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1.
J Am Chem Soc ; 2024 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-39320037

RESUMEN

The practical application of Li-CO2 batteries is significantly hindered by high charge potential and short lifespan, mainly due to sluggish reaction kinetics and inadequate reaction reversibility. Homogeneous catalysts added to the electrolyte provide a promising strategy to address these issues. In this work, the third-generation Grubbs catalyst (G-III), which is efficient for olefin metathesis reactions, has been adopted as a homogeneous catalyst for Li-CO2 batteries. Batteries with G-III exhibited a low overpotential of 0.86 V and a lifespan of 1300 h at a current density of 300 mA g-1. Even at a high current density of 2000 mA g-1, the batteries remained stable for over 300 cycles, with an initial overpotential of 1.11 V. A two-step discharge/charge reaction involving Li2C2O4 as an intermediate was well illustrated, attributed to both low overpotentials and high specific capacity. These findings provide insights into catalyst selection and mechanism analysis for Li-CO2 batteries, offering practical strategies for Li-CO2 battery performance enhancement and practical applications.

2.
BMC Cancer ; 24(1): 1112, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39242532

RESUMEN

BACKGROUND: Hepatocellular carcinoma (HCC), a prevalent primary malignant tumor, is notorious for its high mortality rate. Despite advancements in HCC treatment, patient outcomes remain suboptimal. This study endeavors to assess the potential prognostic significance of POLH-AS1 in HCC. METHODS: In this research, we gathered RNA-Seq information from individuals with HCC in The Cancer Genome Atlas (TCGA). We analyzed the levels of POLH-AS1 expression in both HCC cells and tissues using statistical tests. Additionally, we examined various prognostic factors in HCC using advanced methodologies. Furthermore, we employed Spearman's rank correlation analysis to examine the association between POLH-AS1 expression and the tumor's immune microenvironment. Finally, the functional roles of POLH-AS1 in HCC were validated in two HCC cell lines (HEP3B and HEPG2). RESULTS: Our analysis revealed elevated POLH-AS1 expression across various cancers, including HCC, with heightened expression correlating with HCC progression. Notably, POLH-AS1 expression emerged as a potential biomarker for HCC patient survival and prognosis. Mechanistically, we identified the involvement of POLH-AS1 in tumorigenesis pathways such as herpes simplex virus 1 infection, interactions with neuroactive receptors, and the cAMP signaling pathway. Lastly, inhibition of POLH-AS1 was discovered to hinder the proliferation, invasion and migration of HEP3B and HEPG2 HCC cells. CONCLUSIONS: POLH-AS1 emerges as a promising prognostic biomarker and therapeutic target for HCC, offering potential avenues for enhanced patient management and treatment strategies.


Asunto(s)
Biomarcadores de Tumor , Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/mortalidad , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/mortalidad , Pronóstico , Biomarcadores de Tumor/metabolismo , Biomarcadores de Tumor/genética , Regulación Neoplásica de la Expresión Génica , Microambiente Tumoral , Proliferación Celular , Línea Celular Tumoral , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Movimiento Celular , Células Hep G2
3.
Front Immunol ; 15: 1434463, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39281668

RESUMEN

Functionally bivalent non-covalent Fab dimers (Bi-Fabs) specific for the TCR/CD3 complex promote CD3 signaling on T cells. While comparing functional responses to stimulation with Bi-Fab, F(ab')2 or mAb specific for the same CD3 epitope, we observed fratricide requiring anti-CD3 bridging of adjacent T cells. Surprisingly, anti-CD3 Bi-Fab ranked first in fratricide potency, followed by anti-CD3 F(ab')2 and anti-CD3 mAb. Low resolution structural studies revealed anti-CD3 Bi-Fabs and F(ab')2 adopt similar global shapes with CD3-binding sites oriented outward. However, under molecular dynamic simulations, anti-CD3 Bi-Fabs crosslinked CD3 more rigidly than F(ab')2. Furthermore, molecular modelling of Bi-Fab and F(ab')2 binding to CD3 predicted crosslinking of T cell antigen receptors located in opposing plasma membrane domains, a feature fitting with T cell fratricide observed. Thus, increasing rigidity of Fab-CD3 crosslinking between opposing effector-target pairs may result in stronger T cell effector function. These findings could guide improving clinical performance of bi-specific anti-CD3 drugs.


Asunto(s)
Complejo CD3 , Fragmentos Fab de Inmunoglobulinas , Activación de Linfocitos , Linfocitos T , Complejo CD3/inmunología , Complejo CD3/metabolismo , Humanos , Linfocitos T/inmunología , Linfocitos T/metabolismo , Fragmentos Fab de Inmunoglobulinas/inmunología , Fragmentos Fab de Inmunoglobulinas/metabolismo , Fragmentos Fab de Inmunoglobulinas/química , Activación de Linfocitos/inmunología , Animales , Receptores de Antígenos de Linfocitos T/inmunología , Receptores de Antígenos de Linfocitos T/metabolismo , Unión Proteica , Simulación de Dinámica Molecular , Complejo Receptor-CD3 del Antígeno de Linfocito T/inmunología , Complejo Receptor-CD3 del Antígeno de Linfocito T/metabolismo , Ratones , Anticuerpos Monoclonales/inmunología , Transducción de Señal , Sitios de Unión
4.
Angew Chem Int Ed Engl ; : e202413452, 2024 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-39155243

RESUMEN

Organic-metal coordination materials with rich structural diversity are considered as promising electrode materials for rechargeable sodium-ion batteries. However, the electrochemical performance can be constrained by the limited number of active sites and structural instability under the discharge/charge process. Herein, organometallic polymer microspheres (Fe-PDA-220) with a unique d-π conjugated structure was designed and successfully constructed through a simple synchronous polymerization and coordination reactions. Polymerization of phenylenediamine was initiated by Fe3+ and Fe2+ ions generated synchronously during the polymerization integrated with poly-aminoquinone chains to form Fe-C12N8 active centers. Used as electrode materials for sodium-ion batteries, the distinctive Fe-C bond significantly boosts the structural stability, and the π-d conjugation system could facilitate electron transfer. A high reversible capacity of 345 mAh g-1 was delivered at 0.1 A g-1 and a capacity of 106 mAh g-1 was maintained even after discharged/charged at 1.0 A g-1 for 5000 cycles, outperforming most reported coordination materials. Spectroscopic and electronic analyses revealed that a two-electron reaction occurred per active unit, accompanied by the reversible redox evolution of the C=N groups and Fe ions during  sodiation/desodiation. This work provides a promising and efficient strategy for boosting the electrochemical performance of organic electrode materials by the design of organometallic polymers.

6.
ACS Appl Bio Mater ; 7(5): 3469-3482, 2024 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-38651365

RESUMEN

Bacterial invasion hinders the healing process of wound, leading to the formation of chronic infected wound; meanwhile, the misuse of antibiotics has resulted in the emergence of numerous drug-resistant bacteria. The application of conventional antimicrobial methods and wound treatment techniques is not appropriate for wound dressings. In this paper, quaternized poly(vinyl alcohol) (QPVA) and pomegranate-like copper uniformly doped polydopamine nanoparticles (PDA@Cu) were introduced into a gelatin-oxidized carboxymethyl cellulose system to form a multicomponent synergistic antibacterial hydrogel (GOQ3P3). Polydopamine improves the biocompatibility and prevents the detachment of Cu nanoparticles. It can achieve synergistic antibacterial effects through quaternary ammonium salt-inorganic nanoparticle photothermal treatment under 808 nm near-infrared (NIR) irradiation. It exhibits highly efficient and rapid bactericidal properties against Escherichia coli, Staphylococcus aureus, and MRSA (methicillin-resistant Staphylococcus aureus) with an antibacterial rate close to 100%. The gel scaffold composed of macromolecules gives the hydrogel excellent mechanical properties, adhesive capabilities, self-healing characteristics, biocompatibility, and pH degradation and promotes cell adhesion and migration. In a full-thickness wound healing model infected with MRSA, GOQ3P3 controls inflammatory responses, accelerates collagen deposition, promotes angiogenesis, and enhances wound closure in the wound healing cascade reaction. This study provides a feasible strategy for constructing dressings targeting chronic infection wounds caused by drug-resistant bacteria.


Asunto(s)
Antibacterianos , Materiales Biocompatibles , Carboximetilcelulosa de Sodio , Escherichia coli , Gelatina , Hidrogeles , Ensayo de Materiales , Pruebas de Sensibilidad Microbiana , Cicatrización de Heridas , Antibacterianos/farmacología , Antibacterianos/química , Gelatina/química , Cicatrización de Heridas/efectos de los fármacos , Carboximetilcelulosa de Sodio/química , Carboximetilcelulosa de Sodio/farmacología , Hidrogeles/química , Hidrogeles/farmacología , Escherichia coli/efectos de los fármacos , Animales , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Ratones , Staphylococcus aureus/efectos de los fármacos , Tamaño de la Partícula , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Polímeros/química , Polímeros/farmacología , Indoles/química , Indoles/farmacología , Cobre/química , Cobre/farmacología , Humanos
7.
J Mater Chem B ; 12(10): 2571-2586, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38363109

RESUMEN

Management of diabetic wounds presents a global health challenge due to elevated levels of ROS in the wound microenvironment, persistent dysregulation of inflammation modulation, and limitations in commercially available dressings. Addressing this issue, we have developed a pH-responsive and glucose-sensitive multifunctional hydrogel dressing that dynamically responds to the wound microenvironment and enables on-demand drug release. The dressing incorporates a matrix material based on aminophenylboronic acid-functionalized alginate and a polyhydroxy polymer, alongside an enhancer phase consisting of self-assembled metal-phenol coordination nanospheres formed by tannic acid and iron ions. Using the dynamic borate ester bonds and catechol-metal ion coordination bonds, the dressing exhibits remarkable shape adaptability, self-healing capability, tissue adhesiveness, antioxidant activity, and photothermal responsiveness, without additional curatives or crosslinking agents. As a wound dressing, it elicits macrophage polarization towards an anti-inflammatory phenotype while maintaining long-lasting antimicrobial effects. In a diabetic mouse model of full-thickness wound infections, it effectively mitigated inflammation and vascular damage, significantly expediting the wound healing process with a commendable 97.7% wound closure rate. This work provides a new direction for developing multifunctional smart hydrogel dressings that can accelerate diabetic wound healing for human health.


Asunto(s)
Diabetes Mellitus , Nanosferas , Polifenoles , Humanos , Animales , Ratones , Fenoles , Metales , Alginatos , Inflamación , Hidrogeles/farmacología
8.
Adv Healthc Mater ; 13(14): e2303655, 2024 06.
Artículo en Inglés | MEDLINE | ID: mdl-38265971

RESUMEN

The modulus of traditional biomedical hydrogels increases exponentially meditated by dehydration-stiffing mechanism, which leads to the failure of interface matching between hydrogels and soft tissue wounds. It is found in the study that the dual-solvent gels exhibit dehydration-toughening mechanism with the slowly increasing modulus that are always match the soft tissue wounds. Therefore, dual-solvent glycerol hydrogels (GCFen-gly DGHs) are prepared with hydrophobically modified catechol chitosan (hmCSC) and gelatin based on the supramolecular interactions. GCFen-gly DGHs exhibit excellent water retention capacity with a total solvent content exceeding 80%, permanent skin-like modulus within a range of 0.45 to 4.13 kPa, and stable photothermal antibacterial abilities against S, aureus, E. coli, as well as MRSA. Infectious full-thickness rat skin defect model and tissue section analysis indicate that GCFen-gly DGHs are able to accelerate infectious wound healing by alleviating the inflammatory response, promoting granulation tissue growth, re-epithelialization, collagen deposition, and vascular regeneration. As a result, GCFen-gly DGHs is expected to become the next-generation biological gel materials for infectious wound treatment.


Asunto(s)
Antibacterianos , Quitosano , Hidrogeles , Cicatrización de Heridas , Animales , Hidrogeles/química , Hidrogeles/farmacología , Ratas , Cicatrización de Heridas/efectos de los fármacos , Quitosano/química , Antibacterianos/química , Antibacterianos/farmacología , Ratas Sprague-Dawley , Staphylococcus aureus/efectos de los fármacos , Infección de Heridas/tratamiento farmacológico , Escherichia coli/efectos de los fármacos , Gelatina/química , Masculino , Glicerol/química , Glicerol/farmacología , Piel/efectos de los fármacos , Viscosidad
9.
ACS Appl Bio Mater ; 7(2): 1179-1190, 2024 02 19.
Artículo en Inglés | MEDLINE | ID: mdl-38215047

RESUMEN

The epidermis of a deep burn wound is entirely absent and the dermal tissue sustains significant damage, accompanied by a substantial amount of tissue exudate. Due to the excessively humid environment, the formation of a scab on the wound becomes challenging, leaving it highly vulnerable to external bacterial invasion. In this work, a core-shell dual-drug-loaded nanofiber dressing was prepared by electrospinning technology for the synergistic treatment of a deep burn. The shell layer consists of polycaprolactone and chitosan encapsulating asiaticoside, with the core layer comprising the clathrate of 2-hydroxypropyl-ß-cyclodextrin and curcumin. Upon application to the wound, the dual-drug-loaded nanofiber dressing exhibited rapid release of asiaticoside, stimulating collagen deposition and promoting tissue repair. The core-shell structure and clathrate configuration ensured sustained release of curcumin, providing antibacterial and anti-inflammatory functions for the wound. The mechanical strength, broad-spectrum antibacterial ability, cell proliferation, and adhesion ability of the nanofiber dressing showed its potential as a medical dressing. This dressing also exhibited excellent wound healing promoting effects in the SD rat burn model. This paper provides a strategy for burn wound healing.


Asunto(s)
Quemaduras , Curcumina , Nanofibras , Triterpenos , Ratas , Animales , Nanofibras/uso terapéutico , Nanofibras/química , Curcumina/farmacología , Curcumina/uso terapéutico , Ratas Sprague-Dawley , Quemaduras/tratamiento farmacológico , Antibacterianos/uso terapéutico , Vendajes
10.
Nanomaterials (Basel) ; 13(19)2023 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-37836364

RESUMEN

Perovskite quantum dots (QDs), emerging with excellent bright-green photoluminescence (PL) and a large absorption coefficient, are of great potential for the fabrication of light sources in underwater optical wireless communication systems. However, the instability caused by low formation energy and abundant surface traps is still a major concern for perovskite-based light sources in underwater conditions. Herein, we propose ultra-stable zero dimensional-two dimensional (0D-2D) CsPbBr3 QD/1,4-bis(4-methylstyryl)benzene (p-MSB) nanoplate (NP) heterostructures synthesized via a facile approach at room temperature in air. CsPbBr3 QDs can naturally nucleate on the p-MSB NP toluene solution, and the radiative combination is drastically intensified owing to the electron transfer within the typical type-II heterostructures, leading to a sharply increased PLQY of the heterostructure thin films up to 200% compared with the pristine sample. The passivation of defects within CsPbBr3 QDs can be effectively realized with the existence of p-MSB NPs, and thus the obviously improved PL is steadily witnessed in an ambient atmosphere and thermal environment. Meanwhile, the enhanced humidity stability and a peak EQE of 9.67% suggests a synergetic strategy for concurrently addressing the knotty problems on unsatisfied luminous efficiency and stability of perovskites for high-performance green-emitting optoelectronic devices in underwater applications.

11.
Int J Med Sci ; 20(12): 1600-1615, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37859697

RESUMEN

Uterine Corpus Endometrial Carcinoma (UCEC) is one of the major malignant tumors of the female reproductive system. However, there are limitations in the currently available diagnostic approaches for UCEC. Long non-coding RNAs (lncRNAs) play important roles in regulating biological processes as competitive endogenous RNA (ceRNA) in tumors. To study the potential of lncRNAs as non-invasive diagnostic tumor markers, RNA-sequencing dataset of UCEC patients from The Cancer Genome Atlas was used to identify differentially expressed genes. A lncRNA-miRNA-mRNA ceRNA network was constructed by differentially expressed lncRNAs, miRNAs and miRNAs. Pathway enrichment and functional analysis for the mRNAs in the constructed ceRNA network provide the direction of future research for UCEC by demonstrating the most affected processes and pathways. Seven potential lncRNA biomarkers (C20orf56, LOC100144604, LOC100190940, LOC151534, LOC727677, FLJ35390, LOC158572) were validated in UCEC patients by quantitative real-time PCR. Notably, LOC100190940 and LOC158572 were identified as novel RNA molecules with unknown functions. Receiver operating characteristic (ROC) curve analysis demonstrated that the combined 7 lncRNAs had a high diagnostic value for UCEC patients with area under curve (AUC) of 0.941 (95% CI: 0.875-0.947). Our study highlights the potential of the validated 7 lncRNAs panel as diagnostic biomarkers in UCEC, providing new insights into the UCEC pathogenesis.


Asunto(s)
Neoplasias Endometriales , MicroARNs , ARN Largo no Codificante , Humanos , Femenino , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Redes Reguladoras de Genes/genética , MicroARNs/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Pronóstico , Biomarcadores de Tumor/genética , Regulación Neoplásica de la Expresión Génica , Neoplasias Endometriales/diagnóstico , Neoplasias Endometriales/genética
12.
ACS Appl Mater Interfaces ; 15(37): 44364-44372, 2023 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-37668259

RESUMEN

Metal-organic frameworks (MOFs) with well-defined porous structures and highly active frameworks are considered as promising electrode materials for sodium-ion batteries (SIBs). However, the structure pulverization upon sodiation/desodiation impacts on their practical application in SIBs. To address this issue, poly(p-phenylenediamine) (PPA) was uniformly coated onto the surface of MIL-88A, a typical Fe-based MOF through in situ polymerization initiated by the metal ions (Fe3+) of MIL-88A. Used as an anode material for SIBs, the PPA-coated MIL-88A, denoted as PPA@MIL-88A, showed significantly improved electrochemical performance. A reversible capacity as high as 230 mAh g-1 was achieved at 0.2 A g-1 even after 500 cycles. MIL-88A constructed with electrochemically active Fe3+ and fumaric acid ligands guarantees the high specific capacity, while the PPA polymer coating effectively inhibits the pulverization of MIL-88A. This work provides an efficient strategy for improving the structure and cycling stability of MOFs-based electrode materials.

13.
Front Oncol ; 13: 1192630, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37731632

RESUMEN

Background: To investigate the diagnostic value of shear wave elastography (SWE) and super microvascular imaging (SMI) integrated with the traditional ultrasound breast imaging reporting and data system (BI-RADS) classification in differentiating between benign and malignant breast nodules. Methods: For analysis, 88 patients with 110 breast nodules assessed as BI-RADS 3-5 by conventional ultrasound were selected. SWE and SMI evaluations were conducted separately, and all nodules were verified as benign or malignant ones by pathology. Receiver operating characteristic (ROC) curves were plotted after obtaining quantitative parameters of different shear waves of nodules, including maximum (Emax), mean (Emean), minimum (Emin) Young's modulus, modulus standard deviation (SD), and modulus ratio (Eratio). The best cut-off value, specificity, sensitivity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) for diagnosing malignant nodules employing Emax were obtained, and the diagnostic value of combining Emax and BI-RADS classification was compared. SMI graded nodule based on the Alder blood flow grading standard, whereas the BI-RADS classification was based on microvascular morphology. We assessed the diagnostic value of SMI for breast nodules and investigated the diagnostic efficacy of SWE combined with SMI in differentiating benign and malignant breast nodules with BI-RADS classification 3-5. Results: The adjusted the BI-RADS classification using SMI and SWE technologies promoted the sensitivity, specificity, and accuracy of discriminating benign and malignant breast nodules (P < 0.05). The combination of traditional ultrasound BI-RADS classification with SWE and SMI technologies offered high sensitivity, specificity, accuracy, PPV, and NPV for identifying benign and malignant breast lesions. Moreover, combining SWE and SMI technologies with the adjusted BI-RADS classificationhad the best diagnostic efficacy for distinguishing benign and malignant breast nodules with BI-RADS 3-5. Conclusion: The combination of SWE and SMI with the adjusted BI-RADS classification is a promising diagnostic method for differentiating benign and malignant breast nodules.

14.
Bioact Mater ; 25: 399-414, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37056250

RESUMEN

Natural bone is a composite tissue made of organic and inorganic components, showing piezoelectricity. Whitlockite (WH), which is a natural magnesium-containing calcium phosphate, has attracted great attention in bone formation recently due to its unique piezoelectric property after sintering treatment and sustained release of magnesium ion (Mg2+). Herein, a composite scaffold (denoted as PWH scaffold) composed of piezoelectric WH (PWH) and poly(ε-caprolactone) (PCL) was 3D printed to meet the physiological demands for the regeneration of neuro-vascularized bone tissue, namely, providing endogenous electric field at the defect site. The sustained release of Mg2+ from the PWH scaffold, displaying multiple biological activities, and thus exhibits a strong synergistic effect with the piezoelectricity on inhibiting osteoclast activation, promoting the neurogenic, angiogenic, and osteogenic differentiation of bone marrow mesenchymal stromal cells (BMSCs) in vitro. In a rat calvarial defect model, this PWH scaffold is remarkably conducive to efficient neo-bone formation with rich neurogenic and angiogenic expressions. Overall, this study presents the first example of biomimetic piezoelectric scaffold with sustained Mg2+ release for promoting the regeneration of neuro-vascularized bone tissue in vivo, which offers new insights for regenerative medicine.

15.
Front Public Health ; 10: 1056817, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36544799

RESUMEN

Background: With the trend of world population aging, a good community health care system will determine whether the elderly can get good medical conditions. How to improve the community health care system can study how the behavior of the elderly affects it. Objective: This paper is based on the analysis of the current situation of population aging at home and abroad. Methods: On the premise of analyzing the demand and behavior of elderly people seeking medical treatment and the function of community health service institutions. Literature research was conducted to analyze the influencing factors of community health care needs and elderly people's medical seeking behavior at home and abroad. Then the elderly in Tianjin were investigated by issuing questionnaires, and the law of medical treatment behavior of the elderly in Tianjin was calculated. Combined with the results of relevant investigations abroad, the common phenomenon is summarized. Finally, the analysis method of intelligent medical system is proposed, and the design process of system acquisition module and user usage mode are given. Result: The smart medical system can bring great convenience to the elderly and community healthcare. Discussion: It emphasizes the powerful functions of smart health systems and their future importance for the health care of the elderly.


Asunto(s)
Envejecimiento , Atención a la Salud , Humanos , Anciano , Servicios de Salud Comunitaria , Encuestas y Cuestionarios , Predicción
16.
Quant Imaging Med Surg ; 12(9): 4512-4528, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36060605

RESUMEN

Background: The segmentation of breast ultrasound (US) images has been a challenging task, mainly due to limited data and the inherent image characteristics involved, such as low contrast and speckle noise. Although convolutional neural network-based (CNN-based) methods have made significant progress over the past decade, they lack the ability to model long-range interactions. Recently, the transformer method has been successfully applied to the tasks of computer vision. It has a strong ability to capture distant interactions. However, most transformer-based methods with excellent performance rely on pre-training on large datasets, making it infeasible to directly apply them to medical images analysis, especially that of breast US images with limited high-quality labels. Therefore, it is of great significance to find a robust and efficient transformer-based method for use on small breast US image datasets. Methods: We developed a dilated transformer (DT) method which mainly uses the proposed residual axial attention layers to build encoder blocks and the introduced dilation module (DM) to further increase the receptive field. We evaluated the proposed method on 2 breast US image datasets using the 5-fold cross-validation method. Dataset A was a public dataset with 562 images, while dataset B was a private dataset with 878 images. Ground truth (GT) was delineated by 2 radiologists with more than 5 years of experience. The evaluation was followed by related ablation experiments. Results: The DT was found to be comparable with the state-of-the-art (SOTA) CNN-based method and outperformed the related transformer-based method, medical transformer (MT), on both datasets. Especially on dataset B, the DT outperformed the MT on metrics of Jaccard index (JI) and Dice similarity coefficient (DSC) by 2.67% and 4.68%, respectively. Meanwhile, when compared with Unet, the DT improved JI and DSC by 4.89% and 4.66%, respectively. Moreover, the results of the ablation experiments showed that each add-on part of the DT is important and contributes to the segmentation accuracy. Conclusions: The proposed transformer-based method could achieve advanced segmentation performance on different small breast US image datasets without pretraining.

17.
Phys Med Biol ; 67(17)2022 09 02.
Artículo en Inglés | MEDLINE | ID: mdl-35961304

RESUMEN

Objective.This paper proposes an automatic breast tumor segmentation method for two-dimensional (2D) ultrasound images, which is significantly more accurate, robust, and adaptable than common deep learning models on small datasets.Approach.A generalized joint training and refined segmentation framework (JR) was established, involving a joint training module (Jmodule) and a refined segmentation module (Rmodule). InJmodule, two segmentation networks are trained simultaneously, under the guidance of the proposed Jocor for Segmentation (JFS) algorithm. InRmodule, the output ofJmoduleis refined by the proposed area first (AF) algorithm, and marked watershed (MW) algorithm. The AF mainly reduces false positives, which arise easily from the inherent features of breast ultrasound images, in the light of the area, distance, average radical derivative (ARD) and radical gradient index (RGI) of candidate contours. Meanwhile, the MW avoids over-segmentation, and refines segmentation results. To verify its performance, the JR framework was evaluated on three breast ultrasound image datasets. Image dataset A contains 1036 images from local hospitals. Image datasets B and C are two public datasets, containing 562 images and 163 images, respectively. The evaluation was followed by related ablation experiments.Main results.The JR outperformed the other state-of-the-art (SOTA) methods on the three image datasets, especially on image dataset B. Compared with the SOTA methods, the JR improved true positive ratio (TPR) and Jaccard index (JI) by 1.5% and 3.2%, respectively, and reduces (false positive ratio) FPR by 3.7% on image dataset B. The results of the ablation experiments show that each component of the JR matters, and contributes to the segmentation accuracy, particularly in the reduction of false positives.Significance.This study successfully combines traditional segmentation methods with deep learning models. The proposed method can segment small-scale breast ultrasound image datasets efficiently and effectively, with excellent generalization performance.


Asunto(s)
Neoplasias de la Mama , Ultrasonografía Mamaria , Algoritmos , Neoplasias de la Mama/diagnóstico por imagen , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Ultrasonografía
18.
Macromol Rapid Commun ; 43(21): e2200456, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35842914

RESUMEN

In recent years, natural polymer-based electrospun fibers (EFs) with huge specific surface area, good biocompatibility, and biological activity obtained from electrospinning process exhibit tremendous vitality in the field of biomedical areas. Herein, the parameters of electrospinning from two perspectives, polymer solution such as solvent, polymeric relative molecular mass, concentration, viscosity, and conductivity of the solution, and electrospinning process such as spinning voltage, spinning flow rate, needle tip to collector distance, temperature, and humidity are first detailed. Next, the raw materials consisting of polysaccharides such as cellulose, hyaluronic acid, alginate, and chitosan as well as proteins such as collagen, gelatin, silk fibroin, and keratin are summarized. The preparation method and related characteristics of EFs with multistage structures such as porous, core-shell, Janus, bamboo-like and other structures are introduced. The biomedical applications of these natural polymer-based EFs mainly including tissue engineering, drug sustained release, wound dressings, and biomedical sensors are systematically recapitulated. Finally, the outlook on natural EFs is further proposed.


Asunto(s)
Quitosano , Fibroínas , Polímeros , Ingeniería de Tejidos , Fibroínas/química , Gelatina/química , Quitosano/química
19.
Carbohydr Polym ; 291: 119574, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-35698393

RESUMEN

Unfortunately hemorrhage and its complications (e.g. anemia, organ failure, and hypothermia) induced by traumatic injury, surgery, and disorders of bleeding play an all too familiar role in human morbidity and mortality. Therefore, it is difficult to overstate the importance of better understanding the role of polysaccharides in advanced hemostatic dressings (HDs). This review includes consideration of polysaccharide hemostatic dressing mechanism of action, relative efficacy, cost and safety. Polysaccharide-based HDs are widely used in management not only of external and internal bleeding but also of massive hemorrhage. These polysaccharide-based HDs have been shown to be effective in both compressible and non-compressible hemorrhage. Hemostatic dressings are designed with different principles depending on location and extent of injury. This review focuses on polysaccharide HD design and associated hemostatic mechanisms. It addresses current issues, challenges, and future perspectives.


Asunto(s)
Quitosano , Hemostáticos , Alginatos/uso terapéutico , Vendajes , Celulosa/farmacología , Celulosa/uso terapéutico , Quitosano/farmacología , Quitosano/uso terapéutico , Hemorragia/tratamiento farmacológico , Hemostáticos/farmacología , Hemostáticos/uso terapéutico , Humanos , Polisacáridos/farmacología , Polisacáridos/uso terapéutico , Almidón
20.
Int J Clin Pract ; 2022: 8775641, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35685609

RESUMEN

Objective: We describe the clinical manifestations of supra-large range nonperfusion area (SLRNPA) in diabetic retinopathy (DR). Methods: This was a retrospective case-control study. A total of 260 eyes of 236 patients with DR who underwent pars plana vitrectomy in the Department of Ophthalmology of Qingdao Municipal Hospital from February 2016 to June 2019 were enrolled. Fundus fluorescein angiography was performed after surgery to determine whether SLRNPA or non-SLRNPA in DR was present. All demographic and clinical data were carefully collected. Results: Forty-one eyes of 22 patients were diagnosed with SLRNPA in DR (15.77% of all eyes). Compared to non-SLRNPA, SLRNPA patients were more likely to be male and younger with earlier DR onset, a smoking history, other comorbidities, and a higher HbA1c level. SLRNPA in DR eyes exhibited more neovascular glaucoma (NVG) and diabetic keratopathy (DK) than did other eyes. Such eyes were more likely to require anti-VEGF therapy before surgery or a silicone oil or a gas tamponade during surgery and to suffer from persistent corneal epithelial erosion and NVG recurrence after surgery. Conclusions: SLRNPA in DR is a severe status of DR. Treatment for DR patients with SLRNPA is difficult, and the prognosis is poor, so clinicians must thus pay more attention to SLRNPA in DR.


Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Estudios Retrospectivos , Vitrectomía
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