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1.
IEEE Trans Med Imaging ; 43(3): 1180-1190, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37917514

RESUMO

Accurate and automatic detection of pelvic lymph nodes in computed tomography (CT) scans is critical for diagnosing lymph node metastasis in colorectal cancer, which in turn plays a crucial role in its staging, treatment planning, surgical guidance, and postoperative follow-up of colorectal cancer. However, achieving high detection sensitivity and specificity poses a challenge due to the small and variable sizes of these nodes, as well as the presence of numerous similar signals within the complex pelvic CT image. To tackle these issues, we propose a 3D feature-aware online-tuning network (FAOT-Net) that introduces a novel 1.5-stage structure to seamlessly integrate detection and refinement via our online candidate tuning process and takes advantage of multi-level information through the tailored feature flow. Furthermore, we redesign the anchor fitting and anchor matching strategies to further improve detection performance in a nearly hyperparameter-free manner. Our framework achieves the FROC score of 52.8 and the sensitivity of 91.7% with 16 false positives per scan on the PLNDataset. Code will be available at: github.com/SCUsomebody/FAOT-Net/.


Assuntos
Neoplasias Colorretais , Linfonodos , Humanos , Estadiamento de Neoplasias , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Tomografia Computadorizada por Raios X/métodos , Pelve/diagnóstico por imagem
2.
Quant Imaging Med Surg ; 13(9): 5483-5501, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37711811

RESUMO

Background: Abdominal lymph node partition is highly relevant to colorectal cancer (CRC) metastasis, which may further affect patient prognosis and survival quality. In the traditional diagnostic process, medical radiologists must partition all lymph nodes from the computed tomography (CT) images for further diagnostics. The manual interpretation of abdominal nodes is experience-dependent and time-consuming, especially for node partition. Therefore, automated partition methods are desirable to make the diagnostic process more accessible. Automatic abdominal lymph node partition is a challenging task due to the subtle morphological features of the nodes and the complex relative position information of the abdominal structure. Methods: In this paper, a node-oriented dataset containing 6,880 nodes with partition labels was constructed by seasoned professionals through 2-round annotation due to there being no dataset with node-oriented labels to perform the partition task. In addition, specific masking strategies and attention mechanisms were proposed for the primary deep neural networks (DNNs). The specific masking strategy could utilize the positional and morphological information more substantially, which intensively exploits prior knowledge and hones the relative positional information in the lower abdomen. The comprehensive attention mechanism could introduce direction-aware information to enhance the inter-channel relationship of features and capture rich contextual relationships with multi-scale kernels. Results: The experiments were based on the node-oriented dataset. The proposed method achieved superior performance [accuracy (ACC): 89.74%; F1 score (F1): 85.95%; area under the curve (AUC): 88.23%], which is significantly higher than the baseline model with several masking strategies (ACC: 62.05-86.16%; F1: 51.77-80.86%; AUC: 60.44-83.94%). For exploration of attention, the proposed method also outperformed the state-of-the-art convolutional block attention module (CBAM; ACC: 88.90%; F1: 84.09%; AUC: 86.86%) with the same proposed input form. Conclusions: Experimental results indicate that the innovative method performs better in experimental metrics than other prevalent methods. The proposed method is expected to be introduced in future medical scenarios, which will help doctors to optimize the diagnosis workflow and improve partition sensitivity.

3.
Quant Imaging Med Surg ; 13(1): 49-57, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36620168

RESUMO

Background: To describe grayscale ultrasound (US) features of metastatic ovarian tumors (MOTs) based on origin of the primary tumor in a large sample size study. Methods: This retrospective cross-sectional single-center study included 112 patients with 190 histopathologically confirmed MOTs. Among the patients, 102 collectively had 144 masses, which were detected via US. The clinical data and static US images of MOTs were collected. Results: The MOTs were mostly bilateral (78.9%) but had a lower rate of bilaterality when detected by US (55.6%). Breast cancer metastasis had the highest nondetection rate (69.6%), because its focal metastasis could only be recognized using histology or immunohistochemistry. The stomach was the most common origin of metastasis (45.3% and 50.7% detected via pathology and US, respectively). The US images were classified into three subtypes: multilocular solid (Type A), purely solid (Type B), and solid with several round or oval cysts (Type C). The MOTs that originated from the colon mostly belonged to Type A (65.1%) and closely mimicked primary epithelial ovarian tumor morphologically. The MOTs that originated from the stomach predominantly belonged to Types B (31.5%) and C (57.5%). Signet-ring cell carcinoma (SRCC) corresponded to Types B and C regardless of origin. Conclusions: The developed novel typing method provides more vivid images for classifying MOTs compared with existing typing methods. Given that no specific sonographic parameters have been established to distinguish MOTs from primary invasive ovarian tumors, these images may be helpful in diagnosing these masses.

4.
J Gastric Cancer ; 22(4): 369-380, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36316111

RESUMO

PURPOSE: Tumor recurrence is the principal cause of poor outcomes in remnant gastric cancer (RGC) after resection. We sought to elucidate the recurrent patterns according to tumor locations in RGC. MATERIALS AND METHODS: Data were collected from the Shanghai Cancer Center between January 2006 and December 2020. A total of 129 patients with RGC were included in this study, of whom 62 had carcinomas at the anastomotic site (group A) and 67 at the non-anastomotic site (group N). The clinicopathological characteristics, surgical results, recurrent diseases, and survival were investigated according to tumor location. RESULTS: The time interval from the previous gastrectomy to the current diagnosis was 32.0±13.0 and 21.0±13.4 years in groups A and N, respectively. The previous disease was benign in 51/62 cases (82.3%) in group A and 37/67 cases (55.2%) in group N (P=0.002). Thirty-three patients had documented sites of tumor recurrence through imaging or pathological examinations. The median time to recurrence was 11.0 months (range, 1.0-35.1 months). Peritoneal recurrence occurred in 11.3% (7/62) of the patients in group A versus 1.5% (1/67) of the patients in group N (P=0.006). Hepatic recurrence occurred in 3.2% (2/62) of the patients in group A versus 13.4% (9/67) of the patients in group N (P=0.038). Patients in group A had significantly better overall survival than those in group N (P=0.046). CONCLUSIONS: The tumor location of RGC is an essential factor for predicting recurrence patterns and overall survival. When selecting an optimal postoperative follow-up program for RGC, physicians should consider recurrent features according to the tumor location.

5.
Am J Cancer Res ; 12(8): 3713-3728, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36119818

RESUMO

This study was conducted to investigate the prognostic significance of a combination of fibrinogen and neutrophil-to-lymphocyte ratio (NLR) named the F-NLR score as a novel indicator and further create nomograms for predicting the prognosis of patients with renal cell carcinoma (RCC) treated with laparoscopic nephrectomy. A total of 425 patients with RCC who underwent laparoscopic nephrectomy were included in this study. Then, we divided the patients based on the cut-off values of their F-NLR score into three categories: F-NLR 2 (both high fibrinogen and NLR), F-NLR 0 (both low fibrinogen and NLR), and F-NLR 1 (remaining patients). Cox regression analysis was performed to investigate the predictive performance of the F-NLR score on overall survival (OS) and cancer-specific survival (CSS). Predictive nomograms of F-NLR were established and internally validated. Time-dependent receiver operating characteristic (ROC) curve analysis was performed to assess the predictive accuracy of the nomogram, NLR, and fibrinogen as prognostic markers. The F-NLR 0, 1, and 2 groups included 226 (53.2%), 147 (34.6%), and 52 (12.2%) patients, respectively. Cox regression analysis showed that a high F-NLR score was significantly associated with poor prognosis and acted as an independent prognostic factor for OS and CSS (all P < 0.05). Predictive nomograms with F-NLR for OS (C-index: 0.773) and CSS (C-index: 0.838) were well developed. Time-dependent ROC results showed that nomograms containing F-NLR had better predictive performance than NLR and fibrinogen. F-NLR score was a novel effective prognostic biomarker for patients with RCC undergoing laparoscopic nephrectomy.

6.
Quant Imaging Med Surg ; 12(7): 3833-3843, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35782244

RESUMO

Background: The high false-positive rates of US Breast Imaging Reporting and Data System (BI-RADS) category 3-4a breast lesions leads to excessive biopsies of many benign lesions, and our aim was to investigate the diagnostic performance achieved by adding a maximum elasticity (Emax) of shear-wave elastography (SWE) to ultrasound (US) to evaluate US BI-RADS category 3-4a breast lesions using conservative and aggressive approaches. We explored the capacity of using this method to avoid unnecessary biopsies without increasing the probability of missing breast cancers. Methods: A total of 123 breast lesions of 120 patients classified as BI-RADS category 3 or 4a were enrolled from January 2019 to December 2019. The US features were evaluated according to the US BI-RADS lexicon. The maximum diameter measured on the US was defined as the size of the lesion. The Emax was assessed by SWE, and the average Emax of breast lesions on two images were calculated and recorded as the final maximum Young's modulus. The diagnostic performance of the combined B-mode US and SWE approach for BI-RADS category 3-4a breast lesions was tested using a conservative approach and an aggressive approach. In the conservative approach, the lesions were downgraded with Emax of 30 kPa or less and upgraded with Emax of 160 kPa or more. In the aggressive approach, the lesions were downgraded with Emax of 80 kPa or less and upgraded with Emax of 160 kPa or more. Pathologic results were defined as the reference standard. Results: Among all 123 breast lesions, there were 60 lesions classified as BI-RADS category 3 and 63 lesions classified as BI-RADS category 4a. Compared to the B-mode US, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy, and area under the receiver operating characteristic (ROC) curve (AUC) of the combined B-mode US and SWE with a conservative approach changed from 88.9% to 94.4%, 55.2% to 60.0%, 25.4% to 28.8%, 96.7% to 98.4%, 60.2% to 65.0%, and 0.721 to 0.772, respectively. The specificity, PPV, and accuracy of combined B-mode US and SWE with an aggressive approach increased from 55.2% to 72.4%, 25.4% to 29.3%, and 60.2% to 71.5%, respectively, but this was accompanied with decreases in the sensitivity from 88.9% to 66.7%, the NPV from 96.7% to 92.7%, and the AUC from 0.721 to 0.695. Conclusions: The addition of SWE improves the diagnostic performance of breast US. Adding the diagnostic criteria of SWE to the BI-RADS assessment of B-mode US, downgrading the lesions with Emax 30 kPa or less, and upgrading the lesions with Emax 160 kPa or more helped discriminate low suspicion lesions from benign lesions in order to decrease false-positive findings and avoid missing cancer diagnosis.

7.
Sci Rep ; 12(1): 5167, 2022 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-35338176

RESUMO

The detection and characterization of lymph nodes through interpreting abdominal medical images are significant for diagnosing and treating colorectal cancer recurrence. However, interpreting abdominal medical images manually is labor-intensive and time-consuming. The related radiology education has many limitations as well. In this context, we seek to build an extensive collection of abdominal medical images with ground truth labels for lymph nodes recognition research and help junior doctors to train their interpretation skills. Therefore, we develop TeachMe, which is a web-based teaching system for annotating abdominal lymph nodes. The system has a three-level annotation-review workflow to construct an expert database of abdominal lymph nodes and a feedback mechanism helping junior doctors to learn the tricks of interpreting abdominal medical images. TeachMe's functionalities make itself stand out against other platforms. To validate these functionalities, we invite a medical team from Gastrointestinal Surgery Center, West China Hospital, to participate in the data collection workflow and experience the feedback mechanism. With the help of TeachMe, an expert dataset of abdominal lymph nodes has been created and an automated detection model for abdominal lymph nodes with incredible performances has been proposed. Moreover, through three rounds of practicing via TeachMe, our junior doctors' interpretation skills have been improved.


Assuntos
Linfonodos , Radiologia , Humanos , Internet , Aprendizagem , Corpo Clínico Hospitalar
8.
IEEE Trans Med Imaging ; 41(7): 1849-1861, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35120001

RESUMO

Lesion volume segmentation in medical imaging is an effective tool for assessing lesion/tumor sizes and monitoring changes in growth. Since manually segmentation of lesion volume is not only time-consuming but also requires radiological experience, current practices rely on an imprecise surrogate called response evaluation criteria in solid tumors (RECIST). Although RECIST measurement is coarse compared with voxel-level annotation, it can reflect the lesion's location, length, and width, resulting in a possibility of segmenting lesion volume directly via RECIST measurement. In this study, a novel weakly-supervised method called RECISTSup is proposed to automatically segment lesion volume via RECIST measurement. Based on RECIST measurement, a new RECIST measurement propagation algorithm is proposed to generate pseudo masks, which are then used to train the segmentation networks. Due to the spatial prior knowledge provided by RECIST measurement, two new losses are also designed to make full use of it. In addition, the automatically segmented lesion results are used to supervise the model training iteratively for further improving segmentation performance. A series of experiments are carried out on three datasets to evaluate the proposed method, including ablation experiments, comparison of various methods, annotation cost analyses, visualization of results. Experimental results show that the proposed RECISTSup achieves the state-of-the-art result compared with other weakly-supervised methods. The results also demonstrate that RECIST measurement can produce similar performance to voxel-level annotation while significantly saving the annotation cost.


Assuntos
Algoritmos , Processamento de Imagem Assistida por Computador , Processamento de Imagem Assistida por Computador/métodos , Radiografia , Critérios de Avaliação de Resposta em Tumores Sólidos
9.
Bioconjug Chem ; 33(6): 1035-1048, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34784710

RESUMO

Ultrasound-activated therapies have been regarded as the efficient strategy for tumor treatment, among which sonosensitizer-enabled sonodynamic oxidative tumor therapy features intrinsic advantages as compared to other exogenous trigger-activated dynamic therapies. Nanomedicine-based nanosonosensitizer design has been extensively explored for improving the therapeutic efficacy of sonodynamic therapy (SDT) of tumor. This review focuses on solving two specific issues, i.e., precise and enhanced sonodynamic oxidative tumor treatment, by rationally designing and engineering multifunctional composite nanosonosensitizers. This multifunctional design can augment the therapeutic efficacy of SDT against tumor by either improving the production of reactive oxygen species or inducing the synergistic effect of SDT-based combinatorial therapies. Especially, this multifunctional design is also capable of endowing the nanosonosensitizer with bioimaging functionality, which can effectively guide and monitor the therapeutic procedure of the introduced sonodynamic oxidative tumor treatment. The design principles, underlying material chemistry for constructing multifunctional composite nanosonosensitizers, intrinsic synergistic mechanism, and bioimaging guided/monitored precise SDT are summarized and discussed in detail with the most representative paradigms. Finally, the existing critical issues, available challenges, and potential future developments of this research area are also discussed for promoting the further clinical translations of these multifunctional composite nanosonosensitizers in SDT-based tumor treatment.


Assuntos
Nanopartículas , Terapia por Ultrassom , Linhagem Celular Tumoral , Nanomedicina , Estresse Oxidativo , Espécies Reativas de Oxigênio , Terapia por Ultrassom/métodos
11.
J Nanobiotechnology ; 19(1): 290, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34579711

RESUMO

BACKGROUND: In comparison with traditional therapeutics, it is highly preferable to develop a combinatorial therapeutic modality for nanomedicine and photothermal hyperthermia to achieve safe, efficient, and localized delivery of chemotherapeutic drugs into tumor tissues and exert tumor-activated nanotherapy. Biocompatible organic-inorganic hybrid hollow mesoporous organosilica nanoparticles (HMONs) have shown high performance in molecular imaging and drug delivery as compared to other inorganic nanosystems. Disulfiram (DSF), an alcohol-abuse drug, can act as a chemotherapeutic agent according to its recently reported effectiveness for cancer chemotherapy, whose activity strongly depends on copper ions. RESULTS: In this work, a therapeutic construction with high biosafety and efficiency was proposed and developed for synergistic tumor-activated and photothermal-augmented chemotherapy in breast tumor eradication both in vitro and in vivo. The proposed strategy is based on the employment of HMONs to integrate ultrasmall photothermal CuS particles onto the surface of the organosilica and the molecular drug DSF inside the mesopores and hollow interior. The ultrasmall CuS acted as both photothermal agent under near-infrared (NIR) irradiation for photonic tumor hyperthermia and Cu2+ self-supplier in an acidic tumor microenvironment to activate the nontoxic DSF drug into a highly toxic diethyldithiocarbamate (DTC)-copper complex for enhanced DSF chemotherapy, which effectively achieved a remarkable synergistic in-situ anticancer outcome with minimal side effects. CONCLUSION: This work provides a representative paradigm on the engineering of combinatorial therapeutic nanomedicine with both exogenous response for photonic tumor ablation and endogenous tumor microenvironment-responsive in-situ toxicity activation of a molecular drug (DSF) for augmented tumor chemotherapy.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Tratamento Farmacológico/métodos , Nanomedicina , Nanopartículas/uso terapêutico , Terapia Fototérmica/métodos , Animais , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Cobre , Dissulfiram/farmacologia , Ditiocarb , Feminino , Camundongos Endogâmicos BALB C , Camundongos Nus , Tamanho da Partícula , Fototerapia , Microambiente Tumoral/efeitos dos fármacos
12.
Microb Pathog ; 141: 103960, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31953224

RESUMO

BACKGROUND: Mycoplasma pneumoniae (MP) is a common cause of community-acquired pneumonia (CAP) among the children and adults that results upper and lower respiratory tract infections. OBJECTIVE: This study was aimed to inspect the ameliorative action of A. chinensis synthesized ZnONPs against M. pneumoniae infected pneumonia mice model. MATERIALS AND METHODS: ZnO NPs was synthesized from Albizia chinensis bark extract and characterized by UV-Vis spectroscopy, Fourier Transform Infrared (FTIR), Transmission Electron Microscopy (TEM), energy dispersive X-ray (EDX) and atomic force microscope (AFM) analyses. The antibacterial effectual of synthesized ZnONPs were examined against clinical pathogens. The pneumonia was induced to BALB/c mice via injecting the M. pneumoniae and treated with synthesized ZnONPs, followed by the total protein content, total cell counts and inflammatory mediators level was assessed in the BALF of experimental animals. The Histopathological investigation was done in the lung tissues of test animals. RESULTS: The outcomes of this work revealed that the formulated ZnONPs was quasi-spherical, radial and cylindrical; the size was identified as 116.5 ± 27.45 nm in diameter. The in vitro antimicrobial potential of formulated ZnO-NPs displayed noticeable inhibitory capacity against the tested fungal and bacterial strains. The administration of synthesized ZnO-NPs in MP infected mice model has significantly reduced the levels of total protein, inflammatory cells, inflammatory cytokines such as IL-1, IL-6, IL-8, tumour necrosis factor-alpha (TNF-a) and transforming growth factor (TGF). Besides, the histopathological examination of MP infected mice lung tissue showed the cellular arrangements were effectively retained after administration of synthesized ZnO-NPs. CONCLUSION: In conclusion, synthesized ZnO-NPs alleviate pneumonia progression via reducing the level of inflammatory cytokines and inflammatory cells in MP infected mice model.


Assuntos
Albizzia/química , Antibacterianos/síntese química , Antibacterianos/farmacologia , Nanopartículas Metálicas/química , Mycoplasma pneumoniae/efeitos dos fármacos , Extratos Vegetais/química , Óxido de Zinco/química , Animais , Antibacterianos/química , Anti-Infecciosos/síntese química , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Citocinas/metabolismo , Fungos/efeitos dos fármacos , Mediadores da Inflamação , Nanopartículas Metálicas/uso terapêutico , Camundongos , Testes de Sensibilidade Microbiana , Pneumonia por Mycoplasma/microbiologia , Pneumonia por Mycoplasma/patologia , Análise Espectral
13.
Breastfeed Med ; 14(10): 712-717, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31539269

RESUMO

Background and Objectives: The breast undergoes extensive physiologic changes during pregnancy/lactation. We aimed to review the ultrasound (US) imaging characteristics of breast lesions during pregnancy/lactation and to demonstrate ultrasonography as an excellent imaging modality in this patient population. Materials and Methods: We performed a retrospective study involving 195 patients with 206 pathologically confirmed breast lesions during pregnancy/lactation over the period of January 2010 to December 2018; 51 were diagnosed with breast cancer, including 50 invasive ductal carcinomas and 1 low malignant potential phyllodes tumor, whereas 144 were diagnosed with 155 benign lesions, including 103 mastitis/abscesses, 45 fibroadenomas, 2 intraductal papillomas, 2 sclerosing lesions, and 3 benign phyllodes tumors. The patients' age, lesion diameter, and US characteristics were analyzed. Results: The breast lesions of patients during pregnancy/lactation were compared with those during nonpregnancy/lactation. Patients with breast cancer or fibroadenomas during pregnancy/lactation were younger than those during nonpregnancy/lactation. The average lesion diameter was significantly higher among pregnant/lactating patients compared with controls of childbearing age for fibroadenomas, but not for malignant lesions. The fibroadenomas and mastitis/abscesses during pregnancy/lactation usually have higher BI-RADS categories than those during nonpregnancy/lactation. Conclusions: The imaging features of breast cancer during pregnancy/lactation did not differ much from those of nonpregnancy/lactation; however, some benign lesions had suspicious sonographic features, and US-guided core biopsies were necessary for differentiating benign from malignant lesions.


Assuntos
Aleitamento Materno/efeitos adversos , Neoplasias da Mama , Mama , Carcinoma Ductal , Fibroadenoma , Mastite , Tumor Filoide , Complicações Neoplásicas na Gravidez/diagnóstico , Ultrassonografia/métodos , Adulto , Fatores Etários , Biópsia com Agulha de Grande Calibre/métodos , Mama/diagnóstico por imagem , Mama/patologia , Neoplasias da Mama/etiologia , Neoplasias da Mama/patologia , Carcinoma Ductal/etiologia , Carcinoma Ductal/patologia , Diagnóstico Diferencial , Feminino , Fibroadenoma/etiologia , Fibroadenoma/patologia , Humanos , Biópsia Guiada por Imagem/métodos , Mastite/etiologia , Mastite/patologia , Tumor Filoide/etiologia , Tumor Filoide/patologia , Gravidez , Estudos Retrospectivos , Carga Tumoral
14.
Small ; 15(31): e1901834, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31207096

RESUMO

Bacterial infection caused by pathogenic bacteria has long been an intractable issue that threatens human health. Herein, the fact that nanocatalysts with single iron atoms anchored in nitrogen-doped amorphous carbon (SAF NCs) can effectively induce peroxidase-like activities in the presence of H2 O2 , generating abundant hydroxyl radicals for highly effective bacterial elimination (e.g., Escherichia coli and Staphylococcus aureus), is reported. In combination with the intrinsic photothermal performance of the nanocatalysts, noticeable bacterial-killing effects are extensively investigated. Especially, the antibacterial mechanism of critical cell membrane destruction induced by SAF NCs is unveiled. Based on the bactericidal properties of SAF NCs, in vivo bacterial infections propagated at wounds by E. coli and S. aureus pathogens can be effectively eradicated, resulting in better wound healing. Collectively, the present study highlights the highly efficient in vitro antibacterial and in vivo anti-infection performances by the single-iron-atom-containing nanocatalysts.


Assuntos
Antibacterianos/farmacologia , Ferro/farmacologia , Nanopartículas/química , Animais , Carbono/química , Catálise , Escherichia coli/efeitos dos fármacos , Escherichia coli/ultraestrutura , Radical Hidroxila/química , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Nanopartículas/ultraestrutura , Nitrogênio/química , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/ultraestrutura
15.
Adv Sci (Weinh) ; 6(3): 1801733, 2019 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-31168441

RESUMO

Emerging nanocatalytic tumor therapies based on nontoxic but catalytically active inorganic nanoparticles (NPs) for intratumoral production of high-toxic reactive oxygen species have inspired great research interest in the scientific community. Nanozymes exhibiting natural enzyme-mimicking catalytic activities have been extensively explored in biomedicine, mostly in biomolecular detection, yet much fewer researches are available on specific nanocatalytic tumor therapy. This study reports on the construction of an efficient biomimetic dual inorganic nanozyme-based nanoplatform, which triggers cascade catalytic reactions for tumor microenvironment responsive nanocatalytic tumor therapy based on ultrasmall Au and Fe3O4 NPs coloaded dendritic mesoporous silica NPs. Au NPs as the unique glucose oxidase-mimic nanozyme specifically catalyze ß-D-glucose oxidation into gluconic acid and H2O2, while the as produced H2O2 is subsequently catalyzed by the peroxidase-mimic Fe3O4 NPs to liberate high-toxic hydroxyl radicals for inducing tumor-cell death by the typical Fenton-based catalytic reaction. Extensive in vitro and in vivo evaluations have demonstrated high nanocatalytic-therapeutic efficacy with a desirable tumor-suppression rate (69.08%) based on these biocompatible composite nanocatalysts. Therefore, this work paves a way for nanocatalytic tumor therapy by rationally designing inorganic nanozymes with multienzymatic activities for achieving high therapeutic efficacy and excellent biosafety simultaneously.

16.
Nat Commun ; 9(1): 4777, 2018 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-30429468

RESUMO

Cell-based drug delivery systems have shown promising capability for tumor-targeted therapy owing to the intrinsic tumor-homing and drug-carrying property of some living cells. However, imaging tracking of their migration and bio-effects is urgently needed for clinical application, especially for glioma. Here, we report the inflammation-activatable engineered neutrophils by internalizing doxorubicin-loaded magnetic mesoporous silica nanoparticles (ND-MMSNs) which can provide the potential for magnetic resonance (MR) imaging tracking of the drug-loaded cells to actively target inflamed brain tumor after surgical resection of primary tumor. The phagocytized D-MMSNs possess high drug loading efficiency and do not affect the host neutrophils' viability, thus remarkably improving intratumoral drug concentration and delaying relapse of surgically treated glioma. Our study offers a new strategy in targeted cancer theranostics through combining the merits of living cells and nanoparticle carriers.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Neoplasias Encefálicas/tratamento farmacológico , Doxorrubicina/administração & dosagem , Portadores de Fármacos , Glioma/tratamento farmacológico , Nanopartículas , Neutrófilos , Animais , Neoplasias Encefálicas/cirurgia , Movimento Celular , Rastreamento de Células , Quimioterapia Adjuvante , Sistemas de Liberação de Medicamentos , Armadilhas Extracelulares , Óxido Ferroso-Férrico , Glioma/cirurgia , Imageamento por Ressonância Magnética , Imãs , Camundongos , Microscopia Eletrônica de Transmissão , Dióxido de Silício
17.
Adv Sci (Weinh) ; 5(4): 1700474, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29721406

RESUMO

The blood brain barrier is the main obstacle to delivering diagnostic and therapeutic agents to the diseased sites of brain. It is still of great challenge for the combined use of focused ultrasound (FUS) and theranostic nanotechnology to achieve noninvasive and localized delivery of chemotherapeutic drugs into orthotopic brain tumor. In this work, a unique theranostic nanoplatform for highly efficient photoacoustic imaging-guided chemotherapy of brain tumor both in vitro and in vivo, which is based on the utilization of hollow mesoporous organosilica nanoparticles (HMONs) to integrate ultrasmall Cu2-x Se particles on the surface and doxorubicin inside the hollow interior, is synthesized. The developed multifunctional theranostic nanosystems exhibit tumor-triggered programmed destruction due to the reducing microenvironment-responsive cleavage of disulfide bonds that are incorporated into the framework of HMONs and linked between HMONs and Cu2-x Se, resulting in tumor-specific biodegradation and on-demand drug-releasing behavior. Such tumor microenvironment-responsive biodegradable and biocompatible theranostic nanosystems in combination with FUS provide a promising delivery nanoplatform with high performance for orthotopic brain tumor imaging and therapy.

18.
Ultrasound Med Biol ; 42(11): 2538-2544, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27554069

RESUMO

Schwannomas are common benign tumors that develop in peripheral nerves. High-resolution ultrasound (HRUS) is an effective imaging modality in clinics. The aim of this study was to define the value of HRUS in diagnosing schwannomas that originate from different nerves in limbs. We reviewed the ultrasound and surgical records of 72 pathologically confirmed schwannomas in the limbs of 60 patients. Results revealed that 44 (61.1%) of 72 cases, 44 (75.9%) of 58 cases and 0 (0%) of 14 cases received an overall correct pre-operative diagnosis, a correct pre-operative diagnosis in nerve trunks and a correct pre-operative diagnosis in small branches, respectively. Identification of the nerve of origin of schwannomas through HRUS likely increased confidence in diagnosing these benign tumors.


Assuntos
Neurilemoma/diagnóstico por imagem , Ultrassonografia/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Extremidades/diagnóstico por imagem , Extremidades/inervação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
19.
Ultrasound Med Biol ; 40(1): 1-10, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24210860

RESUMO

Previous studies have reported the usefulness of diffuse optical tomography (DOT), ultrasound elastography (UE) and mammography in differentiating breast tumors. This study was aimed at evaluating and comparing DOT, UE and mammography with respect to their diagnostic performance in differentiating benign and malignant breast tumors. Of the 67 tumors, 45 were histopathologically benign, and 22 were malignant. UE was the most specific (93.33%) of the three diagnostics modalities. DOT and UE were both more accurate (80.60% and 89.55%, respectively) than mammography (63.08%). UE + mammography (93.33% and 91.04%) and DOT + mammography (77.78% and 82.09%) exhibited higher specificity and accuracy, respectively, than mammography alone (57.78% and 63.08%). Receiver operating characteristic (ROC) curves were constructed to assess the performance of the modalities. In conclusion, UE and DOT were superior to conventional mammography in terms of both specificity and accuracy. DOT and UE improve the specificity and accuracy of breast cancer diagnosis, and combining the two modalities improves the diagnostic value.


Assuntos
Algoritmos , Neoplasias da Mama/diagnóstico , Técnicas de Imagem por Elasticidade/métodos , Interpretação de Imagem Assistida por Computador/métodos , Mamografia/métodos , Tomografia Óptica/métodos , Idoso , Feminino , Humanos , Aumento da Imagem/métodos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
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