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1.
IEEE Trans Med Imaging ; PP2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38771692

RESUMEN

Left ventricle (LV) endocardium segmentation in echocardiography video has received much attention as an important step in quantifying LV ejection fraction. Most existing methods are dedicated to exploiting temporal information on top of 2D convolutional networks. In addition to single appearance semantic learning, some research attempted to introduce motion cues through the optical flow estimation (OFE) task to enhance temporal consistency modeling. However, OFE in these methods is tightly coupled to LV endocardium segmentation, resulting in noisy inter-frame flow prediction, and post-optimization based on these flows accumulates errors. To address these drawbacks, we propose dynamic-guided spatiotemporal attention (DSA) for semi-supervised echocardiography video segmentation. We first fine-tune the off-the-shelf OFE network RAFT on echocardiography data to provide dynamic information. Taking inter-frame flows as additional input, we use a dual-encoder structure to extract motion and appearance features separately. Based on the connection between dynamic continuity and semantic consistency, we propose a bilateral feature calibration module to enhance both features. For temporal consistency modeling, the DSA is proposed to aggregate neighboring frame context using deformable attention that is realized by offsets grid attention. Dynamic information is introduced into DSA through a bilateral offset estimation module to effectively combine with appearance semantics and predict attention offsets, thereby guiding semantic-based spatiotemporal attention. We evaluated our method on two popular echocardiography datasets, CAMUS and EchoNet-Dynamic, and achieved state-of-the-art.

2.
Microbiol Spectr ; : e0052924, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38771033

RESUMEN

The objective of this study was to characterize a novel circulating recombinant form of human immunodeficiency virus type 1 (HIV-1) among people living with HIV in Karachi, Pakistan. We conducted near-full-length genome (NFLG) sequencing on eight samples exhibiting D/G recombination signals in the pol gene region. We successfully obtained NFLG sequences (790-9,614; with reference to the HXB2 genome) from four of the eight samples and then conducted phylogenetic and recombination analyses on them. The four NFLG sequences from our study and one DG unique recombinant form previously identified in the United Kingdom (GenBank accession: MF109700) formed a distinct monophyletic cluster with an Shimodaira-Hasegawa approximate likelihood ratio test node support value of 100%. Bootscan analyses of the five NFLG sequences of DG recombinants showed that all five NFLGs shared the same unique mosaic pattern of recombination breakpoints between D and G clades, with two D fragments in the pol and vif regions inserted into a G backbone. Subregion phylogenetic analyses confirmed these sequences to be a novel circulating recombinant form (CRF) composed of subtypes D and G. The DG recombinant sequences were eventually designated as CRF152_DG by the Los Alamos HIV Sequence Database staff. IMPORTANCE: In Pakistan, the genetic diversity of human immunodeficiency virus type 1 (HIV-1) is becoming increasingly complex, compared to the early years of the epidemic that started after the detection of the first cases of HIV-1 in 1987 in Karachi. Based on the available molecular studies, two dominant HIV-1 clades, sub-subtype A1 and CRF02_AG, have been found to co-circulate with other clades, namely B, C, D, G, CRF01_AE, CRF35_A1D, and CRF56_cpx, in various urban areas of Pakistan. Several novel recombinant forms have also been detected. This first report of CRF152_DG highlights the complex nature of the HIV epidemic in Pakistan and emphasizes the importance of continual molecular surveillance (ideally based on whole-genome sequences) of HIV.

3.
J Endocrinol ; 262(1)2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38692289

RESUMEN

CD44, a cell surface adhesion receptor and stem cell biomarker, is recently implicated in chronic metabolic diseases. Ablation of CD44 ameliorates adipose tissue inflammation and insulin resistance in obesity. Here, we investigated cell type-specific CD44 expression in human and mouse adipose tissue and further studied how CD44 in preadipocytes regulates adipocyte function. Using Crispr Cas9-mdediated gene deletion and lentivirus-mediated gene re-expression, we discovered that deletion of CD44 promotes adipocyte differentiation and adipogenesis, whereas re-expression of CD44 abolishes this effect and decreases insulin responsiveness and adiponectin secretion in 3T3-L1 cells. Mechanistically, CD44 does so via suppressing Pparg expression. Using quantitative proteomics analysis, we further discovered that cell cycle-regulated pathways were mostly decreased by deletion of CD44. Indeed, re-expression of CD44 moderately restored expression of proteins involved in all phases of the cell cycle. These data were further supported by increased preadipocyte proliferation rates in CD44-deficient cells and re-expression of CD44 diminished this effect. Our data suggest that CD44 plays a crucial role in regulating adipogenesis and adipocyte function possibly through regulating PPARγ and cell cycle-related pathways. This study provides evidence for the first time that CD44 expressed in preadipocytes plays key roles in regulating adipocyte function outside immune cells where CD44 is primarily expressed. Therefore, targeting CD44 in (pre)adipocytes may provide therapeutic potential to treat obesity-associated metabolic complications.


Asunto(s)
Células 3T3-L1 , Adipocitos , Adipogénesis , Ciclo Celular , Receptores de Hialuranos , PPAR gamma , Adipogénesis/genética , Adipogénesis/fisiología , Receptores de Hialuranos/metabolismo , Receptores de Hialuranos/genética , Animales , PPAR gamma/metabolismo , PPAR gamma/genética , Ratones , Ciclo Celular/genética , Ciclo Celular/fisiología , Humanos , Adipocitos/metabolismo , Eliminación de Gen , Diferenciación Celular/genética , Masculino , Tejido Adiposo/metabolismo , Tejido Adiposo/citología , Transducción de Señal/fisiología
4.
J Ethnopharmacol ; : 118318, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38754642

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: The Niaodukang mixture (NDK) is a preparation known for its ability to lower serum creatine levels in individuals with chronic kidney disease (CKD) and is commonly administered at medical facilities like the Zhongshan Hospital of Traditional Chinese Medicine. The initial use of NDK was mainly to treat CKD. Our hospital frequently utilizes NDK, which consists of Rheum officinaleBaill., Salvia miltiorrhiza Bunge., Astragalus aaronii(Eig) Zohary., Carthamus tinctorius L., and Sanguisorba officinalis L., for treating patients with CKD-MBD. It has the effects of eliminating dampness and turbidity and dredging kidney collaterals. However, The impact and process of NDK in chronic kidney disease remain unknown. AIM OF THE STUDY: To determine whether microRNA-146a (miR-146a) is associated with CKD micro-inflammationand whether NDK protects against CKD micro-inflammation by modulating the miR-146a/nuclear factor kappa-B (NF-κB) signaling pathway. MATERIALS AND METHODS: (1) An adenine-induced rat model of chronic kidney disease was created through the use of materials and methods. The levels of miR-146a in exosomes from plasma and ileum were determined by RT-PCR. (2) Human cloned colon adenocarcinoma (Caco-2)cellswere stimulated with lipopolysaccharide (LPS)and transfected with miR-146a mimic and inhibitor. Following that, the western blot and RT-PCR techniques were used to measure the protein and mRNA quantities of Toll-like receptor 4 (TLR4), NF-κB, and TNF receptor-associated factor 6 (TRAF6).(3) Enzyme-linked immunosorbent assay (ELISA) was used to identify serum levels of interleukin-1ß (IL-1ß), interleukin-6 (IL-6), and tumor necrosis factor α (TNF-α). (4) Plasma exosomes were extracted, and the exosomes in intestinal tissues were extracted via ultrahigh-speed centrifugation.Negative staining electron microscopy was used to analyze the morphology of exosomes and the ultrastructure of intestinal tissue and exosomes. The particle size of the exosomes was measured using nanoparticle tracking analysis. RESULTS: The pathological characteristics of CKD rats included those associated with systemic micro-inflammation, which may be associated with the release of exosomes in intestinal tissue. NDK suppressed the inflammatory response in Caco-2 cells and decreased the levels of IL-1ß, IL-6, and TNF-α in rats with CKD. The expression of miR-146a, which regulates inflammation, differed between plasma-derived and enterogenous exosomes in CKD rats, which may be due to stimulation of ileal exosome release into the blood. NDK effectively reduced the levels of TRAF6, NF-κB, and TLR4 in the ileum tissue of CKD rats. CONCLUSION: NDK can effectively improve micro-inflammation in CKD ratsby enhancing the release of enterogenous exosomes, thereby enhancing the release of exosome-associated miR-146a and inhibiting micro-inflammation.

5.
Arch Biochem Biophys ; 756: 109997, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38621443

RESUMEN

The preservation of the native conformation and functionality of membrane proteins has posed considerable challenges. While detergents and liposome reconstitution have been traditional approaches, nanodiscs (NDs) offer a promising solution by embedding membrane proteins in phospholipids encircled by an amphipathic helical protein MSP belt. Nevertheless, a drawback of commonly used NDs is their limited homogeneity and stability. In this study, we present a novel approach to construct covalent annular nanodiscs (cNDs) by leveraging microbial transglutaminase (MTGase) to catalyze isopeptide bond formation between the side chains of terminal amino acids, specifically Lysine (K) and Glutamine (Q). This methodology significantly enhances the homogeneity and stability of NDs. Characterization of cNDs and the assembly of membrane proteins within them validate the successful reconstitution of membrane proteins with improved homogeneity and stability. Our findings suggest that cNDs represent a more suitable tool for investigating interactions between membrane proteins and lipids, as well as for analyzing membrane protein structures.


Asunto(s)
Proteínas de la Membrana , Nanoestructuras , Transglutaminasas , Nanoestructuras/química , Proteínas de la Membrana/química , Proteínas de la Membrana/metabolismo , Transglutaminasas/química , Transglutaminasas/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo
6.
Zhongguo Zhong Yao Za Zhi ; 49(5): 1206-1216, 2024 Mar.
Artículo en Chino | MEDLINE | ID: mdl-38621967

RESUMEN

Soil microbiome is a key evaluation index of soil health. Previous studies have shown that organic fertilizer from traditional Chinese medicine(TCM)residues can improve the yield and quality of cultivated traditional Chinese medicinal materials. However, there are few reports on the effects of organic fertilizer from TCM residues on soil microbiome. Therefore, on the basis of evaluating the effects of organic fertilizer from TCM residues on the yield and quality of cultivated Salvia miltiorrhiza, the metagenomic sequencing technique was used to study the effects of organic fertilizer from TCM residues on rhizosphere microbiome community and function of cultivated S. miltiorrhiza. The results showed that:(1) the application of organic fertilizer from TCM residues promoted the growth of S. miltiorrhiza and the accumulation of active components, and the above-ground and underground dry weight and fresh weight of S. miltiorrhiza increased by 371.4%, 288.3%, 313.4%, and 151.9%. The increases of rosmarinic acid and salvianolic acid B were 887.0% and 183.0%.(2)The application of organic fertilizer from TCM residues significantly changed the rhizosphere bacterial and fungal community structures, and the microbial community composition was significantly different.(3)The relative abundance of soil-beneficial bacteria, such as Nitrosospira multiformis, Bacillus subtilis, Lysobacter enzymogenes, and Trichoderma was significantly increased by the application of organic fertilizer from TCM residues.(4)KEGG function prediction analysis showed that metabolism-related microorganisms were more easily enriched in the soil environment after organic fertilizer application. The abundance of functional genes related to nitrification and denitrification could also be increased after the application of organic fertilizer from TCM residues. The results of this study provide guidance for the future application of organic fertilizer from TCM residues in the cultivation of traditio-nal Chinese medicinal materials and enrich the content of green cultivation technology of traditional Chinese medicinal materials.


Asunto(s)
Micobioma , Salvia miltiorrhiza , Suelo/química , Salvia miltiorrhiza/química , Fertilizantes , Medicina Tradicional China , Bacterias/genética , Microbiología del Suelo
7.
Comput Methods Programs Biomed ; 248: 108110, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38452685

RESUMEN

BACKGROUND AND OBJECTIVE: High-resolution (HR) MR images provide rich structural detail to assist physicians in clinical diagnosis and treatment plan. However, it is arduous to acquire HR MRI due to equipment limitations, scanning time or patient comfort. Instead, HR MRI could be obtained through a number of computer assisted post-processing methods that have proven to be effective and reliable. This paper aims to develop a convolutional neural network (CNN) based super-resolution reconstruction framework for low-resolution (LR) T2w images. METHOD: In this paper, we propose a novel multi-modal HR MRI generation framework based on deep learning techniques. Specifically, we construct a CNN based on multi-resolution analysis to learn an end-to-end mapping between LR T2w and HR T2w, where HR T1w is fed into the network to offer detailed a priori information to help generate HR T2w. Furthermore, a low-frequency filtering module is introduced to filter out the interference from HR-T1w during high-frequency information extraction. Based on the idea of multi-resolution analysis, detailed features extracted from HR T1w and LR T2w are fused at two scales in the network and then HR T2w is reconstructed by upsampling and dense connectivity module. RESULTS: Extensive quantitative and qualitative evaluations demonstrate that the proposed method enhances the recovered HR T2w details and outperforms other state-of-the-art methods. In addition, the experimental results also suggest that our network has a lightweight structure and favorable generalization performance. CONCLUSION: The results show that the proposed method is capable of reconstructing HR T2w with higher accuracy. Meanwhile, the super-resolution reconstruction results on other dataset illustrate the excellent generalization ability of the method.


Asunto(s)
Almacenamiento y Recuperación de la Información , Médicos , Humanos , Imagen por Resonancia Magnética , Redes Neurales de la Computación , Procesamiento de Imagen Asistido por Computador
8.
J Enzyme Inhib Med Chem ; 39(1): 2318645, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38465731

RESUMEN

A series of novel benzimidazole derivatives were designed and synthesised based on the structures of reported oral available ALK inhibitor and HDAC inhibitor, pracinostat. In enzymatic assays, compound 3b, containing a 2-acyliminobenzimidazole moiety and hydroxamic acid side chain, could inhibit both ALK and HDAC6 (IC50 = 16 nM and 1.03 µM, respectively). Compound 3b also inhibited various ALK mutants known to be involved in crizotinib resistance, including mutant L1196M (IC50, 4.9 nM). Moreover, 3b inhibited the proliferation of several cancer cell lines, including ALK-addicted H2228 cells. To evaluate its potential for treating cancers in vivo, 3b was used in a human A549 xenograft model with BALB/c nude mice. At 20 mg/kg, 3b inhibited tumour growth by 85% yet had a negligible effect on mean body weight. These results suggest a attracting route for the further research and optimisation of dual ALK/HDAC inhibitors.


Asunto(s)
Antineoplásicos , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Ratones , Animales , Humanos , Quinasa de Linfoma Anaplásico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Inhibidores de Histona Desacetilasas/farmacología , Ratones Desnudos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/metabolismo , Proliferación Celular , Inhibidores de Proteínas Quinasas/química , Antineoplásicos/química , Línea Celular Tumoral
9.
Ann Med ; 56(1): 2316258, 2024 12.
Artículo en Inglés | MEDLINE | ID: mdl-38364214

RESUMEN

INTRODUCTION: Establishing reference ranges for central airway parameters and exploring their influencing factors in Han Chinese non-smoking adults. METHODS: This prospective cross-sectional study was conducted on Han Chinese non-smoking adults who underwent chest CT scans at the Tongzhou Campus of Dongzhimen Hospital Affiliated with the Beijing University of Chinese Medicine between September 2022 and November 2022. The SYNAPSE 3D image analysis software was utilized, enabling the extraction of critical parameters such as central airway length, airway wall thickness (AWT), airway lumen area (ALA), and subcarinal angle (SCA). Pearson's correlation coefficient analysis and multiple linear regression analysis methods were employed to evaluate the relationship between central airway parameters and age, sex, weight, and height. RESULTS: The study encompassed 888 Han Chinese non-smoking adults, comprising 456 females and 432 males. Significant sex differences were noted in central airway length, AWT, and ALA, with measurements in males exceeding those in females (p < 0.01) with no significant difference in SCA. Correlation analyses unveiled relationships between central airway parameters and age, sex, weight, and height. During multiple linear regression analyses, no conclusive evidence emerged to demonstrate the independent or combined explanatory or predictive capacity of the aforementioned variables for central airway length and SCA. Although sex has a significant impact on AWT and ALA, its capability in explanation or prediction remains limited. The conclusions drawn from the primary analysis receive reinforcement from the outcomes of sensitivity analyses. CONCLUSION: Establishing the distribution range of central airway parameters in non-smoking Han Chinese adults. It observed significant sex differences in these parameters, except for the SCA. However, the study found that the predictive or explanatory power of age, sex, weight, and height for central airway parameters was either limited or non-significant.


Asunto(s)
Sistema Respiratorio , Tomografía Computarizada por Rayos X , Adulto , Femenino , Humanos , Masculino , China/epidemiología , Estudios Transversales , Estudios Prospectivos , Pueblos del Este de Asia , Sistema Respiratorio/anatomía & histología
10.
Curr Microbiol ; 81(3): 86, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38305917

RESUMEN

Salmonella is responsible for the majority of food poisoning outbreaks around the world. Pathogenic Salmonella mostly carries a virulence plasmid that contains the Salmonella plasmid virulence gene (spv), a highly conserved sequence encoding effector proteins that can manipulate host cells. Intestinal epithelial cells are crucial components of the innate immune system, acting as the first barrier of defense against infection. When the barrier is breached, Salmonella encounters the underlying macrophages in lamina propria, triggering inflammation and engaging in combat with immune cells recruited by inflammatory factors. Host regulated cell death (RCD) provides a variety of means to fight against or favour Salmonella infection. However, Salmonella releases effector proteins to regulate RCD, evading host immune killing and neutralizing host antimicrobial effects. This review provides an overview of pathogen-host interactions in terms of (1) pathogenicity of Salmonella spv on intestinal epithelial cells and macrophages, (2) mechanisms of host RCD to limit or promote pathogenic Salmonella expansion, and (3) effects and mechanisms of Salmonella spv gene on host RCD.


Asunto(s)
Muerte Celular Regulada , Salmonella , Virulencia/genética , Salmonella/genética , Factores de Virulencia/genética , Factores de Virulencia/metabolismo , Plásmidos/genética
11.
Sci Adv ; 10(5): eadj3808, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38306424

RESUMEN

G protein-coupled receptor 39 (GPR39) senses the change of extracellular divalent zinc ion and signals through multiple G proteins to a broad spectrum of downstream effectors. Here, we found that GPR39 was prevalent at inhibitory synapses of spinal cord somatostatin-positive (SOM+) interneurons, a mechanosensitive subpopulation that is critical for the conveyance of mechanical pain. GPR39 complexed specifically with inhibitory glycine receptors (GlyRs) and helped maintain glycinergic transmission in a manner independent of G protein signalings. Targeted knockdown of GPR39 in SOM+ interneurons reduced the glycinergic inhibition and facilitated the excitatory output from SOM+ interneurons to spinoparabrachial neurons that engaged superspinal neural circuits encoding both the sensory discriminative and affective motivational domains of pain experience. Our data showed that pharmacological activation of GPR39 or augmenting GPR39 interaction with GlyRs at the spinal level effectively alleviated the sensory and affective pain induced by complete Freund's adjuvant and implicated GPR39 as a promising therapeutic target for the treatment of inflammatory mechanical pain.


Asunto(s)
Dolor , Receptores Acoplados a Proteínas G , Humanos , Neuronas/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Glicina/metabolismo , Transducción de Señal , Médula Espinal/metabolismo
12.
Angew Chem Int Ed Engl ; 63(11): e202318142, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38265124

RESUMEN

Precisely introducing topological defects is an important strategy in nanographene crystal engineering because defects can tune π-electronic structures and control molecular assemblies. The synergistic control of the synthesis and assembly of nanographenes by embedding the topological defects to afford two-dimensional (2D) crystals on surfaces is still a great challenge. By in-situ embedding ladder bipyrazinylene (LBPy) into acene, the narrowest nanographene with zigzag edges, we have achieved the precise preparation of 2D nonbenzenoid heteroacene crystals on Au(111). Through intramolecular electrocyclization of o-diisocyanides and Au adatom-directed [2+2] cycloaddition, the nonbenzenoid heteroacene products are produced with high chemoselectivity, and lead to the molecular 2D assembly via LBPy-derived interlocking hydrogen bonds. Using bond-resolved scanning tunneling microscopy, we determined the atomic structures of the nonbenzenoid heteroacene product and diverse organometallic intermediates. The tunneling spectroscopy measurements revealed the electronic structure of the nonbenzenoid heteroacene, which is supported by density functional theory (DFT) calculations. The observed distinct organometallic intermediates during progression annealing combined with DFT calculations demonstrated that LBPy formation proceeds via electrocyclization of o-diisocyanides, trapping of heteroarynes by Au adatoms, and stepwise elimination of Au adatoms.

13.
Molecules ; 29(1)2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-38202827

RESUMEN

Auricularia auricula polysaccharides used in Pinus koraiensis polyphenol encapsulation and delivery under weightlessness are rarely reported. In this study, an anionic polysaccharide fragment named AAP Iα with a molecular weight of 133.304 kDa was isolated and purified to construct a polyphenol encapsulation system. Nanoparticles named NPs-PP loaded with a rough surface for Pinus koraiensis polyphenol (PP) delivery were fabricated by AAP Iα and ε-poly-L-lysine (ε-PL). SEM and the DLS tracking method were used to observe continuous changes in AAP Iα, ε-PL and PP on the nanoparticles' rough surface assembly, as well as the dispersion and stability. Hydrophilic, monodisperse and highly negative charged nanoparticles can be formed at AAP Iα 0.8 mg/mL, ε-PL 20 µg/mL and PP 80 µg/mL. FT-IR was used to determine their electrostatic interactions. Release kinetic studies showed that nanoparticles had an ideal gastrointestinal delivery effect. NPs-PP loaded were assembled through electrostatic interactions between polyelectrolytes after hydrogen bonding formation in PP-AAP Iα and PP-ε-PL, respectively. Colon adhesion properties and PP delivery in vivo of nanoparticles showed that NPs-PP loaded had high adhesion efficiency to the colonic mucosa under simulated microgravity and could enhance PP bioavailability. These results suggest that AAP Iα can be used in PP encapsulation and delivery under microgravity in astronaut food additives.


Asunto(s)
Auricularia , Nanopartículas , Pinus , Ingravidez , Cinética , Espectroscopía Infrarroja por Transformada de Fourier , Lisina
14.
Sensors (Basel) ; 24(1)2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-38203124

RESUMEN

In the field of maneuvering target tracking, the combined observations of azimuth and Doppler may cause weak observation or non-observation in the application of traditional target-tracking algorithms. Additionally, traditional target tracking algorithms require pre-defined multiple mathematical models to accurately capture the complex motion states of targets, while model mismatch and unavoidable measurement noise lead to significant errors in target state prediction. To address those above challenges, in recent years, the target tracking algorithms based on neural networks, such as recurrent neural networks (RNNs), long short-term memory (LSTM) networks, and transformer architectures, have been widely used for their unique advantages to achieve accurate predictions. To better model the nonlinear relationship between the observation time series and the target state time series, as well as the contextual relationship among time series points, we present a deep learning algorithm called recursive downsample-convolve-interact neural network (RDCINN) based on convolutional neural network (CNN) that downsamples time series into subsequences and extracts multi-resolution features to enable the modeling of complex relationships between time series, which overcomes the shortcomings of traditional target tracking algorithms in using observation information inefficiently due to weak observation or non-observation. The experimental results show that our algorithm outperforms other existing algorithms in the scenario of strong maneuvering target tracking with the combined observations of azimuth and Doppler.

15.
Materials (Basel) ; 17(2)2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38255445

RESUMEN

Electromagnetic rail launch technology has attracted increasing attention owing to its advantages in terms of range, firepower, and speed. However, due to electricity-magnetism-heat-force coupling, the surface of the armature-rail friction pair becomes severely damaged, which restricts the development of this technology. A series of studies have been conducted to reduce the damage of the armature-rail friction pair, including an analysis of the damage mechanism and protection strategies. In this study, various types of surface damage were classified into mechanical, electrical, and coupling damages according to their causes. This damage is caused by factors such as mechanical friction, mechanical impact, and electric erosion, either individually or in combination. Then, a detailed investigation of protection strategies for reducing damage is introduced, including material improvement through the use of novel combined deformation and heat treatment processes to achieve high strength and high conductivity, as well as surface treatment technologies such as structural coatings for wear resistance and functional coatings for ablation and melting resistance. Finally, future development prospects of armature-rail friction pair materials are discussed. This study provides a theoretical basis and directions for the development of high-performance materials for the armature-rail friction pair.

16.
Int J Biol Macromol ; 259(Pt 2): 129229, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38211913

RESUMEN

The medicinal Dendrobium species of Orchidaceae possess significant pharmaceutical value, and modern pharmacological research has shown that Dendrobium contains many important active ingredients. Alkaloids, the crucial components of medicinal Dendrobium, demonstrate beneficial healing properties in cardiovascular, cataract, gastrointestinal, and respiratory diseases. Members of the cytochrome P450 monooxygenase (CYP) gene family play essential roles in alkaloid synthesis, participating in alkaloid terpene skeleton construction and subsequent modifications. Although studies of the CYP family have been conducted in some species, genome-wide characterization and systematic analysis of the CYP family in medicinal Dendrobium remain underexplored. In this study, we identified CYP gene family members in the genomes of four medicinal Dendrobium species recorded in the Pharmacopoeia: D. nobile, D. chrysotoxum, D. catenatum, and D. huoshanense. Further, we analyzed the motif composition, gene replication events, and selection pressure of this family. Syntenic analysis revealed that members of the clan 710 were present on chromosome 18 in three medicinal Dendrobium species, except for D. nobile, indicating a loss of clan 710 occurring in D. nobile. We also conducted an initial screening of the CYP genes involved in alkaloid synthesis through transcriptome sequencing. Quantitative real-time reverse transcription PCR showed that the expression of DnoNew43 and DnoNew50, homologs of secologanin synthase involved in the alkaloid synthesis pathway, was significantly higher in the stems than in the leaves. This result coincided with the distribution of dendrobine content in Dendrobium stems and leaves, indicating that these two genes might be involved in the dendrobine synthesis pathway. Our results give insights into the CYP gene family evolution analysis in four medicinal Dendrobium species for the first time and identify two related genes that may be involved in alkaloid synthesis, providing a valuable resource for further investigations into alkaloid synthesis pathway in Dendrobium and other medicinal plants.


Asunto(s)
Alcaloides , Dendrobium , Dendrobium/genética , Alcaloides/genética , Alcaloides/análisis , Vías Biosintéticas/genética , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Terpenos/metabolismo
17.
Cell Death Dis ; 15(1): 76, 2024 01 20.
Artículo en Inglés | MEDLINE | ID: mdl-38245531

RESUMEN

The Hippo pathway's main effector, Yes-associated protein (YAP), plays a crucial role in tumorigenesis as a transcriptional coactivator. YAP's phosphorylation by core upstream components of the Hippo pathway, such as mammalian Ste20 kinase 1/2 (MST1/2), mitogen-activated protein kinase kinase kinase kinases (MAP4Ks), and their substrate, large tumor suppressor 1/2 (LATS1/2), influences YAP's subcellular localization, stability, and transcriptional activity. However, recent research suggests the existence of alternative pathways that phosphorylate YAP, independent of these core upstream Hippo pathway components, raising questions about additional means to inactivate YAP. In this study, we present evidence demonstrating that TSSK1B, a calcium/calmodulin-dependent protein kinase (CAMK) superfamily member, is a negative regulator of YAP, suppressing cellular proliferation and oncogenic transformation. Mechanistically, TSSK1B inhibits YAP through two distinct pathways. Firstly, the LKB1-TSSK1B axis directly phosphorylates YAP at Ser94, inhibiting the YAP-TEAD complex's formation and suppressing its target genes' expression. Secondly, the TSSK1B-LATS1/2 axis inhibits YAP via phosphorylation at Ser127. Our findings reveal the involvement of TSSK1B-mediated molecular mechanisms in the Hippo-YAP pathway, emphasizing the importance of multilevel regulation in critical cellular decision-making processes.


Asunto(s)
Vía de Señalización Hippo , Transducción de Señal , Animales , Humanos , Fosforilación , Proteínas Señalizadoras YAP , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Transformación Celular Neoplásica/metabolismo , Proliferación Celular/fisiología , Fosfoproteínas/metabolismo , Mamíferos
18.
Inflamm Res ; 73(1): 19-33, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38135851

RESUMEN

OBJECTIVE: Salmonella enterica serovar Typhimurium (S. Typhimurium) is a representative model organism for investigating host-pathogen interactions. It was reported that S. Typhimurium spvC gene alleviated intestinal inflammation to aggravate systemic infection, while the precise mechanisms remain unclear. In this study, the influence of spvC on the antibacterial defense of macrophage/neutrophil mediated by gasdermin D (GSDMD) was investigated. METHODS: Mouse macrophage-like cell lines J774A.1 and RAW264.7, neutrophil-like cells derived from HL-60 cells (human promyletic leukemia cell lines) were infected with S. Typhimurium wild type, spvC deletion and complemented strains. Cell death was evaluated by LDH release and Annexin V-FITC/PI staining. Macrophage pyroptosis and neutrophil NETosis were detected by western blotting, live cell imaging and ELISA. Flow cytometry was used to assess the impact of spvC on macrophage-neutrophil cooperation in macrophage (dTHP-1)-neutrophil (dHL-60) co-culture model pretreated with GSDMD inhibitor disulfiram. Wild-type and Gsdmd-/- C57BL/6J mice were utilized for in vivo assay. The degree of phagocytes infiltration and inflammation were analyzed by immunofluorescence and transmission electron microscopy. RESULTS: Here we find that spvC inhibits pyroptosis in macrophages via Caspase-1/Caspase-11 dependent canonical and non-canonical pathways, and restrains neutrophil extracellular traps extrusion in GSDMD-dependent manner. Moreover, spvC could ameliorate macrophages/neutrophils infiltration and cooperation in the inflammatory response mediated by GSDMD to combat Salmonella infection. CONCLUSIONS: Our findings highlight the antibacterial activity of GSDMD in phagocytes and reveal a novel pathogenic mechanism employed by spvC to counteract this host defense, which may shed new light on designing effective therapeutics to control S. Typhimurium infection.


Asunto(s)
Gasderminas , Neutrófilos , Animales , Ratones , Humanos , Ratones Endogámicos C57BL , Salmonella , Macrófagos , Antibacterianos , Inflamación , Caspasas
19.
Pharmgenomics Pers Med ; 16: 1027-1039, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38046381

RESUMEN

Objective: Regimens of S-1-based adjuvant chemotherapy are of great significance in attenuating recurrence risk in postoperative patients with gastric cancer (GC). Kinase insert-domain receptor (KDR) gene plays an essential role in tumor growth and metastasis. This study aimed to investigate the implication of KDR genotyping on the therapeutic outcomes of patients with gastric cancer (GC) who received S-1-based adjuvant chemotherapy. Methods: A total of 169 postoperative GC with pathological staging of II and III and no metastasis who received S-1-based adjuvant chemotherapy were included retrospectively. Peripheral blood specimens were collected and prepared for KDR genotyping and KDR mRNA expression. Correlation between KDR genotype status and prognosis was performed using Kaplan-Meier survival analysis, and multivariate analysis was ultimately adopted using Cox regression analysis. Results: Median disease-free survival (DFS) of the 169 patients with GC was 5.1 years [95% confidence interval (CI): 4.25-5.95] and median overall survival (OS) was 6.7 years (95% CI: 5.44-7.96). Rs2071559 was located at the upstream region, and the prevalence among 169 patients with GC was as follows: AA genotype in 104 cases (61.5%), AG genotype in 57 cases (33.7%), and GG genotype in 8 cases (4.7%), yielding a minor allele frequency of 0.22, which was consistent with Hardy-Weinberg equilibrium (P=0.958). Median DFS of patients with AA and AG/GG genotypes was 6.0 years and 4.0 years, respectively (P=0.002). Additionally, patients with the AA genotype had longer OS than those with the AG/GG genotype [median OS: not reached (NR) vs 5.5 years, P=0.011]. Additionally, KDR mRNA expression was significantly higher in patients with the AG/GG genotype than that in those with the AA genotype (P<0.001). Conclusion: Rs2071559 in KDR gene might be a promising biomarker for evaluating the recurrence risk and OS of patients with GC who received S-1-based adjuvant chemotherapy. This conclusion should be confirmed in randomized clinical trials.

20.
BMC Neurol ; 23(1): 427, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38041003

RESUMEN

PURPOSE: Interictal epileptiform discharges (IEDs) captured in electroencephalography (EEG) have a high diagnostic value for epileptic patients. Extending the recording time may increase the possibility of obtaining IEDs. The purpose of our research was to determine how long it took for various epileptic individuals to receive their first IEDs. METHODS: We retrospectively analyzed patients who were diagnosed with epilepsy and had no anti-seizure medications (ASMs) between September 2018 and March 2019 in the neurology department of the First Affiliated Hospital of Xi'an Jiaotong University. Each individual underwent a 24-h long-term video electroencephalographic monitoring (VEM) procedure. Clinical information including age, gender, age of seizure onset, frequency of seizures, the interval between last seizure and VEM, and results of neuroimaging were gathered. We also calculated the times from the start of the VEM to the first definite IEDs. RESULTS: A total of 241 patients were examined, including 191 with focal-onset epilepsy and 50 with generalized epilepsy. In individuals with focal-onset epilepsy, the median latency to the first IED was 63.0 min (IQR 19.0-299.0 min), as compared to 30.0 min (IQR 12.5-62.0 min) in patients with generalized epilepsy (p < 0.001). The latency to the first IED is significantly related to the age of seizure onset (HR = 0.988, p = 0.049), the interval between last seizure and VEM (HR = 0.998, p = 0.013). But it is not correlated with seizure frequency, gender and age. CONCLUSIONS: IEDs were discovered during 24-h EEG monitoring in 222/241(92.1%) of the epilepsy patients that were included. Compared to focal-onset epilepsy, generalized epilepsy demonstrated a much shorter latency to IED. Patients with late-onset epilepsy or those without recent episodes may require longer EEG monitoring periods.


Asunto(s)
Epilepsias Parciales , Epilepsia Generalizada , Epilepsia , Humanos , Estudios Retrospectivos , Epilepsia/diagnóstico , Epilepsia/tratamiento farmacológico , Electroencefalografía/métodos , Convulsiones
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