The authors studied the biodisposition and hepatobiliary transport of two potential magnetic resonance imaging contrast agents, the iron (III) chelates of N,N'-bis(2-hydroxybenzyl)ethylene-diamine-N,N'-diacetic acid (HBED) and diastereomeric N,N'-ethylenebis(2-hydroxyphenylglycine) (EHPG). Fecal and urinary excretion (mean +/- standard deviation), respectively, of FE-59 over 7 days in rats given tracer doses of the contrast agents were 67% +/- 2% and 22% +/- 1% for Fe-59-HBED and 22% +/- 2% and 26% +/- 5% for Fe-59-EHPG. In bile duct-cannulated rats given 0.05-mmol/kg doses labeled with Fe-59, 52% +/- 8% of Fe-59 from Fe-59-HBED but only 17% +/- 3% of that from Fe-59-EHPG was excreted into the bile within 90 minutes. Bromosulfophthalein, but not taurocholate or oxyphenonium, was shown to compete with both agents for hepatobiliary transport. Enterohepatic recirculation of both agents was less than 1%.

Animals↗

PubMedDate not supplied

Dynamic properties of blood flow and leukocyte mobilization in infected flaps.

Two aspects of the inflammatory response to infection--blood flow alteration and leukocyte mobilization--are investigated in the canine model. The elevation of paired musculocutaneous (MC) and random pattern (RP) flaps allowed comparison of healing flaps with significant differences in blood flow (lower in random pattern flaps) and resistance to infection (greater in musculocutaneous flaps). Blood flow changes as determined by radioactive xenon washout were compared in normal skin and distal flap skin both after elevation and following bacterial inoculation. Simultaneous use of In-111 labeled leukocytes allowed determination of leukocyte mobilization and subsequent localization in response to flap infection. Blood flow significantly improved in the musculocutaneous flap in response to infection. Although total leukocyte mobilization in the random pattern flap was greater, the leukocytes in the musculocutaneous flap were localized around the site of bacterial inoculation within the dermis. Differences in the dynamic blood flow and leukocyte mobilization may, in part, explain the greater reliability of musculocutaneous flaps when transposed in the presence of infection.

Abdominal Muscles↗

PubMedDate not supplied

Magnetic resonance imaging of splenic iron overload.

The value of magnetic resonance (MR) imaging in assessing iron overload in the spleen was retrospectively investigated in 40 consecutive patients. MR appearance, measure of signal intensity and T1- and T2-relaxation times were correlated with the histologically determined level of iron in the spleen in each patient. Histologic examination revealed no iron overload in 19 patients, mild iron overload in seven, moderate iron overload in six, and severe iron overload in eight. All 19 patients with no splenic iron overload and 11 of the other 21 patients with splenic iron overload were correctly identified by MR imaging (sensitivity 52%, specificity 100%, accuracy 75%). Splenic iron overload was diagnosed when a decrease of signal intensity of the spleen compared with those of adipose tissue and renal cortex was demonstrated. MR images demonstrated all eight cases of severe, three of the six cases of moderate, and none of the seven cases of mild iron overload. Only spleens with severe iron overload had a significant mean decrease in signal intensity and T1- and T2-relaxation times. Although specific, MR imaging is poorly sensitive to splenic iron overload.

Adolescent↗

PubMedDate not supplied

Chemiluminescent substrates for detection of restriction fragment length polymorphism.

Five new enzyme-triggered dioxetane substrates were evaluated for restriction fragment length polymorphism (RFLP) analysis of HaeIII- restricted DNA. Of these, one substrate designated CDP-Star provided unsurpassed sensitivity within one working day without the presence of an enhancer. Far greater sensitivity was obtained from chemiluminescent detection of DNA on MSI neutral membranes than the sensitivity obtained from six day film exposures of 32P labelled insert probes on PALL B membranes, including the detection of most low molecular weight alleles. For nylon membranes better suited for alkaline phosphatase-triggered chemiluminescent detection of DNA, high salt/neutral pH southern transfer conditions were better than alkaline southern transfer conditions.

DNA↗

PubMedDate not supplied

Opacification of falx and tentorium during cerebral angiography: preliminary report.

Explore the source record for details and available documents.

Adult↗

PubMedDate not supplied

An automated fluorescent excitation analysis system for medical applications.

The use of stable tracers assayed by x-ray fluorescent excitation analysis has proven advantageous over other stable or radioisotopic techniques in a number of clinical and investigative situations. An automated fluorescent excitation analysis system for medical application has developed. Its design parameters and performance are described.

Blood Volume Determination↗

PubMedDate not supplied

Imaging characteristics of a small germanium camera.

A high purity germanium gamma-camera has been developed and is currently being evaluated. This camera incorporates unique performance parameters such as a 2 mm full-width spatial response function with rejection of multiple-scatter in the detector, a 2.2% FWHM energy resolution for 99 mTc, a 180 nsec paralyzable dead-time, and a 2 mu sec non-paralyzable dead-time. Imaging studies demonstrate the superior capabilities of this instrument.

Animals↗