bluuebunny/crossref_metadata_2025 huggingface dataset:
Familiarity with Neuropsychological Assessment among Israeli Physicians
Authors: Kavé Gitit , Bloch Ayala , Maril Sari , Shabi Adi
Published: January 2020

Objective

The current study examines whether Israeli physicians are familiar with neuropsychological assessment (NPA) in general and with referral to NPA in particular.

Method

In total, 274 physicians in relevant fields participated in an online survey that targeted levels of familiarity with NPA, beliefs about assessment needs, and actual referral practices.

Results

Israeli physicians see many patients with neuropsychological difficulties, but assess fewer patients for these difficulties by themselves. Approximately 80% of participants reported that they had heard of NPA before, but only 25% knew how to refer patients to NPA. Familiarity was greater among neurologists and neurosurgeons than among family doctors.

Conclusions

Physicians had only general knowledge about NPA, with little practical understanding of how to refer patients to such a service. To increase referral rates and create consistent demand for effective neuropsychological services, neuropsychologists should engage in greater advocacy activity that will lead to clarification of referral procedures.
External Approach to Buccal Fat Excision in Facelift: Anatomy and Technique
Authors: Surek Christopher C , Kochuba Andrew L , Said Sayf Al-deen , Cho Ki-Hyun , Swanson Marco , Duraes Eliana , McBride Jennifer , Drake Richard L , Zins James E
Published: January 2020

Background

Masculinization of the face is a common finding in facelift patients. It is attributed to deflation and decent of the midface-jowls coupled with skin laxity. Fullness is evident lateral to the jowl in a small percentage due to prominent buccal fat pad (BFP).

Objectives

The authors sought to examine the anatomy of the BFP, triangulate the prominent BFP with surgical landmarks, and describe an external approach to excise the BFP during facelift surgery.

Methods

Eighteen cadaveric dissections were performed. Facelift flap was elevated and the prominent buccal extension of the BFP protruding through the superficial-musculo-aponeurotic-system was identified. Measurements were taken from the BFP to surgical landmarks: zygomatic arch, tragus, and gonial angle. The locations of the facial nerve, parotid duct, and vascular pedicle relative to the BFP were calculated.

Results

BFP was 4.1 cm inferior to the zygomatic arch, 7.5 cm anterior the tragus, and 4.5 cm medial the gonial angle. The middle facial artery supplied the BFP on the inferior-lateral quadrant in 61% and inferior-medial quadrant in 39% of specimens . In all specimens, the parotid duct traversed the BFP superiorly, and the buccal branches of the facial nerve traversed the capsule superficially.

Conclusions

The buccal extension of the BFP can pseudoherniate in the aging face. Excision may improve lower facial contour. Measurements from facial landmarks may help surgeons identify the buccal extension of the BFP intraoperatively. The surgeon must be careful of the vascular pedicle, parotid duct, and the facial nerve. The external approach safely excises buccal fat during facelift dissection while avoiding intraoral incisions and unnecessary contamination.

Level of Evidence: 4
Combined iDISCO and CUBIC tissue clearing and lightsheet microscopy for in toto analysis of the adult mouse ovary†
Authors: McKey Jennifer , Cameron Lisa A , Lewis Devon , Batchvarov Iordan S , Capel Blanche
Published: January 2020

At any given time, the ovary contains a number of follicles in distinct growth stages, each with a set of identifying characteristics. Although follicle counting and staging using histological stains on paraffin-embedded ovary sections has been the gold standard in assessing ovarian health in fertility studies, the final counts rely on extrapolation factors that diverge greatly among studies. These methods also limit our ability to investigate spatial aspects of ovary organization. Recent advances in optical tissue clearing and lightsheet microscopy have permitted comprehensive analysis of intact tissues. In this study, we set out to determine the best clearing and imaging methods to generate 3D images of the complete adult mouse ovary that could be used for accurate assessments of ovarian follicles. We found that a combination of iDISCO and CUBIC was the best method to clear the immunostained ovary. Using lightsheet microscopy, we generated 3D images of the intact ovary and performed qualitative assessments of follicles at all stages of development. This study is an important step toward developing quantitative computational models that allow rapid and accurate assessments of growing and quiescent primordial follicles, and to investigate the integrity of extrinsic ovarian components including vascular and neuronal networks.
Role of bone morphogenetic protein signaling in bovine early embryonic development and stage specific embryotropic actions of follistatin†
Authors: Rajput Sandeep K , Yang Chunyan , Ashry Mohamed , Folger Joseph K , Knott Jason G , Smith George W
Published: January 2020

Characterization of the molecular factors regulating early embryonic development and their functional mechanisms is critical for understanding the causes of early pregnancy loss in monotocous species (cattle, human). We previously characterized a stage specific functional role of follistatin, a TGF-beta superfamily binding protein, in promoting early embryonic development in cattle. The mechanism by which follistatin mediates this embryotropic effect is not precisely known as follistatin actions in cattle embryos are independent of its classically known activin inhibition activity. Apart from activin, follistatin is known to bind and modulate the activity of the bone morphogenetic proteins (BMPs), which signal through SMAD1/5 pathway and regulate several aspects of early embryogenesis in other mammalian species. Present study was designed to characterize the activity and functional requirement of BMP signaling during bovine early embryonic development and to investigate if follistatin involves BMP signaling for its stage specific embryotropic actions. Immunostaining and western blot analysis demonstrated that SMAD1/5 signaling is activated after embryonic genome activation in bovine embryos. However, days 1–3 follistatin treatment reduced the abundance of phosphorylated SMAD1/5 in cultured embryos. Inhibition of active SMAD1/5 signaling (8–16 cell to blastocyst) using pharmacological inhibitors and/or lentiviral-mediated inhibitory SMAD6 overexpression showed that SMAD1/5 signaling is required for blastocyst production, first cell lineage determination as well as mRNA and protein regulation of TE (CDX2) cell markers. SMAD1/5 signaling was also found to be essential for embryotropic actions of follistatin during days 4–7 but not days 1–3 of embryo development suggesting a role for follistatin in regulation of SMAD1/5 signaling in bovine embryos.
Compositional Flux Within the Intestinal Microbiota and Risk for Bloodstream Infection With Gram-negative Bacteria
Authors: Stoma Igor , Littmann Eric R , Peled Jonathan U , Giralt Sergio , van den Brink Marcel R M , Pamer Eric G , Taur Ying
Published: January 2020

Background

Gram-negative bloodstream infections (BSIs) represent a significant complication facing allogeneic hematopoietic cell transplant (allo-HCT) recipients, as a result of intestinal translocation during neutropenia. In this study we sought to better understand how the composition of the intestinal microbiota is connected to risk of gram-negative BSIs, expanding on our prior work in these patients.

Methods

Fecal specimens were collected from recipients of allo-HCT and analyzed using 16S ribosomal RNA gene sequencing. Samples and clinical data extending from the pretransplant conditioning period through stem cell engraftment were used in the analysis. Intestinal domination (relative abundance ≥ 30%) by gram-negative bacteria was used as predictor of gram-negative BSI using Cox proportional hazards modeling. Further analysis of microbiota composition was performed at the genus level.

Results

Seven hundred eight allo-HCT subjects were studied (7.5% developed gram-negative infection), with 4768 fecal samples for analysis. Gram-negative intestinal domination was associated with subsequent BSI, which was observed overall and individually at the genus level: Escherichia, Klebsiella, Enterobacter, Pseudomonas, and Stenotrophomonas. Fluoroquinolone prophylaxis was associated with decreased BSI and intestinal colonization by gram-negative microbes. In fluoroquinolone-prophylaxed patients, Escherichia coli was more frequently observed as breakthrough, both in terms of intestinal colonization and BSIs, compared with nonprophylaxed patients. Initial colonization by members of Ruminococcaceae and Bacteroidetes were associated with protection against gram-negative BSI.

Conclusions

Gram-negative intestinal colonization is highly predictive of BSI in the setting of allo-HCT. Fluoroquinolones appear to reduce these infections by influencing gut colonization.
Association Between the Use of Antibiotics, Antivirals, and Hospitalizations Among Patients With Laboratory-confirmed Influenza
Authors: Sutton S Scott , Magagnoli Joseph , Cummings Tammy , Hardin James
Published: January 2020

Background

Clinicians may prescribe antibiotics to influenza patients at high risk for bacterial complications. We explored the association between antibiotics, antivirals, and hospitalization among people with influenza.

Methods

A retrospective cohort study of patients with confirmed influenza with encounters during January 2011–January 2019 was conducted using data from the Veterans Affairs Informatics and Computing Infrastructure (VINCI). We compared inpatient hospitalizations (all-cause and respiratory) within 30 days of influenza diagnosis between 4 patient cohorts: (1) no treatment (n = 4228); (2) antibiotic only (n = 671); (3) antiviral only (n = 6492); and (4) antibiotic plus antiviral (n = 1415). We estimated relative risk for hospitalization using Poisson generalized linear model and robust standard errors.

Results

Among 12 806 influenza cases, most were white men (mean age, 57–60 years). Those with antivirals only, antibiotic plus antiviral, and antibiotics only all had a statistically significant lower risk of all-cause and respiratory hospitalization compared to those without treatment. Comparing the antibiotic plus antiviral cohort to those who were prescribed an antiviral alone, there was a 47% lower risk for respiratory hospitalization (relative risk, 0.53 [95% confidence interval, .31–.94]), and no other statistical differences were detected.

Conclusions

Those prescribed an antiviral, antibiotic, or both had a lower risk of hospitalization within 30 days compared to those without therapy. Furthermore, intervention with both an antibiotic and antiviral had a lower risk of respiratory hospitalization within 30 days compared to those with an antiviral alone. Importantly, the absolute magnitude of decreased risk with antibiotic plus antiviral therapy is small and must be interpreted within the context of the overall risk of antibiotic usage.
Electrophoresis and Monomolecular Layer Studies with Serum Lipoproteins
Authors: Adlersberg David , Bossak Elaine T , Sher Irving H , Sobotka Harry
Published: January 2020

The chemical analysis of the lipids in serum or plasma yields data for total lipids, phosphatides, total and esterified cholesterol, and by subtraction, for neutral fat. Zone electrophoresis, for which experimental details are given, shows the distribution of the serum lipids between α-globulin, -globulin, and a fraction which does not move in the electric field. Values are given for normal man, monkey, dog, and rabbit. Their distinctive patterns are correlated with differences in the propensity of these species to develop atherosclerosis.

Combined studies of the lipid partition and the electrophoretic profile were carried out on patients with disturbed lipid metabolism, particularly myxedema, nephrosis of various etiology, and idiopathic hyper-lipemia and hypercholesteremia. The lactescence of lipemic sera is ascribed primarily to increases of the neutral fat and corresponding increases of the electroneutral fraction of the lipoprotein electropherogram. In the Kimmeistiel-Wilson syndrome, the nephrotic syndrome in dis.betes, and in idiopathic hypercholesteremia, where the cholesterol level is increased but the neutral fat level normal, the sera usually remain clear.

In animal experiments the destruction of thyroid tissue and, in particular, the feeding of cholesterol induces hypercholesteremia and hyper-phosphatidemia in dog and rabbit. The signs of lipemia are further enhanced by the simultaneous administration of cortisone, when the total lipids in the rabbit run sometimes above 7 per cent of the serum. This experimental condition is associated with severe atherosclerotic lesions.

A model for lipoproteins is provided by the reaction between serum albumin and fatty acids, the latter in the form of monomolecular layers. The technic is described. The specificity of the ripping-off reaction and its parallelism with the dyestuff affinity of serum albumin are illustrated and discussed. The application of the reaction to the study of the "albumin defect" in infectious, rheumatic, and malignant disease is suggested.
Serum Lipoproteins
Authors: Brown Ray K , DeLalla Louis S , Kauffman Dorothy L
Published: January 2020

The larger lipoproteins of Sf greater than 10 also contain triglycerides. The action of lipases on these lipoproteins, either heparin-induced clearing factor, pancreatic lipase, or gastric lipase, yields fatty acids, glycerol, and smaller lipoproteins. Crude clearing factor attacks monoglycerides and triglycerides and is inactiveagainst several esters which plasma esterases attack. Albumin, plasma esterases, and probably other components are needed for optimal clearing factor activity. Low concentrations of diisopropyl fluorophosphate (DFP), a substance inhibiting most hydrolytic enzymes, inactivate crude clearing factor. Stoicheometric calculations made from this experiment indicate further the enzymatic nature of clearing factor. Evidence that clearing factor is different from other lipases and from esterases found in plasma is presented.

Studies with purified lipoproteins are needed to determine what alterations, if any, occur in smaller lipoproteins. The separation and purification of lipoproteins by chemical and ultracentrifugal means are described. Whole human plasma separated by Cohn's methods 6 and 9 serves as starting material for the preparation of α1 α2 β and Sf 10 and greater lipoproteins.

Studies of lipoproteins may give clues to the varied diseases associated with deranged lipid metabolism, such as xanthomatosis and atherosclerosis.
Fluorometric Determination of Urinary Metanephrine and Normetanephrine
Authors: Brunjes Shannon , Wybenga Donald , Johns Varner J
Published: January 2020

A detailed procedure for the quantitative determination of metanephrine and normetanephrine is given. Epinephrine and norepinephrine are eliminated by selective adsorption on an alumina column. Metanephrine and normetanephrine are isolated with a cation-exchange resin. Fluorescence is developed by a two-step ferricyanide oxidation at two different pH values followed by tautomerization. The concentrations of both metanephrine and normetanephrine are quantitated by differential fluorometry.
The Use of a Stabilized Partial Thromboplastin Reagent in the Partial Thromboplastin Test
Authors: Fenichel Richard L , Baker William J , Rose Lorraine
Published: January 2020

A stable sensitive partial thromboplastin reagent is prepared from an ether extract of acetone-dried bovine brain. The normal oxalated plasma partialthromboplastin time range with this reagent is 66-86 sec. Lyophilized plasmas deficient in coagulation factors give prolonged partial thromboplastin test times. Some of the properties of this reagent are discussed.
Automated Determination of Serum Alkaline Phosphatase Using a Modified Bodansky Technic
Authors: Keay H , Trew J A
Published: January 2020

An automated procedure for the measurement of alkaline phosphatase activity by a modification of the Bodansky method is described. It has been possible to adapt the Fiske-SubbaRow method for phosphate so that alkaline phosphatase is determined by a second run, immediately following the determination of inorganic phosphate.

Studies of the effect of time, pH, and concentration of barbital on the enzyme activity are discussed, and the advantages of the method are listed.
The Estimation of Galactose in Plasma Using Galactose Oxidase
Authors: Ford J D , Haworth J C
Published: January 2020

The estimation of galactose in plasma by the enzyme system galactose oxidase-peroxidase was investigated. The method was found to be relatively specific for galactose although xylose and ascorbic acid reacted to a slight degree with the enzyme; lactose also reacted with the enzyme, probably because partial hydrolysis of the disaccharide released galactose. The relationship between absorbance and concentration of galactose greater than 20 mg./100 ml. was linear. Below this value the line curved toward the origin, making accuracy uncertain unless a number of aqueous standards can be run with each batch of estimations.
Sialic Acid (N-Acetylneuraminic Acid) in Human Serum
Authors: Cabezas J A , Porto J Vazquez
Published: January 2020

A simple spectrophotometric method is described for the sialic acids which utilizes the reaction with resorcinol and extraction with butyl acetate-n-butanol as a solvent. Normal values for adults, utilizing N-acetylneuraminic acid as a standard, were found to be 60 ± 10.4 mg./100 ml. Values for newborn babies averaged 40.4 ± 5.7. Similar values were found for specimens from 2-month-old infants to 27-year-old adults. Higher values were noted in the case of rickets, severe burns, rheumatic disease, and tuberculosis.
Effects of Age and Sex on the Electrophoretic Fractions of the Serum Glycoprotein
Authors: Pearce R H , Watson E M , Stodolski R , Mathieson J M , Theoret J J
Published: January 2020

Specimens of serum were collected from 198 clinically healthy persons, chosen to provide approximately 10 males and 10 females in each decade up to the tenth. After electrophoretic separation using the Spinco method B, the strips were stained by the periodic acid-Schiff reaction according to Köiw and Grönwall (Scand. J. Clin. Lab. Invest. 4, 244, 1952) and scanned on the Analytrol integrating densitometer at 550 mµ. Total glycoprotein was estimated on an ethanol precipitate by the tryptophan-borosulfuric acid reaction (Badin, Jackson, and Schubert, Proc. Soc. Exptl. Biol. Med. 84, 288, 1953).

The analytical error and normal values for the method were estimated; those for males did not differ from those for females. The means and standard deviations for groups showing statistically significant differences (P <0.05) were, in mg./100 ml. of serum: total, under 70 years, 148 ± 19; total, over 70 years, 164 ± 20; albumin, 23.1 ± 6.6; alpha1, 12.5 ± 4.3; alpha2, under 60 years, 47.4 ± 12.1; alpha2, over 60 years,59.1 ± 16.0; beta, under 10 years, 27.2 ± 6.6; beta, 10 to 90 years, 38.4 ± 8.2; beta, over90 years,54.0 ± 17.7; gamma,26.4 ± 7.1. The results were compared with those obtained by other published procedures.
Micromethods for Measuring Phenylalanine and Tyrosine in Serum
Authors: Wong Paul WK , O'Flynn Margaret E , Inouye Tohru
Published: January 2020

Spectrophotofluorometric micromethods for the determination of phenylalanine and tyrosine on 25 µl of serum are described. These methods were applied to detect phenylketonuria among homozygotes and heterozygotes and in the newborn population. The data presented agree with those previously reported. (1) Phenylketonurics have markedly elevated serum phenylalanine and lower serum tyrosine than the controls. (2) The heterozygotes have a higher fasting serum phenylalanine and, after a standard oral phenylalanine test, show a higher and more prolonged rise of serum phenylalanine than the controls. There was a lesser increase of serum tyrosine after phenylalanine loading in the heterozygotes than the controls. (3) Premature infants of low birth weight have higher serum phenylalanine and tyrosine levels than normal birth weight infants, presumably due to enzyme immaturity. Simultaneous determinations of serum phenylalanine and tyrosine will differentiate newborn infants who are suspected to be phenylketonurics from the homozygotes (phenylketonurics).
An Automated Determination of Alkaline Phosphatase Utilizing p-Nitrophenol Phosphate
Authors: Sterling Rex E , Wilcox Alan A , Ware Arnold G , Umehara Mary K
Published: January 2020

A technic is described for the automated determination of serum alkaline phosphatase. This method permits a production rate of 60 determinations per hour on 0.2 ml. of serum per determination. Calculations are simplified since no serum blank is required.
A Modified Procedure for the Estimation of Total 17-Hydroxycorticosteroids (Porter-Silber Chromogens) in Urine
Authors: Liu John HC
Published: January 2020

A modified procedure for the determination of urinary 17-hydroxycorticosteroids (di-hydroxy-acetonyl-corticoids) is described. The use of ethyl ether in a single extraction step and the stabilization of the phenylhydrazine-sulfuric acid reagent with sodium chloride are the unique features of the method. Studies of chromogenicities of steroids, recovery, pH effect on extraction, and salt effect on the stability of Porter-Silber reagent in the presence and absence of light during storage are reported; chemical aspects of chromogenic development of various steroids are discussed, clinical ranges compared, and interpretations evaluated.
Urinary Pregnanediol and Pregnanetriol: Spectrophotometric Determination Following Aluminum Oxide Column Chromatography
Authors: Klein Daniel , Chernaik Joseph M
Published: January 2020

A modification of the procedure for urinary pregnanediol and pregnanetriol is described employing enzymatic hydrolysis, solvent extraction, separation on aluminum oxide by partition gradient elution, and determination by use of the sulfuric acid color reaction. A procedure has been devised for overcoming chromogenic interference by impurities, especially with the pregnanediol determination, based on utilization of the absorption curve characteristics of these two steroidal chromogens in H2S04. One essential step is the incorporation of the standards into one of a pair of urine extracts; a second is the collection of a small number of eluates for both the pregnanediol and pregnanetriol fractions. By the wavelength of peak absorption obtained in H2S04 for each eluate residue, the proper eluates are then selected for the determination of each of the two steroids. The method requires simple equipment readily available in clinical chemistry laboratories, and gives results that compare very favorably with those obtained with other procedures.
The Precision, Accuracy, and Inherent Errors of Automatic Continuous Flow Methods
Authors: Thiers R E , Oglesby K M
Published: January 2020

An automatic continuous-flow system was evaluated under routine daily use for six constituents, sodium, potassium, chloride, carbon dioxide, urea, and glucose. Two parameters have been quantified, interaction between samples and instrumental drift. Results also were influenced by the available amount of sample. Application of correction technics is shown to improve the accuracy of the automatic-analysis system.
Analyses on Heat-coagulated Blood and Serum
Authors: London Morris , Marymont Jesse H
Published: January 2020

A method for the quantitative separation of serum urate from the proteins present, that does not employ chemical precipitation, is presented. The separation is accomplished by heat coagulation of serum and the subsequent aqueous extraction of the purine from the intact coagulum. Serum is placed at the bottom of a container of sufficient size to permit the formation of a thin layer and then coagulated in a boiling-water bath. The resultant coagulum is firm, adherent to the container, and not easily disrupted. Water is then added to cover the coagulum and the urate extracted. The urate present in the extract is determined using a phosphotungstate reduction method.
Enzyme Activities of Human Inferior Vena Cava
Authors: Kirk John Esben
Published: January 2020

A comparison was made of activities of 15 different enzymes in normal tissue samples of the inferior vena cava and aorta derived from the same subjects. Statistically significant differences between venous and arterial specimens were observed for 10 of these enzymes. Comparative studies on the intermediary metabolism of the vascular walls may disclose some of the factors responsible for the low susceptibility of human veins and the high susceptibility of human arteries to sclerotic changes.
An Automated Method for the Determination of Serum Bilirubin
Authors: Golub Murray
Published: January 2020

The bilirubin method of Rand and DiPasqua (3), which utilizes a stabilized diazonium salt solution of 2,4 dichloraniline, has been adapted to automatic chemical analysis. Both total bilirubin and "1-min. reacting" bilirubin can be assayed with good accuracy and precision. Data are presented to show excellent agreement with the manually performed procedure and the procedure of Malloy and Evelyn (1), which was used as the reference method.
Modern Methods for Determining Cerebrospinal Fluid Protein
Authors: Watson Derek
Published: January 2020

A simple and rapid micro method for the determination of albumin and total protein in cerebrospinal and other body fluids is presented. It is based on the UV spectrophotometric measurements of neutral and acid-alcohol-treated spinal fluid and is shown to be accurate and reproducible. Using spectrophotometry at 220 mµ and two other recently improved technics, 84 specimens of spinal fluid from infants were analyzed for total protein. The results obtained showed good agreement over the range 30-200 mg./100 ml.
A Rapid Method for Cholesterol Determination with a Single Reagent
Authors: Zurkowski P
Published: January 2020

A method for the determination of serum cholesterol, using a single reagent, is described. This method is simple, rapid, and economical, and prevents some of the errors inherent in the manipulative process of earlier procedures.
Seroflocculating Steroids
Authors: Chang Frederic C
Published: January 2020

The basis and plan of research on a group of steroids having seroflocculating activity, with the aim of developing a test for use in diagnosis of cancer,† are reviewed. Compounds classified into activity groups in earlier reports have been summarized, tentative activity-structure relationships are indicated, and a relative group-activity series has been derived from the screening. A discussion of the research is given.
Automated Determination of Serum Glutamic Oxalacetic and Glutamic Pyruvic Transaminase
Authors: Schaffert Roscoe R , Kingsley George R , Getchell Gloria
Published: January 2020

The determination of serum glutamic oxalacetic and glutamic pyruvic transaminase has been simplified by the use of automated analysis. The flow diagrams, concentration of reagents, and calculation of the color unit in terms of the Karmen unit are shown for 2,4-dinitrophenylhydrazine and 6-benzamido-4-methoxy-m-toluidine diazonium chloride as the reacting dyes. Advantages of both methods are compared and discussed.
A New Method for the Determination of Ascorbic Acid in Urine
Authors: Kum-Tatt Lee , Leong P C
Published: January 2020

A simple method for the determination of ascorbic acid in urine was developed. The method is based on the quantitative reduction of mercuric chloride to mercurous chloride at pH 3.5-5.0. The insoluble mercurous chloride was separated by centrifugation, dissolved in excess standard iodine-potassium iodide solution and back-titrated with standard sodium thiosulphate. The method has precision, and as little as 1.0 mg. of ascorbic acid per 100 ml. of urine can be determined with an accuracy of ± 3%. Common substances found in urine do not interfere.
Screening Test for Fast Isoniazid Inactivators
Authors: Eidus L , Hamilton E J
Published: January 2020

A screening test is described for assaying fast inactivators of isoniazid (INH) in serum. Trichloracetic acid filtrates are reacted with a trans-cinnamaldehyde reagent to form a colored hydrazone derivative of INH. The metabolic degradation of the drug is discussed as well as interferences. The color is read at 352-354 mµ.
Coproporphyrin Analyses on Random Urine Samples
Authors: Rogers Charles J
Published: January 2020

The fluorometric procedure of determining coproporphyrin has been adapted to determine coproporphyrin on random urine specimens. This adaptation depends on determining both coproporphyrin and creatinine. A mathematical relationship is established for the amount of coproporphyrin excreted when 1200 mg. of creatinine is excreted.

An important advantage of the random procedure is the elimination of the waiting period of 24 hr. for the urine collection. This is particularly important in porphyric urines since much of the porphyrin is reduced to forms that are sensitive to light, with the result that pathologic levels of coproporphyrin may thus be overlooked.
Differential Spectrophotometric Determination of Calcium
Authors: Radin Nathan , Gramza Adalbert L
Published: January 2020

The appearance of kits for the determination of micro amounts of calcium stimulated our interest in the use of Eriochrome Blue SE for this analysis. A study of spectrophotometric curves indicates that, at pH values above 13.7, calcium will complex and cause a change of dye absorbance while magnesium does not complex with the dye. A differential spectrophotometric technic is described in this paper in which the spectrophotometer is set at zero absorbance with a dye-calcium standard solution or a dye-calcium sample solution as reference and the absorbance of the dye solution then measured. For a set of standards the absorbance-calcium relationship is linear. With the Beckman spectrophotometer, Model DU, it has been found that 1 part of serum to 100 parts of alkaline dye solution (100 λ of serum to 10 ml. alkaline dye solution) can be used. The technic shows greater sensitivity and accuracy than do previous methods using Eriochrome Blue SE.
Lactic Dehydrogenase
Authors: Weinberg Myron S , Adler Daniel H
Published: January 2020

Determination of lactic dehydrogenase (LDH) activity has been shown to have diagnostic value in pathologic states involving tissue necrosis and neoplasia. Necrotizing tissues release this enzyme, which catalyzes the reduction of pyruvate to lactate or the reverse, in an active state. As a result of this release, the enzyme appears in body fluids, notably the blood. Increase of this activity over normal indicates necrosis.

The present paper compares the results of the Wroblewski and LaDue and the Wacker et al., methods for measuring LDH activity.

Results of the two methods were found to be not comparable. No calculation can be found to relate the results of the two analytical methods. Only 18 of 30 samples gave abnormally high results by both methods. Changes between serial samples drawn on the same patient are not always in the same direction when measured by both methods. Lack of mathematical correlation between the kinetics of the pyruvate-to-lactate reaction and the lactate-to-pyruvate reaction is assumed to explain this.
Determination of Uric Acid
Authors: Crowley Leonard V
Published: January 2020

An automated method is described for the determination of uric acid by a carbonate method. Since uric acid is separated from proteins by dialysis, the loss of uric acid due to protein precipitation in manual methods is avoided. There is no appreciable interference from salicylates, high levels of blood sugar, or ascorbic acid. The method shows an acceptable correlation with the uricase method.
Determination of the Iron-binding Capacity of Blood Serum
Authors: Nadeau Guy , Fortin Benoit
Published: January 2020

A simple experiment was performed to ascertain whether procedures for estimating the iron-binding capacity (IBC) of blood serum are quantitative. This was accomplished by adding β-globulin (obtained by fractionation of human plasma) to various serum specimens. The β-globulin solutions were first assayed for their IBC. Their addition to serum in these recovery experiments provided data for evaluation of methodology.
Semimicro Flame Photometry of Serum Sodium and Potassium
Authors: Dryer R L
Published: January 2020

A method for the determination of serum sodium and potassium involving only a single serum dilution is described.

Samples of 0.1 ml. of serum suffice for both determinations, but larger samples may also be used.

By careful control of the lithium concentration and the dilution factor the mean relative photometric error may be held to no more than 1 per cent under normal circumstances of operation.
Blood pH Measurement with the Glass Electrode
Authors: Natelson Samuel , Tietz Norbert
Published: January 2020

A study has been described to explain the tendency of fingertip blood from normal individuals to drift to alkaline pH more rapidly than the blood of venous serum at 37°. This occurs even under oil and without loss of CO2. Evidence is offered to indicate that this phenomenon is due to the release of carbonic anhydrase in greater concentrations into the serum when the finger is punctured than when venipuncture is performed. An explanation is offered for the fact that serum from patients in acidemia with low CO2. content will not drift at 37°.

It is suggested that blood pH determinations be made by collecting the specimen under oil, cooling rapidly to room temperature, and performing the determination under oil on the separated serum.
Serum Protein Analysis by Electrophoresis and by the Wolfson-Cohn Chemical Method
Authors: Eriksen Nils , Ellerbrook Lester D , Lippincott Stuart W
Published: January 2020

One hundred serum specimens from healthy and diseased adults were analyzed for the major protein constituents by free electrophoresis and by the Wolfson-Cohn chemical method. Albumin values obtained by the two methods were well correlated and were also in good average numerical agreement. The γ-globulin values were well correlated, but were not in quite such good numerical agreement, on a percentage basis, as were the albumin values. The α-globulin values were poorly correlated, as were also the β-globulin values.

Electrophoretic examination of some of the chemical fractions indicated that part of the discrepancy between the two methods was caused by faulty chemical fractionation, particularly with respect to the globulin fractions.

Determination of total solids retained by a dialysis membrane (TS) in 22 serum specimens confirmed the proportionality between TS and the electrophoretic-pattern area, and emphasized a source of error of undetermined magnitude in the calculation of electrophoretic results from simple protein totals.
Semimicro Method for the Determination of Salicylate Levels in Blood
Authors: Routh J I , Paul W D , Arredondo Emilio , Dryer R L
Published: January 2020

A micro method for salicylates capable of determining levels of 0 to 50 µg./ml. on fingertip blood specimens has been developed. The method is characterized by low plasma or whole blood blanks, the ability to measure very low salicylate levels, and sufficient range to compare favorably with the macro method of Brodie et at. at higher levels.
Determination of Glucose with a Research Model Aminco "Rotochem" by the Hexokinase Reaction
Authors: Hasson William , Penton James R , Widdowson Graham M
Published: January 2020

A method involving the hexokinase reaction is described for determining glucose in serum with a Research Model Aminco "Rotochem." The need to measure a separate sample blank is eliminated by using the computational capabilities of a small computer interfaced with the Rotochem. In this modification of the method of Tiffany et al., a cubic curve is fitted to the initial portion of the reaction path. Sample blanks are calculated by extrapolation back to zero time. The procedure is precise and results correlate well with those for an accepted automated procedure in which the same reaction is used.
Separation of Tissue and Serum Creatine Kinase Isoenzymes by Ion-Exchange Column Chromatography
Authors: Mercer Donald W
Published: January 2020

I describe a simple, rapid anion-exchange column chromatographic technique for separating the creatine kinase (CK) isoenzymes in human serum and tissue. Extracts of CK-rich tissues (skeletal muscle, cardiac muscle, and brain) were used to determine optimum conditions for separating CK isoenzymes MM, MB, and BB. Samples, layered on mini-columns (0.5 x 6.0 cm) of DEAE-Sephadex A-50, were eluted stepwise with Tris-buffered sodium chloride (100, 200, and 300 mmol/Iiter). Column effluents were assayed by the Rosalki CK method. Distribution of total activity among the eluted fractions was tissue-specific and reproducible. Evaluation of sera from 71 patients with myocardial infarction and other diseases associated with elevated CK activity revealed isoenzyme patterns that resembled those of either cardiac muscle or skeletal muscle. Cardiac pattern (presence of MB isoenzyme) and clinical documentation of myocardial infarction were 100% correlated in the 35 patients so studied.
CEA-Like Material in Fluid from Benign Cysts of the Breast
Authors: Fleisher Martin , Oettgen Herbert F , Breed Charles N , Robbins Guy F , Pinsky Carl M , Schwartz Morton K
Published: January 2020

A preliminary survey of carcinoembryonic antigen (CEA) concentrations in 23 breast-cyst fluids (BCF) and blood plasma has revealed markedly increased concentrations of CEA-like material in BCF as compared to its concentrations in plasma. Chromatography on Sephadex G-200 indicated the immunoreactive CEA component extracted from BCF corresponds to a glycoprotein with a molecular weight of at least 200 000.
Principles of Competitive Binding Assays (Saturation Analyses). II. Sequential Saturation
Authors: Zettner Alfred , Duly Peggy E
Published: January 2020

The principles of sequential saturation as a form of competitive binding assays are discussed in detail and differentiated from those of equilibrium techniques. The rationale of its applicability in practice and its potential to increase sensitivity under certain assay conditions are demonstrated with three binding systems involving digoxin, insulin, and folates. The advantages and disadvantages of the sequential saturation technique are outlined.
Evaluation of an Improved Pneumatic-Tube System Suitable for Transportation of Blood Specimens
Authors: Pragay D A , Edwards L , Toppin M , Palmer R R , Chilcote M E
Published: January 2020

An improved version of a pneumatic-tube system built by Amsco, Inc. (Erie, Pa.) and its subsidiary ATC (San Rafael, Calif.) for blood-sample transportation incorporated two innovations: The sample carrier travels at a lower speed than in the previous conventional systems, and it is decelerated gradually on arrival. This tube system was pilot tested for efficiency by running blood-filled Vacutainer tubes through the 63.6-rn (210-feet) tube 10 times, a total running distance of 636 m. Serum lactate dehydrogenase and acid phosphatase activities, and potassium, all sensitive chemical indicators of erythrocyte membrane damage, were measured in blood specimens in partially or totally filled Vacutainer tubes and the results compared with those obtained from controls. No alterations were found in serum test results after 10 or 20 repetitive cycles in the totally filled tubes, but significant changes did occur in partially filled tubes after 20 cycles. If the limitations are observed, this system appears to be suitable for blood-specimen transportation.
Identification of Hemoglobins and Hemoglobinopathies by Electrophoresis on Cellulose Acetate Plates Impregnated with Citrate Agar
Authors: Schneider Rose G , Hosty Thomas S , Tomlin Gary , Atkins Ruby
Published: January 2020

We describe a method of electrophoresis of hemoglobin on cellulose acetate plates impregnated with citrate agar, which remain stable for many months and are used to confirm rapidly the presence of hemoglobins S and C and the hemoglobinopathies associated with them. The method also provides excellent separations of hemoglobins F and A and reliable identification of genetically determined hemoglobin abnormalities in the newborn.
Measurement of Antibodies to Insulin in Serum
Authors: Dixon K
Published: January 2020

I describe a method for measuring insulin antibodies in insulin-treated subjects. The antibodies are characterized by maximum binding capacity and affinity constant. Endogenous and therapeutic insulin interferes in insulin antibody assay, and it is removed by dextran—charcoal treatment at pH 3.5. Endogenous total and free insulin may be measured by a simple extension of the method.
Assessment of the Reference Method for Determination of Total Calcium in Serum
Authors: Pickup John F , Jackson Malcolm J , Price E Margaret , Brown Stanley S
Published: January 2020

The Reference Method [Clin. Chem. 19, 1208 (1973)] for determination of calcium in serum has been critically assessed, both to evaluate its performance in one laboratory and to identify ambiguities and errors in the published texts. Within-run and between-run precision and bias have been estimated, and a revised protocol is presented.
Use of Tris Buffers for Quality Control of Blood pH
Authors: Ladenson Jack H , Smith Carl H , Dietzler David N , Davis J E
Published: January 2020

Tris(hydroxymethyl)aminomethane buffers have been established as sensitive and convenient indicators of the reliability of blood pH analysis. These buffers were compatible for routine use with blood-pH equipment from major manufacturers, except for two instruments. A seven-month study demonstrated the necessity of a routine quality-control program, as well as the need for systematic cleaning and maintenance of pH equipment. Tris(hydroxymethyl)aminomethane buffers were found not to be suitable as primary standards because we could not obtain the stated values with commercial pH equipment that had been standardized with phosphate buffers from the National Bureau of Standards. The relative standard deviation for measurement of hydrogen ion activity, 4.1% , indicates a need for improvement in the design and operation of equipment for the measurement of blood pH.
The Hoesch Test: Bedside Screening for Urinary Porphobilinogen in Patients with Suspected Porphyria
Authors: Lamon Joel , With Torben K , Redeker Allan G
Published: January 2020

A little-known procedure for porphobilinogen screening, the Hoesch test, was examined for sensitivity, specificity, and utility as compared to the Watson-Schwartz test. The data demonstrate that its sensitivity is similar to that of the Watson-Schwartz test. The Hoesch test, however, is without false-positive reactions secondary to urobilinogen, and its simplicity makes it easier to use and more easily interpretable. We conclude that the Hoesch test should replace the Watson-Schwartz test for urine porphobilinogen screening in suspected cases of acute intermittent and variegate porphyria.
2-Amino-2-methyl-1-propanol as the Alkalizing Agent in an Improved Continuous-Flow Cresolphthalein Complexone Procedure for Calcium in Serum
Authors: Moorehead Wells R , Biggs Homer G
Published: January 2020

We describe an improved cresolphthalein complexone procedure for calcium in which diethylamine is replaced by a nontoxic amino alcohol. Advantages of the procedure are increased sensitivity, excellent baseline stability, a more optimum reaction environment (pH 10.0) that eliminates blanking problems, and freedom from interference by magnesium. Values obtained by this method are not significantly different (P < 0.05) from those obtained by atomic absorption spectrophotometry.
Rapid Gas-Chromatographic Determination of Amphetamine and Methamphetamine in Urine
Authors: Jain Naresh C , Sneath Thomas C , Budd Robert D
Published: January 2020

A simple, rapid procedure is described for measuring amphetamine and methamphetamine in urine by gas chromatography, with use of a flame ionization detector. This method is sensitive to subtherapeutic concentrations (0.1 µg/ml or less), and is especially useful in clinical situations where an accurate and quantitative result is needed in less than 30 min. With the method, amphetamine and methamphetamine can be determined as the free bases on a 10% Apiezon L-10% KOH column and as their trifluoroacetamide derivatives on a 3% OV-17 column. This dual analysis eliminates false positives and any interfering substances that may be present in the urine, and is thus a specific method for the two drugs.
Creepage of Estrogens vs. Loss by Sorption on Glassware
Authors: Kushinsky Stanley , Anderson Marilyn
Published: January 2020

Creepage and decomposition by atmospheric pollutants account for many if not all of the losses that have been attributed previously by others to sorption on glassware. Significant creepage occurs only in uncovered (or incompletely closed) vessels, in the presence of salts and in the absence of proteins (such as gelatin). More creepage occurs in vessels that have been freshly cleaned by treatment with heat, cleaning solution, or organic solvents, when the volume of solution is relatively small compared with the capacity of the vessel and at higher dilutions. In addition, the rate of creepage of intact estrogens is greater than that of the decomposition products. We have found no evidence for sorption of estrogens onto glass from buffered aqueous solutions or decomposition in tightly closed containers in the absence of proteins. Under the conditions we used for silanization, creepage was reduced drastically but not eliminated totally.
Transport of Beta-Carotene in Serum of Individuals with Carotenemia
Authors: Mathews-Roth Micheline M , Gulbrandsen Christian L
Published: January 2020

We studied distribution of carotene in the various serum lipid fractions of carotenemic and noncarotenemic individuals. We found that the amount of carotene in each lipoprotein fraction is increased in the serum from carotenemic individuals, but that the relative increase is significant only in the low-density lipoprotein and high-density lipoprotein fractions. There was no significant difference between the cholesterol concentrations of each fraction of the carotenemic individuals' and noncarotenemic individuals' sera, indicating that serum betalipoprotein is not increased in carotenemia.
Alcohol, Traffic, and Chemical Testing in the United States: A Résumé and Some Remaining Problems
Authors: Mason M F , Dubowski K M
Published: January 2020

We give a résumé of "chemical testing" for alcohol in the United States in connection with traffic-law enforcement. Recent procedural and instrumental developments are briefly reviewed. Various factors involved in discrepancies between the results of analyses of near-simultaneous venous blood and breath specimens from the same subject are examined. Because the causes of these discrepancies cannot adequately be controlled in law-enforcement practice, we suggest that calculation of a blood-alcohol concentration based on the result of a breath analysis be abandoned. We recommend that when breath analysis is performed for law-enforcement purposes, the interpretation of the result should be statutorily based on the amount of alcohol found per unit volume of alveolar ("deep-lung") air. Serum or plasma of capillary blood is recommended as the sample when blood is to be analyzed.