Hepatic hemangiomas: evaluation by magnetic resonance imaging and technetium-99m red blood cell scintigraphy

A study was performed to evaluate and compare the sensitivity of magnetic resonance imaging (MRI) and radionuclide blood-pool scanning in the detection of hepatic hemangiomas. All patients had known hemangiomas which were first detected on either ultrasound or computed tomography. Sixteen patients with a total of 23 lesions were investigated. Eleven patients had both MRI and blood-pool scans performed. In the group studied by both modalities, 18 lesions were detected ranging in size from 1 to 11 cm. All lesions were detected by both techniques. However, two of the 18 lesions had an atypical appearance on MRI. Our experience to date indicates that the anatomic location and specific diagnosis of hemangiomas can be made with a high degree of certainty when both MRI and blood-pool scanning techniques are utilized.

Computerized chest tomography in asbestos workers suspected of having pleural disease

Forty-five computerized tomographic (CT) chest studies were performed on workers suspected of having pleural disease after being exposed to asbestos material. Ten of the 45 reviewed were court cases, and 32 workers acutely exposed at University of California-Los Angeles (UCLA) were studied with routine four views of the chest. CT confirmed the initial interpretation of chest films obtained at UCLA.

Magnetic resonance imaging artifacts: mechanism and clinical significance

Many types of artifacts may occur in magnetic resonance imaging. These artifacts may be related to extrinsic factors such as patient motion or metallic artifacts; they may be due specifically to the MR system such as power gradient drop off and chemical shift artifacts; they may occur as a consequence of general image processing techniques, as in the case of truncation artifacts and aliasing. Change in patient position, pulse sequence, or other imaging variables may improve some artifacts. Although reduction of some artifacts may require a service engineer, the radiologist has the responsibility to recognize MR imaging problems. The radiologist's knowledge of MR imaging artifacts is important to the continued maintenance of high image quality and is essential if one is to avoid confusing artifactual appearances with pathology.

Accurate demonstration of hepatic infarction in liver transplant recipients

Serial HIDA scanning has proven to be a valuable tool in the postoperative management of liver transplant patients. Previous reports have documented its efficacy in detecting biliary leakage, abscess, and rejection. We have also found HIDA scanning to be a sensitive method for detecting early hepatic infarction before ultrasonographic changes occur. Two cases are presented to demonstrate the characteristic findings seen with hepatic infarctions.

Hepatic abscess in liver transplantation. Accurate diagnosis and treatment

Serial HIDA scanning was performed on a patient following liver transplantation. During the patient's course he developed biliary obstruction that manifested as a photopenic region in the liver, on the HIDA scan which filled in on the delayed views. The patient subsequently developed a region in the superior portion of the right lobe of the liver that did not fill in with activity on delayed views. The patient was experiencing low-grade fevers and was clinically believed to have either an abscess or an episode of rejection. A gallium scan was performed revealing a photopenic defect in the same region as the HIDA. Because of the clinical suspicion of abscess, a percutaneous transhepatic drainage study was performed, revealing a large abscess cavity in the suspect area within the liver. Following the drainage the patient did well. This case illustrates the usefulness of serial HIDA scanning in patients who have received liver transplants. It also is important to note that the gallium scan was negative in this hepatic abscess. In the authors' opinions, the finding of an intrahepatic fluid collection in a septic patient that does not fill with activity on the HIDA study, should be considered the source of the infection, until proven otherwise, and should be drained regardless of the findings of other studies.

The interaction of platelet proteins with three fibroblast-derived collagenases

Three collagenases were purified from the culture medium of human skin fibroblasts using ammonium sulfate fractionation, ion-exchange chromatography and gel filtration. The cationic collagenase had a molecular weight of 42,000; two anionic collagenases had molecular weights of 63,000 and 115,000. Preincubation of the individual collagenases with purified human and bovine platelet heparin binding proteins resulted in the inhibition of the two anionic activities, but only by bovine low heparin affinity platelet protein (beta-TG). Such inhibition was dose-dependent at the microgram level, was not antagonized by heparin, and persisted even when the collagenases had been transformed into their 53,000 and 105,000 forms through treatment with p-aminophenylmercuric acetate. Neither human nor bovine high heparin affinity platelet factors (PF-4) nor human low heparin affinity platelet protein (beta-TG) were inhibitory to any of the three collagenases studied. This suggests that the ability of platelet proteins to inhibit collagenase is specifically influenced by the ionic nature of the enzyme and this inhibition is specifically dependent upon the species and type of platelet protein.

Asbestosis and the serratus anterior muscle

Twenty-seven patients with a history of asbestos exposure were reviewed at the UCLA Medical Center in December 1981. All patients were referred by the United States Department of Labor. The patients were told they had asbestosis on the basis of their history of exposure and chest radiographs taken at a local asbestos screening program and initially interpreted by a "B" reader. None of the 27 patients reviewed were found to have evidence of asbestosis either clinically or radiographically. The false-positive radiographic interpretations were due to the extrathoracic musculature (serratus anterior) mimicking intrathoracic disease. Since the study described here was done, an additional 330 patients have had their radiographs reviewed.

Pap smear screening and invasive cervical cancer

Possible failures of Pap smear screening were assessed among 63 cases of invasive cervical cancer that occurred in a group practice population between 1965 and 1975. Review of medical records revealed 33 (53 percent) cases with no history of Pap smears within two years prior to diagnosis. Among the 30 patients with recent Pap screening, 11 (17 percent) had negative smears; these could only be explained as false negatives or unusually rapid progression of disease. The remaining 19 (30 percent) had abnormal smear results, a number of whom received suboptimal follow-up care. Similar experiences have been reported from several other health care settings. Implications for preventive practices are discussed.

The use of hybridoma antibodies to probe the antigenic determinants of thyroglobulin

Using monoclonal antibodies we have begun to define the epitopes of the murine thyroglobulin molecule that elicit autoimmune responses. Based on the principle of complementation, 18 monoclonal antibodies were classified into 8 groups, defined by their reactions with the same or neighboring determinants. Further distinctions between the monoclonals were drawn from comparisons of their cross-reactions with thyroglobulins of other species and their patterns in isoelectric focusing. One low molecular weight fragment of bovine thyroglobulin, which cross-reacts extensively with thyroglobulins of other species, has been isolated and partially characterized.

Distribution and elimination of melphalan in rats and monkeys and distribution in tumors of mice bearing L1210 or P388 leukemias sensitive and resistant to this agent

Following iv injection, melphalan was eliminated monophasically from rat serum (half-life = 0.87 hour) and monkey serum (half-life = 1.9 hours) and in rat bile (half-life = 2.4 hours) and monkey urine (half-life = 1.3 hours). In rat bile and monkey urine, 2% and 20% of the dose, respectively, was excreted in 12 hours as unchanged melphalan. At each time of tissue assay (0.5-4 hours after injection), rat spleen contained less melphalan than serum, liver, or kidneys. The kidneys and bile of monkeys contained more melphalan that serum, liver, or spleen. Only a small amount of radioactivity from labeled melphalan appeared in the feces of monkeys. Melphalan reached higher concentrations in implants of P388 and L1210 leukemia cells sensitive to melphalan than in cell lines resistant to this drug. Furthermore, the amounts of radioactivity bound to macromolecules of the sensitive tumors were higher.

The broken wire suture

The body is a hostile environment for wire sutures. Although the problems of electrochemical corrosion, direct chemical attack on the suture, and inflammation produced in reaction to the suture have been largley eliminated by the use of austenitic stainless steel wires, failure of the wires may still occur due to mechano-chemical cracking -- the combined effect of insignificant stresses, usually from cold working, and insignificant chemical potentials produced by body fluids. Although stainless steel wire remains a satisfactory material for sternotomy closure or for reattaching costal cartilages, the two spectacular complications of a broken wire point out the need for care in using wire sutures. Bending, twisting, kinking and knotting must be avoided as much as possible.

Pharmacokinetics of the absorption, distribution, and elimination of melphalan in the dog

[14C]melphalan ([14C]L-PAM) was rapidly absorbed from the gut of dogs after oral dosing and reached a maximum concentration in the serum by 30 minutes. The disappearance of L-PAM (intact drug) from the serum was biphasic after iv administration, with half-lives of 14 and 66 minutes for the alpha and beta phases, respectively. The urinary excretion accounted for 44% of the total radioactivity and 25% appeared in the feces. Approximately 8% of the dose was excreted unchanged in the urine. Biliary excretion was rapid, with 11% of the dose being accounted for in the bile after 30 minutes; approximately 80% of these drug equivalents (materials containing radioactivity) was parent compound. Since large amounts of L-PAM appeared in the bile, the agent may prove to be active against cancers of the gall bladder, bile ducts, and duodenum.

A method for the measurement of L-phenylalanine mustard in the mouse and dog by high-pressure liquid chromatography

The distribution of L-phenylalanine mustard (L-PAM) was studied in dogs and mice by high-pressure liquid chromatography. Separation of L-PAM from its products of hydrolysis was accomplished with a mu-Bondapak C18 column, a solvent system composed of 2-methoxyethanol/0.1% acetic acid, and solvent programming with a step gradient. Complete separation was effected in less than 15 min. The half-life for disappearance of L-PAM from mouse blood was 41 min, whereas that from dog blood was 29 min. The monohydroxy derivative of L-PAM, L-MOH, disappeared from dog serum with a half-life of 32 min. L-MOH was not detectable in mouse tissue other than blood at times greater than 15 min after injection. In the dog at 4 hr after injection, the tissue/serum concentration ratios were greater than 1 for liver, spleen, intestine, skeletal muscle, urinary bladder and gallbladder. The concentration of L-PAM in the bile was approximately 500 times higher than that in serum.

Multiple antigenic sites on an eicosapeptide. I. Precipitin studies in the goat

Purified peptide 105-124, an antigenic determinant from the carboxy terminus ribonuclease, was found to form an immune precipitate with antibody to that region prepared by affinity chromatography from goat hyperimmune antiserum to reduced carboxymethylated ribonuclease (CM-RNase). Cm-rnase also gave an immune precipitate with the antibody. Purified antibody to another region of similar size (40-61) did not form a precipitate with CM-RNase but did co-precipitate in the presence of antibody to peptide 105-124 and CM-RNase. The precipitin reaction between antibody to peptide 105-124 and CM-RNase was inhibited by two synthetic derivatives, peptides 118-124 and ala114-RNase 114-124. Stoichiometry of the precipitin reactions of antibody to 105-124 with CM-RNase or peptide 105-124 suggested an antigen valency of three or more. Consistent with this both peptides 105-124 and ala114-RNase 114-124 elicited immediate cutaneous reactions but 118-124 did not. These findings suggest that the eicosapeptide 105-124 is multivalent since at least three antibodies can react simultaneously with it.