Testing of compounds for carcinogenic potential in vivo involves various experimental designs. A few of these techniques are directed to demonstrate the genotoxicity and mutagenicity of the compound by histopathology....Testing of compounds for carcinogenic potential in vivo involves various experimental designs. A few of these techniques are directed to demonstrate the genotoxicity and mutagenicity of the compound by histopathology. These changes shown by histochemical means include monoclonal antibody directed cellular markers. Development of the polymerase chain reaction technique (PCR) for amplification of DNA has facilitated the investigation of molecular events related to the formation of malignant neoplasms. We describe here a method for screening tissues for mutations of the H-ras gene using monoclonal antibodies directed toward normal and mutant p21 proteins. Formalin-fixed, paraffin-embedded tissue sections are used to subsequently confirm the gene mutation by PCR amplification of the H-ras gene. The results indicated a successful application of this technique to demonstrate the presence of p21 oncoprotein in the tissues tested.展开更多
Objective:This article describes a new method(VS-FPM)for analysis of unstained tissues based on the application of supervised machine learning to generate brightfield hematoxylin and eosin(H&E)images from phase im...Objective:This article describes a new method(VS-FPM)for analysis of unstained tissues based on the application of supervised machine learning to generate brightfield hematoxylin and eosin(H&E)images from phase images recovered using Fourier ptychographic microscopy(FPM).Impact Statement:VS-FPM has several advantages for label-free digital pathology.Capture of complex image information simplifies model training and allows post-capture refocusing.FPM images combine high resolution with a large field of view,and the hardware is low-cost and compatible with many existing brightfield microscope systems.Introduction:By generating realistic histologically stained images from label-free image data,virtual staining(VS)methods have the potential to streamline clinical workflows,improve image consistency,and enable new ways of visualizing and analyzing histological tissues.Methods:We trained a conditional generative adversarial network to translate high-resolution FPM images of unstained tissues to brightfield H&E images and assessed the method using diagnosis of colonic polyps as a test case.Results:We found no statistically significant difference between the spatial resolution of FPM images captured at 4×magnification and images from a pathology slide scanner at 20×magnification.Visual assessment and image similarity metrics showed that VS-FPM images of unstained tissues closely resemble images of chemically H&Estained tissues.However,the spatial resolution of virtual H&E images was approximately 20%lower than equivalent images of chemically stained tissues.Using VS-FPM,board-certified pathologists were able to accurately distinguish normal from dysplastic tissues and derive correct pathological diagnoses.Conclusion:VS-FPM is a reliable,accessible VS method that also overcomes many other limitations inherent to histopathology microscopy.展开更多
文摘Testing of compounds for carcinogenic potential in vivo involves various experimental designs. A few of these techniques are directed to demonstrate the genotoxicity and mutagenicity of the compound by histopathology. These changes shown by histochemical means include monoclonal antibody directed cellular markers. Development of the polymerase chain reaction technique (PCR) for amplification of DNA has facilitated the investigation of molecular events related to the formation of malignant neoplasms. We describe here a method for screening tissues for mutations of the H-ras gene using monoclonal antibodies directed toward normal and mutant p21 proteins. Formalin-fixed, paraffin-embedded tissue sections are used to subsequently confirm the gene mutation by PCR amplification of the H-ras gene. The results indicated a successful application of this technique to demonstrate the presence of p21 oncoprotein in the tissues tested.
基金funded by a proof-of-concept award from Wellcome/EPSRC Centre for Interventional and Surgical Science(award 203145Z/16/Z)the NIHR UCLH Biomedical Research Centre(award 187809).A.P.L.was funded by The Pathological Society of Great Britain and Ireland.
文摘Objective:This article describes a new method(VS-FPM)for analysis of unstained tissues based on the application of supervised machine learning to generate brightfield hematoxylin and eosin(H&E)images from phase images recovered using Fourier ptychographic microscopy(FPM).Impact Statement:VS-FPM has several advantages for label-free digital pathology.Capture of complex image information simplifies model training and allows post-capture refocusing.FPM images combine high resolution with a large field of view,and the hardware is low-cost and compatible with many existing brightfield microscope systems.Introduction:By generating realistic histologically stained images from label-free image data,virtual staining(VS)methods have the potential to streamline clinical workflows,improve image consistency,and enable new ways of visualizing and analyzing histological tissues.Methods:We trained a conditional generative adversarial network to translate high-resolution FPM images of unstained tissues to brightfield H&E images and assessed the method using diagnosis of colonic polyps as a test case.Results:We found no statistically significant difference between the spatial resolution of FPM images captured at 4×magnification and images from a pathology slide scanner at 20×magnification.Visual assessment and image similarity metrics showed that VS-FPM images of unstained tissues closely resemble images of chemically H&Estained tissues.However,the spatial resolution of virtual H&E images was approximately 20%lower than equivalent images of chemically stained tissues.Using VS-FPM,board-certified pathologists were able to accurately distinguish normal from dysplastic tissues and derive correct pathological diagnoses.Conclusion:VS-FPM is a reliable,accessible VS method that also overcomes many other limitations inherent to histopathology microscopy.
