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Biomedical subjects

W L Anderson

Publications and source records attributed to W L Anderson.

34 records · Page 2Linked to original sources
PubMed1980

Identification of high affinity estrogen binding sites in calf uterine microsomal membranes.

Membrane-associated binding sites with high affinity and specificity for estrogens have been identified in calf uterine microsomes. The binding of 17 beta-[3H]estradiol is specific and saturable at low hormone concentration (2 nM) of high affinity (Kd = 0.5 nM) and sensitive to trypsin and other proteolytic enzymes. Binding of [3H]estradiol to membranes is inhibited by low concentrations of unlabeled 17 beta-estradiol and diethylstilbestrol (50 to 100 pM) while high concentrations of nonestrogenic steroids have little effect. The nondisplaceable binding is low and never exceeds 15% at the half-maximal point of specific binding. The maximum amount of ligand bound per mg of membrane protein is in the range of 0.4 to 1.0 pmol. Specific estradiol binding associated with microsomal fractions varies between 7 to 15% of the total binding sites. Estradiol appears not to be metabolized to any significant extent after binding to uterine membranes. Whereas the affinities of the estrogens tested are similar, the affinity of the antiestrogen, Tamoxifen, for the cytosolic receptor is at least 10 times higher than for the microsomal binding sites. In contrast to rat uterus and ovaries, the microsomal membranes from various nontarget rat tissues do not show any specific binding.

Animals↗
PubMed1980

A new lymphocyte surface protein present in normal urine. I. Isolation and physicochemical properties.

A lymphocyte surface glycoprotein designated urinary acidic antigen (UA) has been isolated from normal urine by a combination of preparative isoelectric focusing and ammonium sulfate precipitation. It has an m.w. of 14,000 to 17,500 daltons, and is approximately 60% carbohydrate and 40% amino acid in content. The protein exhibited the following physical properties: S20,omega = 1.24; v = 0.693 ml/g; E1%1 cm, 278 nm = 2.08; and pI-2.5. It appears to be unrelated to beta 2-microglobulin, protein HC, urinary proteose, microglobulin, or any previously described normal urine or human serum protein.

Amino Acids↗
PubMed1980

A new lymphocyte surface protein present in normal urine. II. Cellular distribution and biologic properties.

A protein component present in normal human urine has been found on the surface of epidermal cells and lymphocytes. This protein, called urinary acidic antigen (UA), can not be detected in concentrated fractions of normal human serum by double immunodiffusion, suggesting that it is quickly cleared from the circulation. It is readily detected, however, in sera of patients with renal failure. Although it can be eliminated from the cell surface by repeated washings with PBS, it was shown to cap with anti-UA-specific antiserum. Anti-UA suppresses PWM-induced proliferation, but not the lymphocyte response to PHA, Con A, or allogeneic cells. Thus UA appears to have a specific relationship to the pokeweed response. Whether it is a structural component of the PWM receptor is uncertain.

Animals↗
PubMed1979

Quantification of non-specific immunosuppressive factors.

A simple, reproducible and quantitative method for evaluating certain non-specific immunological inhibitors in a variety of biological fluids is described. Human lymphocytes were stimulated with PHA in the presence of colchicine. Phytohaemagglutinin stimulated a large percentage of cells and colchicine's selective blockage of mitosis limited the stimulated cells to one S phase. These conditions effectively established a maximum amount of DNA synthesis within each culture. Quantification of suppression was then achieved by measuring a decrease from this maximum. The PHA-colchicine assay was successfully used to quantify inhibition by normal plasma, normal mouse sera, mouse neonate sera, murine Ehrlich's and sarcoma I ascitic fluids and an immunoregulatory alpha-globulin peptide preparation. Because of the ability to obtain a specific inhibitory activity for the suppressive factors, this assay was particularly suited for following the isolation of inhibitors during the fractionation of suppressive substances from complex fluids.

Animals↗
PubMed1978

Quantitation of methionyl peptides in nanomole quantities by a fluorometric method.

A quantitative and highly specific method to determine low concentrations of methionyl peptides, which do not contain tryptophan or cysteine residues, has been developed. The method is based on the stoichiometry and selectivity of N-chlorosuccinimide (NCS) towards methionine and N-acetyltryptophan. N-Chlorosuccinimide reacts with N-acetyltryptophan in a 1:1 ratio to produce the N-acetyl-2-oxindolealanine--a derivative essentially devoid of fluorescence. The decrease in fluorescence intensity is approximately linear with respect to the NCS concentration. Preincubation of NCS with methionine or methionyl peptide consumes a stoichiometric amount of the reagent and the unreacted NCS is quantitated by the decrease in fluorescence intensity resulting upon incubation of the mixture with 1 eq of N-acetyltryptophan. Less than 1 nmol of methionyl peptide can be accurately quantitated by this method.

Indicators and Reagents↗
PubMed1976

The folding pathway of reduced lysozyme.

Studies on the mechanism of the glutathione regeneration (Saxena, V.P., and Wetlaufer, D.B. (1970) Biochemistry 9, 5015-5023) of hen egg lysozyme have been carried out. The first two stoichiometric disulfides in lysozyme are formed about 8 times more rapidly than the second two. Almost no enzymic activity is regained until the first two disulfides are formed, thus ruling out an all-or-none mechanism. The disulfide peptides formed early in the regeneration have been isolated and identified. The results show a limited search of folding intermediates, and outline a folding pathway. The early disulfides involve cysteinyl residues III, IV, V, and VI. At the same time cysteinyl residues I, II, VII, and VIII are still reduced, as demonstrated by their isolation as S-alkylated derivatives. At slightly later times a peptide is found which contains the (native) disulfide between cysteinyl residues II and VII. It is likely, but as yet unproven, that formation of disulfide I-VIII completes the cross-linking of lysozyme.

Amino Acids↗
PubMed1976

Spontaneously and pharmacologically provoked coronary arterial spasm in Prinzmetal variant angina.

Eleven of 21 consecutive patients with Prinzmetal angina (PMA) exhibited no significant fixed stenoses of the coronary arteries. Spontaneous coronary arterial spasm was demonstrated in 3 patients. Ergonovine maleate produced near-total occlusion of a major vessel in 3 of 4 other patients with PMA, but did not provoke spasm in 10 without PMA. The current study documents spasm as the mechanism of myocardial ischemia in some patients with normal coronary arteries and provides initial and favorable diagnostic results with provocative pharmacoangiography in this entity.

Angina Pectoris↗
PubMed1975

Automated method for determining calcium disodium edetate in iodinated contrast media parenterals.

An automated method, based on the chelating reaction of calcium disodium edetate with zirconium and the subsequent determination of excess zirconium reacted with xylenol orange, was developed. The procedure is applicable to parenterals consisting of iodinated contrast media. Familiar modules of an automated analyzer were used, but the method can be performed manually if the sample load does not warrant automation. The pH should be controlled between 0.3 and 0.5. No interferences were encountered. Twenty samples per hour can be run on prepared sample solutions. The precision of a single determination, at the 95% confidence level was plus or minus 0.008 mg/ml with a limit of detection near 0.40 mg/ml.

Autoanalysis↗
PubMed1971

Indications for coronary arteriography: risks vs. benefits.

Coronary arteriography has become a diagnostic procedure which is no longer limited to major medical centers but is being performed in many community hospitals. The procedure carries an appreciable risk, which is only justifiable by specific benefits to the patient. The benefits are related to the potential availability of newer surgical procedures of bypassing obstructive coronary arterial lesions. A specific set of criteria for the performance of coronary arteriography has been developed from a critical analysis of the ratio of risk to benefit. A survey of the risk of coronary arteriography indicates that mortality increases at least twentyfold and morbidity sixfold when this procedure is performed in laboratories with a low caseload as compared with high caseload institutions. Thus there appears to be no justification for performing coronary arteriography in the absence of proper team facilities.

Angiography↗