Cellular pathology: importance of dyes in identifying normal and abnormal histological features of tissues

IntroductionIn the psychoanalyse of wind papers, histological maculation is important in order to study cellular body constructions, intracellular and extracellular substances at the microscopic level (Stevens and Lowe, 1997). spotting is an auxiliary technique used in microscopy to enhance contrast in images obtained and to high sparkle social systems. Stains may be used to define and examine bulge out tissues, cell populations or organelles within individual cells histological features useful for biologic look into and/or diagnosis in medicine (Bancroft and Cook, 1994). The importance of dyes in identifying normal and vicarious histological features of tissues is herein discussed. Medical and biological interrogation is underpinned by knowledge of the normal organize and puzzle out of cells and tissues as s intumesce as the organs and organises they make up (histology) Understanding indisposition in the context of structure-function relationships (histopathology) mo difys distinguishableiation between normal tissues and abnormal tissues in a particular disease state (Cook, 2008). The differentiation of these enabled by the identification and intellectual of the divergence of normal and abnormal histology is highly beneficial in disease diagnostics and therapeutics (Bancroft and Gamble, 2008). Such essential study disciplines are based on a thorough understanding and ability to recognise basic tissue types which combine to form the different organs of the body. Understanding normal structure of tissues is essential to the identification of altered structure (Lakhani, et al., 1998). With knowledge of normal histology, unitary can see the types, location and scope of cells involved in disease, whether their congenital morphology is impacted indicating cellular dysfunction, and whether higher order tissue structure is impaired which indicates organ dysfunction (Stevens and Lowe, 2000).Histopathology, on the some other hand, encompasses the mea ns to asseverate accurate models of particular diseases based on understanding the visual personation of molecular mechanisms differentiated from normal (Kiernan, 1999). In the normal wellnessy state, cells and other elements of tissue are arranged in regular recognisable patterns. Tissues unremarkably fetch particular defining characteristics such as surface structure and shapes and formations of constituent cells which are used in their identification and assessment of function (Stevens and Lowe, 1997). Changes in these patterns can be induced by a colossal range of chemical and physical influences such as microbial transmittance and cell malignancy in cancer are reflected by morphological alterations at the microscopic level (Lakhani, et al., 1998). Many diseases such as crab louse are also characterised by typical structural and chemical abnormalities which take leave the normal pattern of tissues (Lakhani et al., 1998). This is the basis of microscopic examination of s pecimens. Examination of mingled specimen and differentiation of structures is challenged as tissue sections or smears obtained from biopsies or aspirations start dull and less expound when viewed in sluttish microscopy. This is because the fixed materials in the preparation have a similar refractive index and have a similar grey colour which makes it difficult to identify the structure of the tissues (Kiernan, 1999). It is essential to stain the cells/tissues to enable better visualisation of the different structures in contrasting colours (Bancroft and Cook, 1994). Staining is most commonly carried out through and through the use of histological dyes which are coloured organic compounds obtained from natural sources or from synthetic production that selectively bind to or concentrate in various cell and tissue structures (Kiernan, 1999). Dyes contain auxochromes which are chemical components that enable attachment to tissue such as the ionisable OH group, and chromophores whic h are substances added to absorb clear light responsible for the colour observed. Colour arises when an attached chromophore molecule absorbs certain wavelengths of visible light (Bancroft and Gamble, 2008). Most modern dyes such as the Haematoxylin and bromeosin stains commonly used are synthesised from simpler organic molecules, usually benzene or one of its derivatives (Kiernan, 1999). Stains are generally aimed as special probes, which possess varying specificity depending on the unique ionization or chemical reaction with tissue structures and components (Stevens and Lowe, 1997). Staining does not result in a random act upon of the tissue specimens, but rather exploits the differences in the chemical structure of the tissue. This is shown by colour variation depending on which dye is bound. Colours acquired reflect the record of the tissues and their properties and proffers an advantage in the revelation of specific parts or areas (Cook, 2008). This enables particular vi sualisation of structures including cell structures such as the cytoplasm, nucleus and organelles, as well as extra-cellular components. Additionally, under certain conditions such as glycogen warehousing diseases, staining (in this case using the Periodic acid-Schiff (PAS) to detect carbohydrates) can uncover molecular compounds and differences associated with pathological conditions (Lakhani, et al., 1998). Enhanced capacity for visualisation and identification of structures is the primary feather advantage for the use of dyes in staining of tissue specimen. Tissue staining therefore plays a hypercritical role in tissue-based diagnosis and research acknowledgeing the visualization of tissue morphology and histological features, and in distinguishing normal and abnormal histological features (Cook, 2008 Stevens and Lowe, 1997 Kiernan, 1999). These observations are sufficient to allow analysis of tissue health and diagnosis of disease. Histological dyes commonly used for staini ng in light microscopy include the Haematoxylin and Eosin stain (H&038E), Van Giessen, Massons Trichrome, and Periodic acid-Schiff (PAS), among others. The H&038E stain is the most commonly used stain for light microscopy in histology and histopathology. It is routinely used as it provides a very detailed view of the tissue achieved by staining cell structures staining the nuclei a dark blue or purple, and the cytoplasm and connective tissue in shades of pink (Cook, 2008). Staining using these and other dyes forms a critical part of the diagnostic picture given the sufficient contrast obtained for the presentment of tissue morphology (Stevens and Lowe, 1997).In conclusion, staining is an essential process in histology and histopathology with its primary advantage being the enhancement of contrast between different components of the tissue specimen, particularly as seen in light microscopy. The overall verifiable of histology is to acquire knowledge of normal tissues and organs, wh ich is essential to understanding the altered structure and function of diseased cells, tissues and organs. There is no doubt that the use of dyes to allow for differentiation between normal and abnormal tissues is fundamental to our understanding of this.ReferencesBancroft, J., and Gamble, M., (2008). opening and practice of histological techniques. PA, USA ElsevierBancroft, D. and Cook C., (1994). Manual of Histological Techniques and their diagnostic Application. PA, USAChurchill Livingstone Elsevier.Cook, D., (2008) Cellular Pathology. 2nd Edition, Chatham Scion Publishing Ltd.Kiernan, A., (1999). Histological and Histochemical Methods. Theory and send (3rd Ed). Oxford Butterworth-Heinemann.Lakhani, R., Dilly, A., and Finalyson, J., (1998) Basic Pathology An Introduction to the Mechanisms of Disease (2nd Ed). London Arnold.Stevens, A., and Lowe, J., (1997). Human Histology. 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