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4.
Nanomaterials (Basel) ; 13(21)2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-37947731

RESUMEN

Two-dimensional (2D) nanomaterial-based membranes feature attractive properties for molecular separation and transport, which exhibit huge potential in various chemical processes. However, the low permeability and bio-fouling of the MXene membrane in water treatment become huge obstacles to its practical application. Herein, a highly permselective and anti-bacterial 2D nanofiltration membrane is fabricated by intercalating a polycation of polydiallyldimethylammonium chloride (PDDA) into the Ti3C2Tx MXene laminar architecture through a facile and patternable electrostatic assembly strategy. As a result, the as-fabricated Ti3C2Tx/PDDA composite membrane exhibits higher water permeance up to 73.4 L m-2 h-1 with a rejection above 94.6% for MgCl2. The resultant membrane simultaneously possesses good resistance to swelling and long-term stability in water environments, even after 8 h. Additionally, the Ti3C2Tx/PDDA membrane also demonstrates a high flux recovery ratio of nearly 96.1% to bovine serum albumin proteins after being cleaned. More importantly, the current membrane shows excellent anti-adhesive and anti-microbial activity against Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus), with inhibition rates of 90% and 95% against E. coli and S. aureus, respectively. This holds great potential for the application of the polyelectrolyte-intercalated MXene membrane in serving as a promising platform to separate molecules and/or ions in an aquatic environment.

5.
Sensors (Basel) ; 23(22)2023 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-38005490

RESUMEN

As a fundamental computer vision task, instance segmentation is widely used in the field of autonomous driving because it can perform both instance-level distinction and pixel-level segmentation. We propose CompleteInst based on QueryInst as a solution to the problems of missed detection with a network structure designed from the feature level and the instance level. At the feature level, we propose Global Pyramid Networks (GPN) to collect global information of missed instances. Then, we introduce the semantic branch to complete the semantic features of the missed instances. At the instance level, we implement the query-based optimal transport assignment (OTA-Query) sample allocation strategy which enhances the quality of positive samples of missed instances. Both the semantic branch and OTA-Query are parallel, meaning that there is no interference between stages, and they are compatible with the parallel supervision mechanism of QueryInst. We also compare their performance to that of non-parallel structures, highlighting the superiority of the proposed parallel structure. Experiments were conducted on the Cityscapes and COCO dataset, and the recall of CompleteInst reached 56.7% and 54.2%, a 3.5% and 3.2% improvement over the baseline, outperforming other methods.

6.
Front Cell Infect Microbiol ; 13: 1135013, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37868346

RESUMEN

Cryo-electron tomography (cryo-ET) plays a critical role in imaging microorganisms in situ in terms of further analyzing the working mechanisms of viruses and drug exploitation, among others. A data processing workflow for cryo-ET has been developed to reconstruct three-dimensional density maps and further build atomic models from a tilt series of two-dimensional projections. Low signal-to-noise ratio (SNR) and missing wedge are two major factors that make the reconstruction procedure challenging. Because only few near-atomic resolution structures have been reconstructed in cryo-ET, there is still much room to design new approaches to improve universal reconstruction resolutions. This review summarizes classical mathematical models and deep learning methods among general reconstruction steps. Moreover, we also discuss current limitations and prospects. This review can provide software and methods for each step of the entire procedure from tilt series by cryo-ET to 3D atomic structures. In addition, it can also help more experts in various fields comprehend a recent research trend in cryo-ET. Furthermore, we hope that more researchers can collaborate in developing computational methods and mathematical models for high-resolution three-dimensional structures from cryo-ET datasets.


Asunto(s)
Tomografía con Microscopio Electrónico , Virus , Tomografía con Microscopio Electrónico/métodos , Microscopía por Crioelectrón/métodos , Programas Informáticos , Flujo de Trabajo , Procesamiento de Imagen Asistido por Computador/métodos
7.
Drug Dev Res ; 84(7): 1395-1410, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37583266

RESUMEN

Src homology-2 domain-containing protein tyrosine phosphatase-2 (SHP2) is a key regulatory factor in the cell cycle and its activating mutations play an important role in the development of various cancers, making it an important target for antitumor drugs. Due to the highly conserved amino acid sequence and positively charged nature of the active site of SHP2, it is difficult to discover inhibitors with high affinity for the catalytic site of SHP2 and sufficient cell permeability, making it considered an "undruggable" target. However, the discovery of allosteric regulation mechanisms provides new opportunities for transforming undruggable targets into druggable ones. Given the limitations of orthosteric inhibitors, SHP2 allosteric inhibitors have become a more selective and safer research direction. In this review, we elucidate the oncogenic mechanism of SHP2 and summarize the discovery methods of SHP2 allosteric inhibitors, providing new strategies for the design and improvement of SHP2 allosteric inhibitors.


Asunto(s)
Antineoplásicos , Neoplasias , Humanos , Proteína Tirosina Fosfatasa no Receptora Tipo 11/química , Proteína Tirosina Fosfatasa no Receptora Tipo 11/genética , Proteína Tirosina Fosfatasa no Receptora Tipo 11/metabolismo , Neoplasias/tratamiento farmacológico , Secuencia de Aminoácidos , Antineoplásicos/uso terapéutico , Ciclo Celular , Inhibidores Enzimáticos/farmacología
8.
Front Psychol ; 14: 1150998, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37260960

RESUMEN

Objective: The study aimed to analyze the current status and reasons for the neglect of the psychological need of patients with common skin diseases. Methods: This cross-sectional study was conducted in China using an online self-assessment questionnaire distributed via social media. Demographic, clinical and psychological data were collected, and the main outcomes, i.e., depression (evaluated using the 9-item Patient Health Questionnaire, PHQ-9) and anxiety (evaluated using Generalized Anxiety Disorder-7, GAD-7). Multivariate regression analysis was used for the prediction of variates of mental health service seeking behaviors. Results: A total of 1,010 patients participated in the survey, and 273 (27.0%) patients met the "with need" criteria, i.e., having the need for mental health intervention but not being treated. In the multivariate regression model, income (OR = 0.80, 95%CI: 0.65-0.99), duration of disease (OR = 0.68, 95%CI: 0.49-0.95) and suicide ideation (OR = 2.10, 95%CI: 1.14-3.87) were significant factors. For patients who did not receive mental health care, the lack of knowledge about the availability of mental health services, lack of knowledge of where to seek help, concerns about the side effects of treatment, failure to seek treatment for severe skin diseases, and absence of current psychological distress were associated with their need for psychological intervention. Conclusion: This study examined the current status of the need for psychological intervention and the reasons why the need was unmet in patients with skin diseases. Due to the confusion and a lack of knowledge about their mental health issues, mental health services are often underutilized.

9.
Nucleic Acids Res ; 51(D1): D1312-D1324, 2023 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-36300629

RESUMEN

With the exponential growth of multi-omics data, its integration and utilization have brought unprecedented opportunities for the interpretation of gene regulation mechanisms and the comprehensive analyses of biological systems. IAnimal (https://ianimal.pro/), a cross-species, multi-omics knowledgebase, was developed to improve the utilization of massive public data and simplify the integration of multi-omics information to mine the genetic mechanisms of objective traits. Currently, IAnimal provides 61 191 individual omics data of genome (WGS), transcriptome (RNA-Seq), epigenome (ChIP-Seq, ATAC-Seq) and genome annotation information for 21 species, such as mice, pigs, cattle, chickens, and macaques. The scale of its total clean data has reached 846.46 TB. To better understand the biological significance of omics information, a deep learning model for IAnimal was built based on BioBERT and AutoNER to mine 'gene' and 'trait' entities from 2 794 237 abstracts, which has practical significance for comprehending how each omics layer regulates genes to affect traits. By means of user-friendly web interfaces, flexible data application programming interfaces, and abundant functional modules, IAnimal enables users to easily query, mine, and visualize characteristics in various omics, and to infer how genes play biological roles under the influence of various omics layers.


Asunto(s)
Bases de Datos Genéticas , Animales , Regulación de la Expresión Génica , Genoma , Bases del Conocimiento , Programas Informáticos , Multiómica
10.
Sci Bull (Beijing) ; 67(15): 1522-1525, 2022 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-36546275
11.
Int J Nanomedicine ; 17: 6157-6180, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36523423

RESUMEN

Non-small cell lung cancer (NSCLC) is a global burden leading to millions of deaths worldwide every year. Nanomedicine refers to the use of materials at the nanoscale for drug delivery and subsequent therapeutic approaches in cancer. Carbon nanotubes (CNTs) are widely used as nanocarriers for therapeutic molecules such as plasmids, siRNAs, antisense agents, aptamers and molecules related to the immunotherapy for several cancers. They are usually functionalized and loaded with standard drug molecules to improve their therapeutic efficiency. Functionalization and drug loading possibly decrease the genotoxic and carcinogenic potential of CNTs. In addition, the targeted cytotoxic properties of the drug improve and undesired toxicity decreases after drug loading and/or conjugation with proteins, including antibodies. For intended drug delivery, a lysosomal pH of 5.5 is more suitable and effective for the slow and extended release of cytotoxic drugs than a physiological of pH 7.4. Remarkably, CNTs possess intrinsic antitumor properties and are usually internalized by endocytosis. After being internalized, several mechanisms are involved in the therapeutic and carcinogenic effects of CNTs. They are generally safe for therapy, and their toxicity profile remains dependent on their physicochemical properties. Moreover, the dose, route, duration of exposure, surface properties and degradative potential determine the toxicity outcomes of CNTs locally or systemically. In summary, the use of CNTs in drug delivery and NSCLC therapy, as well as their genotoxic and carcinogenic potential and the possible mechanisms, has been discussed in this review. The therapeutic index is generally high for NSCLC cells treated with drug-loaded CNTs; therefore, they are effective carriers in implementing targeted therapy for NSCLC.


Asunto(s)
Antineoplásicos , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Nanotubos de Carbono , Humanos , Nanotubos de Carbono/química , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinógenos , Neoplasias Pulmonares/tratamiento farmacológico , Antineoplásicos/farmacología , Carcinogénesis , Biomarcadores , Portadores de Fármacos/química
12.
Front Plant Sci ; 13: 1021398, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36420030

RESUMEN

Accurate and rapid identification of the effective number of panicles per unit area is crucial for the assessment of rice yield. As part of agricultural development, manual observation of effective panicles in the paddy field is being replaced by unmanned aerial vehicle (UAV) imaging combined with target detection modeling. However, UAV images of panicles of curved hybrid Indica rice in complex field environments are characterized by overlapping, blocking, and dense distribution, imposing challenges on rice panicle detection models. This paper proposes a universal curved panicle detection method by combining UAV images of different types of hybrid Indica rice panicles (leaf-above-spike, spike-above-leaf, and middle type) from four ecological sites using an improved You Only Look Once version 4 (YOLOv4) model. MobileNetv2 is used as the backbone feature extraction network based on a lightweight model in addition to a focal loss and convolutional block attention module for improved detection of curved rice panicles of different varieties. Moreover, soft non-maximum suppression is used to address rice panicle occlusion in the dataset. This model yields a single image detection rate of 44.46 FPS, and mean average precision, recall, and F1 values of 90.32%, 82.36%, and 0.89%, respectively. This represents an increase of 6.2%, 0.12%, and 16.24% from those of the original YOLOv4 model, respectively. The model exhibits superior performance in identifying different strain types in mixed and independent datasets, indicating its feasibility as a general model for detection of different types of rice panicles in the heading stage.

13.
Rep Prog Phys ; 86(2)2022 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-36395499

RESUMEN

The past decades witnessed the golden era of hadron physics. Many excited open heavy flavor mesons and baryons have been observed since 2017. We shall provide an updated review of the recent experimental and theoretical progresses in this active field. Besides the conventional heavy hadrons, we shall also review the recently observed open heavy flavor tetraquark statesX(2900) andTcc+(3875)as well as the hidden heavy flavor multiquark statesX(6900),Pcs(4459)0,Zcs(3985)-,Zcs(4000)+, andZcs(4220)+. We will also cover the recent progresses on the glueballs and light hybrid mesons, which are the direct manifestations of the non-AbelianSU(3) gauge interaction of the Quantum Chromodynamics in the low-energy region.

14.
Phys Rev Lett ; 128(11): 112001, 2022 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-35363019

RESUMEN

A novel framework is proposed to extract near-threshold resonant states from finite-volume energy levels of lattice QCD and is applied to elucidate structures of the positive parity D_{s}. The quark model, the quark-pair-creation mechanism and D^{(*)}K interaction are incorporated into the Hamiltonian effective field theory. The bare 1^{+} cs[over ¯] states are almost purely given by the states with heavy-quark spin bases. The physical D_{s0}^{*}(2317) and D_{s1}^{*}(2460) are the mixtures of bare cs[over ¯] core and D^{(*)}K component, while the D_{s1}^{*}(2536) and D_{s2}^{*}(2573) are almost dominated by bare cs[over ¯]. Furthermore, our model reproduces the clear level crossing of the D_{s1}^{*}(2536) with the scattering state at a finite volume.

15.
Polymers (Basel) ; 14(6)2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-35335498

RESUMEN

Polymeric membranes, such as polyamide thin film composite membranes, have gained increasing popularity in wastewater treatment, seawater desalination, as well as the purification and concentration of chemicals for their high salt-rejection and water flux properties. Membrane biofouling originates from the attachment or deposition of organic macromolecules/microorganisms and leads to an increased operating pressure and shortened service life and has greatly limited the application of polymeric membranes. Over the past few years, numerous strategies and materials were developed with the aim to control membrane biofouling. In this review, the formation process, influence factors, and consequences of membrane biofouling are systematically summarized. Additionally, the specific strategies for mitigating membrane biofouling including anchoring of hydrophilic monomers, the incorporation of inorganic antimicrobial nanoparticles, coating/grafting of cationic bactericidal polymers, and the design of multifunctional material integrated multiple anti-biofouling mechanisms, are highlighted. Finally, perspectives on the challenges and opportunities in anti-biofouling polymeric membranes are shared, shedding light on the development of even better anti-biofouling materials in near future.

16.
Zool Res ; 42(4): 502-513, 2021 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-34254744

RESUMEN

Persistent uplift means the Qinghai-Tibet Plateau (QTP) is an ideal natural laboratory to investigate genome evolution and adaptation within highland environments. However, how paleogeographic and paleoclimatic events influence the genome and population of endemic fish species remains unclear. Glyptosternon maculatum is an ancient endemic fish found on the QTP and the only critically endangered species in the Sisoridae family. Here, we found that major transposons in the G. maculatum genome showed episodic bursts, consistent with contemporaneous geological and climatic events during the QTP formation. Notably, histone genes showed significant expansion in the G. maculatum genome, which may be mediated by long interspersed nuclear elements (LINE) repetitive element duplications. Population analysis showed that ancestral G. maculatum populations experienced two significant depressions 2.6 million years ago (Mya) and 10 000 years ago, exhibiting excellent synchronization with Quaternary glaciation and the Younger Dryas, respectively. Thus, we propose that paleogeography and paleoclimate were dominating driving forces for population dynamics in endemic fish on the QTP. Tectonic movements and temperature fluctuation likely destroyed the habitat and disrupted the drainage connectivity among populations. These factors may have caused severe bottlenecks and limited migration among ancestral G. maculatum populations, resulting in the low genetic diversity and endangered status of the species today.


Asunto(s)
Adaptación Fisiológica , Evolución Biológica , Ecosistema , Peces/genética , Genoma , Animales , Clima , Tibet
17.
Bioengineered ; 12(1): 2398-2409, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34130594

RESUMEN

Ginsenoside Rg3, a natural compound, has been reported to function as an anticancer agent for hepatoma carcinoma, while the mechanisms underlying the anticancer effects are not clear. Therefore, the objective of our study was to explore the impact of RG3 on cell migration and invasion by regulating the lncRNA HOX antisense intergenic (HOTAIR) expression involving PI3K/AKT signaling pathway. qRT-PCR was utilized to measure the mRNA expression of HOTAIR. Furthermore, HOTAIR overexpression plasmids were transfected to SMMC-7721 and SK-Hep-1 cells. Additionally, MTT assay was used to evaluate the proliferation of transfected cells. The scratch and transwell assays were used to determine the migration and invasion ability of the cell. The protein levels were determined with Western blot. lncRNA HOTAIR was overexpressed in SMMC-7721 and SK-Hep-1 cells. Ginsenoside-Rg3 reduced the level of lncRNA HOTAIR. Overexpressed lncRNA HOTAIR offset ginsenoside-Rg3 inhibited proliferation, migration and invasion of HCC cells. Furthermore, ginsenoside-Rg3 decreased the expression of p-AKT, p-PI3K, matrix metalloproteinase-2 (MMP2) and matrix metalloproteinase-9 (MMP9), which was reversed after the treatment of HOTAIR. LncRNA HOTAIR was overexpressed in SMMC-7721 cells. Ginsenoside-Rg3 could reduce the expression of lncRNA HOTAIR, resulting in the inhibited cell proliferation, migration and invasion. Furthermore, ginsenoside-Rg3 inhibited cell proliferation and invasion ability through the PI3k/AKT pathway. Thus, ginsenoside-Rg3 might be a potential and effective treatment for HCC.


Asunto(s)
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Regulación Neoplásica de la Expresión Génica , Ginsenósidos/farmacología , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , ARN Largo no Codificante/genética , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Movimiento Celular/genética , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Ginsenósidos/química , Células HEK293 , Humanos , Metaloproteinasa 2 de la Matriz/genética , Metaloproteinasa 9 de la Matriz/genética , Invasividad Neoplásica , Fosfatidilinositol 3-Quinasas/metabolismo , Fosforilación/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Largo no Codificante/metabolismo
18.
J Anim Sci ; 99(2)2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33493272

RESUMEN

Despite the broad variety of available microRNA (miRNA) research tools and methods, their application to the identification, annotation, and target prediction of miRNAs in nonmodel organisms is still limited. In this study, we collected nearly all public sRNA-seq data to improve the annotation for known miRNAs and identify novel miRNAs that have not been annotated in pigs (Sus scrofa). We newly annotated 210 mature sequences in known miRNAs and found that 43 of the known miRNA precursors were problematic due to redundant/missing annotations or incorrect sequences. We also predicted 811 novel miRNAs with high confidence, which was twice the current number of known miRNAs for pigs in miRBase. In addition, we proposed a correlation-based strategy to predict target genes for miRNAs by using a large amount of sRNA-seq and RNA-seq data. We found that the correlation-based strategy provided additional evidence of expression compared with traditional target prediction methods. The correlation-based strategy also identified the regulatory pairs that were controlled by nonbinding sites with a particular pattern, which provided abundant complementarity for studying the mechanism of miRNAs that regulate gene expression. In summary, our study improved the annotation of known miRNAs, identified a large number of novel miRNAs, and predicted target genes for all pig miRNAs by using massive public data. This large data-based strategy is also applicable for other nonmodel organisms with incomplete annotation information.


Asunto(s)
MicroARNs , Animales , Genoma , Secuenciación de Nucleótidos de Alto Rendimiento/veterinaria , MicroARNs/genética , Porcinos/genética
19.
Sci Bull (Beijing) ; 66(13): 1288-1295, 2021 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-36654150

RESUMEN

In this work, we investigate the SU(3) flavor symmetry, heavy quark spin symmetry and their breaking effects in the di-meson systems. We prove the existence of the [Formula: see text] , [Formula: see text] , and [Formula: see text] bound states as the consequence of two prerequisites in the SU(3) flavor symmetry and heavy quark spin symmetry. The first prerequisite, the X(3872) as the weakly D‾∗D/D‾D∗ bound state is supported by its mass and decay branching ratios. The second prerequisite, the existence of the [Formula: see text] bound state is supported by the lattice QCD calculation and the observation of χc0(3930) by the LHCb Collaboration. We hope the future experimental analyses can search for these bound states in the B→D(s)(*)D‾(s)(*)h processes (h denotes the light hadrons). The [Formula: see text] bound state is also expected to be reconstructed in the J/ψϕ final state in the B→J/ψϕK decay.

20.
Sci Bull (Beijing) ; 66(20): 2065-2071, 2021 10 30.
Artículo en Inglés | MEDLINE | ID: mdl-36654264

RESUMEN

Recently, the hidden charm tetraquark states Zcs(3985) and Zcs(4000) with strangeness were observed by the BESIII and LHCb collaborations, respectively, which are great breakthroughs for exploring exotic quantum chromodynamics (QCD) structures. The first and foremost question is whether they are the same state. In this work, we explore the implications of the narrower state Zcs(3985) in BESIII and the wider one Zcs(4000) in LHCb as two different states. Within a solvable nonrelativistic effective field theory, we include the possible violations of heavy quark spin symmetry and SU(3) flavor symmetry in a comprehensive approach. If Zcs(3985) and Zcs(4000) are two different states, our results show that Zcs(4000)/Zcs(3985) is the pure (|D‾s∗D〉+/-|D‾sD∗〉)/2 state, and the SU(3) flavor partner of Zc(3900) is Zcs(4000) rather than the Zcs(3985). Another two important consequences are the existence of a tensor D‾s∗D∗ resonance with mass about 4126 MeV and width 13 MeV, and the suppression of the decay mode Zcs(3985)→J/ψK. The two consequences can be tested in experiments and distinguish the two-state interpretation from the one-state scheme.


Asunto(s)
Altruismo , Existencialismo , Alimentos , Vibración
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