Spindle-shaped cells

The scoring of foci was carried out according to the recommended guidelines. Only foci considered as positive (type III), showing deeply basophilic, dense multilayering of cells, random cell orientation at all parts of the focus edge, invasion into the surrounding contact-inhibited monolayer, and domination of spindle-shaped cells, were counted. 

In 1846, Virchow first recognized the existence in the CNS of a fragile, non-nervous, interstitial component made up of stellate or spindle-shaped cells, morphologically distinct from neurons, which he named neuroglia, or... 

Smooth muscle is composed of spindle-shaped cells rather than fibres. It lacks striations since adjacent myofibrils are out of register. Power output is lower than that from skeletal muscle it is responsible for the gentler, involuntary movements including, for example, those that cause movement of the intestine and those that change the diameter of blood vessels. 

Fibroblasts live in the spaces between other cells and secrete the proteins of the extracellular matrix, e.g. collagen. They do not associate tightly with one another or with other cell types, but they do readily attach themselves to a substratum. In dilute culture they are observed as individual spindle shaped cells which move around the surface of the culture vessel avoiding each other. As their density increases they tend to align themselves in parallel assays (Fig. 2.1). However, fibroblasts can become chondrocytes or adipocytes in the appropriate environment (Taylor and Jones, 1979) and on transformation ( 2.2) they readily lose their contact inhibition and pile up on top of one another (Fig. 2.1)... 

The average hair is composed of about 90% keratin, a fibrous protein, and about 10% water. Each hair consists of two or three layers. The outer layer is a sheath called the cuticle, which is thin and colorless. It is made up of overlapping scales in layers. Inside the cuticle are the long spindle-shaped cells of the cortex, which makes up the bulk of the hair. These cells also contain whatever pigments are present in the hair. The innermost layer, which is only present in large thick hair, is the medulla or pith. 

The sinoatrial node (SA), consisting of spindle-shaped cells, initiates the electrical activity of the heart. From its location in the right atrium in proximity to the superior vena cava, the electrical activity spreads to the atria whose cells are larger than those of the SA. The pulse from the atria spreads to the atrioventricular node (AV), the gateway to the ventricles. The atria and the ventricles are electrically isolated. The AV node also slows down the electrical activity giving the atria time to fill. The bundle of His is the upper end of the electrical path, which through the Purkinje fibers allows the electrical signal to activate the ventricles and thus to pump the blood. 

The cortex forms the bulk of fine animal hairs and is derived from highly differentiated spindle-shaped cells that are densely packed with keratinous proteins. The long axes of the cortical cells are oriented parallel to the fiber length, and elongated cavities near the center of the cells are similarly oriented. These cavities are derived from the nuclei of the developing cells and contain debris usually referred to as nuclear remnants. Between cortical cells there is a layer 250-300 A in thickness which is similar to that found between cuticle cells this also is referred to sometimes as intercellular cement. Many nonkeratinous inclusions are found within the cortical cells and these are believed to be cytoplasmic debris. 

Benelli, R., Albini, A., Parravicini, C., Carlone, S., Repetto, L., Tambussi, G. and Lazzarin, A. (1996). Isolation of spindle-shaped cell populations from primary cultures of Kaposi s Sarcoma of different stage. Cancer Lett. 100, 125-132. 

Katano H, Sato Y, Kurata T, et al. High expression of HHV-8-encoded ORF73 protein in spindle-shape cells of Kaposi s sarcoma. Am J Pathol. 1999 155 47-52. 

On histologic analysis a mass with spindle shaped cells surrounded by a mucopolysaccharide rich stroma with necrosis or hemorrhagic tissue, and surrounded by a fibrous pseudocapsule will be seen in a great number of cases. 

Cortex Filament in matrix Cortex cells (spindle shape) Cell membrane complex... 

Muscle whose activity is not under the control of the will It Is supplied by the autonomic nervous system. Involuntary muscle comprises long spindle-shaped cells without striations. These cells occur singly, in groups, or as sheets in the skin, around hair follicles, and in the digestive tract, respiratory tract, urinogenital tract, and the circulatory system. The cells contract slowly in spontaneous rhythms or when stretched they may show sustained contraction (tonus) for long periods without fatigue. Compare cardiac muscle voluntary muscle. 

Wood is primarily composed of hollow, elongated, spindle-shaped cells (called tracheids or fibers) that are arranged parallel to each other along the trunk of the tree [9]. These fibers are firmly cemented together and form the structural component of wood tissue. Fibers are extracted from wood by mechanical or chemical means during the pulping process. 

The majority part of the interior of the fiber mass is the cortex, which, from the point of view of mechanical properties, is also the most important component. The cortex consists of elongated, spindle-shaped cells aligned in the direction of the fiber axis. Within these cells resides the major part of the keratinized protein in the form of macrofibrils, which in turn are formed by lower levels of organization, i.e., microfibrils and finally protofibrils. The latter two are low-sulfur proteins and more or less crystalline in nature with their a-helical parts as crystalline lattice components. They are embedded in a noncrystalline, nonfibrillar matrix of disulfide cross-linked, globular proteins. 

The Chang liver cells are cultured in parafBn-sealed 96-weU miCTolitre plates (24 h). Deficient outgrowth of fusiform or spindle-shaped cells is used as a criterion of cyto-inhibition (Ekwall and Sandstrom, 1978), after the cells have been in contact with the test substance. 

The cortical layer, the cortex, is located tmder the cuticle and forms the main mass of the fiber and, consequently, defines basic physico-mechanical and many other properties of the wool. Cortex is composed of spindle-shaped cells connivent to one another. Protein substance is also located between the cells. 

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