71. pathological constituents of urine,
Nitrite (0) -The presence of nitrites in urine indicate the presence of coliform bacteria. This may be a sign of infection, however, the other parameters such as leukocyte esterase, urine white blood cell count, and symptoms such as dysuria, urgency, fevers and chills must be correlated to diagnose an infection.
Sodium (150-300mmol/day) - The sodium levels are frequently ordered during the workup of acute renal failure. The fractional excretion of sodium, abbreviated as FeNa is an important marker in distinguishing pre-renal from post-renal failure.
Potassium (40-90mmol/day) -Urine potassium may be ordered in the workup of hypokalemia. In case of GI loss of potassium, the urine potassium will be low. In case of renal loss of potassium, the urine potassium levels will be high. Decreased levels of urine potassium are also seen in hypoaldosteronism and adrenal insufficiency.
Proteins (0) - The detection of protein in urine, called proteinuria may indicate that the permeability of the glomerulus is abnormally increased. This may be caused by renal infections or it may be caused by other diseases that have secondarily affected the kidneys such as diabetes mellitus, jaundice, or hyperthyroidism.
Glucose -Presence of glucose in the urine is called glucosuria.
Bilirubin - An abnormally high level of blood bilirubin may result from: an increased rate of red blood cell destruction, liver damage, as in hepatitis and cirrhosis, and obstruction of the common bile duct as with gallstones. An increase in blood bilirubin results in jaundice, a condition characterized by a brownish yellow pigmentation of the skin and of the sclera of the eye.
Ketone bodies – ketonuria
White blood cells – infection.
Free cortisol - Values below threshold indicate Addison's disease, while values above indicate Cushing's syndrome. A value smaller than 200 nmol/24h (72 µg/24h[9]) strongly indicates absence of Cushing's syndrome.
72. Connective tissue is a fibrous tissue. Connective tissue makes up a variety of physical structures including, tendons, blood, cartilage, bone, adipose tissue, and lymphatic tissue. Structurally, connective tissue is formed by three classes of components: cells, fibers, and ground substance. The major constituent of connective tissue is the extracellular matrix. Extracellular matrices consist of different combinations of protein fibers (collagen, reticular, and elastic) and ground substance. Functions: Providing structural suport, Serving as a medium for exchange, Aiding in the defense and protection of the body, Forming a site for storage of fat.
| Ground substance is a hydrated, amorphous material that is composed of glycosaminoglycans, long unbranched polymers of repeating disaccharides; proteoglycans, protein cores to which various glycosaminoglycans are covalently linked; and adhesive glycoproteins, large macromolecules responsible for fastening the various components of the extracellular matrix to one another and to integrins and dystroglycans of the cell membrane. |
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| Glycosaminoglycans are of two major types: sulfated, including keratan sulfate, heparan sulfate, heparin, chondroitin sulfates, and dermatan sulfate; and nonsulfated, including hyaluronic acid. |
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| Proteoglycans are covalently linked to hyaluronic acid, forming huge macromolecules called aggrecan aggregates, which are responsible for the gel state of the extracellular matrix. |
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Fibers of the extracellular matrix are collagen (and reticular) and elastic fibers. Collagen fibers are inelastic and possess great tensile strength. Each fiber is composed of fine subunits, the tropocollagen molecule, composed of three α-chains wrapped around one another in a helical configuration. About 20 different types of collagen fibers are known, which vary in the amino acid sequences of their α-chains. The most common amino acids of collagen are glycine, proline, hydroxyproline, and hydroxylysine.
Elastic fibers are composed of elastin and microfibrils. These fibers are highly elastic and may be stretched to 150% of their resting length without breaking. Their elasticity is due to the protein elastin, and their stability is due to the presence of microfibrils. Elastin is an amorphous material whose main amino acid components are glycine and proline. Additionally, elastin is rich in lysine, the amino acid responsible for the formation of the highly deformable desmosine residues that impart a high degree of elasticity to these fibers.
Cells: a) fixed: Fibroblasts, Adipose cells, Pericytes, Mast cells, Macrophages. B) transient: Plasma cells, Lymphocytes, Neutrophils, Eosinophils, Basophils, Monocytes, Macrophages.