ABSTRACT
Widespread cortical accumulation of misfolded pathological tau proteins (ptau) in the form of paired helical filaments is a major hallmark of Alzheimer's disease. Subcellular localization of ptau at various stages of disease progression is likely to be informative of the cellular mechanisms involving its spread. Here, we found that the density of ptau within several distinct rostral thalamic nuclei in post-mortem human tissue (n = 25 cases) increased with the disease stage, with the anterodorsal nucleus (ADn) consistently being the most affected. In the ADn, ptau-positive elements were present already in the pre-cortical (Braak 0) stage. Tau pathology preferentially affected the calretinin-expressing subpopulation of glutamatergic neurons in the ADn. At the subcellular level, we detected ptau immunoreactivity in ADn cell bodies, dendrites, and in a specialized type of presynaptic terminal that expresses vesicular glutamate transporter 2 (vGLUT2) and likely originates from the mammillary body. The ptau-containing terminals displayed signs of degeneration, including endosomal/lysosomal organelles. In contrast, corticothalamic axon terminals lacked ptau. The data demonstrate the involvement of a specific cell population in ADn at the onset of the disease. The presence of ptau in subcortical glutamatergic presynaptic terminals supports hypotheses about the transsynaptic spread of tau selectively affecting specialized axonal pathways.
Subject(s)
Alzheimer Disease , tau Proteins , Humans , tau Proteins/metabolism , Female , Male , Aged , Aged, 80 and over , Alzheimer Disease/pathology , Alzheimer Disease/metabolism , Middle Aged , Neurons/metabolism , Neurons/pathology , Vesicular Glutamate Transport Protein 2/metabolism , Glutamic Acid/metabolism , Anterior Thalamic Nuclei/metabolism , Anterior Thalamic Nuclei/pathology , Calbindin 2/metabolism , Neurofibrillary Tangles/pathology , Neurofibrillary Tangles/metabolism , Presynaptic Terminals/metabolism , Presynaptic Terminals/pathologyABSTRACT
In recent years a significant demand to develop computer-assisted diagnostic tools to assess prostate cancer using whole slide images has been observed. In this study we develop and validate a machine learning system for cancer assessment, inclusive of detection of perineural invasion and measurement of cancer portion to meet clinical reporting needs. The system analyses the whole slide image in three consecutive stages: tissue detection, classification, and slide level analysis. The whole slide image is divided into smaller regions (patches). The tissue detection stage relies upon traditional machine learning to identify WSI patches containing tissue, which are then further assessed at the classification stage where deep learning algorithms are employed to detect and classify cancer tissue. At the slide level analysis stage, entire slide level information is generated by aggregating all the patch level information of the slide. A total of 2340 haematoxylin and eosin stained slides were used to train and validate the system. A medical team consisting of 11 board certified pathologists with prostatic pathology subspeciality competences working independently in 4 different medical centres performed the annotations. Pixel-level annotation based on an agreed set of 10 annotation terms, determined based on medical relevance and prevalence, was created by the team. The system achieved an accuracy of 99.53% in tissue detection, with sensitivity and specificity respectively of 99.78% and 99.12%. The system achieved an accuracy of 92.80% in classifying tissue terms, with sensitivity and specificity respectively 92.61% and 99.25%, when 5x magnification level was used. For 10x magnification, these values were respectively 91.04%, 90.49%, and 99.07%. For 20x magnification they were 84.71%, 83.95%, 90.13%.
Subject(s)
Prostatic Neoplasms , Humans , Prostatic Neoplasms/diagnosis , Prostatic Neoplasms/pathology , Male , Artificial Intelligence , Machine Learning , Image Interpretation, Computer-Assisted/methods , Algorithms , Sensitivity and Specificity , Diagnosis, Computer-Assisted/methods , Deep Learning , Image Processing, Computer-Assisted/methodsABSTRACT
ABSTRACT: The urocortin 1 (UCN1)-expressing centrally projecting Edinger-Westphal (EWcp) nucleus is influenced by circadian rhythms, hormones, stress, and pain, all known migraine triggers. Our study investigated EWcp's potential involvement in migraine. Using RNAscope in situ hybridization and immunostaining, we examined the expression of calcitonin gene-related peptide (CGRP) receptor components in both mouse and human EWcp and dorsal raphe nucleus (DRN). Tracing study examined connection between EWcp and the spinal trigeminal nucleus (STN). The intraperitoneal CGRP injection model of migraine was applied and validated by light-dark box, and von Frey assays in mice, in situ hybridization combined with immunostaining, were used to assess the functional-morphological changes. The functional connectivity matrix of EW was examined using functional magnetic resonance imaging in control humans and interictal migraineurs. We proved the expression of CGRP receptor components in both murine and human DRN and EWcp. We identified a direct urocortinergic projection from EWcp to the STN. Photophobic behavior, periorbital hyperalgesia, increased c-fos gene-encoded protein immunoreactivity in the lateral periaqueductal gray matter and trigeminal ganglia, and phosphorylated c-AMP-responsive element binding protein in the STN supported the efficacy of CGRP-induced migraine-like state. Calcitonin gene-related peptide administration also increased c-fos gene-encoded protein expression, Ucn1 mRNA, and peptide content in EWcp/UCN1 neurons while reducing serotonin and tryptophan hydroxylase-2 levels in the DRN. Targeted ablation of EWcp/UCN1 neurons induced hyperalgesia. A positive functional connectivity between EW and STN as well as DRN has been identified by functional magnetic resonance imaging. The presented data strongly suggest the regulatory role of EWcp/UCN1 neurons in migraine through the STN and DRN with high translational value.
ABSTRACT
Although computerised information technology, including the Internet is broadly used and globally accessible it is still not a significant form of professional communications in diagnostic histopathology. The high cost of interactive dynamic telepathology systems makes their use limited outside the richest economies. In contrast static telepathology systems are relatively cheap but in practice their information content can be heavily biased by the choice of images sent by the consulting pathologist. The degree of this bias may be regarded simply as the amount of information transferred to a remote location expressed as a percentage of the total information present in the histological sample. We refer to this as the percentage of explicit versus implicit information. Another major source of bias may be found in the information transmitted in written or verbal discussion with a remote consultant. We have developed a system of static telepathology, the image pyramid, which attempts to minimise bias by transferring all of the information in a section to the consultant. It is inexpensive and should prove to be widely accessible.
Subject(s)
Telepathology/methods , Data Display , Humans , Image Processing, Computer-Assisted , InternetABSTRACT
The four main aspects of applied medical information technology, which change the traditional systems of the entire health service are signal and data processing, digital modelling and interface optimisation. The information technology serving individual clinical specialties including clinical histopathology is changing at each of the four levels resulting in transformation of the communication paradigms. The object of investigation in histopathology is the digital slide, which is accessible throughout the world with no time or geographical limits. It permits the digital modelling of routine histological and/or cytological slide and it also allows measurements by using image analysis or stereology software packages. The electronic slide can be viewed, examined and diagnosed on a computer connected to a microscope, a new interface in diagnostic histopathology. This study describes the main theoretical and practical aspects, including challenges, of digital pathology and it also discusses the conditions required for successful information management. It reviews the experiences of the last one and half decades gained in the field of pathological information technology in Hungary including its main episodes and milestones of development. Introducing its present state, this paper describes the concept and the mode of investigation of the digital slide. It shows the development and use of a virtual microscope in Hungary. Based on know-how including the British experience this review describes the possible uses of digital slides, which by improving communication could have a positive effect on the entire health care system. It summarises the possible and necessary components of a digital pathology laboratory, which may include the new Slide Archive and Communication System (SACS). Using experimental data it mentions the possibility of generating primary digital pathological sample and producing the so called optical biopsy with no need for removing tissue from the patient.