Donald S. Young

Method for the automatic determination of serum iron

A simple method is described for the automated determination of serum iron and tota iron-binding capacity, which eliminates the need to render apparatus or reagents iron-free. The method is faster than normal procedures and its accuracy is comparable with other accepted methods for the determination of serum iron.

Self-monitoring of blood glucose

your blood glucose levels? Diabetes is a complex condition that differs from patient to patient. It is important that you monitor your glucose levels regularly and get familiar with your pattern of readings at different times of the day. Regular self-monitoring provides valuable information that your health care team can use to make decisions about medication and insulin and improve control of your diabetes. Monitoring your blood glucose also helps prevent immediate problems that can result from glucose levels that are too high (hyperglycemia) or too low (hypoglycemia). Both conditions can be serious if not treated right away.

A Comparison of the Frequency of Hepatitis-B Antigen and Antibody in Hospital and Nonhospital Personnel

Abstract The frequency of hepatitis B antigen and antibody among health-care personnel was compared with that among matched controls with no exposure to patients or blood products. The frequency of the antigen in personnel and controls did not differ significantly. However, the causes may have been different, the antigen correlating with past transfusion in the controls but not in personnel. A history of past hepatitis did not correlate with antigenemia in either population, impugning the validity of hepatitis history as a cause for donor exclusion. Antibody was twice as frequent in health personnel, indicating increased exposure to the antigen; antibody correlated with past hepatitis in personnel, but not in controls, suggesting that overt hepatitis B infection is more common among health personnel. The frequency of hepatitis B antigen among health workers is not currently alarming, but the risk that each antigen-positive health worker represents to his patients remains unknown. (N Engl J Med 289:647–651...

Evaluation of the hexokinase-glucose-6-phosphate dehydrogenase method of determination of glucose in urine.

Abstract The two-step enzymic method for determination of glucose, using hexokinase for phosphorylation of the glucose and glucose-6-phosphate dehydrogenase for the subsequent reduction of triphosphopyridine nucleotide to its reduced form measurable at 340 nm, was evaluated for its suitability for urine analysis. The glucose oxidase method, previously considered the best available, is subject to serious interference which cannot be removed without destroying the accuracy of the method. The hexokinase/G6PD method is highly specific and interference-free. The only possible urinary interference that could be found is a diminution of the glucose indication in the presence of extremely abnormal fructose concentrations. The method was tested for recovery on 100 clinical urine samples. A normal range of 0 to 20 mg 100 ml glucose was indicated by these samples. The method may also be used for blood analysis as normal concentrations of preservative did not interfere. The general analytical and kinetic characteristics of the method were examined, showing that the method may be used accurately at ambient temperatures, with a straight line standard curve, at an incubation time of 10 min, for sample concentrations up to 100 mg 100 ml . The method may be used for screening purposes without determining the background ultraviolet absorbance of the sample.

An inherited defect affecting the tricarboxylic acid cycle in a patient with congenital lactic acidosis

Cultured skin fibroblasts from a 3 yr old girl with severe, diffuse neurologic disease and persistant lactic acidosis, oxidized radioactive citrate, palmitate, and pyruvate at less than one-third the rate of control cells. Her fibroblasts oxidized isocitrate and glutamate at rates comparable with controls. In disrupted cells from this patient, the activity of aconitate hydratase appeared normal. The binding of citrate to aconitate hydratase and the activities of the NAD- and NADP-linked isocitrate dehydrogenases were also normal, while the activity of citrate synthase was slightly below control values. A significant defect was, however, apparent in the activity of the pyruvate dehydrogenase complex although not in the thiamine-dependent first enzyme of that complex. This patient appears to have a partial genetic defect affecting the tricarboxylic acid cycle.

Abnormal blood constituents in acute renal failure

Abstract Three patients with acute renal failure and one patient with normal renal function were dialysed on the artificial kidney. The dialysates were examined for the presence of phenolic acids. Many phenolic acids were identified which are normal constituents of urine together with several phenolic acids of the 2-hydroxy series which are not normally present in urine. Although the patients were on a protein-free regime, several compounds were found which had previously been believed to be of dietary origin. The probable metabolic pathways involved are discussed.

Improved method for the automatic determination of serum inorganic phosphate.

The methods currently available for the automated determination of phosphate suffer from technical disadvantages. The Fiske and Subbarow (1925) method, which is the basis of the Technicon N method, is relatively insensitive and requires the use of a concentrated mineral acid and a heating bath. None of the three methods recently published by Baginski, Epstein, and Zak (1964) avoid the possibility of contamination of one specimen by another. All three methods were designed for a rate of analysis of40 specimens per hour. Two require incubation of reagents at 95°C. while the third involves the use of a 7-foot time-delay coil. Delsal and Manhouri (1958) described a method for the determination of inorganic phosphate which they claimed was 3-5 times more sensitive than the Fiske and Subbarow procedure. This method has now been adapted to the AutoAnalyzer (Technicon Instruments Company, Ltd.) and can be used to make 60 determinations per hour, with very little contamination of one specimen by another.

Blood transfusion costs by diagnosis-related groupsin 60 university hospitals in 1995

BACKGROUND: Transfusion services are frequently challenged to initiate efforts to reduce blood transfusion costs. One approach is to analyze blood transfusion costs for individual medical and surgical Diagnosis‐Related Groups (DRGs). Rank ordering of DRGs by transfusion costs and interinstitutional comparisons of these costs may lead to the selection of DRGs for further analysis of the process of blood transfusion.

Previously Undetected Metabolic Syndromes and Infectious Diseases Among Psychiatric Inpatients

OBJECTIVE This study identified previously undetected metabolic and infectious disease among persons with serious mental illness who were admitted to psychiatric inpatient units. METHODS Observational-naturalistic methods were used to simulate universal screening in order to document evidence of undetected disease among 588 adult psychiatric patients. Data were obtained from medical records and laboratory tests. RESULTS Laboratory results showed that 10% of patients had HIV, 32% had hepatitis B, and 21% had hepatitis C. Glucose levels were elevated in 7%, and total cholesterol levels were elevated in 22%. Nearly 60% had body mass indices above 25. The treatment team missed a considerable proportion of infectious disease (95% of hepatitis B cases, 50% of hepatitis C cases, and 21% of HIV cases) and metabolic disorders (89% of cases with elevated total cholesterol levels and 97% of cases with elevated triglyceride levels). By contrast, only 18% of cases with elevated glucose levels were missed. CONCLUSIONS This study demonstrated very high prevalence of both metabolic disorders and infectious diseases in a psychiatric inpatient population.

Clinical applications of two-dimensional electrophoresis

Two-dimensional electrophoresis is increasingly being used as an important tool for biological research although it continues to have few direct clinical applications. In the absence of simple systems to identify and quantify individual proteins or groups of proteins it is unlikely that clinical applications will increase. Measurement of some individual proteins, for example a single acute phase reactant, often yields as much clinically useful information as could be currently expected from quantitation of several proteins with the same physiological role. Cost-containment pressures within the clinical laboratory will prevent the technique from becoming widely used in the clinical laboratory until it can clearly demonstrate that it can produce clinically important and necessary information that can not be obtained by other means. We continue to believe that the techniques greatest potential lies in identifying a protein or proteins whose concentration can be correlated with a disease and whose concentration varies with the progress of the disease. Antibodies to such proteins can then be produced and used to quantify the disease-associated proteins by a simple procedure, such as nephelometry. In spite of our belief of the likely clinical application of the technique there appears to be no systematic use of two-dimensional electrophoresis for this purpose. With clinical specimens a few investigators still run gels of serum or urine from patients with apparently unusual disorders and compare them visually with gels from healthy individuals. Nevertheless, the technique continues to have considerable unmet promise for clinical applications.