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1.
Artigo em Chinês | MEDLINE | ID: mdl-34628833

RESUMO

Objective:To explore the diagnostic efficacy of ultrasound-guided fine needle aspiration cytology(US-FNAC) for thyroid nodules ≥1 cm, and the effect of Hashimoto's thyroiditis(HT) on it. Methods:The clinical data of 1027 cases of thyroid nodules ≥ 1 cm were retrospectively analyzed. Two-dimensional ultrasound, US-FNAC and BRAFV600E gene testing were performed. The postoperative pathological results were used as the criterion. The two dimensional ultrasound examination, clinical characteristics, follow-up results, and BRAFV600E were used to diagnosis for unoperated patients. The diagnostic efficiency of US-FNAC in HT(+) group and HT(-) group was compared, and the factors affecting the diagnostic efficiency were analyzed. Results:Of the 1027 nodules, the cytological results were nondiagnostic/unsatisfactory in 73 nodules(7.1%), benign in 282(27.5%), atypia of undetermined significance/follicular lesion of undetermined significance in 230(22.4%), follicular neoplasm/suspicious for a follicular neoplasm in 20(1.9%), suspicious for malignancy in 120(11.7%), and malignant in 302(29.4%). 515 cases underwent surgery. Among them, 495 were malignant and 20 were benign. 512 cases continued to be followed up without surgery, and the BRAFV600E of them were wild type. Combined with the two dimensional ultrasound examination, clinical features, and follow-up results, they were judged to be benign. The accuracy, sensitivity, specificity, positive predictive value, negative predictive value, false positive rate and the false negative rate the of US-FNAC were 98.7%, 98.4%, 99.3%, 99.5%, 97.5%, 0.7% and 1.6%, respectively. The accuracy, sensitivity and negative predictive value of the HT(+) group were 95.5%, 95.4% and 82.8%, respectively, which were lower than that of HT(-) group (99.5%, 99.4%, 99.2% )(P=0.001, 0.018, P<0.001). The false negative rate of the HT(+) group was 4.6%, higher than 0.6% of the HT(-) group(P=0.018), and HT was an risk factor for increased FNR(OR=7.596, 95%CI: 1.452-39.740). Conclusion:US-FNAC is an effective method for the diagnosis of thyroid nodules and it has high sensitivity and specificity in ≥ 1 cm nodules. However, the combination of HT reduces the diagnostic accuracy and HT is a risk factor for increased false negative rate.


Assuntos
Doença de Hashimoto , Nódulo da Glândula Tireoide , Biópsia por Agulha Fina , Doença de Hashimoto/diagnóstico por imagem , Humanos , Estudos Retrospectivos , Sensibilidade e Especificidade , Nódulo da Glândula Tireoide/diagnóstico por imagem , Ultrassonografia de Intervenção
2.
Philos Trans A Math Phys Eng Sci ; 379(2206): 20200331, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34334022

RESUMO

Chitin is one of the most abundant biopolymers, and it has adopted many different structural conformations using a combination of different natural processes like biopolymerization, crystallization and non-equilibrium self-assembly. This leads to a number of striking physical effects like complex light scattering and polarization as well as unique mechanical properties. In doing so, chitin uses a fine balance between the highly ordered chain conformations in the nanofibrils and random disordered structures. In this opinion piece, we discuss the structural hierarchy of chitin, its crystalline states and the natural biosynthesis processes to create such specific structures and diversity. Among the examples we explored, the unified question arises from the generation of completely different bioarchitectures like the Christmas tree-like nanostructures, gyroids or helicoidal geometries using similar dynamic non-equilibrium growth processes. Understanding the in vivo development of such structures from gene expressions, enzymatic activities as well as the chemical matrix employed in different stages of the biosynthesis will allow us to shift the material design paradigms. Certainly, the complexity of the biology requires a collaborative and multi-disciplinary research effort. For the future's advanced technologies, using chitin will ultimately drive many innovations and alternatives using biomimicry in materials science. This article is part of the theme issue 'Bio-derived and bioinspired sustainable advanced materials for emerging technologies (part 1)'.

3.
Int J Biol Macromol ; 185: 1022-1035, 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34197859

RESUMO

Biochemical modification can endow the surface of implants with superior biological activity. Herein, silk fibroin (SF) protein and its anionic derivative peptides (Cs) were covalently immobilized onto a titanium implant surface via a polydopamine layer. The successful conjugation of SF and Cs was revealed by X-ray photoelectron spectroscopy (XPS), field-emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM), and contact angle measurements. The addition of Cs prevented the conformational transition of silk fibroin to silk II. The deposition of apatite on its surface was significantly accelerated, and the bioactive composite coating was observed to enhance protein adsorption and cell proliferation. More importantly, it also promoted the osteogenic differentiation of bone marrow stem cells (BMSCs) for the quantitative and qualitative detection of alkaline phosphatase (ALP) and alizarin red (ARS). Overall, the stable performance and enhanced osteogenic property of the composite coating promote an extensive application for clinical titanium-based implants.


Assuntos
Fibroínas/farmacologia , Indóis/química , Células-Tronco Mesenquimais/citologia , Osteogênese/efeitos dos fármacos , Polímeros/química , Titânio/química , Adsorção , Animais , Apatitas/química , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Fibroínas/química , Células-Tronco Mesenquimais/efeitos dos fármacos , Camundongos , Microscopia de Força Atômica , Oxirredução , Peptídeos/química , Peptídeos/farmacologia , Espectroscopia Fotoeletrônica
4.
BMC Med Imaging ; 21(1): 97, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-34098896

RESUMO

BACKGROUND: Conventional dynamic contrast enhanced (DCE) magnetic resonance (MR) hardly achieves a good imaging performance of arteries and lymph nodes in the breast area. Therefore, a new imaging method is needed for the assessment of breast arteries and lymph nodes. METHODS: We performed prospective research. The research included 52 patients aged from 25 to 64 between June 2019 and April 2020. The isotropic e-THRIVE sequence scanned in the coronal direction after DCE-THRIVE. Reconstructed images obtained by DCE-THRIVE and the coronal e-THRIVE were compared mainly in terms of the completeness of the lateral thoracic artery, thoracodorsal artery, and lymph nodes. We proposed a criterion for evaluating image quality. According to the criterion, images were assigned a score from 1 to 5 according to the grade from low to high. Two board-certified doctors evaluated images individually, and their average score was taken as the final result. The chi-square test was used to assess the difference. RESULTS: The coronal e-THRIVE score is 4.60, which is higher than the DCE-THRIVE score of 3.48, there are significant differences between the images obtained by two sequences (P = 1.2712e-8). According to the score of images, 44 patients (84.61%) had high-quality images on the bilateral breast. Only 3 patients' (5.77%) images were not ideal on both sides. The improved method is effective for most patients to get better images. CONCLUSIONS: The proposed coronal e-THRIVE scan can get higher quality reconstruction images than the conventional method to visualize the course of arteries and the distribution of lymph nodes in most patients, which will be helpful for the clinical follow-up treatment.

5.
Biomed Mater ; 16(4)2021 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-34098538

RESUMO

In this study, the silk fibroin/nano-hydroxyapatite/hyaluronic acid (SF/nHAp/HA) composite scaffolds with different HA contents were developed by blending, cross-linking and freeze-drying, and their physicochemical properties and cell biocompatibilityin vitrowere subsequently studied. It was observed that the molecular conformation of the composite scaffolds was mainly composed of silk I and a small amount of theß-sheets structure. On enhancing the HA content, the pore size of the scaffold decreased, while the porosity, water absorption, swelling ratio and mechanical properties were observed to increase. In particular, the SF/nHAp/HA scaffold with a 5.0 wt% ratio exhibited the highest water absorption and mechanical properties among the developed materials. In addition, thein vitrocytocompatibility analysis showed that the bone marrow mesenchymal stem cells exhibited excellent cell proliferation and osteogenic differentiation ability on the SF/nHAp/5.0 wt%HA scaffolds, as compared with the other scaffolds. It can be concluded that the developed composite scaffolds represent a promising class of materials for the bone tissue repair and regeneration.

6.
Quant Imaging Med Surg ; 11(6): 2354-2375, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34079707

RESUMO

Background: Predicting the mutation statuses of 2 essential pathogenic genes [epidermal growth factor receptor (EGFR) and Kirsten rat sarcoma (KRAS)] in non-small cell lung cancer (NSCLC) based on CT is valuable for targeted therapy because it is a non-invasive and less costly method. Although deep learning technology has realized substantial computer vision achievements, CT imaging being used to predict gene mutations remains challenging due to small dataset limitations. Methods: We propose a multi-channel and multi-task deep learning (MMDL) model for the simultaneous prediction of EGFR and KRAS mutation statuses based on CT images. First, we decomposed each 3D lung nodule into 9 views. Then, we used the pre-trained inception-attention-resnet model for each view to learn the features of the nodules. By combining 9 inception-attention-resnet models to predict the types of gene mutations in lung nodules, the models were adaptively weighted, and the proposed MMDL model could be trained end-to-end. The MMDL model utilized multiple channels to characterize the nodule more comprehensively and integrate patient personal information into our learning process. Results: We trained the proposed MMDL model using a dataset of 363 patients collected by our partner hospital and conducted a multi-center validation on 162 patients in The Cancer Imaging Archive (TCIA) public dataset. The accuracies for the prediction of EGFR and KRAS mutations were, respectively, 79.43% and 72.25% in the training dataset and 75.06% and 69.64% in the validation dataset. Conclusions: The experimental results demonstrated that the proposed MMDL model outperformed the latest methods in predicting EGFR and KRAS mutations in NSCLC.

7.
Front Cell Dev Biol ; 9: 583572, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33614637

RESUMO

Anthracyclines resistance is commonly seen in patients with estrogen receptor α (ERα) positive breast cancer. Epithelial-mesenchymal transition (EMT), which is characterized with the loss of epithelial cell polarity, cell adhesion and acquisition of new invasive property, is considered as one of the mechanisms of chemotherapy-induced drug resistance. In order to identify factors that associated with doxorubicin resistance, we performed in vitro and in vivo experiments using human and mouse breast cancer cell lines with different ERα status. Cell survival experiments revealed that ERα-positive cells (MCF-7 and MCF-7/ADR cell lines), were less sensitive to doxorubicin than ERα-negative (MDA-MB-231, MDA-MB-468) cells, and mouse mammary carcinoma cells (4T-1). The expression of E-cadherin reduced in low-invasive ERα-positive MCF-7 cells after treatment with doxorubicin, indicating epithelial mesenchymal transition. In contrast, the expression of E-cadherin was upregulated in high-invasive ERα-negative cells, showing mesenchymal-epithelial transition (MET). Moreover, it was found that the growth inhibition of 4T-1 cells by doxorubicin was positively correlated with the expression of E-cadherin. In a mouse breast cancer xenograft model, E-cadherin was overexpressed in the primary tumor tissues of the doxorubicin-treated mice. In ERα-positive MCF-7 cells, doxorubicin treatment upregulated the expression of EMT-related transcription factors Snail and Twist, that regulate the expression of E-cadherin. Following overexpression of ERα in ERα-negative cells (MDA-MB-231 and MDA-MB-468), doxorubicin enhanced the upregulation of Snail and Twist, decreased expression of E-cadherin, and decreased the sensitivity of cells to doxorubicin. In contrast, inhibition of ERα activity increased the sensitivity to doxorubicin in ERα-positive MCF-7 cells. These data suggest that the regulation of Snail and/or Twist varies depends on different ERα status. Therefore, doxorubicin combined with anti-estrogen receptor α therapy could improve the treatment efficacy of doxorubicin in ERα-positive breast cancer.

8.
Angew Chem Int Ed Engl ; 60(15): 8251-8257, 2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33511680

RESUMO

Controlling sophisticated motion by molecular motors is a major goal on the road to future actuators and soft robotics. Taking inspiration from biological motility and mechanical functions common to artificial machines, responsive small molecules have been used to achieve macroscopic effects, however, translating molecular movement along length scales to precisely defined linear, twisting and rotary motions remain particularly challenging. Here, we present the design, synthesis and functioning of liquid-crystal network (LCN) materials with intrinsic rotary motors that allow the conversion of light energy into reversible helical motion. In this responsive system the photochemical-driven molecular motor has a dual function operating both as chiral dopant and unidirectional rotor amplifying molecular motion into a controlled and reversible left- or right-handed macroscopic twisting movement. By exploiting the dynamic chirality, directionality of motion and shape change of a single motor embedded in an LC-network, complex mechanical motions including bending, walking and helical motion, in soft polymer materials are achieved which offers fascinating opportunities toward inherently photo-responsive materials.

9.
Artigo em Chinês | MEDLINE | ID: mdl-33254302

RESUMO

Objective:To analyze the imaging features of parapharyngeal space tumors, and to guide the choice of treatment. Method:A retrospective analysis of 75 cases' clinical data of parapharyngeal space tumor was carried out. All patients underwent enhanced CT and/or enhanced MRI, those tumors closely related to blood vessels and vascular tumors were examined by CTA or MRA, those closely related to peripheral nerves were examined by MRN. We evaluated the relationship between tumor and carotid sheath, parotid gland, skull base and hard palate. We choose the treatment according to the imaging features. Result:Imaging revealed 69 benign tumors and 6 malignant tumors. 8 benign tumors chose to follow up, 61 benign tumors and 6 malignant tumors underwent surgery. Among them, 17 cases of tumors were operated by the transoral approach assisted by endoscope, which were located in the medial of carotid sheath, with the main body protruding toward the oropharynx, below the level of the hard palate, and more than 5 mm away from the skull base; 31 cases were resected by the transcervical approach, and the tumor body protruded toward the neck(15 cases were lateral of the carotid sheath, and 16 cases were medial); 16 cases were resected by the transparotid approach, and the tumor harbored a broad interconnecting margin with the parotid gland; there were 3 cases of other approaches(1 case of transnasal approach, 1 case of combined transnasal and transcervical approach, and 1 case of combined transauricular-cervical approach). Postoperative complications occurred in 25 patients, including 9 cases of facial paralysis(6 cases of grade Ⅱ, 2 cases of grade Ⅲ, 1 case of grade Ⅳ), 1 case of facial numbness, 5 cases of Hornor's syndrome; tongue extension deflection in 3 cases, 2 cases cough while drinking water, 1 case of postoperative hematoma formation, 1 case of oral errhysis, hearing loss in 1 case, shoulder shrugging and hand lifting weakness in 1 case, salivary fistula in 1 case, tracheotomy was performed in 1 case because of postoperative oropharyngeal swelling, swallowing obstruction in 1 case, gustatory sweating syndrome in 1 case and acute cerebral infarction was caused by thrombus detachment in 1 case. Conclusion:Imaging results are important basis for the treatment of parapharyngeal space tumors. The choice of surgical approach should be made based on imaging, including the relationship with the big vessels of the neck, the parotid gland, the hard palate, and the distance from the skull base, combined with the nature of the tumor.


Assuntos
Neoplasias , Espaço Parafaríngeo , Humanos , Pescoço , Estudos Retrospectivos , Síndrome
10.
Am J Pathol ; 190(8): 1691-1700, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32360568

RESUMO

The pathologic diagnosis of nasopharyngeal carcinoma (NPC) by different pathologists is often inefficient and inconsistent. We have therefore introduced a deep learning algorithm into this process and compared the performance of the model with that of three pathologists with different levels of experience to demonstrate its clinical value. In this retrospective study, a total of 1970 whole slide images of 731 cases were collected and divided into training, validation, and testing sets. Inception-v3, which is a state-of-the-art convolutional neural network, was trained to classify images into three categories: chronic nasopharyngeal inflammation, lymphoid hyperplasia, and NPC. The mean area under the curve (AUC) of the deep learning model is 0.936 based on the testing set, and its AUCs for the three image categories are 0.905, 0.972, and 0.930, respectively. In the comparison with the three pathologists, the model outperforms the junior and intermediate pathologists, and has only a slightly lower performance than the senior pathologist when considered in terms of accuracy, specificity, sensitivity, AUC, and consistency. To our knowledge, this is the first study about the application of deep learning to NPC pathologic diagnosis. In clinical practice, the deep learning model can potentially assist pathologists by providing a second opinion on their NPC diagnoses.


Assuntos
Aprendizado Profundo , Diagnóstico por Computador , Carcinoma Nasofaríngeo/diagnóstico , Neoplasias Nasofaríngeas/diagnóstico , Bases de Dados Factuais , Humanos , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/patologia , Redes Neurais de Computação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
11.
Chempluschem ; 85(6): 1104-1110, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32133756

RESUMO

Chiral supramolecular assemblies are abundant in nature, but controlling the chirality of artificial systems still remains a challenge. In this work, we developed a system where supramolecular chirality can be controlled between chiral and achiral states, namely a chiral "1/0" switch using a flower-like azobenzene compound with a binaphthol core. Upon photoisomerization by ultraviolet irradiation, the terminal alkyl tails envelop the chiral "centre" with a reduction in the dihedral angle of the binaphthol moiety from 76.1° to 61.4°, like "closing petals". In the doped liquid crystal E7 matrix, this hierarchical conformational transition prevents the transfer of chirality to the host liquid crystal, resulting in a degradation from cholesteric phase (HTP value: 13.84 µm-1 ) to an achiral nematic phase.

12.
ACS Appl Mater Interfaces ; 12(3): 4052-4060, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31885247

RESUMO

Polymeric nanovehicles have been widely applied in many fields, but during the process of preparation, it is still hard to reach the balance between precise structure control and mass production. In the present work, using industrial pixel grids as the macroscopic template, we applied dual effects of confinement and dielectric difference to speed up the self-assembly of polymeric nanovehicles, even to regulate the generated mesostructures and cargo loading. Within 2 min, a poly(ethylene glycol)-block-poly(d,l-lactide acid) (PEG-b-PDLLA) amphiphilic block copolymer layer was rapidly pushed off and broken down into uniform nanoparticles at 40 V. Hereinto, increasing volume of the outer aqueous phase in pixel grids favored the architectonic transformation of the generated nanovehicles from solid micelles with a diameter of 95 nm to hollow vesicles with a diameter of 232 nm. In particular, all the elements from the confinement cells to the preparation process can be completed via wet printing. Electric-field-induced pixel template technology is facile, cheap, controllable, and recyclable, and it is anticipated to promote continuous and bulk production of polymeric nanovehicles.

13.
Chemosphere ; 243: 125317, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31722262

RESUMO

Metallurgical microbial electrosynthesis systems (MES) are holding great promise for simultaneous heavy metal removal and acetate production from heavy metal-contaminated and organics-barren waters. How critical parameters of strain of electrotroph, cathode potential and initial heavy metal concentration affect MES performance, however, is not yet fully understood. Heavy metal of Cu(II) and four Cu(II)-tolerant electrotrophs (Stenotrophomonas maltophilia JY1, Citrobacter sp. JY3, Pseudomonas aeruginosa JY5 and Stenotrophomonas sp. JY6) were employed to evaluate MES performance at various cathode potentials (-900 or -600 mV vs. standard hydrogen electrode) and initial Cu(II) concentrations (60-120 mg L-1). Each electrotrophs exhibited incremental Cu(II) removals with increased Cu(II) at -900 mV, higher than at -600 mV or in the abiotic controls. Acetate production by JY1 and JY6 decreased with the increase in initial Cu(II), compared to an initial increase and a decrease thereafter for JY3 and JY5. For each electrotrophs, the biofilms than the planktonic cells released more amounts of extracellular polymeric substances (EPS) with a compositional diversity and stronger Cu(II) complexation at -900 mV. These were higher than at -600 mV, or in the controls either under open circuit conditions or in the absence of Cu(II). This work demonstrates the interdependence of strain of electrotroph, cathode potential and initial Cu(II) on simultaneous Cu(II) removal and acetate production through the release of different amounts of EPS with diverse composites, contributing to enhancing the controlled MES for efficient recovery of value-added products from Cu(II)-contaminated and organics-barren waters.


Assuntos
Cobre/química , Modelos Químicos , Poluentes Químicos da Água/química , Acetatos , Biofilmes , Cobre/análise , Eletrodos , Plâncton , Poluentes Químicos da Água/análise , Purificação da Água/métodos
14.
Polymers (Basel) ; 10(10)2018 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-30961044

RESUMO

Electrowetting-on-dielectric is a preferred option in practical applications of the electrowetting phenomenon but limited by dielectric and breakdown performances of the dielectric layer. In the present work, a ceramic/polymer nanocomposite as a novel dielectric layer is developed to intensify the overall electrowetting performances by multiscale interface effect. Hereinto, surface fluoro-modified ZrO2 nanoparticles (mZrO2) are dispersed well in AF 1600 matrix to form a mZrO2@AF 1600 nanocomposite. The small addition of mZrO2 improves the dielectric constant of the nanocomposite, and the experimental value is larger than the theoretical value calculated by Maxwell⁻Garnett model, but fits well with the Rahaman⁻Khastgir model. The molecular dynamics simulations with the explicit model further verify the interfacial effect. Meanwhile, double contact angle modulation and higher breakdown field strength (Eb) are obtained. For the three-layer sandwich structure, both the top and bottom AF 1600 layer decrease the surface roughness for better electrowetting reproducibility and wider wettability modulation. The Forlani⁻Minnaja theory related to the empirical relationship between Eb and thickness of dielectric layer fit well with the monolayer structure, but cannot be applied in multi-layer structures. A new relationship is proposed to guide the design of dielectric multi-layers with high breakdown field strength.

15.
Polymers (Basel) ; 9(6)2017 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-30970896

RESUMO

In electrowetting devices, hydrophobic insulating layer, namely dielectric layer, is capable of reversibly switching surface wettability through applied electric field. It is critically important but limited by material defects in dielectricity, reversibility, film forming, adhesiveness, price and so on. To solve this key problem, we introduced a novel fluorinated polyacrylate-poly(1H,1H,2H,2H-perfluoroctylmethacrylate (PFMA) to construct micron/submicron-scale dielectric layer via facile spray coating of nanoemulsion for replacing the most common Teflon AF series. All the results illustrated that, continuous and dense PFMA film with surface relief less than 20 nm was one-step fabricated at 110 °C, and exhibited much higher static water contact angle of 124°, contact angle variation of 42°, dielectric constant of about 2.6, and breakdown voltage of 210 V than Teflon AF 1600. Particularly, soft and highly compatible polyacrylate mainchain assigned five times much better adhesiveness than common adhesive tape, to PFMA layer. As a promising option, PFMA dielectric layer may further facilitate tremendous development of electrowetting performances and applications.

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