Serum dialysis

The objective is to describe a new non-enzymatic urea sensor based on catalytic chemical reaction. The sensor consists of screen-printed transducer (IVA, Ekaterinburg, Russia) and catalytic system which is immobilized on the transducer surface as a mixture with carbon ink. The sensor is used for measuring concentration of urea in blood serum, dialysis liquid. Detection limit is 0.007 mM, while the correlation coefficient is 0.99. Some analysis data of serum samples using the proposed sensor and urease-containing sensor (Vitros BUN/UREA Slide, Johnson Johnson Clinical Diagnostics, Inc.) are presented. 

Mix 0.1ml of the sample (model solution, blood serum, dialysis liquid) with 0.9 ml of 0.9% NaCl. 

Wilhelm M, Ohnesorge FK. 1990. Influence of storage conditions on aluminum concentrations in serum, dialysis fluid, urine, and tap water. J Anal Toxicol 14 206-210. 

Directions are provided for constructing and characterizing an ammonium ion-selective electrode. The electrode is then modified to respond to urea by adding a few milligrams of urease and covering with a section of dialysis membrane. Directions for determining urea in serum also are provided. 

The affinity and cross-reactivity of the whole serum and Fab fragments were determined using equilibrium dialysis for the affinity determination and RIA for the cross-reactivity studies. The average intrinsic affinity constant (Ko) of the antibody (Nisonoff and Pressman 1958) changed very little throughout the... 

All patients with major patterns are monitored for rhabdomyolysis and renal failure. An early sign of rhabdomyolysis is an elevated serum uric acid, associated with an increase in serum CK. Within 8 to 12 hours, the serum tests are repeated. If the uric acid falls and the CK rises, rhabdomyolysis is likely. Renal function tests may also be increased at this time. When the diagnosis of rhabdomyolysis is made, the patient is treated with 40 mg furose-mide IV once, and IV fluids. Urine myoglobin concentrations are obtained. If the patient develops renal failure, hemodialysis or peritoneal dialysis may be necessary. In all cases, multiple drug intoxication, trauma, and rhabdomyolysis are ruled out or treated. All patients are kept under observation until they are asymptomatic. 

Patients with acute hyperkalemia usually require other therapies to manage hyperkalemia until dialysis can be initiated. Patients who present with cardiac abnormalities caused by hyperkalemia should receive calcium gluconate or chloride (1 g intravenously) to reverse the cardiac effects. Temporary measures can be employed to shift extracellular potassium into the intracellular compartment to stabilize cellular membrane effects of excessive serum potassium levels. Such measures include the use of regular insulin (5 to 10 units intravenously) and dextrose (5% to 50% intravenously), or nebulized albuterol (10 to 20 mg). Sodium bicarbonate should not be used to shift extracellular potassium intracellularly in patients with CKD unless severe metabolic acidosis (pH less than 7.2) is present. These measures will decrease serum potassium levels within 30 to 60 minutes after treatment, but potassium must still be removed from the body. Shifting potassium to the intracellular compartment, however, decreases potassium removal by dialysis. Often, multiple dialysis sessions are required to remove potassium that is redistributed from the intracellular space back into the serum. 

The cause of pruritus is unknown, although several mechanisms have been proposed. Vitamin A is known to accumulate in the skin and serum of patients with CKD, but a definite correlation with pruritus has not been established. Histamine may also play a role in the development of pruritus, which may be linked to mast cell proliferation in patients receiving hemodialysis. Hyperparathyroidism has also been suggested as a contributor to pruritus, despite the fact that serum PTH levels do not correlate with itching. Accumulation of divalent ions, specifically magnesium and aluminum, may also play a role in pruritus in patients with CKD. Other theories that have been proposed include inadequate dialysis, dry skin, peripheral neuropathy, and opiate accumulation.43... 

Initiation of dialysis is dependent on the patient s clinical status. Symptoms that may indicate the need for dialysis include persistent anorexia, nausea, vomiting, fatigue, and pruritus. Other criteria that indicate the need for dialysis include declining nutritional status, declining serum albumin levels, uncontrolled hypertension, and volume overload, which may manifest as chronic heart failure, and electrolyte abnormalities, particularly hyperkalemia. Blood urea nitrogen (BUN) and serum creatinine (SCr) levels may be used as a... 

Although EPO deficiency is the primary cause of CKD anemia, iron deficiency is often present, and it is essential to assess and monitor the CKD patient s iron status (NKF-K/DOQI guidelines). Iron stores in patients with CKD should be maintained so that transferrin saturation (TSAT) is greater than 20% and serum ferritin is greater than 100 ng/mL (100 mcg/L or 225 pmol/L). If iron stores are not maintained appropriately, epoetin or darbepoetin will not be effective, and most CKD patients will require iron supplementation. Oral iron therapy can be used, but it is often ineffective, particularly in CKD patients on dialysis. Therefore, intravenous iron therapy is used extensively in these patients. Details of the pharmacology, pharmacokinetics, adverse effects, interactions, dose, and administration of erythropoietin and iron products have been discussed previously. 

J5. Jaume, J. C., Mendel, C. M Frost, P. H., Greenspan, F. S and Laughton, C. W., Extremely low doses of heparin release lipase activity into plasma and can thereby cause artifactual elevations in serum free thyroxine concentration as measured by equilibrium dialysis. Thyroid 6, 79-84 (1996). 

Surks, M. I., Hupart, K. H., Pan, C., and Shapiro, L. E., Normal free thyroxine in critical non-thyroidal illnesses measured by ultrafiltration of undiluted serum and equilibrium dialysis. J. Clin. Endocrinol. Metab. 67, 1031-1039 (1988). 

Y. Ogasawara, K. Ishii, T. Togawa, and S. Tanabe, Determination of sulfur in serum by gas dialysis/high performance liquid chromatography. Anal. Biochem. 215,13—IS (1993). 

Treatment of hyperkalemia depends on the desired rapidity and degree of lowering (Fig. 78-4, Table 78-6). Dialysis is the most rapid way to lower serum potassium concentration. 

Other workers have determined zinc in serum by direct dilution 87> 88). McPherson and George 89) determined total copper and zinc of red cells and the free copper and zinc of plasma and dialysis fluids of patients undergoing regular hemodialysis, using atomic absorption spectroscopy. Spry and Piper 90) determined zinc in whole blood and plasma in blood cells of iron deficient rats. The zinc concentrations were raised in the iron deficient rats. 

The first fractionation of urinary ampholytes in this way was carried out by Boulanger et al. (BIO) in 1952 with the use of ion-exchange resins. They had designed this procedure previously for the fractionation of ampholytes in blood serum (B8). According to this method, deproteinized urine was subjected to a double initial procedure aiming at the separation of low-molecular weight substances from macro-molecular ones. One of the methods consisted of the fractionation of urinary constituents by means of dialysis, the second was based on the selective precipitation of urinary ampholytes with cadmium hydroxide, which, as had previously been demonstrated, permits separation of the bulk of amino acids from polypeptides precipitated under these circumstances. Three fractions, i.e., the undialyzable part of urine, the dialyzed fraction, and the so-called cadmium precipitate were analyzed subsequently. 

A cross-jS spine model was proposed for the fibril structure of human /]2-microglobulin (h/]2m) (Ivanova et al., 2004). h/I2m is a 99-amino acid serum protein with a 7-stranded /(-sandwich fold (Fig. 10A Saper et al, 1991). In patients on long-term kidney dialysis, the protein is deposited as amyloid fibrils in the joints (Floege and Ehlerding, 1996 Koch, 1992). In vitro-formed fibrils of h/)2m give a cross-/] X-ray diffraction pattern (Ivanova et al., 2004 Smith et al., 200S). Several studies have shown that segments of h/]2m form amyloid-like fibrils on their own (Ivanova et al., 2003 Jones et al., 2003 Kozhukh et al, 2002). 

The chilled azide solution is added slowly, dropwise with constant vigorous stirring into a solution of bovine-serum albumin. The pH is maintained at 8.0 to 8.7 by the careful addition of NaOH solution. The resulting pale-yellow solution is kept at 4°C for a duration of 36 hours and then dialysed against trimethamine buffer. After further dialysis for two days against distilled water, the immunogen is isolated by lyophilization. 

M34. Murphy, B. G., McNamee, P., Duly, E., Henry, W., Archbold, P., and Trinick, T., Increased serum apolipoprotein(a) in patients with chronic renal failure treated with continuous ambulatory peritoneal dialysis. Atherosclerosis (Shannon, Irel.) 93, 53-57 (1992). 

Vinyl alcohol copolymer gel is hydrophilic and has been developed for aqueous-phase size-exclusion liquid chromatography however, it is less polar than the polysaccharides. Its specificity permits the direct injection of a biological sample without deproteinization. For example, blood serum from a patient suffering from chronic nephritis has been injected directly as a measure of the degree of dialysis (Figure 3.17). Adenosine triphosphate, adenosine diphosphate, and adenosine monophosphate in red blood cells have also been separated directly (Figure 3.18). Theophylline in blood serum has been... 

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