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Hemoglobin H, consisting of beta chain tetramers, is an unstable hemoglobin which forms precipitates just below the red blood cell membrane. This precipitated hemoglobin inclusion can be observed when red blood cells are stained with Brilliant Cresyl Blue (BCB). Hemoglobin H bodies are seen as faint blue inclusions. They appear to be on the outside of the cell, resembling sugar on a gumdrop; however, in actuality these inclusions are located just inside the red blood cell's membrane and push outward.

The presence of significant amounts of glucose in the urine is called glycosuria (or glucosuria). The amount of glucose present in urine is dependent upon the blood glucose level, the rate of glomerular filtration, and the degree of tubular reabsorption of the sugar. Usually glucose will not be present in the urine until the blood level exceeds 160-189 mg/dL, which is the normal renal threshold for glucose. The main reason for glycosuria is an elevated blood glucose level (hyperglycemia). Diabetes mellitus is the most common cause of hyperglycemia. However, stress, obesity, brain injury, myocardial infarction, hyperthyroidism, pregnancy, and a lowered renal threshold due to kidney damage can all cause glycosuria.

Prompt testing (within two hours of urine specimen collection) or refrigeration of the specimen is necessary because the glycolytic enzymes from the cells and bacteria, if present, will decrease the sugar in the urine.

Enzyme-based methods are most often used to detect/monitor urine glucose and copper reduction methods are used to detect all reducing substances. Most enzyme tests use the enzyme glucose oxidase. which is impregnated on a dipstick along with a chromagen. These enzyme-based dipstick tests are specific for glucose.

Screening for ketonuria is useful in following the effects of treatment for diabetes and in judging the severity of acidosis. Large amounts of ketones will appear in the urine before serum ketone levels are elevated.

Two nucleic acids store and transfer cellular information in cells: Deoxyribonucleic Acid (DNA) Ribonucleic Acid (RNA)Strands of DNA and RNA are formed by the linkage of nucleotides. Each nucleotide is composed of a pentose sugar, a nitrogenous base, and a phosphate group.

Specific sugars, attached to the red cell membrane in unvarying linkage conformations, determine ABO antigenic activity. Galactose resides at the end of this specific sugar chain. This configuration constitutes the ABO antigen precursor substance.

Without H substance (also known as H antigen or substance H), there is no way for additional sugar attachment to take place. Additional sugar attachment is necessary for the development of A and B antigens. Therefore, without substance H there is no development of A and B antigens. Once substance H is developed, the addition of the sugar N-acetylgalactosamine to the terminal position of the chain gives the molecule "A" antigenic activity.

According to the American Heart Association, the risk factors for metabolic syndrome include:Abdominal obesity (excessive fat tissue in and around the abdomen) Atherogenic dyslipidemia (blood fat disorders – high triglycerides, low HDL cholesterol and high LDL cholesterol – that foster plaque buildups in artery walls) Elevated blood pressure Insulin resistance or glucose intolerance (the body can't properly use insulin or blood sugar) Prothrombotic state (e.g., high fibrinogen or plasminogen activator inhibitor–1 in the blood) Proinflammatory state (e.g., elevated high sensitivity C-reactive protein in the blood) Reference: Metabolic syndrome.The American Heart Association website. Available at:http://www.heart.org/HEARTORG/Conditions/More/MetabolicSyndrome/Metabolic-Syndrome_UCM_002080_SubHomePage.jsp#. Accessed December 5, 2011.

Staphylococcus aureus, particularly methicillin resistant strains (MRSA), have represented a likely target for molecular development, particularly in blood cultures. As more institutions implement patient screening protocols for MRSA, replacement of routine culture methods with molecular assays has gained increasing attention.PNA-FISH assays provide for the definitive identification of Staphylococcus aureus from positive blood culture vials. Peptide nucleic acid fluorescent in-situ hybridization is a relatively straight forward procedure that does not involve amplification and has limited equipment requirements. Procedurally it is easy to perform with minimal hands on time.PNA is a synthetic imitator of a nucleic acid sequence in which the backbone is a pseudopeptide rather than a sugar. PNA behaves similarly to DNA and will bind to complementary nucleic acid strands. A PNA probe is constructed, utilizing a complementary, hybridizing sequence for a known nucleic acid target sequence. The probe is typically bound to a fluorescent protein as a means of visualizing/detecting the target. In one commercially available method, once a blood culture vial demonstrates gram-positive cocci in clusters, a drop of the blood culture broth is added to fixation solution on a slide. Heat or methanol is used to fix the smear. After fixation, probe that targets species-specific ribosomal RNA is added to the smear, which is then cover-slipped.Slides are then incubated at 55oC. Post incubation, slides are immersed in a preheated wash solution and coverslips gently removed. After incubation in the wash solution, smears are air dried; a drop of mounting medium is added and the slide is cover-slipped again.The slides are examined with a fluorescent microscope, utilizing specific filters. Green fluorescing cocci in clusters are identified as Staphylococcus aureus. This identification would be available, depending on the routine identification system utilized, potentially 24 hours earlier than the norm.A significant number of blood cultures that demonstrate gram-positive cocci in clusters yield coagulase negative staphylococci (CNS), which represent potential contaminants, rather than significant infection. What is the significance of differentiating blood cultures that contain S. aureus from those that are growing CNS in a much earlier timeframe?Studies have shown that IF the differentiation of CNS from S. aureus is effectively communicated to clinicians and pharmacy/antimicrobial stewardship teams, active assessment can occur utilizing defined exclusion criteria for those patients whose cultures yielded CNS rather than S. aureus. In scenarios where contamination rather than infection is indicated, vancomycin can be discontinued earlier, and length of hospital stay is also shortened. Reduced antibiotic exposure, reduced risk of development of resistance, and reduced cost are all potential benefits.

Consists of an electrolyte panel, plus: Blood urea nitrogen (BUN), which a measure of renal function. Creatinine (Creat), which also measures renal function Glucose, the most important blood sugar, and Calcium. Run on serum or plasma

Sugars are also dissolved in the plasma. By far the most important is glucose. Blood glucose is increased in diabetes mellitus, and decreased in hypoglycemia.

Genetic information is carried on a biological substance known as deoxyribonucleic acid (DNA), which is a double-stranded polymer of nucleotides. A DNA nucleotide is composed of deoxyribose sugar; a phosphate residue; and a purine or pyrimidine base.Purines: adenine (A) and guanine (G)Each purine contains 2 carbon-nitrogen ringsPyrimidines: cytosine (C) and thymine (T)Each pyrimidine contains 1 carbon-nitrogen ring

Each nucleotide consists of a phosphate, a 5-carbon sugar, and a nitrogen-containing base (pyrimidine or purine). As demonstrated in the picture below, phosphate is represented by an orange P in a circle, the sugar is represented by "HO 3'", and the nitrogen base is represented by the beginning letter of the pyrimidine or purine. DNA strands run anti-parallel to each other with one strand having a 5'-3' direction and one strand having a 3'-5' direction. The direction of a strand is determined by what is found at the end. A strand ending with a phosphate is the 5' end and a strand ending with a hydroxyl (HO) group is the 3' end (shown in the picture below). Bases bind to each other in a complementary fashion with adenine only binding to thymine or uracil and guanine only binding to cytosine. Complementary bases link by hydrogen bonds to create the DNA double helix. The process of complementary single strands of DNA forming double stranded DNA is called hybridization or annealing. Hybridization can also be performed between a strand of DNA and a strand of RNA. DNA strands are always replicated in the same direction: 5' to 3'. The 5' phosphate ends attach to the 3' HO ends creating a phosphodiester bond. These bonds are what create the sugar-phosphate backbone to both DNA and RNA. By looking at the picture one can see the solid backbone created by the attachment of the phosphates (indicated by the orange circles).

Fructose makes up 99% of the reducing sugar present in semen. This sugar is produced in the seminal vesicles and its absence may indicate an obstruction proximal to these glands. Although a fructose test is NOT part of a routine semen analysis, the clinician may want to measure this in cases of azoospermia. In azoospermia secondary to obstruction of the ejaculatory ducts or absence of the vas deferens, fructose is usually absent. When azoospermia is caused by failure of the testes to produce sperm, fructose is present. Measuring fructose levels can thus help the clinician determine the cause of azoospermia, although measurement of pH is often more useful in this regard. The procedure for determining the amount of fructose in semen involves heating semen in a strong acid in the presence of resorcinol. Fructose gives a red color to this solution when present.

The results of the Clinitest are abnormal, but can be reported. Because this specimen was from a child, the Clinitest was performed routinely even though not indicated by the results of the Multistix. Due to the fact that the Multistix is specific for glucose and was negative, therefore a non-glucose reducing substance is present. Further confirmatory testing such as thin-layered chromatography is needed for identification of the non-glucose reducing sugar.