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1.
Cell ; 183(7): 1867-1883.e26, 2020 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-33248023

RESUMO

Biliary atresia (BA) is a severe cholangiopathy that leads to liver failure in infants, but its pathogenesis remains to be fully characterized. By single-cell RNA profiling, we observed macrophage hypo-inflammation, Kupffer cell scavenger function defects, cytotoxic T cell expansion, and deficiency of CX3CR1+effector T and natural killer (NK) cells in infants with BA. More importantly, we discovered that hepatic B cell lymphopoiesis did not cease after birth and that tolerance defects contributed to immunoglobulin G (IgG)-autoantibody accumulation in BA. In a rhesus-rotavirus induced BA model, depleting B cells or blocking antigen presentation ameliorated liver damage. In a pilot clinical study, we demonstrated that rituximab was effective in depleting hepatic B cells and restoring the functions of macrophages, Kupffer cells, and T cells to levels comparable to those of control subjects. In summary, our comprehensive immune profiling in infants with BA had educed that B-cell-modifying therapies may alleviate liver pathology.


Assuntos
Atresia Biliar/imunologia , Atresia Biliar/terapia , Fígado/imunologia , Animais , Antígenos CD20/metabolismo , Linfócitos B/imunologia , Atresia Biliar/sangue , Atresia Biliar/tratamento farmacológico , Biópsia , Receptor 1 de Quimiocina CX3C/metabolismo , Morte Celular , Linhagem Celular , Proliferação de Células , Transdiferenciação Celular , Criança , Pré-Escolar , Estudos de Coortes , Citotoxicidade Imunológica , Modelos Animais de Doenças , Feminino , Humanos , Imunoglobulina G/metabolismo , Lactente , Inflamação/patologia , Células Matadoras Naturais/imunologia , Células de Kupffer/patologia , Fígado/patologia , Cirrose Hepática/sangue , Cirrose Hepática/complicações , Cirrose Hepática/imunologia , Cirrose Hepática/patologia , Depleção Linfocítica , Linfopoese , Masculino , Camundongos Endogâmicos BALB C , Fagocitose , RNA/metabolismo , Rituximab/administração & dosagem , Rituximab/farmacologia , Rituximab/uso terapêutico , Rotavirus/fisiologia , Análise de Célula Única , Células Th1/imunologia , Células Th17/imunologia
2.
Cell ; 179(5): 1160-1176.e24, 2019 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-31730855

RESUMO

Pediatric-onset colitis and inflammatory bowel disease (IBD) have significant effects on the growth of infants and children, but the etiopathogenesis underlying disease subtypes remains incompletely understood. Here, we report single-cell clustering, immune phenotyping, and risk gene analysis for children with undifferentiated colitis, Crohn's disease, and ulcerative colitis. We demonstrate disease-specific characteristics, as well as common pathogenesis marked by impaired cyclic AMP (cAMP)-response signaling. Specifically, infiltration of PDE4B- and TNF-expressing macrophages, decreased abundance of CD39-expressing intraepithelial T cells, and platelet aggregation and release of 5-hydroxytryptamine at the colonic mucosae were common in colitis and IBD patients. Targeting these pathways by using the phosphodiesterase inhibitor dipyridamole restored immune homeostasis and improved colitis symptoms in a pilot study. In summary, comprehensive analysis of the colonic mucosae has uncovered common pathogenesis and therapeutic targets for children with colitis and IBD.


Assuntos
Doenças Inflamatórias Intestinais/patologia , Doenças Inflamatórias Intestinais/terapia , Mucosa Intestinal/patologia , Antígenos CD/metabolismo , Apirase/metabolismo , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Morte Celular/efeitos dos fármacos , Microambiente Celular/efeitos dos fármacos , Criança , Estudos de Coortes , Colo/patologia , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/metabolismo , Dipiridamol/farmacologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Predisposição Genética para Doença , Homeostase/efeitos dos fármacos , Humanos , Imunoglobulina G/sangue , Memória Imunológica , Inflamação/patologia , Doenças Inflamatórias Intestinais/sangue , Doenças Inflamatórias Intestinais/genética , Interferon Tipo I/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Metilprednisolona/farmacologia , Células Mieloides/efeitos dos fármacos , Células Mieloides/metabolismo
3.
Nature ; 615(7950): 50-55, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36859583

RESUMO

The newly discovered nickelate superconductors so far only exist in epitaxial thin films synthesized by a topotactic reaction with metal hydrides1. This method changes the nickelates from the perovskite to an infinite-layer structure by deintercalation of apical oxygens1-3. Such a chemical reaction may introduce hydrogen (H), influencing the physical properties of the end materials4-9. Unfortunately, H is insensitive to most characterization techniques and is difficult to detect because of its light weight. Here, in optimally Sr doped Nd0.8Sr0.2NiO2H epitaxial films, secondary-ion mass spectroscopy shows abundant H existing in the form of Nd0.8Sr0.2NiO2Hx (x ≅ 0.2-0.5). Zero resistivity is found within a very narrow H-doping window of 0.22 ≤ x ≤ 0.28, showing unequivocally the critical role of H in superconductivity. Resonant inelastic X-ray scattering demonstrates the existence of itinerant interstitial s (IIS) orbitals originating from apical oxygen deintercalation. Density functional theory calculations show that electronegative H- occupies the apical oxygen sites annihilating IIS orbitals, reducing the IIS-Ni 3d orbital hybridization. This leads the electronic structure of H-doped Nd0.8Sr0.2NiO2Hx to be more two-dimensional-like, which might be relevant for the observed superconductivity. We highlight that H is an important ingredient for superconductivity in epitaxial infinite-layer nickelates.

4.
EMBO J ; 42(5): e110468, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36647737

RESUMO

Genetic lesions in X-linked inhibitor of apoptosis (XIAP) pre-dispose humans to cell death-associated inflammatory diseases, although the underlying mechanisms remain unclear. Here, we report that two patients with XIAP deficiency-associated inflammatory bowel disease display increased inflammatory IL-1ß maturation as well as cell death-associated caspase-8 and Gasdermin D (GSDMD) processing in diseased tissue, which is reduced upon patient treatment. Loss of XIAP leads to caspase-8-driven cell death and bioactive IL-1ß release that is only abrogated by combined deletion of the apoptotic and pyroptotic cell death machinery. Namely, extrinsic apoptotic caspase-8 promotes pyroptotic GSDMD processing that kills macrophages lacking both inflammasome and apoptosis signalling components (caspase-1, -3, -7, -11 and BID), while caspase-8 can still cause cell death in the absence of both GSDMD and GSDME when caspase-3 and caspase-7 are present. Neither caspase-3 and caspase-7-mediated activation of the pannexin-1 channel, or GSDMD loss, prevented NLRP3 inflammasome assembly and consequent caspase-1 and IL-1ß maturation downstream of XIAP inhibition and caspase-8 activation, even though the pannexin-1 channel was required for NLRP3 triggering upon mitochondrial apoptosis. These findings uncouple the mechanisms of cell death and NLRP3 activation resulting from extrinsic and intrinsic apoptosis signalling, reveal how XIAP loss can co-opt dual cell death programs, and uncover strategies for targeting the cell death and inflammatory pathways that result from XIAP deficiency.


Assuntos
Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Humanos , Apoptose , Caspase 1/genética , Caspase 1/metabolismo , Caspase 3/metabolismo , Caspase 7/metabolismo , Caspase 8/genética , Caspase 8/metabolismo , Morte Celular , Inflamassomos/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Piroptose/fisiologia , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/genética , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismo
5.
Cell Mol Life Sci ; 81(1): 189, 2024 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-38643448

RESUMO

Peritoneal metastasis, the third most common metastasis in colorectal cancer (CRC), has a poor prognosis for the rapid progression and limited therapeutic strategy. However, the molecular characteristics and pathogenesis of CRC peritoneal metastasis are poorly understood. Here, we aimed to elucidate the action and mechanism of adipose-derived stem cells (ADSCs), a prominent component of the peritoneal microenvironment, in CRC peritoneal metastasis formation. Database analysis indicated that ADSCs infiltration was increased in CRC peritoneal metastases, and high expression levels of ADSCs marker genes predicted a poor prognosis. Then we investigated the effect of ADSCs on CRC cells in vitro and in vivo. The results revealed that CRC cells co-cultured with ADSCs exhibited stronger metastatic property and anoikis resistance, and ADSCs boosted the intraperitoneal seeding of CRC cells. Furthermore, RNA sequencing was carried out to identify the key target gene, angiopoietin like 4 (ANGPTL4), which was upregulated in CRC specimens, especially in peritoneal metastases. Mechanistically, TGF-ß1 secreted by ADSCs activated SMAD3 in CRC cells, and chromatin immunoprecipitation assay showed that SMAD3 facilitated ANGPTL4 transcription by directly binding to ANGPTL4 promoter. The ANGPTL4 upregulation was essential for ADSCs to promote glycolysis and anoikis resistance in CRC. Importantly, simultaneously targeting TGF-ß signaling and ANGPTL4 efficiently reduced intraperitoneal seeding in vivo. In conclusion, this study indicates that tumor-infiltrating ADSCs promote glycolysis and anoikis resistance in CRC cells and ultimately facilitate peritoneal metastasis via the TGF-ß1/SMAD3/ANGPTL4 axis. The dual-targeting of TGF-ß signaling and ANGPTL4 may be a feasible therapeutic strategy for CRC peritoneal metastasis.


Assuntos
Neoplasias Colorretais , Neoplasias Peritoneais , Humanos , Neoplasias Peritoneais/genética , Fator de Crescimento Transformador beta1 , Glicólise , Neoplasias Colorretais/genética , Células-Tronco , Microambiente Tumoral , Proteína Smad3/genética , Proteína 4 Semelhante a Angiopoietina/genética
6.
Proc Natl Acad Sci U S A ; 119(20): e2122952119, 2022 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-35561215

RESUMO

SignificanceQuantum anomalous Hall effect (QAHE) and magnetic skyrmion (SK), as two typical topological states in momentum (K) and real (R) spaces, attract much interest in condensed matter physics. However, the interplay between these two states remains to be explored. We propose that the interplay between QAHE and SK may generate an RK joint topological skyrmion (RK-SK), characterized by the SK surrounded by nontrivial chiral boundary states (CBSs). Furthermore, the emerging external field-tunable CBS in RK-SK could create additional degrees of freedom for SK manipulations, beyond the traditional SK. Meanwhile, external field can realize a rare topological phase transition between K and R spaces. Our work opens avenues for exploring unconventional quantum states and topological phase transitions in different spaces.

7.
Oncologist ; 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38530254

RESUMO

BACKGROUND: Atezolizumab plus bevacizumab (atezo-bev) has been recommended for advanced hepatocellular carcinoma (HCC). High-dose external beam radiotherapy (RT) is recognized for its excellent local tumor control. The efficacy and safety of concurrent atezo-bev with RT for highly advanced HCC has been minimally explored. METHODS: In this preliminary retrospective study, we assessed patients with highly advanced HCC, characterized by Vp4 portal vein thrombosis or tumors exceeding 50% of liver volume, who received concurrent atezo-bev and RT (group A). Group A included 13 patients who received proton radiation at a dose of 72.6 GyE in 22 fractions, and one patient who received photon radiation at a dose of 54 Gy in 18 fractions. This group was compared with 34 similar patients treated atezo-bev alone as a control (group B). The primary objectives were to evaluate the objective response rate (ORR), overall survival (OS), and safety. RESULTS: Baseline characteristics were similar between groups, except for a higher incidence of Vp4 portal vein thrombosis in group A (78.6% vs. 21.4%, P = .05). Group A achieved a higher ORR (50.0% vs. 11.8%, P < .01) and a longer OS (not reached vs. 5.5 months, P = .01) after a median follow-up of 5.2 months. Multivariate analysis indicated that concurrent RT independently favored longer OS (hazard ratio: 0.18; 95% CI, 0.05-0.63, P < .01). Group A did not increase any grade adverse events (78.6% vs. 58.8%, P = .19) or severe adverse events of grade ≥ 3 (14.3% vs. 14.7%, P = .97) compared to group B. CONCLUSIONS: The concurrent high-dose external beam radiotherapy appears to safely enhance the effectiveness of atezolizumab plus bevacizumab for highly advanced patients with HCC. Further studies are warranted to confirm these findings.

8.
Anal Chem ; 96(21): 8528-8533, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38728651

RESUMO

In the realm of nanopore sensor technology, an enduring challenge lies in achieving the discerning detection of small biomolecules with a sufficiently high signal-to-noise ratio. This study introduces a method for reliably quantifying the concentration of target small molecules, utilizing tetrahedral DNA nanostructures as surrogates for the captured molecules through a magnetic-bead-based competition substitution mechanism. Magnetic Fe3O4-DNA tetrahedron nanoparticles (MNPs) are incorporated into a nanopore electrochemical system for small-molecule sensing. In the presence of the target, the DNA tetrahedron, featuring an aptamer tail acting as a molecular carrier, detaches from the MNPs due to aptamer deformation. Following removal of the MNPs, the DNA tetrahedron bound to the target traversed the nanopore by applying a positive potential. This approach exhibits various advantages, including heightened sensitivity, selectivity, an improved signal-to-noise ratio (SNR), and robust anti-interference capabilities. Our findings demonstrate that this innovative methodology has the potential to significantly enhance the sensing of various small-molecule targets by nanopores, thereby advancing the sensitivity and dynamic range. This progress holds promise for the development of precise clinical diagnostic tools.


Assuntos
Aptâmeros de Nucleotídeos , DNA , Nanoporos , Nanoestruturas , DNA/química , DNA/análise , Aptâmeros de Nucleotídeos/química , Nanoestruturas/química , Técnicas Eletroquímicas/métodos , Técnicas Biossensoriais/métodos
9.
Mol Psychiatry ; 28(1): 448-462, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36481931

RESUMO

The incubation phenomenon, cue-induced drug craving progressively increasing over prolonged withdrawal, accounts for persistent relapse, leading to a dilemma in the treatment of cocaine addiction. The role of neuronal ensembles activated by initial cocaine experience in the incubation phenomenon was unclear. In this study, with cocaine self-administration (SA) models, we found that neuronal ensembles in the nucleus accumbens shell (NAcSh) showed increasing activation induced by cue-induced drug-seeking after 30-day withdrawal. Inhibition or activation of NAcSh cocaine-ensembles suppressed or promoted craving for cocaine, demonstrating a critical role of NAcSh cocaine-ensembles in incubation for cocaine craving. NAcSh cocaine-ensembles showed a specific increase of membrane excitability and a decrease of inward rectifying channels Kir2.1 currents after 30-day withdrawal. Overexpression of Kir2.1 in NAcSh cocaine-ensembles restored neuronal membrane excitability and suppressed cue-induced drug-seeking after 30-day withdrawal. Expression of dominant-negative Kir2.1 in NAcSh cocaine-ensembles enhanced neuronal membrane excitability and accelerated incubation of cocaine craving. Our results provide a cellular mechanism that the downregulation of Kir2.1 functions in NAcSh cocaine-ensembles induced by prolonged withdrawal mediates the enhancement of ensemble membrane excitability, leading to incubation of cocaine craving.


Assuntos
Transtornos Relacionados ao Uso de Cocaína , Cocaína , Animais , Cocaína/farmacologia , Cocaína/metabolismo , Transtornos Relacionados ao Uso de Cocaína/metabolismo , Fissura/fisiologia , Sinais (Psicologia) , Regulação para Baixo , Comportamento de Procura de Droga/fisiologia , Núcleo Accumbens/metabolismo , Autoadministração
10.
Biol Lett ; 20(6): 20240062, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38923948

RESUMO

Diatom cell-size composition is an indicator of aquatic environmental changes but has been rarely investigated, especially in semi-terrestrial peatlands. In this study, both taxonomic composition and cell-size composition of diatoms were analysed in 41 samples from two montane peatlands, northeastern China. Redundancy analyses revealed that diatom taxonomic composition was significantly related to the depth to the water table (DWT) and Ca2+, while cell-size composition was significantly associated with DWT and Si. DWT was the most important factor and its sole effect explained 26.2% and 17.9% of the total variance in taxonomic composition and cell-size composition, respectively. Accordingly, diatom-based water-table transfer functions were developed based on taxonomic composition and cell-size composition, respectively. The maximum-likelihood (ML) model based on diatom taxonomic composition had the best performance, with a correlation coefficient value (R2) of 0.78 and the root mean squared error of prediction (RMSEP) of 6.66 cm. The ML model based on cell-size composition had similar performance, with an R2 of 0.78 and the RMSEP of 6.87 cm, suggesting that diatom cell-size composition can be a new quantitative means to track past water-table changes. This method requires further appraisal with palaeoecological data but offers a new option that deserves exploration.


Assuntos
Diatomáceas , Diatomáceas/classificação , Diatomáceas/citologia , China , Água Subterrânea , Áreas Alagadas , Solo , Tamanho Celular
11.
J Pathol ; 260(4): 402-416, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37272544

RESUMO

Homeobox genes include HOX and non-HOX genes. HOX proteins play fundamental roles during ontogenesis by interacting with other non-HOX gene-encoded partners and performing transcriptional functions, whereas aberrant activation of HOX family members drives tumorigenesis. In this study, gastric cancer (GC) expression microarray data indicated that HOXB9 is a prominent upregulated HOX member in GC samples significantly associated with clinical outcomes and advanced TNM stages. However, the functional role of HOXB9 in GC remains contradictory in previous reports, and the regulatory mechanisms are elusive. By in silico and experimental analyses, we found that HOXB9 was upregulated by a vital cell cycle-related transcription factor, E2F1. Depleting HOXB9 causes G1-phase cell cycle arrest by downregulating CDK6 and a subset of cell cycle-related genes. Meanwhile, HOXB9 contributes to cell division and maintains the cytoskeleton in GC cells. We verified that HOXB9 interacts with PBX2 to form a heterodimer, which transcriptionally upregulates CDK6. Knocking down CDK6 can phenocopy the tumor-suppressive effects caused by HOXB9 depletion. Blocking HOXB9 can enhance the anti-tumor effect of CDK6 inhibitors. In conclusion, we elucidate the oncogenic role of HOXB9 in GC and reveal CDK6 as its potent downstream effector. The E2F1-HOXB9/PBX2-CDK6 axis represents a novel mechanism driving gastric carcinogenesis and conveys prognostic and therapeutic implications. © 2023 The Pathological Society of Great Britain and Ireland.


Assuntos
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patologia , Genes Homeobox , Linhagem Celular Tumoral , Carcinogênese/patologia , Fatores de Transcrição/genética , Transformação Celular Neoplásica/genética , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Regulação Neoplásica da Expressão Gênica , Proliferação de Células/fisiologia , Proteínas Proto-Oncogênicas/genética , Fator de Transcrição E2F1/genética , Fator de Transcrição E2F1/metabolismo
12.
Neuroradiology ; 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38844696

RESUMO

This retrospective study examined the clinical outcomes and complications in 6 cases of compound Meige's syndrome, presenting with blepharospasm and masticatory muscle spasm, following treatment with CT-guided radiofrequency ablation targeting bilateral facial nerves and mandibular branches of the trigeminal nerve. After the operation, the symptoms of eyelid spasm and masticatory muscle spasm resolved, but mild facial paralysis and numbness of mandibular nerve innervation persisted. Follow-up for 4-28 months showed that the symptoms of facial paralysis resolved within 2-5 (3.17 ± 0.94) months after the operation, whereas the numbness in the mandibular region persisted, accompanied by a decrease in masticatory function. During the follow-up period, none of the 6 patients experienced a recurrence of Meige's syndrome. These findings suggest that CT-guided radiofrequency ablation of the bilateral facial nerve and mandibular branches of the trigeminal nerve may offer a promising approach to treating compound Meige's syndrome.

13.
Support Care Cancer ; 32(3): 203, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38430411

RESUMO

PURPOSE: Nasopharyngeal carcinoma (NPC) patients may experience symptom distress and depression during and after radiation therapy, which negatively impacts quality of life (QOL). We sought to identify trajectories of symptom distress, depression, social support, and QOL in patients with NPC receiving intensity-modulated radiation therapy (IMRT) vs intensity-modulated proton therapy (IMPT). METHODS: A multicenter prospective longitudinal study recruited NPC patients from two leading medical centers in Taiwan. The 121 NPC patients were followed from before RT (T0), at 4 weeks after beginning RT (T1), at 6 weeks of RT or the end of treatment (T2), and at 4 weeks post-RT (T3). Generalized estimating equation analysis was used to identify the factors related to QOL. RESULTS: Patients' symptom distress and depression increased from T0, peaked at T2, and decreased at T3. Physical-QOL and psychosocial-QOL decreased from T0 to T2, then increased by T3. Patients who had early-stage cancer, received a lower RT dose, had less symptom distress, and had less depression were more likely to have better QOL. Greater physical-QOL was associated with IMPT receipt, higher education level, early cancer stage, lower radiation dose, less symptom distress, and less depression. Patients who had good physical performance, received a lower radiation dose, had less symptom distress, and had less depression were more likely to have better psychosocial-QOL. CONCLUSION: Radiation dose, symptom distress, and depression were the most important factors affecting QOL in patients with NPC. Understanding the factors associated with the trajectory of QOL can guide care during radiation treatment.


Assuntos
Neoplasias Nasofaríngeas , Terapia com Prótons , Radioterapia de Intensidade Modulada , Humanos , Carcinoma Nasofaríngeo/radioterapia , Radioterapia de Intensidade Modulada/efeitos adversos , Qualidade de Vida , Estudos Longitudinais , Estudos Prospectivos , Neoplasias Nasofaríngeas/radioterapia , Neoplasias Nasofaríngeas/patologia
14.
Appl Opt ; 63(6): A24-A31, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38437354

RESUMO

Rapid testing of cement raw meal plays a crucial role in the cement production process, so there is an urgent need for a fast and accurate testing method. In this paper, a method based on the Savitzky-Golay (SG) smoothing and sample set partitioning based on joint x-y distance (SPXY) spectral data pre-processing is proposed to improve the accuracy of the laser-induced breakdown spectroscopy (LIBS) technique for quantitative analysis of cement raw meal components. Firstly, the spectral data is denoised by SG smoothing, which effectively reduces the noise and baseline variations in the spectra. Then, the denoised data is divided into sample sets by combining the SPXY sample division method, which improves the efficiency of data analysis. Finally, the delineated data set is modeled for quantitative analysis by a back-propagation (BP) neural network. Compared to the modeling effect of the four oxide contents of CaO, S i O 2, A l 2 O 3, and F e 2 O 3 in the Hold-Out method, the correlation coefficient (R) was improved by 26%, 10%, 17%, and 4%, respectively. The root mean square error (RMSE) was reduced by 47%, 33%, 43%, and 21%, respectively. The mean absolute percentage error (MAPE) was reduced by 63%, 60%, 36%, and 51%, respectively. The results show that there is a significant improvement in the model effect, which can effectively improve the accuracy of quantitative analysis of cement raw meal composition by LIBS. This is of great significance for the real-time detection of cement raw meal composition analysis.

15.
Exp Parasitol ; 259: 108712, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38336093

RESUMO

Chicken coccidiosis, which caused by Eimeria spp, is a parasitic protozoal disease. At present, control measures of this disease depend mainly on anticoccidial drugs and live vaccines. But these control strategies have drawbacks such as drug resistance and limitations in live vaccines production. Therefore, novel control approaches are urgently need to study to control this disease effectively. In this study, the function and characteristics of the pyrroline-5-carboxylate reductase of Eimeria tenella (EtPYCR) protein were preliminary analyzed. The transcription and translation level were analyzed by using qPCR and Western blot. The results showed that the mRNA transcription and translation levels of EtPYCR were higher in unsporulated oocysts (UO) and second generation merozoites (Mrz) than that in sporulated oocysts (SO) and sporozoites. Enzyme activity showed that the enzyme activity of EtPYCR was also higher in the UO and Mrz than that in the SO and sporozoites. Immunofluorescence localization showed EtPYCR was mainly located on the top of sporozoites and the whole cytoplasm and surface of Mrz. The secretion assay indicated that EtPYCR was secretion protein, but not from micronemes. Invasion inhibition assay showed that rabbit anti-rEtPYCR polyclonal antibodies can effectively inhibit sporozoite invasion of DF-1 cells. These results showed that EtPYCR possess several important roles that separate and distinct from its conversion 1-pyrroline-5-carboxylate (P5C) into proline and maybe involved in the host cell invasion and development of parasites in host cells.


Assuntos
Coccidiose , Eimeria tenella , Doenças das Aves Domésticas , Pirróis , Vacinas , Animais , Coelhos , Proteínas de Protozoários , Clonagem Molecular , Galinhas/parasitologia , Esporozoítos , Oocistos , Coccidiose/parasitologia , Oxirredutases/metabolismo , Doenças das Aves Domésticas/parasitologia
16.
Proc Natl Acad Sci U S A ; 118(19)2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-33952701

RESUMO

To efficiently integrate cutting-edge terahertz technology into compact devices, the highly confined terahertz plasmons are attracting intensive attention. Compared to plasmons at visible frequencies in metals, terahertz plasmons, typically in lightly doped semiconductors or graphene, are sensitive to carrier density (n) and thus have an easy tunability, which leads to unstable or imprecise terahertz spectra. By deriving a simplified but universal form of plasmon frequencies, here, we reveal a unified mechanism for generating unusual n-independent plasmons (DIPs) in all topological states with different dimensions. Remarkably, we predict that terahertz DIPs can be excited in a two-dimensional nodal line and one-dimensional nodal point systems, confirmed by the first-principle calculations on almost all existing topological semimetals with diverse lattice symmetries. Besides n-independence, the feature of Fermi velocity and degeneracy factor dependencies in DIPs can be applied to design topological superlattice and multiwalled carbon nanotube metamaterials for broadband terahertz spectroscopy and quantized terahertz plasmons, respectively. Surprisingly, high spatial confinement and quality factor, also insensitive to n, can be simultaneously achieved in these terahertz DIPs. Our findings pave the way for developing topological plasmonic devices for stable terahertz applications.

17.
Proc Natl Acad Sci U S A ; 118(31)2021 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-34330835

RESUMO

Electromagnetic radiation (EMR) in the environment has increased sharply in recent decades. The effect of environmental EMR on living organisms remains poorly characterized. Here, we report the impact of wireless-range EMR on the sleep architecture of mouse. Prolonged exposure to 2.4-GHz EMR modulated by 100-Hz square pulses at a nonthermal output level results in markedly increased time of wakefulness in mice. These mice display corresponding decreased time of nonrapid eye movement (NREM) and rapid eye movement (REM). In contrast, prolonged exposure to unmodulated 2.4-GHz EMR at the same time-averaged output level has little impact on mouse sleep. These observations identify alteration of sleep architecture in mice as a specific physiological response to prolonged wireless-range EMR exposure.


Assuntos
Fenômenos Eletromagnéticos , Sono/efeitos da radiação , Vigília/efeitos da radiação , Tecnologia sem Fio , Animais , Camundongos
18.
Ecotoxicol Environ Saf ; 270: 115878, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38150748

RESUMO

Aluminum (Al) exposure has been linked to the development of a variety of neurodegenerative diseases. However, whether m6A RNA methylation participated in Al-induced neurotoxicity remain to be defined. In this study, mice were administrated with aluminum-lactate at dose of 220 mg/kg. bw by gavage for 3 months. Meanwhile, the primary hippocampal neurons were isolated and treated with 0, 50, 100, 150 µM aluminum-lactate, respectively for 7 days. Al exposure caused neuronal shrinkage, decreased Nissl bodies, and increased apoptosis. In accordance, in vitro studies also showed that Al exposure led to neuronal apoptosis in a dose-dependent manner, together with the decline in m6A RNA methylation levels. Moreover, the mRNA expression of Mettl3, Mettl14, Fto, and Ythdf2 were decreased upon Al exposure. Notably, the protein expression of METTL3 was dramatically down-regulated by 42% and 35% in Al-treated mice and neurons, suggesting METTL3 might exert a crucial role in Al-induced neurotoxicity. We next established a mouse model with hippocampus-specific overexpressing of Mettl3 gene to confirm the regulatory role of RNA methylation and found that METTL3 overexpression relieved the neurological injury induced by Al. The integrated MeRIP-seq and RNA-seq analysis elucidated that 631 genes were differentially expressed at both m6A RNA methylation and mRNA expression. Notably, EGFR tyrosine kinase inhibitor resistance, Rap1 signaling pathway, protein digestion and absorption might be involved in Al-induced neurotoxicity. Moreover, VEGFA, Thbs1, and PDGFB might be the central molecules. Collectively, our findings provide the novel sight into the role of m6A RNA methylation in neurodegenerative disease induced by Al.


Assuntos
Alumínio , Doenças Neurodegenerativas , Camundongos , Animais , Alumínio/toxicidade , Alumínio/metabolismo , Metilação de RNA , Metiltransferases/genética , Metiltransferases/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Lactatos , RNA/metabolismo
19.
Small ; 19(34): e2301516, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37086123

RESUMO

Proton exchange membrane water electrolyzer (PEMWE) is a green hydrogen production technology that can be coupled with intermittent power sources such as wind and photoelectric power. To achieve cost-effective operations, low noble metal loading on the anode catalyst layer is desired. In this study, a catalyst with RuO2 nanorods coated outside SnO2 nanocubes is designed, which forms continuous networks and provides high conductivity. This allows for the reduction of Ru contents in catalysts. Furthermore, the structure evolutions on the RuO2 surface are carefully investigated. The etched RuO2 surfaces are seen as the consequence of Co leaching, and theoretical calculations demonstrate that it is more effective in driving oxygen evolution. For electrochemical tests, the catalysts with 23 wt% Ru exhibit an overpotential of 178 mV at 10 mA cm-2 , which is much higher than most state-of-art oxygen evolution catalysts. In a practical PEMWE, the noble metal Ru loading on the anode side is only 0.3 mg cm-2 . The cell achieves 1.61 V at 1 A cm-2 and proper stability at 500 mA cm-2 , demonstrating the effectiveness of the designed catalyst.

20.
Nat Mater ; 21(10): 1116-1120, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35982306

RESUMO

In materials science, much effort has been devoted to the reproduction of superconductivity in chemical compositions, analogous to cuprate superconductors since their discovery over 30 years ago. This approach was recently successful in realising superconductivity in infinite-layer nickelates1-6. Although differing from cuprates in electronic and magnetic properties, strong Coulomb interactions suggest that infinite-layer nickelates have a propensity towards various symmetry-breaking orders that populate cuprates7-10. Here we report the observation of charge density waves (CDWs) in infinite-layer NdNiO2 films using Ni L3 resonant X-ray scattering. Remarkably, CDWs form in Nd 5d and Ni 3d orbitals at the same commensurate wavevector (0.333, 0) reciprocal lattice units, with non-negligible out-of-plane dependence and an in-plane correlation length of up to ~60 Å. Spectroscopic studies reveal a strong connection between CDWs and Nd 5d-Ni 3d orbital hybridization. Upon entering the superconducting state at 20% Sr doping, the CDWs disappear. Our work demonstrates the existence of CDWs in infinite-layer nickelates with a multiorbital character distinct from cuprates, which establishes their low-energy physics.

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