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1.
World J Gastroenterol ; 28(22): 2457-2467, 2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35979257

RESUMO

BACKGROUND: A convolutional neural network (CNN) is a deep learning algorithm based on the principle of human brain visual cortex processing and image recognition. AIM: To automatically identify the invasion depth and origin of esophageal lesions based on a CNN. METHODS: A total of 1670 white-light images were used to train and validate the CNN system. The method proposed in this paper included the following two parts: (1) Location module, an object detection network, locating the classified main image feature regions of the image for subsequent classification tasks; and (2) Classification module, a traditional classification CNN, classifying the images cut out by the object detection network. RESULTS: The CNN system proposed in this study achieved an overall accuracy of 82.49%, sensitivity of 80.23%, and specificity of 90.56%. In this study, after follow-up pathology, 726 patients were compared for endoscopic pathology. The misdiagnosis rate of endoscopic diagnosis in the lesion invasion range was approximately 9.5%; 41 patients showed no lesion invasion to the muscularis propria, but 36 of them pathologically showed invasion to the superficial muscularis propria. The patients with invasion of the tunica adventitia were all treated by surgery with an accuracy rate of 100%. For the examination of submucosal lesions, the accuracy of endoscopic ultrasonography (EUS) was approximately 99.3%. Results of this study showed that EUS had a high accuracy rate for the origin of submucosal lesions, whereas the misdiagnosis rate was slightly high in the evaluation of the invasion scope of lesions. Misdiagnosis could be due to different operating and diagnostic levels of endoscopists, unclear ultrasound probes, and unclear lesions. CONCLUSION: This study is the first to recognize esophageal EUS images through deep learning, which can automatically identify the invasion depth and lesion origin of submucosal tumors and classify such tumors, thereby achieving good accuracy. In future studies, this method can provide guidance and help to clinical endoscopists.


Assuntos
Endossonografia , Redes Neurais de Computação , Algoritmos , Endoscopia , Endossonografia/métodos , Humanos
2.
BJR Open ; 3(1): 20210002, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35707755

RESUMO

Objectives: This study examines the practice of the regulation of Standards for Medical Exposure Quality Assurance (SMEQA) in Taiwan based on on-site quality audit for radiation therapy systems from 2016 to 2019. Methods: 81 radiation therapy departments, 141 linacs, 9 γ knife systems, 34 high dose rate brachytherapy systems, 20 Tomotherapys, and 6 Cyberknives were audited yearly. Data collection and analysis for each institute's documents including QA procedure, ion chamber and electrometer calibration reports, and a questionnaire relating to machine type and staffing, were requested first and reviewed by auditors. On-site SMEQA core item measurements, including beam output, beam profile and energy constancy for external beam therapy systems, and the source strength, positioning, and timer accuracy for brachytherapy systems were audited second. More than 300 photon beams and more than 400 electron beams were measured each year. Results: There were approximately 8.9 radiotherapy units per million population, and 1.2 medical physicists per unit in Taiwan. For the output measurements, more than 78 and 75% of the photon beams and electron beams, respectively, from linacs were with deviations within ±1.0%. Photon beams have lower beam quality measurement deviations than electron beams. Including in-plane and cross-plane measurements, more than 90 and 85% photon and electron beams, respectively, were with flatness consistency within 1.0%. All audit measurements were within the SMEQA acceptance criteria. Conclusions: According to SMEQA regulations on-site QA audits were successfully carried out from 2016 to 2019 for all Taiwan radiotherapy units. The measurement results showed high quality machine performance in Taiwan. Advances in knowledge: Dosimetry audits with directly acquired measurement readings have lower uncertainties; allow immediate feedback, discussion, and adjustment in a timely manner. In addition to regulation system establishment and education and training implementation, the machine quality is closely related to machine maintenance implementation.

3.
World J Gastroenterol ; 26(38): 5822-5835, 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-33132637

RESUMO

BACKGROUND: Gastric cancer is one of the most common malignant tumors of the digestive system worldwide, posing a serious danger to human health. Cyclooxygenase (COX)-2 plays an important role in the carcinogenesis and progression of gastric cancer. Acetyl-11-keto-ß-boswellic acid (AKBA) is a promising drug for cancer therapy, but its effects and mechanism of action on human gastric cancer remain unclear. AIM: To evaluate whether the phosphatase and tensin homolog (PTEN)/Akt/COX-2 signaling pathway is involved in the anti-tumor effect of AKBA in gastric cancer. METHODS: Human poorly differentiated BGC823 and moderately differentiated SGC7901 gastric cancer cells were routinely cultured in Roswell Park Memorial Institute 1640 medium supplemented with 10% fetal bovine serum and 1% penicillin/streptomycin. Gastric cancer cell proliferation was determined by methyl thiazolyl tetrazolium colorimetric assay. Apoptosis was measured by flow cytometry. Cell migration was assessed using the wound-healing assay. Expression of Bcl-2, Bax, proliferating cell nuclear antigen, PTEN, p-Akt, and COX-2 were detected by Western blot analysis. A xenograft nude mouse model of human gastric cancer was established to evaluate the anti-cancer effect of AKBA in vivo. RESULTS: AKBA significantly inhibited the proliferation of gastric cancer cells in a dose- and time-dependent manner, inhibited migration in a time-dependent manner, and induced apoptosis in a dose-dependent manner in vitro; it also inhibited tumor growth in vivo. AKBA up-regulated the expression of PTEN and Bax, and down-regulated the expression of proliferating cell nuclear antigen, Bcl-2, p-Akt, and COX-2 in a dose-dependent manner. The PTEN inhibitor bpv (Hopic) reversed the high expression of PTEN and low expression of p-Akt and COX-2 that were induced by AKBA. The Akt inhibitor MK2206 combined with AKBA down- regulated the expression of p-Akt and COX-2, and the combined effect was better than that of AKBA alone. CONCLUSION: AKBA inhibits the proliferation and migration and promotes the apoptosis of gastric cancer cells through the PTEN/Akt/COX-2 signaling pathway.


Assuntos
Neoplasias Gástricas , Triterpenos , Animais , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Ciclo-Oxigenase 2 , Humanos , Camundongos , Camundongos Nus , PTEN Fosfo-Hidrolase , Monoéster Fosfórico Hidrolases , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Neoplasias Gástricas/tratamento farmacológico , Tensinas , Triterpenos/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Biosci Rep ; 40(5)2020 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-32364228

RESUMO

OBJECTIVE: The present study is designed to evaluate the anti-tumor effects of myrrh on human gastric cancer both in vitro and in vivo. METHODS: The gastric cancer cell proliferation was determined by MTT assay. Apoptosis was measured by flow cytometry and Hoechst 33342 staining. Wound healing was performed to evaluate the effects of myrrh on the migration. COX-2, PCNA, Bcl-2, and Bax expressions were detected by Western blot analysis. A xenograft nude mice model of human gastric cancer was established to evaluate the anti-cancer effect of myrrh in vivo. RESULTS: Myrrh significantly inhibited cellular proliferation, migration, and induced apoptosis in vitro as well as inhibited tumor growth in vivo. In addition, myrrh inhibited the expression of PCNA, COX-2, and Bcl-2 as well as increased Bax expression in gastric cancer cells. CONCLUSION: Myrrh may inhibit the proliferation and migration of gastric cancer cells, as well as induced their apoptosis by down-regulating the expression of COX-2.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Commiphora , Ciclo-Oxigenase 2/metabolismo , Extratos Vegetais/farmacologia , Neoplasias Gástricas/tratamento farmacológico , Animais , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Commiphora/química , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos Nus , Invasividade Neoplásica , Extratos Vegetais/isolamento & purificação , Antígeno Nuclear de Célula em Proliferação/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais , Neoplasias Gástricas/enzimologia , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Proteína X Associada a bcl-2/metabolismo
5.
Ann Transl Med ; 8(7): 486, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32395530

RESUMO

BACKGROUND: Using deep learning techniques in image analysis is a dynamically emerging field. This study aims to use a convolutional neural network (CNN), a deep learning approach, to automatically classify esophageal cancer (EC) and distinguish it from premalignant lesions. METHODS: A total of 1,272 white-light images were adopted from 748 subjects, including normal cases, premalignant lesions, and cancerous lesions; 1,017 images were used to train the CNN, and another 255 images were examined to evaluate the CNN architecture. Our proposed CNN structure consists of two subnetworks (O-stream and P-stream). The original images were used as the inputs of the O-stream to extract the color and global features, and the pre-processed esophageal images were used as the inputs of the P-stream to extract the texture and detail features. RESULTS: The CNN system we developed achieved an accuracy of 85.83%, a sensitivity of 94.23%, and a specificity of 94.67% after the fusion of the 2 streams was accomplished. The classification accuracy of normal esophagus, premalignant lesion, and EC were 94.23%, 82.5%, and 77.14%, respectively, which shows a better performance than the Local Binary Patterns (LBP) + Support Vector Machine (SVM) and Histogram of Gradient (HOG) + SVM methods. A total of 8 of the 35 (22.85%) EC lesions were categorized as premalignant lesions because of their slightly reddish and flat lesions. CONCLUSIONS: The CNN system, with 2 streams, demonstrated high sensitivity and specificity with the endoscopic images. It obtained better detection performance than the currently used methods based on the same datasets and has great application prospects in assisting endoscopists to distinguish esophageal lesion subclasses.

6.
Eur J Pharmacol ; 680(1-3): 8-15, 2012 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-22329896

RESUMO

Both mycelium and fruiting body of Antrodia camphorate, a traditional medicinal fungus of the family Polyporaceae in Taiwan, have been suggested to possess multiple biological functions. However, there is little information on the anticancer components and actions of mycelium of Antrodia camphorate. In the present study, the anticancer potential of synthesized maleimide derivatives, which have been isolated from mycelium of Antrodia camphorate, is examined. Comparing the cytotoxicity of two synthesized maleimide derivatives in four human cancer cell lines, camphorataimide B displayed potent efficacy. Then we investigated the impact of camphorataimide B on cell survival and cell cycle progression in vitro, and tumor growth in vivo in MDA-MB-231 breast cancer cells. Camphorataimide B decreased the cell viability and foci formation of MDA-MB-231 breast cancer cells. Further, camphorataimide B triggered apoptosis and blocked cell cycle progression of MDA-MB-231 breast cancer cells. Using immunoblotting analysis, camphorataimide B decrease the expression of cyclin-A and cyclin-B1. Moreover, we demonstrated for the first time that camphorataimide B inhibited cyclooxygenase-2 (COX-2) activity and protein expression in MDA-MB-231 cells. In nude mice study, camphorataimide B administration retarded the xenograft tumor growth of MDA-MB-231 cells. By immunohistochemical analysis, camphorataimide B decreased the expression of Ki-67 in xenograft tumor in vivo. It implied that camphorataimide B blocked cell cycle progression. Consistent with the cell culture investigation, camphorataimide B also reduced the expression of cyclin-A, cyclin-B1 and COX-2 in xenograft tumor. Thus, camphorataimide B may play a crucial role in prevention and therapy of malignant breast cancer.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/enzimologia , Ciclo-Oxigenase 2/metabolismo , Maleimidas/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antrodia/química , Apoptose/efeitos dos fármacos , Apoptose/genética , Neoplasias da Mama/patologia , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Ciclina A/genética , Ciclina A/metabolismo , Ciclina B/genética , Ciclina B/metabolismo , Ciclo-Oxigenase 2/genética , Inibidores de Ciclo-Oxigenase 2/farmacologia , Feminino , Humanos , Antígeno Ki-67/genética , Antígeno Ki-67/metabolismo , Maleimidas/química , Maleimidas/isolamento & purificação , Camundongos , Camundongos Nus , Micélio/química , Ensaios Antitumorais Modelo de Xenoenxerto
7.
J Vet Med Sci ; 70(9): 1001-4, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18840980

RESUMO

Maxillary bone epithelial cyst is rare in dogs. A 5-year-old, spayed female miniature schnauzer developed a swelling below the nasal canthus of left eye. Plain radiograph demonstrated a 1.5 cm diameter of radiolucent lesion on the maxillary bone anteroventral to the eye, and contrast dacryocystorhinography confirmed an obstructed nasolarcrimal duct. The swelling showed poor response to antibiotic treatment but responded well to oral prednisolone. Exploratory surgery revealed a cyst-like structure filled with brown serous fluid. Histopathological examination of the removed cyst revealed a double cuboidal epithelial cyst. The dog recovered rapidly after surgery, and the swelling had not recurred for a 36-month follow-up. It is the first case of periorbital bone epithelial cyst reported in an adult miniature schnauzer.


Assuntos
Cistos Ósseos/veterinária , Doenças do Cão/patologia , Doenças do Cão/cirurgia , Maxila/diagnóstico por imagem , Animais , Cistos Ósseos/tratamento farmacológico , Cistos Ósseos/patologia , Cistos Ósseos/cirurgia , Doenças do Cão/tratamento farmacológico , Cães , Feminino , Prednisolona/uso terapêutico , Radiografia
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