bluuebunny/crossref_metadata_2025 huggingface dataset:
Absence of Measurable Leukocyte Alkaline Phosphatase Activity from Leukocytes of Patients with Chronic Granulocytic Leukemia
Authors: DeChatelet Lawrence R , Cooper M Robert , McCall Charles E
Published: January 2020

Leukocyte phosphatase activity was determined over a broad pH range. Using this procedure, we found no alkaline phosphatase activity in leukocytes from three patients with chronic granulocytic leukemia. The low values usually reported for this disease are actually attributable to acid phosphatase activity, which is slight but measurable at alkaline pH.
Comparison of Serum Calcium Measurements Obtained with the SMA 12/60 and by Atomic Absorption Spectrophotometry
Authors: Gambino S Raymond , Fonseca Ivelice
Published: January 2020

Comparable results are obtained when serum calcium is measured by a colorimetric cresolpthalein method on the Technicon SMA 12/60 and by atomic absorption spectrophotometry (Instrumentation Laboratory Model 153 instrument), with strontium as an internal standard. Sera from 250 patients with abnormal calcium concentrations, ranging from 4.9 mg/100 ml to 9.0 mg/100 ml, were measured by each method; the difference between the means for each method was only 0.04 mg/100 ml. The standard deviation of the difference between paired results was ±0.16 mg/100 ml. We were unable to discover any effect of drug or disease on the colorimetric assay, which therefore is suitable for use in large-scale surveys. On the other hand, the more precise atomic absorption spectrophotometry is suitable for use as a reference method. In addition, with an internal standard it is fast and simple, making it suitable for emergency assays of calcium 24 h a day.
An Initial Reaction Rate Assay for "Glycerate Dehydrogenase"
Authors: McQueen M J , King J
Published: January 2020

Concentrations of substrate, coenzyme, and hydrogen ion, optimal for the reduction of hydroxypyruvate at 37°C by normal and pathological human sera are described. We confirmed, by using the supernatant fluid from homogenized human heart and liver tissue, that the faster-moving isoenzymes have a greater affinity for substrate and coenzyme than the slowermoving isoenzymes, which require higher concentrations for saturation. LDHx, present in human seminal plasma, appears to have the lowest Michaelis constant for hydroxypyruvate. Glycerate dehydrogenase was found to be stable if the standard assay temperature was increased from 25° to 37°C.
A Clinically Useful Method for Determining Erythrocyte Sodium and Potassium
Authors: Helbock Harold J , Brown David M
Published: January 2020

A method is presented for determining erythrocyte sodium and potassium concentration. Heparinized whole blood is separated into cellular and plasma fractions in large-bore capillary tubes. An aliquot of the erythrocyte fraction is then pipetted directly into lithium chloride diluent and the electrolytes determined flame photometrically. Plasma trapping is measured with 14C-inulin and corrections calculated for trapped sodium and potassium. This technique is rapid, simple, and can be performed as a routine procedure by most clinical laboratories.
Comparison of Two Methods for Determining Amylase Activity in Serum and Urine
Authors: Chung Kim Y , Sinha Ram M , Trew J Allan
Published: January 2020

Two methods for estimating amylase activity in serum and urine are compared. A method that uses a chromogenic substrate in a kit was shown to be preferable over the older amyloclastic procedure, which uses starch substrates. The precision of both methods was determined.
Measurement of Lead in Biological Materials by Combined Anion-Exchange Chromatography and Atomic Absorption Spectrophotometry
Authors: Lyons Harold , Quinn F E
Published: January 2020

A method for determination of lead in blood, urine, and tissue is presented. This procedure combines the selective concentration of lead by, and the elimination of large quantities of alkali metals on, an anion-exchange resin with the speed and accuracy of determination by atomic absorption spectrophotometry.
Serum Cholinesterase Variants: Examination of Several Differential Inhibitors, Salts, and Buffers Used to Measure Enzyme Activity
Authors: Garry Philip J
Published: January 2020

Dibucaine, used as a differential inhibitor with acetyl-, propionyl-, and butyrylthiocholine as substrate, clearly identified the "usual" and "atypical" serum cholinesterases. Succinylcholine was also used successfully as a differential inhibitor with butyrylthiocholine as substrate. Sodium fluoride, used as a differential inhibitor, gave conflicting results, depending on whether Tris or phosphate buffer was used in the assay. Mono- and divalent cations (NaCl, KCl, MgCl2, CaCl2, and BaCl2) activated the "usual" and inhibited the "atypical" enzyme at low concentrations. The "usual" enzyme had the same activity in 0.05 mol of Tris or phosphate buffer per liter, while the heterozygous and "atypical" enzymes showed 12 and 42% inhibition, respectively, when assayed in the phosphate buffer. Kinetic studies showed the phosphate acted as a competitive inhibitor of "atypical" enzyme. Km values, determined for "usual" and "atypical" enzymes, were 0.057 and 0.226 mmol/liter, respectively, with butyrylthiocholine as substrate.
Effect of Triton X-100 on Electrophoretic Mobility of Red Blood Cell Ghosts from Normal Individuals and Patients With Tay—Sachs Disease
Authors: Pourfar M , Levy S
Published: January 2020

The negative surface charge of red blood cell ghosts and their anodal electrophoretic migration are largely due to their sialic acid moiety. The RBC of patients with Tay—Sachs disease are thought to contain increased amounts of sialic acid. Electrophoretic mobility and ganglioside content of RBC ghosts were compared in four patients with Tay—Sachs disease and eight normal controls. There was no measurable difference in electrophoretic mobility on cellulose acetate or acrylamide gel. The sialic acid content of lyophilized RBC ghosts was about the same for samples from both patients and controls. The nonionic detergent, Triton X-100, interacts with the ghost glycolipoprotein, causing a reversal of migration, both on cellulose acetate and moving-boundary electrophoresis. Acrylamide gel, by its sieving effect, disrupts the complex, which then migrates anodally again.
Automated Flame Photometry of Serum Sodium and Potassium
Authors: Pennacchia Gina , Bethune Victor G , Fleisher Martin , Schwartz Morton K
Published: January 2020

A simple, rapid, automated procedure for flame photometry is described for use with the IL flame photometer and on-line dilutor and Technicon Sampler II.
Manual Colorimetric Methods for Pseudocholinesterase and Red Cell (True) Cholinesterase
Authors: MacQueen J , Plaut D , Borges J , Anido G
Published: January 2020

This report describes both an improved version of Garry and Routh’s colorimetric assay for serum pseudocholinesterase [Clin. Chem. 11, 91 (1965)] and a variation of this method for use in measuring cholinesterase in red cells. These procedures require either 0.1 ml of serum (diluted 10-fold) cr 0.1 ml of packed, heparinized erythrocytes (diluted 100-fold). The reaction involves the hydrolysis of acetylthiocholine to acetic acid and thiocholine, and the quantitation of the thiocholine with 5,5'-dithiobis-2-nitrobenzoic acid. In the procedure, the sample of diluted serum or cells is added to the combined buffer—color-substrate reagent at 37°C. After incubation for 10 min, quinidine sulfate is added to retard the reaction and the color is read at 450 nm. Blanks are required with each red cell sample, but not for sera. The results correlate well with those obtained by Michel’s standard ΔpH assay, Kalow’s benzoylcholine uv-rate reaction, Caraway’s colorimetric procedure, and Ellman’s colorimetric rate reaction. A method for determination of dibucaine-inhibited serum pseudocholinesterase is also described.
Detection of Phenylketonuric Heterozygotes
Authors: Jackson Sanford H , Hanley William B , Gero Terese , Gosse G D
Published: January 2020

Estimation of plasma phenylalanine and tyrosine by an abridged (30 min) column chromatography procedure was assessed. Plasma phenylalanine and tyrosine concentrations, determined in 112 phenylketonuric obligate heterozygotes and in 88 normal controls, did not differ significantly from other reported series in which the data were obtained by column chromatography. All these series were combined and analyzed statistically. Phenylketonuric heterozygotes can be detected with a high degree of discrimination by the ratio of phenylalanine to tyrosine in the plasma of the fasting subject, in combination with the plasma phenylalanine concentration.
Increased AutoAnalyzer Dialysis of Calcium and Magnesium in Presence of Protein
Authors: Lott John A , Herman Thomas S
Published: January 2020

We have studied calcium and magnesium determination with the AutoAnalyzer, using dialysis, and measurement by atomic absorption spectrophotometry. The fraction of calcium and magnesium that dialyzes is proportional to the protein content of the sample; therefore an error is introduced when aqueous solutions of calcium or magnesium salts are used as standards. Apparently, the presence of proteins causes increased dialysis of Ca+2 and Mg+2.
Use of an Anion-Exchange Column to Determine Serum Iron-Binding Capacity
Authors: Lehmann H Peter , Kaplan Alex
Published: January 2020

A rapid procedure is described for determining total iron-binding capacity (TIBC) by use of a small, disposable resin column. Serum is saturated with excess ferric citrate, and iron not bound to protein is then removed by passing the mixture through the column of anion-exchanger. Transferrin-bound iron in the effluent, the TIBC, is determined colorimetrically (AutoAnalyzer), with 2,4,6-tripyridyl-1,3,5-triazine as color reagent. The percentage saturation with iron may be obtained from colorimetric measurement of original serum iron and the TIBC, or by radioactive counting if 59Fe is incorporated in the ferric citrate used to saturate the serum. Our method is compared with the MgCO3 precipitation technique for the removal of excess iron after saturation and to an ultrafiltration technique in which protein-bound iron is retained by a membrane and the filtrate analyzed for unbound iron, thus obviating absorbents in the determination of TIBC. Results from the resin-column and ultrafiltration procedures correlated well, whereas those from the MgCO3 method were consistently lower and more erratic.
Sephadex Adsorption of Bilirubin from Neonatal and Adult Serum
Authors: Kapitulnik J , Blondheim S H , Kaufmann N A
Published: January 2020

The bilirubin (BR)-binding capacity of albumin in serum from cord blood, as estimated by Sephadex gel filtration, is less than that of adult serum. The binding site at which BR is tightly bound by albumin in pools of infant serum was saturated at an average BR/albumin molar ratio of 0.66, while in adult serum the ratio was 1.00. With further increase in BR concentration, albumin of infant serum bound BR less than that of adult serum. These findings appear to have clinical significance with respect to the danger of BR encephalopathy in icteric infants.
Column-Chromatographic Analysis of Naturally Fluorescing Compounds: II. Rapid Analysis of Indoleacetic Acid and 5-Hydroxyindoleacetic Acid in Biological Samples
Authors: Chilcote D D
Published: January 2020

A previously described [Clin. Chem. 18, 778( 1972)] chromatographic separation and fluorometric system has been adapted to determination of 5-hydroxyindole-3-acetic acid and indole-3-acetic acid in body fluids and biological extracts. A strong anion-exchange resin, "Aminex A-27," is used. The indoleacetic acids are eluted at 60°C with a single ammonium acetate-acetic acid buffer. No gradient programming or post-column reaction designed to enhance the fluorescence of the desired compounds is necessary. The sensitivity of the detector allows analysis of 100 ng of each acid in the sample loaded onto the column.
Quantitation of Plasma Aldosterone by Radioimmunoassay
Authors: Cyr M J St , Sancho J M , Melby J C
Published: January 2020

Aldosterone antibodies were produced by injecting sheep with the albumin conjugate of aldosterone-18,21-dihemisuccinate. Conditions optimal for an accurate, reproducible assay with this antiserum were determined experimentally. Aldosterone is extracted from plasma and isolated by a single thin-layer chromatographic system before the immunoassay is performed. Normal plasma aldosterone in supine subjects is 8.6 ± 3.8 ng/100 ml; after 2 h in the upright position, 18.3 ± 9.5 ng/100 ml. Eighteen months of experience with the method have proved it to be reliable with respect to reproducibility, accuracy, and precision.
Partial Correlation of Some Blood Constituents
Authors: Roberts L B
Published: January 2020

Although it is well known that the concentrations of some blood constituents are significantly correlated with the subject's age, little is known about the relationships existing between the constituents themselves. This report examines correlations between some blood constituents apart from the effect of age. The possible meaning of some of these correlations is discussed.
63Ni Complexes in Rabbit Serum and Urine after Injection of 63NiCl2
Authors: Van Soestbergen Maria , Sunderman F William
Published: January 2020

Radioactive nickel chloride (63NiCl2) was injected i.v. into rabbits in dosage of 0.24 mg Ni/kg body wt. 63Ni was rapidly cleared from the serum (T1/2 ≃ 8.2 h) during the period from 1 h to 2 days after the injection, but slowly (T1/2 ≃ 95 h) during the period from 4 to 7 days after the injection. During 24 h after injection of 63NiCl2, an average of 90% of serum 63Ni was bound to albumin and 10% was ultrafiltrable. Chromatography on Sephadex G-25 demonstrated the presence of five distinct 63Ni complexes (Fractions I to V) in serum ultrafiltrates. During 24 h after injection of 63NiCl2, an average of 78% of the administered dose of 63Ni was excreted in the urine. Chromatography of the urine on Sephadex G-25 separated three 63Ni complexes, which appeared to have identical chromatographic mobilities as serum Fractions II, III, and V. The chemical identities of the ultrafiltrable 63Ni complexes in serum and urine have not been established, although one (Fraction V) resembles Ni histidine in its chromatographic mobility on Sephadex G-25. This study demonstrates that ultrafiltrable nickel in serum and urine does not exist primarily as free Ni(II), but instead as Ni complexes, and suggests that ultrafiltrable Ni receptors play an important physiological role in nickel homeostasis by serving as diffusible vehicles for the extracellular transport and renal excretion of nickel.
Estimation of Serum Proteins by Electrophoresis on Cellulose Acetate
Authors: Keyser J W , Watkins G L
Published: January 2020

We have evaluated results for albumin obtained by a standard procedure for cellulose acetate electrophoresis of proteins in serum. The Ponceau S-stained albumin and globulins were eluted and the albumin was calculated by the generally accepted formula [(albumin-bound dye absorbance/absorbance of total protein-bound dye) x total serum protein concn] and by the formula (absorbance of albumin-bound dye in test/absorbance of albumin-bound dye in a reference serum) x concn of albumin in reference serum. The ratio of values by the first and second methods ranged from 0.93 to 1.30, the first giving the higher results in cases of discrepancy. These findings confirm the limitations in accurately calculating any serum-protein fraction by the first method. The second method appears to be the more accurate.
A Study of Various Electrophoretic and Inhibition Techniques for Separating Serum Alkaline Phosphatase Isoenzymes
Authors: Johnson Roy B , Ellingboe Karen , Gibbs Phyllis
Published: January 2020

Optimal conditions for the identification and semiquantitation of the isoenzymes of serum alkaline phosphatase are reviewed and a new technique is presented. In the recommended scheme, specific disc electrophoretic conditions are used to produce good separations, which are improved by comparing the alkaline phosphatase patterns of sera before and after treatment with heat or urea (3 mol/liter). This method is compared with other electrophoretic and inhibition techniques. Interpretation is aided by (a) reference to the relative mobilities of each isozyme, and (b) inactivation of bone alkaline phosphatase by heat or urea. The isozymes originating from bile, intestine, placenta, bone, and liver can be independently resolved as separate bands with untreated sera except when bone alkaline phosphatase is grossly increased. The proposed method permits identification and semiquantitation of all the recognized alkaline phosphatase isozymes in most sera, as an aid to diagnosis.
Prenatal Diagnosis of Genetic Disorders: Trials and Tribulations
Authors: Davidson Ronald G , Rattazzi Mario C
Published: January 2020

Prenatal detection of genetic disorders by amniocentesis in the second trimester of pregnancy, followed by studies of amniotic fluid cells, has added a new dimension to genetic counseling. This paper reviews the technique, indications, results, and complications, with emphasis on the problem of interpretation of results, particularly in the detection of fetuses with metabolic diseases.
Chemical Basis of the Sulfo-phospho-vanillin Reaction for Estimating Total Serum Lipids
Authors: Knight Joseph A , Anderson Shauna , Rawle James M
Published: January 2020

Results with the "sulfo-phospho-vanillin" reaction, much used for determining total serum lipids, have been favorably compared with those for the gravimetric method. We investigated the basic chemistry of the reaction and determined the reactivity of this single reagent with various lipids. Our results suggest that: (a) The reaction requires a carbon-carbon double bond. (b) Concentrated sulfuric acid reacts with unsaturated lipids in the initial step to form a carbonium ion. (c) Phosphoric acid reacts with vanillin to produce a phosphate ester, with a resulting increase in the reactivity of the carbonyl group. (d) The carbonium ion reacts with the carbonyl group of phosphovanillin to form a colored compound, which is stabilized by resonance. (e) Unsaturated compounds with more than one double bond react, but reaction may vary with steric hindrance. (f) The method is reasonably precise, but its accuracy depends primarily on the reference standard used.
Sensitive, Rapid Quantitation of Serum and Urinary Protein by Electroimmunodiffusion
Authors: de Pizzolato M C B , Del Campo G B , Pizzolato M A , Vergani C
Published: January 2020

A simple, rapid method is described for quantitative estimation of albumin, transferrin, and α2-macroglobulin on strips of antibody-spread gelatinized cellulose acetate. Samples are applied on a strip with 1-µl micropipets and a volumetric distributor is used to coat the strip with 2µl of a diluted antiserum per square centimeter. Electrophoresis requires 2 h for albumin and at least 3 h for α2-macroglobulin and transferrin. Precipitate peaks are sharply defined. As little as 10 ng of protein can be estimated, so urinary proteins can be studied without concentrating the sample.
A Study of the Problems of Inactivation of Creatine Kinase in Serum
Authors: Dalal Fram R , Cilley Jonathan , Winsten Seymour
Published: January 2020

Addition of sulfhydryl groups to the reaction mixture, to stabilize serum creatine kinase (creatine phosphokinase, CPK), results in apparent increases in the activity of this enzyme in many sera. In addition, in sera from patients just after myocardial infarction, assays for sulfhydryl-activated CPK have a different clinical pattern than do those for CPK assayed without sulfhydryl activators: activities are greater and remain abnormally high longer in assays in which the enzyme is sulfhydryl activated. If the assay is done without sulfhydryl activators present, technical difficulties appear, because CPK in serum is rapidly inactivated at room temperature. CPK is apparently inactivated in at least two ways. One, which is irreversible, is inhibited by albumin; the other, which is reversible by sulfhydryl groups, seems to result from the presence of substances in the pooled serum used that are both protein bound and free.
Comparison of Results from the Du Pont "ACA" and Technicon "SMA 12/ 60"
Authors: Westgard James O , Lahmeyer Brenda L
Published: January 2020

The Du Pont "Automatic Clinical Analyzer" (ACA) and the Technicon "SMA 12/60" were compared as to precision, range of linearity, and results for sera from patients. Precision of the ACA was equal to or better than that of the SMA 12/60 for all determinations except SGOT in the normal range. The ACA showed a wider range of linearity for BUN, total protein, LDH, alkaline phosphatase, SGOT, and bilirubin, and equal linear ranges for glucose and albumin. Patient’s sera comparisons showed differences for glucose in uremic sera. Albumin values from the ACA did not compare well with those by HABA dye method from the SMA 12/60, but did compare well with values obtained by electrophoresis and by a bromcresol green method adapted to the SMA 12/60. Bilirubin values from the ACA were higher than those from the SMA 12/60. Comparable results were obtained for the enzyme determinations when the SMA 12/60 was calibrated in the same units as the ACA.
Direct Fluorometric Determination of Urea in Urine
Authors: Rho Joon H
Published: January 2020

In this quantitative fluorometric method, diacetylmonoxime is used for the determination of the urea. The products of the reaction of urea with diacetylmonoxime in acid solution exhibit two fluorescence maxima, at 410 and 525 nm. The intensity of the 525 nm maximum is linear over a wide range of urea concentration and the reaction is shown to be practically specific for urinary urea.
Characterization of Electrophoretic Lipoprotein Fractions: Immunochemical and Electron Microscopic Studies
Authors: Werner Mario , Jones Albert L
Published: January 2020

To improve the characterization of electrophoretic lipoprotein subfractions, we developed two new techniques for analyzing lipoproteins after electrophoresis on thin agarose layers. Overlay with antisera exactly localizes specific apoproteins without any distortion caused by antigen diffusion; electron microscopy of eluted fractions determines the varying particle-size distribution. Applied together, these methods can detect individual differences between hyperlipemic samples that are not immediately apparent in the electrophoretic pattern, and should provide valuable new insight into the classification of hyperlipoproteinemias.
Accelerated Single-Column Procedure for Automated Measurement of Amino Acids in Physiological Fluids
Authors: Efron Klara , Wolf Paul L
Published: January 2020

This automated analytical procedure involves a single 27 cm x 0.9 cm column of UR-40 resin and a stepwise elution with sodium citrate buffers. In one sequential run more than 35 acidic, neutral, and basic amino acids can be measured in physiological fluids in 6 h. Thus, a minimum of three runs can be performed per 24 h, during which the analysis can be unattended. Increased sensitivity allows the use of small samples (such as 0.2 ml of plasma ultrafiltrate). Picric, sulfosalicylic, or perchloric acids are not required for sample preparation. Ultrafiltration under nitrogen pressure is used instead and gives a clear solution containing the free amino acids. Ultrafiltration rate is 1 ml per 1.5 h; 10 samples can be processed simultaneously.
Determination of Serum Albumin with the "SMA 12/60" by a Bromcresol Green Dye-Binding Method
Authors: Westgard James O , Poquette Michael A
Published: January 2020

A bromcresol green (BCG) method for serum albumin has been adapted to the Technicon "SMA 12/60." Sensitivity and linearity critically depend on the concentrations of BCG and surfactant ("Brij-35"). With appropriate concentrations, linearity to 6.0 g/dl is achieved. Interaction is 2-3%. Standard deviations for quality control pools of 2.0 and 4.7 g/dl during three months of routine service were 0.06 and 0.11 g/dl. Values agree well with values determined by the Du Pont "ACA" (bias = 0.047 g/dl, SD = 0.191 g/dl, t = 1.746, r = 0.975, n = 53), by a modified Beckman "DSA" method in which BCG is also used (bias = 0.006, SD = 0.164, t = 0.398, r = 0.976, n = 115), and by electrophoresis on cellulose acetate (bias = 0.028, SD = 0.203, t = 1.006, r = 0.961, n = 54). Blank errors for hemolyzed samples (plasma hemoglobin up to 350 mg/dl), icteric samples (bilirubin up to 30 mg/dl), and lipemic samples (triglycerides up to 500 mg/dl) are 0.2 g/dl or less when the blank channel is not used. Normal range is estimated to be 3.5 to 4.8 g/dl (n = 145; 2.5 and 97.5 percentiles).
Separation of Isoenzymes of Alkaline Phosphatase by Substrate—Gel Imprint after Electrophoresis on Cellulose Acetate
Authors: Rhone Douglas P , Mizuno Florence M
Published: January 2020

Isoenzymes of alkaline phosphatase, separated by electrophoresis on cellulose acetate, were developed by a substrate—gel imprint. The gel was prepared in an alkaline buffer and contained β-naphthyl acid phosphate, which was hydrolyzed to β-naphthyl and phosphorus. The β-naphthyl was coupled to the diazonium salt, Fast Violet B, and an insoluble red compound was formed on a cellulose acetate strip to mark the sites of enzyme activity. The electrophoretic mobilities of the isoenzymes were compared with those of serum proteins. Supporting data included thermostability and chemical inhibition (urea and phenylalanine) studies. This method was used to evaluate patterns in tissues and human sera.
Fluorometric Assay of Diphenylhydantoin in Plasma or Whole Blood
Authors: Dill Wesley A , Glazko Anthony J
Published: January 2020

A highly sensitive assay procedure for 5,5-diphenylhydantoin (DPH) involves oxidation with alkaline permanganate to form benzophenone. This is then extracted with heptane, allowed to react with concentrated sulfuric acid, and the fluorescence of the reaction product is measured. The procedure appears to be fairly specific for DPH; 5-(p-hydroxyphenyl)-5-phenylhydantoin (a DPH metabolite), phenobarbital, or other anticonvulsant drugs do not interfere. The sensitivity of the fluorometric procedure permits assays on finger-blood specimens. It provides a simple means for evaluating the effectiveness of a given dose schedule in different subjects.
Countercurrent Chromatographic Separation of Catecholamine Metabolites from Urine
Authors: Hurst Robert E , Ito Yoichiro
Published: January 2020

A continuous-flow method is described for achieving high-resolution separations with liquid-liquid partition without the use of an inert support. The instrument consists of a 60-m coil of Teflon tubing (0.85 mm i.d.) mounted planetarily on a centrifuge arm. The coil is filled with the stationary phase and the mobile phase is pumped through the column in a direction opposing the flow of the stationary phase imposed by centrifugal force. With ethyl acetate as the stationary phase and an aqueous solution of NaCl (5 g/100 ml) and acetic acid (10 ml/100 ml) as the mobile phase, (3-methoxy-4-hydroxyphenyl)-hydroxyacetic acid (VMA) and (3-methoxy-4-hydroxyphenyl)-acetic acid (HVA), the major products of catecholamine metabolism, elute in 2 and 7 h, respectively. With a 280 nm-monitor on the effluent, abnormal amounts of these two compounds can be detected in 1 ml of urine. The fractions containing these compounds were analyzed by both gas—liquid and thin-layer chromatographic methods. HVA is essentially completely separated from other compounds. Although VMA is found with 3-8 other unknown compounds, none interferes with any of the colorimetric assays for VMA. Several abnormal urines from patients with various types of neurosecretory tumors were examined, and a distinctive pattern of urinary excretion of these compounds was seen for each type of case.
Simplified Rapid Electroimmunodiffusion Technique for Measuring α1-Antitrypsin in Serum
Authors: Manildi Ernest R
Published: January 2020

A rapid method is described for immunochemical quantitation of α1-antitrypsin by electroimmunodiffusion on cellulose acetate. Compared to earlier qualitative screening techniques for trypsin activity, including trypsin inhibitory capacity, the procedure presented here is specific, reproducible, and quantitative for α1-antitrypsin. It is inexpensive and less time consuming than electroimmunodiffusion or radial immunodiffusion in agar gel. The test is so simply done that this procedure can be routinely used by most hospital clinical laboratories. The technique is easily adapted to immunochemical quantitation of other protein fractions.
Automated Method for Determining Amylase Activity in Serum and Urine
Authors: Mazzuchin A , Weggel C , Porter C J
Published: January 2020

We describe an automated procedure for determination of α-amylase activity in serum or urine by use of a water-insoluble chromogenic starch substrate (commercially available). "AutoAnalyzer" (Technicon Corp.) equipment is used in which the sample and suspended substrate are introduced simultaneously into the flow system. After incubation at 37 °C the water-soluble blue-starch breakdown products are filtered on-line across a cellulose nitrate membrane. Absorbance is measured at 630 nm, and the α-amylase activity read from a standard curve. The automated procedure has been in use for the past year and has been found to be an operationally simple, reproducible, and reliable method, which can be applied over a wide range of enzyme activity. Results of comparative studies with other α-amylase methods are also described.
Atomic Absorption Spectrometry of Nickel, Copper, Zinc, and Lead in Sweat Collected from Healthy Subjects during Sauna Bathing
Authors: Hohnadel David C , Sunderman F William , Nechay Maria W , McNeely Michael D
Published: January 2020

Ni, Cu, Zn, and Pb were measured by atomic absorption spectrometry in sweat samples obtained by the arm-bag technique from 48 healthy adult subjects (33 ♂, 15 ♀ ) during sauna bathing (15 min at 93 °C, dry heat). The men sweated more profusely than the women (volume, in milliliters, of sweat collected: mean, SD, and range: 23 ± 12 (3-55) and 7 ± 3 (2-13), respectively. The concentrations, in µg/liter, (mean, SD, and range) of trace metals in sweat of men and women, respectively, were: nickel, 52 ± 36 (7-180) and 131 ± 65 (39-270); copper, 550 ± 350 (30-1440) and 1480 ± 610 (590-2280); zinc, 500 ± 480 (130-1460) and 1250 ± 770 (530-2620); and lead, 51 ± 42 (8-184) and 118 ± 72 (49-283). In sweat samples from 11 women on oral contraceptives, concentrations of Ni, Cu, Zn, and Pb did not differ significantly from the values in the 15 control women. Sweating is a demonstrably significant route for excretion of trace metals, and sweating may play a role in trace-metal homeostasis. Essential trace metals could conceivably be depleted during prolonged exposure to heat; conversely, sauna bathing might provide a therapeutic method to increase elimination of toxic trace metals.
Patterns and Clusters—Multivariate Approach for Interpreting Clinical Chemistry Results
Authors: Winkel Per
Published: January 2020

Quantitative assessment of the relationship among clinical observations requires the use of statistical models constructed for this purpose, i.e., multivariate models. Some multivariate methods of pattern cognition are reviewed. A pattern is defined as a combination of laboratory test values simultaneously observed in a patient. A single pattern may be noticed because it is suddenly realized that it is a highly abnormal one. This demonstration requires a multivariate reference region in place of the more commonly used univariate reference intervals. This concept is illustrated by an example in which the multivariate gaussian distribution is used as a model. A group of patterns belonging to a major category of patterns may be delimited, because patterns from this group are in some sense distinct from all other patterns of the category; that is, they form a cluster. Numerical taxonomy comprises the methods by which patterns or symptoms are compared and sorted into groups on the basis of their overall similarity. It is emphasized that many methods for cluster detection are unsound from a theoretical point of view, and if patients are classified the problem of the assignment of weights to variates is still unsolved. It is concluded from a review of the applications that the methods may be useful for the generation of hypotheses but they should not be used as the only methods in the analysis of multivariate data. Additional clustering methods oriented toward one specific goal are reviewed as well.
Factors Contributing to Intra-Individual Variation of Serum Constituents: 1. Within-Day Variation of Serum Constituents in Healthy Subjects
Authors: Statland Bernard E , Winkel Per , Bokelund Henning
Published: January 2020

We evaluated the within-day variation of serum constituents in a group of 11 healthy young men. Twenty-two constituents were assayed at the same time, 19 of them on the " AutoChemist" multi-channel analyzer. The statistical model of analysis-of-variance was used to separate certain factors—subject, time of day, and subject-time interaction— from the analytical variation. The estimate of analytical variation was based on data for duplicate samples of blood which were taken from all subjects at 0800 h, 1100 h, and 1400 h. The following serum constituents varied significantly (P <0.05) as a function of time of day: sodium, potassium, chloride, urea, iron, bilirubin, total lipids, and acid phosphatase.
Automated Fluorometric Method for Screening for Erythrocyte Glucose-6-Phosphate Dehydrogenase Deficiency
Authors: Dickson Larry G , Johnson Carl B , Johnson Donald R
Published: January 2020

Deficiency of the erythrocyte enzyme, glucose-6-phosphate dehydrogenase [EC 1.1.1.49, GPD] is associated with hemolysis after exposure to oxidative drugs, ingestion of the fava bean, or infection. Episodes of hemolysis may be prevented by avoiding ingestion of substances toxic to erythrocytes with GPD deficiency. We describe here an automated fluorometric method suitable for screening for erythrocyte GPD deficiency. Anticoagulated whole blood is examined. Reliable results are obtained for hemoglobin concentrations ranging from 7-17 g/100 ml.
Interpretation of Hyperamylasemia in Diabetic Coma
Authors: Belfiore Francesco , Napoli Elena
Published: January 2020

In sera of patients with diabetic coma, amylase activity was markedly elevated and closely correlated with the activity of some lysosomal enzymes, including β-glucuronidase, N-acetyl-β-glucosaminidase, and acid phosphatase. All these enzyme activities returned to normal with the normalization of glycemia. Activities of serum lipase, aspartate and alanine aminotransferases, aldolase, and lactate dehydrogenase were not changed. Since liver amylase, although primarily contained in microsomes, shows "latency" and is activated by several agents as are lysosomal enzymes, these findings might be regarded as a further evidence of a similarity between amylase and lysosomal enzymes, and make probable the hypothesis that a process of "activation" occurring in liver might be the cause of increased amylase activity in serum as well as of lysosomal enzymes.
Colorimetric Microdetermination of Free Fatty Acids
Authors: Soloni Felix G , Sardina Laura C
Published: January 2020

A colorimetric method for determination of free fatty acids has been developed, based on the estimation of copper in a chloroform extract of their cupric salts with oxalic acid bis-(cyclohexylidenehydrazide). Contamination with inorganic copper during extraction is practically eliminated by using filter-paper pads. Specificity and interferences are discussed. Recoveries average 101.1%. Normal values are 10.0 ± 8.2 mg/dl (0.390 ± 0.320 mmol/liter), with no statistically significant sex-related difference. Correlation with the reference method of Dole and Meinertz [J. Biol. Chem. 235, 2595 (1960)] is 0.954. Ten samples can be measured in about 45 min.
Serum Enzymes in Diabetes Mellitus
Authors: Belfiore Francesco , Vecchio Luigi Lo , Napoli Elena
Published: January 2020

Serum enzymes that show changed activities in diabetes mellitus can be divided into four groups: Group I includes some lysosomal enzymes—β-glucuronidase N-acetyl-β-glucosaminidase, acid phosphatase, and amylase—that show increased activity correlated with blood sugar concentration. Because lysosomal enzymes as well as liver amylase show latency and may be "activated" by several agents, their increased activity in the serum of diabetics might be a manifestation of an activation occurring in tissues. Group II includes alkaline phosphatase and trehalase, which are increased but not correlated with blood sugar concentration. Their enhanced activity may reflect tissue metabolic disorders. Group III includes enzymes that increase in the postketotic period almost regularly—phosphohexose isomerase —or in only the most severe cases—aminotransferases and several dehydrogenases—because of tissue damage caused by metabolic and circulatory alterations. Cholinesterase, on the other hand, is decreased. Group IV includes any of the above-mentioned enzymes, and still others, that may be more active in diabetics with complications such as hepatic and renal involvement and obesity.
A Modified Indirect Method for Determining Erythrocyte Sodium and Potassium Concentrations
Authors: Small Larry L , Coulter Dwight B
Published: January 2020

An automated method was adapted to measure the concentration of Na and K in plasma, nonhemolyzed whole blood, and hemolyzed whole blood, and thus allow the calculation of erythrocyte electrolyte concentrations by a modified indirect method. The Na concentrations of nonhemolyzed whole blood and plasma were used to calculate the percent cell volume (hematocrit) of a blood sample. The percent cell volume and concentrations of Na and K in nonhemolyzed whole blood were used to modify the indirect method of calculating erythrocyte Na and K concentrations in canine, porcine, and human blood samples. Significant differences were found between the two indirect methods (indirect and modified indirect) used to calculate erythrocyte Na and K concentrations of human blood samples.
Stability of Erythrocytic Enzymes for Screening Tests
Authors: Lowe Mei L , Gin Jerry B , Demetriou James A
Published: January 2020

We investigated the stability of certain erythrocytic enzymes as assayed qualitatively by fluorescence spot tests. Preservation of the activities of glucose-6-phosphate dehydrogenase (GPD), pyruvate kinase (PK), triose phosphate isomerase (TPI), glutathione reductase (GTD), and NADH diaphorase (ND) in heparin, glucose—EDTA, or Alsever’s solution was studied at -20°C and 30°C. In Alsever’s solution, GPD, PK, GTD, and TPI are stable for 25 days at 30°C, whereas ND is stable for only 10 days at either -20°C or 30°C. The stabilizing action of Alsever’s solution permits either large population sampling before testing or a sufficient time period for transport of samples to a central laboratory for processing.
Gas-Chromatographic Measurement of Urinary Polyamines in Cancer Patients
Authors: Denton M Drue , Glazer Helen S , Zellner David C , Smith Frank G
Published: January 2020

The polyamines, spermidine and spermine, and the precursor diamine, putrescine, may have an important role in control of cellular growth because of their interaction with nucleic acid structure, function, and synthesis. We have developed a quantitative gas-chromatographic procedure for measuring polyamines and have measured their urinary excretion by cancer patients and noncancerous patients. Marked variations in values obtained during therapy and in response to some other variables are described. Both hydrolyzed and nonhydrolyzed urine samples have been examined, in order to quantitate both total and free polyamine and putrescine excretions. The potential clinical importance of these studies and the application of other instrumentation such as mass spectroscopy to improve the specificity and sensitivity of this method are discussed.
Monitoring Phenylalanine—Tyrosine Metabolism by High-Resolution Liquid Chromatography of Urine
Authors: Mrochek J E , Dinsmore S R , Ohrt D W
Published: January 2020

Urines, selected to demonstrate the utility of the LC system known as the "UV-Analyzer" for simultaneous investigation of a wide range of metabolites, were obtained from Parkinsonian patients being treated with l-DOPA alone or l-DOPA plus α-methyldopahydrazine, a dopa decarboxylase inhibitor. Sulfate conjugates are the major excretion products of those metabolites of l-DOPA retaining the catechol (3,4-dihydroxyphenyl) structure. Administration of the dopa decarboxylase inhibitor considerably decreased urinary excretion of 3,4-dihydroxyphenylacetic and 3,4-dihydroxymandelic acids and increased excretion of 3-methoxy-4-hydroxy-phenyl lactic acid. Urinary chromatograms obtained for several children with neurological disorders manifest by seizures, infantile autism, and mental retardation showed elevated excretion of 4-hydroxyphenylacetic (a metabolite of tyramine) and 4-hydroxyhippuric acids. Two of the more severely affected children excreted a new metabolite, identified by mass spectrometry and gas chromatography—mass spectrometry as α-methoxy-α-(3-methoxy-4-hydroxyphenyl)-acetic acid. This homolog of 3-methoxy-4-hydroxymandelic acid (VMA) was observed also in urine samples from patients with other types of diseases, including chronic lymphocytic leukemia, Lesch— Nyhan syndrome, malignant carcinoid, synovial sarcoma, multiple myeloma, and embryonic neoplasia. Its metabolic precursors are unknown.
Evaluation of the Harleco Apparatus for Determining Carbon Dioxide in Whole Blood
Authors: Strever Bill C , Johnson Carl A , Gadsden Richard H
Published: January 2020

A simplified method for determining the total CO2 content of whole blood is evaluated, and results are compared to those obtained with a "Blood Gas Analyzer" (Instrumentation Laboratories). A high degree of correlation is shown. The described method makes such determinations simple and reliable, especially for emergency use in the laboratory or at bedside.
Electrophoresis of Hemoglobin on Polyacrylamide Gels: Precise Method for Measurement of Hemoglobin A2
Authors: Williard Robert F , Lovell Winfred J , Dreiling Bernard J , Steinberg Martin H
Published: January 2020

Hemoglobin electrophoresis on polyacrylamide gels is a technique applicable in the clinical laboratory that processes moderately large numbers of specimens. Rapid and precise, it yields reproducible quantitative data when the hemoglobins are eluted from the gel and their concentrations determined spectrophotometrically. Hemoglobin A2 measurements were reproducible and did not differ from those measured by column chromatography on DEAE-cellulose. Concentrations of hemoglobin A2 in the blood of patients with sickle cell anemia were significantly higher than in normal individuals and individuals with sickle trait, but significantly lower than is the case for patients with beta-thalassemia minor.
Single Glucose Oxidase—Peroxidase Reagent for Two-Minute Determination of Serum Glucose
Authors: Morin Leo G , Prox Jerome
Published: January 2020

The glucose oxidase—peroxidase procedure for determining glucose in serum or plasma has been modified by changing the assay pH to 5.5, altering the ratio of glucose oxidase to peroxidase, and using a soluble chromogen, p-diphenylamine sulfonate, to prepare a single complete reagent that develops stable color within 2 min without deproteinization. Most interferences were inconsequential. Serum that clearly is icteric or hemolytic is Somogyi-precipitated. Recovery was 99% and the CV was 3.3%. Correlation with results obtained by the neocuproine procedure, with use of the SMA 12/60, averaged 12 mg/dl lower values (r2 = 0.98).
Evaluation and Recalculation of Manufacturer’s Instrument-Specific Aspartate Aminotransferase Values for Reference Sera
Authors: Laessig Ronald H , Indriksons Andris , Schwartz Thomas H , Paskey Toni A
Published: January 2020

We compared a manufacturer’s stated values to those obtained by a reference method for aspartate aminotransferase activity in reference sera. We determined the validity with which this manufacturer’s stated values may be used as multichannel-analyzer set points, and related values obtained by the reference method to instrument-specific values by regression analysis. Data were obtained from 40 multichannel analyzers, comprising three different instruments (and their respective procedures): SMA 12/ 60, ultraviolet and colorimetric; SMA 12/30, colorimetric (reported in Karmen units); and MARK X, colorimetric. Results that best correspond with those for the Karmen-uv reference method are those obtained by automated methods that most closely emulate it. Regression equations relate Karmen (reference method) results to instrument-specific values. These relationships enable laboratories to check assay values of their lots of reference or control sera against a consensus value obtained from the group of similar instruments used in the study. Regression equations are calculated for the intercomparison of results from the four automated procedures.
RIoT: A Routing Protocol for the Internet of Things†
Authors: Omer Farooq Muhammad
Published: January 2020

The routing protocol for low-power and lossy networks (RPL) is a standard routing framework for Internet of Things (IoT). It supports multipoint-to-point (MP-to-P), point-to-point (P-to-P) and point-to-multipoint (P-to-MP) communications. It is known that RPL’s control overhead can result in the protocol’s poor performance in P-to-P and P-to-MP communications especially in its non-storing mode of operation. Here, we present a routing protocol for the Internet of Things (RIoT) that supports MP-to-P, P-to-P and P-to-MP communications. The protocol can construct P-to-P and P-to-MP routes with relatively lower control overhead. Another salient feature of RIoT is that it supports multiple gateways in the same network with an aim to reduce memory requirement for storing a forwarding table. Furthermore, RIoT is also capable of handling mobility-based IoT use cases. To facilitate communication among nodes connected to different gateways in the same network, here we also present an inter-gateway communication mechanism. We implemented RIoT in the Contiki operating system, and it is extensively evaluated using emulation and real testbed-based experiments. We analyzed the impact of the number of gateways, radio duty cycling (RDC) and mobility on the routing protocols’ performance. Our results demonstrate that either with or without RDC RIoT demonstrates statistically significantly better packet delivery ratio, per-packet end-to-end delay and control overhead compared to the RPL-based protocol. RIoT’s multi-gateway communication architecture substantially reduces the memory requirement to store a forwarding table. Our results also demonstrate that multiple gateways in a network reduce the network partitioning problem in mobile scenarios. Hence, RIoT also demonstrates better performance in mobile scenarios compared to the RPL-based protocol.