Publications by authors named "Winchell H"

Deofix, N,N',N"-tris(dihydroxyphosphorylmethyl)-1,4,7-triazacyclononane, is a high-affinity, high-specificity chelator for first transition series cations such as iron, zinc, manganese, and copper. A 1% solution in 50% ethanol was found to be significantly better at reducing underarm malodor than a solution of 0.3% Triclosan in 50% ethanol.

View Article and Find Full Text PDF

The kinetics of N-isopropyl-p-[123I]iodoamphetamine in rat brains were determined by serial measurements of brain uptake index (BUI) after intracarotid injection; also studied were its effects on amine uptake and release in rat's brain cortical synaptosomes; and its in vivo distribution in the dog and monkey. Serial BUI correspond to a first-pass extraction efficiency of 100% and a washout half-time of approximately 318 sec. The S-(+)-isomer inhibited norepinephrine uptake in synaptosomes as strongly as D-amphetamine, but was more potent in inhibiting synaptosomal uptake of serotonin.

View Article and Find Full Text PDF

Carbon 11-labeled HCN was collected in methanol containing carrier NaCN following bombardment of 99% N2-1% H2 with 22 MeV protons. Ten new N-alkyl-p-iodobenzenesulfonamides were synthesized and labeled with 11C in radiochemical yields averaging 27% by condensation of p-iodobenzenesulfonyl chloride with the 11C-labeled aliphatic amine obtained by reduction of the intermediate 11C-labeled aliphatic nitrile prepared from Na 11CN and the corresponding alkyl bromide. They were chemically characterized and for nine of them the relationship between their molecular structure and their in vivo-distribution in rats was studied.

View Article and Find Full Text PDF

A series of aminoitriles have been synthesized and studied whose nonenzymatic dissociation with release of cyanide may be varied by modest alteration of their molecular structure from that obtained with nonenzymatic dissociation of amygdalin to that obtained from enzymatic dissociation of amygdalin by substantial quantities of beta-glucosidase. The relationship between such alterations in molecular structure and nonenzymatic dissociation is discussed. A combination of the results of these studies and studies relating molecular structure to physical localization propensity in tumors has potential in the design of chemotherapeutic agents.

View Article and Find Full Text PDF

11C-Labeled HCN was collected in water containing carrier KCN following bombardment of 99% N2-1% H2 with 22 MeV protons. 11C-Labeled mandelonitrile and p-methoxy-, p-hydroxy-, and 3,4-dihydroxymandelonitrile were synthesized from K11CN and the corresponding benzaldehyde. The initial distribution of 11C activity of these nitriles in dogs was primarily in the region of the heart, liver, and kidneys followed by rapid redistribution to the parotids and stomach with [11C]hydroxymandelonitriles.

View Article and Find Full Text PDF

There are no ideal radioactive diagnostic or therapeutic agents. There is only the best compromise at a given time between the agent's physical, chemical, and biological characteristics, its compatibility with available instrumentation needed for its use, and the ability to assure quality and availiability. This article elaborates on the parameters affecting such compromise.

View Article and Find Full Text PDF

Localization of a radiopharmaceutical agent in a "tumor" is best conceptualized in terms of the altered regional physiology attendant to the presence of the "tumor". Such localization should be expected to occur in association with other disease states characterized by similar altered regional physiology. Neoplasms, areas of inflammation, and certain phases of infarct development are characterized by increased permeability of their capillary beds to macromolecules.

View Article and Find Full Text PDF

Estimates of absorbed radiation dose and qualitative assessments of image resolution were compared for pure 131I and for 123I produced by the 122Te(d,n), 124Te(p,2n), and 127I(p,5n) 123Xe reactions. A substantial reduction in radiation dose is indicated when 123I replaces 131I, in spite of the radiocontaminants typically present 30-35 hr after the production of 123I by any of these methods. Only a marginal further reduction in radiation dose was noted with use of the most "pure" 123I as opposed to the least "pure" 123I.

View Article and Find Full Text PDF

This report evaluates the effect of prior administration of several clinically used Sn(II)-containing agents on in vivo distribution of 99mTc. Abnormal binding of 99mTc to red blood cells can occur after administration of pertechnetate to patients who have previously received tin-containing agents. Increased blood levels of tin from other causes may have similar effects.

View Article and Find Full Text PDF

The preparation and gamma-scintigraphic evaluation of the in vivo distribution patterns in dogs of a series of structurally related hydantoins labeled with the positron emitting, 20.4 min half-life radionuclide, carbon-11 are described. Carbon-11 labeled HCN was collected in water or aqueous Me2SO containing carrier KCN following cyclotron bombardment of 99% N2-1% H2 gas mixture with 22 MeV protons for 1 hr at 25-35 muA.

View Article and Find Full Text PDF

The preparation and scintigraphic evaluation of the distribution patterns in dogs of a series of structurally related aminonitriles labeled with 11C is described. Carbon-11-HCN was collected in water containing carrier NaCN following 22 MeV proton bombardment of 99% N2 and 1% H2 gas mixture for 1 hr. Ten 11C alphaN-alkylaminophenylacetonitrile hydrochlorides and 12 11C alpha-N-arylaminoarylacetonitriles were prepared from 11C-NaCN and the corresponding Schiff base, Ar-CH=N-R(Ar).

View Article and Find Full Text PDF