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1.
Brief Bioinform ; 24(4)2023 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-37249547

RESUMO

Pathogen detection from biological and environmental samples is important for global disease control. Despite advances in pathogen detection using deep learning, current algorithms have limitations in processing long genomic sequences. Through the deep cross-fusion of cross, residual and deep neural networks, we developed DCiPatho for accurate pathogen detection based on the integrated frequency features of 3-to-7 k-mers. Compared with the existing state-of-the-art algorithms, DCiPatho can be used to accurately identify distinct pathogenic bacteria infecting humans, animals and plants. We evaluated DCiPatho on both learned and unlearned pathogen species using both genomics and metagenomics datasets. DCiPatho is an effective tool for the genomic-scale identification of pathogens by integrating the frequency of k-mers into deep cross-fusion networks. The source code is publicly available at https://github.com/LorMeBioAI/DCiPatho.


Assuntos
Algoritmos , Software , Humanos , Redes Neurais de Computação , Genoma , Genômica
2.
Chem Rev ; 123(16): 10432-10467, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37450853

RESUMO

Metal-organic frameworks (MOFs) and ionic liquids (ILs) represent promising materials for adsorption separation. ILs incorporated into MOF materials (denoted as IL/MOF composites) have been developed, and IL/MOF composites combine the advantages of MOFs and ILs to achieve enhanced performance in the adsorption-based separation of fluid mixtures. The designed different ILs are introduced into the various MOFs to tailor their functional properties, which affect the optimal adsorptive separation performance. In this Perspective, the rational fabrication of IL/MOF composites is presented, and their functional properties are demonstrated. This paper provides a critical overview of an emergent class of materials termed IL/MOF composites as well as the recent advances in the applications of IL/MOF composites as adsorbents or membranes in fluid separation. Furthermore, the applications of IL/MOF in adsorptive gas separations (CO2 capture from flue gas, natural gas purification, separation of acetylene and ethylene, indoor pollutants removal) and liquid separations (separation of bioactive components, organic-contaminant removal, adsorptive desulfurization, radionuclide removal) are discussed. Finally, the existing challenges of IL/MOF are highlighted, and an appropriate design strategy direction for the effective exploration of new IL/MOF adsorptive materials is proposed.

3.
Chem Rev ; 123(16): 10258-10301, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37555677

RESUMO

Condensable gases are the sum of condensable and volatile steam or organic compounds, including water vapor, which are discharged into the atmosphere in gaseous form at atmospheric pressure and room temperature. Condensable toxic and harmful gases emitted from petrochemical, chemical, packaging and printing, industrial coatings, and mineral mining activities seriously pollute the atmospheric environment and endanger human health. Meanwhile, these gases are necessary chemical raw materials; therefore, developing green and efficient capture technology is significant for efficiently utilizing condensed gas resources. To overcome the problems of pollution and corrosion existing in traditional organic solvent and alkali absorption methods, ionic liquids (ILs), known as "liquid molecular sieves", have received unprecedented attention thanks to their excellent separation and regeneration performance and have gradually become green solvents used by scholars to replace traditional absorbents. This work reviews the research progress of ILs in separating condensate gas. As the basis of chemical engineering, this review first provides a detailed discussion of the origin of predictive molecular thermodynamics and its broad application in theory and industry. Afterward, this review focuses on the latest research results of ILs in the capture of several important typical condensable gases, including water vapor, aromatic VOCs (i.e., BTEX), chlorinated VOC, fluorinated refrigerant gas, low-carbon alcohols, ketones, ethers, ester vapors, etc. Using pure IL, mixed ILs, and IL + organic solvent mixtures as absorbents also briefly expanded the related reports of porous materials loaded with an IL as adsorbents. Finally, future development and research directions in this exciting field are remarked.

4.
Genes Dev ; 31(23-24): 2343-2360, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-29326336

RESUMO

The oncogenic transcription factor TAL1/SCL induces an aberrant transcriptional program in T-cell acute lymphoblastic leukemia (T-ALL) cells. However, the critical factors that are directly activated by TAL1 and contribute to T-ALL pathogenesis are largely unknown. Here, we identified AT-rich interactive domain 5B (ARID5B) as a collaborating oncogenic factor involved in the transcriptional program in T-ALL. ARID5B expression is down-regulated at the double-negative 2-4 stages in normal thymocytes, while it is induced by the TAL1 complex in human T-ALL cells. The enhancer located 135 kb upstream of the ARID5B gene locus is activated under a superenhancer in T-ALL cells but not in normal T cells. Notably, ARID5B-bound regions are associated predominantly with active transcription. ARID5B and TAL1 frequently co-occupy target genes and coordinately control their expression. ARID5B positively regulates the expression of TAL1 and its regulatory partners. ARID5B also activates the expression of the oncogene MYC Importantly, ARID5B is required for the survival and growth of T-ALL cells, and forced expression of ARID5B in immature thymocytes results in thymus retention, differentiation arrest, radioresistance, and tumor formation in zebrafish. Our results indicate that ARID5B reinforces the oncogenic transcriptional program by positively regulating the TAL1-induced regulatory circuit and MYC in T-ALL, thereby contributing to T-cell leukemogenesis.


Assuntos
Carcinogênese/genética , Proteínas de Ligação a DNA/metabolismo , Regulação Neoplásica da Expressão Gênica , Proteína 1 de Leucemia Linfocítica Aguda de Células T/metabolismo , Fatores de Transcrição/metabolismo , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Proteínas de Ligação a DNA/genética , Elementos Facilitadores Genéticos/genética , Perfilação da Expressão Gênica , Genes myc/genética , Células HEK293 , Humanos , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Ligação Proteica , Domínios Proteicos/genética , Timócitos/metabolismo , Timo/crescimento & desenvolvimento , Fatores de Transcrição/genética , Ativação Transcricional/genética , Peixe-Zebra
5.
J Physiol ; 602(2): 317-332, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38152023

RESUMO

It has been documented that increased sympathetic activity contributes to the development of cardiovascular diseases, such as hypertension. We previously reported that ß-arrestin-1, a multifunctional cytoskeletal protein, was downregulated in the rostral ventrolateral medulla (RVLM) of the spontaneously hypertensive rat (SHR), and its overexpression elicited an inhibitory effect on sympathetic activity in hypertension. microRNA (miR)-22-3p has been reported to be associated with the pathological progress of hypertension. The purpose of this study was to determine the role of miR-22-3p in ß-arrestin-1-mediated central cardiovascular regulation in hypertension. It was observed that miR-22-3p was upregulated in the RVLM of SHRs compared with normotensive Wistar-Kyoto (WKY) rats, and it was subsequently confirmed to target the ß-arrestin-1 gene using a dual-luciferase reporter assay. miR-22-3p was downregulated in the RVLM using adeno-associated virus with 'tough decoys', which caused a significant increase of ß-arrestin-1 expression and decrease of noradrenaline and blood pressure (BP) in SHRs. However, upregulation of miR-22-3p using lentivirus in the RVLM of WKY rats significantly increased BP. In in vitro PC12 cells, enhanced oxidative stress activity induced by angiotensin II was counteracted by pretreatment with miR-22-3p inhibitor, and this effect could be abolished by ß-arrestin-1 gene knockdown. Furthermore, microglia exhaustion significantly diminished miR-22-3p expression, and enhanced ß-arrestin-1 expression in the RVLM of SHRs. Activation of BV2 cells in vitro evoked a significant increase of miR-22-3p expression, and this BV2 cell culture medium was also able to facilitate miR-22-3p expression in PC12 cells. Collectively, our findings support a critical role for microglia-derived miR-22-3p in inhibiting ß-arrestin-1 in the RVLM, which is involved in central cardiovascular regulation in hypertension. KEY POINTS: Impairment of ß-arrestin-1 function in the rostral ventrolateral medulla (RVLM) has been reported to be associated with the development of sympathetic overactivity in hypertension. However, little is known about the potential mechanisms of ß-arrestin-1 dysfunction in hypertension. miR-22-3p is implicated in multiple biological processes, but the role of miR-22-3p in central regulation of cardiovascular activity in hypertension remains unknown. We predicted that miR-22-3p could directly bind to the ß-arrestin-1 gene (Arrb1), and this hypothesis was confirmed by using a dual-luciferase reporter assay. Inhibition of ß-arrestin-1 by miR-22-3p was further verified in both in vivo and in vitro experiments. Furthermore, our results suggested miR-22-3p as a risk factor for oxidative stress in the RVLM, thus contributing to sympatho-excitation and hypertension. Our present study provides evidence that microglia-derived miR-22-3p may underlie the pathogenesis and progression of neuronal hypertension by inhibiting ß-arrestin-1 in the RVLM.


Assuntos
Hipertensão , MicroRNAs , Animais , Ratos , beta-Arrestina 1/genética , beta-Arrestina 1/metabolismo , Pressão Sanguínea/fisiologia , Luciferases/metabolismo , Bulbo/fisiologia , MicroRNAs/genética , MicroRNAs/metabolismo , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY
6.
Infect Immun ; 92(5): e0011324, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38624215

RESUMO

Malaria, one of the major infectious diseases in the world, is caused by the Plasmodium parasite. Plasmodium antigens could modulate the inflammatory response by binding to macrophage membrane receptors. As an export protein on the infected erythrocyte membrane, Plasmodium surface-related antigen (SRA) participates in the erythrocyte invasion and regulates the immune response of the host. This study found that the F2 segment of P. yoelii SRA activated downstream MAPK and NF-κB signaling pathways by binding to CD68 on the surface of the macrophage membrane and regulating the inflammatory response. The anti-PySRA-F2 antibody can protect mice against P. yoelii, and the pro-inflammatory responses such as IL-1ß, TNF-α, and IL-6 after infection with P. yoelii are attenuated. These findings will be helpful for understanding the involvement of the pathogenic mechanism of malaria with the exported protein SRA.


Assuntos
Antígenos CD , Antígenos de Protozoários , Macrófagos , Malária , Plasmodium yoelii , Animais , Feminino , Humanos , Camundongos , Antígenos CD/metabolismo , Antígenos CD/imunologia , Antígenos de Diferenciação Mielomonocítica/metabolismo , Antígenos de Diferenciação Mielomonocítica/imunologia , Antígenos de Protozoários/imunologia , Antígenos de Protozoários/metabolismo , Antígenos de Superfície/imunologia , Antígenos de Superfície/metabolismo , Membrana Celular/metabolismo , Membrana Celular/imunologia , Inflamação/imunologia , Inflamação/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/parasitologia , Malária/imunologia , Malária/parasitologia , NF-kappa B/metabolismo , NF-kappa B/imunologia , Plasmodium yoelii/imunologia , Ligação Proteica , Transdução de Sinais
7.
Small ; : e2401360, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38708800

RESUMO

Alloying multiple immiscible elements into a nanoparticle with single-phase solid solution structure (high-entropy-alloy nanoparticles, HEA-NPs) merits great potential. To date, various kinds of synthesis techniques of HEA-NPs are developed; however, a continuous-flow synthesis of freestanding HEA-NPs remains a challenge. Here a micron-droplet-confined strategy by flame spray pyrolysis (FSP) to achieve the continuous-flow synthesis of freestanding HEA-NPs, is proposed. The continuous precursor solution undergoes gas shearing and micro-explosion to form nano droplets which act as the micron-droplet-confined reactors. The ultrafast evolution (<5 ms) from droplets to <10 nm nanoparticles of binary to septenary alloys is achieved through thermodynamic and kinetic control (high temperature and ultrafast colling). Among them, the AuPtPdRuIr HEA-NPs exhibit excellent electrocatalytic performance for alkaline hydrogen evolution reaction with 23 mV overpotential to achieve 10 mA cm-2, which is twofold better than that of the commercial Pt/C. It is anticipated that the continuous-flow synthesis by FSP can introduce a new way for the continuous synthesis of freestanding HEA-NP with a high productivity rate.

8.
Small ; : e2309907, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38712486

RESUMO

The biophysical properties of the extracellular matrix (ECM) play a pivotal role in modulating cancer progression via cell-ECM interactions. However, the biophysical properties specific to gastric cancer (GC) remain largely unexplored. Pertinently, GC ECM shows significantly heterogeneous metamorphoses, such as matrix stiffening and intricate restructuring. By combining collagen I and alginate, this study designs an in vitro biomimetic hydrogel platform to independently modulate matrix stiffness and structure across a physiological stiffness spectrum while preserving consistent collagen concentration and fiber topography. With this platform, this study assesses the impacts of matrix biophysical properties on cell proliferation, migration, invasion, and other pivotal dynamics of AGS. The findings spotlight a compelling interplay between matrix stiffness and structure, influencing both cellular responses and ECM remodeling. Furthermore, this investigation into the integrin/actin-collagen interplay reinforces the central role of integrins in mediating cell-ECM interactions, reciprocally sculpting cell conduct, and ECM adaptation. Collectively, this study reveals a previously unidentified role of ECM biophysical properties in GC malignant potential and provides insight into the bidirectional mechanical cell-ECM interactions, which may facilitate the development of novel therapeutic horizons.

9.
J Org Chem ; 89(4): 2718-2725, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38306613

RESUMO

An anodically oxidizing trifluoromethylation cascade of N-cyanamide alkene bearing two electronically differentiated olefin moieties was reported, in which various N-unsaturated acyl cyanamide alkenes and CF3SO2Na acting as readily available starting materials furnished nonaromatic fused azaheterobicyclic compounds in a highly efficient and sustainable manner. The broad substrate scope, facile scalability, and sustainability enabled this electrochemical process to be an appealing complement for trifluoromethylated cyclic amidines.

10.
BMC Neurol ; 24(1): 59, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38336624

RESUMO

OBJECTIVES: Computed tomographic perfusion (CTP) can play an auxiliary role in the selection of patients with acute ischemic stroke for endovascular treatment. However, data on CTP in non-stroke patients with intracranial arterial stenosis are scarce. We aimed to investigate images in patients with asymptomatic intracranial arterial stenosis to determine the detection accuracy and interpretation time of large/medium-artery stenosis or occlusion when combining computed tomographic angiography (CTA) and CTP images. METHODS: We retrospectively reviewed 39 patients with asymptomatic intracranial arterial stenosis from our hospital database from January 2021 to August 2023 who underwent head CTP, head CTA, and digital subtraction angiography (DSA). Head CTA images were generated from the CTP data, and the diagnostic performance for each artery was assessed. Two readers independently interpreted the CTA images before and after CTP, and the results were analyzed. RESULTS: After adding CTP maps, the accuracy (area under the curve) of diagnosing internal carotid artery (R1: 0.847 vs. 0.907, R2: 0.776 vs. 0.887), middle cerebral artery (R1: 0.934 vs. 0.933, R2: 0.927 vs. 0.981), anterior cerebral artery (R1: 0.625 vs. 0.750, R2: 0.609 vs. 0.750), vertebral artery (R1: 0.743 vs. 0.764, R2: 0.748 vs. 0.846), and posterior cerebral artery (R1: 0.390 vs. 0.575, R2: 0.390 vs. 0.585) occlusions increased for both readers (p < 0.05). Mean interpretation time (R1: 72.4 ± 6.1 s vs. 67.7 ± 6.4 s, R2: 77.7 ± 3.8 s vs. 72.6 ± 4.7 s) decreased when using a combination of both images both readers (p < 0.001). CONCLUSIONS: The addition of CTP images improved the accuracy of interpreting CTA images and reduced the interpretation time in asymptomatic intracranial arterial stenosis. These findings support the use of CTP imaging in patients with asymptomatic intracranial arterial stenosis.


Assuntos
AVC Isquêmico , Humanos , Estudos Retrospectivos , Constrição Patológica/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Angiografia por Tomografia Computadorizada/métodos , Perfusão , Angiografia Cerebral/métodos
11.
Dig Dis ; 42(3): 221-229, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38342087

RESUMO

INTRODUCTION: The objective of our study was to develop a nomogram to predict overall survival (OS) and cancer-specific survival (CSS) in patients with gastric signet ring cell carcinoma (GSRCC). METHODS: A total of 3,408 GSRCC patients between 1975 and 2017 were screened from the Surveillance, Epidemiology, and End Results (SEER) database and randomly divided into training and validation cohorts. Univariate and multivariate Cox analyses were conducted to identify independent prognostic factors for the construction of a nomogram. The performance of the model was then assessed by the concordance index (C-index), calibration plot, and area under the receiver operating characteristic curve (AUC). Then, the novel nomogram was further assessed by 64 GSRCC patients from our hospital as the external cohort. RESULTS: We identified age, tumor lymph node metastasis (TNM) staging system, surgery, and chemotherapy as significant independent elements of prognosis. On this basis, a nomogram was constructed, with a C-index of OS in the training and validation cohorts of 0.763 (95% CI: 0.751-0.774) and 0.766 (95% CI: 0.748-0.784) and a C-index of CSS of 0.765 (95% CI: 0.753-0.777) and 0.773 (95% CI: 0.755-0.791), respectively. The AUCs of the nomogram for predicting 2- and 5-year OS were 0.848 and 0.885, respectively, and those for predicting CSS were 0.854 and 0.899, respectively, demonstrating the excellent predictive value of the constructed nomogram compared to the traditional AJCC staging system. Similar results were also observed in both the internal and external validation sets. CONCLUSION: The nomogram provided an accurate tool to predict OS and CSS in patients with GSRCC, which can assist clinicians in making predictions about individual patient survival.


Assuntos
Carcinoma de Células em Anel de Sinete , Nomogramas , Programa de SEER , Neoplasias Gástricas , Humanos , Carcinoma de Células em Anel de Sinete/mortalidade , Carcinoma de Células em Anel de Sinete/patologia , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Prognóstico , Idoso , Adulto , Estadiamento de Neoplasias , Curva ROC , Modelos de Riscos Proporcionais
12.
Macromol Rapid Commun ; : e2400325, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38900581

RESUMO

To overcome the two main obstacles of large-scale application of superspreading material, self assembly is used to prepare superspreading polymer membrane (SPPM) in this work. An amphiphilic SPPM is prepared by capillary force-driven self assembly using PP melt-blown nonwovens and polyvinyl alcohol (PVA). The prepared SPPM has low preparation cost and stable performance since self assembly needs low energy consumption, and the production is thermodynamically stable. By using cryo-electron microscopy, transmission electron microscopy, X-ray photoelectron spectrum and scanning electron microscope with energy dispersive X-ray spectroscopy. It is proved that PVA is successfully assembled on the fiber surface of PP melt-blown nonwovens. The prepared SPPM has excellent spreading performance, the "spreading times" of both water and oil are less than 0.5 s. They showed much superior performance compared to traditional materials when applied in oil-water separation, seawater desalination, and ion separation. This work will definitely promote the development of self assembly, superspreading materials, and related sciences.

13.
Phys Chem Chem Phys ; 26(8): 6991-7000, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38344948

RESUMO

The synthesis of ammonia via an electrochemical nitrogen reduction reaction (NRR, N2 + 6H+ + 6e- → 2NH3), which can weaken but not directly break an inert NN bond under mild conditions via multiple progressive protonation steps, has been proposed as one of the most attractive alternatives for the production of NH3. However, the development of appropriate catalyst materials is a major challenge in the application of NRRs. Recently, single- or multi-metal atoms anchored on two-dimensional (2D) substrates have been demonstrated as ideal candidates for facilitating NRRs. In this work, by applying spin-polarized density functional theory and ab initio molecular dynamic simulations, we systematically explored the performances of nine types of transition metal multi-atoms anchored on a recently developed 2D biphenylene (BPN) sheet in nitrogen reduction. Structural stability and NRR performance catalyzed by TMn (TM = V, Fe, Ni, Mo, Ru, Rh, W, Re, Ir; n = 1-4) clusters anchored on BPN sheets were systematically explored. After a strict six-step screening strategy, it was found that W2, Ru2 and Mo4 clusters loaded on BPN demonstrate superior potential for nitrogen reduction with extremely low onset potentials of -0.26, -0.36 and -0.17 V, respectively. Electronic structure analysis revealed that the enhanced ability of these multi-atom catalysts to effectively capture and reduce the N2 molecule can be attributed to bidirectional charge transfer between the d orbitals of transition metal atoms and molecular orbitals of the adsorbed N2 through a "donation-back donation" mechanism. Our findings highlight the value of BPN sheets as a substrate for designing multi-atom nitrogen reduction reaction catalysts.

14.
Acta Pharmacol Sin ; 45(1): 193-208, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37749237

RESUMO

Metastasis of colorectal cancer (CRC) is a leading cause of mortality among CRC patients. Elevated COX-2 and PD-L1 expression in colon cancer tissue has been linked to distant metastasis of tumor cells. Although COX-2 inhibitors and immune checkpoint inhibitors demonstrate improved anti-tumor efficacy, their toxicity and variable therapeutic effects in individual patients raise concerns. To address this challenge, it is vital to identify traditional Chinese medicine components that modulate COX-2 and PD-1/PD-L1: rosmarinic acid (RA) exerts striking inhibitory effect on COX-2, while ginsenoside Rg1 (GR) possesses the potential to suppress the binding of PD-1/PD-L1. In this study we investigated whether the combination of RA and GR could exert anti-metastatic effects against CRC. MC38 tumor xenograft mouse model with lung metastasis was established. The mice were administered RA (100 mg·kg-1·d-1, i.g.) alone or in combination with GR (100 mg·kg-1·d-1, i.p.). We showed that RA (50, 100, 150 µM) or a COX-2 inhibitor Celecoxib (1, 3, 9 µM) concentration-dependently inhibited the migration and invasion of MC38 cells in vitro. We further demonstrated that RA and Celecoxib inhibited the metastasis of MC38 tumors in vitro and in vivo via interfering with the COX-2-MYO10 signaling axis and inhibiting the generation of filopodia. In the MC38 tumor xenograft mice, RA administration significantly decreased the number of metastatic foci in the lungs detected by Micro CT scanning; RA in combination with GR that had inhibitory effect on the binding of PD-1 and PD-L1 further suppressed the lung metastasis of colon cancer. Compared to COX-2 inhibitors and immune checkpoint inhibitors, RA and GR displayed better safety profiles without disrupting the tissue structures of the liver, stomach and colon, offering insights into the lower toxic effects of clinical traditional Chinese medicine against tumors while retaining its efficacy.


Assuntos
Neoplasias do Colo , Neoplasias Pulmonares , Humanos , Animais , Camundongos , Antígeno B7-H1/metabolismo , Ciclo-Oxigenase 2/metabolismo , Ácido Rosmarínico , Celecoxib/farmacologia , Celecoxib/uso terapêutico , Inibidores de Ciclo-Oxigenase 2/farmacologia , Inibidores de Ciclo-Oxigenase 2/uso terapêutico , Inibidores de Checkpoint Imunológico/uso terapêutico , Receptor de Morte Celular Programada 1/metabolismo , Linhagem Celular Tumoral , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/metabolismo , Neoplasias Pulmonares/tratamento farmacológico
15.
Proc Natl Acad Sci U S A ; 118(37)2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34493676

RESUMO

Body-centered cubic metals including steels and refractory metals suffer from an abrupt ductile-to-brittle transition (DBT) at a critical temperature, hampering their performance and applications. Temperature-dependent dislocation mobility and dislocation nucleation have been proposed as the potential factors responsible for the DBT. However, the origin of this sudden switch from toughness to brittleness still remains a mystery. Here, we discover that the ratio of screw dislocation velocity to edge dislocation velocity is a controlling factor responsible for the DBT. A physical model was conceived to correlate the efficiency of Frank-Read dislocation source with the relative mobility of screw versus edge dislocations. A sufficiently high relative mobility is a prerequisite for the coordinated movement of screw and edge segments to sustain dislocation multiplication. Nanoindentation experiments found that DBT in chromium requires a critical mobility ratio of 0.7, above which the dislocation sources transition from disposable to regeneratable ones. The proposed model is also supported by the experimental results of iron, tungsten, and aluminum.

16.
Eye Contact Lens ; 50(7): 297-304, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38695745

RESUMO

OBJECTIVES: To explore the potential of artificial intelligence (AI) to assist prescription determination for orthokeratology (OK) lenses. METHODS: Artificial intelligence algorithm development followed by a real-world trial. A total of 11,502 OK lenses fitting records collected from seven clinical environments covering major brands. Records were randomly divided in a three-way data split. Cross-validation was used to identify the most accurate algorithm, followed by an evaluation using an independent test data set. An online AI-assisted system was implemented and assessed in a real-world trial involving four junior and three senior clinicians. RESULTS: The primary outcome measure was the algorithm's accuracy (ACC). The ACC of the best performance of algorithms to predict the targeted reduction amplitude, lens diameter, and alignment curve of the prescription was 0.80, 0.82, and 0.83, respectively. With the assistance of the AI system, the number of trials required to determine the final prescription significantly decreased for six of the seven participating clinicians (all P <0.01). This reduction was more significant among junior clinicians compared with consultants (0.76±0.60 vs. 0.32±0.60, P <0.001). Junior clinicians achieved clinical outcomes comparable to their seniors, as 93.96% (140/149) and 94.44% (119/126), respectively, of the eyes fitted achieved unaided visual acuity no worse than 0.8 ( P =0.864). CONCLUSIONS: AI can improve prescription efficiency and reduce discrepancies in clinical outcomes among clinicians with differing levels of experience. Embedment of AI in practice should ultimately help lessen the medical burden and improve service quality for myopia boom emerging worldwide.


Assuntos
Algoritmos , Inteligência Artificial , Miopia , Procedimentos Ortoceratológicos , Prescrições , Humanos , Procedimentos Ortoceratológicos/métodos , Miopia/terapia , Miopia/fisiopatologia , Feminino , Masculino , Lentes de Contato , Criança , Ajuste de Prótese/métodos , Adolescente , Acuidade Visual/fisiologia
17.
Zhongguo Zhong Yao Za Zhi ; 49(1): 279-284, 2024 Jan.
Artigo em Zh | MEDLINE | ID: mdl-38403360

RESUMO

This study systematically combed the existing evidence of Houyanqing Oral Liquid in the treatment of acute pharyngitis from the "6+1" dimensions of safety, effectiveness, economy, innovation, suitability, accessibility, and characteristics of traditional Chinese medicine(TCM) and carried out qualitative and quantitative analysis of the data from each dimension. The multi-criteria decision analysis(MCDA) model and CSC v2.0 were used to evaluate the clinical value of this drug, so as to provide evidence for the selection of essential drugs in the department of otolaryngology and for medical and health decision-making. The dimensions are graded A, B, C, or D. The adverse reactions of Houyanqing Oral Liquid in the treatment of acute pharyngitis were mainly manifested as abdominal pain, diarrhea, rash, etc., which were relieved after drug withdrawal. In terms of safety, it was considered that Houyanqing Oral Liquid had controllable risk and high safety, which was rated as grade B. Compared with ribavirin aerosol alone, Houyanqing Oral Liquid combined with ribavirin aerosol can significantly improve the total response rate, shorten the time to abatement of fever and di-sappearance of throat pain and mucosal congestion, and alleviate mucosal congestion and cough with sputum. With medium-quality evidence, the effectiveness was rated as grade B. Compared with ribavirin aerosol alone, Houyanqing Oral Liquid combined with ribavirin aerosol had cost-effectiveness advantages in the treatment of acute pharyngitis, and its economy was rated as grade C with the evidence of general quality. For acute pharyngitis, Houyanqing Oral Liquid can shorten the disease course and obviously relieve sore throat. Moreover, it can be used for the treatment of radioactive pharyngitis and oral ulcer, and thus its innovation was rated as grade B. With convenient and simple administration and standard and complete drug information, the suitability of this drug was rated as grade B. Houyanqing Oral Liquid is derived from the folk prescription in Hunan province and has been subjected to real-world studies, and thus the TCM characteristics was rated as grade B. According to the ratings of all the dimensions, the comprehensive value of Houyanqing Oral Liquid in the clinical treatment of acute pharyngitis was determined as grade B, with sufficient evidence and clear results. It is suggested that the results should be conditionally converted into relevant policy of clinical basic drug management according to procedures.


Assuntos
Faringite , Ribavirina , Humanos , Ribavirina/uso terapêutico , Doença Aguda , Aerossóis e Gotículas Respiratórios , Faringite/tratamento farmacológico
18.
Kidney Int ; 104(4): 740-753, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37423509

RESUMO

This study tested if matrix metalloproteinase (MMP)-9 promoted microvascular pathology that initiates hypertensive (HT) kidney disease in salt-sensitive (SS) Dahl rats. SS rats lacking Mmp9 (Mmp9-/-) and littermate control SS rats were studied after one week on a normotensive 0.3% sodium chloride (Pre-HT SS and Pre-HT Mmp9-/-) or a hypertension-inducing diet containing 4.0% sodium chloride (HT SS and HT Mmp9-/-). Telemetry-monitored blood pressure of both the HT SS and HT Mmp9-/- rats increased and did not differ. Kidney microvessel transforming growth factor-beta 1 (Tgfb1) mRNA did not differ between Pre-HT SS and Pre-HT Mmp9-/- rats, but with hypertension and expression of Mmp9 and Tgfb1 increased in HT SS rats, along with phospho-Smad2 labeling of nuclei of vascular smooth muscle cells, and with peri-arteriolar fibronectin deposition. Loss of MMP-9 prevented hypertension-induced phenotypic transformation of microvascular smooth muscle cells and the expected increased microvascular expression of pro-inflammatory molecules. Loss of MMP-9 in vascular smooth muscle cells in vitro prevented cyclic strain-induced production of active TGF-ß1 and phospho-Smad2/3 stimulation. Afferent arteriolar autoregulation was impaired in HT SS rats but not in HT Mmp9-/- rats or the HT SS rats treated with doxycycline, an MMP inhibitor. HT SS but not HT Mmp9-/- rats showed decreased glomerular Wilms Tumor 1 protein-positive cells (a marker of podocytes) along with increased urinary podocin and nephrin mRNA excretion, all indicative of glomerular damage. Thus, our findings support an active role for MMP-9 in a hypertension-induced kidney microvascular remodeling process that promotes glomerular epithelial cell injury in SS rats.


Assuntos
Hipertensão Renal , Hipertensão , Ratos , Animais , Metaloproteinase 9 da Matriz/genética , Cloreto de Sódio , Ratos Endogâmicos Dahl , Rim , Hipertensão/complicações , Hipertensão/genética , Pressão Sanguínea , RNA Mensageiro , Cloreto de Sódio na Dieta
19.
Anal Chem ; 95(33): 12459-12469, 2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37566460

RESUMO

To sensitively monitor trace amounts of alternariol (AOH) in fruits, a dual-mode aptamer sensor utilizing the dual-function nanomaterial PoPD/Ru-Au was developed. This sensor provides both electrochemical (EC) and electrochemiluminescence (ECL) signals, which can greatly avoid the potential false positive of the traditional single signal, thus enhancing the accuracy and reliability of detection results. Polyo-phenylenediamine (PoPD), known for its favorable EC response, can also assist in enhancing the ECL behavior of Ru-Au. Furthermore, Ru-Au demonstrates excellent ECL performance and effectively activates K2S2O8 to amplify the EC response of PoPD. The complementary effect of the two can effectively amplify the final detection signal. Additionally, the PoPD/Ru-Au nanomaterial exhibits excellent electrical conductivity, further enhancing the EC and ECL response signals. The experimental results demonstrate that the EC detection range of AOH was 0.01-100 ng/mL, while the ECL detection range was 0.001-100 ng/mL, both exhibiting a satisfactory linear relationship. Therefore, the mutual verification of the detection results can be highly realized, and the purpose of avoiding wrong detection can be achieved.

20.
Small ; 19(52): e2300319, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37649223

RESUMO

Controlling the heterogeneous nucleation of new phases is of importance in tuning the microstructures and properties of materials. However, the role of vacancy-a popular defect in materials that is hard to be resolved under conventional electron microscopy-in the heterogeneous phase nucleation remains intriguing. Here, this work captures direct in situ experimental evidences that vacancy clusters promote the heterogeneous hydride nucleation and cause the anomalous precipitation memory effect in zirconium. Both interstitial and vacancy dislocation loops form after hydride dissolution. Interestingly, hydride reprecipitation only occurs on those vacancy loop decorated sites during cooling. Atomistic simulations reveal that hydrogen atoms are preferentially segregated at individual vacancy and vacancy clusters, which assist hydride nucleation, and stimulate the unusual memory effect during hydride reprecipitation. The finding breaks the traditional view on the sequence of heterogeneous nucleation sites and sheds light on the solid phase transformation related to vacancy-sensitive alloying elements.

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