ENTRIES A–Z
Philip Winn in Dictionary of Biological Psychology, 2003
Histology is the study of the microscopic structure of biological tissues. It is a subdiscipline of anatomy, and is also called microscopic anatomy. The typical cell types in the brain are NEURONS and glia. Neurons have a SOMA (cell body), dendrites (see DENDRITE) and an AXON. Glial cells, usually smaller than neurons, have a cell body and processes, but no axon. Glial cells are classified into ASTROGLIA, MICROGLIA and OLIGODENDROGLIA, each of which has a distinct MORPHOLOGY. These cells and their cellular elements can be studied with histological staining methods. Histological techniques are also used to examine pathological structures such as various types of TUMOUR, GLIOSIS and AMYLOID deposits in ALZHEIMER'S DEMENTIA. Most histological methods are applicable to all biological tissues, but certain staining methods are specifically developed for neural tissues which contain unique elements. The following summarizes the histological methods that are commonly used for neural tissues.
Experimental Methods in Cardiovascular Mechanics
Michel R. Labrosse in Cardiovascular Mechanics, 2018
Histology, the study of the microscopic anatomy of cells and tissues (Hillman 2000), has spawned many useful techniques since the second half of the nineteenth century (Table 4.1). These techniques have progressively combined with methods from physics and materials science such as electron microscopy, polarized light microscopy, Fourier-transform infrared spectroscopy, optical coherence tomography, confocal laser scanning microscopy, second harmonic generation, and two-photon excited fluorescence (Bergholt et al. 2016). However, these methods remain qualitative or semiquantitative in nature, and although they might, under the right circumstances, provide insight into the relative spatial distributions of the major constituents of the ECM, they are usually limited by the spatial resolution that they can achieve (Bergholt et al. 2016).
The Analyzed Body
Roger Cooter, John Pickstone in Medicine in the Twentieth Century, 2020
The anatomical tradition, so important in the development of clinical medicine, was also of central importance in the development of analysis in the laboratory, the key site for analysts in twentieth-century medicine. Morbid anatomy originating in the autopsy room constitutes one of the sources of modern pathological understanding and techniques. In the course of the nineteenth century the pathologico-anatomical correlations, which initially focused on the gross pathology of organs, shifted to the analysis of diseased tissues, and then of cells. The developments in histology and cell-theory, the use of improved microscopes (from the 1830s), and new fixing, sectioning, and staining techniques (in the second half of the nineteenth century) promoted the observation and classification of morphological changes in ever smaller structures and in ever finer detail. As the attention of researchers shifted from organs to tissues and cells, so did the manner in which they localized, differentiated, and classified pathologies. These changes were also accompanied by the establishment of the new locations where pathological work took place: the dissecting room came to be supplemented first by the research laboratory, and then the clinical pathological laboratory.
Chronic exposure to multi-metals on testicular toxicity in rats
Published in Toxicology Mechanisms and Methods, 2021
Amit Gupta, Anoop Kumar, Saba Naqvi, Swaran J. S. Flora
Histological studies are useful for the microscopic anatomy of biological tissues. In accordance with earlier reports, our investigation also showed that exposure to aluminum and copper alone and during co-exposure induced histological changes in testis such as disorganization of somniferous tubules, necrosis, and absence of mature spermatids in somniferous tubules (Sakhaee et al. 2016; Sun et al. 2018). These alterations are indicative of interference with important processes such as spermatogenesis and steroidogenesis. Several studies have been done on aluminum and copper-related changes in testicular histopathology which exhibited the degeneration of these epithelial cells as the main cause of testicular damage (Adedara et al. 2017; Martinez et al. 2017; Chen et al. 2020). On the other hand, zinc exposed animals showed well organized somniferous tubule and mature spermatids in the tubules without any contraction of the lumen (Chemek et al. 2016).
Curriculum reform and evolution: Innovative content and processes at one US medical school
Published in Medical Teacher, 2019
Janet E. Fischel, Doreen M. Olvet, Richard J. Iuli, Wei-Hsin Lu, Latha Chandran
The new LEARN curriculum abandoned the more traditional framework of courses based on advancing years in medical school and several solo, departmentally based courses that had focused rather exclusively on specific subjects, such as physiology, pathology, and pharmacology. Instead, Biomedical Building Blocks, the first major course in Phase I, is composed of a 6-month, integrated basic science experience that is not departmentally based. The course presents key concepts in anatomy, histology, genetics, biochemistry, immunology, pathology, and infectious diseases (see Figure 1). Following this course is a sequence of four pathophysiology systems-based blocks that integrate the basic and clinical sciences conceptually: cardiovascular–pulmonary–renal, mind–brain-behavior, endocrine–reproductive, and gastrointestinal–nutrition. Two longitudinal courses span Phase I: Introduction to Clinical Medicine and Medicine in Contemporary Society.
Do we really need cadavers anymore to learn anatomy in undergraduate medicine?
Published in Medical Teacher, 2018
P. G. McMenamin, J. McLachlan, A. Wilson, J. M. McBride, J. Pickering, D. J. R. Evans, A. Winkelmann
The students need to know the anatomy content of their course, but they also need to know how to use this content to solve complex problems. For example, lung cancer is a complex problem. It is one of the most common and serious types of cancer in the United Kingdom, with 45,000 diagnoses per year. If someone suspects they have lung cancer, what do they do? They go to the doctor. What does their doctor do? Examine them, listen to their chest, auscultate, palpate, percuss - living anatomy. They will potentially send them for a CT scan, a chest x-ray and then interpret these findings—radiological anatomy. They may do a lung volume test to calculate capacity—functional anatomy. They may go for a biopsy and examine the histology—microanatomy—and then assess for pathology—abnormal anatomy. Only once the patient has gone through this sequence may they go and have surgery to examine the macro-anatomy—gross anatomy.