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1.
Chemistry ; : e202402562, 2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39210677

RESUMEN

The electrochemical nitrogen reduction reaction (NRR) to synthesize ammonia (NH3) is considered as a promising method due to its approvable advantages of zero-pollution emission, feasible reaction proceedings, good safety and easy management. The multiple efforts have been devoted to the exploration of earth-abundant-element-based nanomaterials as high-efficiency electrocatalysts for realizing their industrial applications. Among these, the Ni-based nanomaterials is prioritized as an attractive non-noble-metal electrocatalysts for catalyzing NRR because they are earth-abundance and exceedingly easy to synthesize as well as also delivers the potential of high electrocatalytic activity and durability. In this review, after briefly elucidating the underlying mechanisms of NRR during the electrochemical process, we systematically sum up the recent research progress in representative Ni-based electrocatalysts, including monometallic Ni-based nanomaterials, bimetallic Ni-based nanomaterials, polymetallic Ni-based nanomaterials, etc. In particular, we discuss the effects of physicochemical properties, such as phases, crystallinity, morphology, composition, defects, heteroatom doping, and strain engineering, on the comprehensive performance of the abovementioned electrocatalysts, with the aim of establishing the nanostructure-function relationships of the electrocatalysts. In addition, the promising directions of Ni-based electrocatalysts for NRR are also pointed out and highlighted. The generic approach in this review may expand the frontiers of NRR and provides the inspiration for developing high-efficiently Ni-based electrocatalysts.

2.
Appl Opt ; 62(7): 1745-1752, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-37132921

RESUMEN

Modified near-ballistic uni-traveling-carrier photodiodes with improved overall performances were studied theoretically and experimentally. A bandwidth up to 0.2 THz with a 3 dB bandwidth of 136 GHz and large output power of 8.22 dBm (99 GHz) under the -2V bias voltage were obtained. The device exhibits good linearity in the photocurrent-optical power curve even at large input optical power, with a responsivity of 0.206 A/W. Physical explanations for the improved performances have been made in detail. The absorption layer and the collector layer were optimized to retain a high built-in electric field around the interface, which not only ensures the smoothness of the band structure but also facilitates the near-ballistic transmission of uni-traveling carriers. The obtained results may find potential applications in future high-speed optical communication chips and high-performance terahertz sources.

3.
Sensors (Basel) ; 23(4)2023 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-36850660

RESUMEN

Anomaly detection of hyperspectral remote sensing data has recently become more attractive in hyperspectral image processing. The low-rank and sparse matrix decomposition-based anomaly detection algorithm (LRaSMD) exhibits poor detection performance in complex scenes with multiple background edges and noise. Therefore, this study proposes a weighted sparse hyperspectral anomaly detection method. First, using the idea of matrix decomposition in mathematics, the original hyperspectral data matrix is reconstructed into three sub-matrices with low rank, small sparsity and representing noise, respectively. Second, to suppress the noise interference in the complex background, we employed the low-rank, background image as a reference, built a local spectral and spatial dictionary through the sliding window strategy, reconstructed the HSI pixels of the original data, and extracted the sparse coefficient. We proposed the sparse coefficient divergence evaluation index (SCDI) as a weighting factor to weight the sparse anomaly map to obtain a significant anomaly map to suppress the background edge, noise, and other residues caused by decomposition, and enhance the abnormal target. Finally, abnormal pixels are segmented based on the adaptive threshold. The experimental results demonstrate that, on a real-scene hyperspectral dataset with a complicated background, the proposed method outperforms the existing representative algorithms in terms of detection performance.

4.
Environ Microbiol ; 24(12): 6524-6538, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36260054

RESUMEN

The cyclic adenosine monophosphate-protein kinase A (cAMP-PKA) signalling pathway is evolutionarily conserved in eukaryotes and plays a crucial role in defending against external environmental challenges, which can modulate the cellular response to external stimuli. Arthrobotrys oligospora is a typical nematode-trapping fungus that specializes in adhesive networks to kill nematodes. To elucidate the biological roles of the cAMP-PKA signalling pathway, we characterized the orthologous adenylate cyclase AoAcy, a regulatory subunit (AoPkaR), and two catalytic subunits (AoPkaC1 and AoPkaC2) of PKA in A. oligospora by gene disruption, transcriptome, and metabolome analyses. Deletion of Aoacy significantly reduced the levels of cAMP and arthrobotrisins. Results revealed that Aoacy, AopkaR, and AopkaC1 were involved in hyphal growth, trap morphogenesis, sporulation, stress resistance, and autophagy. In addition, Aoacy and AopkaC1 were involved in the regulation of mitochondrial morphology, thereby affecting energy metabolism, whereas AopkaC2 affected sporulation, nuclei, and autophagy. Multi-omics results showed that the cAMP-PKA signalling pathway regulated multiple metabolic and cellular processes. Collectively, these data highlight the indispensable role of cAMP-PKA signalling pathway in the growth, development, and pathogenicity of A. oligospora, and provide insights into the regulatory mechanisms of signalling pathways in sporulation, trap formation, and lifestyle transition.


Asunto(s)
Ascomicetos , Nematodos , Animales , Ascomicetos/genética , Nematodos/microbiología , AMP Cíclico/metabolismo , Morfogénesis , Autofagia/genética
5.
Opt Lett ; 45(4): 827, 2020 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-32058480

RESUMEN

This publisher's note contains corrections to Opt. Lett.44, 2586 (2019)OPLEDP0146-959210.1364/OL.44.002586.

6.
Opt Lett ; 44(10): 2586-2589, 2019 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-31090738

RESUMEN

In this Letter, we report a graphene-based hybrid plasmonic modulator (GHPM) realized by employing the electro-absorption effect of graphene. The simulation results show that the modulation efficiency of GHPM, i.e., extinction ratio per length, can be as large as 0.417 dB/µm, which is more than twice as much as that of recently presented graphene-on-silicon modulator. It was found that the improvement in modulation efficiency is mainly due to the enhancement of the overlap between graphene and the mode field in GHPM. A prototype of GHPM was fabricated. The measurement results showed that the GHPM can work in a broadband from 1530 to 1570 nm and an improved modulation efficiency of 1.08 dB (at 30 µm). Finally, we have discussed the factors that influence the modulation efficiency. Our proof-of-concept design may promote the development of on-chip graphene-based plasmonic devices.

7.
Heliyon ; 10(18): e37441, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39309950

RESUMEN

Mining strip coal pillars left due to strip mining is important to resource-exhausted coal mines in eastern China. Backfilling mining is an effective means to mine strip coal pillars, which could decrease high stress and high energy release. However, materials with super-high water content were not widely applied in deeply isolated coal pillar mining due to lower strength characteristics and durability. In the paper, taking panel c8301 as engineering background, theoretical analysis, numerical simulation, and field monitoring were used to study the feasibility and application effect of the super-high-water backfilling technology in deep isolated coal pillar mining. The results showed that: (1) Panel c8301 is a strip-filling working face with insufficient mining on both sides, and the mining of the panel will trigger the rebalancing of the overlying rock structure on both sides, which increases the rock burst risk. (2) Simulation results indicate that the super-high-water filling method, in comparison to the traditional caving method, significantly reduces peak stress and elastic energy from 112.3 MPa to 4.6 × 106 J to 79.2 MPa and 2.23 × 106 J, respectively. This represents reductions of 29.6 % and 51.5 %, effectively mitigating the impact of mining activities on overburden movement. (3) On-site measurement data confirmed that the measured equivalent mining height was 1.25 m. The total number of microseisms and the amount of released energy decreased significantly, More specifically, three big energy release instances (>1.8 × 105 J) were recorded during the first roof weighting stage and panel in square meters. Super-high-water filling technology has achieved remarkable results in the mining of strip coal pillars and has significant application prospects.

8.
Front Neurol ; 14: 1201964, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37492853

RESUMEN

A Solitary Fibrous Tumor (SFT) is a rare, aggressive, and metastasis- and recurrence- prone mesenchymal tumor. In this case report and review, we describe a rare instance of intracranial SFT, discovered for the first time. It was discovered in 2008 and following total surgical removal, the pathology was categorized as hemangiopericytoma cell tumor (HPC) at the time by WHO tumor criteria. An imaging review 8 months after surgery revealed a tumor recurrence: combined radiation and gamma-knife therapy was continued throughout this time. The tumor did not metastasis until June 2018 when it presented in the pancreas with ruptured bleeding and a postoperative pathology was suggestive of SFT. Fortunately, the patient is still alive nearly 3 years after the 2020 surgery, after staged surgical resection and combined multimedia therapy, with no imaging or clinical evidence of a recurrent intracranial primary lesions. To our knowledge, there is no previous record of using a combined treatment modality for Intracranial Solitary Fibrous Tumor (ISFT). Combined with an account of the patient's experience, we empirically describe a combined approach with a preference for gross-total resection (GTR), supplemented by multimodal assistance with stereotactic (radiotherapy), gamma knife (GK), molecular targeting, and immunization for patients admitted acutely, with accurate preoperative identification and aggressive management after intraoperative case response to maximize treatment of recurrent ISFT and improve prognosis. We recommend multimodal management for SFT with prolonged-term recurrence and metastases, both for the control benefits of GTR, RT, or GK for local recurrence and for the positive prognosis of targeted and immune metastases.

9.
BMC Complement Med Ther ; 23(1): 44, 2023 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-36765346

RESUMEN

BACKGROUND: Chinese medicine usually acts as "multi-ingredients, multi-targets and multi-pathways" on complex diseases, and these action modes reflect the coordination and integrity of the treatment process with traditional Chinese medicine (TCM). System pharmacology is developed based on the cross-disciplines of directional pharmacology, system biology, and mathematics, has the characteristics of integrity and synergy in the treatment process of TCM. Therefore, it is suitable for analyzing the key ingredients and mechanisms of TCM in treating complex diseases. Intracerebral Hemorrhage (ICH) is one of the leading causes of death in China, with the characteristics of high mortality and disability rate. Bring a significant burden on people and society. An increasing number of studies have shown that Chinese medicine prescriptions have good advantages in the treatment of ICH, and Ditan Decoction (DTT) is one of the commonly used prescriptions in the treatment of ICH. Modern pharmacological studies have shown that DTT may play a therapeutic role in treating ICH by inhibiting brain inflammation, abnormal oxidative stress reaction and reducing neurological damage, but the specific key ingredients and mechanism are still unclear. METHODS: To solve this problem, we established PPI network based on the latest pathogenic gene data of ICH, and CT network based on ingredient and target data of DTT. Subsequently, we established optimization space based on PPI network and CT network, and constructed a new model for node importance calculation, and proposed a calculation method for PES score, thus calculating the functional core ingredients group (FCIG). These core functional groups may represent DTT therapy for ICH. RESULTS: Based on the strategy, 44 ingredients were predicted as FCIG, results showed that 80.44% of the FCIG targets enriched pathways were coincided with the enriched pathways of pathogenic genes. Both the literature and molecular docking results confirm the therapeutic effect of FCIG on ICH via targeting MAPK signaling pathway and PI3K-Akt signaling pathway. CONCLUSIONS: The FCIG obtained by our network pharmacology method can represent the effect of DTT in treating ICH. These results confirmed that our strategy of active ingredient group optimization and the mechanism inference could provide methodological reference for optimization and secondary development of TCM.


Asunto(s)
Farmacología en Red , Fosfatidilinositol 3-Quinasas , Humanos , Simulación del Acoplamiento Molecular , Medicina Tradicional China , Hemorragia Cerebral/tratamiento farmacológico
10.
Front Neurol ; 14: 1163990, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37351267

RESUMEN

As radiation therapy is increasingly utilized in the treatment of cancer, neuropathic pain (NP) is a common radiotherapy-related adverse effect and has a significant impact on clinical outcomes negatively. However, despite an improved understanding of neuropathic pain management, pain is often undertreated in patients with cancer. Herein, we reported two cases with radiotherapy-related neuropathic pain (RRNP) who presented a positive reaction to acupuncture. Patient 1 (a 73-year-old woman) with gynecologic cancer complained of burning and electric shock-like pain in the lower limb after radiotherapy. With the accepted combination of acupuncture and drugs, the pain was alleviated completely in 8 weeks. Patient 2 (a 64-year-old woman) accepted acupuncture in the absence of medication because of her inability to tolerate the adverse events of anticonvulsant drugs. She achieved remission of pain 4 weeks later. The results of this study showed that acupuncture might be promising for controlling the RRNP in patients with cancer, especially who were intolerant or unresponsive to medications.

11.
BMC Complement Med Ther ; 22(1): 103, 2022 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-35413898

RESUMEN

BACKGROUND: Chinese herbal medicine (CHM) is characterized by "multi- compounds, multi-targets and multi-pathway", which has advanced benefits for preventing and treating complex diseases, but there still exists unsolved issues, mainly include unclear material basis and underlying mechanism of prescription. Integrated pharmacology is a hot cross research area based on system biology, mathematics and poly-pharmacology. It can systematically and comprehensively investigate the therapeutic reaction of compounds or drugs on pathogenic genes network, and is especially suitable for the study of complex CHM systems. Intracerebral Hemorrhage (ICH) is one of the main causes of death among Chinese residents, which is characterized with high mortality and high disability rate. In recent years, the treatment of ICH by CHM has been deeply researched. Xue Fu Zhu Yu Decoction (XFZYD), one of the commonly used prescriptions in treating ICH at clinic level, has not been clear about its mechanism. METHODS: Here, we established a strategy, which based on compounds-targets, pathogenetic genes, network analysis and node importance calculation. Using this strategy, the core compounds group (CCG) of XFZYD was predicted and validated by in vitro experiments. The molecular mechanism of XFZYD in treating ICH was deduced based on CCG and their targets. RESULTS: The results show that the CCG with 43 compounds predicted by this model is highly consistent with the corresponding Compound-Target (C-T) network in terms of gene coverage, enriched pathway coverage and accumulated contribution of key nodes at 89.49%, 88.72% and 90.11%, respectively, which confirmed the reliability and accuracy of the effective compound group optimization and mechanism speculation strategy proposed by us. CONCLUSIONS: Our strategy of optimizing the effective compound groups and inferring the mechanism provides a strategic reference for explaining the optimization and inferring the molecular mechanism of prescriptions in treating complex diseases of CHM.


Asunto(s)
Medicamentos Herbarios Chinos , Hemorragia Cerebral/tratamiento farmacológico , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico , Humanos , Medicina Tradicional China/métodos , Reproducibilidad de los Resultados
12.
Front Pharmacol ; 13: 1042756, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36793921

RESUMEN

Introduction: Cytochrome P450 (CYP) 3A4 is a major drug metabolizing enzyme for corticosteroids (CS). Epimedium has been used for asthma and variety of inflammatory conditions with or without CS. It is unknown whether epimedium has an effect on CYP 3A4 and how it interacts with CS. We sought to determine the effects of epimedium on CYP3A4 and whether it affects the anti-inflammatory function of CS and identify the active compound responsible for this effect. Methods: The effect of epimedium on CYP3A4 activity was evaluated using the Vivid CYP high-throughput screening kit. CYP3A4 mRNA expression was determined in human hepatocyte carcinoma (HepG2) cells with or without epimedium, dexamethasone, rifampin, and ketoconazole. TNF-α levels were determined following co-culture of epimedium with dexamethasone in a murine macrophage cell line (Raw 264.7). Active compound (s) derived from epimedium were tested on IL-8 and TNF-α production with or without corticosteroid, on CYP3A4 function and binding affinity. Results: Epimedium inhibited CYP3A4 activity in a dose-dependent manner. Dexamethasone enhanced the expression of CYP3A4 mRNA, while epimedium inhibited the expression of CYP3A4 mRNA and further suppressed dexamethasone enhancement of CYP3A4 mRNA expression in HepG2 cells (p < 0.05). Epimedium and dexamethasone synergistically suppressed TNF-α production by RAW cells (p < 0.001). Eleven epimedium compounds were screened by TCMSP. Among the compounds identified and tested only kaempferol significantly inhibited IL-8 production in a dose dependent manner without any cell cytotoxicity (p < 0.01). Kaempferol in combination with dexamethasone showed complete elimination of TNF-α production (p < 0.001). Furthermore, kaempferol showed a dose dependent inhibition of CYP3A4 activity. Computer docking analysis showed that kaempferol significantly inhibited the catalytic activity of CYP3A4 with a binding affinity of -44.73kJ/mol. Discussion: Inhibition of CYP3A4 function by epimedium and its active compound kaempferol leads to enhancement of CS anti-inflammatory effect.

13.
Rapid Commun Mass Spectrom ; 24(23): 3413-8, 2010 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-21072796

RESUMEN

A rapid and reliable method has been optimized and established for the analysis of the metabolites from a marine actinomycete by high-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight mass spectrometry (HPLC/QTOF MS/MS). From MS/MS spectra, the product ions of [M + H](+) were recorded to provide abundant structural information of the mother nucleus and peptide moieties. Using the QTOF MS/MS and in-source collision-induced dissociation (in-source CID) techniques, three main metabolites including actinomycin D, actinomycin V and actinomycin I were determined and characterized by elemental compositions of precursor and product ions (<7 ppm). Additionally, this method provided information about the compositions of the peptide residues and the sequences of the amino acid from a series of fragment ions. It proved useful for the identification of the metabolites in marine samples which have similar structures especially when there were no reference compounds available.


Asunto(s)
Actinobacteria/química , Actinobacteria/metabolismo , Antibióticos Antineoplásicos/química , Cromatografía Líquida de Alta Presión/métodos , Dactinomicina/química , Agua de Mar/microbiología , Espectrometría de Masas en Tándem/métodos , Actinobacteria/aislamiento & purificación , Antibióticos Antineoplásicos/metabolismo , Dactinomicina/análogos & derivados , Dactinomicina/metabolismo , Células Hep G2 , Humanos , Estructura Molecular , Espectrometría de Masa por Ionización de Electrospray/métodos
14.
Zhonghua Gan Zang Bing Za Zhi ; 17(7): 540-3, 2009 Jul.
Artículo en Zh | MEDLINE | ID: mdl-19912691

RESUMEN

OBJECTIVE: To explore the clinical and pathological features of liver injury in adults with acquired rubella. METHODS: Thirty-six adult patients with acquired rubella (AAR) were enrolled in this study, the liver functions were dynamically analyzed, liver biopsy was done in two patients. RESULTS: Liver injury was found in 77.8% of the 36 patients, with slight elevation of ALT and/or AST. The highest incidence and the most serious liver injury occurred in the period of 6-10d after vanishing of the rashes. Viral inclusion bodies were found in the liver specimen, with complete histological architecture but slight inflammation. The mean hospitalization days of AAR accompanied with liver injury and without liver injury were 18.2 days, 7.8 days, respectively (u=3.596>1.96, P<0.05). CONCLUSION: High incidence of liver injury is observed in the adult patients with acquired rubella occurred in recent years, usually exhibited by mild liver injury with slight elevation of ALT. The elevation of AST or jaundice may indicate more serious liver injury, and these patients should be given active treatment to prevent acute liver failure. Liver injury may prolong the course of rubella patients.


Asunto(s)
Alanina Transaminasa/sangre , Hepatopatías/etiología , Hepatopatías/patología , Hígado/patología , Rubéola (Sarampión Alemán)/complicaciones , Adolescente , Adulto , Aspartato Aminotransferasas/sangre , Bilirrubina/sangre , Biopsia con Aguja , Femenino , Humanos , Hepatopatías/sangre , Hepatopatías/epidemiología , Pruebas de Función Hepática , Masculino , Mitocondrias Hepáticas/patología , Pronóstico , Índice de Severidad de la Enfermedad , Adulto Joven
15.
Int J Clin Exp Med ; 7(10): 3410-4, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25419376

RESUMEN

OBJECTIVE: To investigate the clinicopathological characteristics, diagnosis and differential diagnosis, and treatment of xeroderma pigmentosum associated with keratoacanthoma in an infant. METHODS: The clinical manifestations of xeroderma pigmentosum associated with keratoacanthoma were assessed in an 18-month old boy. The morphological and histological features of the lesions were examined by light microscopy. RESULTS: An 18-month old boy was admitted with unequal size, irregularly shaped brown spots, patches and depigmentation spots on his face. A well-circumscribed hemispherical mass measuring 3 cm × 3 cm with smooth surface and brown patches was observed beneath his left lower eyelid. Light microscopic examination of the skin lesions revealed epidermal hyperkeratosis, chronic inflammatory infiltration of the superficial dermal layer, and increases in melanocytes and melanin in the basal layer. Scanning microscopy showed that the mass beneath the left lower eyelid was cup-shaped, consisting of proliferating squamous cells with a central keratin plug. The squamous epithelium was acanthotic with hypergranulosis. The adjacent epidermis formed exophytic projections resulting in a silhouette likened to lips. An associated inflammatory reaction was observed within the stroma surrounding the mass. The patient was treated with a combination of antioxidant drugs, keeping the child from light and surgical excision of the mass. No recurrence has been observed. CONCLUSIONS: Xeroderma pigmentosum of infancy is a rare disease, and association with keratoacanthoma is even rarer. This condition should be considered in the differential diagnosis of freckles, Rothmund-Thomson syndrome and porphyria.

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