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W Ensminger

Publications and source records attributed to W Ensminger.

6 recordsLinked to original sources

Malignant hepatic tumors: P-31 MR spectroscopy with one-dimensional chemical shift imaging.

To determine the clinical feasibility and applicability of phosphorus-31 magnetic resonance (MR) spectroscopy and to assess its potential for characterization of human hepatic tissue, one-dimensional chemical shift imaging (CSI) was performed in 37 patients with various malignant hepatic neoplasms (30 metastases from a variety of primary tumors and seven hepatocellular carcinomas) and seven healthy volunteers. Tumors were grouped according to the percentage of the analyzed section that was occupied by tumor: less than 50% (group A) or more than 50% (group B). In group B, all phosphomonoester/beta-adenosine triphosphate ratios were significantly higher than normal (P less than .001). Hepatocellular carcinomas and metastases from various primary neoplasms could not be differentiated on the basis of spectral characteristics and metabolite ratios. Limitations of one-dimensional surface coil CSI prevented separation of spectra of small tumors and tumors deep within the liver parenchyma from spectra of normal liver parenchyma.

Adenosine Triphosphate

Random sampling by glitter drop method.

In the course of a study on glioblastoma tissue and cultured cell lines, a glitter drop technique for random sampling was introduced (1). Here, we report the initial description of the details of this procedure and its application to cell counts from explant slides and to determining bromodeoxyuridine (BUdR) labeling indices (LI) in tissues. The method is without bias, easy to perform and takes only a short time. It compares well with three other generally used random sampling procedures.

Bromodeoxyuridine

Hepatic arterial chemotherapy for primary and metastatic liver cancers.

Hepatic arterial chemotherapy represents a means of selectively exposing hepatic tumor to cytotoxic agents. Although 5-fluoro-2'-deoxyuridine has been shown to generate a higher response rate in the treatment of colorectal liver metastases than that achieved by intravenous infusion, responses are largely incomplete and rarely of long duration. This review describes the rationale for the use of the thymidine analogs 5-bromo-2'-deoxyuridine and 5-iodo-2'-deoxyuridine in hepatic arterial infusions and indicates how combination therapy adding radiotherapy, specifically with hepatic arterially administered yttrium-90 microspheres, might generate a new, more efficient and effective therapeutic approach.

Bromodeoxyuridine

Floxuridine-associated sclerosing cholangitis. A dog model.

The authors developed a dog model for the biliary sclerosis that occurs as a severe complication of protracted hepatic arterial floxuridine (FUDR) infusions (using implanted drug delivery systems) in patients with hepatic cancers. Infusaid pumps attached to hepatic arterial catheters were used for protracted infusions in ten mixed breed hounds. To allow repeated cholangiograms, the animals' gallbladders were removed and catheters connected to subcutaneous infusion ports were positioned in the cystic ducts. Five treated dogs received FUDR 0.3 mg/kg/day through the pump for a total of 30 days. Five control dogs received only saline through the pump. Cholangiograms were obtained before and after treatment in all animals. In the control group, serum liver function test results and the cholangiographic appearance of the biliary tree remained within normal limits. By contrast, in the FUDR-treated group, serum glutamic-pyruvic transaminase and alkaline phosphatase progressively rose above normal, starting 2-3 weeks into FUDR infusion, followed by hyperbilirubinemia (7-28 mg/dl peak levels) beginning 4 to 6 weeks after initiation of the drug infusion. Cholangiograms revealed focal strictures involving the central bile ducts (five dogs) and diffuse attenuation of the intrahepatic ducts (four dogs). Thus, the liver function abnormalities and the cholangiographic findings in this dog model mimic the hepatobiliary toxicity in sensitive patients receiving similar treatment.

Animals

Comparative effects of citrovorum factor and carboxypeptidase G1 on cerebrospinal fluid-methotrexate pharmacokinetics.

A comparison between citrovorum factor (CF) and carboxypeptidase G1 (CPDG1) rescue with respect to cerebrospinal fluid (CSF)-methotrexate (MTX) disappearance was studied in a patient with recurrent medulloblastoma who had a ventriculoperitoneal shunt. CPDG1 rescue resulted in a prolonged CSF-MTX half-life of 16.5-23 hours in comparison with CF rescue where the CSF-MTX half-life was 6.5-7.2 hours. There was a positive clinical response measured by loss of bone pain, increased physical activity, and almost complete clearing of CSF blast cells. CPDG1 rescue after high-dose MTX may provide more intense and selective treatment for meningeal neoplasms.

Adolescent