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1.
Proc Natl Acad Sci U S A ; 121(4): e2305745121, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38236731

RESUMO

The development of vaccines, which induce effective immune responses while ensuring safety and affordability, remains a substantial challenge. In this study, we proposed a vaccine model of a restructured "head-to-tail" dimer to efficiently stimulate B cell response. We also demonstrate the feasibility of using this model to develop a paramyxovirus vaccine through a low-cost rice endosperm expression system. Crystal structure and small-angle X-ray scattering data showed that the restructured hemagglutinin-neuraminidase (HN) formed tetramers with fully exposed quadruple receptor binding domains and neutralizing epitopes. In comparison with the original HN antigen and three traditional commercial whole virus vaccines, the restructured HN facilitated critical epitope exposure and initiated a faster and more potent immune response. Two-dose immunization with 0.5 µg of the restructured antigen (equivalent to one-127th of a rice grain) and one-dose with 5 µg completely protected chickens against a lethal challenge of the virus. These results demonstrate that the restructured HN from transgenic rice seeds is safe, effective, low-dose useful, and inexpensive. We provide a plant platform and a simple restructured model for highly effective vaccine development.


Assuntos
Oryza , Paramyxovirinae , Vacinas Virais , Animais , Galinhas , Vírus da Doença de Newcastle , Oryza/genética , Desenho Universal , Epitopos , Anticorpos Antivirais
2.
J Biol Chem ; 300(1): 105573, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38122901

RESUMO

Lytic polysaccharide monooxygenases (LPMOs) oxidatively depolymerize recalcitrant polysaccharides, which is important for biomass conversion. The catalytic domains of many LPMOs are linked to carbohydrate-binding modules (CBMs) through flexible linkers, but the function of these CBMs in LPMO catalysis is not well understood. In this study, we utilized MtLPMO9L and MtLPMO9G derived from Myceliophthora thermophila to investigate the impact of CBMs on LPMO activity, with particular emphasis on their influence on H2O2 tolerance. Using truncated forms of MtLPMO9G generated by removing the CBM, we found reduced substrate binding affinity and enzymatic activity. Conversely, when the CBM was fused to the C terminus of the single-domain MtLPMO9L to create MtLPMO9L-CBM, we observed a substantial improvement in substrate binding affinity, enzymatic activity, and notably, H2O2 tolerance. Furthermore, molecular dynamics simulations confirmed that the CBM fusion enhances the proximity of the active site to the substrate, thereby promoting multilocal cleavage and impacting the exposure of the copper active site to H2O2. Importantly, the fusion of CBM resulted in more efficient consumption of H2O2 by LPMO, leading to improved enzymatic activity and reduced auto-oxidative damage of the copper active center.


Assuntos
Domínio Catalítico , Peróxido de Hidrogênio , Oxigenases de Função Mista , Polissacarídeos , Sordariales , Cobre/metabolismo , Peróxido de Hidrogênio/efeitos adversos , Peróxido de Hidrogênio/metabolismo , Oxigenases de Função Mista/metabolismo , Polissacarídeos/metabolismo , Sordariales/enzimologia , Sordariales/metabolismo , Simulação de Dinâmica Molecular
3.
Plant J ; 114(3): 613-635, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36799458

RESUMO

As an essential enzyme in the uridine diphosphate (UDP)-GlcNAc biosynthesis pathway, the significant role of N-acetylglucosamine phosphate mutase (AGM) remains unknown in plants. In the present study, a functional plant AGM (AtAGM) was identified from Arabidopsis thaliana. AtAGM catalyzes the isomerization of GlcNAc-1-P and GlcNAc-6-P, and has broad catalytic activity on different phosphohexoses. UDP-GlcNAc contents were significantly decreased in AtAGM T-DNA insertional mutants, which caused temperature-dependent growth defects in seedlings and vigorous growth in adult plants. Further analysis revealed that protein O-GlcNAcylation but not N-glycosylation was dramatically impaired in Atagm mutants due to UDP-GlcNAc shortage. Combined with the results from O-GlcNAcylation or N-glycosylation deficient mutants, and O-GlcNAcase inhibitor all suggested that protein O-GlcNAcylation impairment mainly leads to the phenotypic variations of Atagm plants. In conclusion, based on the essential role in UDP-GlcNAc biosynthesis, AtAGM is important for plant growth mainly via protein O-GlcNAcylation-level regulation.


Assuntos
Arabidopsis , Arabidopsis/metabolismo , Acetilglucosamina/metabolismo , Proteínas/metabolismo , Glicosilação , Fosfatos/metabolismo , Processamento de Proteína Pós-Traducional
4.
J Cell Biochem ; 125(1): 100-114, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38031891

RESUMO

Osteoporosis (OP) is a bone remodeling disease characterized by an imbalance between bone resorption and formation. Osteoclasts are the primary therapeutic targets for treating bone destruction. Koumine (KM), the most bioactive component in Gelsemium alkaloids, exhibits antitumor, immunosuppressive, anti-inflammatory, and analgesic properties. However, the effects of bone loss have not been well studied. This study conducted in vitro and in vivo verification experiments on KM. The results showed that KM inhibited bone resorption and tartrate-resistant acid phosphatase positive (TRAP+) osteoclasts development by mature osteoclasts in a dose-dependent manner. Moreover, KM prevented OVX-induced OP in vivo and potentially inhibited ubiquitination, a process closely related to various biological activities, including protein interaction, transcription, and transmembrane signal transduction regulation, especially within the nuclear factor-κB (NF-κB) pathway. Previous studies have demonstrated that several proteins ubiquitination promotes osteoclastogenesis, our study indicated that KM inhibits early NF-κB activation and receptor activator of NF-κB ligand induced ubiquitination, a critical factor in osteoclast differentiation. In conclusion, our research suggests that KM holds potential as an effective therapeutic agent for OP.


Assuntos
Reabsorção Óssea , Alcaloides Indólicos , Osteoporose , Feminino , Humanos , NF-kappa B/metabolismo , Osteoclastos/metabolismo , Osteogênese , Reabsorção Óssea/tratamento farmacológico , Reabsorção Óssea/prevenção & controle , Reabsorção Óssea/metabolismo , Osteoporose/tratamento farmacológico , Osteoporose/etiologia , Osteoporose/prevenção & controle , Ovariectomia/efeitos adversos , Ligante RANK/metabolismo , Diferenciação Celular
5.
Exp Dermatol ; 33(4): e15082, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38664884

RESUMO

As a chronic relapsing disease, psoriasis is characterized by widespread skin lesions. The Psoriasis Area and Severity Index (PASI) is the most frequently utilized tool for evaluating the severity of psoriasis in clinical practice. Nevertheless, long-term monitoring and precise evaluation pose difficulties for dermatologists and patients, which is time-consuming, subjective and prone to evaluation bias. To develop a deep learning system with high accuracy and speed to assist PASI evaluation, we collected 2657 high-quality images from 1486 psoriasis patients, and images were segmented and annotated. Then, we utilized the YOLO-v4 algorithm to establish the model via four modules, we also conducted a human-computer comparison through quadratic weighted Kappa (QWK) coefficients and intra-class correlation coefficients (ICC). The YOLO-v4 algorithm was selected for model training and optimization compared with the YOLOv3, RetinaNet, EfficientDet and Faster_rcnn. The model evaluation results of mean average precision (mAP) for various lesion features were as follows: erythema, mAP = 0.903; scale, mAP = 0.908; and induration, mAP = 0.882. In addition, the results of human-computer comparison also showed a median consistency for the skin lesion severity and an excellent consistency for the area and PASI score. Finally, an intelligent PASI app was established for remote disease assessment and course management, with a pleasurable agreement with dermatologists. Taken together, we proposed an intelligent PASI app based on the image YOLO-v4 algorithm that can assist dermatologists in long-term and objective PASI scoring, shedding light on similar clinical assessments that can be assisted by computers in a time-saving and objective manner.


Assuntos
Algoritmos , Aprendizado Profundo , Psoríase , Índice de Gravidade de Doença , Psoríase/patologia , Humanos , Processamento de Imagem Assistida por Computador/métodos
6.
Brain Behav Immun ; 121: 13-25, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39025414

RESUMO

Alterations in steroid hormone regulation have been implicated in the etiology and progression of autism spectrum disorders (ASD), with the enzyme cytochrome P450 family 11 subfamily A member 1 (CYP11A1)-a key catalyst in cholesterol side-chain cleavage, prominently expressed in the adrenal glands, ovaries, testes, and placenta-standing at the forefront of these investigations. The potential link between aberrations in placental Cyp11a1 expression and the resultant neurodevelopmental disorders, along with the mechanisms underpinning such associations, remains inadequately delineated. In this study, we employed a placental trophoblast-specific Cyp11a1 Hipp11 (H11) knock-in murine model to dissect the phenotypic manifestations within the placenta and progeny, thereby elucidating the underlying mechanistic pathways. Behavioral analyses revealed a diminution in social interaction capabilities alongside an augmented anxiety phenotype, as evidenced by open field and elevated plus maze assessments; both phenotypes were ameliorated after vitamin D3 supplementation. Electrophysiological assays underscored the augmented inhibition of paired-pulse facilitation, indicating impaired neuroplasticity in Cyp11a1 H11-modified mice. An elevation in progesterone concentrations was noted, alongside a significant upregulation of Th1-related cytokines (IL-6 and TNFα) across the plasma, placental, and frontal cortex-a pathological state mitigable through vitamin D3 intervention. Western blotting revealed a vitamin D-mediated rectification of vitamin D receptor and PGC-1α expression dysregulations. Immunofluorescence assays revealed microglial activation in the knock-in model, which was reversible upon vitamin D3 treatment. In conclusion, Cyp11a1 overexpression in the placenta recapitulated an autism-like phenotype in murine models, and vitamin D3 administration effectively ameliorated the resultant neurobehavioral and neuroinflammatory derangements. This study substantiates the application of Cyp11a1 as a biomarker in prenatal diagnostics and posits that prenatal vitamin D3 supplementation is a viable prophylactic measure against perturbations in steroid hormone metabolism associated with ASD pathogenesis.

7.
J Endovasc Ther ; : 15266028241253128, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38733303

RESUMO

OBJECTIVE: The objective was to present our experience on managing mycotic infrarenal abdominal aortic aneurysm (MIAAA) through a retrospective cohort study. METHODS: Data of patients with MIAAA managed in our center from July 2016 to October 2022 were retrospectively analyzed. The diagnosis of MIAAA was made based on: (1) preoperative clinical signs of infection; (2) elevated serologic infection parameters; (3) para-aneurysmal infection features on enhanced computed tomography; and (4) positive blood or tissue cultures. All the patients received standard antibiotic therapy. Surgical management including endovascular aneurysm repair (EVAR), initial EVAR followed by open re-operation, and initial open surgical repair (OSR) were conducted according to disease seriosity, physical condition, and patient's will. Infection index and clinical outcome were evaluated during the follow-up time. RESULTS: A total of 23 patients (21 men; averaged=66.3 years, range=49-79 years) were included, with a mean follow-up time of 19.9 months (range=1-75 months). Bacteria culture from blood or tissue specimen was positive in 15 patients (Salmonella, n=8; Escherichia coli, n=3; methicillin-sensitive Staphylococcus aureus [MSSA], n=1; Klebsiella pneumoniae, n=1; Staphylococcus epidermidis, n=1; Mycobacterium tuberculosis, n=1). Seven patients received OSR as the initial surgical intervention, whereas 14 patients chose EVAR instead. The 2 conservatively managed patients (refused surgery) died within 30 days. The 7 patients who received initial OSR survived till now. Among the 14 patients who underwent initial EVAR, infection deteriorated without exception (14/14, 100%). Three of these patients refused re-operation and died within 6 months. Eleven patients received secondary surgical intervention (10 cases of aneurysm and endograft resection, thorough debridement, subclavian to bi-femoral artery bypass, or in situ aorta reconstruction; 1 case of laparoscopic debridement) and 7 survived the follow-up time. The overall mortality rate was 39.1% (9/23). The mortality rates differed greatly following different intervention methods (merely antibiotic management, 100%; initial open operation, 0%; initial EVAR without secondary operation, 100%; initial EVAR plus secondary operation, 36.4%). CONCLUSIONS: Open surgical repair is still the first choice for hemodynamically stable and low-risk patients. Merely EVAR is related with disastrous results, which should be reserved as a temporary alternative for patients with ruptured aneurysms, hemodynamic instability or high surgical risk, and followed by timely secondary OSR. CLINICAL IMPACT: The management of mycotic or primary-infected aortic aneurysm is challenging; treatment remains controversial. Our center has reviewed our experience over the past 6 years and found that open surgical repair is still the first choice for hemodynamically stable and low-risk patients. Merely endovascular aneurysm repair (EVAR) is related with disastrous results, which should be reserved as a temporary alternative for patients with ruptured aneurysms, hemodynamic instability or high surgical risk, and followed by timely secondary open surgical repair.

8.
Mol Biol Rep ; 51(1): 525, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632128

RESUMO

BACKGROUND: A series of previous investigations have revealed that p-Smad3 plays a facilitative role in the differentiation and maturation of osteoblasts, while also regulating the expression of certain intercellular communication factors. However, the effects of p-Smad3 in osteoblasts before and after maturation on the proliferation, migration, differentiation, apoptosis and other cellular behaviors of osteoclasts have not been reported. METHODS: MC3T3-E1 cells were cultured in osteogenic induction medium for varying durations, After that, the corresponding conditioned medium was collected and the osteoclast lineage cells were treated. To elucidate the regulatory role of p-Smad3 within osteoblasts, we applied the activator TGF-ß1 and inhibitor SIS3 to immature and mature osteoblasts and collected corresponding conditioned media for osteoclast intervention. RESULTS: We observed an elevation of p-Smad3 and Smad3 during the early stage of osteoblast differentiation, followed by a decline in the later stage. we discovered that as osteoblasts mature, their conditioned media inhibit osteoclasts differentiation and the osteoclast-coupled osteogenic effect. However, it promotes apoptosis in osteoclasts and the angiogenesis coupled with osteoclasts. p-Smad3 in immature osteoblasts, through paracrine effects, promotes the migration, differentiation, and osteoclast-coupled osteogenic effects of osteoclast lineage cells. For mature osteoblasts, p-Smad3 facilitates osteoclast apoptosis and the angiogenesis coupled with osteoclasts. CONCLUSIONS: As pre-osteoblasts undergo maturation, p-Smad3 mediated a paracrine effect that transitions osteoclast cellular behaviors from inducing differentiation and stimulating bone formation to promoting apoptosis and coupling angiogenesis.


Assuntos
Osteoclastos , Osteogênese , Proteína Smad3 , Diferenciação Celular , Meios de Cultivo Condicionados/farmacologia , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Osteogênese/genética , Osteogênese/fisiologia , Animais , Camundongos , Proteína Smad3/genética , Proteína Smad3/metabolismo
9.
Cell Mol Biol (Noisy-le-grand) ; 70(3): 95-101, 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38650149

RESUMO

Osteoporosis is a common chronic bone disorder in postmenopausal women. Ginsenosides are primary active components in ginseng and the effects of various ginsenoside variants in osteoporosis treatment have been widely revealed. We planned to explore the impact of ginsenoside Rc on bone resorption in an osteoporosis rat model. We used ovariectomized rats to assess the potential impact of ginsenoside Rc on osteoporosis. µ-CT was implemented for analyzing the microstructure of the distal left femur in rats. H&E staining together with Masson staining were applied for bone histomorphometry evaluation. ELISA kits were implemented to detect serum concentrations of TRACP-5b, OCN, CTX, as well as PINP. Ginsenoside Rc treatment lessened the serum levels of TRACP-5b as well as CTX, while increasing serum levels of OCN, and PINP of OVX rats. Moreover, we found that ginsenoside Rc contributed to the synthesis of type I collagen via increasing Col1a1 and Col1a2 levels in femur tissues of ovariectomized rats. Our findings also revealed that ginsenoside Rc activated the TGF-ß/Smad pathway by increasing TGF-ß as well as phosphorylated Smad2/3 protein levels. Ginsenoside Rc alleviates osteoporosis in rats through promoting the TGF-ß/Smad pathway.


Assuntos
Ginsenosídeos , Osteoporose , Ovariectomia , Ratos Sprague-Dawley , Transdução de Sinais , Fator de Crescimento Transformador beta , Ginsenosídeos/farmacologia , Ginsenosídeos/uso terapêutico , Animais , Feminino , Osteoporose/tratamento farmacológico , Osteoporose/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Crescimento Transformador beta/metabolismo , Fêmur/efeitos dos fármacos , Fêmur/metabolismo , Fêmur/patologia , Proteínas Smad/metabolismo , Ratos , Colágeno Tipo I/metabolismo , Microtomografia por Raio-X , Fosfatase Ácida Resistente a Tartarato/metabolismo , Osteocalcina/metabolismo , Osteocalcina/sangue , Modelos Animais de Doenças , Pró-Colágeno/metabolismo , Pró-Colágeno/sangue
10.
Biomed Eng Online ; 23(1): 5, 2024 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-38221632

RESUMO

BACKGROUND: Breast fibroadenoma poses a significant health concern, particularly for young women. Computer-aided diagnosis has emerged as an effective and efficient method for the early and accurate detection of various solid tumors. Automatic segmentation of the breast fibroadenoma is important and potentially reduces unnecessary biopsies, but challenging due to the low image quality and presence of various artifacts in sonography. METHODS: Human learning involves modularizing complete information and then integrating it through dense contextual connections in an intuitive and efficient way. Here, a human learning paradigm was introduced to guide the neural network by using two consecutive phases: the feature fragmentation stage and the information aggregation stage. To optimize this paradigm, three fragmentation attention mechanisms and information aggregation mechanisms were adapted according to the characteristics of sonography. The evaluation was conducted using a local dataset comprising 600 breast ultrasound images from 30 patients at Suining Central Hospital in China. Additionally, a public dataset consisting of 246 breast ultrasound images from Dataset_BUSI and DatasetB was used to further validate the robustness of the proposed network. Segmentation performance and inference speed were assessed by Dice similarity coefficient (DSC), Hausdorff distance (HD), and training time and then compared with those of the baseline model (TransUNet) and other state-of-the-art methods. RESULTS: Most models guided by the human learning paradigm demonstrated improved segmentation on the local dataset with the best one (incorporating C3ECA and LogSparse Attention modules) outperforming the baseline model by 0.76% in DSC and 3.14 mm in HD and reducing the training time by 31.25%. Its robustness and efficiency on the public dataset are also confirmed, surpassing TransUNet by 0.42% in DSC and 5.13 mm in HD. CONCLUSIONS: Our proposed human learning paradigm has demonstrated the superiority and efficiency of ultrasound breast fibroadenoma segmentation across both public and local datasets. This intuitive and efficient learning paradigm as the core of neural networks holds immense potential in medical image processing.


Assuntos
Neoplasias da Mama , Fibroadenoma , Humanos , Feminino , Fibroadenoma/diagnóstico por imagem , Aprendizagem , Ultrassonografia , Ultrassonografia Mamária , Neoplasias da Mama/diagnóstico por imagem , Redes Neurais de Computação , Processamento de Imagem Assistida por Computador
11.
Ecotoxicol Environ Saf ; 273: 116150, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38430579

RESUMO

Nickel (Ni), an environmental health hazard, is nephrotoxic to humans, but the exact mechanism is unknown. This study aims to identify whether nephrotoxicity is associated with autophagy. Here, nickel chloride (NiCl2) increased autophagy in TCMK-1 cells. NiCl2 induces autophagy through Akt and AMPK/mTOR pathways. Next, oxidative stress was investigated in NiCl2-induced autophagy. The findings demonstrated that the antioxidant (NAC) or mitochondrial targeted antioxidant (Mito-TEMPO) attenuated NiCl2-induced autophagy, reversed the influence on AMPK-mTOR and Akt pathways. Additionally, our study examined the role of autophagy in NiCl2-induced nephrotoxicity. Autophagy inhibition with 3-MA could inhibit cell viability and increase apoptosis in the TCMK-1 cells, however, autophagy promotion with rapamycin relieved cytotoxicity and decreased apoptosis. Additionally, co-treatment with Z-VAD-FMK reduced cytotoxicity, but did not affect autophagy. Besides, NiCl2 can increase the level of mitophagy in vivo and vitro. Mitophagy inhibition could inhibit cell viability and increase apoptosis in the TCMK-1 cells, whereas, promotion of mitophagy could increase cell viability and decrease apoptosis. In summary, above-mentioned results showed that NiCl2 induces autophagy in TCMK-1 cells through oxidative stress-dependent AMPK/AKT-mTOR pathway, autophagy plays a role in reducing NiCl2-induced renal toxicity, and a major mechanism in autophagy's inhibitory effect on NiCl2-induced apoptosis may be mitophagy.


Assuntos
Antioxidantes , Proteínas Proto-Oncogênicas c-akt , Humanos , Antioxidantes/farmacologia , Níquel/toxicidade , Proteínas Quinases Ativadas por AMP/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Apoptose , Autofagia
12.
Environ Toxicol ; 39(6): 3597-3611, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38488660

RESUMO

Nickel (Ni) is recognized as a carcinogenic metal, and its widespread use has led to severe environmental and health problems. Although the lung is among the main organs affected by Ni, the precise mechanisms behind this effect remain poorly understood. This study aimed to elucidate the physiological mechanisms underlying Ni-induced pulmonary fibrosis (PF), using various techniques including histopathological detection, biochemical analysis, immunohistochemistry, western blotting, and quantitative real-time PCR. Mice were treated with nickel chloride (NiCl2), which induced PF (detected by Masson staining), up-regulation of α-smooth muscle actin (α-SMA), and collagen-1 mRNA and protein expression. NiCl2 was found to induce PF by: activation of the epithelial-mesenchymal transition (EMT) and the transforming growth factor-ß1 (TGF-ß1)/Smad signaling pathway; up-regulation of protein and mRNA expression of TGF-ß1, p-Smad2, p-Smad3, vimentin, and N-cadherin; and down-regulation of protein and mRNA expression of E-cadherin. In addition, NiCl2 treatment increased malondialdehyde content while inhibiting antioxidant activity, as indicated by decreased catalase, total antioxidant capacity, and superoxide dismutase activities, and glutathione content. Co-treatment with the effective antioxidant and free radical scavenger N-acetyl cysteine (NAC) plus NiCl2 was used to study the effects of oxidative stress in NiCl2-induced PF. The addition of NAC significantly mitigated NiCl2-induced PF, and reversed activation of the TGF-ß1/Smad signaling pathway and EMT. NiCl2-induced PF was therefore shown to be due to EMT activation via the TGF-ß1/Smad signaling pathway, mediated by oxidative stress.


Assuntos
Transição Epitelial-Mesenquimal , Níquel , Estresse Oxidativo , Fibrose Pulmonar , Transdução de Sinais , Animais , Masculino , Camundongos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Pulmão/patologia , Pulmão/metabolismo , Níquel/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/patologia , Transdução de Sinais/efeitos dos fármacos , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta1/metabolismo
13.
J Am Chem Soc ; 145(6): 3470-3477, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36724407

RESUMO

The multi-redox mechanism involving multi-sites has great implications to dictate the catalytic water oxidation. Understanding the sequential dynamics of multi-steps in oxygen evolution reaction (OER) cycles on working catalysts is a highly important but challenging issue. Here, using quasi-operando transient absorption (TA) spectroscopy and a typical photosensitization strategy, we succeeded in resolving the sequential oxidation kinetics involving multi-active sites for water oxidation in OER catalytic cycle, with Co3O4 nanoparticles as model catalysts. When OER initiates from fast oxidation of surface Co2+ ions, both surface Co2+ and Co3+ ions are active sites of the multi-cobalt centers for water oxidation. In the sequential kinetics (Co2+ → Co3+ → Co4+), the key characteristic is fast oxidation and slow consumption for all the cobalt species. Due to this characteristic, the Co4+ intermediate distribution plays a determining role in OER activity and results in the slow overall OER kinetics. These insights shed light on the kinetic understanding of water oxidation on heterogeneous catalysts with multi-sites.

14.
Anal Chem ; 95(13): 5489-5493, 2023 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-36962078

RESUMO

Notum, one of the key serine hydrolases in mammals, hydrolyzes the palmitoleoyl moieties of many important proteins and modulates multiple signaling pathways including Wnt/ß-catenin signaling. Notum is tightly associated with multiple human diseases, but the reliable and practical tools for sensing Notum activities in complex biological systems are rarely reported. Herein, an efficient strategy was used to rationally construct a specific bioluminescent substrate for Notum. Following computer-aided molecular design and experimental verification, octanoyl luciferin (OL) was selected as the optimum substrate for human Notum, with excellent specificity, high detection sensitivity and high signal-to-noise ratio. Under physiological conditions, OL was readily hydrolyzed by Notum or Notum-containing biological specimens to release d-luciferin that could be easily detected by various fluorescence devices in the presence of luciferase. The applicability of OL for real-time sensing native Notum was examined in living cells, extracellular matrix, and tissue preparations. OL was also used for constructing a high-throughput assay for screening of Notum inhibitors, while a natural compound (bergapten) was newly identified as a potent Notum inhibitor. Collectively, this study devises a reliable and easy-to-use tool for sensing Notum activities in biological systems, which will strongly facilitate hNotum-associated fundamental studies, disease diagnosis, and drug discovery.


Assuntos
Hidrolases , Neoplasias , Animais , Humanos , Hidrolases/metabolismo , Via de Sinalização Wnt , Mamíferos/metabolismo , Esterases/metabolismo
15.
Fish Shellfish Immunol ; 136: 108719, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37003497

RESUMO

The large yellow croaker (Larimichthys crocea) is the most productive mariculture fish in China, and its aquaculture scale is expanding along the southeastern coast of China, but that development is causing environmental damage by increasing the use of antibiotics and other chemicals. How to improve fish immunity through non-antibiotic substances is still a problem facing aquaculture industry. At present, the experiments have shown that Isaria cicadae spent substrate (IC) can improve the growth performance and immunity of Oreochromis niloticus. Therefore, I. cicadae may be a natural alternative to antibiotic for aquaculture. In order to study the effects of IC on growth performance, serum biochemical indices, intestinal microbiota, and intestinal metabolism of large yellow croakers, the fish were divided into three groups with three replicates in each group. Basal diet, basal diet with 2% and 6% IC supplementation (IC2 and IC6 groups), respectively. The results showed that weight gain rate (WG) and specific growth rate (SGR) of large yellow croaker significantly increased (P < 0.05) in IC6 group. The content of triglyceride (TG), low density lipoprotein cholesterol (LDL-C), total protein (TP) and albumin (ALB) increased significantly (P < 0.05), and total cholesterol (T-CHO) decreased significantly (P < 0.05) in IC2 group. Compared to IC0 group, the activity of malondialdehyde (MDA) , superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) increased significantly (P < 0.05) in IC2 group, the activity of total antioxidant capacity (T-AOC) and GSH-Px increased significantly (P < 0.05) in IC6 group, and the activity of lysozyme (LZM) increased significantly in IC2 and IC6 groups. The addition of IC in the diets significantly increased the diversity of the microbial community in the intestine of large yellow croaker (P < 0.05), significantly improved the relative abundance of Acidobacteriota (P < 0.05) at the phylum level, and reduced the relative abundance of Bacteroidota, Desulfobacterota, and Synergistota (P < 0.05). At the genus level, the relative abundance of Bacteroides, Cetobacterium and Mycoplasma, which are dominant bacteria in fish gut, significantly increased (P < 0.05). The relative abundance of Ruminofilibacter, Desulfomicrobium, DMER64, Syntrophomonas, Hydrogenophaga, and Aminobacterium reduced significantly (P < 0.05). Among them, Ruminofilibacter, DMER64, Syntrophomonas and Hydrogenophaga are bacteria that can participate in the hydrolysis and acidification of organic matter, while DMER64 is the hydrogen carrier. The intestinal metabolome analysis showed that IC could improve metabolic composition and function, which was related to host immunity and metabolism. In conclusion, I. cicadae can improve the growth performance, regulate the lipid metabolism and immune and antioxidant capacity of large yellow croakers by regulating intestinal microbiota and intestinal metabolism. This study provides a reference for the application of IC in aquaculture.


Assuntos
Ciclídeos , Microbioma Gastrointestinal , Animais , Antioxidantes/metabolismo , Dieta/veterinária , Ciclídeos/metabolismo , Metaboloma
16.
Int J Hyperthermia ; 40(1): 2202372, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37094818

RESUMO

OBJECTIVE: To investigate the histopathological findings and follow-up outcome of focused ultrasound ablation surgery (FUAS) treatment of multiple fibroadenomas (FA). METHODS: A total of 20 patients with 101 multiple FAs were enrolled. After one session FUAS ablation, 21 lesions (≥15.0 mm) were surgically removed within one week for histopathological analysis, including 2, 3, 5-triphenyltetrazolium chloride (TTC) staining, H&E staining, nicotinamide adenine dinucleotide (NADH) -flavretin enzyme staining, Transmission electron microscope (TEM) and scanning electron microscope (SEM). The remaining 80 lesions were followed up at 3, 6 and 12 months after treatment. RESULTS: All ablation procedures were performed successfully. Pathologic findings showed that irreversible damage of FA was confirmed. TTC, H&E and NADH staining and TEM/SEM demonstrated tumor cell death and tumor structural destruction at the gross, cellular, and subcellular levels, respectively. The median shrinkage rate at 12 months post-FUAS was 66.4 (43.6, 89.5) %. CONCLUSION: Histopathological analysis for FAs after FUAS treatment proved that FUAS could effectively induce irreversible coagulative necrosis of FA, and the tumor volume would gradually shrink in follow-up. FUAS was safe and effective to treat multiple FAs with good cosmesis.Key pointsThis study was the first study of detailed histopathological analysis for FAs after FUAS treatment.FUAS can effectively induce irreversible coagulative necrosis of fibroadenoma cells.FUAS ablation of multiple fibroadenomas is safe and effective.


Assuntos
Neoplasias da Mama , Fibroadenoma , Humanos , Feminino , Fibroadenoma/patologia , Seguimentos , NAD , Neoplasias da Mama/patologia , Necrose
17.
BMC Psychiatry ; 23(1): 105, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36788524

RESUMO

BACKGROUND: Autism spectrum disorders (ASD) is a neurodevelopmental disorder with high incidence rate and difficult diagnosis. The purpose of this study was to explore whether salivary cortisol, dehydroepiandrosterone (DHEA) and pregnenolone can be used as biomarkers of ASD children. METHODS: The saliva samples of 55 boys with ASD were collected as the experimental group, and the saliva samples of 24 neurotypical boys were collected as the control group. The Child Behavior Checklist (CBCL), Autism Behavior Checklist (ABC), Social Responsiveness Scale (SRS), Repetitive Behavior Scale (RBS) were used to assess the severity of symptoms in boys with ASD. Cortisol, DHEA and pregnenolone concentrations in saliva were measured using an ABSSCIEX QTRAP® 6500 + LC/MS/MS system. SPSS 23.0 was used for statistical analysis. Comparisons between the two groups which conform to normal distribution were performed by T-test, and those which don't conform to normal distribution were performed by Mann-Whitney U test. Correlation analysis between two variables was performed using Spearman's correlation analysis. Receiver operating characteristic curve (ROC) analysis was performed to evaluate the discriminatory sensitivity of each hormone between ASD and normal control groups. Logistic regression models were used to analyze whether DHEA and salivary pregnenolone can be used as a biomarker of ASD. RESULTS: There were no significant differences in age, and weight between the ASD group and the normal control group. The ABC, SRS, RBS and CBCL scale scores in the ASD group were significantly higher than those in the normal control group. The salivary DHEA and pregnenolone concentrations in the ASD group were significantly higher than those in the normal control group, but there was no significant difference in cortisol. Spearman's correlation analysis showed that only pregnenolone associated with ABC. Logistic regression model analysis suggested that pregnenolone in saliva was an independent predictor of ASD. ROC analysis found that pregnenolone had good discrimination sensitivity between ASD and normal controls. CONCLUSION: Gave salivary preoperative a space for utilization as biomarker as number of cases are limited to this high expectation.


Assuntos
Transtorno do Espectro Autista , Masculino , Criança , Humanos , Transtorno do Espectro Autista/diagnóstico , Hidrocortisona , Espectrometria de Massas em Tandem , Biomarcadores , Desidroepiandrosterona
18.
Artigo em Inglês | MEDLINE | ID: mdl-36209958

RESUMO

Aquaculture has greater potential for seafood production than wild capture fisheries. To meet the growing demand for seafood, China's marine aquaculture industry has begun building deep-water cages in the open sea. However, under these conditions, fish encounter strong currents and waves, and ensuring their healthy growth is key to the farming process. To address these issues, it is necessary to study the sustained swimming abilities of cultured fish species. Blackhead seabream (Acanthopagrus schlegelii) and red drum (Sciaenops ocellatus) are traditional economic fish species in China; however, their sustained swimming ability under a constant current has been underexplored. Therefore, we examined the endurance swimming ability of three size classes of blackhead seabream and red drum at 20 °C. The fish were then subjected to swimming tests of 0, 30, 60, 90, 120, and 150 min at a constant swimming speed of 0.55 m/s (0.80 m/s), 0.65 m/s (0.90 m/s), and 0.70 m/s (0.98 m/s). The fish were then dissected to obtain muscle, blood, and liver samples; sample metabolite concentrations were measured at six time points, each of which guaranteed five sets of valid data. The results indicated that red drum has a significantly stronger swimming ability, and can be cultured in waters with a short-term flow rate not exceeding 0.75 m/s or 3.5 BL/s. Further, blackhead seabream can be cultured in waters with a flow velocity lower than 0.55 m/s or 2.5 BL/s. The species-related metabolic differences were mainly reflected in the hepatic glycogen and blood glucose concentrations, and those in swimming ability caused by body length were mainly reflected by the hepatic glycogen concentration. The hepatic glycogen concentration had the most significant effect on fish with body lengths >28 cm (P < 0.05). Overall, the experimental results indicated that the liver plays a major role in the physiological level of fish swimming fatigue, providing a direction for further research.


Assuntos
Perciformes , Dourada , Animais , Natação/fisiologia , Glicogênio Hepático , Fadiga
19.
Altern Ther Health Med ; 29(6): 400-407, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37384403

RESUMO

Background: Osteoporosis is a systemic bone disease characterized by decreased bone density and quality, destruction of bone microstructure, and increased bone fragility. Extracellular vesicles are lipid bilayer nanoparticles that participate in intercellular communication. Extracellular vesicles are becoming popular in the study of osteoporosis and the bone cell microenvironment. Extracellular vesicles can transmit cell signals and regulate bone homeostasis. Our previous studies revealed that the Chinese herbal medicine Guilu Erxian Glue promotes type I collagen synthesis and osteoprotegerin secretion by osteoblasts in rats, reverses the imbalance of bone homeostasis, and alleviates osteoporosis. Objective: We investigated how osteoblast-derived extracellular vesicles treated with Guilu Erxian Glue affected osteoclasts in vitro. Methods: We quantified osteoclast differentiation of RAW 264.7 using TRAP staining, cell apoptosis using flow cytometry, extracellular vesicle uptake by fluorescence tracing, bone absorption functions by bone resorption lacuna , and transcription of key genes by quantitative real-time PCR. Results: Fluorescently labeled mouse preosteoblastic MC3T3-E1 cells secreted nanoscale substances less than 1 µm in diameter. Mouse macrophage RAW 264.7 cells adsorbed these nanoparticles and PKH26-labeled extracellular vesicles derived from MC3T3-E1 cells on the cell membrane surface. Extracellular vesicles from MC3T3-E1 cells treated with Guilu Erxian Glue inhibited the differentiation of osteoclasts induced by receptor activator of nuclear factor-κB ligand and macrophage colony-stimulating factor and reduced the number of lacunae formed by osteoclasts in vitro compared with controls. Extracellular vesicles from MC3T3-E1 cells treated with Guilu Erxian Glue downregulated the relative messenger RNA expression of c-Fos, cathepsin K, nuclear factor of activated T cells 1, and tartrate-resistant acid phosphatase in osteoclasts, which may be part of the mechanism by which they regulate osteoclasts. Conclusions: Our results demonstrate that extracellular vesicles are essential for signal exchange between osteoblasts and osteoclasts. Although we do not know how Guilu Erxian Glue affects the signaling molecules carried by extracellular vesicles, we have shown for the first time, to our knowledge, that Guilu Erxian Glue can inhibit osteoclast differentiation and function via osteoblast-derived extracellular vesicles. Our findings are conducive to providing a new target for the development of osteoporosis drugs.


Assuntos
Reabsorção Óssea , Medicamentos de Ervas Chinesas , Osteoporose , Ratos , Camundongos , Animais , Osteoclastos/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Osteoblastos/metabolismo , Reabsorção Óssea/tratamento farmacológico , Reabsorção Óssea/metabolismo , Osteoporose/tratamento farmacológico
20.
Ecotoxicol Environ Saf ; 259: 115049, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37235900

RESUMO

Nickel, as a widely polluted metal, has been shown nephrotoxicity. Ferroptosis is a new type of cell death driven by iron-dependent lipid peroxidation. Our study found that nickel chloride (NiCl2) induced ferroptosis in mouse kidney and TCMK-1 cells. The iron content was significantly increased in the kidney and TCMK-1 cells after NiCl2 treatment. Lipid peroxidation and MDA content were significantly increased, and GSH content and T-SOD activity were significantly decreased after exposure to NiCl2. Moreover, NiCl2 increased COX-2 protein levels, decreased SLC7A11 and GPX4 protein levels, and elevated Ptgs2 mRNA levels. Next, the mechanism of Ni-induced ferroptosis was investigated. The results showed that NiCl2 induced autophagy in TCMK-1 cells, which promoted ferroptosis induced by NiCl2. Furthermore, the data of autophagy activation or inhibition experiment showed that autophagy facilitated ferroptosis through the degradation of the iron regulation protein NCOA4 and FTH1. Otherwise, iron chelator DFOM treatment inhibited ferroptosis induced by NiCl2. Finally, ferroptosis inhibitor Fer-1 treatment significantly alleviated cytotoxicity induced by NiCl2. To sum up, our above results showed that ferroptosis is involved in NiCl2-induced nephrotoxicity, and NiCl2 induces autophagy-dependent ferritin degradation, releases iron ions, leads to iron overload, and induces ferroptosis. This study supplies a new theoretical foundation for the study of nickel and renal toxicity.


Assuntos
Ferroptose , Animais , Camundongos , Níquel/toxicidade , Níquel/metabolismo , Ferro/metabolismo , Ferritinas , Autofagia/genética
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