and plasmablasts were enriched in the PB of patients with IMN. cTfh cells expressed higher ICOS, and lower BTLA than healthy counterparts. The frequency of ICOS + cTfh2 was associated with the severity of IMN, including 24h urine protein, IgG4 concentration and the IgG4: IgG ratio. Positive correlations were also observed between the frequency of cTfh2 cells with plasmablasts, serum IL-21 and IL-4 levels. Importantly, cTfh cells isolated from IMN patients were able to induce the differentiation of B cells to memory B cells (MBC) and plasmablasts, this process could be substantially attenuated by blocking the IL-21. Similar increases of ICOS + cTfh cells were also detected in spleen of PHN rats, concomitant with elevated urine protein levels. CONCLUSIONS: Collectively, our results demonstrate that the imbalance of cTfh cell subsets play a crucial pathogenic role in IMN by inducing the differentiation of B cells through IL-21, and cTfh2 cells might serve as useful markers to evaluate the progression of IMN.


Assuntos
Glomerulonefrite Membranosa , Células T Auxiliares Foliculares , Humanos , Animais , Ratos , Células T Auxiliares Foliculares/metabolismo , Linfócitos T Auxiliares-Indutores/metabolismo , Glomerulonefrite Membranosa/metabolismo , Linfócitos B , Imunoglobulina G
8.
Nanotechnology ; 35(24)2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38478979

RESUMO

In the realm of molecular detection, the surface-enhanced Raman scattering (SERS) technique has garnered increasing attention due to its rapid detection, high sensitivity, and non-destructive characteristics. However, conventional rigid SERS substrates are either costly to fabricate and challenging to prepare over a large area, or they exhibit poor uniformity and repeatability, making them unsuitable for inspecting curved object surfaces. In this work, we present a flexible SERS substrate with high sensitivity as well as good uniformity and repeatability. First, the flexible polydimethylsiloxane (PDMS) substrate is manually formulated and cured. SiO2/Ag layer on the substrate can be obtained in a single process by using ion beam sputtering. Then, reactive ion etching is used to etch the upper SiO2layer of the film, which directly leads to the desired densely packed nanostructure. Finally, a layer of precious metal is deposited on the densely packed nanostructure by thermal evaporation. In our proposed system, the densely packed nanostructure obtained by etching the SiO2layer directly determines the SERS ability of the substrate. The bottom layer of silver mirror can reflect the penetrative incident light, the spacer layer of SiO2and the top layer of silver thin film can further localize the light in the system, which can realize the excellent absorption of Raman laser light, thus enhancing SERS ability. In the tests, the prepared substrates show excellent SERS performance in detecting crystalline violet with a detection limit of 10-11M. The development of this SERS substrate is anticipated to offer a highly effective and convenient method for molecular substance detection.

9.
Nanotechnology ; 36(2)2024 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-39422553

RESUMO

Three-dimensional (3D) free-standing nanostructures based on electron-beam lithography (EBL) have potential applications in many fields with extremely high patterning resolution and design flexibility with direct writing. In numerous EBL processes designed for the creation of 3D structures, the multilayer resist system is pivotal due to its adaptability in design. Nevertheless, the compatibility of solvents between different layers of resists often restricts the variety of feasible multilayer combinations. This paper introduces an innovative approach to address the bottleneck issue by presenting a novel concept of multilayer resist dry stacking, which is facilitated by a near-zero adhesion strategy. The poly(methyl methacrylate) (PMMA) film is stacked onto the hydrogen silsesquioxane (HSQ) resist using a dry peel and release technique, effectively circumventing the issue of HSQ solubilization by PMMA solvents typically encountered during conventional spin-coating procedures. Simultaneously, a dry lift-off technique can be implemented by eschewing the use of organic solvents during the wet process. This pioneering method enables the fabrication of high-resolution 3D free-standing plasmonic nanostructures and intricate 3D free-standing nanostructures. Finally, this study presents a compelling proof of concept, showcasing the integration of 3D free-standing nanostructures, fabricated via the described technique, into the realm of Fabry-Perot cavity resonators, thereby highlighting their potential for practical applications. This approach is a promising candidate for arbitrary 3D free-standing nanostructure fabrication, which has potential applications in nanoplasmonics, nanoelectronics, and nanophotonics.

10.
J Biochem Mol Toxicol ; 38(1): e23615, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38084627

RESUMO

Circular RNA (circRNA) was an important modulator and potential molecular target of nonsmall cell lung cancer (NSCLC). CircSATB2 was reported to be upregulated in NSCLC. However, the role and mechanism of circSATB2 in NSCLC progression remain to be illustrated. The RNA and protein expression was detected by quantitative real-time polymerase chain reaction, western blot, and immunohistochemistry assay. Cell counting kit-8, cell colony formation, and 5-ethynyl-2'-deoxyuridine assays were applied to assess cell growth. The migrated and invaded cells were examined by transwell assay. Flow cytometry was performed to measure apoptotic cells. The interaction among circSATB2, microRNA-150-5p (miR-150-5p), and tripartite motif-containing protein 66 (TRIM66) was identified by dual-luciferase reporter assay and RNA immunoprecipitation assay. An in vivo experiment was conducted to investigate the effect of circSATB2 on tumor growth. CircSATB2 expression was highly expressed in NSCLC tissues and cell lines. CircSATB2 and TRIM66 silencing both suppressed NSCLC cell growth, migration, and invasion whereas promoted NSCLC cell apoptosis. CircSATB2 acted as a molecular sponge for miR-150-5p, and miR-150-5p interacted with the 3' untranslated region (3'UTR) of TRIM66. Moreover, circSATB2 knockdown-induced effects were partly reversed by TRIM66 overexpression in NSCLC cells. Besides, cirSATB2 expression was negatively correlated with miR-150-5p level and positively correlated with TRIM66 level in NSCLC tumor tissues. CircSATB2 knockdown blocked xenograft tumor growth in vivo. In summary, this study verified that circSATB2 stimulated NSCLC cell malignant behaviors by miR-150-5p/TRIM66 pathway, providing a possible circRNA-targeted therapy for NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Proteínas de Ligação à Região de Interação com a Matriz , MicroRNAs , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , RNA Endógeno Competitivo , RNA Circular/genética , Neoplasias Pulmonares/genética , Regiões 3' não Traduzidas , Proliferação de Células , MicroRNAs/genética , Linhagem Celular Tumoral , Fatores de Transcrição , Peptídeos e Proteínas de Sinalização Intracelular
11.
J Appl Toxicol ; 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38644760

RESUMO

Prolonged exposure to environments with high concentrations of crystalline silica (CS) can lead to silicosis. Macrophages play a crucial role in the pathogenesis of silicosis. In the process of silicosis, silica (SiO2) invades alveolar macrophages (AMs) and induces mitophagy which usually exists in three states: normal, excessive, and/or deficiency. Different mitophagy states lead to corresponding toxic responses, including successful macrophage repair, injury, necrosis, apoptosis, and even pulmonary fibrosis. This is a complex process accompanied by various cytokines. Unfortunately, the details have not been fully systematically summarized. Therefore, it is necessary to elucidate the role of macrophage mitophagy in SiO2-induced pulmonary fibrosis by systematic analysis on the literature reports. In this review, we first summarized the current data on the macrophage mitophagy in the development of SiO2-induced pulmonary fibrosis. Then, we introduce the molecular mechanism on how SiO2-induced mitophagy causes pulmonary fibrosis. Finally, we focus on introducing new therapies based on newly developed mitophagy-inducing strategies. We conclude that macrophage mitophagy plays a multifaceted role in the progression of SiO2-induced pulmonary fibrosis, and reprogramming the macrophage mitophagy state accordingly may be a potential means of preventing and treating pulmonary fibrosis.

12.
J Environ Manage ; 369: 122382, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39232326

RESUMO

The global attention towards waste management and valorization has led to significant interest in recovering valuable components from sludge incineration ash (SIA) for the synthesis of functional environmental materials. In this study, the SIA was converted to an S-doped Fe2+-zeolite type catalyst (FZA) for the treatment of emerging contaminants (ECs), exemplified by sulfamethoxazole (SMX). Results demonstrate that FZA effectively catalyzed the activation of peracetic acid (PAA), achieving a remarkable degradation of 99.8% under optimized conditions. Mechanistic investigations reveal that the FZA/PAA system can generate ·OH, 1O2, O2·ï¼, and Fe(Ⅳ), with ·OH playing a dominant role in ECs degradation. Additionally, the doped S facilitated electrochemical performance, Fe2+ regeneration and fixation in FZA. Practical application elucidated that the FZA/PAA system can work in complex environments to degrade various ECs without generating high-toxicity ingredients. Overall, valorizing SIA to FZA provides dual achievement in waste management and ECs removal.


Assuntos
Incineração , Esgotos , Sulfametoxazol , Zeolitas , Sulfametoxazol/química , Zeolitas/química , Esgotos/química , Catálise , Gerenciamento de Resíduos/métodos , Ferro/química
13.
Molecules ; 29(20)2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39459228

RESUMO

In the critical domain of wastewater treatment, the development of cost-effective, durable, and recyclable adsorbents with high adsorption capacities remains a significant challenge. This study introduces a novel magnetic bimetallic Metal-Organic Framework (MOF) adsorbent, MZIF-67-Co/Cu, doped with copper ions. The MZIF-67-Co/Cu adsorbent was successfully synthesized and structurally characterized, demonstrating remarkable selectivity for removing methyl orange (MO) from water. This high selectivity is attributed to the adsorbent's high porosity and Lewis base properties at the coordinating metal ion center. The incorporation of Cu ions significantly enhances the porous architecture and increases the number of metal adsorption sites, leading to an impressive maximum MO adsorption capacity of 39.02 mg/g under optimized conditions (0.5 g/L adsorbent concentration, pH 3.0, 250 rpm agitation speed, adsorption time > 10 min). The adsorption kinetics closely follow the pseudo-second-order model, and the isotherm data fit well with the Langmuir model. The primary adsorption mechanisms involve electrostatic attraction and mesoporous interaction. This study highlights MZIF-67-Co/Cu as a highly efficient adsorbent with magnetic recovery capabilities, positioning it as a promising candidate for addressing critical issues in wastewater treatment.

14.
Toxicol Mech Methods ; : 1-12, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39223849

RESUMO

Alveolar macrophages (AMs), the first line against the invasion of foreign invaders, play a predominant role in the pathogenesis of silicosis. Studies have shown that inhaled silica dust is recognized and engulfed by AMs, resulting in the production of large amounts of silica-induced reactive oxygen species (ROS), including particle-derived ROS and macrophage-derived ROS. These ROS change the microenvironment of the AMs where the macrophage phenotype is stimulated to swift from M0 to M1 and/or M2, and ultimately emerge as the M2 phenotype to trigger silicosis. This is a complex process accompanied by various molecular biological events. Unfortunately, the detailed processes and mechanisms have not been systematically described. In this review, we first systematically introduce the process of ROS induced by silica in AMs. Then, describe the role and molecular mechanism of M2-type macrophage polarization caused by silica-induced ROS. Finally, we review the mechanism of pulmonary fibrosis induced by M2 polarized AMs. We conclude that silica-induced ROS initiate the fibrotic process of silicosis by inducing macrophage into M2 phenotype, and that targeted intervention of silica-induced ROS in AMs can reprogram the macrophage polarization and ameliorate the pathogenesis of silicosis.

15.
BMC Bioinformatics ; 24(1): 193, 2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37170188

RESUMO

All the time, pancreatic cancer is a problem worldwide because of its high degree of malignancy and increased mortality. Neural network model analysis is an efficient and accurate machine learning method that can quickly and accurately predict disease feature genes. The aim of our research was to build a neural network model that would help screen out feature genes for pancreatic cancer diagnosis and prediction of prognosis. Our study confirmed that the neural network model is a reliable way to predict feature genes of pancreatic cancer, and immune cells infiltrating play an essential role in the development of pancreatic cancer, especially neutrophils. ANO1, AHNAK2, and ADAM9 were eventually identified as feature genes of pancreatic cancer, helping to diagnose and predict prognosis. Neural network model analysis provides us with a new idea for finding new intervention targets for pancreatic cancer.


Assuntos
Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Redes Neurais de Computação , Aprendizado de Máquina , Proteínas de Membrana/genética , Proteínas ADAM , Neoplasias Pancreáticas
16.
J Am Chem Soc ; 145(19): 10470-10474, 2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37146270

RESUMO

The formation of carbon-carbon bonds by pinacol coupling of aldehydes and ketones requires a large negative reduction potential, often realized with a stoichiometric reducing reagent. Here, we use solvated electrons generated via a plasma-liquid process. Parametric studies with methyl-4-formylbenzoate reveal that selectivity over the competing reduction to the alcohol requires careful control over mass transport. The generality is demonstrated with benzaldehydes, benzyl ketones, and furfural. A reaction-diffusion model explains the observed kinetics, and ab initio calculations provide insight into the mechanism. This study opens the possibility of a metal-free, electrically-powered, sustainable method for reductive organic reactions.

17.
Inorg Chem ; 62(38): 15465-15478, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37699414

RESUMO

Three new cyano-bridged FeII-MoIII complexes assembled from the [MoIII(CN)7]4- unit, FeII ions, and three pentadentate N3O2 ligands, namely {[Fe2H3(dapab)2][Mo(CN)6]}n·2H2O·3.5MeCN (1), [Fe(H2dapb)(H2O)][Fe(Hdapb)(H2O)][Mo(CN)6]·4H2O·3MeCN (2), and [Fe(H2dapba)(H2O)]2[Mo(CN)7]·6H2O (3) (H2dapab = 2,6-diacetylpyridine bis(2-aminobenzoylhydrazone), H2dapb = 2,6-diacetylpyridine bis(benzoylhydrazone), H2dapba = 2,6-diacetylpyridine bis(4-aminobenzoylhydrazone)), have been synthesized and characterized. Single-crystal structure analyses suggest that complex 1 contains a one-dimensional (1D) chain structure where two FeII ions are bridged by the in situ generated [MoIII(CN)6]3- unit through two trans-cyanide groups into trinuclear Fe2IIMoIII clusters that are further linked by the amino of the ligand into an infinite chain. Complexes 2 and 3 are cyano-bridged Fe2IIMoIII trinuclear clusters with two FeII ions connected by the [MoIII(CN)6]3- and [MoIII(CN)7]4- units, respectively. Direct current magnetic studies confirmed the ferromagnetic interactions between the cyano-bridged FeII and MoIII centers and significant easy-axis magnetic anisotropy for all three complexes. Furthermore, complexes 1-3 exhibit slow magnetic relaxation under a zero dc field, with relaxation barriers of 42.3, 21.6, and 14.4 K, respectively, making them the first examples of cyano-bridged FeII-MoIII single-molecule magnets.

18.
Environ Res ; 239(Pt 1): 117383, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37832763

RESUMO

Coastal nitrogen input has substantially increased due to human activity. However, much remains unknown about the nitrogen-driven patterns and the underlying genetic basis of coastal picoplankton. To investigate the response and mechanisms of picoplankton induced by nitrogen variation, we conducted in-situ investigations using high-throughput sequencing in the Bohai Sea and performed laboratory nitrogen simulation experiments accompanied by physiological, genomic, and transcriptomic analyses, with Synechococcus as a representative. The results of in-situ investigation revealed that Synechococcus clades I, III, WPC1, and VI of subcluster 5.1 (S5.1) are prevalent in strait areas characterized by robust water exchange with the North Yellow Sea, while clades II, VIII, and IX of S5.1, as well as subcluster 5.2 (S5.2) and subcluster 5.3 (S5.3) are more abundant in central and bay areas experiencing elevated nitrate and nitrite loads. The laboratory experiments further confirmed that inorganic nitrogen is a crucial determinant of diversity and niche partitioning of Synechococcus lineages. Besides, the raising inorganic nitrogen concentration within the current in-situ range (0.1-10 µmol L-1) enhances photosynthesis and carbon fixation of Synechococcus, however further escalation of inorganic nitrogen (100 µmol L-1) may hinder these processes instead. The phenomenon could be associated with the differential expression of genes in metabolic pathways regulating nitrogen metabolism, photosynthetic system II, and photosynthesis-antenna proteins in response to nitrogen concentration and type variation. These findings expand our understanding of the impact of macronutrient variation resulting from human activities on marine picoplankton and biogeochemical cycles.


Assuntos
Synechococcus , Humanos , Synechococcus/genética , Adaptação Fisiológica , Simulação por Computador , Perfilação da Expressão Gênica , Nitrogênio
19.
Ecotoxicol Environ Saf ; 252: 114593, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36724708

RESUMO

Zinc, an essential trace mineral, plays a pivotal role in cell proliferation, maintenance of redox homeostasis, apoptosis, and aging. Serum zinc concentrations are reduced in patients with polycystic ovary syndrome (PCOS). However, the underlying mechanism of the effects of zinc deficiency on the female reproductive system, especially oocyte quality, has not been fully elucidated. Thus, we established an in vitro experimental model by adding N,N,N',N'-Tetrakis(2-pyridylmethyl) ethylenediamine (TPEN) into the culture medium, and to determine the potential regulatory function of zinc during porcine oocytes maturation. In the present study, we found that zinc deficiency caused aberrant meiotic progress, accompanied by the disrupted cytoskeleton structure in porcine oocytes. Zinc deficiency impaired mitochondrial function and dynamics, leading to the increase of reactive oxygen species (ROS) and acetylation level of the antioxidative enzyme superoxide dismutase 2 (SOD2), eventually induced the occurrence of oxidative stress and early apoptosis. Moreover, zinc deficiency perturbed cytosolic Ca2+ homeostasis, lipid droplets formation, demonstrating the aberrant mitochondrial function in porcine oocytes. Importantly, we found that zinc deficiency in porcine oocytes induced the occurrence of mitophagy by activating the PTEN-induced kinase 1/Parkin signaling pathway. Collectively, our findings demonstrated that zinc was a critical trace mineral for maintaining oocyte quality by regulating mitochondrial function and autophagy in porcine oocytes.


Assuntos
Oligoelementos , Suínos , Feminino , Animais , Oligoelementos/metabolismo , Mitofagia , Oócitos/metabolismo , Zinco/toxicidade , Zinco/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Apoptose
20.
Chin J Physiol ; 66(6): 466-473, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38149559

RESUMO

Deep vein thrombosis (DVT) is a common complication in hematologic malignancies and immunologic disorders. Endothelial cell injury and dysfunction comprise the critical contributor for the development of DVT. A disintegrin and metalloproteinase with thrombospondin motifs 13 (ADAMTS13), a plasma metalloprotease that cleaves von Willebrand factor, acts as a critical regulator in normal hemostasis. This study was aimed to explore the role of ADAMTS13 in endothelial cell injury during DVT and the possible mechanism. First, human umbilical vein endothelial cells (HUVECs) were exposed to hydrogen peroxide (H2O2). Then, the mRNA and protein expressions of ADAMTS13 were evaluated with the reverse transcription-quantitative polymerase chain reaction and western blot. After treatment with recombinant ADAMTS13 (rADAMTS13; rA13), the viability and apoptosis of H2O2-induced HUVECs were assessed by cell counting kit-8 assay and terminal-deoxynucleoitidyl transferase-mediated nick end labeling staining. In addition, the levels of prostaglandin F1-alpha, endothelin-1, and reactive oxygen species were detected using the enzyme-linked immunosorbent assay and dichloro-dihydro-fluorescein diacetate assay. The expressions of proteins related to p38/extracellular signal-regulated kinase (ERK) signaling pathway were estimated with the western blot. Then, p79350 (p38 agonist) was used to pretreat cells to analyze the regulatory effects of rA13 on p38/ERK signaling in H2O2-induced HUVEC injury. The results revealed that ADAMTS13 expression was significantly downregulated in H2O2-induced HUVECs. The reduced viability and increased apoptosis of HUVECs induced by H2O2 were revived by ADAMTS13. ADAMTS13 also suppressed the oxidative stress in HUVECs after H2O2 treatment. Besides, ADAMTS13 was found to block p38/ERK signaling pathway, and p79350 reversed the impacts of ADAMTS13 on the damage of HUVECs induced by H2O2. To sum up, ADAMTS13 could alleviate H2O2-induced HUVEC injury through the inhibition of p38/ERK signaling pathway.


Assuntos
Proteína ADAMTS13 , Sistema de Sinalização das MAP Quinases , Trombose Venosa , Humanos , Peróxido de Hidrogênio/efeitos adversos , Trombose Venosa/metabolismo , Proteína ADAMTS13/metabolismo , Células Endoteliais da Veia Umbilical Humana , Estresse Oxidativo
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