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1.
Neural Regen Res ; 20(1): 277-290, 2025 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38767492

RESUMO

JOURNAL/nrgr/04.03/01300535-202501000-00035/figure1/v/2024-05-14T021156Z/r/image-tiff Our previous study found that rat bone marrow-derived neural crest cells (acting as Schwann cell progenitors) have the potential to promote long-distance nerve repair. Cell-based therapy can enhance peripheral nerve repair and regeneration through paracrine bioactive factors and intercellular communication. Nevertheless, the complex contributions of various types of soluble cytokines and extracellular vesicle cargos to the secretome remain unclear. To investigate the role of the secretome and extracellular vesicles in repairing damaged peripheral nerves, we collected conditioned culture medium from hypoxia-pretreated neural crest cells, and found that it significantly promoted the repair of sensory neurons damaged by oxygen-glucose deprivation. The mRNA expression of trophic factors was highly expressed in hypoxia-pretreated neural crest cells. We performed RNA sequencing and bioinformatics analysis and found that miR-21-5p was enriched in hypoxia-pretreated extracellular vesicles of neural crest cells. Subsequently, to further clarify the role of hypoxia-pretreated neural crest cell extracellular vesicles rich in miR-21-5p in axonal growth and regeneration of sensory neurons, we used a microfluidic axonal dissociation model of sensory neurons in vitro, and found that hypoxia-pretreated neural crest cell extracellular vesicles promoted axonal growth and regeneration of sensory neurons, which was greatly dependent on loaded miR-21-5p. Finally, we constructed a miR-21-5p-loaded neural conduit to repair the sciatic nerve defect in rats and found that the motor and sensory functions of injured rat hind limb, as well as muscle tissue morphology of the hind limbs, were obviously restored. These findings suggest that hypoxia-pretreated neural crest extracellular vesicles are natural nanoparticles rich in miRNA-21-5p. miRNA-21-5p is one of the main contributors to promoting nerve regeneration by the neural crest cell secretome. This helps to explain the mechanism of action of the secretome and extracellular vesicles of neural crest cells in repairing damaged peripheral nerves, and also promotes the application of miR-21-5p in tissue engineering regeneration medicine.

2.
Prep Biochem Biotechnol ; : 1-9, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38847777

RESUMO

Background: Recombinant myofibril-bound serine proteinase (rMBSP) was successfully expressed in Pichia pastoris GS115 in our laboratory. However, low production of rMBSP in shake flask constraints further exploration of properties.Methods: A 5-L high cell density fermentation was performed and the fermentation medium was optimized. Response surface methodology (RSM) was used to optimize the culture condition through modeling three selected parameter.Results: Under the optimized culture medium (LBSM, 1% yeast powder and 1% peptone) and culture conditions (induction pH 5.5, temperature 29 °C, time 40 h), the yield of rMBSP was 420 mg/L in a 5-L fermenter, which was a 6-fold increase over thar, expressed in flask cultivation. The desired enzyme was purified by two-step, which yielded a 33.7% recovery of a product that had over 85% purity. The activity of purified rMBSP was significantly inhibited by Ca2+, Mg2+, SDS, guanidine hydrochloeide, acetone, isopropanol, chloroform, n-hexane and n-heptane. Enzymatic analysis revealed a Km of 2.89 ± 0.09 µM and a Vmax of 14.20 ± 0.12 nM•min-1 for rMBSP. LC-MS/MS analysis demonstrated the specific cleavage of bovine serum albumin by rMPSP.Conclusion: These findings suggest that rMPSP has potential as a valuable enzyme for protein science research.

3.
Arch Virol ; 169(7): 141, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38850364

RESUMO

The brown planthopper (BPH), Nilaparvata lugens, is a significant agricultural pest capable of long-distance migration and transmission of viruses that cause severe disease in rice. In this study, we identified a novel segmented RNA virus in a BPH, and this virus exhibited a close relationship to members of a recently discovered virus lineage known as "quenyaviruses" within the viral kingdom Orthornavirae. This newly identified virus was named "Nilaparvata lugens quenyavirus 1" (NLQV1). NLQV1 consists of five positive-sense, single-stranded RNAs, with each segment containing a single open reading frame (ORF). The genomic characteristics and phylogenetic analysis support the classification of NLQV1 as a novel quenyavirus. Notably, all of the genome segments of NLRV contained the 5'-terminal sequence AUCUG. The characteristic virus-derived small interfering RNA (vsiRNA) profile of NLQV1 suggests that the antiviral RNAi pathway of the host BPH was activated in response to virus infection. These findings represent the first documented report of quenyaviruses in planthoppers, contributing to our understanding of quenyaviruses and expanding our knowledge of insect-specific viruses in planthoppers.


Assuntos
Genoma Viral , Hemípteros , Fases de Leitura Aberta , Filogenia , Vírus de RNA , RNA Viral , Animais , Hemípteros/virologia , Genoma Viral/genética , RNA Viral/genética , Vírus de RNA/genética , Vírus de RNA/classificação , Vírus de RNA/isolamento & purificação , Doenças das Plantas/virologia , Oryza/virologia , Sequenciamento Completo do Genoma , RNA Interferente Pequeno/genética
4.
Sci Rep ; 14(1): 12864, 2024 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-38834664

RESUMO

Natural polymer-based hydrogels have demonstrated great potential as wound-healing dressings. They help to maintain a moist wound environment as well as promote faster healing. In this work, a multifunctional hydrogel was prepared using keratin, sodium alginate, and carboxymethyl chitosan with tannic acid modification. Micro-morphology of hydrogels has been performed by scanning electron microscopy. Fourier Transform Infrared Spectroscopy reveals the presence of hydrogen bonding. The mechanical properties of the hydrogels were examined using a universal testing machine. Furthermore, we investigated several properties of the modified hydrogel. These properties include swelling rate, water retention, anti-freezing properties, antimicrobial and antioxidant properties, hemocompatibility evaluation and cell viability test in vitro. The modified hydrogel has a three-dimensional microporous structure, the swelling rate was 1541.7%, the elastic modulus was 589.74 kPa, the toughness was 211.74 kJ/m3, and the elongation at break was 75.39%, which was similar to the human skin modulus. The modified hydrogel also showed inhibition of S. aureus and E. coli, as well as a DPPH scavenging rate of 95%. In addition, the modified hydrogels have good biological characteristics. Based on these findings, the K/SA/CCS hydrogel holds promise for applications in biomedical engineering.


Assuntos
Alginatos , Quitosana , Hidrogéis , Queratinas , Taninos , Quitosana/química , Quitosana/análogos & derivados , Taninos/química , Alginatos/química , Hidrogéis/química , Humanos , Queratinas/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Antioxidantes/química , Antioxidantes/farmacologia , Escherichia coli/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier , Módulo de Elasticidade , Antibacterianos/química , Antibacterianos/farmacologia
5.
Food Chem ; 455: 139846, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38833863

RESUMO

Eurotium cristatum, a unique probiotic in Fu brick tea, is widely used in food processing to enhance added values. Here, green kernel black beans (GKBBs) were solid-fermented with E. cristatum and dynamic changes in flavour, chemical composition and metabolites during fermentation were investigated. As results, E. cristatum fermentation altered aroma profiles and sensory attributes of GKBBs, especially reduced sourness. After fermentation, total polyphenolic and flavonoid contents in GKBBs were elevated, while polysaccharides, soluble proteins and short-chain fatty acids contents were decreased. E. cristatum fermentation also induced biotransformation of glycosidic isoflavones into sapogenic isoflavones. During fermentation, dynamic changes in levels of 17 amino acids were observed, in which 3 branched-chain amino acids were increased. Non-targeted metabolomics identified 51 differential compounds and 10 related metabolic pathways involved in E. cristatum fermentation of GKBBs. This study lays foundation for the development of green kernel black bean-based functional food products with E. cristatum fermentation.

6.
Zygote ; : 1-6, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38828560

RESUMO

Spermatogenesis is a highly complex process through which mature sperms are produced, and it requires three important stages; mitosis, meiosis and sperm formation. The expression of genes regulated by transcription factors at specific stages exerts important regulatory effects on the development process of germ cells. Male mice with overexpressed programmed death ligand 1 (PD-L1) (B7 homolog1) in the testis have infertility and abnormal sperm development, thereby exhibiting severe malformation and sloughing throughout spermatid maturation and collapsed and disorganized seminiferous epithelium structure. Furthermore, PD-L1 overexpression causes overexpression of cysteine-rich secretory protein 1 (CRISP1) in the epididymis and adversely affects or precludes sperm energization, sperm-pellucida binding and sperm-oocyte fusion. These findings suggest that CRISP1 and PD-L1 can interact with each other to induce male infertility and germ-cell dissociation.

7.
J Genet Genomics ; 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38825039

RESUMO

Mitochondrial dysfunction is a critical factor leading to a wide range of clinically heterogeneous and often severe disorders due to its central role in generating cellular energy. Mutations in the TUFM gene are known to cause combined oxidative phosphorylation deficiency 4 (COXPD4), a rare mitochondrial disorder characterized by a comprehensive quantitative deficiency in mitochondrial respiratory chain (MRC) complexes. The development of a reliable animal model for COXPD4 is crucial for elucidating the roles and mechanisms of TUFM in disease pathogenesis and benefiting its medical management. In this study, we construct a zebrafish tufm-/- mutant that closely resembles the COXPD4 syndrome, exhibiting compromised mitochondrial protein translation, dysfunctional mitochondria with oxidative phosphorylation (OXPHOS) defects, and significant metabolic suppression of the tricarboxylic acid (TCA) cycle. Leveraging this COXPD4 zebrafish model, we comprehensively validate the clinical relevance of TUFM mutations and identify probucol as a promising therapeutic approach for managing COXPD4. Our data offer valuable insights for understanding mitochondrial diseases and developing effective treatments.

8.
J Magn Reson Imaging ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38855837

RESUMO

BACKGROUND: The impact of functional mitral regurgitation and type 2 mellitus diabetes (T2DM) on left ventricular (LV) strain in nonischemic dilated cardiomyopathy (NIDCM) patients remains unclear. PURPOSE: To evaluate the impact of mitral regurgitation severity on LV strain, and explore additive effect of T2DM on LV function across varying mitral regurgitation severity levels in NIDCM patients. STUDY TYPE: Retrospective. POPULATION: 352 NIDCM (T2DM-) patients (49.1 ± 14.6 years, 67% male) (207, 85, and 60 no/mild, moderate, and severe mitral regurgitation) and 96 NIDCM (T2DM+) patients (55.2 ± 12.4 years, 77% male) (47, 30, and 19 no/mild, moderate, and severe mitral regurgitation). FIELD STRENGTH/SEQUENCE: 3.0 T/balanced steady-state free precession sequence. ASSESSMENT: LV geometric parameters and strain were measured and compared among groups. Determinants of LV strain were investigated. STATISTICAL TEST: Student's t-test, Mann-Whitney U test, one-way ANOVA, Kruskal-Wallis test, univariable and multivariable linear regression. P < 0.05 was considered statistically significant. RESULTS: LV GLPS and longitudinal PDSR decreased gradually with increasing mitral regurgitation severity in NIDCM patients with T2DM(GLPS: -5.7% ± 2.1% vs. -4.3% ± 1.6% vs. -2.6% ± 1.3%; longitudinal PDSR:0.5 ± 0.2 sec-1 vs. 0.4 ± 0.2 sec-1 vs. 0.3 ± 0.1 sec-1). NIDCM (T2DM+) demonstrated decreased GCPS and GLPS in the no/mild subgroup, reduced LV GCPS, GLPS, and longitudinal PDSR in the moderate subgroup, and reduced GRPS, GCPS, GLPS, and longitudinal PDSR in the severe subgroup compared with NIDCM (T2DM-) patients. Multivariable regression analysis identified that mitral regurgitation severity (ß = -0.13, 0.15, and 0.25 for GRPS, GCPS, and GLPS) and the presence of T2DM (ß = 0.14 and 0.13 for GCPS and GLPS) were independent determinants of LV strains in NIDCM patients. DATA CONCLUSION: Increased mitral regurgitation severity is associated with reduced LV strains in NIDCM patients with T2DM. The presence of T2DM exacerbated the decline of LV function across various mitral regurgitation levels in NIDCM patients, resulting in reduced LV strains. TECHNICAL EFFICACY: Stage 3.

10.
Bioorg Chem ; 149: 107531, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38850779

RESUMO

Nitroreductase (NTR) overexpression often occurs in tumors, highlighting the significance of effective NTR detection. Despite the utilization of various optical methods for this purpose, the absence of an efficient tumor-targeting optical probe for NTR detection remains a challenge. In this research, a novel tumor-targeting probe (Cy-Bio-NO2) is developed to perform dual-modal NTR detection using near-infrared fluorescence and photoacoustic techniques. This probe exhibits exceptional sensitivity and selectivity to NTR. Upon the reaction with NTR, Cy-Bio-NO2 demonstrates a distinct fluorescence "off-on" response at 800 nm, with an impressive detection limit of 12 ng/mL. Furthermore, the probe shows on-off photoacoustic signal with NTR. Cy-Bio-NO2 has been successfully employed for dual-modal NTR detection in living cells, specifically targeting biotin receptor-positive cancer cells for imaging purposes. Notably, this probe effectively detects tumor hypoxia through dual-modal imaging in tumor-bearing mice. The strategy of biotin incorporation markedly enhances the probe's tumor-targeting capability, facilitating its engagement in dual-modal imaging at tumor sites. This imaging capacity holds substantial promise as an accurate tool for cancer diagnosis.


Assuntos
Corantes Fluorescentes , Nitrorredutases , Imagem Óptica , Nitrorredutases/metabolismo , Nitrorredutases/análise , Animais , Humanos , Camundongos , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Técnicas Fotoacústicas , Estrutura Molecular , Camundongos Nus , Camundongos Endogâmicos BALB C , Neoplasias/diagnóstico por imagem , Neoplasias Experimentais/diagnóstico por imagem , Neoplasias Experimentais/metabolismo
11.
Int J Biol Macromol ; 273(Pt 2): 132939, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38866266

RESUMO

This paper prepared a new kind of carbon dots-polyvinyl alcohol-carboxymethyl cellulose composite film with antibacterial properties. Carbon dots and citric acid were used as cross-linking agents, and polyvinyl alcohol and carboxymethyl cellulose were used as matrices respectively. The mechanical properties, UV shielding performance, thermal stability, antioxidant capability, and antibacterial activities of the carbon dots-polyvinyl alcohol-carboxymethyl cellulose composite film were researched. The prepared carbon dots-polyvinyl alcohol-carboxymethyl cellulose composite film was applied in the strawberry freshness preservation test. And test results indicated that the carbon dots-polyvinyl alcohol-carboxymethyl cellulose composite film could prevent rotting and extend the shelf life of strawberries. This carbon dots-polyvinyl alcohol-carboxymethyl cellulose composite film could be applied in the food active packaging field.

12.
Open Life Sci ; 19(1): 20220733, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38867922

RESUMO

The aim of this research is to explore the application value of Deep residual network model (DRN) for deep learning-based multi-sequence magnetic resonance imaging (MRI) in the staging diagnosis of cervical cancer (CC). This research included 90 patients diagnosed with CC between August 2019 and May 2021 at the hospital. After undergoing MRI examination, the clinical staging and surgical pathological staging of patients were conducted. The research then evaluated the results of clinical staging and MRI staging to assess their diagnostic accuracy and correlation. In the staging diagnosis of CC, the feature enhancement layer was added to the DRN model, and the MRI imaging features of CC were used to enhance the image information. The precision, specificity, and sensitivity of the constructed model were analyzed, and then the accuracy of clinical diagnosis staging and MRI staging were compared. As the model constructed DRN in this research was compared with convolutional neural network (CNN) and the classic deep neural network visual geometry group (VGG), the precision was 67.7, 84.9, and 93.6%, respectively. The sensitivity was 70.4, 82.5, and 91.2%, while the specificity was 68.5, 83.8, and 92.2%, respectively. The precision, sensitivity, and specificity of the model were remarkably higher than those of CNN and VGG models (P < 0.05). As the clinical staging and MRI staging of CC were compared, the diagnostic accuracy of MRI was 100%, while that of clinical diagnosis was 83.7%, showing a significant difference between them (P < 0.05). Multi-sequence MRI under intelligent algorithm had a high diagnostic rate for CC staging, deserving a good clinical application value.

13.
Org Lett ; 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38875468

RESUMO

An unprecedented VCP-CP (vinylcyclopropane-cyclopentene) rearrangement approach has been established herein by virtue of the pyridine-boronyl radical catalyzed intramolecular ring expansions. This metal-free radical pathway harnesses readily available catalysts and unactivated vinylcyclopropane starting materials, providing an array of cyclopentene derivatives chemoselectively under relatively mild conditions. Mechanistic studies support the idea that the boronyl radical engages in the generation of allylic/ketyl radical species, thus inducing the ring opening of cyclopropanes and the following intramolecular cyclization processes.

14.
Sci Total Environ ; : 173938, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38880146

RESUMO

Polycyclic Aromatic Hydrocarbons (PAHs) represent pervasive pollutants, posing health risks in urban environments. It is essential to comprehend the spatiotemporal distributions, composition profiles, and inter-media transfer processes of PAHs in various environmental compartments, influenced by both natural changes and anthropogenic activities. This study integrates historical and future spatiotemporally changing environmental parameters, including climate data, GDP, population data, land-use types, and hydrological variables, into the Multimedia Urban Model (MUM). This integration enables the simulation of spatiotemporal distributions and inter-media transfer fluxes of PAHs among six different media from the 2010s to the 2100s under two distinct Shared Socio-economic Pathways (SSP) scenarios in the megacity of Shanghai, China. The MUM model, featuring diverse gridded parameters, effectively captures PAH concentrations and movement across environmental compartments. Results indicate a decreasing trend in PAHs concentrations in the 2100s compared to the 2010s, with PAH concentrations in water, sediment, vegetation, and organic film covering impermeable surfaces under the SSP3-7.0 scenario higher than those of the SSP1-2.6 scenario. Low molecular weight PAHs dominate in the sediment, water, and air, whereas high molecular weight PAHs prevail in the organic film, vegetation, and soil. Sediment and soil serve as the predominant sinks for PAHs. The primary transport processes for PAH movement include air-film, air-soil, film-water, soil-air, and water-air. Almost all transfer fluxes exhibit a declining trend in future periods except for the air-film transport pathway. The principal input and removal routes for PAHs in Shanghai involve the advection of air and water. The study provides essential insights into the environmental behavior of PAHs and informs targeted pollution control in Shanghai. Additionally, it serves as a technical reference for similar pollution prediction research.

15.
Int J Biol Macromol ; : 132970, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38876239

RESUMO

Bone defects can interfere with bone healing by disrupting the local environment, resulting in vascular damage and hypoxia. Under these conditions, insufficient oxygen availability is a significant factor that exacerbates disease by blocking angiogenesis or osteogenesis. Exosomes play a crucial role in intercellular communication and modulation of inflammation to aid bone regeneration. However, the distance between exosomes and areas of damage can hinder efficient bone generation and cell survival. To overcome this limitation, we fabricated a continuous oxygen-supplying composite scaffold, with the encapsulation of calcium peroxide in a polylactic acid three-dimensional (3D) printing construct (CPS), as both an oxygen source and hydroxyapatite (HAP) precursor. Furthermore, bone marrow mesenchymal stem cell (BMSC)-derived exosomes were incorporated into hyaluronic acid (HA) hydrogels to stimulate cell growth and modulate inflammation. The release of exosomes into cells leads to an increase in alkaline phosphatase production. In vivo results demonstrated that the composite scaffold regulated the inflammatory microenvironment, relieved tissue hypoxia, and promoted new bone formation. These results indicate that the synergistic effect of exosomes and oxygen promoted the proliferation of BMSCs, alleviated inflammation and exhibited excellent osteogenic properties. In conclusion, this osteogenic functional composite scaffold material offers a highly effective approach for bone repair.

16.
Front Pharmacol ; 15: 1389179, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38855739

RESUMO

Background: Quercetin, a widespread polyphenolic flavonoid, is known for its extensive health benefits and is commonly found in the plant kingdom. The natural occurrence and extraction methods of quercetin are crucial due to its bioactive potential. Purpose: This review aims to comprehensively cover the natural sources of quercetin, its extraction methods, bioavailability, pharmacokinetics, and its role in various cell death pathways and liver fibrosis. Methods: A comprehensive literature search was performed across several electronic databases, including PubMed, Embase, CNKI, Wanfang database, and ClinicalTrials.gov, up to 10 February 2024. The search terms employed were "quercetin", "natural sources of quercetin", "quercetin extraction methods", "bioavailability of quercetin", "pharmacokinetics of quercetin", "cell death pathways", "apoptosis", "autophagy", "pyroptosis", "necroptosis", "ferroptosis", "cuproptosis", "liver fibrosis", and "hepatic stellate cells". These keywords were interconnected using AND/OR as necessary. The search focused on studies that detailed the bioavailability and pharmacokinetics of quercetin, its role in different cell death pathways, and its effects on liver fibrosis. Results: This review details quercetin's involvement in various cell death pathways, including apoptosis, autophagy, pyroptosis, necroptosis, ferroptosis, and cuproptosis, with particular attention to its regulatory influence on apoptosis and autophagy. It dissects the mechanisms through which quercetin affects these pathways across different cell types and dosages. Moreover, the paper delves into quercetin's effects on liver fibrosis, its interactions with hepatic stellate cells, and its modulation of pertinent signaling cascades. Additionally, it articulates from a physical organic chemistry standpoint the uniqueness of quercetin's structure and its potential for specific actions in the liver. Conclusion: The paper provides a detailed analysis of quercetin, suggesting its significant role in modulating cell death mechanisms and mitigating liver fibrosis, underscoring its therapeutic potential.

17.
JMIR Med Inform ; 12: e57678, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38857077

RESUMO

BACKGROUND: Tinnitus diagnosis poses a challenge in otolaryngology owing to an extremely complex pathogenesis, lack of effective objectification methods, and factor-affected diagnosis. There is currently a lack of explainable auxiliary diagnostic tools for tinnitus in clinical practice. OBJECTIVE: This study aims to develop a diagnostic model using an explainable artificial intelligence (AI) method to address the issue of low accuracy in tinnitus diagnosis. METHODS: In this study, a knowledge graph-based tinnitus diagnostic method was developed by combining clinical medical knowledge with electronic medical records. Electronic medical record data from 1267 patients were integrated with traditional Chinese clinical medical knowledge to construct a tinnitus knowledge graph. Subsequently, weights were introduced, which measured patient similarity in the knowledge graph based on mutual information values. Finally, a collaborative neighbor algorithm was proposed, which scored patient similarity to obtain the recommended diagnosis. We conducted 2 group experiments and 1 case derivation to explore the effectiveness of our models and compared the models with state-of-the-art graph algorithms and other explainable machine learning models. RESULTS: The experimental results indicate that the method achieved 99.4% accuracy, 98.5% sensitivity, 99.6% specificity, 98.7% precision, 98.6% F1-score, and 99% area under the receiver operating characteristic curve for the inference of 5 tinnitus subtypes among 253 test patients. Additionally, it demonstrated good interpretability. The topological structure of knowledge graphs provides transparency that can explain the reasons for the similarity between patients. CONCLUSIONS: This method provides doctors with a reliable and explainable diagnostic tool that is expected to improve tinnitus diagnosis accuracy.

18.
Opt Express ; 32(9): 15827-15839, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38859223

RESUMO

To advance the development of a compact and highly integrated fiber Bragg grating (FBG) interrogation system, to the best of our knowledge, this paper is the first to present the design and fabrication of a monolithic integration chip based on silicon-on-insulator (SOI), which is specifically intended for application in fiber grating sensing interrogation systems. By considering the impact of coupling structure dimensions on coupling efficiency as well as the effect of the photodetector (PD) parameters on the optical absorption efficiency of the device, we refine the structure of the monolithic integrated chip for arrayed waveguide grating (AWG) and PD. The test results reveal that the coupling loss between AWG and PD is -2.4 dB. The monolithic integrated interrogation chip achieves an interrogation accuracy of approximately 6.79 pm within a dynamic range of 1.56 nm, accompanied by a wavelength resolution of 1 pm. This exceptional performance highlights the potential of the monolithic integrated chip to enhance the integration of AWG-based fiber grating interrogation systems.

19.
Microbiol Spectr ; : e0000824, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38860788

RESUMO

Redundant carbapenemase-producing (RCP) bacteria, which carry double or multiple carbapenemases, represent a new and concerning phenomenon. The objective of this study is to conduct a comprehensive analysis of the epidemiology and genetic mechanisms of RCP strains to support targeted surveillance and control measures. A retrospective analysis was conducted using surveillance data from 277 articles. Statistical analysis was performed to determine and evaluate species prevalence, proportions of carbapenemases, antibiotic susceptibility profiles, sample information, and patient outcomes. Complete plasmid sequencing data were utilized to investigate potential antimicrobial resistance or virulence advantages that strains may gain from acquiring redundant carbapenemases. RCP bacteria are widely distributed globally, and their prevalence is increasing over time. Several countries, including China, India, Iran, Turkey, and South Korea, have reported more than 100 RCP strains. The most commonly reported RCP species are Klebsiella pneumoniae and Acinetobacter baumannii, which exhibit varying proportions of carbapenemase combinations. Certain species-carbapenemase combinations, such as K. pneumoniae carrying New Delhi metallo-ß-lactamase (NDM) + oxacillinase (OXA) (56.76%) and K. pneumoniae carbapenemase (KPC) + Verona integron-encoded metallo-ß-lactamase (VIM) (50.00%) carbapenemases, are associated with high mortality rates. In patients with RCP strains isolated from the bloodstream and respiratory system, the mortality rates are 58.70% and 69.23%, respectively. Analysis of plasmids from RCP strains suggests that they may acquire additional antibiotic resistance phenotypes and virulence factors. Carbapenem-resistant bacteria carrying redundant carbapenemases pose a significant global health threat. This study provides valuable insights into the epidemiology and genetic mechanisms of these bacteria, supporting the development of effective control and prevention strategies to mitigate their transmission.IMPORTANCEThis study examined the global distribution patterns of 1,780 bacteria with double or multiple carbapenemases from 277 articles and assessed their clinical impact. The presence of multiple carbapenemases increases the chances of co-resistance to other classes of antibiotics and more virulence factors, further complicating the clinical management of infections.

20.
Angew Chem Int Ed Engl ; : e202407090, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38840270

RESUMO

Low *CO coverage on the active sites is a major hurdle in the tandem electrocatalysis, resulting in unsatisfied C2H4 production efficiencies. In this work, we developed a synergetic-tandem strategy to construct a copper-based composite catalyst for the electroreduction of CO2 to C2H4, which was constructed via the template-directed polymerization of ultrathin Cu(II) porphyrin organic framework incorporating atomically isolated Cu(II) porphyrin and Cu(II) bipyridine sites on a carbon nanotube (CNT) scaffold, and then Cu2O nanoparticles were uniformly dispersed on the CNT scaffold. The presence of dual active sites within the Cu(II) porphyrin organic framework create a synergetic effect, leading to an increase in local *CO availability to enhance the C-C coupling step implemented on the adjacent Cu2O nanoparticles for further C2H4 production. Accordingly, the resultant catalyst affords an exceptional CO2-to-C2H4 Faradaic efficiency (FEC2H4) of 71.0% at -1.1 V vs reversible hydrogen electrode (RHE), making it one of the most effective copper-based tandem catalysts reported to date. The superior performance of the catalyst is further confirmed through operando infrared spectroscopy and theoretic calculations.

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